Twenty-four patients diagnosed with acute myelopathy, hospitalised in the spinal cord injury service, received LMWH prophylaxis (12 male; mean age:48.5 years). This group had 4 patients with transverse myelitis, 5 with spinal stenosis, 11 with traumatic injury and 4 with neoplasms. The patients treated with LMWH were matched by diagnosis (11 trauma, 5 degenerative, 4 transverse myelitis and 4 tumours) with patients who received LDUH (13 male; mean age:50.4 years). Power calculations to determine the sample size were not undertaken.