Aims

Knee osteoarthritis (OA) is characterized by a chronic inflammatory process involving multiple cytokine pathways, leading to articular cartilage degeneration. Intra-articular therapies using pharmaceutical or autologous anti-inflammatory factors offer potential non-surgical treatment options. Autologous protein solution (APS) is one such product that uses the patient’s blood to produce a concentrate of cells and anti-inflammatory cytokines. This study evaluated the effect of a specific APS intra-articular injection (nSTRIDE) on patient-reported outcome measures compared to saline in moderate knee OA.

Trauma and elective orthopaedic demands in New Zealand are increasing. In this study, prospective and retrospective data has been collected at Nelson Hospital and across New Zealand to identify the percentage of elective theatre time lost due to cancellation for acute patient care. Data has been collected from theatre management systems, hospital data systems and logged against secretarial case bookings, to calculate a percentage of elective theatre time lost to acute operating or insufficient bed capacity.

Data was collected over a five-month period at Nelson Hospital, with a total of 215 elective and 226 acute orthopaedic procedures completed. A total of 95 primary hip or knee arthroplasties were completed during this trial while 53 were cancelled. The total number of elective operative sessions (one session is the equivalent of a half day operating theatre time) lost to acute workload was 47.9. Thirty-three percent of allocated elective theatre time was cancelled - an equivalent of approximately one-full day elective operating per week.

Over a five-week period data was collected across all provincial hospitals in New Zealand, with an average of 18% of elective operating time per week lost due to acute workload. Elective cancellations were due to acute operating 40% of the time and bed shortages 60% of the time. The worst effected centre was Palmerston North which had an average of 33% of elective operating cancelled per week to accommodate acute surgery or due to bed shortages.

New Zealand's provincial orthopaedic surgeons are under immense pressure from acute operating that impedes provision of elective surgery. The New Zealand government definition of an ‘acute case’ does not reflect the nature of today's orthopaedic burden. Increasing and aging populations along with staff and infrastructure shortages have financial and societal impacts beyond medicine and require better definitions, further research, and funding from governance.

Constrained implants with intra-medullary fixation are expedient for complex TKA. Constraint is associated with loosening, but can correction of deformity mitigate risk of loosening?

Primary TKA's with a non-linked constrained prosthesis from 2010-2018 were identified. Indications were ligamentous instability or intra-medullary fixation to bypass stress risers. All included fully cemented 30mm stem extensions on tibia and femur. If soft tissue stability was achieved, a posterior stabilized (PS) tibial insert was selected.

Pre and post TKA full length radiographs showed.

77 TKA's in 68 patients, average age 69.3 years (41-89.5) with OA (65%) post-trauma (24.5%) and inflammatory arthropathy (10.5%).

Pre-op radiographs (62 knees) showed varus in 37.0% (HKAA: 4^o-29^o), valgus in 59.6% (HKAA range 8^o-41^o) and 2 knees in neutral.

13 cases deceased within 2 years were excluded. Six with 2 year follow up pending have not been revised. Mean follow-up is 6.1 yrs (2.4-11.9yrs).

Long post-op radiographs showed 34 (57.6%) in central KZ (HKKA 180^o +/- 2^o)^.

Thirteen (22.0%) were in mechanical varus (HKAA 3^o-15^o) and 12 (20.3%) in mechanical valgus: HKAA (171^o-178^o)

Three failed with infection; 2 after ORIF and one with BMI>50. The greatest post op varus suffered peri-prosthetic fracture. There was no aseptic loosening or instability.

Only full-length radiographs accurately measure alignment and very few similar studies exist. No cases failed by loosening or instability, but PPF followed persistent malalignment. Infection complicated prior ORIF and elevated BMI.

This does not endorse indiscriminate use of mechanically constrained knee prostheses. Lower demand patients with complex arthropathy, especially severe deformity, benefit from fully cemented, non-linked constrained prostheses, with intra-medullary fixation. Hinges are not necessarily indicated, and rotational constraint does not lead to loosening.

Aims

The aims of this study were: firstly, to investigate the influence of the thickness of cartilage at the sigmoid notch on the inclination of the distal radioulnar joint (DRUJ), and secondly, to compare the sensitivity and specificity of MRI with plain radiographs for the assessment of the inclination of the articular surface of the DRUJ in the coronal plane.

INTRODUCTION

Multiple sources have consistently reported oxidation indices less than 0.1 with Marathon® inserts implanted up to 10 years. Understanding effects of oxidation level on UHMWPE wear in vivo is of great value. The objective of this study is to characterize the wear performance of Marathon® acetabular inserts at various levels of artificially induced oxidation, quantified using Bulk Oxidation Index (BOI) as determined per ASTM F2102, and to ascertain if wear rate is affected by progressive polyethylene oxidation.

Introduction and Aims: Distal biceps ruptures are an uncommon injury. They represent approximately three percent of all biceps ruptures. Intervention was popularised by Boyd and Anderson who described a two-incision technique. Improved outcome has been achieved with stronger fixation allowing early mobilisation.

Method: All patients who underwent operative fixation of distal biceps ruptures by the senior two authors were identified. All patients were clinically reviewed at a minimum of six months from surgery. Functional outcomes scores in the form of Patient Rated Elbow Evaluation (PREE) and DASH scores were assessed. The operative technique utilised the Endobutton (Smith and Nephew) and is a substantial modification of that published by Bain,G et al.

Results: Thirty-one patients were identified. All patients were male with an average age of 47 years. Average delay to surgery was 24 days. There were no postoperative complications and no repeat ruptures. Thirty patients have returned Patient Rated Elbow Evaluation (PREE) forms with an average score of eight. Cybex testing demonstrates good return of strength when compared to the uninjured side.

Conclusion: Fixation of distal biceps ruptures using this modified Endobutton technique is a safe and effective method.

Introduction and Aims: Unilateral joint destruction in small joints of the hand presents a difficult challenge, particularly in younger patients. Pyrocarbon has a number of properties which may render it more suitable than metal for hemiarthroplasty in selected circumstances. We reviewed the results of our experience with PIP and MCP hemiarthroplasty utilising pyrocarbon implants to evaluate the clinical outcome in each case.

Method: Since December 2001, 10 pyrocarbon hemiarthroplasties were implanted in 10 patients. Eight were implanted into the PIP joint and two into the MCP joint. The average patient age was 34.5 years (range 19–65). Nine procedures were for trauma and one for arthrosis. The decision to implant was taken when other reconstructive options were not considered possible and the patient would otherwise have been offered arthrodesis or amputation or total joint arthroplasty. The patients were reviewed clinically to establish their range of motion, pain control and satisfaction with surgery. Radiographic review was undertaken.

Results: After an average follow-up of 13 months (range three to 23 months) all joints remain in-situ. The average arc of motion is 50.5 degrees. Average extension was minus eight degrees (range 0–20) and average flexion was 58.5 (range 15–90). There was no evidence of loosening. Erosion of the intact side of the joint was noted in only one patient. One patient was not satisfied with the final outcome.

Conclusion: The short-term results of PIP and MCP hemiarthroplasty with a pyrocarbon prosthesis show reasonable promise and this procedure merits further evaluation of its role in the treatment of unilateral joint destruction. It may be preferable to either total joint arthroplasty or fusion, particularly in the younger patient.