Summary Phalanx Dislocations are common traumatic injury of the hand involving the proximal interphalangeal joint (PIP) or distal interphalangeal joint (DIP). Diagnosis can be made clinically and are confirmed with orthogonal radiographs. Treatment is closed reduction and splinting unless volar plate entrapment blocks reduction or a concomitant fracture renders the joint unstable. Epidemiology Incidence common injury, especially in athletes Anatomic location PIP joint login to view 5 more bullets DIP joint login to view 2 more bullets Etiology Mechanism of injury Generally due to direct blow Fracture dislocations due to login to view 2 more bullets Associated conditions swan neck deformity nail bed injuries login to view 1 more bullet Anatomy Distal Interphalangeal Joint osteology login to view 1 more bullet stabilized by login to view 14 more bullets Proximal Interphalangeal Joint osteology login to view 1 more bullet is stabilized by login to view 14 more bullets Presentation Physical exam inspection login to view 2 more bullets motion login to view 17 more bullets neurovascular login to view 2 more bullets Imaging Radiographs recommended views login to view 3 more bullets findings login to view 3 more bullets Diagnosis Clinical and radiographic diagnosis confirmed by history, physical exam, and radiographs PIP Dislocations Introduction dorsal dislocations are more common than volar dislocations dorsal dislocations can lead to a swan neck deformity volar dislocations can lead to a boutonniere deformity Epidemiology incidence login to view 1 more bullet Classification dorsal dislocations login to view 10 more bullets volar dislocations login to view 7 more bullets lateral dislocations login to view 1 more bullet Treatment nonoperative login to view 18 more bullets operative login to view 11 more bullets Complications PIP flexion contracture (pseudoboutonniere) login to view 2 more bullets swan neck deformity login to view 2 more bullets extensor lag login to view 1 more bullet PIP Fracture-Dislocations Introduction PIPJ fracture-dislocations can be volar or dorsal volar lip fractures are the most common fracture pattern seen with dorsal dislocations highly comminuted fracture may occur, known as "pilon" Pathophysiology mechanism of injury login to view 5 more bullets Classification Hastings Classification (based on amount of P2 articular surface involvement) Type I < 30% (stable) Type II 30-50% (tenuous) Type III > 50% (unstable) Treatment nonoperative login to view 8 more bullets operative login to view 15 more bullets Technique reduction of the middle phalanx on the condyles of the proximal phalanx is the primary goal login to view 4 more bullets DIP Dislocations & Fracture-Dislocations Introduction DIPJ dislocations are usually dorsal or lateral login to view 1 more bullet often associated with open wounds due to tight soft tissue envelope Classification DIPJ dislocations login to view 4 more bullets DIPJ fracture-dislocations login to view 4 more bullets Treatment nonoperative login to view 10 more bullets operative login to view 18 more bullets Complications DIPJ stiffness mallet finger deformity login to view 1 more bullet