There is increasing focus on publishing comparable data for individual hospitals and surgeons. The Dr Foster website is one portal for accessing such information, and uses hospital episode statistics sent to the Department of Health. For 2008–2011 our Trust was labelled as a statistical outlier with high one year revision rates for total knee replacement; relative risk was 2.53. We examined the accuracy of this information.

According to Dr Foster's data, out of 1517 primary total knee replacements performed between April 2008 and March 2011, fifty-five were revised within one year (29 female: 26 male). This gave a revision rate of 3.6% compared to a 1.4% national average. We reviewed patient records for those labelled as revisions.

Of these cases, only one was a revision total knee replacement within one year. Forty-four had a manipulation under anaesthesia for stiffness and the remaining cases had alternative operations such as arthroscopic washout.

For our Trust, therefore, the data is inaccurate, and a patient relying on such data would be misled. Either Trusts should work with Dr Foster to improve accurate coding of data, or they should keep ownership of their data, and publish accurate figures of their own.

A prospective cohort study was undertaken to assess the success of Ossur Unloader knee brace as non-operative management of isolated medial compartment osteoarthritis.

We recruited 12 volunteers (14 knees, mean age 63) with isolated medial compartment arthritis. They were clinically assessed, demographic data and Oxford knee scores were collected before the use of the braces. At 6 months, patient satisfaction, change in symptoms and repeat Oxford scores were noted.

Improvement was noted in 5 patients (6 knees, 42%) whose mean BMI was 29. They gained confidence, knee stability and pain relief. Their mean Oxford score had improved from 28 to 41.

Bracing was unsuccessful in 7 patients (8 knees, 58%) whose mean BMI was 33. These patients were disappointed and had discontinued its regular use. Their mean Oxford score only improved from 21 to 23.

As yet no patient has undergone a knee Arthroplasty. Comparative weight bearing radiographs with and without brace reveal no change in the weight bearing alignment. 42% of the patients with a mean baseline Oxford score of above 25 and a mean BMI of below 30 responded favourably. The main causes of failure were lack of improvement in symptoms, discomfort, skin irritation and poor patient compliance.

The time at which patients should drive following total hip replacement (THR) is dependant upon recovery and the advice they are given. The Driver Vehicle and Licensing Agency (DVLA) in the United Kingdom does not publish recommendations following THR and insurance companies usually rely on medical instruction. Few studies have been performed previously and have reached different conclusions.

Brake reaction times for patients undergoing primary THR were measured pre-operatively and at four, six and eight weeks after surgery using a vehicle driving simulator at a dedicated testing centre. Patients were prospectively recruited. Ethical approval was granted. Participants included eleven males and nine females, mean age 69 years. Side of surgery, frequency of driving and type of car (automatic or manual) were documented. Patients with postoperative complications were excluded. No adverse events occurred during the study.

Statistical analysis using Friedman's test demonstrated a statistically significant difference (P=0.015) in reaction times across the four time periods. Wilcoxon test demonstrated a highly significant difference between initial and six week mean results (P=0.003), and between four and six week results (P=0.001). No significant difference was found between six and eight weeks.

Our data suggests reaction times improve until week six and significantly between week four to six. Patients making an uncomplicated recovery following primary THR may be considered safe to return to driving from week six onwards. We recommend this is clearly documented in the medical notes, and patients should check with their insurance company prior to recommencement.