Abstract

During revision THR, the surgery is often difficult and compromised due to lack of patient's bone especially in the pelvis. Any extra bone in the acetabulum is expected to be of advantage to the patient and the surgeon. The aim of this study was to see if preservation of medial acetabular osteophyte in uncemented total hip replacement had any adverse effect on the prosthesis survival or patient satisfaction.

Conventional acetabular preparation involves reaming down to the true floor. This not only medialises the centre of rotation of the hip but also reduces the acetabular offset. In contrast the main surgeon preserved the acetabular offset by preserving some osteophytic bone between the true floor of the acetabulum and the acetabular cup. This is achieved by reaming the acetabular cavity conservatively while achieving secure primary fixation of the prosthesis. We report the outcome of a single surgeon series of such cases. The endpoint was assessed as the need for revision of the acetabular cup.

A total of 106 consecutive patients were identified who underwent uncemented THR from 2005 to 2010. The medial osteophyte was measured on immediate post-operative x-rays, from the “teardrop” to the nearest point of the acetabular cup, by 3 surgeons (one consultant and 2 registrars). The patients were contacted for a telephone interview and their clinical notes, including x-rays, were reviewed.

Outcome was available for 79 patients. 74 patients were available for follow-up and 5 patients died unrelated to THR. Average follow-up was for 8.3 years (range 5.5–10.8). Average age was 62 years. The average medial osteophyte was 1.98 mm (range 0–14mm). One patient had late infection and one had dislocation. There was not a single failure of the acetabular component. The patient satisfaction was high at 8.8 out of 10.

Preservation of medial osteophyte in the acetabulum whilst doing uncemented THR has the advantage of retaining the patient's own bone stock which can be of great advantage to the surgeon as well as the patient should revision THR be required in future. Our study has shown that this can be achieved without compromising the survival of the prosthesis or the patient satisfaction.

This technique may increase the range of motion of the hip by reducing the risk of bony or soft tissue impingement, and also reduce the risk of dislocation. Furthermore, not recreating the native centre of rotation of the hip does not seem to have any adverse effect for the patients, who are very happy with the outcome. We recommend that whilst doing uncemented THR, the acetabulum should not be reamed to the true floor as has been the conventional teaching, but attempt should be made to preserve some medial osteophyte where possible, at the same ensuring that good primary fixation of the cup is achieved. This is to give the patient and surgeon the advantage of extra available bone should revision surgery be required in the future.

Introduction: Rotational forces in ankle injuries can present as isolated lateral malleolus fracture with talar shift or ankle subluxation. It results in medial joint space [clear space] widening, and more than 4 mm is considered significant. The extent of medial soft tissue injury and exploration as a routine is always a debate.

Aim: To see if medial clear space widening correlate with medial soft tissue injury. Also to evaluate the out come of these fracture fixation.

Materials and Methods: Retrospective study on the management of isolated lateral malleolus fractures with significant medial clear space widening. N=40. Patient group A [25] under went only lateral side fixation and in group B [15] had additional medial side soft tissue exploration as a routine based on medial clear space widening.

Fractures were Classified based on the Weber’s system. Pre-operative medial clear space measurement was done by 2 independent observer using PACS measurement tool. Intraoperative details for the method of fixation and the medial soft tissue were analysed.

Most common method of fixation is Neutralisation plate for the lateral side. In Weber B type 1/3 rd of the cases had both plate on the lateral side and syndesmotic screw fixation. 2/3rd of them had only plate fixation.

In Webers C type, only syndesmotic screw in n=3, Plate and screw n=4, only plate in n=9 cases

Radiological measurement of medial clear space average = 9.08mm, range= 5 –22 mm

Conclusion:

Medial clear space does not correlate with any degree of medial soft tissue injury.

Introduction: The anterior and anterolateral approach to the hip traditionally are well described exposures in primary hip arthroplasty with fewer dislocations than the posterior approach. A very debilitating complication associated with the anterolateral approach however is the persistent limp and positive Trendelenburg sign. We discuss our results with respect to abductor function and morphological integrity seen on MRI when using an approach in which we preserve the majority of gluteus medius.

Methods: We carried out a prospective study of thirty-nine consecutive total hip replacements performed through a gluteus medius sparing anterolateral approach. The same hip surgeon performed all these between April and October 2004. Gait analysis and Trendelenburg tests were evaluated during clinical follow-up at six weeks and three months. Coronal STIR and T1 weighted MRI sequences of the abductors were performed between four and six weeks and the findings were agreed by the consensus of two radiologists.

Results: At three-month follow-up all thirty-nine patients tested Trendelenburg negative. Post-operative radiographs showed satisfactory femoral and acetabular component position. MRI findings showed the gluteus medius tendon to be intact with no shortening on T1. Artefacts were found to be less marked in the higher field strength magnet but more apparent in the STIR weighted sequences.

Discussion: We have tried to incorporate the advantages of reduced dislocation rate of the anterolateral approach, whilst avoiding violation of the abductors. The clinical result and radiographic findings we have presented suggest that the described exposure is an effective and safe method of approaching the hip, with minimal disruption of the abductor mechanism. In addition to maintaining the reduced dislocation rate associated with the standard anterolateral approach. Intact abductor function allows for rapid rehabilitation.

The aim of total hip replacement is to relieve pain and restore function in patients with arthritic hips. The majority of standard implants come with a variety of offset sizes based on anthropological data from cadaveric and radiological studies. The placement of these components depend on a number of factors including soft tissue tension and hip stability at the time of hip implantation. The depth of placement of femoral component is solely under the surgeon’s control and can be influenced by the presence or absence of a component collar and the level of the neck resection itself. Inaccuracies in depth of femoral component placement will lead to length inequality which themselves can cause patient dissatisfaction and complications. In order to accurately place the femoral component a sound understanding of proximal femoral geometry is important. An often used landmark in replacement surgery is the tip of greater trochanter which is said to be at the level of the centre of the femoral head. This study is designed to assess the accuracy of this statement in a population of patients presenting for total hip replacement surgery at Nottingham City Hospital.

Pre-operative and post-operative radiographs of the replaced and contralateral hips were obtained and measured. A line perpendicular to the axis of the shaft of the femur touching the tip of the trochanter was used as a reference for depth of placement of measurement. The centre of the femoral head was estimated using concentric circles and marked. The vertical distance between the centre of the femoral head and the reference line was measured; the distance was recorded with reference to the tip of trochanter. Similar measurements were made post-operatively to assess the accuracy of femoral component placement.

Pre-operatively the centre of head was below the tip of trochanter in 85% of patients. The mean distance was 10mmbelow the tip of trochanter, with a range of 6mm above to 24mm below. In only 15% cases was the centre of head at or above the tip of trochanter.

By contrast post-operatively 55% patients had a femoral head centre at or above the level of tip of trochanter. This, therefore, represents a significant degree of lengthening in all patients where the tip of trochanter was used as a reference point for femoral component placement.