Does grip strength reflect isokinetic muscle strength in lower limbs in patients with chronic inflammatory demyelinating polyneuropathy?

INTRODUCTION: Grip strength (GS) is a common measure of general muscle strength in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). However, it is important to investigate the correlation and responsiveness of GS compared with isokinetic muscle strength (IKS) and function of the lower limbs.

METHODS: Seventy patients with CIDP were evaluated with GS, IKS, and functional measures of the lower limbs. Reevaluation was performed after 2 and 10/12 weeks. Correlation and response analyses were performed.

RESULTS: GS correlated with IKS at the ankle (IKSankle ; maximum Spearman's rank-order correlation [RS ] = 0.58) and with walking performance (maximum RS  = -0.38). IKSankle was more responsive to detect change (standardized response mean [SRM] = 0.57) than GS (SRM = 0.27).

DISCUSSION: GS does not seem to be an appropriate surrogate measure of IKS and function of the lower limbs in patients with CIDP. Muscle Nerve, 2018.