Minimally invasive total knee arthroplasty is purported to have a number of patient benefits: reduced post-operative pain, earlier mobilisation, and shorter in-patient stay.

However, previous literature has identified the existence of a learning curve that may render the procedure unsuitable for low-volume arthroplasty surgeons.

Via retrospective analysis, we set out to compare the incidence of major and minor complications during the first eighty-four minimally invasive total-knee replacements (NexGen; Zimmer UK) undertaken by a single high-volume arthroplasty surgeon starting in April 2004.

The eighty-four patients were sub-divided into four chronological groups (twenty one patients each, designated A, B, C & D respectively). Fifty-three patient records were available for analysis. These comprised: Group A (n=17), Group B (n= 13), Group C (n= 10), and Group D (n=13), with a mean follow-up of 21 months.

Three patients had rheumatoid arthritis, whilst the remaining fifty had osteoarthritis.

There were two major and five minor complications in Group A, one major complication in Group B, one major and one minor complication in Group C, and two minor complications in Group D. Employing a Turkey post hoc ANOVA test, no significant differences were found between the groups when comparing overall complications, or when comparing minor and major complications as separate entities (PASW Statistics 17 for Windows, Chicago, Illinois).

To conclude, although a higher complication rate was observed in this group of patients during the first twenty minimally invasive total knee arthroplasties, this difference was not statistically significant. A follow-up study will analyse the postoperative results of a more recent cohort of patients.

We studied prospectively 30 patients who had a Mitchell’s osteotomy secured by either a suture followed by immobilisation in a plaster boot for six weeks, or by a cortical screw with early mobilisation.

The mean time for return to social activities after fixation by a screw was 2.9 weeks and to work 4.9 weeks, which was significantly earlier than those who had stabilisation by a suture (5.7 and 8.7 weeks, respectively; p < 0.001). Use of a screw also produced a higher degree of patient satisfaction at six weeks, and an earlier return to wearing normal footwear. The improvement in forefoot scores was significantly greater after fixation by a screw at six weeks (p = 0.036) and three months (p = 0.024). At one year, two screws had been removed because of pain at the site of the screw head.

Internal fixation of Mitchell’s osteotomy by a screw allows the safe early mobilisation of patients and reduces the time required for convalescence.