Some people develop a curvature of their lower spine as they become older. They did not have this in their earlier years, but develop this curve as they age. Their spine appears crooked from the back, and one shoulder droops when compared to the other one. This condition is known as degenerative lumbar scoliosis.
Along with the scoliosis (which is sideways or coronal curvature in the spine), many patients also develop a straightening of their lumbar spine. Normally, the lower back has a swayback-type appearance, in which the lower back arches backwards (lumbar lordosis). This is the opposite of the hunchback seen in the upper back region (thoracic kyphosis). As many people age, they lose the natural lumbar lordosis and - as a result - they walk with a forward bending appearance (sagittal imbalance).
Both of these alignment abnormalities have a common underlying cause. These problems are due to uneven wearing out of the shock absorbers or discs in between the vertebra of the lower back. As a result of right side of the disc wearing out faster than the left side and the front of the disc wearing out faster than the back part of the disc, the spine develops an abnormal alignment and appearance in aging patients.
This condition - degenerative lumbar deformity - can be easily diagnosed on physical examination and with xrays. An MRI can demonstrate the asymmetric wear or tear present at the disc levels as well as demonstrate if there is any compression of the nerves in the region of the deformity. If an MRI cannot be obtained for medical reasons, a CT scan will also demonstrate the disc degeneration and appoximate the degree of narrowing around the nerves.
The treatment of this condition requires significant surgical risks and thus is largely avoided given the age and medical frailty of many of these patients. Physical therapy and oral medications can help decrease some of the lower back pain and stiffness that these patients commonly feel. Injections can be used, especially if the patient develops sciatica-type pain from compression of the nerves from the deformity.
Surgical intervention is a last resort option, only used for when the patient's back pain is not responding to any other treatment, the patient's leg pain/weakness are worsening, and/or the patient is developing bowel/bladder problems. Due to the extent of the deformity, multiple levels of the spine often need to be treated and thus an extensive surgery has traditionally been the only option. Given the length of surgery, the medical frailty of these patients, the extent of blood loss, the osteoporotic bones, and the risk of infection, these patients have a much higher risk of a complication during surgery and for the first year after surgery.
New techniques are emerging that is making surgical correction of the spine easier and less risky. These minimally invasive approaches can be used to correct the deformity by removing the discs and fusing the spine. The traditional 'open' surgical procedure often takes several hours, involves significant blood loss, and has high risk of infection; all of these are not well tolerated in a medically fragile patient. It may become more common in the near future to treat these patients with the minimally invasive techniques in order to minimize medical and surgical complications.
Please discuss any further questions about your specific situation with a fellowship-trained orthopedic spine surgeon.