Late diagnosis of spinal dural arteriovenous fistulas resulting in severe lower-extremity weakness: a case series.

Background Context: Spinal dural arteriovenous fistula (SDAVF) is a slow-flow extramedullary vascular lesion affecting primarily the lower thoracic and lumbar spine. The clinical sequela of these vascular changes is progressive myelopathy and severe lower-extremity weakness. Although surgical or embolic treatment of SDAVFs has improved significantly in the last years, the ambiguity of the symptoms may complicate and delay the diagnosis. The influence of the postponed diagnosis on the functional outcome of patients with SDAVF is unknown.

Purpose: To describe a case series of patients with SDAVF that illustrates that delayed diagnosis leads to grave neurologic and functional prognosis.

Study Design: A case series.

Methods: We present a series of seven patients, treated in a tertiary university rehabilitation center over 20 years. Clinical, radiologic, and functional outcomes were evaluated by retrospective chart review. Neurologic and functional evaluation at the end of rehabilitation was evaluated with the lower extremities motor score and the Aminoff-Logue scale, respectively.

Results: All our patients were men with a mean age of 60.3±16 years (30-72 years), mean time until the diagnosis of SDAVF was 302.8±239 days (60-730 days), and mean overall length of stay in acute department and rehabilitation unit was 88.6±34 days (46-149 days). At the end of rehabilitation period, four patients remained at wheelchair level with an Aminoff-Logue scale grading of five whereas other functional scales showed also low levels of recovery.

Conclusions: Our series showed that the potential for functional ambulation was poor despite prolonged rehabilitation treatment in late diagnosis SDAVF. Awareness of the early symptoms of SDAVF and immediate intervention may help reduce impairment in such patients.