Summary Hamate Body Fractures are rare carpal fractures that can be associated with 4th or 5th metacarpal fractures. Diagnosis is generally made with radiographs of the wrist but may require CT for confirmation. Treatment is nonoperative for non-displaced fractures but displaced or intra-articular fractures require ORIF. Epidemiology Incidence < 2% of all carpal fractures Etiology Pathophysiology mechanism of injury main cause for these lesions is a direct impact against a hard surface with a clenched fist Associated conditions 4th or 5th metacarpal base fractures or dislocations present in ~ 15% Hook of Hamate fractures Anatomy Osteology triangular shaped carpal bone composed of hook and body Location most ulnar bone in the distal carpal row Articulation 4th and 5th metacarpals capitate triquetrum Classification Milch Classification Type I Hook of hamate fx (most common) Type I-I Avulsion Type I-II Middle of hook Type I-III Base of hook Type II Body of hamate fx Type IIA Coronal Type IIB Transverse Presentation Symptoms ulnar-sided wrist pain and swelling Physical exam inspection focal tenderness over hamate Imaging Radiographs recommended views PA lateral ER oblique best view to see hamate body fractures carpal tunnel CT usually required to delineate fracture pattern and determine operative plan Differential Hook of Hamate fracture Pisiform fracture Metacarpal shaft fractures Diagnosis Radiographic diagnosis confirmed by history, physical exam, and radiographs Treatment Nonoperative immobilization indications may be used for extra-articular non-displaced fracture Operative ORIF indications most fractures are intra-articular and require open reduction technique interfragmentary screws +/- k-wires for temporary stabilization Techniques Open Reduction Internal Fixation approach dorsal most common approach fixation technique fixation may be obtained with K wires or screws postoperative care immobilize for 6-8 weeks Complications Stiffness Malunion Infection