Abstract
Introduction The influence of timing of surgery on functional outcomes following spinal cord injury remains controversial. Animal studies suggest that the rate, degree, and duration of cord compression are the principal determinants of spinal cord injury (SCI) severity and prognosis for recovery. Delamarter et al, (J Bone Joint Surg Am 1995) have shown that when experimental cord compression in dogs is relieved within 1 hour, full motor recovery can be achieved. It is suggested by some clinically based research that definitive surgical treatment for unstable injuries results in fewer sequelae than prolonged immobilization and allows more rapid entry into rehabilitation. It is however the timing of this surgery which remains controversial. It has been suggested that early surgical management promotes neurological recovery by limiting secondary damage caused by inflammation, oedema, ischemia and instability. To date few studies have found a link between neurological recovery and timing of surgery (Fehlings, et al; Spine 2001).
Methods Data was gathered retrospectively by chart review of patients referred to the Princess Alexandra hospital with spinal cord injury. Patients were age matched into high and low velocity groups. This data was studied to assess the effects of energy of injury and timing of surgical intervention on neurological outcome. Patients either had anterior, posterior, or combined surgery, external immobilization or traction depending on the preference of the treating surgeon.
Results A cohort of 43 patients all of whom had spinal cord injury was retrospectively studied. Of these, 21 had a high energy injury (eg. MVA) and 21 had a low energy injury (eg. rugby). 28 had anterior stabilization 7 had traction, 4 had external immobilization 2 had a combined anterior / posterior fixation and 1 had posterior stabilization. The data suggest that the prognosis for recovery following a spinal cord injury is unrelated to the energy involved. The low energy group improved on average 0.6 ASIA grades (SEM 0.16) while the high energy improved 0.7 ASIA grades (SEM 0.17). The timing of definitive intervention for patients with incomplete cord lesions was shown to significantly (p=0.029) effect ultimate functional outcomes. Those with early (within 8hrs) intervention improved an average of 1.4 ASIA grades (SEM 0.21) and those with late intervention improved 0.6 ASIA grades (SEM 0.19). This effect was present in both high and low energy injury groups.
Discussion The timing of definitive intervention for spinal cord injury is still controversial. However there is Class II evidence that early surgery can be done safely in a patient with spinal cord injury (Fehlings, et al; Spine 2001). The findings from this retrospective study suggest that early surgical intervention may improve neurological recovery.
The abstracts were prepared by Professor Bruce McPhee. Correspondence should be addressed to him at Orthopaedics Division, The University of Queensland, Clinical Sciences Building, Royal Brisbane & Women’s Hospital, Herston, Qld, Australia