Risks of injury in distal metatarsal minimally invasive osteotomy when comparing standard and modified techniques: A cadaveric study

Abstract

Background: The objectives of the study were to evaluate the structures at risk in distal metatarsal mini-invasive osteotomy (DMMO) and to compare standard and intraosseous approaches.

Methods: DMMO was performed on the second and fourth metatarsals of 11 fresh-frozen cadaveric specimens. The standard technique was performed in 11 metatarsals. It was then compared to a modified intraosseous technique that entails starting inside the bone in 11 other metatarsals. The cadavers were dissected to identify unintentional injury to soft tissue structures.

Results: In the standard group the most injured structures were the metatarsal joint capsules (MJC) (27%), extensor digitorum longus (EDL) (18%), and extensor digitorum brevis (EDB) (9%). The modified intraosseous group injured the EDL (27%), not the MJC (0%) and the EDB (0%). Distances between osteotomies and the dorsal metatarsal head articular surface (DMHAS) were 6.08 ± 3.99 mm in the standard and 9.92 ± 3.42 mm in the modified (p = 0.02).

Conclusion: The DMMO techniques most frequently injured the EDL. Intra-articular positioning of the osteotomy was more observed in the standard. Overall, it appears the modified method could be an alternative to the standard DMMO.

Clinical relevance: The modified minimally invasive DMMO has a comparable rate of potential iatrogenic injuries. This intraosseous procedure may present as an option when planning surgery to the lesser metatarsals.

Level of evidence: Level III. Comparative Cadaveric Study.

Keywords: Anatomic study; Cadaveric; DMMO; Distal metatarsal mini-invasive osteotomy; Iatrogenic; Injury; Metatarsalgia; Minimally invasive; Osteotomy.