Effects of stretching and heat treatment on hamstring extensibility in children with severe mental retardation and hypertonia.
OBJECTIVE
To examine the effect of heat and duration of stretching on the extensibility of hamstring muscles and their electromyographic responses to passive stretch in children with hypertonia and severe mental retardation.


METHODS
Randomized cross-over trial.


METHODS
Developmental disability unit in a local hospital.


METHODS
Twenty-nine subjects (9 females) with ages ranged from 4 to 13 years with spastic and/or dystonic hypertonia and hamstring tightness.


METHODS
Subjects received four treatment sessions in random order with each consisting of five repetitions of stretching: (A) 10-second stretching, (B) 30-second stretching, (C) hot pack followed by 10-second stretching, and (D) hot pack followed by 30-second stretching. Each treatment session comprised five repetitions of stretch and successive treatments were separated by at least 24 hours.


METHODS
The distance between greater trochanter and lateral malleolus and hamstring electromyographic (EMG) activity during passive knee extension stretching.


RESULTS
Two-way ANOVA showed a larger increase in hamstring extensibility in conditions C and D (1.3 +/- 1.1 cm) than conditions A and B (0.7 +/- 0.9 cm) (P<0.001). For the EMG recordings, conditions B and D (-25.1 +/- 58.4 microV) had greater decrease than conditions A and C (-3.5 +/- 36.6 microV) (P= 0.039).


CONCLUSIONS
Heat application to the hamstrings before stretching could result in greater increase in extensibility than stretching alone in children with hypertonia and severe mental retardation. Stretching could promote relaxation of the hamstring muscles regardless of prior heat treatment. Stretching sustained for 30 seconds led to greater relaxation than that for 10 seconds.
Lee
Glory Ps
GP
Caritas Jockey Club Lok Yan School, Hong Kong.
Ng
Gabriel Yf
GY
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D018592:Cross-Over Studies; D004421:Dystonia / Q000534:rehabilitation; D005260:Female; D006358:Hot Temperature / Q000627:therapeutic use*; D006801:Humans; D008607:Intellectual Disability / Q000534:rehabilitation*; D007866:Leg; D008297:Male; D009122:Muscle Hypertonia / Q000534:rehabilitation*; D009128:Muscle Spasticity / Q000534:rehabilitation; D052580:Muscle Stretching Exercises