Walking ability and predictors of performance on the 6‐minute walk test in adults with spastic cerebral palsy

Abstract

To describe walking ability and identify factors predicting walking capacity in adults with spastic cerebral palsy (CP) assessed with the 6-minute walk test (6MWT). A cross-sectional clinical study as part of the recruitment process for a randomized controlled trial on the effects of botulinum toxin A. Data analysed were the 6MWT, Timed Up and Go (TUG) test, Borg Scale, spasticity, muscle strength, popliteal angle, pain, fatigue, type of CP, foot deformity, Gross Motor Function Classification System (GMFCS) levels, Functional Mobility Scale (FMS) scores, a gait questionnaire, interview, and demographic data. In total, 126 persons were included (53 males, 73 females; mean age 39 y [SD 12 y]; 59 with unilateral and 67 with bilateral spastic CP; GMFCS level I, n=12; level II, n=94; level III, n=20). Mean distance on the 6MWT was 485 m (SD 95 m) with FMS scores reflecting independent walking performance in daily life. Multiple regression analysis identified sex, type of CP, popliteal angle, pain, and TUG values as significant predictors, with TUG values as the strongest predictor (standardized regression coefficient=-0.57, p<0.001). Our results demonstrate that 39% of the participants had declined one GMFCS level from adolescence to their present age, and that the TUG was the strongest predictor for the 6MWT. This implicates the importance of focusing specifically on the different elements of functional mobility in further studies.