Aims

Acetabular retroversion is a recognized cause of hip impingement and can be influenced by pelvic tilt (PT), which changes in different functional positions. Positional changes in PT have not previously been studied in patients with acetabular retroversion.

Aims

Periacetabular osteotomy (PAO) is an established treatment for acetabular dysplasia. It has also been proposed as a treatment for patients with acetabular retroversion. By reviewing a large cohort, we aimed to test whether outcome is equivalent for both types of morphology and identify factors that influenced outcome.

Aims

Periacetabular osteotomy is an effective way of treating symptomatic hip dysplasia. We describe a new minimally invasive technique using a modification of the Smith-Peterson approach.

We performed a prospective, longitudinal cohort study to assess for any compromise in acetabular correction when using this approach, and to see if the procedure would have a higher complication rate than that quoted in the literature for other approaches. We also assessed for any improvement in functional outcome.

Stress fractures occurring in the pubis and ischium after peri-acetabular osteotomy (PAO) are not well recognised, with a reported incidence of 2% to 3%. The purpose of this study was to analyse the incidence of stress fracture after Bernese PAO under the care of two high-volume surgeons. The study included 359 patients (48 men, 311 women) operated on at a mean age of 31.1 years (15 to 56), with a mean follow-up of 26 months (6 to 64). Complete follow-up radiographs were available for 348 patients, 64 of whom (18.4%) developed a stress fracture of the inferior pubic ramus, which was noted at a mean of 9.1 weeks (5 to 55) after surgery. Most (58; 91%) healed. In 40 of the patients with a stress fracture (62.5%), pubic nonunion also occurred. Those with a stress fracture were significantly older (mean 33.9 years (16 to 50) vs 30.5 years (15 to 56), p = 0.002) and had significantly more mean pre-operative deformity: mean centre–edge angle (9.8° (-9.5 to 35) vs 12.4° (-33 to 28), p = 0.04) and mean Tönnis angle (22.8° (0 to 45) vs 18.7° (-2 to 38), p < 0.001). The pubic nonunion rate was significantly higher in those with a stress fracture (62.5% vs 7%, p < 0.001), with regression analysis revealing that these patients had 11.8 times higher risk than those without nonunion.

Cite this article: Bone Joint J 2015; 97-B:24–8.

The inherent challenges of total hip replacement (THR) in children include the choice of implant for the often atypical anatomical morphology, its fixation to an immature growing skeleton and the bearing surface employed to achieve a successful long-term result. We report the medium-term results of 52 consecutive uncemented THRs undertaken in 35 paediatric patients with juvenile idiopathic arthritis. The mean age at the time of surgery was 14.4 years (10 to 16). The median follow-up was 10.5 years (6 to 15). During the study period 13 THRs underwent revision surgery. With revision as an endpoint, subgroup analysis revealed 100% survival of the 23 ceramic-on-ceramic THRs and 55% (16 of 29) of the metal- or ceramic-on-polyethylene. This resulted in 94% (95% CI 77.8 to 98.4) survivorship of the femoral component and 62% (95% CI 41.0 to 78.0) of the acetabular component. Revision of the acetabular component for wear and osteolysis were the most common reasons for failure accounting for 11 of the 13 revisions.

The success seen in patients with a ceramic-on-ceramic articulation seems to indicate that this implant strategy has the potential to make a major difference to the long-term outcome in this difficult group of patients.

Ceramic-on-ceramic bearings in hip replacement have low rates of wear and are increasingly being used in young adults. Our aim was to determine the incidence of audible phenomena or other bearing-related complications.

We retrospectively analysed 250 ceramic-on-ceramic hip replacements in 224 patients which had been implanted between April 2000 and December 2007. The mean age of the patients at operation was 44 years (14 to 83) and all the operations were performed using the same surgical technique at a single centre.

At a mean follow-up of 59 months (24 to 94), the mean Oxford hip score was 40.89 (11 to 48). There were six revisions, three of which were for impingement-related complications. No patient reported squeaking, but six described grinding or clicking, which was usually associated with deep flexion. No radiological evidence of osteolysis or migration of the components was observed in any hip.

The early to mid-term results of contemporary ceramic-on-ceramic hip replacement show promising results with few concerns in terms of noise and squeaking. Positioning of the acetabular component remains critical in regard to the reduction of other impingement-related complications.

Introduction: We present the results of a prospective study of the blood transfusion requirements in patients undergoing a Bernese periacetabular osteotomy (PAO) with the use of an intra-operative cell-saver and without pre-donated blood. These data were compared with an earlier audit of patients who underwent this procedure without use of a cell saver.

Material and Methods: A cohort of 50 patients (56 hips) underwent a PAO for hip dysplasia between December 2006 and November 2008 performed by the senior author. The average age was 29 years (17–51) and there were 38 females and 12 males. The average weight was 69.96 kg (46–110) and the mean duration of operation was 136 minutes (100–240). A cell saver (Fresenius-Hemocare, Germany) was used intra-operatively for this cohort. Pre-operative Hb, post-operative Hb taken the day after surgery and any units transfused were documented. A post-operative transfusion policy was adopted where a haemoglobin (Hb) concentration of < 7.5 g/dl was an indication for transfusion or where a patient was sufficiently symptomatic

Results: The mean pre-operative Hb was 13.60 g/dl (10.8–15.9) and the mean post-operative Hb was 9.91 g/dl (6.4–11.8). Overall 4 patients received post-operative allogenic blood transfusion; 3 patients receiving one unit and one patient receiving 2 units. No patients received intra-operative allogenic blood.

Conclusion: Compared to our previous audit, the use of the cell saver resulted in an improvement in the mean post-operative Hb, (9.2 g/dl compared to 8.0 g/dl). The transfusion rate was also reduced (7.27% compared to 10.8%)..

Assessing femoral head coverage is a crucial element in acetabular surgery for hip dysplasia. Plain radiographic indices give rather limited information. We present a novel CT-based method that measures the fraction of the femoral head that is covered by the acetabulum. This method also produces a direct image of the femoral head with the covered part clearly represented, and it also measures acetabular inclination and anteversion. We used this method to determine normal coverage, and applied it to a prospective study of patients with hip dysplasia undergoing periacetabular osteotomy.

Twenty-five normal and 26 dysplastic hips were studied. On each CT scan points were assigned on the femoral head surface and the superior half of the acetabular rim. The anterior pelvic plane was then defined, and the pelvis was aligned in that plane. Using our custom software programme, the fraction of the head that was covered was measured, in addition to acetabular inclination and anteversion.

In the normal hips femoral head coverage averaged 73% (SD 4). In the same group, mean anteversion was 15.7° (SD 7°), whereas mean inclination was 44.4° (SD 4°). In the dysplastic group femoral head coverage averaged 50.3% (SD 6), whereas mean anteversion and inclination were 18.7° (SD 9°) and 53.2° (SD 5°) respectively.

This is the first study to our knowledge that has used a reliable measurement technique of femoral head coverage by the acetabulum in the normal hip. When this is applied to assessing coverage in surgery for hip dysplasia it allows a clearer understanding of where the corrected hip stands in relation to a normal hip. This would then allow for better determination of the likely outcome of this type of surgery. We are presently conducting a prospective study using this technique to study dysplastic hips pre- and post-periacetabular osteotomy.

Introduction: We report the results of activity and functional outcome of matched pair analysis comparing hip resurfacing with total hip replacement with a minimum follow up of 22 months

Materials and Methods: 14 matched pairs were selected in terms of age (within 4 years), sex and diagnosis, of which 10 pairs were females and 4 pairs were males The mean age was 49.7(19 – 63). The Birmingham hip resurfacing was used in all patients in the resurfacing group and the Furlong HAC stem in all cases in the THR group with the CSF cup in most cases. The mean follow up in BHR group was 5.2 years (1.7 – 9.2) and 2.4 years (1.8 – 3.6) in THR group. Functional outcome was measured using Harris Hip score, WOMAC, SF 36 and the UCLA and Tegner activity scores

Results: The mean Harris Hip score, SF 36, WOMAC, UCLA and Tegner activity scores in the BHR group were 86.8, 77.3,49.7, 6.1 and 3.6 respectively. In the Furlong group the Harris Hip score, SF36, WOMAC, UCLA and Tegner activity scores were 82.9, 79.0,29.5, 5.6 and 3.2 respectively. There was no statistical difference in the mean scores between the two groups.

With regard to functional activity, 21% of patients in both the groups scored 8 or more on the UCLA activity scale. 21% of patients in the BHR and 14% in the Furlong group scored 3 or more on the Tegner activity scale

Conclusion: In our study, hip resurfacing was not associated with a significant increase in activity level or functional outcome compared with total hip replacement.

Introduction: Assessing coverage of the femoral head is a crucial element in acetabular surgery for hip dysplasia. Radiographic indices give rather limited information. We present a novel ct-based method that gives an image of the head with the covered area precisely represented. We used this method to measure femoral head coverage in a series of normal hips and in a prospective study of patients with hip dysplasia undergoing peri-acetabular osteotomy.

Methods: Thirteen normal and ten dysplastic hips were studied. On each CT scan anatomical landmarks were assigned on the 3d reconstructed image and used to define the frame of reference. Points were assigned on the femoral head surface and the superior half of the acetabular rim after aligning the pelvis in the anterior pelvic plane. An image was produced representing the femoral head and its covered part. The fraction of the head that was covered was calculated.

Results: The average femoral head coverage in the normal hips was 73.9% (sd 3.2). The average coverage in the dysplastic group was 50.7% (sd 7.9) and after undergoing peri-acetabular osteotomy the average was 67% (sd 6.2).

Conclusion: This is the first study to our knowledge that has used a reliable measurement technique to give an indication of the percent coverage of the femoral head by the acetabulum in the “normal hip”. When this is applied to assessing coverage in surgery to address hip dysplasia it gives a clearer understanding of where the corrected hip stands in relation to a normal hip, and this should allow for better determination of the likely outcome of this type of surgery.

Massive endoprostheses using a cemented intramedullary stem are widely used to allow early resumption of activity after surgery for tumours. The survival of the prosthesis varies with the anatomical site, the type of prosthesis and the mode of fixation. Revision surgery is required in many cases because of aseptic loosening. Insertion of a second cemented endoprosthesis may be difficult because of the poor quality of the remaining bone, and loosening recurs quickly.

We describe a series of 14 patients with triplate fixation in difficult revision or joint-sparing tumour surgery with a minimum follow-up of four years. The triplate design incorporated well within a remodelled cortex to achieve osseomechanical integration with all patients regaining their original level of function within five months.

Our preliminary results suggest that this technique may provide an easy, biomechanically friendly alternative to insertion of a further device with an intramedullary stem, which has a shorter lifespan in revision or joint-sparing tumour surgery. A short segment of bone remaining after resection of a tumour will not accept an intramedullary stem, but may be soundly fixed using this method.

A prospective study on total knee replacement in patients with Juvenile Idiopathic Arthritis was carried out. There were 31 knee replacements in 17 patients; 12 were female. Bilateral procedures were performed in 11 patients; 10 staged during a single admission and 1 performed in a single procedure. The mean age was 19 years (range, 14–26), and the mean follow-up was 23 months (range, 6–44). The surgery was complicated in 9 cases by a previous distal femoral osteotomy. The results were assessed using the Hospital for Special Surgery (HSS) scoring system. A cruciate sacrificing implant was used in all cases, and the patella was resurfaced in 25/31.

The pre-operative mean arc of motion was 62° (range 10°–90° ) and this averaged 89° (range, 20° –115°) at latest follow-up. The pre-operative mean fixed flexion 17° (range, 0° –15° ). The mean pre-operative HSS score was 36 (range, 8–59), and the mean at latest follow-up was 81 (range, 67–95). There has been no sign of aseptic loosening on serial radiographs over the follow-up period. One patient developed a deep infection at 20 months requiring a 2-stage revision and one patient developed a perforated duodenal ulcer postoperatively.

The clinical results are very satisfactory, allowing patients to regain their mobility and independence. The early radiographic results are very encouraging despite the poor bone quality and severe deformities that require correction.

We report the results of a prospective study of 23 patients in which interstitial laser photocoagulation (ILP) was used to treat an osteoid osteoma. ILP is a technique in which tumour tissue is destroyed by direct heating using low-power laser light energy delivered by thin (400 μm) optical fibres which are introduced percutaneously into the tumour under image guidance.

Pain was evaluated before operation and at the latest follow-up using a visual analogue scale with 0 denoting no pain and 10 the worst pain imaginable. The mean follow-up was for 15 months.

The results showed that the mean pain score decreased from 7.5 before operation to 0.95 at the latest follow-up. Fourteen patients had no pain and eight had minor discomfort, not requiring analgesia. One patient required a second procedure because placement of the fibre had not been accurate enough and one developed recurrent symptoms eight months after treatment. All patients were satisfied with the operation because of the rapid resolution of pain, the minimally invasive nature of the procedure, and the fact that there was no postoperative restriction of activity.

We dissected 21 cadaver elbows to determine the relationship of the posterior interosseous nerve to the posterolateral approach to the elbow and head of the radius. At the distal end of the exposure the first branches at risk, those to extensor carpi ulnaris, were on average 6.0 ± 1.0 cm (4.0 to 8.4) from the articular surface of the radial head.

When using the posterolateral approach it is important that the interval between extensor carpi ulnaris and anconeus is clearly identified with the forearm fully pronated. The supinator should be released close to its ulnar border. It is safe to expose the proximal radius as far as the distal aspect of the bicipital tuberosity.