Comparison of Two Techniques for Proximal Margin Analysis of Toe Amputations: A Retrospective Review

Toe amputations are a common podiatric procedure for treatment of osteomyelitis. Whether or not the surgeon obtains a surgical cure, thus resolving the infection, can be difficult to assess. Obtaining a proximal bone margin can assist the treatment team in deciding the duration of postoperative antibiotics, need for reoperation, and postoperative care. The two senior surgeons use different methods to analyze proximal bone margins. The first surgeon obtains a microbiologic culture from the remaining bone, either at the proximal phalanx or metatarsal head, following the removal of the toe to be reviewed for osteomyelitis. Per the second surgeon's technique, the pathologist only analyzes the proximal aspect of the amputated toe for presence of osteomyelitis. Our goal is to analyze the reoperation and reamputation rates between the techniques in which the proximal margin specimens are obtained. A retrospective chart review was performed on all isolated toe or partial toe amputations from March 2017 to September 2022. There were 115 patients who met inclusion criteria. Reoperation and reamputation rates were analyzed for positive and negative infection margins from intraoperative cultures. Our study found an overall 28% reoperation rate and 26% reamputation rate for the negative margins group. In the positive proximal margin group, there was an overall 48% reoperation rate and 44% reamputation rate. Our analysis did not find a statistically significant difference between the reamputation rate in the negative margins group and the reamputation rate in the positive margins group. In conclusion, our study found that a positive proximal margin for osteomyelitis exhibited a nearly double reoperation and reamputation rate compared to patients with a negative margin, and that one margin analysis technique was not inferior to the other in regards to the need for additional surgeries.