It has been suggested that minimal incision surgery for hip arthroplasty allows earlier mobilisation and reduces hospital stay. Intensive post-op physiotherapy may also have the same effect. This study aimed to assess which was the more important factor.

The study compared 45 patients (26 NHS and 19 private) undergoing primary total hip arthroplasty using a standard posterior approach to 51 patients (29 NHS and 22 private) with a minimal incision of 10cm or less. Physiotherapy involved once daily weekday sessions with the NHS patients (five sessions per week) versus twice daily with the private patients (14 per week). We compared demographics, incision length, post-operative stay, complication rates and Oxford Hip Scores between the four groups.

Results showed no significant difference in age, sex and BMI between the groups. There was a significant difference (p = 0.0002) in mean scar length between the mini and standard incision groups (15.3 vs. 8.3 cm). There was no significant difference in post-op stay between the mini and standard incision NHS patients or the mini and standard incision private patients. There was a significant difference (p = 0.003) in stay between NHS and private patients (11.4 vs. 7.9 days) regardless of the incision used. There were four (4%) early dislocations, three in the mini incision group. Eleven patients received prophylactic antibiotics compared to five in the standard groups for prolonged wound ooze (> 5 days); only one patient had a proven superficial infection. There was no significant difference in the change in the Oxford Hip Scores between any of the groups.

This study suggests that intensive physiotherapy can significantly reduce in-patient stay but minimal incision surgery itself does not. The higher dislocation rate in the mini incision group demonstrates the learning curve for this technique.