History:At the time of the first encounter the patient was a 45-year-old lady who presented for consultation due to gradually increasing pain and spinal deformity. The patient stated that at the age of 12 she was diagnosed with idiopathic scoliosis. She was first treated by an exercise program and then placed for 9 months in a body cast. Due to progression of her scoliosis she underwent surgery at the age of 14. Unfortunately revision surgeries were necessary over the following years to treat increasing deformity and increasing discomfort. Her last surgery was performed to remove instrumentation in her spine that was felt to be a source of pain. Despite the numerous surgeries the patient noted increasing pain and a sensation of increasing deformity and poor balance. Her pain, which at first was mainly in the back began to involve leg pain and weakness.

Physical Examination:On examination the patient was noted to walk with a limp and in need of a cane. She required the assistance of another person to be transferred to an examination table. In the standing position the patient was significantly off-balance when seen from the front (trunk shift to the right) and from the side (trunk pitched forward with hips and knees flexed). The observation of the back showed overlapping scars, a right elevated shoulder and a marked deformity of the upper spine which was twisted to the left. Lower extremity examination revealed sensitivity to be decreased in the left leg with a decreased ankle jerk reflex on that side.

Radiographic Evaluation:Standing X-rays were difficult to obtain due to the deformity and patient ability to stand comfortably. A spinal fusion was noted to extend from the first thoracic vertebra to the 4th Lumbar vertebra with a typical Flatback and severe kypho-scoliosis (malalignment in both the frontal and sagittal planes). (figures 1,2,3,4)

The MRI of the lumbar spine showed a moderate stenosis at both the L4-L5 and L5-S1 levels. The review of a bone scan demonstrated areas of increased isotope uptake at the bottom of the spine consistent with osteoarthritis and in the middle of the fusion suggesting a pseudarthrosis.

Treatment Options:The treatment options available for complex cases of flatback generally range from analgesics, therapy and pain modalities to temporary bracing and possibly surgery. In this case pain management and therapy had already been pursued and judged as not acceptable in order to pursue an active life style. Surgical revision surgery is another option in the setting of marked spinal malalignment. The goals of such an intervention would be to ideally address the following: the pseudarthrosis, the malalignment in the frontal plane (ie. the trunk imbalance), the malalignment in the sagittal plane (the flatback). The exact surgical technique might include the following:

1. Repair of the pseudarthrosis with instrumentation / bone graft and surgical decompression to L5-S1. This may improve the focal pain from the pseudarthrosis and nerve irritation symptoms but does not address or correct the real problem of malalignment.

2. Performing osteotomies in both the thoracic and lumbar spines to correct the poor balance and re-fuse the spine to L4. Although this does not involve a direct decompression at L5-S1 such an approach is based upon the principle that fusion ending on a degenerated disc (if properly balanced) can offer advantages over a fusion extended to the sacrum. Motion at the L5-S1 level is preserved and nerve root symptoms related to subtle instability and traction can be reversed with a well aligned fusion.

3. Performing osteotomies in both the thoracic and lumbar spines to correct the poor balance and re-fuse the spine to L5. This approach, in the setting of markedly degenerated lumbar discs offers re-balancing the spine and ensuring lasting decompression of the affected nerves. Although motion is lost in the lowest spinal level the trade off is a stable and balanced spine.

DiscussionIn this complex case non-operative measures had not lead to any relief and the patient noted progressive disability over time with limitation in all activities. The patient wished to proceed with a surgical approach after careful review of all options and thorough discussions of risks and potential benefits. It was felt that in order to maximize the chances of lasting relief it would be crucial to obtain the following: solid fusion , alignment of the head above the pelvis in all planes, reduced magnitude of the deformity and decompression of the nerves at L4 -L5 and L5-S1 levels. Due to the markedly degenerated discs at L4-L5 and L5-S1 it was felt that realignment without extension of the fusion to the sacrum would only offer temporizing treatment due to the advanced degeneration at L5-S1. In some cases a shorter fusion can be very successful however, in this case this was felt to be a risky proposition.

Treatment and Results: As planned the patient was treated with anterior and posterior approaches to the spine. Multiple osteotomies were necessary to balance the spine and an extension of the fusion to the sacrum was performed. Following the posterior surgery a slight displacement of an interbody bone graft necessitated revision during the same hospitalization. The patient experienced an excellent recovery, her pain markedly decreased after surgery and was nearly completely resolved at one year follow up . Spinal alignment was restored, the fusion healed solidly and the patient has resumed her professional activities on a full time basis. (figures 5,6)

Flatback Medical Condition