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The most common reasons for revision of unicompartmental knee arthroplasty (UKA) are loosening and pain. Cementless components may reduce the revision rate. The aim of this study was to compare the fixation and clinical outcome of cementless and cemented Oxford UKAs. A total of 43 patients were randomised to receive either a cemented or a cementless Oxford UKA and were followed for two years with radiostereometric analysis (RSA), radiographs aligned with the bone-implant interfaces and clinical scores. The femoral components migrated significantly during the first year (mean 0.2 mm) but not during the second. There was no significant difference in the extent of migration between cemented and cementless femoral components in either the first or the second year. In the first year the cementless tibial components subsided significantly more than the cemented components (mean 0.28 mm (sd 0.17) vs. 0.09 mm (sd 0.19 mm)). In the second year, although there was a small amount of subsidence (mean 0.05 mm) there was no significant difference (p = 0.92) between cemented and cementless tibial components. There were no femoral radiolucencies. Tibial radiolucencies were narrow (< 1 mm) and were significantly (p = 0.02) less common with cementless (6 of 21) than cemented (13 of 21) components at two years. There were no complete radiolucencies with cementless components, whereas five of 21 (24%) cemented components had complete radiolucencies. The clinical scores at two years were not significantly different (p = 0.20). As second-year migration is predictive of subsequent loosening, and as radiolucency is suggestive of reduced implant-bone contact, these data suggest that fixation of the cementless components is at least as good as, if not better than, that of cemented devices., (©2015 The British Editorial Society of Bone & Joint Surgery.)

National Institute of Clinical Excellence guidelines state that cemented stems with an Orthopaedic Data Evaluation Panel (ODEP) rating of > 3B should be used for hemiarthroplasty when treating an intracapsular fracture of the femoral neck. These recommendations are based on studies in which most, if not all stems, did not hold such a rating. This case-control study compared the outcome of hemiarthroplasty using a cemented (Exeter) or uncemented (Corail) femoral stem. These are the two prostheses most commonly used in hip arthroplasty in the UK. Data were obtained from two centres; most patients had undergone hemiarthroplasty using a cemented Exeter stem (n = 292/412). Patients were matched for all factors that have been shown to influence mortality after an intracapsular fracture of the neck of the femur. Outcome measures included: complications, re-operations and mortality rates at two, seven, 30 and 365 days post-operatively. Comparable outcomes for the two stems were seen. There were more intra-operative complications in the uncemented group (13% vs 0%), but the cemented group had a greater mortality in the early post-operative period (n = 6). There was no overall difference in the rate of re-operation (5%) or death (365 days: 26%) between the two groups at any time post-operatively. This study therefore supports the use of both cemented and uncemented stems of proven design, with an ODEP rating of 10A, in patients with an intracapsular fracture of the neck of the femur., (©2015 The British Editorial Society of Bone & Joint Surgery.)

Mobile-bearing unicompartmental knee replacements (UKRs) with a flat tibial plateau have not performed well in the lateral compartment, owing to a high dislocation rate. This led to the development of the Domed Lateral Oxford UKR (Domed OUKR) with a biconcave bearing. The aim of this study was to assess the survival and clinical outcomes of the Domed OUKR in a large patient cohort in the medium term. We prospectively evaluated 265 consecutive knees with isolated disease of the lateral compartment and a mean age at surgery of 64 years (32 to 90). At a mean follow-up of four years (sd 2.2, (0.5 to 8.3)) the mean Oxford knee score was 40 out of 48 (sd 7.4). A total of 12 knees (4.5%) [corrected] had re-operations, of which four (1.5%) were for dislocation. All dislocations occurred in the first two years. Two (0.8%) were secondary to significant trauma that resulted in ruptured ligaments, and two (0.8%) were spontaneous. In four patients (1.5%) the UKR was converted to a primary TKR. Survival at eight years, with failure defined as any revision, was 92.1% (95% confidence interval 81.3 to 100). The Domed Lateral OUKR gives good clinical outcomes, low re-operation and revision rates and a low dislocation rate in patients with isolated lateral compartmental disease, in the hands of the designer surgeons.

The National Institute for Health and Clinical Excellence (NICE) guidelines from 2011 recommend the use of cemented hemi-arthroplasty for appropriate patients with an intracapsular hip fracture. In our institution all patients who were admitted with an intracapsular hip fracture and were suitable for a hemi-arthroplasty between April 2010 and July 2012 received an uncemented prosthesis according to our established departmental routine practice. A retrospective analysis of outcome was performed to establish whether the continued use of an uncemented stem was justified. Patient, surgical and outcome data were collected on the National Hip Fracture database. A total of 306 patients received a Cathcart modular head on a Corail uncemented stem as a hemi-arthroplasty. The mean age of the patients was 83.3 years (SD 7.56; 46.6 to 94) and 216 (70.6%) were women. The mortality rate at 30 days was 5.8%. A total of 46.5% of patients returned to their own home by 30 days, which increased to 73.2% by 120 days. The implant used as a hemi-arthroplasty for intracapsular hip fracture provided satisfactory results, with a good rate of return to pre-injury place of residence and an acceptable mortality rate. Surgery should be performed by those who are familiar with the design of the stem and understand what is required for successful implantation.