Minimally Invasive Floating Metatarsal Osteotomy – A Novel Method for Neuropathic Diabetic First Metatarsal Ulcers

Background: Recalcitrant diabetic foot ulcers under the first metatarsal (MT1) head are common. Offloading is the main treatment, and can usually be achieved with orthotics and appropriate shoes or casts. When conservative treatment fails, offloading surgery may be indicated. There are very few reports on surgical procedures for offloading MT1. Floating MT1 osteotomy for offloading ulcers has never been reported. Advanced minimally invasive foot surgery (MIS) utilizes low speed and high torque burr drills which minimize damage to nerves and blood vessels. Applying MIS in patients with diabetic foot ulcers can enable deformity correction and ulcer healing with minimal soft tissue damage and post-surgical complications.

Methods: We performed a retrospective chart review on diabetic patients who underwent a minimally invasive floating first metatarsal osteotomy for the treatment of recalcitrant or recurrent neuropathic plantar metatarsal head ulcers between 2016 and 2017.

Results: Fifteen patients had MIS of MT1 for ulcers under the MT1 head between June 2016 and June 2017 operated by one surgeon. All ulcers were initially classified as Texas A1. Following surgery, all ulcers healed without recurrence and with the normalization of the skin below the MT1 head with no callus formation. Mean time to heal was 3.4 weeks. There were 4surgical site infections (26%), all of which were mild, did not require surgical treatment and resolved with oral antibiotics. One drill broke, which compelled open surgery. One patient developed transfer metatarsalgia.

Conclusions: This is the first report of a novel surgical method using MIS floating osteotomy of MT1 for the treatment of recalcitrant or recurrent neuropathic plantar metatarsal head ulcers. The technique proves to be curative and prophylactic, while also being relatively safe. Our complication rate is by far less that the natural history of recalcitrant diabetic foot ulcers.