Narrative review tracing how evolving understanding of first TMT anatomy and three-dimensional hallux valgus mechanics has driven progressive changes in Lapidus technique and fixation. Covers indications for modified versus traditional Lapidus, intraoperative decision-making under stress fluoroscopy, and biomechanical comparisons of crossed screws, plates, nitinol staples, and intramedullary fixation. Answers the question: why is first TMT fusion uniquely capable of correcting hallux valgus, and what fixation construct best maintains that correction?
The Lapidus procedure has historically been underutilized because its indications were narrowly defined as sagittal-plane hypermobility only. This review reframes hallux valgus as a three-dimensional deformity driven substantially by first metatarsal pronation, explaining why patients can recur even after technically adequate intermetatarsal angle correction.
In practice: when you see residual sesamoid subluxation on postoperative X-ray after a Lapidus, ask whether the metatarsal was supinated during the procedure. An Akin osteotomy added at the end corrects hallux rotation but does not address the more proximal pronation deformity.
For fixation decisions: use stress fluoroscopy after every first TMT fusion before closing. Visible intercuneiform gapping means you need to add first-to-second ray fixation. The first-to-second metatarsal screw specifically controls transverse and coronal plane instability; the additional cuneiform screw alone is not sufficient.
Avoid the claw plate for Lapidus fixation. Nitinol staples and plantar plate-plus-lag-screw constructs are biomechanically superior for maintaining compression and preventing plantar gapping.
Narrative review tracing how evolving understanding of first TMT anatomy and three-dimensional hallux valgus mechanics has driven progressive changes in Lapidus technique and fixation. Covers indications for modified versus traditional Lapidus, intraoperative decision-making under stress fluoroscopy, and biomechanical comparisons of crossed screws, plates, nitinol staples, and intramedullary fixation. Answers the question: why is first TMT fusion uniquely capable of correcting hallux valgus, and what fixation construct best maintains that correction?
The Lapidus procedure has historically been underutilized because its indications were narrowly defined as sagittal-plane hypermobility only. This review reframes hallux valgus as a three-dimensional deformity driven substantially by first metatarsal pronation, explaining why patients can recur even after technically adequate intermetatarsal angle correction.
In practice: when you see residual sesamoid subluxation on postoperative X-ray after a Lapidus, ask whether the metatarsal was supinated during the procedure. An Akin osteotomy added at the end corrects hallux rotation but does not address the more proximal pronation deformity.
For fixation decisions: use stress fluoroscopy after every first TMT fusion before closing. Visible intercuneiform gapping means you need to add first-to-second ray fixation. The first-to-second metatarsal screw specifically controls transverse and coronal plane instability; the additional cuneiform screw alone is not sufficient.
Avoid the claw plate for Lapidus fixation. Nitinol staples and plantar plate-plus-lag-screw constructs are biomechanically superior for maintaining compression and preventing plantar gapping.