Sagittal Imbalance following Previous Surgery

History

The patient is a 70-year-old woman with rheumatoid arthritis who presents with a chief complaint of low back pain, fatigue with ambulation, and hunched posture. She has had two previous lumbar decompression and fusion procedures without instrumentation for spinal stenosis.

Examination

Marked truncal inclination is noted, no motor or sensory deficits to the extremities. Extremity deformities and joint stiffness is related to rheumatoid arthritis.

Prior Treatment

Pain management, bracing, physical therapy, and two surgeries.

Images

Long cassette standing films show significant sagittal plane imbalance and pelvic retroversion. Analysis with Surgimap Spine software shows an SVA in excess of 24 cm and pelvic tilt of 45-degrees. The lumbar lordosis is 19-degrees into kyphosis. (Fig. 1)

Figure 1.

Diagnosis

Flatback syndrome; fixed sagittal imbalance

Spino-pelvic malalignment; high PT/SVA

Rheumatoid arthritis (on methotrexate)

Post-laminectomy lumbar kyphosis

Selected Treatment

Surgimap Spine was applied to test several osteotomy combinations necessary for spino-pelvic realignment. Goals: SVA<55mm, PT<25.

All posterior realignment was performed using pedicle subtraction and facet osteotomies.

Figure 2.

Outcome

• The patient has had marked pain reduction; takes no pain medication.
• Her ambulation was increased to several blocks and she is very happy with her posture.
• Spino-pelvic realignment has been achieved.

Case Discussion

The case presented illustrates the complex nature of sagittal spinal balance. Forward flexed posture has been associated with increased low back pain and decreased functional outcomes. As illustrated in this rheumatoid patient status post multiple spinal procedures, correction of spinal deformity has to account for imbalance in multiple planes. While sagittal balance is demonstrated by the increase in SVA, coronal imbalance is also an issue. The patient demonstrates a shift in her center sacral line secondary to multi-level degenerative lumbar discs and pelvic obliquity due to leg length inequality.

Nonoperative treatment options have been exhausted. Surgical treatment options have significant potential complications and will test the most experienced spine surgeons. Decision-making in cases of this magnitude requires an outline of goals with a plan to achieve them. Primary objectives in this case would include pain reduction, improved gait and increased function. To best achieve these goals, correction of this patient's multi-planar deformity is the key.

Options outlined by the presenter should be considered with the goal of multi-planar deformity correction in mind. Posterior only correction (D) with iliac fixation and multiple osteotomies has proven effective for this reviewer. It would be difficult to achieve and maintain sagittal deformity correction with a short segment lumbar fusion alone. While anterior approaches have merit, they may also increase patient morbidity. Multiple posterior osteotomies with fixation can eliminate the requirement for anterior exposures. A single PSO would most likely not produce enough correction to achieve stated goals.

Reference:
Scoliosis Research Society (SRS) Webpage. Kyphosis and the Loss of Sagittal Balance with Aging. Retrieved December 14, 2008. http://www.srs.org/professionals/education/adult/kyphosis/sagittalbalance.php