The short radiolunate ligament is a stout palmar radiocarpal ligament running from the lunate facet of the distal radius directly to the proximal pole of the lunate. It is the shortest and most direct of the palmar radiocarpal ligaments and forms a critical sling that maintains the lunate in its carpal position during wrist loading. Together with the long radiolunate and the radioscaphocapitate, it constitutes the primary palmar radiocarpal stabilising complex.
Directly supports the lunate against dorsal and radial displacement, and serves as the primary check ligament preventing lunate dislocation during forced wrist extension. It is the key stabiliser that, when torn, permits progression from perilunate to lunate dislocation.
The short radiolunate ligament is the last structure to fail in the progressive perilunate instability sequence described by Mayfield. When this ligament ruptures after failure of the scapholunate, lunotriquetral, and dorsal radiocarpal ligaments, the lunate dislocates palmarly and the remaining carpus displaces dorsally, producing the classic perilunate dislocation pattern. Preservation and repair of this ligament during complex wrist reconstruction is critical for restoring carpal kinematics.
Progressive carpal instability from high-energy hyperextension injury culminates in short radiolunate ligament rupture, allowing the lunate to eject palmarly into the carpal tunnel, producing median nerve compression, and requiring urgent closed or open reduction.
In Mayfield's classification, short radiolunate failure defines Stage IV, the most severe injury pattern, associated with near-total carpal ligament disruption requiring ligament repair, temporary fixation, and prolonged rehabilitation.
