Creatine supplementation for weak muscles in persons with chronic tetraplegia: a randomized double-blind placebo-controlled crossover trial.
OBJECTIVE
Creatine supplementation improves muscle strength in some patient populations with neurologic disorders. The purpose of this study was to determine whether creatine supplementation improves muscle strength and endurance in weak upper limb muscles in persons with tetraplegia, and whether it improves function.


METHODS
Outpatients with tetraplegia and mild wrist extensor weakness were randomized to receive either creatine or placebo in a double-blind crossover design. During creatine supplementation, participants were loaded with 10 g orally twice per day for 6 days, then maintained on 5 g daily until undergoing testing. Main outcome measures, performed at baseline, after placebo, and after creatine supplementation, included maximal voluntary wrist extensor isometric contraction strength (MVC), endurance times for 5 submaximal wrist extensor contractions, and the Grasp and Release Test for hand function.


RESULTS
Eight individuals (7 men, 1 woman) with tetraplegia met inclusion criteria and completed all study phases. The mean age of participants was 48 years, and 7 of 8 had C6 motor level injuries. There were no significant differences in MVC, endurance times, or hand function for creatine vs placebo.


CONCLUSIONS
Creatine does not improve MVC and endurance of weak wrist extensors and does not improve hand function in individuals with tetraplegia.
Kendall
Richard W
RW
Division of Physical Medicine and Rehabilitation, University of Utah, Salt Lake City, Utah, USA.
Jacquemin
Géraldine
G
Frost
Randee
R
Burns
Stephen P
SP
D002574:Cervical Vertebrae; D002908:Chronic Disease; D003401:Creatine / Q000627:therapeutic use*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D006225:Hand; D018737:Hand Strength; D006801:Humans; D007537:Isometric Contraction / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D018908:Muscle Weakness / Q000188:drug therapy* / Q000209:etiology* / Q000503:physiopathology; D018482:Muscle, Skeletal / Q000503:physiopathology; D010807:Physical Endurance; D011782:Quadriplegia / Q000150:complications* / Q000209:etiology; D013119:Spinal Cord Injuries / Q000150:complications; D017211:Treatment Failure; D014953:Wrist
D003401:Creatine