Summary

Isolated tear of collateral ligaments of thumb are common but combined injuries of both radial and ulnar collateral ligaments are rare. These cases are reported in athletes involved in high-impact sports. Here, we report a case of a 15-year-old boy with pain at base of the thumb and instability following low-impact sporting activity. On subsequent clinicoradiological assessment, simultaneous combined complete tear of both radial and ulnar collateral ligaments of the thumb was noted. Delayed primary repair of both collateral ligaments was done. This case highlights the rarity of this type of injury in an adolescent and also the use of appropriate clinical tests and imaging modalities for early diagnosis of such injuries. Restoration of joint stability as early as possible either by repair or reconstruction of ligaments needs to be considered to prevent secondary osteoarthritis of metacarpophalangeal joint.