Interventions to Reduce Spasticity and Improve Function in People With Chronic Incomplete Spinal Cord Injury: Distinctions Revealed by Different Analytical Methods.
BACKGROUND
Spinal cord injury (SCI) results in impaired function, and ankle joint spasticity is a common secondary complication. Different interventions have been trialed with variable results.


OBJECTIVE
We investigated the effects of pharmacological and physical (locomotor training) interventions on function in people living with incomplete motor function loss caused by SCI and used different analytical techniques to understand whether functional levels affect recovery with different interventions.


METHODS
Participants with an incomplete SCI were assigned to 3 groups: no intervention, Lokomat, or tizanidine. Outcome measures were the 10-m walk test, 6-minute walk test, and the Timed Up and Go. Participants were classified in 2 ways: (1) based on achieving an improvement above the minimally important difference (MID) and (2) using growth mixture modeling (GMM). Functional levels of participants who achieved the MID were compared and random coefficient regression (RCR) was used to assess recovery in GMM classes.


RESULTS
Overall, walking speed and endurance improved, with no difference between interventions. Only a small number of participants achieved the MID. Both MID and GMM-RCR analyses revealed that tizanidine improved endurance in high-functioning participants. GMM-RCR classification also showed that speed and mobility improved after locomotor training.


CONCLUSIONS
Improvements in function were achieved in a limited number of people with SCI. Using the MID and GMM techniques, differences in responses to interventions between high-and low-functioning participants could be identified. These techniques may, therefore, have potential to be used for characterizing therapeutic effects resulting from different interventions.
Northwestern University, Chicago, IL, USA lynsey.duffell@northwestern.edu mehdi@northwestern.edu.
Lynsey D
LD
Duffell
Rehabilitation Institute of Chicago, Chicago, IL, USA.
Geoffrey L
GL
Brown
Northwestern University, Chicago, IL, USA Rehabilitation Institute of Chicago, Chicago, IL, USA.
Mehdi M
MM
Mirbagheri
D000704:Analysis of Variance; D002574:Cervical Vertebrae; D002908:Chronic Disease; D003000:Clonidine / Q000031:analogs & derivatives / Q000627:therapeutic use; D003627:Data Interpretation, Statistical; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009125:Muscle Relaxants, Central / Q000627:therapeutic use; D009128:Muscle Spasticity / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology / Q000534:rehabilitation*; D010045:Outpatients; D012720:Severity of Illness Index; D013119:Spinal Cord Injuries / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology / Q000534:rehabilitation*; D013904:Thoracic Vertebrae; D016896:Treatment Outcome; D016138:Walking
D009125:Muscle Relaxants, Central; C023754:tizanidine; D003000:Clonidine
gait; spasticity; spinal cord injury