A Rare Case of Monteggia Bado Type II Fracture-Dislocation with Finger Drop

Abstract

Monteggia fractures, defined as ulnar fractures accompanied by radial head dislocation, are rare injuries in adults and are often complicated by neurovascular deficits. Among the Bado classifications, type IIlesions—posterior dislocation of the radial head with proximal ulna fracture—are most frequently encountered in adults, yet associated posterior interosseous nerve (PIN) palsy is uncommon. We report thecase of a 34-year-old female presenting with acute pain, swelling, and restricted motion of the left elbow following a self-fall. Clinical examination revealed deformity, tenderness, restricted range of motion,and finger drop consistent with PIN palsy, while wrist extension remained intact. Radiographs confirmed a Monteggia fracture-dislocation, Bado type II. The patient underwent open reduction and internalfixation with plating, followed by application of a cock-up splint for finger drop. Postoperative imaging demonstrated satisfactory reduction.
This case underscores the diagnostic challenge posed by Monteggia lesions, which may present subtly yet carry significant functional implications if associated with nerve injury. PIN palsy typically arisesfrom traction or compression of the nerve following radial head displacement, manifesting as an inability to extend fingers at the metacarpophalangeal joints. Literature suggests that early recognition,anatomic reduction of the ulna, and restoration of radial head alignment are critical for spontaneous resolution of neuropraxia. Surgical fixation with modern low-profile locking plates offers biomechanicaladvantages, particularly in complex fracture patterns, and has been associated with favorable outcomes and reduced hardware complications.
Our case highlights the importance of vigilant neurovascular assessment in Monteggia fractures, given the limited epidemiological data and scarce guidelines on optimal management of associated nerveinjuries. Although prognosis is generally favorable with timely intervention, missed diagnosis or delayed treatment may result in persistent deficits and poor functional recovery. Early physiotherapyfollowing stabilization is vital for neurological improvement. This report adds to the limited literature documenting PIN involvement in Bado type II Monteggia fractures and emphasizes the need forindividualized surgical and rehabilitative strategies.