Pseudotumours (soft-tissue masses relating to the hip joint) following metal-on-metal hip resurfacing arthroplasty (MoMHRA) have been associated with elevated serum and hip aspirate metal ion levels, suggesting that pseudotumours occur when there is increased wear. This study aimed to quantify the wear of implants revised for pseudotumours and a control group of implants revised for other reasons of failure.

A total of 30 contemporary MoMHRA implants in two groups were investigated: (1) 8 MoMHRA implants revised due to pseudotumour; (2) 22 MoMHRA implants revised due to other reasons of failure. The linear wear of retrieved implants was measured using a Taylor-Hobson Roundness machine. The average linear wear rate was defined as the maximum linear wear depth divided by the duration of the implant in vivo.

In comparison with the non-pseudotumour implant group, the pseudotumour implant group was associated with: (1) significantly higher median linear wear rate of the femoral component: 8.1 um/year (range 2.75-25.4 um/year) vs. 1.97 um/year (range 0.82-13.00 um/year), p=0.002; and (2) significantly higher median linear wear rate of the acetabular component: 7.36 um/year (range 1.61-24.9 um/year) vs. 1.28 um/year (range 0.18-3.33 um/year), p=0.001. Wear on the acetabular cup components in the pseudotumour group always involved the edge, indicating edge-loading of the bearing.

Significantly greater linear wear rates of the MoMHRA implants revised due to pseudotumour support the in vivo elevated metal ion concentrations in patients with pseudotumours. This study is the first to confirm that pseudotumour occurs when there is increased wear at the MoM articulation. Furthermore, edge-loading may be the dominant wear generation mechanism in patients with pseudotumour.

Aim

To delineate which of four common and easily constructed Ilizarov frame configurations is best at resisting shear displacement.

Early methods of treating high-energy tibial plateau fractures by open reduction and internal fixation led to high infection rates and complications. Alternative treatment methods include minimally invasive techniques and implants, external fixator stabilisation (monolateral and circular) and temporary external fixation followed by delayed definitive surgery. A clear understanding of the different fracture types is critical in achieving optimum results with minimally invasive techniques. The Chertsey classification system is based on the direction of force at the time of injury and helps with surgical planning. There are three groups: valgus, varus or axial fracture patterns.

124 tibial plateau fractures have been surgically treated in our hospital since 1995; there were 62 valgus, 14 varus and 48 axial type fracture patterns. Seventy-nine underwent open reduction with internal fixation, and forty-five had an Ilizarov frame. For valgus fractures the average IOWA knee score was 88 if internally fixed or 86 with an Ilizarov frame, range of motion was 140 and 131 degrees and time to union was 81 versus 126 days respectively. Varus fractures had an IOWA score of 83 (ORIF) and 95 (Ilizarov), ROM of 138 and 130 degrees and time to union of 95 versus 82 days. For axial fractures the average IOWA knee score was 85 (ORIF) compared to 82 (Ilizarov), the ROM was 124 degrees for both groups and time to union was 102 days and 141 days respectively.

Deep vein thrombosis occurred in 9% of cases with an Ilizarov and one patient required a total knee replacement for painful post-traumatic osteoarthritis. The infection rate for those internally fixed was 2.5%, three patients required a total knee replacement and 2.5% suffered a DVT.

Our results are comparable to the literature and the Chertsey classification of tibial plateau fractures helps with surgical planning.

Background

The UKITE was started nationally as a yearly, online, curriculum-based, self-assessment examination in 2007 for the orthopaedic trainees. It remains free if trainees contribute questions. The examination has matured, expanded its services and established over 3 years. The UKITE is funded by DePuy.

This prospective longitudinal study compared the results of isolated endoscopic ACL reconstruction utilising 4-strand hamstring tendon (HT) or patellar tendon (PT) autograft over 15-years with respect to reinjury, clinical outcomes and osteoarthritis.

Ninty consecutive patients with isolated ACL rupture were reconstructed with a PT autograft and 90 patients received HT autograft, with an identical surgical technique. Patients were assessed at 2, 5, 7, 10 and 15 years. Assessment included the IKDC Knee Ligament Evaluation, radiographic evaluation, KT1000, Lysholm Knee Score, kneeling pain, and clinical outcomes.

Subjects who received the PT graft had significantly worse outcomes compared to those who received the HT graft at 15 years for the variables of radiologically detectable osteoarthritis (p=0.03), motion loss (p=0.01), single leg hop test (p=0.002), participation in strenuous activity (p=0.05), and kneeling pain (p=0.04). There was no significant difference between the HT and PT groups in overall IKDC grade (p=0.31). ACL graft rupture occurred in 16% of HT group and 8% of the PT group (p=0.07). ACL graft rupture was associated with non-ideal tunnel position (odds ratio 5.0) and males (odds ratio 3.2). Contralateral ACL rupture occurred in significantly more PT patients (24%) than HT patients (12%) (p=0.03), and was associated with age < 18 years (odds ratio 4.1) and the patellar tendon graft (odds ratio 2.6). Radiologically detectable osteoarthritis at 15 years was associated with the PT graft (odds ratio 2.3).

Significant differences have developed in the groups at 15 years after surgery which were not seen at earlier reviews. Compared to the HT Group, the PT group had significantly worse outcomes with respect to radiological osteoarthritis, extension loss and functional tests but no significant difference in laxity was identified. There was a high incidence of ACL injury after reconstruction, to both the reconstructed and the contralateral knee.

Introduction

The management of degenerative arthritis of the knee in the younger, active patient presents a challenge to the orthopaedic surgeon. Surgical treatment options include: high tibial osteotomy (HTO), unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA). The aim of this study was to examine the long-term survival of closing wedge HTO in a large series of patients up to 19 years after surgery.