Aims

Periprosthetic fractures (PPFs) following hip arthroplasty are complex injuries. This study evaluates patient demographic characteristics, management, outcomes, and risk factors associated with PPF subtypes over a decade.

Aims. The aim of this study was to compare the functional and radiological outcomes in patients with a displaced fracture of the hip who were treated with a cemented or a cementless femoral stem. Patients and Methods. A four-year follow-up of a randomized controlled study included 141 patients who underwent surgery for a displaced femoral neck fracture. Patients were randomized to receive either a cemented (n = 67) or a cementless (n = 74) stem at hemiarthroplasty (HA; n = 83) or total hip arthroplasty (THA; n = 58). Results. Early differences in functional outcome, assessed using the Harris Hip Score, the Short Musculoskeletal Functional Assessment score and EuroQol-5D, with better results in cemented group, deteriorated over time and there were no statistically significant differences at 48 months. Two (3%) patients in the cemented group and five (6.8%) in the cementless group underwent further surgery for a periprosthetic fracture. This difference was statistically significant (p = 0.4). No patient underwent further surgery for instability or infection between one and four years postoperatively. The mortality and the radiological outcomes were similar in both groups. Conclusion. Patients with a displaced femoral neck fracture treated with an arthroplasty using a cemented or cementless stem had good function and few complications up to four years postoperatively. However, due to the poor short-term functional outcomes in the cementless group, the findings do not support their routine use in the treatment of these elderly patients. Cite this article: Bone Joint J 2018;100-B:1087–93

Total hip replacements have been shown to give superior outcomes in patients with intracapsular fractures of the neck of femur compared with hemiarthroplasty. Collarless uncemented femoral stems give excellent long term results in elective hip replacements but there are few studies looking at their outcomes in fractured neck of femur patients. There is some concern that in trauma patients bone quality maybe inferior as most neck of femur fractures are secondary to osteoporosis. The presence of osteoporosis and subsequent widened femoral canal may compromise the mechanical stability of uncemented femoral stems and result in early subsidence, which can lead to altered leg length and decreased hip stability. The aim of this study was to assess whether early subsidence occurred when collarless uncemented stems were used to treat patients with fractures of the neck of femur. Post-operative radiographs of 33 patients, mean age 71, who underwent an uncemented collarless total hip replacement for a fracture, were reviewed. The distance from the calcar to the tip of the prosthesis was measured for each patient on the initial post operative radiograph and again on the follow-up radiograph at 6 months post operation. Any subsidence was recorded and magnification for each radiograph was calculated by measuring the diameter of the femoral head, which was known to be 36mm. Distances were then adjusted for magnification. The same procedure was performed on 36 age-matched patients, mean age 71, who underwent elective uncemented total hip replacements for osteoarthritis. Hospital notes for each patient were reviewed to assess for complications and DEXA scan results for trauma patients were also evaluated where available. The mean femoral stem subsidence was significantly greater in the fracture cohort than in elective patients (p = 0.001) with mean subsidence of 4.07mm (range 0.02–18.5mm) and 1.57mm (range 0–5.5mm) respectively. In the fracture cohort there were 3 revisions within 6 months of surgery, 1 for infection and 2 for femoral stem subsidence leading to dislocation. There were no revisions in the elective cohort. DEXA scan results were available for 21 of the 33 fracture cohort patients. All these patients had abnormal bone density with 52% being osteoporotic and 48% osteopenic. This study showed that collarless uncemented stems subsided significantly when performed for fractures and had a high early revision rate. We therefore recommend that cemented or collared femoral stems be used in patients with femoral neck fractures requiring total hip replacement to reduce the risk of femoral stem subsidence

Introduction. Modern cementless press fit stems rely on early fixation and stability for osteointegration and longterm success with early migration increasing the risk of failure. The Ein Bild Roentegen Analyse Femoral Component Analysis (EBRA-FCA) methods allow accurate measurement of femoral stem subsidence without the need for Tantalum markers. The degree of subsidence of femoral stems in the first two years has been shown to be highly predictive of failure when using the cut off value of 1.5 mm. We aimed to measure the early migration pattern of a titanium alloy, tapered, plasma and hydroxyapatite coated femoral stem and any factors associated with subsidence. Methods. Between January 2005-June 2007, 387 Accolade cementless femoral stems (Stryker, Allendale NJ) were implanted at our institution. Seventy-seven had a minimum of two years post operative follow up and a complete set of pre and postoperative radiographs for analysis. Our group inlcuded 45 females with a mean age of 71.4 years, and 32 males with a mean age of 68.5 years. The primary diagnosis was degenerative osteoarthritis in 71 patients, avascular necrosis in two, and post fracture in four patients. The average BMI was 27.1. We measured the canal index to assess bone quality and the canal calcar index to assess the proximal femoral morphology. Immediate postoperative radiographs were assessed for canal fill of the prosthesis and implantation varus/valgus angles. The EBRA-FCA software was used to obtain migration curves for each stem. Results. The mean follow up was 29.3months (24–48). The mean canal index was 0.55 (0.36–0.68) with a mean canal calcar index of 0.54 (0.39–0.79). The average canal fill index at the midpoint of the stem was <0.8 in 37 stems and >80 in 40 stems. The average subsidence at 24 months was 2 mm and this had risen to 2.4 mm by 36 months postoperatively. When analysed using a Kaplan Meier curve using 1.5 mm as an end point we found a survivorship of 63.4% (52.3–74.5) at 24 months and this had worsened to 41.6% (26.6–56.5) by 36 months. Multivariate and univariate regression analysis of measured variables did not reveal any significant hazard for any factor other than the larger stem sizes doing worse. Discussion. Although several cementless tapered stem designs have had an excellent track record, our migration analysis of the Accolade stem is somewhat concerning. Thirty three percent of stems had reached the 1.5 mm subsidence point by two years. This is of concern as work has previously shown this to predict failure of stems with aseptic loosening at ten years with an accuracy of 79%. If these stems go on to fail at the predicted rate this would represent an unacceptably high level of failure. Our data raises serious concerns about the overall clinical performance of this stem design due to poor initial stability and integration

Aims

Periprosthetic femoral fractures (PFF) following total hip arthroplasty (THA) are devastating complications that are associated with functional limitations and increased overall mortality. Although cementless implants have been associated with an increased risk of PFF, the precise contribution of implant geometry and design on the risk of both intra-operative and post-operative PFF remains poorly investigated. A systematic review was performed to aggregate all of the PFF literature with specific attention to the femoral implant used.

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.

Cite this article: Bone Joint J 2015;97-B:94–9.