Chronic Low-Back Pain and Its Response to Custom-Made Foot Orthoses.

Dananberg H J, Guiliano M (Private practice, Bedford, NH), J Am Podiatr Med Assoc. 1999;89:109-117.

This study monitored the subjective reports of patients with low back pain that described their level of functional disability before and after receiving a custom-made foot orthosis. Thirty-two subjects entered the study. All of them had a long history of back pain and were considered to be reaching the medical endpoint for their conditions; they had all been treated unsuccessfully with several standard modalities for low back pain, including spinal manipulation, physical therapy, therapeutic injections, and, in some cases, surgery.

Mean pain scores were calculated from the Quebec Back Pain Disability Scale questionnaire prior to treatment, after wearing a custom orthosis for at least 1 month, and after wearing the orthosis for at least 6 months. The pain scores were calculated for 2 time periods: the initial phase (representing pretreatment to at least 1 month posttreatment) and the follow-up phase (representing the difference between the scores at pretreatment and assessment and those at least 6 months after the orthoses were dispensed). Thirty-two subjects completed the first phase, and 23 subjects completed both phases. The subjects were evaluated for objective and subjective gait disturbances, and they underwent a pediatric biomechanical foot evaluation. Particular attention was paid to sagittal plane movement at the ankle and first metatarsophalangeal joint.

Treatment consisted of customizing an initial test orthosis based on gait analysis as well as range-of-motion exercises for the metatarsophalangeal joint, ankle, and fibular head when appropriate. Modifications to the temporary orthosis were made until the researchers were satisfied with its ability to maximally improve gait mechanics. Permanent orthoses, which were modeled on the corrections made to the temporary devices, were then dispensed.

Results of the self-reported functional pain scale revealed that 84% of the patients experienced improvement in their symptoms. The subjects in the follow-up phase experienced a statistically significant improvement in alleviation of pain after an average of 13.8 months of orthotic treatment.

The authors discussed in detail the biomechanical and pathomechanical consequences of gait disturbances that are secondary to functional loss of sagittal plane motion at the ankle and first metatarsophalangeal joint. They emphasized the importance of the position of hip extension prior to the pre-swing phase and the subsequent increased demands on the iliopsoas muscle and compensatory lateral trunk flexion. They believed that the study's findings may provide a new method to manage patients with chronic low back pain.

Robert Tank, PT, ATC Orthopaedic Associates Inc Evansville, Ind