Minimally invasive vs open distal metatarsal osteotomy for hallux valgus - A systematic review and meta-analysis

Numerous publications of the late 20th century have presented the radiological outcome of open technique for distal metatarsal osteotomy for mild to moderate hallux valgus and the clinical outcomes by means of well-established scoring systems which have been published and make these open techniques today's benchmark and gold standard. Minimally invasive procedures reduce surgical trauma because they are performed without large incisions, and injury to the soft tissues is limited. This has the theoretical advantages of improved recovery and decreased rehabilitation times. There is however limited literature to prove the same for minimally invasive surgery for hallux valgus.Our aim was thus to pool all available comparative literature on minimally invasive hallux valgus surgery done for mild to moderate hallux valgus versus open surgical approaches.

A PubMed, Embase and Scopus search was performed using the keywords ('hallux valgus' OR bunion) AND ('minimally invasive' OR percutaneous) AND osteotomy. A total of 473 records were identified and out of which nine studies were included in the final review.

Most available studies are either randomized control trials, or prospective cohort studies providing good level of evidence. Radiological analysis showed similar correction with both MIS and open osteotomies. In functional analysis results were different with open techniques providing better results in terms of AOFAS score. (p < 0.0001). VAS score and complication rate were similar in both groups.

We conclude that based on available literature MIS provides equivalent radiological outcomes with respect to open surgery but functionally despite the promising results (good to excellent in most series), the outcomes in terms of function are not as good as open surgery. MIS techniques provide satisfactory outcomes for mild-to-moderate severity of hallux valgus though not as good as open surgery. There is evolving literature for this relatively new procedure. Longer duration of follow up and bigger numbers would allow for more meaningful data analysis and conclusions to be drawn as more studies come forward.