Aims

Our aim was to determine whether, based on the current literature, bariatric surgery prior to total hip (THA) or total knee arthroplasty (TKA) reduces the complication rates and improves the outcome following arthroplasty in obese patients.

Aims

The optimal management of intracapsular fractures of the femoral neck in independently mobile patients remains open to debate. Successful fixation obviates the limitations of arthroplasty for this group of patients. However, with fixation failure rates as high as 30%, the outcome of revision surgery to salvage total hip arthroplasty (THA) must be considered. We carried out a systematic review to compare the outcomes of salvage THA and primary THA for intracapsular fractures of the femoral neck.

Hip resurfacing procedures have gained increasing popularity for younger, higher demand patients with degenerative hip pathologies. However, with concerns regarding revision rates and possible adverse metal hypersensitivity reactions with metal-on-metal articulations, some authors have questioned the hypothesised superiority of hip resurfacing over total hip arthroplasty. The purpose of this meta-analysis was to compare the clinical and radiological outcomes and complication rates of these two procedures.

A systematic review was undertaken of all published and unpublished research up to January 2010. The primary search was of the databases Medline, CINAHL, AMED and EMBASE, searched via Ovid using MeSH terms and Boolian operators ‘hip’ AND ‘replacement’ OR ‘arthroplasty’ AND ‘resurfacing’. A secondary search of unpublished literature was conducted using the databases SIGLE, the National Technical Information Service, the National Research Register (UK), the British Library's Integrated Catalogue and Current Controlled Trials databases using the same search terms as the primary search. All included studies were critically appraised with the CASP appraisal tool.

In total, 46 studies were identified from 1124 citations. These included 3799 hip resurfacings and 3282 total hip arthroplasties. On meta-analysis, functional outcomes for subjects following hip resurfacing were better than or the same as subjects with a total hip arthroplasty, with significantly higher WOMAC score (Mean Difference (MD)=−2.41; 95% Confidence Interval (CI): −3.88, −0.94; p=0.001), and significantly better Harris Hip Score (range of motion component) (MD=−0.05; 95% CI: (−0.07, −0.03; p<0.0001) and overall Harris Hip Score (MD=2.51; 95% CI: 1.24, 3.77; p=0.0001) in the hip resurfacing compared to total hip arthroplasty cohorts. However, there were significantly greater incidences of heterotopic ossification (Risk Ratio (RR)=1.62; 95% CI: 1.23, 2.14; p=0.006), aseptic loosening (RR=3.07; 95% CI:1.11, 8.50;p=0.03) and revision surgery (RR=1.72; 95% CI: 1.20, 2.45; p=0.003) with hip resurfacing compared to total hip arthroplasty. The evidence-base presented with a number of methodological inadequacies such as the limited use of power calculations and poor or absent blinding of both patients and assessors, potentially giving rise to assessor bias. In respect to these factors, the current evidence-base, whilst substantial in its size, may be questioned in respect to its quality in determining superiority of hip resurfacing over total hip arthroplasty.

We report an independent prospective review of the first 230 Birmingham hip resurfacings in 212 patients at a mean follow-up of five years (4 to 6).

Two patients, one with a loose acetabular component and the other with suspected avascular necrosis of the femoral head, underwent revision. There were two deaths from unrelated causes and one patient was lost to follow-up. The survivorship with the worst-case scenario was 97.8% (95% confidence interval 95.8 to 99.5). The mean Harris hip score improved significantly (paired t-test, p < 0.05) from 62.54 (8 to 92) pre-operatively to 97.7 (61 to 100) at a mean of three years (2.1 to 4.3), then deteriorated slightly to a mean of 95.2 (47 to 100) at a mean of five years. The mean flexion improved from 91.5° (25° to 140°) to 110.4° (80° to 145°) at a mean of three years with no further improvement at five years (111.2°; 70° to 160°).

On radiological review at five years, one patient had a progressive lucent line around the acetabular component and six had progressive lucent lines around the femoral component. A total of 18 femoral components (8%) had migrated into varus and those with lucent lines present migrated a mean of 3.8° (1.02° to 6.54°) more than the rest. Superolateral notching of the femoral neck and reactive sclerosis at the tip of the peg of the femoral component were associated with the presence of lucent lines (chi-squared test, p < 0.05), but not with migration of the femoral component, and are of unknown significance.

Our results with the Birmingham hip resurfacing continue to be satisfactory at a mean follow-up of five years.

Narrowing of the femoral neck after resurfacing arthroplasty of the hip has been described previously in both cemented and uncemented hip resurfacing. The natural history of narrowing of the femoral neck is unknown. We retrospectively measured the diameter of the femoral neck in a series of 163 Birmingham hip resurfacings in 163 patients up to a maximum of six years after operation to determine the extent and progression of narrowing.

There were 105 men and 58 women with a mean age of 52 years (18 to 82). At a mean follow-up of five years, the mean Harris hip score was 94.8 (47 to 100) and the mean flexion of the hip 112.5° (80° to 160°). There was some narrowing of the femoral neck in 77% (125) of the patients reviewed, and in 27.6% (45) the narrowing exceeded 10% of the diameter of the neck. A multiple logistic regression analysis showed a significant association (chi-squared test (derived from logistic regression) p = 0.01) of narrowing with female gender and a valgus femoral neck/shaft angle. There was no significant association between the range of movement, position or size of the component or radiological lucent lines and narrowing of the neck (chi-squared test; p = 0.10 (flexion), p = 0.08 (size of femoral component), p = 0.09 (size of acetabular component), p = 0.71 (femoral component angulation), p = 0.99 (lucent lines)). There was no significant difference between the diameter of the neck at a mean of three years (2.5 to 3.5) and that at five years (4.5 to 5.5), indicating that any change in the diameter of the neck had stabilised by three years (sign rank test, p = 0.60).

We conclude that narrowing of the femoral neck which is found with the Birmingham hip resurfacing arthroplasty is in most cases associated with no adverse clinical or radiological outcome up to a maximum of six years after the initial operation.

Rheumatoid arthritis results in pain and loss of function due to gradual destruction of articular cartilage. The shoulder joint is frequently involved and a prosthetic replacement of the humeral head can restore function and relieve pain. Deficiency of the rotator cuff is common in patients with rheumatoid arthritis. Longevity of movement at the intraprosthetic interface of the bipolar shoulder prosthesis is debatable and has not previously been studied in rheumatoid arthritis.

We report a radiological study of the intraprosthetic movements of a bipolar shoulder replacement in 25 shoulders in 20 patients with rheumatoid arthritis of mean age 66 years (SD 10 years). Shoulders were X-rayed at a minimum of 3 and a maximum of 10 years from surgery. Measurements were repeated in 12 shoulders 3 years later. The patient was positioned in the scapular plane. An initial X-ray was taken with the arm in neutral and a further X-ray taken with the arm in full active abduction. Measurements were taken to determine the movement at the intraprosthetic interface and at the prosthesis/glenoid interface. Interobserver error and intraobserver error were determined using an intraclass correlation coefficient (ICC). A paired T-test and Pearson Correlation Coefficient were used to compare intraprosthetic movement with prosthesis/glenoid movement.

We found that intraprosthetic movement was preserved up to 10 years from surgery. However, there was no significant difference between intraprosthetic movement and shell/glenoid movement, with some shoulders exhibiting paradoxical movement at the intraprosthetic interface. Repeating the measurements after a 3 year interval in a subgroup of 12 shoulders showed a significant difference in intraprosthetic movement. Interobserver and intraobserver reliability for measurements of the movement at the intraprosthetic interface were excellent with a Kappa value of 0.92 for intraobserver error and a Kappa value of 0.94 for interobserver error.

We conclude that movement of the bipolar shoulder prosthesis in rheumatoid shoulders at the intraprosthetic interface is preserved up to 10 years from operation but is not related to or significantly different from prosthesis/glenoid movement and requires further investigation.

Conventional banking of donated femoral heads has been well documented in the literature. It relies on screening potential donors, providing a storage facility and sterilisation techniques which are not standardised. Stored femoral heads have a finite lifetime and wastage does occur. Prion contamination and malignant potential are present with modern storage techniques.

We report a technique of banking the donor’s femoral head in a surgically fashioned subperiosteal pouch, under iliacus. Young patients requiring a total hip replacement who are likely to need revision at a later date are suitable candidates. Patients who have signs of loosening of their total hip replacement and contralateral osteoarthritis are also suitable. The femoral head is retrieved and used for the donor’s own revision surgery. Interim clinical results for 12 patients with the head harvested at a maximum of 5 years from implantation are presented. We report no morbidity at the pouch site and present radiographic results showing good integration of the morselised femoral head bone graft in revision hip surgery. Histological results are also presented.

Autobanking of the patient’s own femoral head has the advantage of providing a graft with a reduced risk of infection, rich in growth factors, with the potential of osteoinduction. It eliminates the need for a storage facility, screening programme and provides a portable storage facility if the patient moves area.