Aims: We performed a prospective study on 105 knees following a selective approach to patellar resurfacing in cruciate retaining total knee replacements, and report the þve year results of both groups. Methods: We performed a prospective study on 129 knees with a selective approach to patellar resurfacing. 105 knees were followed up at an average of 57 months. Of these, forty eight knees met the eligibility criteria, thus leaving 57 knees with unresurfaced patellas. Mean follow up was 57 months. Parameters studied included HSS scores, pain, function, range of motion and patellofemoral symptoms including the ability to rise from a chair and to negotiate stairs. Results: Approximately 90% good to excellent results were observed in both groups. The incidence of anterior knee pain and patellofemoral related problems was lower than the average reported in literature. None of the knees was revised for patellofemoral problems. Conclusions: Our þndings suggest that the results of patellofemoral resurfacing with modern TKR designs are dependent on a careful patient selection and meticulous surgical technique. With a selective approach to resurfacing, one can achieve a high percentage of good results in both groups. Post operative anterior knee pain is probably not related to the fact as to whether the patella is resurfaced or not.

We randomised 129 knees which were to be replaced using a standard posterior-cruciate-ligament (PCL)-retaining cemented total knee replacement into two groups. In one the PCL was retained in the normal way and in the other it was resected. They were well matched, with a predominance of women, and a mean age of 67 years.

There was no statistically significant difference in the Hospital for Special Surgery scores at a mean of 57 months (56 to 60) between the two groups although 21 patients (24 knees) were lost to follow-up. Relief from pain, correction of deformity, range of movement, stability and strength were comparable in both. Radiological assessment showed femoral rollback in approximately 20% of knees with a slightly higher incidence in the PCL-resected group. There was no significant loosening detected in either group at review at two years.

At five years, one knee in the PCL-retained group had been revised because of infection and one patient in each group was awaiting revision for loosening.

Our findings have shown no significant difference in the five-year results for a PCL-retaining total knee replacement if the PCL is excised or preserved. This suggests two important points. First, the PCL is not functional in most patients with a total knee replacement even when retained. Secondly, patients with an excised PCL show a good result with a PCL-retaining implant, thereby questioning the need for a posterior stabilised design in such a situation.

The aim of this study was to determine prospectively whether a lateral capsular approach to the knee joint for the purposes of total knee arthroplasty confers any advantage over the traditional medial capsular approach.

One hundred consecutive valgus osteoarthritic knees with greater than 10′ deformity were randomised into two groups each using a different surgical approach to the knee joint but all patients receiving the same type of arthroplasty components. One group had the replacement arthroplasty utilising a standard medial para-patellar approach and incorporating a lateral retinacular release where required whilst the other group received a modified lateral capsular approach avoiding osteotomy of the tibial tubercle and repositioning vastus lateralis at closure. Both groups were well matched in terms of age and sex. Each patient was reviewed in a special clinic at one year post-op to establish functional outcome and to review post-operative complications and length of stay and to conduct a radiological assessment of the implant. Pre and post-operative assessment utilised the HSS and Oxford knee scores. The assessor (a research physiotherapist) was blinded to the randomisation.

Results: All one hundred patients will have had their twelve month follow-up by February 2002. The results of the first 67 knees have been analysed in a preliminary study. The knee post-operative HSS and Oxford scores for the medial capsular group were 77.4 and 26 respectively and for the lateral capsular group 81.2 and 26.8. 79.4% of the patients in the medial group and 88% of patients in the lateral group showed good to excellent results on HSS scoring. Average patient satisfaction on a scale of 10 was 7.9 for the medial group and 8.5 for the lateral group. Other criteria such as range of motion, correction of deformity and stability were comparable in the two groups but it was noted that there was a tendency to use more constrained implants in the medial group. The differences between the two sets of results are not statistically significant in this preliminary report. There was no increase in wound complications in the lateral group despite incomplete closure of the capsule.

Conclusion: The lateral capsular approach for replacement arthroplasty of the valgus arthritic knee is as safe and effective as the medial capsular approach. The lateral capsular approach appears to have some advantages in certain situations such as severe and unstable deformity associated patello-femoral maltracking and also appears to enable the use of less constrained implants.

67 knees (47 patients) with a valgus deformity of more than 10° suitable for total knee replacement were randomised to two different approaches. One group (36 knees) had their knees replaced by the standard medial para-patellar approach, whilst the other (31 knees) received a modified lateral approach (without an osteotomy of the tibial tubercle and with repositioning of the contracted vastus lateralis). Both groups were well matched with a predominance of females and mean age of 67 years. The average follow up was 29 months.

Patients were assessed both pre and post operatively by the HSS (Hospital for Special Surgery) and Oxford knee scores, radiologically by weight bearing AP and lateral radiographs and by patient satisfaction scores on a scale of 10. The mean pre operative HSS and Oxford scores for the medial group were 35.3 and 46.3 respectively and for the lateral group were 35.3 and 46.3 respectively. The mean post operative HSS and Oxford scores for the medial group were 77.4 (mean improvement of 41.4 points) and 26 respectively and for the lateral group was 81.2 (HSS score, mean improvement of 45.9 points) and 26.8 (Oxford score). 79.4% of patients in the medial group and 88% of patients in the lateral group showed good to excellent results (using the HSS scoring system).

At two years none of the knees were radiologically loose or mal aligned. Average patient satisfaction on a scale of 10 was 7.9 for the medial group and 8.5 for the lateral group. One patient reported no relief of pain and an acute limitation of function at two years. She suffers from severe Parkinson’s disease and disabilities arising from multiple joint pathologies. There was no incidence of an early or late infection.

Pain relief, range of motion, deformity correction and stability were comparable in the two groups.

The results suggest that a lateral capsular approach for the replacement of valgus knees may give higher knee scores than a conventional medial approach. The differences between the two sets of results are not however statistically significant. There was no increase in wound complication in the lateral group despite incomplete closure of the capsule.

The lateral capsular approach is as safe and effective as the medial capsular approach for replacement of the valgus osteoarthritic knee.