Objective: The purpose of this report is to describe the clinical, radiographic, and diagnostic ultrasound findings in a patient who sustained a type III Salter-Harris fracture of the first proximal phalanx.
Clinical Features: A 14-year-old male baseball player presented to a chiropractic clinic with a 2-day history of proximal thumb pain, which began following a forceful hyperabduction injury while sliding into base. Thenar swelling was evident on clinical examination, and both active and passive thumb motions were painful in all directions.