The Case:
A 15-year-old boy presented to the ED with pain in his right hand after punching a television. On exam, he had pain to palpation and swelling over the ulnar side of the hand. Radiograph below:
Interpretation: A fracture of the 5th metacarpal neck with volar angulation (Boxer’s fracture).
Why it matters:
A Boxer’s fracture is a fracture of the 5th (and sometimes 4th) metacarpal neck that accounts for about 20% of hand fractures. As the name implies, the usual mechanism is force against a clenched fist, such as punching. Patients typically present with pain and swelling over the 5th metacarpal. In addition to diagnosing an open fracture, the most important exam finding is to exclude rotational deformity by making sure the flexed digits all are pointing in the same direction. On radiographs, measure the volar angulation of the fracture, noting that angulation of 70 degrees or more generally requires reduction, splinting, and orthopedic referral for possible fixation.
However, for the majority of boxer’s fracture that are without rotational deformity and are less than 70 degrees angulated, a more conservative approach to treatment is likely better. Studies suggest that buddy taping the 4th and 5th digits together and allowing early mobilization allows patients to return to function (and work) earlier (1,3). In one study, patients on the initial visit were advised that the pain will resolve gradually over 4-6 weeks and that they will likely have some loss of prominence of the 5th “knuckle”. These patients did quite well with no follow-up whatsoever (2).
Written by Dr. Colleen Andrews, MD
Cook County Health, PGY-2
Edited by Dr. Scott Sherman, MD
Assistant Program Director, Emergency Medicine, Cook County Health
References:
Martinez-Catalan, N., Parajes, S., & Llanos, L. (in press). A Prospective Randomized Trial Comparing the Functional Results of Buddy Taping Versus Closed Reduction and Cast Immobilization in Patients With Fifth Metacarpal Neck Fractures. The Journal of Hand Surgery. https://doi.org/10.1016/j.jhsa.2020.05.013
Bansal R., & Craigen, M.A.C. (2007). Fifth Metacarpal Neck Fractures: Is Follow-Up Required? Journal of Hand Surgery (European Volume), 32(1), 69-73. doi:10.1016/j.jhsb.2006.09.021
van Aaken, J., Fusetti, C., Lucchina, S., Brunetti, S., Beaulieu, J., Gayet-Ageron, A., Hanna, K., Shin, A.Y., & Hofmeister, E. (2016). Fifth metacarpal neck fractures treated with soft wrap/buddy taping compared to reduction and casting: results of a prospective, multicenter, randomized trial. Arch Orthop Trauma Surg 136, 135–142. https://doi.org/10.1007/s00402-015-2361-0