The degree of cartilage degeneration assessed intraoperatively may not be sufficient as a criterion for patellar resurfacing in total knee arthroplasty (TKA). However, single-photon emission tomography/computed tomography (SPECT/CT) is useful for detecting osteoarthritic involvement deeper in the subchondral bone. The purpose of the study was to determine whether SPECT/CT reflected the cartilage lesion underneath the patella in patients with end-stage osteoarthritis (OA) and whether clinical outcomes after TKA without patellar resurfacing differed according to the severity of patellofemoral (PF) OA determined by visual assessment and SPECT/CT findings. This study included 206 knees which underwent TKA. The degree of cartilage degeneration was graded intraoperatively according to the International Cartilage Repair Society grading system. Subjects were classified into four groups according to the degree of bone tracer uptake (BTU) on SPECT/CT in the PF joint. The Feller's patella score and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were assessed preoperatively and postoperative 1 and 2 years.Introduction
Methods
To calculate how the likelihood of obtaining measurable benefit from hip or knee arthroplasty varies with preoperative patient-reported scores. Existing UK data from 222,933 knee and 209,760 hip arthroplasty patients were used to model an individual’s probability of gaining meaningful improvement after surgery based on their preoperative Oxford Knee or Hip Score (OKS/OHS). A clinically meaningful improvement after arthroplasty was defined as ≥ 8 point improvement in OHS, and ≥ 7 in OKS.Aims
Methods
As life expectancy increases, the number of octogenarians requiring primary and revision total knee arthroplasty (TKA) is increasing. Recently, primary TKA has become a common treatment option in octogenarians. However, surgeons are still hesitant about performing revision TKA on octogenarians because of concerning about risk- and cost-benefit. The purpose of this study was to investigate postoperative complications and mid-term survival in octogenarians following primary and revision total knee arthroplasty (TKA). We retrospectively reviewed 231 primary TKAs and 41 revision TKAs performed on octogenarians between 2000 and 2016. The mean age was 81.9 for primary TKA and 82.3 for revision TKA (p=0.310). The American Society of Anesthesiologists (ASA) score was not different, but the age-adjusted Charlson comorbidity index was higher in revision TKA (4.4 vs. 4.8, p=0.003). The mean follow-up period did not differ (3.8 vs. 3.5 years, p=0.451). The WOMAC scores and range of motion (ROM) were evaluated. The incidence of postoperative complication and survival rate (end point; death determined by telephone or mail communication with patient or family) were investigated.Background
Methods
The purpose of the present study was to evaluate the intercompartmental loads with a sensor placed on implants after conventional gap balancing during total knee arthroplasty (TKA) with a tensiometer. Fifty sensor-assisted TKA procedures were performed prospectively between August and September 2018 with a cruciate-retaining prosthesis. After applying a modified measured technique, conventional balancing between the resected surfaces was achieved. The equal and rectangular flexion–extension gaps were confirmed using a tensiometer. Then, the load distribution was evaluated with a sensor.Purpose
Methods
Long-term clinical and radiographic results and survival rates were compared between closed-wedge high tibial osteotomy (HTOs) and fixed-bearing unicompartmental knee arthroplasty (UKA) in patients with similar demographics. Sixty HTOs and 50 UKAs completed between 1992 and 1998 were retrospectively reviewed. There were no significant differences in preoperative demographics. The mean follow-up period was 10.7 ±5.7 years for HTO and 12.0 ±7.1 years for UKA (n.s.). The Knee Society knee and function scores, WOMAC, and range of motion (ROM) were investigated. The mechanical axis and femorotibial angle were evaluated. Kaplan–Meier survival analysis was performed (failure: revision to TKA), and the failure modes were investigated.Purpose
Methods
The purpose of this study was to compare intercompartmental loads and the proportion of knees with unbalanced loads after tensiometer-assisted balancing (TAB) between cruciate retaining (CR) and posterior stabilized (PS) total knee arthroplasty (TKA). Forty-five CR and 45 PS TKAs using a single prosthesis were prospectively evaluated. The intercompartmental loads in 10°, 45°, and 90° of knee flexion after TAB were evaluated; the proportions of load imbalance (medial load – lateral load >15 lbs) in each flexion angle after TAB were investigated. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of TAB were calculated, with the sensor-balanced loads considered the reference standard.Purpose
Materials and Methods
As the number of primary or revision TKA with stem extension cases are growing simultaneously, the number of periprosthetic fracture in these cases has also increased accordingly. However, there have been few reports on the classification and treatment of periprosthetic fracture following stemmed TKA and lack of information about the treatment outcome. The purposes of this study were 1) to demonstrate classification and management of periprosthetic fractures after stemmed TKA and 2) to report treatment outcome after the periprosthetic fractures. This retrospective study included 17 knees (15 patients) with an average age of 69.7 years. All cases were revision TKA cases, and there were 13 female and 2 male patients. The patients were treated nonoperatively or underwent operation by orthopedic principle. The period of union was evaluated by confirming the formation of callus crossing fragments in radiographs. We reviewed the complications and functional outcomes after treatment of periprosthetic fracture following revision TKA by assessing FF, FC and scoring WOMAC and KSS.Background
Materials and Methods
The purpose of the present study was to compare the clinical and radiographic results after TKA using a patellofemoral design modified prosthesis and its predecessor. The other purpose was to investigate whether the use of the recent prosthesis increase the risk of posterior tibial cortex injury or patellar fracture. The clinical and radiographic results of 300 knees which underwent TKA using the Attune®prosthesis (group A) were compared with those in a paired match-control group who underwent TKA using the P.F.C. Sigma® prosthesis (group B). The preoperative demographic data between the 2 groups did not differ significantly. The WOMAC, Feller and Kujala scores, and range of motion (ROM) were compared. The minimal distance between the tibial component stem to posterior tibial cortex, and the remnant patella thickness were compared.Objective
Materials and Methods
Joint line, patellar height and posterior condylar offset (PCO) are related to functional outcome such as stability and range of motion after revision total knee arthroplasty (TKA). The purpose of this study was (1) to determine whether revision TKA can restore the joint line, patella height and condylar offset after surgery, and (2) to assess factors associated with failed restoration. We retrospectively reviewed 27 consecutive patients who underwent revision TKA. Among 27 patients, 11 patients had two-stage revision TKA due to periprosthetic joint infection while 14 patients underwent revision TKA due to aseptic loosening. In addition, there were 2 patients who had traumatic event causing a periprosthetic fracture which led to revision TKA. The joint line was measured using the distance from the adductor tubercle of the femur to the most distal portion of the medial femoral component on knee anterior-posterior radiographs. Patella height was assessed using the Caton-Deschamps method. In addition, PCO were measured relative to the tangent of the posterior cortex of the femur using knee lateral radiograph. All parameters were compared between pre- and postoperative radiographs after revision TKA.Background
Materials and Methods
The correct anteversion of the acetabular cup is critical to achieve optimal outcome after total hip arthroplasty. While number of method has been described to measure the anteversion in plane anteroposterior and lateral radiograph, it is still controversial which method provides best anteversion measurement. While many of the previous studies used CT scan to validate the anteversion measured in plane anteroposterior radiograph, this may cause potential bias as the anteversion measured in CT scan reflects true anteversion while the anteversion measurement methods in plane radiograph are design to measure the planar anteversion. Thus, in the current study, we tried to find the optimal anteversion measurement method free from the previously described bias. Custom made cup model was developed which enables change in anteversion and inclination. Simple radiograph was taken with the cup in 10° to 70° degree of inclination at 10° increments and for each inclination angle, anteversion was corrected from 0° to 30° at 5° increments. The radiograph was taken with the beam directed at the center of the cup (mimicking hip centered anteroposterior radiograph) and at 9cm medial to the cup (mimicking pelvis anteroposterior radiograph). The measurements were done by two orthopaedic surgeons using methods described by 1) Pradhan et al, 2) Lewinak et al, 3) Widmer et al, and 4) Liaw et al. For each measurements, the anteversion were compared with the actual anteversion.Introduction
Material and method
Unicompartmental Knee Arthroplasty (UKA) has been indicated for inactive elderly patients over 60, but for young and active patients less than 60 years old, it has been regarded as a contraindication. The purpose of this study is to evaluate the usefulness of UKA performed on young Asian patients under 60 years of age by analyzing clinical outcomes, complications and survival rate. The subjects were 82 cases, which were followed up for at least 5 years (from 5 to 12 years). Only Oxford phase III® (Biomet Orthopedics, Inc, Warsaw, USA) prosthesis was used for all cases. The clinical evaluation was done by the range of motion, Knee society score (KSS), WOMAC score. The radiographic evaluation was performed on weight bearing long-leg radiographs, AP and lateral view of the knee and skyline view of the patella. The survival rate was estimated by Kaplan-Meier survival analysis.Purpose
Materials and Methods
Children treated for osteosarcoma around the knee often have
a substantial leg-length discrepancy at skeletal maturity. The aim
of this study was to investigate the results of staged skeletal
reconstruction after a leg lengthening procedure using an external
fixator in these patients. We reviewed 11 patients who underwent staged reconstruction with
either an arthroplasty (n = 6) or an arthrodesis (n = 5). A control
group of 11 patients who had undergone wide excision and concurrent
reconstruction with an arthroplasty were matched for gender, location,
and size of tumour. We investigated the change in leg-length discrepancy,
function as assessed by the Musculoskeletal Tumor Society Scale
(MSTS) score and complications.Aims
Patients and Methods
Our aim was to investigate the predictive factors for the development
of a rebound phenomenon after temporary hemiepiphysiodesis in children
with genu valgum. We studied 37 limbs with idiopathic genu valgum who were treated
with hemiepiphyseal stapling, and with more than six months remaining
growth at removal of the staples. All children were followed until
skeletal maturity or for more than two years after removal of the
staples.Aims
Patients and Methods
Deformity of knee joint causes deviation of mechanical axis in the coronal plane, and the mechanical axis deviation also could adversely affect biomechanics of the ankle joint as well as the knee joint. Particularly, most of the patients undergoing total knee arthroplasty (TKA) have significant preoperative varus malalignment which would be corrected after TKA, the patients also may have significant changes of ankle joint characteristics after the surgery. This study aimed 1) to examine the prevalence of coexisting ankle osteoarthritis (OA) in the patients undergoing TKA due to varus knee OA and to determine whether the patients with coexisting ankle OA have more varus malalignment, and 2) to evaluate the changes of radiographic parameters for ankle joint before and 4 years after TKA. We evaluated 153 knees in 86 patients with varus knee OA who underwent primary TKA. With use of standing whole-limb anteroposterior radiographs and ankle radiographs before and 4 years after TKRA, we assessed prevalence of coexisting ankle OA in the patients before TKA and analyzed the changes of four radiographic parameters before and after TKA including 1) the mechanical tibiofemoral angle (negative value = varus), 2) the ankle joint orientation relative to the ground (positive value = sloping down laterally), 3) ankle joint space, and 4) medial clear space.Introduction
Methods
Even a number of studies have reported clinical outcomes after revision total knee arthroplasty (revision TKA), little information is still available on whether outcomes of patients undergoing a revision TKA as a second stage procedure because of infected TKA are poorer than those of the patients undergoing a single-stage revision TKA because of non-infectious causes. In addition, use of various revision prostheses in most previous studies may limit solid interpretation of the outcomes after revision TKA. This study sought to determine whether outcomes in patients undergoing revision TKA due to infected TKA would be different from those in patients undergoing revision TKA due to non-infectious causes. We assessed 71 cases undergoing revision TKAs with use of a same revision system (Scorpio TS®, Stryker, Mahwah, NJ) from October 1999 to February 2012. All patients followed more than two years and mean follow-up period was 67 months (range: 24 – 168 months). Of them, thirty five patients underwent revisions due to infected TKA (group for infected TKA) while 36 patients due to non-infectious causes including loosening, wear, and/or instability (group for non-infected TKA). All patients in the group for infected TKA underwent two-stage revision surgeries while all patients in the group for non-infected TKA single stage revision surgeries. Comparative variables between two groups were preoperative range of motion (ROM) and American knee society (AKS) scores, postoperative ROM and AKS scores assessed at latest follow-up, amount of bone loss and requirement of stem assessed during the surgeries, and survival rate.Introduction
Materials and Methods
Total knee arthroplasty (TKA) is a proven treatment method for advanced knee arthritis in terms of pain relief, function restoration, and quality-of-life improvement. The TKA use has increased significantly over the past decade and the growing rate is more prominent in Asian countries. Thus, the revision TKA may also increase in recent days, which represents a burden to the national health care system. To the best of our knowledge, little information is currently available regarding the incidence and related factors of revision TKA in Asian countries on the basis of nationwide database. This study sought to find the incidence of revision TKA and related factors in South Korea using national database from 2007 to 2012. Data collected by the Health Insurance Review Agency of Korea, from 260,068 TKA patients between 2007 and 2012, were used to estimate the incidence of revision TKA according to age group, gender and hospital TKA and manufacturer prosthesis volume (i.e., the number of TKA procedures carried out at a given hospital, and the number of procedures performed using a given manufacturer's prosthesis, respectively). Age group and hospital and manufacturer volumes were categorized into three groups and TKA incidence rates were computed for groups stratified according to age, gender and hospital and manufacturer volumes.Introduction
Material and Method
A small proportion of children with Gartland
type III supracondylar humeral fracture (SCHF) experience troubling limited
or delayed recovery after operative treatment. We hypothesised that
the fracture level relative to the isthmus of the humerus would
affect the outcome. We retrospectively reviewed 230 children who underwent closed
reduction and percutaneous pinning (CRPP) for their Gartland type
III SCHFs between March 2003 and December 2012. There were 144 boys
and 86 girls, with the mean age of six years (1.1 to 15.2). The
clinico-radiological characteristics and surgical outcomes (recovery
of the elbow range of movement, post-operative angulation, and the
final Flynn grade) were recorded. Multivariate analysis was employed
to identify prognostic factors that influenced outcome, including
fracture level. Multivariate analysis revealed that a fracture below
the humeral isthmus was significantly associated with poor prognosis
in terms of the range of elbow movement (p <
0.001), angulation
(p = 0.001) and Flynn grade (p = 0.003). Age over ten years was also
a poor prognostic factor for recovery of the range of elbow movement (p
= 0.027). This is the first study demonstrating a subclassification system
of Gartland III fractures with prognostic significance. This will
guide surgeons in peri-operative planning and counselling as well
as directing future research aimed at improving outcomes. Cite this article:
Cancellous allograft bone chips are commonly
used in the reconstruction of defects in bone after removal of benign tumours.
We investigated the MRI features of grafted bone chips and their
change over time, and compared them with those with recurrent tumour.
We retrospectively reviewed 66 post-operative MRIs from 34 patients
who had undergone curettage and grafting with cancellous bone chips
to fill the defect after excision of a tumour. All grafts showed
consistent features at least six months after grafting: homogeneous
intermediate or low signal intensities with or without scattered
hyperintense foci (speckled hyperintensities) on T1 images; high
signal intensities with scattered hypointense foci (speckled hypointensities)
on T2 images, and peripheral rim enhancement with or without central
heterogeneous enhancements on enhanced images. Incorporation of
the graft occurred from the periphery to the centre, and was completed
within three years. Recurrent lesions consistently showed the same signal
intensities as those of pre-operative MRIs of the primary lesions.
There were four misdiagnoses, three of which were chondroid tumours. We identified typical MRI features and clarified the incorporation
process of grafted cancellous allograft bone chips. The most important
characteristics of recurrent tumours were that they showed the same
signal intensities as the primary tumours. It might sometimes be
difficult to differentiate grafted cancellous allograft bone chips
from a recurrent chondroid tumour. Cite this article:
A total of 187 patients with primary osteoarthritis
(OA) of the knee undergoing total knee replacement (TKR) were randomly
divided into two groups, one of which underwent synovectomy. The
patients and assessors were blinded to the randomisation both before
and after surgery. The duration of surgery, hospitalisation period,
concealed bleeding, drainage volume, blood transfusion rate and
range of movement of the knee at three days after the operation
were analysed. Patients were followed up at four weeks and 12 months
after their operation, and a visual analogue score (VAS) for pain,
Knee Society score (KSS) and a patellar ballottement test were compared
between the groups. The mean amount of concealed bleeding was higher in the synovectomy
group compared with the control group (1.24 l (0.08 to 3.28) Cite this article:
A seventy-five-year-old female patient presented with pain and deformity of her left leg of three days duration. Hybrid THRA has been done 11 years ago at her left hip for the treatment of osteoarthritis. Massive osteolysis and pathologic fracture were observed on plain radiograph (Fig. 1). Revision THRA using an allograft prosthesis composite (APC) was planned for solution of extensive bone loss of the proximal femur. Surgical exposure was performed through extended trochanteric osteotomy with the patient supine. Step-cut osteotomy was done at the remained proximal part of host femur to make match with the distal part of APC. Meticulous removal of granulation tissues and remaining cement was done. As Acetabular cup was stable, 60 mm sized high-walled polyethylene liner was exchanged. Calcar reconstruction prosthesis was cemented into a proximal femoral allograft measuring 15 cm and cement at the vicinity of the step-cut osteotomy was removed for later bony union at interface. After solid fixation of APC with cement, the distal half of APC was cemented with the host femur. Step-cut osteotomy was wired and autogenous bone grafts from the greater trochanter were added at the interface. Leg length and stability were rechecked using a standard necked 28 mm metal head and reduction was done stably. Greater trochanter was fixed over the trimmed proximal allograft with multiple wiring and paper-thin host femur was enveloped around the femoral allograft using absorbable sutures. Following insertion of the closed suction drainage drains, closure was done as routine fashion and healing of the wound was uneventful (Fig. 2). An abduction brace was applied post operatively for a period of four weeks. Crutch walking with partial weight bearing was started at four weeks and crutch protection was applied for a period of six months. Incorporation of allograft with the host bone was observed on two-year follow-up radiographs. At seven-year follow-up, the patient walks well with a mild limp, and Harris score is 90. We report on a seven-year follow-up case of revision THRA with APC with references (Fig. 3).
The purpose of this study was to determine whether the patient's perceived outcome and speed of recovery differs between a posterior cruciate ligament (PCL) substituting (cam-post type) and PCL sacrificing (ultracongruent polyethylene) total knee arthroplasty (TKA). Thirty eight patients (mean age, 65 years) underwent bilateral TKA using a PCL substituting and a PCL sacrificing prosthesis on each side. At each follow-up, the stability of anteroposterior and mediolateral laxity using stress radiographs, range of motion, quadriceps muscle power recovery using isokinetic dynamometer and radiographs were evaluated. At the 1-year evaluation, we asked, “Which is your better knee overall?” to determine the patients' preferences.Introduction
Methods
The posterior-stabilized knee prosthesis is designed specifically to provide the posterior stability to a knee arthroplasty when PCL is deficient or has to be sacrificed. Posterior dislocation of such prosthesis is rare but dreaded complication. There are several causes of postoperative dislocation such as malposition of the prosthesis, preoperative valgus deformity, a defect of the extensor mechanism and overwidening of the flexion gap. Posterior-stabilized rotating-platform mobile-bearing knee implants have been widely used to further improve the postoperative range of motion by incorporation of the post and cam mechanism to improve the posterior roll back during flexion and to overcome the wear and osteolysis problems due to significant undersurface micromotion of posterior-stabilized fixed-bearing knees. But, spin-out or rotatory dislocation of the polyethylene insert can occurs as result of excessive rotation of the rotating platform accompanied by translation of the femur on the tibia after mobile-bearing total knee arthroplasty, but that is very rare. Here, authors describe an unusual case of acute 180° rotatory dislocation of the rotating platform after posterior dislocation of a posterior-stabilized mobile-bearing total knee arthroplasty. A 71-year-old male with knee osteoarthritis underwent a TKRA using posterior-stabilized mobile-bearing prosthesis. The posterior dislocation of the total knee arthroplasty occurred 5 weeks postoperatively(Fig. 1). We underwent closed reduction of posterior dislocated total knee arthroplasty resulting in a complete 180° rotatory dislocation of the rotating platform (Fig. 2). He was treated with open exploration and polyethylene exchange with a larger component. This case illustrates that dislocation of a posterior-stabilized mobile-bearing total knee arthroplasty can occur with valgus laxity, cause 90° spin-out of the polyethylene insert and closed reduction attempts may contribute to complete 180° rotatory dislocation of the rotating platform. Special attention needs to be paid to both AP and lateral view to ensure that the platform is truly reduced and not just rotated 180° as was in this case.
The long-term outcome and survivorship of TKA in Asian countries have been reported to be excellent, comparable to Western countries. However, increased knee flexion is required for many daily activities in Asian cultures, which remains a major problem to be resolved. High-flexion TKA designs have been introduced to improve flexion after TKA and to allow a high degree of flexion in a safe manner. However, several biomechanical studies have shown that high-flexion designs have a greater risk for the loosening of the femoral component compared to the conventional TKA designs. We evaluated the implant survival and the mid-term clinical and radiological outcomes of Asian patients who had undergone high-flexion TKA and assessed whether high-flexion activities increased the risk of premature failure. We prospectively followed 72 Nexgen LPS-flex fixed TKA in 47 patients implanted by a single surgeon between March 2003 and September 2004. Five patients (6 knees) expired during follow-up. A Kaplan-Meier survivorship analysis using revision surgery as the end point was used to determine the probability of survival for the cohort and the equality of survival between two subgroups who could perform high-flexion activities or not. Median follow-up was 6.5 (0.9–8.6) years. Twenty-five patients (33 knees) received a revision for aseptic loosening of the femoral component at a mean of 3.5 years (range, 0.9–7.8 years). According to the Kaplan-Meier survivorship analysis, the probabilities of survival without revision for aseptic loosening are 66.7% and 51.8% at 5 and 8 years, respectively. The 8-year cumulative survivorship is lower (30.6%) when squatting, kneeling, or sitting cross-legged could be achieved than if none of these activities were possible (78.3%). In the surviving knees, non-progressive radiolucent lines were observed around the femoral component of 12 patients (15 knees) and one tibial component. The overall mid-term high-flex implant survival of our Asian cohort is lower than that of the conventional and other high-flexion designs. This unacceptable high rate of femoral component loosening is strongly associated with postoperative high flexion activities.
The purpose of this study was to validate the usefulness of SPECT/CT as an evaluation method for determining treatment and prognosis for patellofemoral cartilage lesions, based on MRI and arthroscopic findings. From August 2009 to February 2010, SPECT/CT was performed on 80 patients (24 male and 56 female, average 53.3 years old) with chronic anterior knee pain who had no degenerative changes or patellar malalignment on plain radiographs. Radioisotope uptake findings on patellofemoral joint from SPECT/CT were classified into three grades by one nuclear medicine specialist. In the patients who demonstrated poor improvements after conservative treatments, MRI and arthroscopy were performed. Patellofemoral cartilage conditions under arthroscopic finding (ICRS grades) were compared with SPECT/CT grading. In all cases, there were increased uptakes on patellofemoral joints. Eighteen cases showed low uptake (Group 1), 22 cases showed medium uptake (Group 2) and 40 cases high uptake (Group 3). At the follow-up examination after mean 1.7 months, 16 cases of Group 1 (89%), 14 cases of Group 2 (64%) and 28 cases of Groups3 (70%) responded positively to the conservative treatments. For those 22 cases showing poor improvement, MRI and arthroscopy were done. Damage or thinning of patellofemoral cartilage, subchondral cyst, edema and fissuring were observed in every case that underwent MRI. Every arthroscopic case was found that there was patellofemoral cartilage damage. Each of ICRS grade I and grade II was found in 2 cases from Group 1. Two cases of grade II, 4 cases of grade III, and 2 cases of grade IV were found in Group 2. Two cases of grade II, 4 cases of grade III, and 6 cases of grade IV were found in Group 3. There was significant difference in the success rate of conservative treatment between SPECT/CT grade 1 and 2 or 3. And there was significant association between SPECT/CT grade and ICRS grade (P=0.034). SPECT/CT could be a useful modality in determining the treatment and prognosis for patellofemoral cartilage lesions compared with MRI and arthroscopic findings.
Using Altman’s nomogram, the sample size was calculated to be 85 for a power of 90%, with an α significance level of 0.05. Using this database, digital radiographs were assessed using the institution’s PACS system. Pre-operative and follow-up skyline radiographs following Jones et al’s (1993) patellofemoral scoring system were examined by four assessors utilising Jones’ patellofemoral scoring system. In addition, in cases where patellofemoral joint changes were evident, each assessor acknowledged whether this involved the medial, lateral or bilateral aspects of the patellofemoral joint. Intra-observer reliability was made comparing the four assessors. Statistical analysis was performed, using the Statistical Package for the Social Sciences (SPSS) 16.0 for Windows (SPSS Inc, Chicago, Illinois). In order to determine whether changes in patellofemoral joint status related to patients function or quality of life, the difference in OKS and SF-12 from pre-operative to the follow-up period was assessed.
There has been debate about the role of unicompartmental knee replacement in the presence of radiologically identifiable degenerative changes of the patellofemoral joint. We studied 195 knees in 163 patients in whom an Oxford unicompartmental knee replacement had been performed for medial osteoarthritis between January 2004 and July 2007. The mean age of the patients was 66 years (51 to 93). The degree of degenerative change of the patellofemoral joint was assessed using Jones’ criteria. Functional outcome was assessed at a mean of 3.4 years (2 to 7) post-operatively, using the Oxford knee score and the Short-form 12 score. Degenerative changes of the patellofemoral joint were seen pre-operatively in 125 knees (64%) on the skyline radiographs. There was no statistically significant difference in the Oxford knee or Short-form 12 scores between those patients who had patellofemoral osteoarthritis pre-operatively and those who did not (p = 0.22 and 0.54, respectively). These results support the opinion expressed at the designer’s hospital that degenerative changes of the patellofemoral joint in isolation should not be considered to be a contraindication to medial Oxford unicompartmental knee replacement.
We present the results of 90 consecutive children with displaced fractures of the forearm treated by elastic stable intramedullary nailing with a mean follow-up of 6.6 months (2.0 to 17.6). Eight (9%) had open fractures and 77 (86%) had sustained a fracture of both bones. The operations were performed by orthopaedic trainees in 78 patients (86%). All fractures healed at a mean of 2.9 months (1.1 to 8.7). There was one case of delayed union of an ulnar fracture. An excellent or good functional outcome was achieved in 76 patients (84%). There was no statistical difference detected when the grade of operating surgeon, age of the patient and the diaphyseal level of the fracture were correlated with the outcome. A limited open reduction was required in 40 fractures (44%). Complications included seven cases of problematic wounds, two transient palsies of the superficial radial nerve and one case each of malunion and a post-operative compartment syndrome. At final follow-up, all children were pain-free and without limitation of sport and play activities. Our findings indicate that the functional outcome following paediatric fractures of the forearm treated by elastic stable intramedullary nailing is good, without the need for anatomical restoration of the radial bow.
Primary total knee arthroplasty is associated with considerable blood loss, and allergenic blood transfusions are frequently necessary. Because of the cost and risks of allogenic blood transfusions, the autologous drainage blood reinfusion technique has been developed as an alternative. A number of studies have compared reinfusion techniques with standard suction drainage, but few reports compared with no drain use. We analyzed early results after primary total knee arthroplasty using autologous drainage blood reinfusion and no drain. We selected 30 patients who underwent primary total knee arthroplasty using no drain between November 2005 and March 2006 and matched for age and gender with 30 patients who underwent primary total knee arthroplasty using autologous drainage blood reinfusion technique between January 2003 and October 2005. All operations were done under pneumatic tourniquet and meticulous hemostasis was performed after deflation of the tourniquet. We have retrospectively reviewed the preoperative data (age, gender, body mass index, diagnosis, history of the knee surgery, infection and anticoagulant therapy, and medical cormorbidities) and the postoperative data (hemoglobin, hematocrit and platelet during hospitalization, the amount of allogenic blood transfusion and narcotics, complications, rehabilitation process, and clinical scores). All preoperative and postoperative variables except the postoperative second and seventh days hemoglobin and 2nd day hematocrit showed no significant differences between two groups. The hemoglobin and hematocrit also showed no significant differences at the postoperative fourteenth day. The autologous drainage blood reinfusion method in primary total knee arthroplasty does not have significant clinical benefit over no-drain method with regards to allogenic blood transfusions, narcotics uses, the incidence of complications and rehabilitation processes.
‘Tribology’ is derived from the Greek word “tribos” and means the “science of rubbing”. Friction, lubrication, and wear mechanism in the common English language means the precise field of interest of tribology. Wear of PE insert has often been reported in TKA to be primary causes of complications and failure. As a friction, the wear that occurs in TKA is system properties rather than intrinsic material properties and is therefore affected by multiple variables such as design, material properties, duration and alignment. The contact area on each condyles varies from about 150 mm2 for moderate to high-conformity knees in flexion, down to 30 mm2 for low-conformity. The corresponding maximum compressive pressure in activity is 10 to 50 MPa, which favor fatigue and deformation of UHMWPE (yield stress: 15MPa). In contrast, fully conforming mobile bearing knees have contact area of at least 300 mm2 on each condyles, giving maximum pressure of only 5 MPa. There are several mechanisms whereby small PE particles are released in TKA. Some of these mechanisms are fatigue processes requiring numerous cycles of sliding. Multidirectional sliding is more damaging than sliding in same direction. The wear mechanisms in TKA are as follows:
Adhesive wear Abrasive wear (2-body, 3-body) Third body wear Corrosion wear Fatigue wear (delamination): the most destructive of all wear mechanism There have been a number of published studies on the in vivo wear measured on retrieved total knee bearings. These studies indicated more clinical wear on the medial side. Patterns of wear varied greatly among individual knees; a majority showed very similar extents of wear on the medial and lateral sides, however there were cases with significantly more wear on one condylar articulation than the other. Evidence of edge loading was common and seen most frequently in the central zone of the medial condylar area.
Wound complication including superficial infection is a concern after total knee arthroplasties (TKA) in diabetics. However, influence of glycoregulation before TKA has not been investigated in relationship to wound healing. Our hypothesis was that glycated hemoglobin (HbA1C), since it reflects long-term regulation of blood glucose, might be associated with incidence of wound complications after TKA in diabetic patients. We retrospectively reviewed 167 TKAs performed in 115 patients with diabetes mellitus between January 2001 and March 2007. All patients were diagnosed as type II DM and osteoarthritis. A wound complication was defined as a hematoma, bulla, drainage or superficial infection. Stepwise multivariate logistic regression was used to identify which variables had a significant effect on the risk of wound complications. Variables considered were age, gender, body mass index, histories of previous knee surgery, comorbidities, duration of diabetes, the methods of diabetes treatment, complications of diabetes, preoperative HbA1c level, operation time, antibiotics-impregnated cement use, the amount of blood transfusion, and postoperative blood glucose level. The overall incidence of wound complications was 6.6% (n=11) including superficial infection in 1.8% (n=3), hematoma or bullae in 3.6% (n=6), and drainage in 1.8% (n=3). There were seven cases (4.2%) of deep infection. A multivariate logistic regression revealed that independent risk factors for the development of wound complications were preoperative HbA1C ≥ 8% (odds ratio 6.074, 95% confidence interval 1.119–32.971) and operation time (odds ratio 1.013, 95% confidence interval 1.000–1.026). Poorly controlled hyperglycemia before surgery may increase the incidence of wound complications among diabetic patients receiving total knee arthroplasties. The correlation of glycemic control and wound complications may assist in the preoperative evaluation and selection of time for surgery.
We performed a systematic review of the optimal management of septic arthritis in children as recommended in the current English literature using MEDLINE, EMBASE, CINAHL, the Cochrane Library and reference lists of retrieved articles without date restrictions up to 31 January 2009. From 2236 citations, 227 relevant full-text articles were screened in detail; 154 papers fulfilled the inclusion criteria, from which conclusions were drawn on the management of infected joints in children. Our review showed that no single investigation, including joint aspiration, is sufficiently reliable to diagnose conclusively joint infection. The roles of aspiration, arthrotomy and arthroscopy in treatment are not clear cut, and the ideal duration of antibiotic therapy is not yet fully defined. These issues are discussed. Further large-scale, multi-centre studies are needed to delineate the optimal management of paediatric septic arthritis.
We have examined the results obtained with 72 NexGen legacy posterior stabilised-flex fixed total knee replacements in 47 patients implanted by a single surgeon between March 2003 and September 2004. Aseptic loosening of the femoral component was found in 27 (38%) of the replacements at a mean follow-up of 32 months (30 to 48) and 15 knees (21%) required revision at a mean of 23 months (11 to 45). We compared the radiologically-loose and revised knees with those which had remained well-fixed to identify the factors which had contributed to this high rate of aseptic loosening. Post-operatively, the mean maximum flexion was 136° (110° to 140°) in the loosened group and 125° (95° to 140°) in the well-fixed group (independent These implants allowed a high degree of flexion, but showed a marked rate of early loosening of the femoral component, which was associated with weight-bearing in maximum flexion.
