Introduction First metatarsal explosion is a new serious postoperative complication that occurs with new minimally invasive bunion surgery and has yet to be reported or analyzed. This retrospective study investigated associated factors. We present a classification system (3 Types), mechanism and treatment paradigm. Methods A case review was performed between January 2018 to May 2022 and we identified 16 feet (15 patients) with metatarsal explosion. We evaluated age, sex, BMI, laterality, preoperative intermetatarsal angle, medical comorbidities, screw placement, number of screws and patterns of fracture. Results The median age was 61.6 years and 80% of patients were females. Forty percent were obese. Forty percent had thyroid disorders. One patient had bilateral explosion. The metatarsal explosion distributions were Type I 50%, Type II 31% and Type III 19%. Twelve feet (75%) of metatarsal explosions occurred in a region we coin the Cortical Purchase Zone (CPZ). Forty three percent of metatarsal explosions had screws starting distal/dorsal in the metatarsal base, a region we coin the Cancellous Anchor Zone (CAZ). Metatarsal explosion distribution was not significantly associated with age, gender, laterality, preoperative intermetatarsal angle, screw placement and all medical comorbidities. Worse metatarsal explosions were more likely with two metatarsal screws (p < 0.05). Treatment was non-surgical for 12 feet (75%) and open reduction internal fixation for 4 feet (25%). Conclusion Metatarsal explosion has three distinct types and we present a new classification system. Two screw fixation was more likely to have a metatarsal explosion. Etiologic observations suggest screw placement as a contributing cause. Treatment was mainly non-operative and surgery was utilized for unstable displaced explosions.