Orthopaedics: Forearm
Radius and Ulna Fracture
Mechanism
· commonly a FOOSH or direct blow
Investigations
· x-ray: 1) AP and lateral of forearm; 2) AP, lateral, oblique of elbow and wrist
· CT if fracture is close to joint
Treatment
· goal is anatomic reduction since imperfect alignment significantly limits forearm pronation and supination
· ORIF with compresslon plates and screws
Monteggia Fracture
Definition
· fracture of the proximal ulna with radial head dislocation
Mechanism
· direct blow on the posterior aspect of the forearm.
· hyperpronation
· fall on the hyperextended elbow
Clinical Features
· decreased rotation of forearm ± palpation lump at the radial head
· ulna angled apex anterior and radial head dislocated anteriorly (rarely the reverie deformity occurs)
Treatment
· ORIF of ulna with indirect radius reduction in 90%
· splint and early post-op ROM if elbow completely stable; otherwise immobilization in plaster with elbow flexed for 6 weeks
Specific Complications (see General Fracture Complications)
· compartment syndrome
· radial/posterior interosseous nerve (PIN) injury
· decreased ROM
Nightstick Fracture
Definition
· isolated fracture of ulna
Mechanism
· direct blow to forearm (holding arm up to protect face)
Treatment
· non-displaced: below elbow cast (10 days) followed by forearm brace (-8 weeks)
· displaced: ORIF if >5096 shaft displacement or >10° angulation
Galeazzi Fracture
Definition
· fracture of the distal radial shaft with disruption of the distal radioulnar joint (DRUJ)
· most commonly in the distall 1/3 of radius near junction of metaphysis/diaphysis
Mechanism
· usual cause is fall on the hand (mechanical axial loading ofpronated forearm)
lnvestigations
· x-rays
o shortening of distal radius >5 mm relative to the distal ulna
o widening of the DRUJ space on AP
o dislocation of radius with respect to ulna on true lateral
Treatment
· ORIF of radius
· if DRUJ is stable, splint with early ROM
· if DRUJ ill unstable, DRUJ pinning and long arm cast in supination x 6 weeks