PURPOSES

Previous studies on patella-femoral morphology have suggested patella maltracking plays an important part in the aetiology but there had been no studies correlating maltracking with articular cartilage change.

We report the results of a modified Fulkerson technique of antero-medialisation of the tibial tubercle, combined with microfracture or abrasion arthroplasty in patients under 60 with patello-femoral osteoarthritis.

All patients operated on between September 1992 and October 2007 were reviewed by an independent observer in clinic or by postal questionnaire, using the Oxford Knee Score, Melbourne Patella Score and a Satisfaction Score. Only patients with Outerbridge Grade 3 – 4 osteoarthritis of the patello-femoral joint were included. They were assessed pre-operatively with plain x-rays, MRI scans (as well as tracking scans in the last 10 years) and arthroscopically. All patients with tracking scans showed lateral subluxation of the patella.

The surgical procedure was a modification of Fulkerson's tibial tubercle osteotomy, with an advancement of 1-1.5 cms and a medialisation of 1.5 cms. The exposed bone of the patella and trochlea was drilled in the early cases and in the later cases an arthroscopic microfracture or abrasion using a power burr was carried out.

Between September 1992 and October 2007, 103 procedures were carried out in 84 patients, 19 patients having staged bilateral procedures. The mean follow up was 84 months (range 24 – 204 months). The mean age was 45 (range 26 – 59) and the female to male ratio was 7.6:1. 70 patients were reviewed giving a follow up rate of 82%. The mean Oxford Knee Score was 18.5 pre-operatively (range 3- 32) and 34.3 post-operatively (range 11- 47). The Melbourne Patella Score was 9.6 pre-operatively (range 3- 30) and 20 post-operatively (range 11- 30). Patient Satisfaction Scores were excellent (54%), good (29%), fair (8.5%) and poor (8.5%). 4 knees in 3 patients were converted to a patello-femoral arthroplasty, giving a 10 year survival rate of 96.1%.

This procedure offers an alternative to patello-femoral arthroplasty for younger patients with isolated patello-femoral arthritis.

The purpose of the study was to investigate the outcome of Oxford medial unicompartmental knee replacement (UKR) in patients over 70 years old and also to assess their ability to kneel.

We identified from our prospectively collected knee database 90 patients (98 knees) undergoing Oxford medial UKR who were 70 years or older on the day of surgery.

Oxford Knee Scores (OKS) were collected pre-operatively and also post-operatively at the following intervals: 3 months, 6 months, 1 year, 2 years, 5 years and then annually after this.

The mean patient age at surgery was 73.2 years (range 70.2 – 84.3 years). The OKS pre-operatively had a mean of 35.8/60 (range 22-55) and improved to 23.6/60 post-operatively (range 14-34). Patient follow-up was 44.3 months and ranged from 12-111 months. Two patients were lost to follow-up, 1 was converted to a total knee replacement and 3 died of causes unrelated to the knee surgery. 91.7% of patients still had their original prostheses at last follow-up.

Forty percent of patients stated they were able to kneel pre-operatively which improved to 50.2% postoperatively. This was consistent throughout all the follow up intervals that were assessed. Specific kneeling score from the OKS showed no statistically significant change with a mean of 3.94/5 pre-operatively and a mean of 3.54 averaged over all the post-operative follow up intervals.

We conclude that medial Oxford UKR is a reliable operation in patients over 70 years old. Previous studies include a younger age group which potentially encourages the less familiar surgeon to use a UKR for the young active patient but continue with a total knee arthroplasty for the older patient. Our study suggests age should not be a factor when considering performing Oxford UKR. Ability to kneel is not altered significantly by UKR in this age group.