Inadequate cementation remains a prime cause of aseptic loosening in Hip Arthroplasties. While good progress has been made in preparation of femoral canal and cement, with newer techniques there are problems with ensuring adequate cement mantle. A distal centraliser available with some prosthesis does aid in better alignment and distal centralisation, but proximal centralisation remains a problem especially with some approaches.

We have recently used a new prosthesis CPS (Endoplus) which has a smooth polished double tapered design and also comes with a proximal and distal centraliser. We undertook a study to evaluate the effect of these on cement mantle, stem alignment, centralisation and supero-medial cement thickness. We defined adequate mantle as a thickness of at least 2mm. 75 consecutive cases were included in the study. All cases were done either by or under direct supervision of the senior author using the antero-lateral approach.

We found 88% of stem’s aligned within 2 deg. of anatomical axis of the femur. Distal tip of the prosthesis was within 2mm of centre of the medullary canal in 92% in the lateral view and in 95% in AP view. Deficiencies in cement mantle were noted in very few cases, zones 6 & 13 had the highest incidence but even here only 9% of cases had inadequate cementation.

We find the centralisers a useful adjunct in cemented hip arthroplasty.

Introduction and Aims: Our experience with over 200 cases of Avon patellofemoral replacement (PFR) in the elderly with severe arthritis has been satisfactory, so we have extended the indications to younger patients with severe symptoms and various pathologies.

Method: Sixty-six knees in 53 patients (10M: 46F) under the age of 55 years (average 47 years) have been treated with an AVON PFR for the following conditions:

PATHOLOGY NUMBER of Knees

Isolated lateral facet OA 34

Failed realignment 12

Persistent subluxation/dislocation 5

Trochlear dysplasia 5

Pure chondral disease 3

Failed carbon fibre implant 3

Post-patellectomy instability 3

Post-traumatic pain 1

All patients were recorded prospectively and have been regularly reviewed using the modified Oxford, Bartlett & Bristol Knee scoring systems. The mean follow-up of the group is 24 months.

Results: No patient has been lost to follow-up, all knee scores improved substantially.

Most of the patients retained their range of flexion and the mean range of movement increased from 112 to 122 degrees. Patients with persistent subluxation were the most dramatically improved. There have been no cases of deep infection, loosening or wear.

Conclusion: Avon PFR provides a reliable short-term solution to some of the more difficult and disabling problems of the patello-femoral joint as long as demonstrable pathology is present.

Purpose A new design of patello-femoral arthroplasty has been used to treat patients under 55 years suffering severe symptoms from chondral and early arthritic disease of the patello-femoral joint.

Materials and Methods and Results Fifty-two patello-femoral arthroplasties were performed in 45 patients under the age of fifty-five years when other treatments had failed. The average age was 48 years (range 36–54 years). Thirty-seven cases had undergone previous surgery for a variety of conditions, and the causes of the disorders were analysed. Results were assessed using pain scores and Bartlett’s and Oxford functional scores. 35 cases were reviewed at 8 months and 22 cases at two years. The median pain score improved from 10/40 points to 35 at two years. The Bartlett score increased from 10/30 points to 27 and the Oxford score from 19/48 points to 35 at two years. The range of movement increased from 114° to 121°. There have been no cases of deep infection, loosening, wear or instability. Disease progression, a potential risk has occurred in one case.

Conclusions This prosthesis offers a solution in younger patients with disabling symptoms of isolated early patello-femoral disease who have not responded to conservative surgical management.