Spinal Range of Motion, Muscle Strength and Back Pain at Least 20 Years After Fusion or Brace Treatment for Adolescent Idiopathic Scoliosis - A Follow-Up With a Non-Scoliotic Control Group

Introduction: A consecutive series of patients with adolescent idiopathic scoliosis (AIS), treated between 1968 and 1977 before 21 years of age, either with distraction and fusion using Harrington rods (ST, n=156; 145 females and 11 males) or with brace (BT, n=127; 122 females and 5 males) were followed at least twenty years after completion of the treatment.

Purpose: To determine the long term outcome in terms of muscle strength and spinal mobility and its possible correlations to present back pain in patients surgically or brace treated for AIS.

Methods: One hundred and thirty-five (87%) of ST and 102 (80 %) of BT patients underwent a complete examination by unbiased observers incl. evaluation of muscle strength and spinal mobility, curve size (Cobb method) in full standing frontal radiographs, validated questionnaires in terms of general and diseasespecific quality of life aspects as well as present back and pain symptoms. An age- and sex-matched control group of 100 persons was randomly selected and subjected to the same examinations.

Results: The mean follow-up time was 23 years for ST group and 22 years for BT group. Curve size (major curve) was mean 36 degrees (SD 10, 14-66) for ST and 38 degrees (SD 15, 5-71) for BT patients. Significantly more patients (78% of ST and 76% of BT) complained of back pain during the last year in comparison to the control group (58%, p=0.0004 and p=0.0012 resp.). Lumbar pain was significantly more frequent among the patients than the controls (65% for ST and 67% for BT vs 47%).

For both BT and ST patients, lumbar spine motion was significantly decreased compared to controls, a reduction with 37% for BT and 61% for ST. Muscle strength of both spinal and abdominal muscles was also significantly decreased, for ST with 41% and 31% and for BT with 29% and 30% respectively, compared to controls. ST patients also had reduced thoracic as well as cervical spine motion. More BT patients with reduced lumbar spinal mobility experienced lumbar back pain and also had more pain in general (Total Body Area Score) compared to controls. Except for this, no correlation could be found between occurrence of back pain (cervical, thoracic or lumbar) and spinal or abdominal muscle strength or degree of thoracic or lumbar spine motion for either group.

Discussion and Conclusion: For both brace treated and surgically treated AIS patients, spine mobility and muscle strength were reduced more than twenty years after completed treatment. For brace treated patients a correlation could be found between reduced lumbar spinal mobility and lumbar and general pain. For the fused AIS patients, however, no correlations could be found between muscle strength or spinal mobility and back pain.