Tendon laxity in superior oblique palsy.

BACKGROUND: Some congenital superior oblique palsies are known to be due to anomalous or lax superior oblique tendons. This prospective study of 24 patients with a diagnosis of superior oblique palsy was performed to determine the prevalence and significance of anatomic tendon anomaly or laxity as diagnosed by traction testing of the superior oblique tendon. METHODS: Traction testing was performed on 24 consecutive superior oblique palsy patients to determine the relative laxity of the tendons. RESULTS: All 14 patients who were believed to have congenital palsy by history and clinical examination were found to have lax tendons. No patient with acquired unilateral palsy showed similar tendon laxity. CONCLUSION: These findings have significant implications regarding the diagnosis and possible cause of congenital superior oblique palsy as well as implications for surgical management.