Long-term Follow-up of Myelomeningocele Patients: Factors That Can Affect Their Walking Ability.

BACKGROUND: Patients with spina bifida are living longer and more productive lives; however, many continue to experience functional limitations in adulthood. This study evaluated long-term functional progression and ambulatory status using the combined Myelomeningocele Functional Classification (MMFC) and Functional Mobility Scale (FMS), and examined factors associated with long-term changes.

METHODS: A retrospective review at a tertiary care rehabilitation center identified 168 patients with spina bifida. MMFC and FMS classifications were recorded at initial and final visits. A subgroup of ambulatory patients who underwent 3D-gait analysis was analyzed to assess the relationship between MMFC, body mass index (BMI), and functional speed (FS) using multiple linear regression.

RESULTS: The average follow-up was 15±10.31 years. The mean age at final follow-up was 20 years (range, 5 to 52), with 52% of patients being male. Fifty-two percent of patients were ≥18 years of age at final follow-up. Within the MMFC1 cohort, 48% used wheelchair mobility (FMS 1,1,1) at initial presentation; this increased to 80% at final follow-up. Eighty percent of the MMFC2 patients were able to complete the 50-yard walk test at initial classification, whereas only 60% were able to complete it at final follow-up. Within the MMFC3 cohort, there was a decline in patients requiring no external support (FMS 6,6,6) from 90% to 78%. All MMFC4 patients maintained an FMS of 6,6,6. A statistically significant relationship was found between functional speed (FS) and MMFC (with MMFC4 faster than MMFC3 and MMFC2) (P=0.01414).

CONCLUSIONS: Long-term follow-up demonstrates that functional classification may decline over time in MMFC1 to 3 cohorts, whereas MMFC4 remains stable. In addition, within individual cohorts (MMFC1 to 3), there was also a decline in FMS and functional walk testing. A positive and statistically significant relationship was observed between gait analysis FS and MMFC, and a negative and statistically significant relationship was observed between BMI and MMFC. The combined use of MMFC and FMS provides a structured framework for longitudinal functional assessment in patients with spina bifida.

LEVEL OF EVIDENCE: Level III.