The management of peri-prosthetic fracture following total hip arthroplasty is difficult, requiring expertise in both trauma and revision surgery. With rising numbers of patients in the population living with hip prostheses in situ, their frequency is increasing, and controversy remains over their ideal management. The objective of this study was to review all peri-prosthetic fractures at a single institution to identify injury and treatment patterns, and their associated clinical outcomes. Fifty-four peri-prosthetic fractures in 50 patients were reviewed to determine the relative frequency of fracture types, complication rates, and clinical outcomes. Patient data were obtained through review of the clinical notes and individual patient follow up. Clinical outcomes were evaluated using the Oxford Hip Score (OHS) and Harris Hip Score (HHS). The fractures were classified using the Vancouver system, the majority of which were type B 1 (20) or type B2 (10). The mean time to union for all fracture types was 4.6 months. A high non-union rate was seen amongst fractures fixed operatively. Fifteen percent of fractures went on to develop loosening following treatment, suggesting under-recognition at the time of injury. The average HHS was 73.1 and OHS 30.3 for all fracture types, at a mean follow up of 3.3 years. Of the 15 patients treated with revision surgery, the most common complication was dislocation (27%). Treatment of patients with peri-prosthetic fractures requires recognition of the challenging nature of these injuries, their associated poor prognosis, and high complication rate.
Proximal tibial bone density (BD) is a key determinant in the migration of implants following total knee arthroplasty (TKA). CT-osteodensitometry offers three-dimensional, volumetric analysis of both cortical and cancellous regions and has been shown to be both accurate and reliable about the hip. The primary objective of this study is to assess differences in the bone remodelling pattern (tibial segment) of patients operated on using fixed or rotating platform, using CT-osteodensitometry. The hypothesis is that the presence of a rotating platform optimises stress distribution along the proximal tibia, resulting in reduced proximal bone remodelling of tibia. The secondary objective is to correlate the osteodensitometry and clinical data at follow-up. Following completion of the initial assessment and after obtaining written informed consent, the patients were randomly allocated to either a PFC Sigma fixed bearing or a PFC Sigma rotating platform (mobile bearing) total knee system (DePuy, Leeds, UK). Clinical follow-ups were performed at three months, one year, and two years after the index operation. CT scans were performed immediately post-operatively and at one and two years respectively. 52 knees (47 patients) were randomised for cemented TKR management using rotating or fixed tibia platform and followed up at one and two years. At the two year follow-up, the knee function and patellar scores were comparable in both groups. There were no radiographic signs of loosening, and no revision surgery was performed. Sequential BD measurement from post-operative baseline to two year follow-up showed minimal differences between the fixed and rotating platform implants. Bone density assessment showed a 20% mean loss of cancellous BD and minimal changes of cortical BD, with little differences between the two groups. Loss of cancellous BD appears progressive. In conclusion, this study shows that the mode of fixation of the TKR polyethylene liner does not influence bone remodelling of the proximal tibia after surgery. This is the first study performed to assess separately cortical and cancellous BD changes in THR. There are no data in the literature for comparison.
Avulsion of the distal biceps tendon is an uncommon clinical entity accounting for 3% of all biceps tendon injuries. Various surgical techniques for its repair have been reported, however, the optimal technique is unknown. The two-incision technique is used by three upper limb surgeons at North Shore Hospital. There has been some concern regarding the risk of heterotopic bone formation with this technique. We present a review of a series of patients with distal biceps tendon ruptures treated with the modified two-incision technique to identify and describe any complications that we encountered and also assess the clinical, functional and radiological outcomes of our patients. Over a 4-year period from 2002–2006, 42 distal biceps tendons repairs using the two-incision technique were identified from the hospital database. All 42 patients were males with an average age of 51.9 years. Patients were followed-up prospectively and reviewed at a clinic where they filled out the SF-12 questionnaire and a Mayo Elbow Performance Score was assessed. Clinical assessment was carried out with regards to their range of flexion-extension and their pronation-supination. All peripheral nerves were examined. Isokinetic elbow flexion-extension and forearm pronation-supination were measured and compared to the unaffected extremity. X-rays were taken to identify heterotrophic ossification or proximal radioulnar synostoses. Our review, so far, indicates a good clinical and functional outcome in most of our patients. We identified one patient with heterotrophic bone formation requiring excision. Two patients had a transient lateral ante-brachial cutaneous nerve parasthesia and two patients had re-ruptures following surgery. This study represents a relatively large series of patients. Our results reveal that the two-incision technique is an effective surgical option for the repair of ruptured distal biceps tendons. We found that radioulnar synostoses and heterotrophic ossification are rare following the muscle splitting modification of the two-incision technique.
