Laminar and arch fractures with dural tear and nerve root entrapment in patients operated upon for thoracic and lumbar spine injuries.

OBJECTIVE

To determine the neurological outcome in patients with laminar fractures associated with dural tears and nerve root entrapment, operated upon for thoracic and lumbar spine injuries.

PATIENT POPULATION: Out of 103 patients operated upon consecutively for thoracic and lumbar spine injuries during the period 1990 to 1994 inclusive, 24 (23.3%) patients had laminar fractures out of whom 3 (2.9%) had an associated dural tear and an other 17 (16.5% or 70.8% of the total patients with laminar fractures) had an associated dural tear and nerve root entrapment.

RESULTS

Twelve (70.5%) patients had injury at the thoraculumbar junction, 13 (76.5%) had Magerl's type A3 or above, 10 (58.8%) had a kyphotic angle deformity greater than 5 degrees. Seven (41.1%) had their spinal canal's sagittal diameter reduced by at least 50% and two had dislocations. Nine (52.9%) had initial neurological deficits. Four (50%) out of 8 patients with no initial neurological deficits (Frankel E) worsened to Frankel D. However, one patient among the 3 with initial Frankel A improved to Frankel C while both patients with initial Frankel C usefully improved to final Frankel grades D and E respectively. Two of the four patients with initial Frankel D improved to Frankel E, the other 2 remaining unchanged. All in all five patients neurological status improved, 4 worsened and 8 remained unchanged after neurosurgical treatment.

CONCLUSIONS

Vertical laminar fractures with dural tears and nerve root entrapment represent a special group of thoracic and lumbar spine injuries that carry a poor prognosis. However, special operative precautions lead to significant improvement in some of them although a majority remain unchanged or even worsened.