A STUDY OF FUNCTIONAL SPINAL MOTION IN WOMEN AFTER INSTRUMENTATION AND FUSION FOR DEFORMITY OR TRAUMA

Study Design. Photographs were used to measure the residual spine moti on in 71 women who had undergone spine fusion and instrumentation for spinal deformity or trauma. Objectives. To accurately define the abili ty of the patient to flex, extend, and bend to the right and left, thu s providing the surgeon some accurate information rather than speculat ion regarding spinal motion. Methods. The 71 patients had undergone sp ine fusion with instrumentation for scoliosis, kyphosis, or spine trau ma. The average age of the patient at surgery was 22 years, ranging fr om 11 years to 62 years. The average time since surgery was 6 years, r anging from 1 year to 32 years. Each patient had six views photographe d: flexion, extension, right and left side bending from the front, and right and left side bending from the back. Each photograph was measur ed independently by two research assistants. A total of 852 photograph s were analyzed. Results. The average degree of right side bending was 22 degrees, that of left side bending was 23 degrees, that of flexion was 111 degrees, and that of extension was 30 degrees. For the 59 pat ients who underwent fusion of seven levels or more and who were fused down to T12, L1, L2, L3, or L4, there was no correlation of the range of motion with the lowermost level of fusion, except in patients with fusion to L4 who had significantly less motion. Flexion was primarily a function of hamstring tightness and was best in those who exercised regularly (aerobics, gymnastics, ballet), regardless of the number of levels fused or the lowermost level of fusion. Conclusion. Typical spi ne fusions for deformity produce a moderate loss of functional motion, except in patients who undergo fusion to L4 who lose much more. The t echnique of analysis was found to be highly accurate and reproducible.