Bone stock loss secondary to debris and mechanic alin-stability presents a challenge in revision hip arthroplasty. The aim of our study is to evaluate the clinical outcome of revision hip arthroplasty using the Oxford hip prosthesis combined with impaction allografting.

Between 1999 and 2002, we revised 72 hips in 69 patients using this technique (mean age 65years). Indications were aseptic loosening (56), infection (8), peri-prosthetic fracture (7) and a broken stem (1). The mean time to revision was 8.5 years (1–21years). Patients were assessed clinically and with the Oxford Hip Score (OHS) pre- and post-operatively. Fifty-seven patients also had acetabular revision. Four patients required femoral osteotomy to remove the old prosthesis. We used a mean of 1.8 (1–4) femoral heads per operation.

Patients were mobilised partially weight bearing (8weeks) followed by a gradual return to full loading. Complications included peri-operative femoral fracture (6), infection (6), dislocation (10), DVT (1)and PE (2). The average blood transfusion was 1.8 units (0–9). The OHS improved from 45 (26–58) pre-operatively to 24.3 post-operatively (12–43). No hip has been re-revised for aseptic loosening at a mean follow-up of 32.7months (16–51).

The Oxford hip is a trimodular prosthesis with a polished tapered metaphyseal section that is free to slide and rotate on the stem. The stem is first inserted uncemented into the diaphysis. Bone graft is impacted proximally, with mesh if necessary, and then the proximal wedge is cemented in. The wedge allows for some subsidence in the cement and creates optimal radial force transmission, which is essential for bone-remodelling stimulation and preventing proximal stress shielding. Although this is a short-term experience, we believe that the use of the tri-modular Oxford stem combined with minimal proximal impaction allografting is a reliable method of dealing with difficult revision femoral surgery. The results were comparable with a primary arthroplasty in terms of pain relief and functional results.

Purpose of the study Function is strongly infl uenced by proprioceptive ability, this prospective longitudinal study aimed to evaluate the change in proprioceptive performance after knee replacement; comparing total to unicompartment replacement.

Methods and Results Two groups of patients with OA as diagnosed clinically and by X-ray were recruited. Group 1 consisted of 15 patients (mean age 65.8yrs range 57-72yrs, 10 females & 5 males) listed for Total Knee Arthroplasty (TKA) with the AGC (Biomet, UK). Group 2 consisted of 19 patients (mean age 65.5yrs range 52–75yrs; 9 females & 10 males) listed for Oxford Uni-compartmental Knee Arthroplasty (OUKA) for medial compartment OA. The ACL and PCL were present and preserved in all patients in Group 2, while only the PCL was preserved for Group 1 patients.

Joint Position Sense (JPS) & sway were used as measures of proprioception performance. Both groups were assessed pre- and 6 months post-op. JPS was measured using an isokinetic dynamometer (KinCom, Chatanooga Ltd) as the error in actively and passively reproducing fi ve randomly ordered knee fl exion angles (30°, 40°, 50°, 60° and 70°). Sway (area, path and velocity) was measured during single leg stance using a Balance Performance Monitor (SMS Medical) for 30-second interval. Functional outcome was assessed using the Oxford Knee Score (OKS).

Pre-operatively, no differences in JPS or sway were found between limbs in either group. No differences existed between the two groups.

Post-operatively, both groups had signifi cant improvement of JPS in the operated limb only (Mean ± standard deviation for UKA 4.64±1.44° and for TKA 5.18±1.35°). No changes in JPS were seen in the control side. Group 2 patients showed signifi cant improvement in both sway area and path (p< .0001) for both limbs post-operatively. No signifi cant post-operative changes in sway occurred in either limb of Group 1 patients.

The OKS improved post-operatively in both groups, rising from 21.4 to 35.5 for Group 1 patients and from 23.9 to 38 for Group 2 patients.

Conclusion Interestingly, joint position sense improved for both groups but did not seem to show any difference between UKA and TKA. Postural sway was infl uenced by joint replacement type. Ligament retention may contribute to improved global postural control seen after unicompartmental knee arthroplasty and may explain the higher level of function seen in these patients.

Aim: To investigate the functional and radiological outcome of shelf acetabuloplasty in adults with significantly symptomatic acetabular dysplasia, with a minimum of a 5 year follow-up.

Material and Methods: 77 consecutive shelf procedures (68 patients) with an average follow-up of 10.9 years (range: 6–17) were reviewed. The Oxford hip score (OHS) was used for clinical assessment. Centre-edge angle (CEA) and acetabular angle (AA) were measured as indicators of joint containment. The severity of osteoarthiritis was based primarily on the extent of joint space narrowing. Survivorship analyses using conversion to THR as an endpoint were performed. Logrank tests were used to compare the survivorship of the shelf procedure against the variables of age, preoperative osteoarthiritis, pre and postoperative AA, CEA angles.

Results: The average age at time of surgery was 33 years (range: 17–60). At the time of the last follow-up, the mean OHS was 34.6 (maximum score: 48). Mean postoperative CEA was 55 (Pre-operatively: 13 degrees) while mean postoperative AA was 31 (Pre-operatively: 48 degrees). Thirty percent of hips needed THR at an average duration of 7.3 years. The survival in the 45 patients with only slight or no joint space narrowing was 97% (CI, 93%-100%) at 5 years and 75% (CI, 51%-100%) at 10 years. This was significantly higher (p≤= 0.0007) than the survival in the 32 patients with moderate or severe osteoarthiritis, which was 76% (CI, 55%-89%) at 5 years and 22% (CI, 5%-38%) at 10 years. There was no significant relationship between survival and age, pre and postoperative AA, CEA angles (p> 0.05).

Conclusion: Shelf-acetabuloplasty offers symptomatic relief to adults with acetabular dysplasia but overall deteriorates with time. About 50% of the patients do not need THR for over 10 years. Best results with shelf-acetabuloplasty were achieved in patients with slight or no joint narrowing.

Purpose of the study: To evaluate the clinical outcome of revision total hip arthroplasty (THA) using the Oxford Hip prosthesis combined with impaction allografting. Methods and results: The Oxford hip is a trimodular prosthesis with a polished tapered metaphyseal section that is free to slide on the stem. The stem is inserted uncemented into the diaphysis, bone graft is impacted proximally, with mesh if necessary, and then the proximal wedge is cemented in.

Between 1999 and 2002, we revised 72 hips in 69 patients using this technique (mean age 65years, 28 to 88). Fifty-six cases had aseptic loosening, 8 had infection (2 stages), 7 had peri-prosthetic fractures and 1 had a broken stem. The mean time to revision was 8.5years (1 to 21). Patients were assessed clinically and with the Oxford Hip Score (OHS) pre- and post-operatively. Fifty-seven patients also had acetabular revision. Four patients required femoral osteotomy to remove the old prosthesis. We used a mean of 1.8 (1 to 4) femoral heads per operation.

Complications included 6 peri-operative femoral fractures diagnosed at operation and fixed successfully, 6 infections, 10 dislocations (2 were recurrent), one deep vein thrombosis, 2 pulmonary embolism and one gastrointestinal haemorrhage. The average blood transfusion was 1.8 units (0 to 9).

The OHS improved from 45 (26 to 58) pre-operatively to 24.3 post-operatively (12 to 43). No hip has been re-revised for aseptic loosening at a mean follow-up of 32.7 months (16 to 51).

Conclusion: Although we accept that this is only a preliminary experience, we believe that the use of the trimodular Oxford stem combined with minimal proximal impaction allografting was found to be a reliable method and a successful way of dealing with revision femoral surgery. The results were comparable with a primary arthroplasty in terms of pain relief and functional results