Comparison of the rate of delayed/nonunion in fifth metatarsal fractures receiving anti-inflammatory medications

PURPOSE: Controversy exists regarding the acute effect of non-steroidal anti-inflammatory drugs (NSAIDs) on early fracture healing. The purpose of this study was to analyze the rate of nonunion or delayed union in patients with fifth metatarsal (5(th) MT) fractures. We hypothesize that the use of NSAIDs would increase the rate of nonunion/delayed union in 5(th) MT fractures. METHODS: Using PearlDiver, a national insurance database was analyzed. ICD codes were used to identify patients diagnosed with 5(th) MT fracture from 2007-2018. Patients were grouped by initial management (nonoperative vs. open reduction and internal fixation (ORIF) or non/malunion repair within 60 days) and sub-grouped by whether they had been prescribed at least one pre-defined NSAID. Subsequent ORIF or nonunion/malunion repair operative intervention was used as a surrogate for fracture nonunion/delayed union. RESULTS: Of the 10,991 subjects with a diagnosis of 5(th) MT, 10,626 (96.7%) underwent initial nonoperative treatment, 1,409 of which (13.3%) received prescription NSAIDS within 60 days of diagnosis. 16/1,409 (1.14%) subjects who received anti-inflammatory prescriptions underwent ORIF or repair of non/malunion at least 60 days after diagnosis while 46/9,217 (0.50%; P=0.003483) subjects who did not receive anti-inflammatory prescriptions underwent ORIF or repair of non/malunion at least 60 days after diagnosis. In the 365 subjects who underwent early repair/ORIF (within 60 days), there was no significant difference in the rate of nonunion/delayed union. CONCLUSION: The rate of nonunion/delayed union of 5(th) MT fractures was significantly higher in subjects receiving NSAIDs within 60 days of initial diagnosis in patients managed non-operatively. LEVEL OF EVIDENCE: Level III