CHANGE IN BMI AFTER MID-FOOT AND HIND-FOOT ARTHRODESIS- A RETROSPECTIVE REVIEW OF PROSPECTIVELY COLLECTED DATA

Abstract

Painful foot and ankle joints are often pointed out as an impeding factor for lack of mobility and weight reduction. There is an assumption that weight loss will occur after their surgery due to increased mobility. The current study aimed to evaluate the effect of surgery on post-operative body mass index (BMI) in patients who underwent mid-foot or hind-foot arthrodesis. Our secondary aim was to look at the effect of sex, pre-operative obesity and good pain relief (AOFAS> 80) on post-operative BMI.

All patients who underwent mid-foot and hind-foot arthrodesis between April 2005 and November 2006 were identified from the operating theatre records. Each patient’s BMI recorded pre-operatively was compared with that recorded at a minimum of 6 months postoperatively using the paired Student’s t-test.

There were 35 eligible patients. 3 patients were excluded because of multiple trauma and 1 patient died during the period of study. We had 31 patients with 33 procedures with a mean age of 61 years (range 41–80). There were 18 females and 13 males. It was found that there was a mean increase of BMI by 0.25 (95%CI of −.95 to.44; p-value=0.47). It was noted that BMI of patients in obese group (BMI> 30) increased post-operatively by 0.07 (95%CI of −1.52 to 1.66; p-value=0.92).

This study highlights the fact that there is no significant effect on BMI in obese patients after successful fusion surgery. The post-operative BMI is neither significantly affected by sex nor quality of pain relief.