Percutaneous, MIS and open hallux valgus surgery

There is some confusion in the terminology used when referring to MIS (Minimal invasive surgery) or percutaneous surgery. The correct term to describe these procedures should be percutaneous (made through the skin) and MIS should be reserved for procedures whose extent is between percutaneous and open surgery (e.g. osteosynthesis). Minimal incision surgery may be distinguished in first, second and third generation minimal incision surgery techniques. First generation MIS hallux valgus surgery is mainly connected with the Isham procedure; an intraarticular oblique and incomplete osteotomy of the head of the first metatarsal without fixation. The Bösch osteotomy and the SERI are classified as second generation MIS hallux surgery. They are both transverse subcapital osteotomies fixed with a percutaneous medial K-wire inserted into the medullary canal. For all these procedures, intraoperative fluoroscopic control is necessary. Open hallux valgus surgery can be divided into proximal, diaphyseal and distal osteotomies of the first metatarsal. Reviewing the available literature suggests minimally invasive and percutaneous hallux valgus correction leads to similar clinical and radiological results to those for open chevron or SCARF osteotomies. First generation minimally invasive techniques are primarily recommended for minor deformities. In second generation minimally invasive hallux valgus surgery, up to 61% malunion of the metatarsal head is reported. Once surgeons are past the learning curve, third generation minimally invasive chevron osteotomies can present similar clinical and radiological outcomes to open surgeries. Specific cadaveric training is mandatory for any surgeon considering performing minimally invasive surgical techniques. Cite this article: EFORT Open Rev 2021;6:432-438. DOI: 10.1302/2058-5241.6.210029