The accurate reconstruction of hip anatomy and biomechanics is thought to be important in achieveing good clinical outcomes following total hip arthroplasty (THA). To this end some newer hip designs have introduced further modularity into the design of the femoral component such that neck­shaft angle and anteversion, which can be adjusted intra-operatively. The clinical effect of this increased modularity is unknown. We have investigated the changes in these anatomical parameters following conventional THA with a prosthesis of predetermined neck–shaft angle and assessed the effect of changes in the hip anatomy on clinical outcomes.

In total, 44 patients (mean age 65.3 years (standard deviation (sd) 7); 17 male/27 female; mean body mass index 26.9 (kg/m²) (sd 3.1)) underwent a pre- and post-operative three-dimensional CT scanning of the hip. The pre- and post-operative neck–shaft angle, offset, hip centre of rotation, femoral anteversion, and stem alignment were measured. Additionally, a functional assessment and pain score were evaluated before surgery and at one year post-operatively and related to the post-operative anatomical changes.

The mean pre-operative neck–shaft angle was significantly increased by 2.8° from 128° (sd 6.2; 119° to 147°) to 131° (sd 2.1; 127° to 136°) (p = 0.009). The mean pre-operative anteversion was 24.9° (sd 8; 7.9 to 39.1) and reduced to 7.4° (sd 7.3; -11.6° to 25.9°) post-operatively (p < 0.001). The post-operative changes had no influence on function and pain. Using a standard uncemented femoral component, high pre- and post-operative variability of femoral anteversion and neck–shaft angles was found with a significant decrease of the post-operative anteversion and slight increase of the neck–shaft angles, but without any impact on clinical outcome.

Cite this article: Bone Joint J 2015;97-B:1615–22.

Aims

Femoroacetabular impingement (FAI) has been highlighted and well documented primarily in Western countries and there are few large studies focused on FAI-related morphological assessment in Asian patients. We chose to investigate this subject.

Aims

The aim of this study was to examine the real time in vivo kinematics of the hip in patients with cam-type femoroacetabular impingement (FAI).

We describe our technique and rationale using hybrid fixation for primary total hip arthroplasty (THA) at the Hospital for Special Surgery. Modern uncemented acetabular components have few screw holes, or no holes, polished inner surfaces, improved locking mechanisms, and maximised thickness and shell-liner conformity. Uncemented sockets can be combined with highly cross-linked polyethylene liners, which have demonstrated very low wear and osteolysis rates after ten to 15 years of implantation. The results of cement fixation with a smooth or polished surface finished stem have been excellent, virtually eliminating complications seen with cementless fixation like peri-operative femoral fractures and thigh pain. Although mid-term results of modern cementless stems are encouraging, the long-term data do not show reduced revision rates for cementless stems compared with cemented smooth stems. In this paper we review the conduct of a hybrid THA, with emphasis on pre-operative planning, surgical technique, hypotensive epidural anaesthesia, and intra-operative physiology.

Cite this article: Bone Joint J 2016;98-B(1 Suppl A):54–9.

Aims

We present the clinical and radiological results at a minimum follow-up of five years for patients who have undergone multiple cement-in-cement revisions of their femoral component at revision total hip arthroplasty (THA).

The December 2015 Hip & Pelvis Roundup³⁶⁰ looks at: Vitamin E infusion helpful in polyethylene; Hip replacement in fracture and arthritis; Non-surgical treatment for arthritis; Cost and approach in hip surgery; Who does well in FAI surgery?; AAOS Thromboembolism guidelines; Thromboprophylaxis and periprosthetic joint infection; Fluid collections not limited to metal-on-metal THR

Aims

Treatment guidelines for atypical femoral fractures associated with bisphosphonates have not been established. We conducted a systematic review of the treatment of atypical femoral fractures first, to evaluate the outcomes of surgical fixation of complete atypical fractures and secondly, to assess whether prophylactic surgery is necessary for incomplete atypical fractures.

Aims

Hemiarthroplasty of the hip is usually carried out through either a direct lateral or posterior approach. The aim of this prospective observational study was to determine any differences in patient-reported outcomes between the two surgical approaches.

Objectives

The high revision rates of the DePuy Articular Surface Replacement (ASR) and the DePuy ASR XL (the total hip arthroplasty (THA) version) have led to questions over the viability of metal-on-metal (MoM) hip joints. Some designs of MoM hip joint do, however, have reasonable mid-term performance when implanted in appropriate patients. Investigations into the reasons for implant failure are important to offer help with the choice of implants and direction for future implant designs. One way to assess the performance of explanted hip prostheses is to measure the wear (in terms of material loss) on the joint surfaces.

Aims

The goals of this study were to define the risk factors, characteristics, and chronology of fractures in 5417 revision total hip arthroplasties (THAs).

Aims

To evaluate whether an ultra-low-dose CT protocol can diagnose selected limb fractures as well as conventional CT (C-CT).

Reported rates of dislocation in hip hemiarthroplasty (HA) for the treatment of intra-capsular fractures of the hip, range between 1% and 10%. HA is frequently performed through a direct lateral surgical approach. The aim of this study is to determine the contribution of the anterior capsule to the stability of a cemented HA through a direct lateral approach.

A total of five whole-body cadavers were thawed at room temperature, providing ten hip joints for investigation. A Thompson HA was cemented in place via a direct lateral approach. The cadavers were then positioned supine, both knee joints were disarticulated and a digital torque wrench was attached to the femur using a circular frame with three half pins. The wrench applied an external rotation force with the hip in extension to allow the hip to dislocate anteriorly. Each hip was dislocated twice; once with a capsular repair and once without repairing the capsule. Stratified sampling ensured the order in which this was performed was alternated for the paired hips on each cadaver.

Comparing peak torque force in hips with the capsule repaired and peak torque force in hips without repair of the capsule, revealed a significant difference between the ‘capsule repaired’ (mean 22.96 Nm, standard deviation (sd) 4.61) and the ‘capsule not repaired’ group (mean 5.6 Nm, sd 2.81) (p < 0.001). Capsular repair may help reduce the risk of hip dislocation following HA.

Cite this article: Bone Joint J 2015;97-B:141–4.

Aims

One goal of total hip arthroplasty is to restore normal hip anatomy. The aim of this study was to compare displacement of the centre of rotation (COR) using a standard reaming technique with a technique in which the acetabulum was reamed immediately peripherally and referenced off the rim.

Aims

We present an audit comparing our level I major trauma centre’s data for a cohort of patients with hip fractures in the National Hip Fracture Database (NHFD) with locally held data on these patients.