Shortening of the First Ray After First Tarsometatarsal Joint Fusion: A Cadaveric Comparison Between Curettage Versus Planal Resection

Abstract

Category: Bunion; Midfoot/Forefoot; Other Introduction/Purpose: Potential shortening of the first ray is an important consideration when performing a first tarsometatarsal (TMTJ) fusion. However, no previous study has sought to directly quantify the resultant shortening after TMTJ fusion. The purpose of the present anatomic study was to directly assess and compare shortening of the first ray using two joint preparation techniques (curettage, planal resection) for first TMTJ fusion. Methods: Ten pairs of matched lower extremity cadaver specimens were divided into two groups. Preoperative length assessments were performed at the first TMTJ dorsally and plantarly using a digital caliper. In Group 1, joint preparation for first TMTJ fusion was performed with curettage, whereas specimens in Group 2 underwent planal resection. Post-operative length assessments were repeated. All data was analyzed using two-tailed Students t-tests. Results: Mean shortening of the first ray following curettage was 1.1 (range, 0.3 to 2.0) mm dorsally and 1.6 (range, 0.6 to 3.7) mm plantarly; while mean shortening following planal resection was 4.5 (range, 2.7 to 7.9) mm dorsally and 4.6 (range, 2.4 to 8.9) mm plantarly. The measured differences were statistically significant (p <0.001, p=0.001). Conclusion: Both curettage and planal resection resulted in shortening of the first ray after first TMTJ fusion. Planal resection resulted in significantly more shortening, which was also more variable. Surgeons performing first TMTJ fusions may consider curettage over planal resection to mitigate the risk of painful postoperative transfer metatarsalgia.