Periprosthetic femoral fractures are a challenging problem to manage. In the literature various constructs have been designed and tested, most requiring cables for proximal fixation. The Synthes Locking Attachment Plate (LAP) has been designed to achieve proximal fixation without the use of cables. The aim of this study was to biomechanically evaluate the LAP construct in comparison to a Cable plate construct, for the fixation of periprosthetic femoral fractures after cemented total hip arthroplasty (THA). Twelve synthetic femora were tested in axial compression, lateral bending and torsion to determine initial stiffness, and stiffness following fixation of a simulated midshaft fracture with and without a bone gap. Two different fracture fixation constructs (six per group) were assessed. Each construct incorporated a broad curved LCP with bi-cortical locking screws for distal fixation. In the Cable construct, 2 cables and 2 uni-cortical locking screws were used for proximal fixation. In the LAP construct, the cables were replaced by a LAP with 4 bicortical locking screws. Axial, lateral bending and torsional stiffness were assessed using intact specimen values as a baseline. Axial load to failure was also measured. The LAP construct was significantly stiffer than the cable construct under axial load with a bone gap (simulating a comminuted fracture) (p=0.01). There were no significant differences between the two constructs in any of the other modalities tested. Loading to failure resulted in no significant differences between constructs, in either initial stiffness or peak load. In conclusion the LAP construct enables bi-cortical screw fixation around a prosthesis. Compared to cables, this was stiffer when there was a bone gap and thus should offer improved proximal fixation of Vancouver B1 proximal femoral fractures in cemented THA

Aims

Revision total hip arthroplasty in patients with Vancouver type B3 fractures with Paprosky type IIIA, IIIB, and IV femoral defects are difficult to treat. One option for Paprovsky type IIIB and IV defects involves modular cementless, tapered, revision femoral components in conjunction with distal interlocking screws. The aim of this study was to analyze the rate of reoperations and complications and union of the fracture, subsidence of the stem, mortality, and the clinical outcomes in these patients.

Aims

Pelvic discontinuity is a rare but increasingly common complication of total hip arthroplasty (THA). This single-centre study evaluated the performance of custom-made triflange acetabular components in acetabular reconstruction with pelvic discontinuity by determining: 1) revision and overall implant survival rates; 2) discontinuity healing rate; and 3) Harris Hip Score (HHS).

Aims

The risk of mechanical failure of modular revision hip stems is frequently mentioned in the literature, but little is currently known about the actual clinical failure rates of this type of prosthesis. The current retrospective long-term analysis examines the distal and modular failure patterns of the Prevision hip stem from 18 years of clinical use. A design improvement of the modular taper was introduced in 2008, and the data could also be used to compare the original and the current design of the modular connection.

Aims

This study aimed to determine whether lateral femoral wall thickness (LWT) < 20.5 mm was associated with increased revision risk of intertrochanteric fracture (ITF) of the hip following sliding hip screw (SHS) fixation when the medial calcar was intact. Additionally, the study assessed the association between LWT and patient mortality.

Background. Sub-trochanteric fractures are challenging to treat due to various anatomical and biomechanical factors. High tensile forces contribute to the challenge of fracture reduction. Intramedullary nailing has become the treatment of choice. If anatomical reduction is not achieved, any mal-alignment will predispose to implant failure. Open reduction with cerclage wires can add to construct stability and improve the quality of reduction. There is no consensus or classification to guide surgeons on when to perform open reduction, which is often performed intra-operatively when closed reduction fails often with no planning. This can lead to intraoperative delays as theatre staff would not have prepared the correct equipment necessary for open reduction. Objectives. The purpose of this study was to assess outcomes of closed and open reduction of traumatic sub-trochanteric fractures treated with intramedullary nailing and to propose a new classification system to dictate management. Methods. After a review of current classification systems, a 3-tier classification was proposed (Type 1, 2 and 3). Type 1 indicated a transverse fracture, Type 2 was a spiral fracture with an intact posterior and medial wall and a Type 3 fracture were fractures with no posterior and/or medial walls. Over a two-year period (2013–2015), patients with sub trochanteric fractures were classified into Type 1, 2 or 3 injuries based on radiographic appearances by two senior clinicians. Patients with Type 3 injuries were divided into two groups based on whether they were treated with open or closed reduction. A clinical and radiographic review was performed. The primary outcome measure was the incidence of implant failure, whereas secondary outcome measures were related to fracture reduction. Statistical analysis was performed using GraphPad Prism Version 6 (GraphPad Software Inc. California, USA). Fisher's exact test was used for independent categorical data and Mann–U Whitney for continuous nonparametric data. Statistical significance was set at p<0.05. Results. 75 patients had intramedullary nailing for subtrochanteric fractures over the study period with a mean age of 82.6 years. There were 48 patients who had a Type 3 fracture pattern with a deficient medial and/or posterior wall. Reduction was achieved open with cerclage wires in 42% of patients (n=20 and closed in 58% (n=28). Overall there were a total of 18 (37.5%) major complications. In patients treated with closed reduction, 9 patients suffered mechanical complications (6 distal locking screw failures, 3 lag screw cut outs). There was a significantly increased risk of implant failure in patients treated with closed reduction compared to open reduction (p=0.006). No cases with cerclage wire had implant failure. Open reduction with cerclage wires improved the quality of reduction (p=0.0001) compared with closed reduction. There was no significant increase in operating time in patients treated with cerclage wires (p=0.4334). Conclusions. Open reduction with cerclage wires should be considered in patients with Type 3 sub-trochanteric fractures as it has shown to significantly reduce the risk of implant failure and improve the quality of reduction with no significant increase in operating time

Aims

Instability is a common cause of failure after total hip arthroplasty. A novel reverse total hip has been developed, with a femoral cup and acetabular ball, creating enhanced mechanical stability. The purpose of this study was to assess the implant fixation using radiostereometric analysis (RSA), and the clinical safety and efficacy of this novel design.

Aims

Fixation of osteoporotic proximal humerus fractures remains challenging even with state-of-the-art locking plates. Despite the demonstrated biomechanical benefit of screw tip augmentation with bone cement, the clinical findings have remained unclear, potentially as the optimal augmentation combinations are unknown. The aim of this study was to systematically evaluate the biomechanical benefits of the augmentation options in a humeral locking plate using finite element analysis (FEA).

Aims

Custom flange acetabular components (CFACs) are a patient-specific option for addressing large acetabular defects at revision total hip arthroplasty (THA), but patient and implant characteristics that affect survivorship remain unknown. This study aimed to identify patient and design factors related to survivorship.

Objectives

The paradoxical migration of the femoral neck element (FNE) superomedially against gravity, with respect to the intramedullary component of the cephalomedullary device, is a poorly understood phenomenon increasingly seen in the management of pertrochanteric hip fractures with the intramedullary nail. The aim of this study was to investigate the role of bidirectional loading on the medial migration phenomenon, based on unique wear patterns seen on scanning electron microscopy of retrieved implants suggestive of FNE toggling.

Pelvic discontinuity represents a rare but challenging problem for orthopaedic surgeons. It is most commonly encountered during revision total hip replacement, but can also result from an iatrogentic acetabular fracture during hip replacement. The general principles in management of pelvic discontinuity include restoration of the continuity between the ilium and the ischium, typically with some form of plating. Bone grafting is frequently required to restore pelvic bone stock. The acetabular component is then impacted, typically using an uncemented, trabecular metal component. Fixation with multiple supplemental screws is performed. For larger defects, a so-called ‘cup–cage’ reconstruction, or a custom triflange implant may be required. Pre-operative CT scanning can greatly assist in planning and evaluating the remaining bone stock available for bony ingrowth. Generally, good results have been reported for constructs that restore stability to the pelvis and allow some form of biologic ingrowth.

Cite this article: Bone Joint J 2013;95-B, Supple A:109–13.

The use of plate-and-cable constructs to treat periprosthetic fractures around a well-fixed femoral component in total hip replacements has been reported to have high rates of failure. Our aim was to evaluate the results of a surgical treatment algorithm to use these lateral constructs reliably in Vancouver type-B1 and type-C fractures. The joint was dislocated and the stability of the femoral component was meticulously evaluated in 45 type-B1 fractures. This led to the identification of nine (20%) unstable components. The fracture was considered to be suitable for single plate-and-cable fixation by a direct reduction technique if the integrity of the medial cortex could be restored.

Union was achieved in 29 of 30 fractures (97%) at a mean of 6.4 months (3 to 30) in 29 type-B1 and five type-C fractures. Three patients developed an infection and one construct failed.

Using this algorithm plate-and-cable constructs can be used safely, but indirect reduction with minimal soft-tissue damage could lead to shorter times to union and lower rates of complications.

We have managed 27 patients (16 women and 11 men) with a mean age of 68.4 years (50 to 84), with failed total hip replacement and severe proximal femoral bone loss by revision using a distal fix/proximal wrap prosthesis. The mean follow-up was for 55.3 months (25 to 126). The mean number of previous operations was 2.2 (1 to 4). The mean Oxford hip score decreased from 46.2 (38 to 60) to 28.5 (17 to 42) (paired t-test, p < 0.001) and the mean Harris Hip score increased from 30.4 (3 to 57.7) to 71.7 (44 to 99.7) (paired t-test, p < 0.001). There were two dislocations, and in three patients we failed to eradicate previous infection. None required revision of the femoral stem.

This technique allows instant distal fixation while promoting biological integration and restoration of bone stock. In the short term, the functional outcome is encouraging and the complication rates acceptable in this difficult group of patients.

The Kent hip is a distally-locked femoral stem which was developed to address severe proximal bone loss, severe bony deformity and peri-prosthetic fracture.

We reviewed the results of 145 consecutive Kent hips implanted into 141 patients between 1987 and 2000. The indications for implantation were aseptic loosening (75 hips), septic loosening (two), peri-prosthetic and prosthetic fracture (37), severe bony deformity (24), and fracture through a proximal femoral metastasis (seven).

The median time to full weight-bearing after surgery was two days and the mean length of follow-up was 5.1 years (2 to 15). Further revisions were required for 13 femoral stems. With removal of the stem for any reason as an end-point, the cumulative survival at five, ten and 15 years was 93%, 89% and 77%, respectively. In patients aged ≥ 70 years, the cumulative survival at 15 years was 92%, compared with 68% in those aged < 70 years. Because of these findings, we recommend the use of interlocking stems in patients aged ≥ 70 years, particularly in those with a peri-prosthetic fracture, for whom alternative methods are limited. Outcome scores and survival data, compared with other systems, indicate that the Kent hip should be used with caution in younger patients.