Abstract
Introduction:
Scheuermann's kyphosis is a fixed round back deformity characterised by wedged vertebrae seen on radiograph. It is known patients presented with a negative sagittal balance before operation. Few studies investigated the outcome after operation, especially the change in the lumbar hyperlordosis.
Aim:
To investigate the change in sagittal profile after correction surgery.
Method:
This is a retrospective review of cases from 2001 to 2012. Our centre uses a posterior, four rod cantilever reduction technique for all Scheuermann's Kyphosis correction. 36 cases are identified. They include 24 males and 12 females with an average age of 20 and follow up of 27 months. First 8 cases used the stainless steel hybrid implants. The remaining 28 had titanium all pedicle screw system. All had intra-operative spinal cord monitoring.
Results:
The target of thoracic kyphosis correction is around the accepted upper end of normal limit (40°). The average thoracic kyphosis Cobb angle was 78.5°. The immediate post-op angle was 43.2° and at final follow up, 43.6°. The average lumbar lordosis changed from 65.7° pre-op to 48.8° post-op, which is now bigger than the thoracic kyphosis. The result is the transfer of average sagittal balance (C7 plumb line) from −2.2 cm to −3.5 cm, which remains posterior to the posterior corner of S1 after the surgery.
Discussion:
Surgery can improve the roundback deformity but not the overall sagittal profile. We have no explanation to this phenomenon. This could imply the pathology of Scheuermann's Kyphosis involves the whole spine, not just the wedging thoracic segment.
Conflict Of Interest Statement: No conflict of interest.
