Evaluation and Conservative Management of Spondylolisthesis

Plain x-rays of the lumbar spine are not helpful in diagnosing most known causes of low back pain but can reveal structural changes such as disc space narrowing, scoliosis, lumbarization or sacralization, spondylolysis, and spondylolisthesis. Spondylolisthesis is defined as the forward displacement of one vertebrae upon another, usually at the L5-S1 level, but also occurring at L4-5. For spondylolisthesis to occur there must be an anatomical change in the structures which normally resist the anterior displacement of one vertebrae upon the other. Forward slippage is resisted by the bony block of the posterior facets, by the intact neural arch and pedicle, by normal bone plasticity preventing stretch of the pedicle, and by the intervertebral disc bonding the vertebral bodies together.¹ The degree of vertebral body anterior displacement is rated from 1–4 depending upon the severity of the slip.² Five major categories have been proposed for the classification of spondylolisthesis.³ Clinically, the type most often seen is a defect in the pars interarticularis of L5 with resultant slippage of L5 on S1. This is known as isthmic spondylolisthesis. The other commonly seen type of spondylolisthesis is degenerative, arising from the remodeling of the facet joints so that bony opposition to resist anterior displacement of one vertebrae upon another no longer exists. Degenerative spondylolisthesis most commonly occurs at the L4-5 level in women over the age of 40. Surgical intervention for treatment of spondylolisthesis is well documented,^4–6 but literature regarding conservative management is scarce. The purpose of this article is to present an evaluation and treatment approach which has been found by the author to be clinically effective for patients presenting with symptomatic grade I or II isthmic or degenerative spondylolisthesis.

Documented conservative treatment for spondylolisthesis includes instruction in exercise and body mechanics, the use of back supports including antilordotic orthoses, and job modifications. Magora⁷ recommends strengthening of the abdominals and paraspinal muscles, especially in the thoracic area, as well as occupational modifications and instruction in body mechanics, deep-heat therapy, avoidance of maximal forward flexion of the lumbar spine, and in severe cases, bed rest. He recommends three to four months as the minimal trial period for conservative treatment. Gramse et al.⁸ and Sinaki et al.⁹ compared two types of exercise programs over a three-year period for patients with symptomatic spondylolisthesis. Patients were divided into two groups with one group performing a flexion routine consisting of abdominal curl-ups, posterior pelvic tilts, and seated trunk flexion; a second group was instructed in extensor strengthening exercises performed in prone lying. The authors found that patients treated with the flexion exercise program were less likely to require the use of back supports, require job modification, or limit their activities because of pain. At three-year follow-up only 19% of the flexion group had moderate or severe pain compared to 67% of the patients in the extension group.⁹ Gramse et al.⁸ and Sinaki et al.⁹ did not describe how they determined that the spondylolisthesis was indeed symptomatic. Bell et al.¹⁰ reported 100% success with the use of an antilordotic orthosis in 28 children (mean age 11.4 years) with grade I and grade II isthmic spondylolisthesis. Other authors have been less enthusiastic about the use of corsets and braces.^7,11