There is still no consensus on which concentration of mesenchymal stem cells (MSCs) to use for promoting fracture healing in a rat model of long bone fracture. To assess the optimal concentration of MSCs for promoting fracture healing in a rat model. Wistar rats were divided into four groups according to MSC concentrations: Normal saline (C), 2.5 × 106 (L), 5.0 × 106 (M), and 10.0 × 106 (H) groups. The MSCs were injected directly into the fracture site. The rats were sacrificed at 2 and 6 자 post-fracture. New bone formation [bone volume (BV) and percentage BV (PBV)] was evaluated using micro-computed tomography (CT). Histological analysis was performed to evaluate fracture healing score. The protein expression of factors related to MSC migration [stromal cell-derived factor 1 (SDF-1), transforming growth factor-beta 1 (TGF-β1)] and angiogenesis [vascular endothelial growth factor (VEGF)] was evaluated using western blot analysis. The expression of cytokines associated with osteogenesis [bone morphogenetic protein-2 (BMP-2), TGF-β1 and VEGF] was evaluated using real-time polymerase chain reaction. Micro-CT showed that BV and PBV was significantly increased in groups M and H compared to that in group C at 6 wk post-fracture (P = 0.040, P = 0.009; P = 0.004, P = 0.001, respectively). Significantly more cartilaginous tissue and immature bone were formed in groups M and H than in group C at 2 and 6 wk post-fracture (P = 0.018, P = 0.010; P = 0.032, P = 0.050, respectively). At 2 wk post fracture, SDF-1, TGF-β1 and VEGF expression were significantly higher in groups M and H than in group L (P = 0.031, P = 0.014; P < 0.001, P < 0.001; P = 0.025, P < 0.001, respectively). BMP-2 and VEGF expression were significantly higher in groups M and H than in group C at 6 wk postfracture (P = 0.037, P = 0.038; P = 0.021, P = 0.010). Compared to group L, TGF-β1 expression was significantly higher in groups H (P = 0.016). There were no significant differences in expression levels of chemokines related to MSC migration, angiogenesis and cytokines associated with osteogenesis between M and H groups at 2 and 6 wk post-fracture. The administration of at least 5.0 × 106 MSCs was optimal to promote fracture healing in a rat model of long bone fractures.
To determine the major risk factors for unplanned reoperations (UROs) following corrective surgery for adult spinal deformity (ASD) and their interactions, using machine learning-based prediction algorithms and game theory. Patients who underwent surgery for ASD, with a minimum of two-year follow-up, were retrospectively reviewed. In total, 210 patients were included and randomly allocated into training (70% of the sample size) and test (the remaining 30%) sets to develop the machine learning algorithm. Risk factors were included in the analysis, along with clinical characteristics and parameters acquired through diagnostic radiology.Aims
Methods
Distal interphalangeal joint (DIPJ) fusion using a k-wire has been the gold standard treatment for DIPJ arthritis. Recent studies have shown similar patient outcomes with the headless compression screws (HCS), however there has been no cost analysis to compare the two. Therefore, this study aims to 1) review the cost of DIPJ fusion between k-wire and HCS 2) compare functional outcome and patient satisfaction between the two groups. A retrospective review was performed over a nine-year period from 2012-2021 in Counties Manukau. Cost analysis was performed between patients who underwent DIPJ fusion with either HCS or k-wire. Costs included were surgical cost, repeat operations and follow-up clinic costs. The difference in pre-operative and post-operative functional and pain scores were also compared using the patient rate wrist/hand evaluation (PRWHE). Of the 85 eligible patients, 49 underwent fusion with k-wires and 36 had HCS. The overall cost was significantly lower in the HCS group which was 6554 New Zealand Dollars (NZD), whereas this was 10408 NZD in the k-wire group (p<0.0001). The adjusted relative risk of 1.3 indicate that the cost of k-wires is 1.3 times more than HCS (P=0.0053). The patients’ post-operative PRWHE pain (−22 vs −18, p<0.0001) and functional scores (−38 vs −36, p<0.0001) improved significantly in HCS group compared to the k-wire group. Literatures have shown similar DIPJ fusion outcomes between k-wire and HCS. K-wires often need to be removed post-operatively due to the metalware irritation. This leads to more surgical procedures and clinic follow-ups, which overall increases the cost of DIPJ fusion with k-wires. DIPJ fusion with HCS is a more cost-effective with a lower surgical and follow-up costs compared to the k-wiring technique. Patients with HCS also tend to have a significant improvement in post-operative pain and functional scores.
Treatment of prosthetic joint infection (PJI) following total knee arthroplasty (TKA) may guided by PJI classification, taking into account infection duration and potential for biofilm formation. Debridement, antibiotics and implant retention (DAIR) is recommended for ‘post-operative’ and ‘acute’ haematogenous PJI. However, the time cut-off for ‘post-operative’ PJI varies across classification systems. Furthermore, poor DAIR success rates have been reported in acute haematogenous PJIs. This study aimed to determine the success of DAIR in a large cohort of PJIs, and assess the utility of current classification systems for predicting DAIR outcomes. In this multicentre retrospective, cohort study, we identified 230 patients undergoing DAIR for first episode PJI following primary TKA. Patient demographics, disease and surgical factors were identified, and PJI subtype, post-operative antibiotic regime and treatment outcomes were recorded. Statistical analysis was performed to identify factors associated with failed DAIR, and success rates were analysed by multiple classification systems using receiver operating characteristic (ROC) curves.Introduction
Method
The aim of this study was to assess the clinical and radiological result of the usage of chip bone graft in non-contained type bone defect in primary or revision total knee arthroplasty patients. We investigated 32 patients who had underwent primary or revision total knee arthroplasty from March, 2014 to February, 2017 in our hospital, who had non-contained type of defect. The mean age was 73.1 years. 5 of them were males, while 27 of them were females. 7 of them were primary total knee arthroplasty patients, while 25 of them were revision patients. 8 of them had chip bone graft used both in the femur and tibia. 9 of them had chip bone graft used only in the tibia. The other 15 had chip bone graft used only in the femur. Wire-mesh was used in the 9 patients who had chip bone graft used only in the medial side of the tibia. We used KOOS (Knee injury and osteoarthritis outcome score), HSS (Hospital for Special Surgery knee service rating system) and WOMAC scores to assess the clinical result, before the surgery and at the last follow-up. In addition, we had follow-up x-rays and 3D CT done for the patients to check the mean bone union period. In addition, overall radiologic imaging studies were used for complications such as loosening, osteolysis and lesions with radiolucency.Purpose
Subjects and Methods
The aim of this study was to compare the clinical outcomes of the revision TKA in which trabecular metal cones and femoral head allografts were used for large bone defect. Total 53 patients who have undergone revision TKA from July 2013 to March 2017 were enrolled in this study. Among them, 24 patients used trabecular metal cones, and 29 patients used femoral head allografts for large bone defect. There were 3 males and 21 females in the metal cone group, while there were 4 males and 25 females in the allograft group. The mean age was 70.2 years (range, 51–80) in the femoral head allograft group, while it was 79.1 years (range, 73–85) in the metal cone group. Bone defect is classified according to the AORI classification and clinical outcomes were evaluated with Visual Analogue Scale (VAS), Hospital Special Surgery-score (HSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS), and ROM. Operation time was also evaluated. We used radiographs to check complications such as migration or loosening. We took follow-up x-rays and 3D CT of the patients, to assess the mean bone union period. Shapiro-Wilk test was done to check normality and Student T-test and Mann Whitney U-test were done for comparison between two groups.Purpose
Method
Isolated liner and head exchange procedure has been an established treatment method for polyethylene wear and osteolysis when the acetabular component remains well-fixed. In this study, its mid-term results were evaluated retrospectively in 34 hips. Among the consecutive patients operated upon from September 1995, 2 patients (3 hips) were excluded because of inadequate follow-up and the results of remaining 34 hips of 34 patients were evaluated. They were 20 men and 14 women with a mean age of 49 years at the time of index surgery. Conventional polyethylene liner was used in 26 cases and highly cross-linked polyethylene liner was used in 8 cases. In 3 cases, liner was cemented in the metal shell because compatible liner could not be used. After a minimum follow-up of 5 years (range, 5∼20.2), re-revision surgery was necessary in 10 cases (29.4%); 8 for wear and osteolysis, 2 for acetabular loosening. In all re-revision cases, conventional polyethylene was used. There was no failure in the cases in which highly cross-linked polyethylene was used. There was no case complicated with dislocation. The results of this study suggest more promising results with the use of highly cross-linked polyethylene in isolated liner exchange.
Venous thromboembolism (VTE) is a common, costly, and morbid complication following TJA. Consequently, the current standard of care recommends that all TJA candidates receive some form of thromboprophylaxis postoperatively. Chemoprophylaxis, however, is not without its own risks and has been associated with greater risk of perioperative complications such as major bleeding, infection, stroke, and increased wound drainage. Mechanical compression devices serve as an alternative to chemoprophylaxis. Compression devices are thought to function by decreasing venous stasis and activating fibrinolysis. Intermittent pneumatic compression devices (IPCD) function by providing pressure at a constant cycle; whereas continuous enhanced circulation therapy (CECT) devices such as ActiveCare portable system (Medical Compression Systems, Or Akiva, Israel) function in a synchronized manner with the patient's own respiratory cycles. While both of these systems are widely utilized, there is scarce data comparing their effectiveness as thromboprophylatic agents following TJA. The purpose of this meta-analysis is to comparatively evaluate the efficacy of ActiveCare to IPCDs in the prevention of thromboembolic events following TJA. A literature search using PubMed, Cochrane, and EMBASE databases were used to identify all articles published between January 2000 and August 2016. Key words used to conduct the search were venous foot pump, intermittent pneumatic compression, total hip arthroplasty/replacement, total knee arthroplasty/replacement, deep vein thrombosis, thromboembolic disease and pulmonary emboli. Two independent investigators carried out the literature review using the PRISMA guidelines (Figure 1). Analysis of risk ratio was performed by evaluation of studies which compared IPCD with any control chemoprophylaxis regiment or ActiveCare with any control chemoprophlaxis regiment. Assessment of heterogeneity and analysis of data were operated by Review Manager 5.3.Background
Methods
Although total knee arthroplasty (TKA) in end-stage hemophilic arthropathy can reduce the severe joint pain and improve the functional disability, it is technically demanding. In addition, it has generally reported a high rate of complication including periprosthetic joint infection (PJI) and component loosening up to 20%. Although the Knee Society classification system of TKA complication was introduced, the complications of TKA in hemophilic arthropathy has not stratified using this classification system in previous articles to the best of our knowledge. The purpose of this study was to evaluate the mid-term outcomes and complications of TKA in hemophilic arthropathy. The study retrospectively reviewed 131 consecutive primary TKAs (102 patients) in single institute. The mean patient age was 41.0 years and mean follow-up time was 6.4 years. The clinical and radiographic results were evaluated. The complications were categorized according to the classification system of the Knee Society for TKA complications.Introduction
Methods
The aim of this study was to determine the optimal regimen for
the management of pain following total knee arthroplasty (TKA) by
comparing the outcomes and cost-effectiveness of different protocols
implemented at a large, urban, academic medical centre. Between September 2013 and September 2015, we used a series of
modifications to our standard regimen for the management of pain
after TKA. In May 2014, there was a department-wide transition from
protocols focused on femoral nerve blocks (FNB) to periarticular
injections of liposomal bupivacaine. In February 2015, patient-controlled analgesia
(PCA) was removed from the protocol while continuing liposomal bupivacaine
injections. Quality measures and hospital costs were compared between
the three protocols.Aims
Patients and Methods
We conducted a prospective study of a delta ceramic total hip
arthroplasty (THA) to determine the rate of ceramic fracture, to
characterise post-operative noise, and to evaluate the mid-term
results and survivorship. Between March 2009 and March 2011, 274 patients (310 hips) underwent
cementless THA using a delta ceramic femoral head and liner. At
each follow-up, clinical and radiological outcomes were recorded.
A Kaplan-Meier analysis was undertaken to estimate survival.Aims
Patients and Methods
The fourth generation ceramic, in which zirconia is incorporated into the alumina matrix, was developed to reduce the risk of ceramic fractures. The purpose of this study was to evaluate the survivorship, clinical and radiographic results, and bearing-related failures associated with total hip arthroplasty using zirconia-toughened alumina ceramic-on-ceramic bearings over a minimum follow-up of 5 years. We retrospectively analysed 135 patients (151 hips) who underwent cementless total hip arthroplasty using zirconia-toughened alumina ceramic-on-ceramic bearings. There were 58 men and 77 women with mean age of 55.9 years (range, 20 to 82 years) at index surgery. Acetabular and femoral components were cementless in all hips. A 36 mm head was used in 81 of 151 hips and a 32 mm head was used in 70 hips with smaller acetabular shells. The mean duration of follow-up was 6.1 years (range, 5 to 6.8 years).Purpose
Materials and methods
To evaluate the causes and modes of complications after unicompartmental knee arthroplasty (UKA), and to identify its prevention and treatment method by analyzing the complications after UKA. A total of 1,576 UKAs were performed between January 2002 and December 2014 at a single-institution. Postoperative complications occurred in 89 knees (83 patients, 5.6%), and 86 of them were found in females and 3 in males. Their mean age was 61 years (range, 46 to 81 years) at the time of initial UKA and 66 years (range, 46 to 82 years) at the time of revision surgery. We analyzed the complications after UKA retrospectively andinvestigated the proper methods of treatment (Table 1).Background
Materials and Methods
The use of tranexamic acid (TXA) in primary total hip arthroplasty (THA) is supported by many studies that confirm its efficacy for decreasing blood loss, but the comparison between topical intra-articular (IA) and intra-venous (IV) is unclear, especially combined with chemical prophylaxis. The purpose of this study is to verify non-inferior efficacy of topical IA TXA compared with IV TXA in primary THA. A single center, randomized, controlled clinical trial was performed to compare topical IA TXA (2 g of TXA in 100 cc of normal saline) with two IV doses of TXA (1 g dose before surgery and another 1 g dose 3 hours later) on blood loss. The primary outcome was total blood loss as calculated from the difference between the preoperative hemoglobin (Hb) and the lowest postoperative Hb. The secondary outcome included drained blood loss, transfusion volume, and thromboembolic events. The sample size of 112 patients was calculated to give a statistical power of 99% for demonstrating inferiority. Fifty-six patients each was assigned to receive topical IA TXA (IA group) and IV TXA (IV group). There were no significant differences in demographics and preoperative laboratory values between the two groups. Non-inferiority was estimated by comparing the confidence interval with a delta of 10%. All subjects took oral direct factor Xa inhibitor to prevent venous thromboembolism included during 2 weeks after surgery.Introduction
Methods & Methods
Buechel and Pappas invented a modified version of LCS RP system (Co-Cr) with light material (Titanium), axial rotation limiting bar and improved conformity. The purpose of this prospective randomized study was to compare the minimum 3-year clinical outcomes including lightness, preference, and instability between the Co-Cr implant system and the Titanium implant system in bilateral total knee arthroplasty. We prospectively enrolled 108 patients and 20 patients were lost to follow-up. Therefore, 88 patients (176 knees; mean age, 69.9±6.0years) were included in the study. The range of motion and clinical scores such as Knee Society score (KSS), Hospital for Special Surgery score (HSS) and Western Ontario and McMaster University (WOMAC) scores were measured preoperatively and postoperatively. At each follow-up, patients also complete a Likert scale questionnaire regarding subjective pain, lightness, left-right side preference (naturalness and satisfaction) and subjective instability. There were no significant differences in all preoperative variables between two groups (p>.05). Mean follow-up period was 46.3±8.8 (36 to 72) months. The mean weight of Titanium implants was three times lighter than that of Co-Cr implants (133.9g versus 390.1g, p<.01). At the minimum of 3-year follow-up, there were no significant differences in pain, range of motion (ROM), clinical scores including KSS, HSS, and WOMAC between both groups. Also, the study showed no significant differences with subjective pain, lightness, preference (convenience, naturalness, and satisfaction), and subjective instability between the Co-Cr protheses and the Titanium protheses (p>.05). No differences in clinical outcomes as well as subjective side-to-side differences between the Co-Cr prostheses and the Titanium prostheses were observed in the minimum 3-year follow-up. This implies that patients do not feel differently with two different weighted implants in mid-term follow-up.
In this study, we investigated the long-term clinical results and survivorship of minimally invasive unicompartmental knee arthroplasty (UKA) by collecting cases that have been implanted for >10 years ago. Medial UKA on 180 cases in 142 patients was performed over a period of 1 year after the first introduction of minimally invasive UKA from January 2002 to December 2002. Among these, 166 cases in 128 patients who underwent Oxford phase 3 medial UKA using the minimally invasive surgery, with the exclusion of 14 cases including 10 cases of follow-up loss and 4 cases of death, were selected as the subject. The mean age of the patients at the time of surgery was 61 years, and the duration of the follow-up was minimum 10 years. All the preoperative diagnosis was osteoarthritis of the knee joint. Clinical and radiographic assessments were measured by the Knee Society clinical rating system, and the survival analysis was confirmed by the Kaplan–Meier method with 95% confidence interval (CI).Background
Methods
To identify the modes of failure after total knee arthroplasty (TKA) in patients ≤ 55 years of age and to compare with those ≥ 56 years of age in patients who underwent revision TKA. We retrospectively reviewed 256 revision TKAs among patients who underwent TKA for knee osteoarthritis between January 1992 and December 2012. The causes of TKA failure were analyzed and compared between those ≤ 55 years of age and those ≥ 56 years of age. The age at the time of primary surgery was ≤ 55 years in 30 patients (31 knees) and ≥ 56 years in 210 patients (225 knees).Purpose
Materials and Methods
The purpose of this study is to analyse regional differences in the microstructural and mechanical properties of the distal femur depending on osteoarthritic changes using micro-images based on finite element analysis. Distal femur specimens were obtained from ten donors composed of 10 women with OA (mean age of 65 years, ranging from 53 to 79). As controls, the normal distal femur was sampled from age and gender matched donors consisting of 10 women(mean age of 67 years, ranging from 58 to 81). The areas of interest were six regions of the condyles of the femur(Lateral-Anterior, Middle, Posterior; Medial=Anterior, Middle, Posterior). A total of 20 specimens were scanned using the micro-CT system. Micro-CT images were converted to micro-finite element model using the mesh technique, and micro-finite element analysis was then performed for assessment of the mechanical properties.Purpose
Materials and Methods
Total hip arthroplasty (THA) is frequently performed as a salvage procedure for the acetabular fracture when posttraumatic osteoarthritis, posttraumatic avascular necrosis, or fixation failure with subluxation develop. Special considerations for this situation include previous surgical exposure with dense scar tissue, the type and location of implants, the location and amount of heterotopic ossification, indolent infection, previous sciatic nerve palsy, and the pathoanatomy of existing acetabular defect. These factors can influence the choice of surgical exposure and the reconstructive method. The outcomes of THA after acetabular fracture are generally less favorable than those of the nontraumatic degenerative arthritis. Reason for this high failure is the low mean age and the high activity level of the patient. Other important reasons for failure include the problem of acetabular bone deficiency and compromised bone quality. We evaluated the results of cementless THA in patient who had previous acetabular fracture. We also compared this result with those of patients with posttraumatic avascular necrosis of the femoral head. Forty-five consecutive cementless THAs were performed for the treatment of post-traumatic osteoarthritis after acetabular fracture between December 1993 and December 2008. Of these patients, 15 patients were died or lost to follow-up monitoring before the end of the minimum one year follow-up period. This left 30 patients (30 hips) as the subjects of our retrospective review. We evaluated the clinical and radiographic results of these patients and compared with the results of THA in patients with post-traumatic AVN of the femoral head which had without acetabular damage. Two hips required revision of the cup secondary to early migration of the acetabular cup (1 hip) and postoperative deep infection (1 hip). There was no significant difference in clinical and radiographic results between two groups except implanted acetabular component size and required bone graft (p<0.05). The Kaplan-Meier ten-year survival rate, with revision as the end-point, was 90% and 96.7% with loosening of acetabular component as the end-point. Our series suggested that compared with cemented components, uncemented sockets may improve the results of arthroplasty after previous acetabular fracture. In conclusion, cementless THA following acetabular fracture presents unique challenge to the surgeon, careful preoperative assessment and secure component fixation with proper bone grafting is essential to minimize problems.
ACL reconstruction using a quadriceps tendon autograft was quantitatively evaluated using a robotic testing system. Biomechanical results on joint stability and graft function support its use as an alternative to the hamstrings. Recently, a number of surgeons have chosen the quadriceps tendon (QT) autograft as an alternative autograft over the hamstrings tendon for ACL reconstruction because its bone-to-bone healing on one side, large size, and preservation of lateral and rotatory knee function could lead to fewer post-operative complications. However, there have been little or no biomechanical studies that quantitatively evaluate knee function after reconstruction using a QT autograft. Therefore, the objective of this study was to assess the function of a reconstructed knee with a QT autograft and compare the results with a quadrupled semitendinosus and gracilis (QSTG) tendon autograft on the same knee.Summary Statement
Introduction
To investigate treatment patterns and efficacy of postoperative strong opioids in patients who underwent total knee arthroplasty (TKA) in Korea A prospective, non-interventional study of 301 patients who underwent TKA and received strong opioids following patient controlled analgesia (PCA) was conducted by reviewing patient charts and diaries from 19 teaching hospitals. Clinical characteristics, strong opioid treatment patterns, efficacy of strong opioid on a scale of 0–10, and opioid-related adverse events (AEs) were investigated during hospitalization and at first outpatient visit. Safety analysis was conducted on 301 patients, and efficacy analysis was conducted on full analysis set (FAS) which consisted of all the patients who had at least 1 efficacy result among 301 patients.Purpose:
Methods:
The purpose of this study is to compare the results of total knee arthroplasty between non-adrenal insufficiency group and adrenal insufficiency group undergoing steroid replacement during surgery 89 patients (89 knees) treated with TKA were enrolled in this study. We classified the patients with adrenal insufficient(AI) group and nonadrenal insufficient (NAI) group by preoperative adrenal function. Levels of serum cortisol, adrenocorticotropic hormone(ACTH), and ACTH stimulation test were checked preoperatively. Hydrocortisone 50∼75 mg was injected to adrenal insufficient group at 7:00 AM and 4:00 PM on operative day and the following day. We evaluated the range of motion, the knee society knee score and function score at preoperatively and 2 years follow up, and compared the results between NAI group and AI group.Purpose
Patients and Methods
To identify the causes of failure after unicompartmental knee arthroplasty (UKA), and to evaluate considerations for surgical procedures and the results of revision total knee arthroplasty (TKA) performed after failure of UKA. Eight hundreds and fifty-two cases of UKA were performed from January 2002 to June 2011. Forty-seven cases of failures after UKA were analyzed for the cause of the failures, and thirty-five cases of revision TKA after failure were analyzed for the operative findings and surgical technique. The clinical results were measured for thirty cases which were followed-up on at least two years after TKA. The mean duration of follow-up was four years and one month after revision TKA and the mean patient age at the time of surgery was sixty-five years.Purpose
Materials and Methods
Correct alignment of tibial and femoral components is one of the most important factors that determine favorable long-term results of total knee arthroplasty (TKA). Computer-assisted TKA allows for more accurate component positioning and continuous intraoperative monitoring of the alignment. However, the pinholes created by the temporally anchored pins used as reference points may cause problems. Here we report a case of tibial stress fracture that occurred after a TKA was performed with the use of a computer navigation system. The patient, a 76-year-old woman (height 157 cm, weight 73 kg and BMI 29.5 kg/m2) with bilateral knee osteoarthritis. The right knee was replaced first and recovered without complications. The left knee was replaced 2 weeks later. The patient underwent computer-assisted (Stryker Co., Allendale, NJ, USA), cemented, posterior cruciate ligament sacrificing replacement of the left knee (with a Zimmer Gender Solutions Knee). A midline skin incision was made and a 5.0 mm bicortical self-tapping anchoring pin was inserted 10 cm below the tibiofemoral joint line. The other anchoring pin was inserted into the femur at the same distance from the joint to the line. These pins were inserted bicortically, anterior to posterior. Femur and tibia resections were performed according to the light-emitting diode tracker on the navigation system and cutting jig. Femoral and tibial implants were fixed with cement. The anchoring screws were then removed after the fixation of all implants. For two weeks, the patient tolerated significant walking but experienced only vague pain and swelling at the site of the left proximal tibial area. Local heat or redness was not observed and inflammatory serological markers (erythrocyte sedimentation rate, c-reactive protein level and white blood cell count) were within normal limits. One week later the patient complained of more aggravated and persistent pain. The patient immediately had a radiography check-up which showed a long linear radiolucent line and cortical defect through the pinholes (Fig. 1A–D). Through close scrutiny of the radiographs taken immediately after and two weeks after the operation, it was realized that she had a tibial stress fracture resulting from a misplaced fixation pin (Fig. 2A, B). As a result, the patient wore a long leg splint and was instructed to avoid weight bearing for two weeks. She was then allowed to gradually put more weight after wearing along leg cast for four weeks. Clinically, a satisfactory outcome was reported by the patient with good recovery of her daily activities; crutches were no longer needed to walk after three months. Physical examination showed no tenderness and final ROM was 0–120 degrees. Radiography showed that the stress fracture was completely healed (Fig. 3A, B). Conclusively, we suggest that unicortical anchoring pins with a small diameter should be considered for use in the metaphyseal area and avoidance of transcortical drilling is recommended. Care should be taken to avoid stress fracture during rehabilitation in case of the development of pain after a pain-free period following computer assisted TKA.Case report
The purpose of this study is to analysis and compare the micro-structural and mechanical properties of subchondral trabecular bone of non-osteoarthritic and osteoarthritic distal femur using a micro-images based on finite element analysis. Fifteen distal femur were harvested from the eight cadevers(5 males, 3 females; non-OA, 10, OA, 5). The subchondral trabeculae were obtained from the middle of artticular surface of distal femurs(Fig. 1). Cylinderical saw with 10 mm diameter was used to acquire trabecular bone core. Total 15 specimens were scanned using micro-CT (SkyScan-1172, SKYSCAN, Belgium) at 24.9ãŽ> of spatial resolution under 70ãŽ,'s voltage and current of 141ãŽ,. 2-D images with were established by an imaging software (TomoNT, SKYSCAN, Belgium) as shown in Fig. 2. Histomorphologic index, trabeculae thickness (Tb.Th), trabecular separation (Tb.Sp), bone volume (BV), bone volume fraction (BV/TV), structure model index(SMI) were determined by the ANT software (Table 1). Based on 2-D images, a finite element model was reconstructed (Fig. 3). Finite element analysis was done using BIONIX (CANTIBIO, Suwon, Korea). Yield stress (MPa), Stiffness was calculated with ANSYS 10.0(ANSYS, Inc) (Fig. 4).Purpose
Materials and Methods
We wanted to evaluate the clinical and radiological results of acetabular revision using the acetabular reinforcement ring and allograft impaction in patients with severe acetabular bony defect. 41 hips revision arthroplasty using reinforcement ring were performed between April 1997 and October 2005 and were followed up for more than two years. The cause of primary arthroplasty was AVN in 18 cases, secondary osteoarthritis (OA) in 17 cases, fracture in cases and primary OA in 1 case. The cause of revision arthroplasty was acetabular cup loosening in 20 cases, massive osteolysis in 14 cases, infection in 4 cases, liner dissociation in 2 cases, and recurrent dislocation in 1 case. The average period between primary and revision arthroplasty was 11.4 years (range 0.6 to 29.1 years). Acetabular defects were classified based on the AAOS classification and Paprosky classification system. All were treated with autografts or allografts. Muller ring was used in 18 cases, Burch-Schneider ring was used in 14 cases, and Ganz ring in 9 cases. Clinical evaluations were performed according to the Harris hip score (HHS), and the radiographic results were evaluated by progression of acetabular component loosening, union of bone grafts, periacetabular osteolysis, and migration of the hip center. The mean preoperative Harris hip score of 64.9 was improved to 91.8 points at the latest follow-up. There were 39 cases of type 3 defect, 2 cases of type 4 defect according to the AAOS classification and 8 cases of type 2B defect, 3 cases of type 2C defect, 28 cases of type 3A defect, and 2 cases of type 3B defect according to Paprosky classification. Radiographically, the bone grafts were well united except one case. The mean preoperative hip center of rotation which was vertically 32.3mm, horizontally 33.2 mm migrated to vertically 26 mm, horizontally 33.2 mm postoperatively and it was statistically significant. The mean preoperative abductor lever arm of 41.7 mm changed to 45 mm postoperatively which was statistically insignificant. However the mean preoperatiave body lever arm of 89.4 mm changed to 96.9 mm postoperatively which was statistically significant. Postoperative complications were cup loosening in 1 case, dislocation in 2 cases, and recurrence of deep infection in 1 case. Clinically and radiographically, acetabular reconstruction using reinforcement ring showed very promising short term result. We conclude that reinforcement ring can provide stable support for grafted bone in severe bone defect. But meticulous surgical technique to get initial firm stability of ring and optimal indication in mandactory for the successful result.
Reconstructive acetabular osteotomy is a well established and effective procedure in the treatment of acetabular dysplasia. However, the dysplasia is frequently accompanied by intra-articular pathology such as labral tears. We intended to determine whether a concomitant hip arthroscopy with peri-acetabular rotational osteotomy could identify and treat intra-articular pathology associated with dysplasia and thereby produce a favourable outcome. We prospectively evaluated 43 consecutive hips treated by combined arthroscopy and acetabular osteotomy. Intra-operative arthroscopic examination revealed labral lesions in 38 hips. At a mean follow-up of 74 months (60 to 97) the mean Harris hip score improved from 72.4 to 94.0 (p < 0.001), as did all the radiological parameters (p < 0.001). Complications included penetration of the joint by the osteotome in one patient, a fracture of the posterior column in another and deep-vein thrombosis in one further patient. This combined surgical treatment gave good results in the medium term. We suggest that arthroscopy of the hip can be performed in conjunction with peri-acetabular osteotomy to provide good results in patients with symptomatic dysplasia of the hip, and the arthroscopic treatment of intra-articular pathology may alter the progression of osteoarthritis.
The exact alignment of the femoral component is crucial for the success of hip resurfacing arthroplasty. This prospective study was performed to find whether the imageless computer-assisted navigation surgery can improve the accuracy during hip resurfacing arthroplasty by comparing the alignment of the femoral component implanted with navigation system and conventional-mechanical guided system. Forty patients were randomly allocated into 2 groups for resurfacing hip arthroplasty using Birmingham hip resurfacing system. In the conventional group, femoral component positioning was assisted by mechanical alignment guides. In the navigation group, it was assisted by an imageless computer-assisted surgical system of Vectorvision® (BrainLAB, Germany). We measured the difference between the preoperative plan of femoral component’s position and postoperative results on radiographs in the 2 groups In the conventional group, a median difference of the stem alignment was 5.4° (range, 0.2°–10.9°) and a median difference of the stem anteversion was 2.6° (range, 0°–6.5°). In the navigated group, a median difference of the stem alignment was 2.3° (range, 0.2°–4.9°) and a median difference of the stem anteversion was 1° (range, 0°–3.6°). These differences between the 2 groups were statistically significant (P<
0.05). In resurfacing arthroplasty with a hip navigation, the procedure showed a good performance and reliability. It is achieved with greater precision with a navigation system than a mechanical alignment system.
Computer navigation for total knee arthroplasty (TKA) has been increasingly used because it improves the accuracy of implant placement. However, some clinical cases have reported complications caused from pin holes during the computer navigated surgery. The objective of this study is to analyse the femoral fracture risk cause by the pin hole in the computer navigated TKA by using finite element analysis. Three dimensional finite element model of the human femur was developed from CT images. A parametric investigation was conducted to analyse the femoral fracture risk for the following parameters: hole sizes (3, 4, and 5 mm) and hole position (70, 100, and 130 mm above the distal end). Four different penetrations (unicortical, bicortical, half-bicortical, and transcortical) methods in tubular bone were considered in each model, where the half-bicortical penetration was defined that the pin hole was located between the holes of bicortical and transcortical penetrations. The finite element model was rigidly fixed to a distance of 25 mm above the distal end. The vertical load of 1500 N and the torsional load of 12 Nm were applied to the femoral head. The maximum von-Mises stress, which was chosen as the fracture risk factor, was then investigated around pin hole. The maximum von-Mises stress around the pin hole was the highest in the transcortical penetration for different hole sizes: 7.8~8.5, 15.7~16.2, 15.5~16.8, and 25.5~45.3 MPa under the vertical load, and 9.6~10.5, 9.7~11.0, 8.8~10.2, and 14.2~33.8 MPa under the torsional load in unicortical, bicortical, half-bicortical, and transcortical penetrations, respectively. For the different hole position, the maximum von-Mises stress around the pin hole was: 6.0~7.8, 15.7~24.7, 16.3~19.6, and 12.2~22.4 MPa under the vertical load, and 9.6~10.7, 9.7~11.5, 8.7~9.8, and 12.2~16.6 MPa under the torsional load in unicortical, bicortical, half-bicortical, and transcortical penetrations, respectively. For the pin hole size, the maximum stress increased only in the transcortical penetration regardless of the loads as the pin hole size increased. However, there was little meaningful difference between the hole positions for each penetration method. The results of this study suggested that it would be beneficial to avoid using the transcortical penetration and large size of pin with respect to reduction of femoral fracture risk since the high stress may cause the femoral fracture.
Even though spinal fusion has been used as one of the common surgical techniques for degenerative lumbar pathologies, high stiffness in the fusion segment could generate clinical complications in the adjacent spinal segment. To avoid these limitations of fusion, the artificial discs have recently used to preserve the motion of the treated segment in lumbar spine surgery. However, there have been lacks of biomechanical information of the artificial discs to explain current clinical controversies such as long-term results of implant wear and excessive facet contact forces. In this study, we investigated the biomechanical performance for three artificial discs in the lumbar spinal segments by finite element analysis. A three-dimensional finite element model of five spinal motion segments, from L1 to S, in intact lumbar spine was reconstructed from CT images. Finite element models of three artificial discs, semi-constrained and metal on polyethylene core type (ProDisc® II, Spine Solutions Inc., USA; Type I), semi-constrained and metal on metal type (MaverickTM, Medtronic Sofamor Danek Inc., USA; Type II), and un-constrained and metal on polyethylene core type (SB ChariteTM III, Dupuy Spine Inc., Switzerland; Type III) were developed. Each artificial disc was inserted at L4–L5 segment, respectively. Upper and lower plates of artificial discs were attached on the L4 and L5 vertebrae. Some parts of ligaments and intervertebral disc in L4–L5 motion segment were removed to insert artificial discs. Nonlinear contact conditions were applied on facet joints in lumbar spine model and artificial discs. Bottom of sacrum was fixed on the ground and 5Nm of flexion and extension moments were applied on the superior plate of L1 with 400N of compressive load along follower load direction. In extension, all three artificial disc models showed higher rotation ratio at the surgical levels, but lower rotations at the adjacent levels than those in the intact model. There was no big difference of the intersegmental rotations among the artificial disc models. For the comparison of the peak von-Mises stresses on the polyethylene core in flexion, 52.3 MPa in type I implant was higher than 20.1 MPa in Type III implant while the peak von-Mises stresses were similar, 25.3 MPa and 26.5 MPa in Type I and III, respectively in extension. The facet contact forces at the surgical level for the artificial disc models showed 140 to 160 N in extension whereas the facet contact force in the intact model was 60 N. From the results of this study, we could investigate the biomechanical characteristics of three different artificial disc models. The relative rotation at the surgical level would be increases at the early outcome after total disk replacement. The semi-constrained type artificial disc could generate higher wear risk of the implant than unconstrained type. Also all types of artificial disc model have higher risk of facet joint arthrosis, and especially in the semi-constrained and metal on metal type. The results of the present study suggested that more careful care must be taken to choose surgical technique of total disc replacement surgery.
The ultimate goal for treatment of osteonecrosis of femoral head (ONFH) is preserving the femoral head. We have tried to manage the patient who received failed joint preserving procedures with resurfacing arthroplasty if they fit the indicati385on. In this brief review, we wanted to clarify the role and technical concern of resurfacing arthroplasty as a salvage procedure after failed joint preserving operations for ONFH. Among 556 hips underwent resurfacing arthroplasty from September 1998 to October 2007, sixteen resurfacing arthroplasties (13 patients) were performed after failed joint preserving procedures for ONFH. Mean age at the operation was 39 years old. Seven vascularized fibular grafts, 3 multiple drillings, 3 core decompressions and 3 combined procedures were performed as initial operations. Mean duration from the index operation and resurfacing was 95 months. Mean follow up was 14 months. The patients were clinically evaluated with the Harris hip score, hip or thigh pain, and range of motion. As a radiological evaluation, we measured positions of the acetabular cup and femoral stem, radiographic changes at the neck and complications. The Harris hip score increased from 69.2 preoperatively to 89.5 at the final visit. Hip range of motions other than sagittal directions significantly improved after the operation. No patient complained of limb length discrepancy. One patient complained of unexplained hip pain, and another patient had trochanteric pain. Other than those two cases, all patients regained their pre-morbid activity level uneventfully. Radiologically, eleven femoral stems in anteroposteior and lateral radiographs were exactly aligned along the previous operative tracts. However, there were no clinical complications related to the position of femoral component. The only case that the acetabular cup was implanted in high inclination (60 degrees) experienced sustained unexplained hip pain. There was no another complications. Our experience suggests that even for the case of failed hip preserving procedures in ONFH, resurfacing arthroplasty can play a successful role as a salvage operation. Furthermore, this can be an excellent alternative between joint preserving procedures and conventional THA.
Spinal fusion has been used as the gold standard to treat some spinal disorders such as degenerative disc or disc herniation of the cervical spine. However, some clinical complications have been reported caused by high stiffness of spinal fusion. Recently, total disc arthroplasty using motion preservation devices such as artificial discs (ADs) have been proposed as an alternative treatment technique. In current study, we analysed biomechanical influences including inter-segmental motion, facet joint forces, and ligament stresses of two different clinical available ADs and compared with those of intact cervical spine in various loading conditions using finite element analysis. A three dimensional finite element model was developed for C2-C7 spinal motion segment based on CT images and previous anatomical literatures. The finite element models for two different types of ADs, semi-constraint (Prodisc-C®, Synthes, U.S.A) and un-constraint (Mobi-C®, LDR Spine, U.S.A), were developed. Each AD was inserted at C6–C7 segments. Superior and inferior plates of ADs were fixed on inferior plane of C6 and superior plane of C7 vertebrae, respectively. Based on the conventional surgical techniques, anterior longitudinal ligaments and some parts of intervertebral disc in C6–C7 motion segment were removed to insert ADs. Inferior plane of C7 vertebra was constrained in all directions and 1Nm of flexion, extension, lateral bending and torsion were applied on superior plane of C2 vertebra with 50N of compressive load along follower load direction. Rotation angle in flexion of C5–C6 segment in cases of semi-constraint and un-constraint AD was 3.3° and 3.7°, respectively. Both values were greater than that in case of the intact cervical spine by 18% and 32%, respectively. Rotation angle in extension, lateral bending and torsion were greater than intact model by 45%, 26% and 43% for the case of semi-constraint AD and 55%, 35%, 100% for the case of un-constraint one, respectively. In extension, facet joint forces were about two times higher than intact model in cases of semi-constraint and un-constraint AD. Also in flexion, on average, ligament stresses in cases of semi-constraint and un-constraint AD were higher than intact model by 66% and 116%, respectively. The results of this study showed that ADs were useful to generate inter-segmental motion at surgical level. And the un-constraint type of AD had higher mobility than semi-constraint one. However, high mobility of ADs would lead not only higher facet joint forces but also ligament stresses than intact cervical spine. Therefore, more careful care must be taken to choose surgical method of total disc arthroplasty.
The purpose of this study is to evaluate short to mid-term clinical and radiological results of metal on metal resurfacing arthroplasty in osteonecrosis of the femoral head (ONFH). 185 hips of 169 patients who underwent metal on metal resurfacing arthroplasty using Birmingham Hip Resurfacing system (Midland Medical Technololgies, Birmingham, UK) between December 1998 and May 2005 were available for this study and all cases were followed up over 3 years. All preoperative diagnoses were ONFH. The extents of necrotic area were analyzed by preoperative MRI scanning. Their mean age at the time of operation was 37.7(range, 16–67) years old and mean period of follow-up was 88(range, 36–113) months. For the clinical assessments, Harris hip scores, UCLA activity scores, pain and ROM were evaluated. Radiological changes such as radiolucencies around the stem, impingement sign, neck narrowing, osteolysis around head and neck junction, loosening of implants, heterotopic ossifications were evaluated in the serial antero-posterior, translateral radiographs of the hip joint. Preoperative necrotic area was average 42.7(range, 11.5–60) %. Clinically, the average Harris hip score was improved from 85.2 points to 97.1 points at final follow-up. Average UCLA activity scores at the last follow-up was 8.8 and almost of the patients showed high activity and returned to their original job. ROM were very satisfactory. Radiologically, the mean inclination of acetabular component was 48.0°. There were no radiolucent lines around the acetabular components, but 3 cases showed radiolucent lines around the stem of femoral components. Osteolytic lesions were noticed in 10 cases around head-neck junction. Nine hips had impingement signs around the head-neck junction. There was no case which showed evidence of stress shielding. Moderate neck narrowing were shown in 3 cases. There were 6 cases of heterotopic ossification. One hip had a revision surgery to a total hip arthroplasty using big metal ball because of loosening of acetabular component. There was no patient complained limb length discrepancy and no infection, dislocation, thigh pain. The midterm performance of metal on metal resurfacing arthroplasty in ONFH was very excellent in the aspects of pain relief, ROM of hip joints, rehabilitation and return to preoperative activity and minimization of common complications of conventional total hip arthroplasty. There was no mechanical failure related to the osteonecrosis and we can conclude that performing resurfacing arthorplasty in osteonecrosis less than 50% of extent can be justified. However, performing resurfacing arthroplasties in osteonecrosis of femoral heads needs meticulous surgical techniques and longer learning curve to prevent early failure. Even though our midterm follow-up study revealed excellent results, more long-term follow-up studies are mandatory to determine the survivorship and to verify the problems related to the increased serum metal ion and metal ion toxicity after resurfacing arthroplasty.
For radiographic assessment of THA, we must estimate a 3-D structure with 2-D images. Basically, it has been good. But even after a successful surgery, sometimes we encountered an undersized stem in radiograph. Interestingly, it was more frequent after we introduced surgical robot for primary THA. It sometimes brought a huge dilemma during planning and evaluating the surgery. We performed this study to elucidate the cause of this problem. We used image data of 30 consecutive THAs using ROBODOC (ISS, USA). The measurement was made with the built-in tool in the Orthodoc, which is for the CT-based preoperative planning, and digital imaging system (PiView, Infinitt, Korea). We measured femoral anteversion, tilting angle at corresponding level, the longest and shortest diameters of femoral canal and their ratio. Also we measured anteversion and alignment of the stem. The canal filling of the stem was measured in projected images with CT and postoperative radiographs. The mean femoral anteversion was 21.1±10.2°. The canal tiling angle was 39.3±7.9°(p<
0.01). The long and short diameters were 19.3±2.6° and 14.3±1.8°. The mean ratio between them was 0.8±0.08°. Canal filling at AP and lateral dimensions were 88.25±9.8% and 85.7±6.9%. In postoperative radiographs, they were 85.4±7.3%(p=0.05) and 88.0±6.1%(p=0.06). This result suggests that the femoral canal at this particular or more distal level is elliptically shaped constantly. It tilts (in axial plane) to the same direction but not to the same degrees with femoral anteversion. Because of this tilt, relatively well-fixed round femoral stem can be considered as undersized in plane radiograph. Therefore, rather than using two plain radiographs alone for postoperative evaluation, adding postoperative CT may provide appropriate accuracy for assessment. And surgeon should keep in mind this axial tilt during planning and evaluating a robotic THA, especially not to remove too much healthy cortical bones to obtain full distal filling.
In the knee joint surgery such as total knee arthroplasty (TKA), the implant should be inserted in proper position with correct bone alignment because the abnormal kinematics of implanted knees by implant mal-positioning or mal-alignment could cause failure of surgery. Therefore, quantitative information of a 3D kinematics of the knee joint is very helpful to evaluate the surgical treatment such as planning of size and alignment of the implant. In this study, a 2D/3D image matching method was developed to estimate the kinematics of the knee joint based on an automated pixel by pixel comparison of images. Two projection images were obtained from the 3D object in two perpendicular directions where the given dual X-ray images were taken. The 3D object was translated and rotated automatically and continuously until its projection images were matched with the X-ray images in a given tolerance range. The optimization algorithm was used to minimise the root mean square error between the gray scale values of each pixel in the projection image and the given X-ray image. For estimating the position and orientation of the knee joint, the 3D knee joint models were reconstructed from CT data. The 3D model was matched with the given dual X-ray images by using the developed 2D/3D image matching method. The tibial and femoral components were then combined into the whole knee joint model. By adding fiducial markers based on clinically conventional method, the posterior and mediolateral translation of femur with respect to tibia as well as the flexion angle were measured. In the experiment with the cubic phantom, the position errors were below 0.10 mm and the orientation errors were below 0.05 o when using dual X-ray images. For the given dual X-ray images, the relative in vivo kinematics of the femur was measured as the posterior translation was 3.0 mm and the mediolateral translation was 0.9 mm. In addition, the flexion angle of the knee joint from the sagittal view was 51o while the angle measured from the given X-ray image was 50 o. The previous 2D/3D image matching methods operated manually took long time and was dependent on the operator. Recently, automated image matching method has developed by applying optimization algorithms. In this study, the optimal position and orientation were obtained by the direct pixel by pixel comparison, which are easy to implement and modify the algorithm. The present automated method could accelerate the matching process and stabilise the repeatability. In addition, the image matching method with dual images was used to improve the out-of-plane accuracy since the image matching method with a single X-ray image has a limitation of methodology in detecting out-of-plane translation and rotation though the in-plane accuracy was acceptable. The present 2D/3D image matching method is a powerful tool for the accurate determinations of 3D position and orientation of the knee joint and could provide informative characterization of implant designs and surgical options of the knee surgery.
The purpose of this study is to analyze clinical and radiological results of total hip arthroplasty using the 3rd generation ceramic on ceramic articular surface. Between July 1999 and May 2005, 339 hips of 250 patients had primary cementless total hip arthroplasty with the 3rd generation ceramic on ceramic bearing implants. And 325 hips of 236 patients were followed up over 3 years. Male were 168 patients(237 hips) and female were 68 patients(88 hips). The mean age at the time of operation was 47.3(range, 25~76) years old and the mean follow up period was 62.4(range, 36~107.6) months. The preoperative diagnoses were osteonecrosis of the femoral head (ONFH) in 250 hips, secondary osteoarthritis in 55 hips(dysplasia in 35, infection sequalae in 12, LCP in 2, CDH in 2), hemophilic arthropathy in 9 hips, ankylosing spondylitis in 7 hips etc. We used Bicontact system(Aesculap, Germany) in 65 hips, Secur-FitTM(Stryker Howmedica Osteonics, USA) in 206 hips, Trilogy ABTM (Zimmer, USA) in 54 hips. Clinically, Harris Hip Score, thigh pain, squeaking and other complications were evaluated. Radiologically, the serial radiographs were analyzed. Clinically, the Harris hip score was improved from preoperative 66.0(19~91) to 96.2(58~100) at the last follow-up. Radiologically, there was no loosening of implants and visible wear and osteolysis. Heterotopic ossifications were noted in 5 cases. In complications, there was dislocation in one case, periprosthetic fracture in 2 cases and thigh pain in 9 cases. Intermittent squeaking sound has occurred in 8 cases(2.5%). Among these, one case of loud squeaking which happened after fall down had revision surgery. There was no infection and fracture of ceramic implant. Our midterm results of THA with the 3rd generation ceramic bearing system were very satisfactory and demonstrated that the 3rd generation ceramic bearings remain as an excellent bearing choice because of their superior wear characteristics. However, the results of this study suggests that the squeaking would be one of strong potential risk factors for failure of ceramic on ceramic total hip arthroplasty and we must be very cautious to prevent squeaking.
We report the results of Oxford unicompartmental knee arthroplasty after short term follow up. Twenty nine knees from 26 patients who had undergone Oxford unicompartmental knee arthroplasty from March 2002 to February 2006 were reviewed. There were 1 male(1 knee) and 25 females(28 knees) and average age was 65.9 years. The preoperative diagnosis was 22 cases of medial osteoarthritis and 7 cases of osteonecrosis of medial femoral condyle. The postoperative knee society pain and function score, Lysholm score and HSS(Hospital for Special Surgery) score were improved compared with preoperative scores. The AP tibiofemoral angle was improved from varus 2.8° preoperatively to valgus 6.6°. Three cases of medial tibial condyle fracture were occurred and 1 case of overhang of tibial component was observed. Three cases were revised due to component loosening. Even though high incidence of complication and loosening were observed, the clinical results of Oxford unicompartmental knee arthroplasty were improved in short term follow up. We thought that thorough preparations should be done prior to surgery and there was room for the improvement of femoral component design for the stability against rotational torque such as two pegs on the femoral component.
The aim of this study is to analyse the mid to long term results of cementless total hip arthroplasty (THA) performed in hemophilic coxarthrosis. Twenty-seven consecutive cementless THAs (23 patients) were performed at our institute for hemophilic coxarthrosis between June 1995 and June 2003. All these patients were followed up regularly for minimum 5 years and were included in this study. The average age at the time of surgery was 36 years (± 8.1) (range, 24–52 years). All the patients had hemophilia A. Twelve patients (52%) had more than 1 joint affected by hemophilic arthropathy. The mean follow-up period was 92 months (± 31.4) (range, 60–156 months). For clinical assessment we evaluated Harris hip score, range of motion, amount of transfusion and factor replacement, perioperative bleeding and the problems associated with the use of coagulation factors. For radiographic assessment, we evaluated the stability and fixation of components, various bone responses around the implants and complications such as loosening and osteolysis. The average Harris hip score improved from 60.7 (± 19.3) (range, 30–89) before surgery to 95.9 (± 3) (range, 90–100) at the latest follow-up. The hip range of motion increased in all planes of motion after the operation. The mean factor VIII requirement per THA was 37 500 units (± 18 500) (range, 19 000–90 000 units). During surgery and post operative period mean 1.5 units (± 1.5) (range, 0–5 units) of packed cells and 0.5 units (± 1.4) (range, 0–5 units) of fresh frozen plasma was required. There was episode of re-bleeding in 4 cases. In one of them, severe osteolysis around pelvis and femoral stem was noted due to pseudotumor. Radiographically, except 1 loosened cup, the fixation was stable in all cases at the latest follow-up. Heterotopic ossification was noted in 2 hips. Osteolysis was noted in 4 femurs and 5 acetabulae. In 1 case of severe osteolysis around the stem, morsellised bone graft was performed at 144 months after the index operation. One case of pseudotumor was waiting for surgery. One loosened cup was revised to a cemented cup. Unlike worrisome results of cemented THA, meticulously performed cementless THA for moderate or severe hemophilic arthropathy is safe and greatly effective in reducing pain, increasing the range of motion and improving the walking ability. However, special attention must be paid to the possible complications associated with re-bleeding such as pseudotumor around the hip. To obtain the best results multidisciplinary team comprising of pediatrician, hematologist, rehabilitation therapist and orthopaedic surgeon should be needed.
Osteoprotegerin (OPG) has been reported to be a novel protein that can suppress osteoclast differentiation and activation. This study examined the therapeutic effects of OPG on established periprosthetic osteolysis in a rat model. A bone cement prosthesis was inserted into the rat femur and polyethylene particles were continuously infused into the knee joint using an osmotic pump. After osteolysis was established in four weeks, rats were intravenously injected with vehicle (control group) or 1 mg/kg of OPG (OPG-1 group) or 10 mg/kg of OPG (OPG-10 group) every week until they were sacrificed at 8 weeks. Effects of direct injections of OPG into the knee joint were also investigated. Periprosthetic bone resorption was evaluated with bone mineral density and histomorphometric analysis of membranes composed of total area of interface membrane and inflammatory grading. Radiographs were evaluated for focal osteolysis with a blind manner. Periprosthetic bone resorption was significantly suppressed in OPG-10 group compared to the other groups (p <
0.05). Histomorphometric analyses showed less total area as well as less inflammatory grading of the interface membrane in OPG-10 group compared to other groups (p <
0.01). Radiographic osteolysis appeared to decrease in number in OPG-10 group. Direct injections of OPG into the knee joint appeared to be more effective compared to intravenous injections. The present study demonstrates that OPG has significantly restored the established periprosthetic osteolysis in our animal model. OPG may be a possible agent to retain the bone stock before revision surgery for failed prostheses. Conclusion: This study demonstrates that osteoprotegerin suppresses the progression of periprosthetic osteolysis and restores bone stock in a rat model.
The appearance of the ‘grand-piano sign’ on the anterior resected surface of the femur has been considered to be a marker for correct femoral rotational alignment during total knee replacement. Our study was undertaken to assess quantitatively the morphological patterns on the resected surface after anterior femoral resection with various angles of external rotation, using a computer-simulation technique. A total of 50 right distal femora with varus osteoarthritis in 50 Korean patients were scanned using computerised tomography. Computer image software was used to simulate the anterior femoral cut, which was applied at an external rotation of 0°, 3° and 6° relative to the posterior condylar axis, and parallel to the surgical and clinical epicondylar axes in each case. The morphological patterns on the resected surface were quantified and classified as the ‘grand-piano sign’, ‘the boot sign’ and the ‘butterfly sign’. The surgeon can use the analogy of these quantified sign patterns to ensure that a correct rotational alignment has been obtained intra-operatively.
We present the clinical and radiological results of percutaneous vertebroplasty in the treatment of 58 vertebral compression fractures in 51 patients at a minimum follow-up of two years. Group 1 consisted of 39 patients, in whom there was no associated intravertebral cleft, whilst group 2 comprised 12 patients with an intravertebral cleft. The Oswestry disability index (ODI) and visual analogue scale (VAS) scores were recorded prospectively. The radiological evidence of kyphotic deformity, vertebral height, leakage of cement and bone resorption around the cement were studied restrospectively, both before and after operation and at the final follow-up. The ODI and VAS scores in both groups decreased after treatment, but the mean score in group 2 was higher than that in group 1 (p = 0.02 (ODI), p = 0.02 (VAS)). There was a greater initial correction of the kyphosis in group 2 than in group 1, although the difference was not statistically significant. However, loss of correction was greater in group 2. Leakage of cement was seen in 24 (41.4%) of 58 vertebrae (group 1, 32.6% (15 of 46); group 2, 75% (9 of 12)), mainly of type B through the basal vertebral vein in group 1 and of type C through the cortical defect in group 2. Resorption of bone around the cement was seen in three vertebrae in group 2 and in one in group 1. There were seven adjacent vertebral fractures in group 1 and one in group 2. Percutaneous vertebroplasty is an effective treatment for osteoporotic compression fractures with or without an intravertebral cleft. Nonetheless, higher rates of complications related to the cement must be recognised in patients in the presence of an intravertebral cleft.
This study examined the inhibitory effects of anti-TNF-a antibody (anti-TNF) and a new bisphosphonate (TRK-530) on peri-implant oseteolysis in a rat model with continuous infusion of polyethylene particles. TRK-530 is a novel synthetic bisphophonate to have a direct effect on osteoclastic bone resorption as well as suppressive effects on bone resorbing cytokines from macrophages.
The purpose of current study was to describe the results of complex acetabular fractures treated with open reduction using transtrochanteric approach and arthrotomy of the hip joint. Fourteen consecutive patients with both column fractures of the acetabulum were treated with open reduction and internal fixation. All patients had various associated injuries. Among them, one patient had pelvic abscess associated with traumatic bowel perforation. The acetabulum was approached with Y-shaped triradiate incision, osteotomy of the greater trochanter, and arthrotomy of the hip joint. During the operation, the osteochondral fragments were removed and torn labrum was resected. In 6 patients the fracture was fixed with reconstruction plates and in 8 patients the fracture was fixed with plates and wires. All the patients were followed for an average of 4.6 years(range, 2–8 years). The clinical evaluation was done by the method of Merle d’Aubigne. All the fractures and all osteotomies united at the latest follow up. One patient had delayed hematogenous infection at 5.5 years after the operation. Although myositis ossificans developed in 3 patients it was neither progressive after 1 year nor associated with significant limitation of hip motion. Four patients had narrowing of the hip joint space. Three of them had osteophyte formation around the femoral head. No femoral head necrosis was observed. Eleven patients had excellent or good outcomes in clinical score. No patient underwent total hip arthroplasty. This extensile approach allowed a good exposure of the fracture site, more accurate reduction, and easier fixation of fracture fragments. It also allowed the removal of osteochondral fragments and the resection of torn labrum. However, 3 patients showed osteophyte formation around the femoral head. We are concerned about the further progression of the osteophyte and its clinical implication.
