United Kingdom National Institute for Health
and Clinical Excellence guidelines recommend the use of total hip replacement
(THR) for displaced intracapsular fractures of the femoral neck
in cognitively intact patients, who were independently mobile prior
to the injury. This study aimed to analyse the risk factors associated
with revision of the implant and mortality following THR, and to
quantify risk. National Joint Registry data recording a THR performed
for acute fracture of the femoral neck between 2003 and 2010 were
analysed. Cox proportional hazards models were used to investigate
the extent to which risk of revision was related to specific covariates.
Multivariable logistic regression was used to analyse factors affecting
peri-operative mortality (<
90 days). A total of 4323 procedures
were studied. There were 80 patients who had undergone revision
surgery at the time of censoring (five-year revision rate 3.25%, 95%
confidence interval 2.44 to 4.07) and 137 patients (3.2%) patients
died within 90 days. After adjusting for patient and surgeon characteristics,
an increased risk of revision was associated with the use of cementless
prostheses compared with cemented (hazard ratio (HR) 1.33, p = 0.021).
Revision was independent of bearing surface and head size. The risk
of mortality within 90 days was significantly increased with higher
American Society of Anesthesiologists (ASA) grade (grade 3: odds
ratio (OR) 4.04, p <
0.001; grade 4/5: OR 20.26, p <
0.001;
both compared with grades 1/2) and older age (≥ 75 years: OR 1.65,
p = 0.025), but reduced over the study period (9% relative risk reduction
per year). THR is a good option in patients aged <
75 years and with
ASA 1/2. Cementation of the femoral component does not adversely
affect peri-operative mortality but improves survival of the implant
in the mid-term when compared with cementless femoral components.
There are no benefits of using head sizes >
28 mm or bearings other
than metal-on-polyethylene. More research is required to determine
the benefits of THR over hemiarthroplasty in older patients and
those with ASA grades >
2.
Endoprosthetic replacement of the proximal femur may be required to treat primary bone tumours or destructive metastases either with impending or established pathological fracture. Modular prostheses are available off the shelf and can be adapted to most reconstructive situations for this purpose. We have assessed the clinical and functional outcome of using the METS (Stanmore Implants Worldwide) modular tumour prosthesis to reconstruct the proximal femur in 100 consecutive patients between 2001 and 2006. We compared the results with the published series for patients managed with modular and custom-made endoprosthetic replacements for the same conditions. There were 52 males and 48 females with a mean age of 56.3 years (16 to 84) and a mean follow-up of 24.6 months (0 to 60). In 65 patients the procedure was undertaken for metastases, in 25 for a primary bone tumour, and in ten for other malignant conditions. A total of 46 patients presented with a pathological fracture, and 19 presented with failed fixation of a previous pathological fracture. The overall patient survival was 63.6% at one year and 23.1% at five years, and was significantly better for patients with a primary bone tumour than for those with metastatic tumour (82.3% vs 53.3%, respectively at one year (p = 0.003)). There were six early dislocations of which five could be treated by closed reduction. No patient needed revision surgery for dislocation. Revision surgery was required by six (6%) patients, five for pain caused by acetabular wear and one for tumour progression. Amputation was needed in four patients for local recurrence or infection. The estimated five-year implant survival with revision as the endpoint was 90.7%. The mean Toronto Extremity Salvage score was 61% (51% to 95%). The implant survival and complications resulting from the use of the modular system were comparable to the published series of both custom-made and other modular proximal femoral implants. We conclude that at intermediate follow-up the modular tumour prosthesis for proximal femur replacement provides versatility, a low incidence of implant-related complications and acceptable function for patients with metastatic tumours, pathological fractures and failed fixation of the proximal femur. It also functions as well as a custom-made endoprosthetic replacement.