Osteoarthritis (OA) is an inflammatory degenerative disease that affects every fourth person with irreversible damage to the articular. Mesenchymal stem cells (MSCs) have been shown to affect host cells by paracrine stimulation in regenerative environments. Here we apply hyaluronic acid (HA), an essential part of the extracellular matrix in cartilage, for MSC immobilization. The aim was to investigate long-term MSC survival and paracrine effect on chondrocytes in an inflammatory co-culture environment. We hypothesized that MSCs immobilized in a HA hydrogel could provide a long-term immunomodulatory effect on chondrocytes in vitro. Human MSCs were seeded in a HA hydrogel and co-cultured with non-osteoarthritic human chondrocytes in biphasic wells inhibiting cellular contact. An inflammatory environment was induced by IL1-beta and compared with standard culture medium. Relative gene expressions of collagen types I, II and X, aggrecan, SOX9, MMP-13 and ADAMTS-5) were examined at day 3,7,14 and 28. Significant up-regulation of SOX9 at day 7, 14 and 28 and a significant down-regulation of ADAMTS-5 (day 14 and 28) was observed with co-culture of HA-immobilized MSCs and MSCs compared with controls with or without HA (without MSCs)No changes in expression was observed for aggrecan and collagen type 1. We showed that MSC affect the expression of SOX9 and ADAMTS-5 in a paracrine manner when co-cultured with chondrocytes in an inflammatory environment. MSCs immobilized in HA hydrogels survived and were contained in the hydrogel for up to 28 days. This suggests that HA-immobilized MSCs could potentially be used as adjuvant treatment of OA.

Introduction

The demands placed upon joint surgeons are perhaps greatest when treating the revision arthroplasty patient, who present with complications demanding skill in diagnosis and evaluation, interpersonal communication and the technical aspects of the revision procedure. However, little information exists identifying which specific tasks in revision arthroplasty are most difficult for surgeons to master, and whether the greatest challenges arise from clinical, cognitive or technical facets of patient treatment. This study was undertaken to identify which tasks associated with revision total knee replacement (TKR) are perceived as most challenging to young surgeons and trainees to guide future efforts in surgical training and curriculum development.

Introduction

Reverse Total Shoulder Arthroplasty (rTSA) is an efficient treatment, to relieve from pain and to increase function. However, scapular notching remains a serious issue and post-operative range of motion (ROM) presents many variations. No study compared implant positioning, different implant combinations, different implant sizes on different types of patient representative to undergo for rTSA, on glenohumeral ROM in every degree of freedom.

Introduction

While total hip arthroplasty is considered to be one of the most cost-effective medical interventions, the total cost of care for a population patients treated by THR can present a significant burden on the payer, whether it be an employer, private insurer or government. Data on the true cost of care has rarely been made available to the treating physician. Such lack of information makes comprehensive management difficult. Bundled payment models of care require knowledge of all costs associated with the care of our patients and opens new opportunity for analysis to improve management and outcomes. The current study assess the influence of surgical technique on total cost of care for total hip arthroplasty.

BACKGROUND

Ideal treatment of displaced femoral neck fragility fractures in the previously ambulatory patient remains controversial. Treating these patients with total hip arthroplasty has improved patient reported outcomes and reduced rates of revision surgery compared to those treated with hemiarthroplasty. However, possible increased risk of dislocation remains a concern with total hip arthroplasty.

The anterolateral and direct anterior approaches to total hip replacement have been applied in the femoral neck fracture population to minimize dislocation rates. However, the anterolateral approach has been associated with abductor injury and increased rates of heterotopic ossification while the anterior approach has been associated with peri-prosthetic femur fracture, lateral femoral cutaneous nerve injury, and wound complications. The Supercapsular Percutaneously Assisted (SuperPATH) approach was developed to minimize disruption of the capsule and short-external rotators in an effort to reduce the risk of dislocation and assist in quicker recovery in the elective hip arthroplasty setting. To achieve this, the SuperPATH technique allows the femur to be prepared in situ and the acetabulum to be reamed percutaneously once the femoral head is removed.

This study investigates the post-operative time to ambulation, length of stay, discharge destination, and early dislocation rate of previously ambulatory patients with a displaced femoral neck fragility fracture that were treated with a total hip arthroplasty via the SuperPATH technique.

BACKGROUND

The need for post-operative manipulation under anesthesia (MUA) for stiffness after primary total knee arthroplasty is a frustrating complication that can lead to suboptimal outcomes if range-of-motion to a functional level is not regained. Implant morphology and kinematics, PCL imbalance, and soft-tissue balancing can all contribute to post-operative stiffness. Utilization of total knee arthroplasty components that replicate the native knee's medial ball and socket kinematics may lead to easier maintenance of flexion post-operatively compared to conventional components.

INTRODUCTION

Patients less than 60 years old have been reported to have a higher risk of revision following total hip arthroplasty (THA) than older patient cohorts, possibly to due higher activity, a higher incidence of deformity and greater probability of prior surgery. Ceramic-on-ceramic bearing surfaces have been proposed for use in young and active individuals due to their low wear, low risk of adverse biologic reaction, and long-term survivorship. We assessed the clinical results and long-term survivorship of uncemented ceramic-on-ceramic THA in a young patient population.

INTRODUCTION

The direct anterior approach to THR has become an increasingly popular minimally-invasive technique in an effort to minimize dislocation risk, facility early recovery, and diminish soft tissue injury. However, it has been associated with unique complications including intraoperative femur fracture, cutaneous nerve palsy, stem subsidence, and wound healing complications. These risk of these complications have been documented to be more likely in the surgeon's early experience with the approach. The minimally-invasive Supercapsular Percutaneous-Assisted (SuperPATH) technique was developed to minimize capsular and short-external rotator injury, minimize dislocation risk, and provide an easier transition from the standard posterior approach.

Introduction

Orientation of the acetabular component in total hip arthroplasty has been shown to influence component wear, stability, and impingement. Freehand placement of the component can lead to widely variable radiographic outcomes. Accurate abduction, in particular, can be difficult in the lateral decubitus position due to limited ability to appreciate and control positional obliquity of the pelvis. A CT-based mechanical navigation device has been shown to decrease cup placement error. This is an independent report of a single-surgeon's radiographic results using the device to control cup abduction.

Bone grafts are crucial for the treatment of bone defects caused by tumor excision. The gold standard is autograft but their availability is limited. Allografts are an alternative, but there is a risk of rejection by the immune system. The tissue engineering field is trying to develop vascularized bone grafts, using innovative biomaterials for surgery applications. While the gold standard in bone graft in dentistry is the use of decellularized bovine bone particles (Bio-Oss®), our work has produced a polysaccharide-based composite matrix (composed of PUllulan, DextraNand particles of HydroxyApatite (PUDNHA), as a new scaffold for promoting bone formation and vascularization of the tissue. In the context of bone tissue regeneration, the function of osteoblast and endothelial cells has been extensively studied, while the impact of osteocytes has been regarded as secondary. Nonetheless, the osteocytes represent 90–95% of bone cells and are responsible for orchestration of bone remodeling.

Here, we propose an original method to analyze the interaction between bone and biomaterials, after in vivo implantation of the matrix PUDNHA in an experimental sheep model. Our objectives are to analyze the network established by osteocytes in the newly formed tissue induced by the matrix, as well as their interactions with the blood vessels.

Sheep have been implanted with the Bio-Oss® or the PUDNHA using the sinus lift technique. After 3 (3M) and 6 months (6M), the animals were euthanazied and the explants were fixed, analyzed by X-ray, embedded in Methylmetacrylate/Buthylmetacrylate and analyzed histologically by Trichrome staining. Thereafter, the samples (n=3/group) were polished using different sand papers. A final polish was realized using a 1µm Diamond polishing compound. The blocks were incubated 10 or 30s with 37% phosphoric acid to remove the mineral on the surface, then dipped in 2.6% sodium hypochlorite to remove the collagen. The samples were air dried overnight, metallized with Gold palladium the following day, before being imaged with a SEM.

As expected, PUDNHA activates bone regeneration in this sinus lift model after 3M and 6M. X-ray analysis and histological data revealed more bone regeneration at 6M versus 3M in both groups. With this acid eching technique, we were able to visualize the interface of bone with the biomaterials. This treatment coupled with SEM analysis, confirmed the increase of bone formation with time of implantation in both groups. In addition, SEM images revealed that osteocyte alignment and their network were different in the new regenerated bone compared to the host bone. Moreover, images showed the direct contact of the osteocytes with the blood vessels formed in the new regenerated bone.

This acid eching technique can be useful in the field of biomaterials to see the relationship between cells, blood vessels and the material implanted and understand how the new bone is forming around the different biomaterials.

INTRODUCTION

Evolving payment models create new opportunities for assessment of patient care based on total cost over a defined period of time. These models allow for analyses of economic data that was previously unavailable and well beyond our familiar studies which typically include length of stay, surgical complications, and post-operative clinical and radiographic assessments. In the United States, the new Federal program entitled TheBundled Payment for Care Initiative created new opportunities for the assessment of surgical interventions. The purpose of the reported study was to assess the total reimbursement for care as a function of surgical technique in primary total hip arthroplasty (THA).

INTRODUCTION

Young patients (< 50 years old) have been reported to have a higher risk of revision following total hip arthroplasty (THA) than older patient cohorts, possibly to due higher activity, a higher incidence of deformity and greater probability of prior surgery. Ceramic-on-ceramic bearing surfaces have been proposed for use in young and active individuals due to their low wear, low risk of adverse biologic reaction, and long-term survivorship. We assessed the clinical results and long-term survivorship of uncemented ceramic-on-ceramic THA in a young patient population.

Introduction

Cup malposition in hip arthroplasty and hip resurfacing is associated with instability, accelerated wear, and the need for revision. A recent study measuring cup orientation on conventional radiodiographs demonstrated an incidence of cup malpositioning of 50% according to the safe zone that they defined 1,2. A prior study of 105 conventionally placed cups using CT demonstrated a cup malpositioning incidence of 74%3. The current study similarly assesses the variation in cup position using conventional techniques as measured by CT.

Introduction

Adverse Local Tissue Reactions (ALTR) have been reported in association with both wear and corrosion. Tissue reactions have been reported in association with corrosion at CoCr head-CoCr neck, CoCr head-TiAl6V4 neck, and CoCr modular neck on beta-titanium (TMZF) stem junctions. The current abstract reports on 3 cases of ALTR in association with CoCr modular necks on convention titanium (TiAl6V4) stem junctions.

Case 1. A 67 year old male (87 kg, 1.73 m, BMI 29.1) presented with new onset hip irritation 11 months after surgery. Radiographs show no abnormalities. Further investigation revealed the following: ESR = 95, CRP = 5, Cr level = 1.0, Co level = 4.1, leukocyte transformation testing = highly reactive to nickel. Hip aspiration was culture negative with 11,250 wbc. Metal artifact reduction MR showed cystic local reaction in the region of the greater trochanter.

Case 2. A 52 year old male (89 kg, 1.83 m, BMI 26.5) presented with new onset hip irritation 30 months after surgery. Radiographs show no abnormalities. Further investigation revealed the following: ESR = 7, CRP = 5.4, Cr level = 2.1, Co level = 4.8, leukocyte transformation testing = reactive to nickel. Hip aspiration was culture negative with 3995 wbc. Metal artifact reduction MR showed cystic local reaction in the region of the iliopsoas.

Case 3. A 52 year old male (104 kg, 1.85 m, BMI 30.1) presented with new onset hip irritation 26 months after surgery. Radiographs show no abnormalities. Further investigation revealed the following: ESR = 33, CRP = 34.9, Cr level = 1.0, Co level = 3.7, leukocyte transformation testing = no reactivity to any of the biomaterials. Hip aspiration was culture negative with 3,780 wbc. Metal artifact reduction MR showed cystic local reaction in the region of the iliopsoas.

Introduction:

Young patients have been reported to have a higher risk of revision following total hip arthroplasty (THA) than older cohorts, possibly to due higher activity and a higher incidence of deformity and prior surgery. Ceramic-on-ceramic bearing surfaces have been proposed for use in young and active individuals due to their low wear, low risk of adverse biologic reaction, and long-term survivorship. We assessed the clinical results and long-term survivorship of uncemented ceramic-on-ceramic THA in a young patient population.

Purpose of the study: The purpose of this retrospective work was to analyse a series of ten patients (11 osteotomies) who underwent closed rotation osteotomy of the femur performed with an endomedullary saw and stabilized with a centromedullar locked nail. We identified the proper indications, technical aspects, clinical and radiological outcome and describe the complications of this surgical technique.

Material and method: The 11 osteotomies were performed in ten patients from January 1999 to July 2007 for post-trauma rotation defects or congenital deformity. On average the rotation defect was 33.5 (range 24–52), mainly internal rotation (10 cases versus 1 with external rotation). One female patient required a bilateral procedure in a context of congenital bilateral trochlea dysplasia. For two other patients the corrective osteotomy was associated with a lengthening procedure performed during the same operative time (totally closed operation). Clinical and radiological follow-up was available to 4 years 9 months on average (range 26–104 months). The angle corrections were determined on bone tomographs.

Results: Ten of the 11 osteotomies yielded correction to ±4° physiological values (or controlateral values if the other side was healthy) for anteversion of the femoral neck. There were no infections (bone, joint, skin, soft tissue) and not late healing or non-union. There was one transient neurological complication involving the pudendal nerve during a rotation-lengthening procedure and one bilateral fracture of the femur during a bilateral osteotomy. All patients healed within 3 to 5 months. Subjective outcome was satisfactory very satisfactory for 8 of 9 patients (one lost to follow-up) in terms of functional recovery and aesthetic aspect of the scars.

Discussion: The closed procedure for rotation osteotomy of the adult femur is a reliable, effective, safe and reproducible technique for the correction of rotation defects of the femur resulting from trauma or congenital disorders. These results can be obtained only with rigorous technique requiring experience and skill with centromedullary nailing.

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.

Purpose: The Sauvé-Kapandji procedure is often performed for the treatment of posttraumatic degeneration of the distal radioulnar joint. Few studies have been devoted specifically to the proximal stump of the ulnar after this procedure. The aim of our study was to conduct a radioclinical evaluation of the dynamics of the proximal ulnar stump.

Material and methods: This retrospective analysis involved fourteen patients (four women and ten men), mean age 48 years who underwent the procedure between January 1991 and March 2002. All presented posttraumatic degradation of the distal radioulnar joint. The operation took place twelve months after trauma on average. Mean ulnar resection was 11 mm, performed as distally as possible. The pronator quadratus was not advanced into the false joint. Pronation-supination rehabilitation exercises were instituted shortly after surgery. A static and dynamic x-rays protocol was designed for analysis.

Results: Patients were reviewed at five years two months on average. There were two complications: fusion of the intentional ulnar pseudarthrosis and one pseudarthrosis of the distal radioulnar joint. Time to resumption of former activity was nine months on average. Two patients could not resume their former activity. Seven patients complained of mechanical pain at the ulnar resection. Three patients reported cracking sounds along the ulnar border of the wrist and two patients presented an objective snap during pronosupination. Clinically, the ulnar stump was unstable in the sagittal plan in all cases. Radiographs confirmed this instability. Clinically, there was also an instability in the frontal plane in three patients. The dynamic films did not confirm frontal instability.

Discussion: Although less so than after the Darrach procedure, the proximal ulnar stump is the principle complication of the Savué-Kapandji procedure. Preservation of the structures stabilising the distal ulnar stump is crucial: periosteum, interosseous membrane, ulnar extensor of the carpus, pronator quadratus. Our use of a shorter resection made as distally as possible was only able to avoid a certain degree of instability which was nevertheless well tolerated.

Conclusion: The Sauvé-Kapandji procedure provides very satisfactory results for pain and motion. All patients appeared to have some degree of distal ulnar stump instability which was as a rule well tolerated. Nevertheless, one patient required a revision for stabilisation. This instability remains an unsolved problem which apparently cannot be prevented even with a very rigorous technique.

Purpose: The pisitriquetral articulation can be a source of pain, particularly after trauma. If conservative treatment fails, pisiformectomy appears to be the best alternative. The purpose of this work was to assess clinical and functional outcome after pisiformectomy.

Material and method: Thirteen patients were reviewed 31.5 months (mean) after pisiformectomy. Two patients had a bilateral procedure giving 15 pisiformectomies. Occupation-related trauma was the principal cause. Four patients also had ulnar neuropathy. The same operative technique was used for all patients and a visual analogue scale was used to assess pain.

Results: There were no postoperative complications. At last follow-up, outcome was excellent in twelve cases, good in two and fair in one (n=15). Residual pain was scored a mean 0.8 points versus 6.4 points preoperatively (p< 0.001). Wrist motion was improved after surgery.

Conclusion: There are many causes of pisotriquetral disease, but trauma, or microtraum, predominates. Pisiformectomy is the best treatment after failure or deterioration of results of conservative treatment. It must be remembered however that pisotriquetral disease may be a revealing sign of a regional disorder that must be identified.

We describe an operation to relieve compression of the lateral antebrachial cutaneous nerve at the elbow. Between 1987 and 1997 we operated on seven patients, one with bilateral compression. In two the compression was associated with injury to biceps. A longitudinal or a transverse incision was carried out and the nerve was released from the deep fascia. Partial excision of the biceps aponeurosis was undertaken in the patients who did not have injury to biceps; some additional procedures were required for those patients with injuries. All patients had symptomatic relief.