Intercarpal ligament injuries associated with fractures of the distal part of the radius.

BACKGROUND: Soft-tissue injuries of the wrist are often not recognized in patients with distal radial fractures, yet scapholunate injuries have been reported to occur in association with as many as 54% of distal radial fractures. The true prevalence and natural history of intercarpal ligament injury are not known.
METHODS: This prospective observational study assessed the prevalence and one-year outcome of intercarpal ligament injuries in non-osteoporotic patients with displaced fractures of the distal part of the radius. The study group consisted of fifty-one patients (twenty-seven women and twenty-four men) with a median age of forty-one years (range, twenty to fifty-seven years). Patients underwent standard fracture treatment and, in addition, wrist arthroscopy was performed to identify associated carpal injuries. No ligamentous injuries were treated. Patients were reviewed at one year and underwent physical and radiographic evaluation. Patients were analyzed according to the status of the scapholunate ligament at the time of the injury and were graded with use of a modification of the Geissler classification system: Group I consisted of ten patients with a grade-3 scapholunate ligament injury, and Group II consisted of forty-one patients with a grade-0, 1, or 2 injury.
RESULTS: Patients with an increase in ulnar variance of >2 mm at the time of the injury had a fourfold increase in the risk of sustaining a grade-3 scapholunate ligament injury (p = 0.01). Radiographically, at one year, patients in Group I (grade-3 injuries) had a greater amount of static and dynamic scapholunate dissociation and a significantly greater increase in the scapholunate angle in comparison with the uninjured wrist (p = 0.006) than did those in Group II. Intra-articular fractures were associated with a twofold increase in the prevalence of scapholunate dissociation as seen radiographically at one year. The prevalence of subjective pain on examination was significantly greater in Group I than in Group II (p = 0.009). There were no significant differences between the two groups with respect to objective outcome according to range of motion and hand grip and tip pinch strengths. Lunotriquetral injuries were uncommon and did not correlate with the scapholunate injuries, fracture grade, or configuration.
CONCLUSIONS: Grade-3 scapholunate ligament tears can be associated with ulnar positive variance at the time of initial presentation of a distal radial fracture and can be associated with more scapholunate joint pain at one year. These injuries could lead to scapholunate dissociation at the time of follow-up, particularly in patients with intraarticular fractures.