Late follow-up of 190 patients with dorso-lumbar spinal fractures treated by transpedicular screw and plates

ABSTRACT

Between 1989 and 1995, at the Department of Orthopaedic Surgery, Assiut University Hospital, 190 patients with thoracolumbar frctures underwent surgical treatment. There were 115 males and 75 females; the average age was 27.7 years [range, 17 to 65 years]. The affected level was D-10 in 16 patients [8.4%]; D-11 in 13 [6.8%]; D-12 in 60 [31.5%]; L1 in 50 [26.3%]; L2 in 28 [14.7] L3 in 23 [12.1%]. According to the Magert and Harms classification [1988], 70 patients [36.8%] had flexion compression fractures, 89 [46.8%] had flexion distraction fractures and 31 [16.4%] had torsional injury. On admission and according to Frankel classification 55 patients [28.9%] were grade A, 30 [15.9%] grade B, 45 [23.7%] grade C, 40 [2 1%] grade D and 20 patients [10.5%] grade E. The mean operative time totaled 2 hours. Spinal plates were used in 45 patients [23.8%] and NDCP in 145 patients [76.2%]. Decompression was carried out in 125 patients [65.8%] with neurological compromise. In the earlier cases, 22 [11.6%] patients underwent fusion in combination with instrumentation. 86 patients had their implants removed for different indications. The metal was removed in 34 patients after screw failure, 6 with severe back pain without loosening of the implant and in 46 patients according to their demand. At the final follow-up which ranged from 3 to 7 years [average 4.5 years], fifty patients [26.3%] with incomplete paraplegia returned to normal; no improvement occured in patients with complete paraplegia. No neurological deterioration was reported. Compared to the preoperative status, our follow-up examinations demonstrated improvement in the neurology and function. 50 patients [26.3%] with incomplete paraplegia showed neurological improvement by one or two grades at least. The back pain was excellent and good in 79%; the range of motion was excellent and good in 85%. The radiographic assessment in the lateral plan [Cobb technique] demonstrated a significant [P < 0.001] mean restoration from an initial angle of 23.5° to 7° with gradual loss of reduction of about 2° after metal removal. There was a mean gain of regional kyphotic angle 16.3°. The mean gain of the vertebral height was 46% and the mean loss was 9%. The mean gain of the retropulsion was 8mm and the mean loss was one mm only. The preoperative wedge angle of the verebral body correlated significantly with the postoprative loss of reduction. The implant removal did not lead to increase in the range of back motion. It did not change the neurological state or lead to improvement in the back pain except in those with pain due to implant failure. The complications related to the instrumentation were screw malposition in 15 patients [7.8%], screw loosening or breakage in 34 patients [17.9%], with no metal breakage