"In Situ" Joint Preparation Technique for First Metatarsophalangeal Arthrodesis: A Retrospective Comparative Review of 388 Cases

"Cup-shaped power reamers" and "flat cuts" (FC) are common joint preparation techniques in first metatarsophalangeal (MTP) joint arthrodesis. However, the third option of an "in situ" (IS) technique has rarely been studied. This study aims to compare the clinical, radiographic, and patient-reported outcomes (PROMs) of the IS technique for various MTP pathologies with other MTP joint preparation techniques. A single-center retrospective review was performed for patients who underwent primary MTP joint arthrodesis between 2015 and 2019. In total, 388 cases were included in the study. We found higher nonunion rates in the IS group (11.1% vs 4.6%, p = .016). However, the revision rates were similar between the groups (7.1% vs 6.5%, p = .809). Multivariate analysis revealed that diabetes mellitus was associated with significantly higher overall complication rates (p < .001). The FC technique was associated with transfer metatarsalgia (p = .015) and a more first ray shortening (p < .001). Visual analog scale, PROMIS-10 physical, and PROMIS-CAT physical scores significantly improved in IS and FC groups (p < .001, p = .002, p = .001, respectively). The improvement was comparable between the joint preparation techniques (p = .806). In conclusion, the IS joint preparation technique is simple and effective for first MTP joint arthrodesis. In our series, the IS technique had a higher radiographic nonunion rate that did not correlate with a higher revision rate, and otherwise similar complication profile to the FC technique while providing similar PROMs. The IS technique resulted in significantly less first ray shortening when compared to the FC technique.