Category: Bunion; Midfoot/Forefoot Introduction/Purpose: First metatarsophalangeal joint (MTPJ) arthrodesis is a commonly performed procedure for patients with various disorders of the first ray including hallux rigidus, severe hallux valgus, failed 1st MTPJ replacement, and failed hallux valgus correction. Outcomes are generally favorable and similar outcomes have been shown in the young and elderly. It is well documented that medical comorbidities have deleterious effects on outcomes in foot and ankle surgery. Obesity - in particular - has been broadly studied among the foot and ankle literature and has been associated with increased complications. Presently, there is a paucity of studies examining obesity's effect on outcomes of 1st MTPJ arthrodesis. This study's purpose was to evaluate outcomes following 1st MTPJ arthrodesis in obese vs non-obese patients. Methods: A retrospective cohort study of 94 patients undergoing first MTPJ fusion over the age of 18 with a diagnosis of hallux valgus or hallux rigidus was performed. Surgical and postoperative outcomes, Visual Analog Pain scale (VAS), and Short Form 36 (SF-36) surveys were examined and stratified into 2 patient groups: BMI < 30 and 3 30, with sub-analyses conducted between Obesity class I (30-34.9) and Obesity class II (35-39.9) patients. Continueous, normally distributed data were compared with independent sample t-tests, while comparisons of categorical data were made using chi-squared tests. Alpha and beta were assumed to be 0.05 and 0.8, respectively. Results: Average overall VAS and SF-36 physical component scores improved significantly at 6 months (P< 0.0001, 0.006) and 1- year postoperative visits (P <0.0001, 0.007) following 1st MTP fusion in the cohort as a whole. No differences in VAS or SF-36 scores were found between the obese (BMI > 30) or non-obese cohorts. Amongst BMI classified subgroups, significantly greater changes in preoperative to 6-month and 1-year postoperative VAS pain were observed in the Obesity class I patients vs. Obsesity class II or greater (P=0.043, 0.022). Conclusion: Our study showed first MTPJ fusion reliably improves pain and physical quality-of-life in arthritic obese and non- obese patients without differences in nonunion, complications, or patient-reported measures. Additionally, we observed that obese patients experienced comparable improvements in VAS pain and SF-36 physical function scores as their non-obese peers. Our findings asset that first MTPJ fusion is an effective procedure for correction of MPTJ pathology in the obese.

Category: Midfoot/Forefoot; Other Introduction/Purpose: It has been well documented in the literature that fractures of the base of the fifth metatarsal are often associated with varus hindfoot alignment. Zone two fractures at the metaphyseal-diaphyseal junction, commonly referred to as Jones fractures, have specifically been noted to have a higher incidence of delayed union and nonunion. This has historically been attributed to the tenuous blood supply in this region. Although it is known that hindfoot varus may predispose to these fractures, there is little information on whether a cavovarus alignment may also contribute to the increased risk of nonunion. The purpose of this study is to determine whether cavovarus foot alignment is associated with delayed union or nonunion in Jones fractures. Methods: We identified patients who sustained a proximal fifth metatarsal fracture between the years 2016-2021 at a single academic institution. Weightbearing foot radiographs were then reviewed to identify zone 2 fractures. Talo-first metatarsal, talonavicular coverage, and talocalcaneal angles were then measured on the AP view and calcaneal pitch, talocalcaneal, and talo- first metatarsal angles were measured on the lateral view to assess foot alignment. The primary outcome measure was the presence of a nonunion or delayed union. T-tests, Mann Whitney U tests, and ANOVA analyses were conducted to assess for differences. Results: We identified a total of 117 patients with 118 zone 2 proximal fifth metatarsal fractures. Of those fractures, there were 23 of which were considered either delayed union (n=8) or nonunion (n=15). Similar rates of nonunion and delayed union were observed between patients undergoing nonoperative and operative management of their Jones fractures (p=0.514, p=0.200, respectively). For all patients with a nonunion or delayed union, no differences in anteroposterior (AP) talo-first metatarsal angle, AP talonavicular coverage angle, AP talocalcaneal angle, lateral calcaneal pitch, lateral talo-first metatarsal angle, or lateral talocalcaneal angle from those with expected healing were observed (p = 0.773, p = 0.084, p = 0.874, p = 0.751, p = 0.471, and p = 0.386 - respectively). Conclusion: Overall, no measured foot alignment values (talo-first metatarsal angle, talonavicular coverage, talocalcaneal angle, or calcaneal pitch) were statistically associated with increased risk of delayed union or non-union among patients with Jones fractures undergoing either operative or non-operative treatment. Furthermore, there was no measured difference in these foot alignment parameters between those patients undergoing operative treatment and those undergoing non-operative treatment. In conclusion, cavovarus alignment is not associated with an increased risk of non-union or delayed union in the operative or non-operative treatment of Jones fractures.