An Update on Constraint Therapy in Children with Hemiplegia
Constraint therapy aims to improve the hand and arm use of children with hemiplegia. It involves physical constraint of the uninvolved or less affected arm to increase the use of the more involved or affected arm. This type of therapy has been successful in children with hemiplegia (or asymmetric upper extremity motor difficulties). Constraint therapy is also sometimes referred to as constraint induced movement therapy (CIMT) and constraint induced therapy (CIT) in the literature. Constraint therapy has been paired with intensive behavioural training or with less intensive practice involving traditional occupational therapy approaches.
What do we know about the use of constraint therapy in children?
To date, 12 studies have been published on constraint therapy in children. The American Academy of Cerebral Palsy and Developmental Medicine (AACPDM) uses a classification system from "I" to "V" to rate studies and to examine the evidence in support of a treatment intervention In Table 1 we have included those studies with five or more children that report outcomes. Each of the studies has been rated according to its strength of evidence with a score of "I" representing the strongest evidence and "V" being the weakest. A level "I" study is a large trial where subjects are randomized (similar to flipping a coin) to a treatment and a control group. A level "II" study is a small randomized trial with uncertain results. A level "III" study is a prospective study of a treatment and a control group but the assignment to the group is not randomized. A level "IV" study consists of a comparison between the outcomes of a treatment group compared to a historical control group, and a level "V" study is a case series without a control group.
The evidence to support a treatment intervention can also be given a grade with "A" being the highest (evidence supported by one or more level "I" studies) and "C" being the lowest (supported by level "III", "IV" and "V" studies). The overall grade for the use of constraint therapy in children with hemiplegia is graded at an "A" level with three level "I" studies showing positive results.
The origin of constraint therapy
Constraint therapy originated from Taub's early work with monkeys (Taub, 1980). Taub studied monkeys where one of the forelimbs was surgically injured and the other forelimb was left intact. He observed that the monkeys would initially try to use the affected limb but were unsuccessful and resorted to using the intact limb. Later the intact limb was restrained for three days and the monkeys used the affected limb. After he removed the restraint he found that the monkeys continued to use the affected limb. He hypothesized that disuse of the affected or involved limb is learned and with mass practice the monkeys were able to learn to use the affected limb again. The first studies of constraint therapy in humans were conducted in adults post-stroke (Ostendorf & Wolf, 1981; Wolf, Lecraw, Barton, & Jann, 1989). Taub later paired restraint of the involved limb in adults post-stroke with structured intensive practice involving behavioural techniques and defined this as constraint induced movement therapy (CIMT) (Taub, Uswatte, & Pidikiti, 1999). Constraint therapy in adults post-stroke has shown improvements in motor control in the affected arm.
How does constraint therapy work?
It has long been believed that the brains of children are felt to have more capability than adults for cortical reorganization and it has been suggested that children with asymmetric upper extremity motor control may also benefit from constraint therapy (Johnston, 2001).
In constraint therapy the child's less affected or uninvolved arm is placed in a restraint and is constrained anywhere from 2 to 4 weeks except in Eliasson's study where the children wore a temporary restraint over a period of two months (Eliasson, 2003). The types of restraints used have varied in the literature and have included slings, mitts, splints, and casts. The restraint may be applied anywhere from a few hours up to twenty-four hours of a child's day. During the period of constraint the child may receive therapy to facilitate practice using the affected arm from as little as one hour to as much as six hours daily per week. The type of therapy provided also varies. The practice may be formal and structured involving behavioural shaping strategies or be less formal and involve traditional occupational therapy. The family and the child may also be encouraged to use the restraint at home to integrate the affected or involved arm into the child and family's routine daily activities.
What are the benefits?
All the studies have reported some positive change in arm and/or hand function in children with asymmetric upper extremity motor control and these are outlined in Table 1
The benefits include:
- improved quality of hand use;
- new motor movements of the affected arm or hand;
- more spontaneous use of the affected arm or hand;
- improved hand function such as fine motor and grasp.
Anecdotes from parents have reported that their child is able to participate in more daily activities. Studies are reporting maintenance of some results six months following constraint therapy.
Are there risks?
Associated risks reported in the literature with constraining the child's uninvolved or unaffected arm and hand include:
- some temporary loss of independence, as the child will be using the affected arm to complete daily activities;
- possible increase in frustration;
- possible increase in risk of falls and loss of balance as the restraint may affect posture and inability to protect themselves in a fall;
- possible increase risk of injury to the involved arm and hand because the child is using the affected arm more but has decreased sensory awareness and motor control.
In some children if a cast was used there have been reports of mild stiffness of the uninvolved hand upon cast removal, but the stiffness usually resolves in a couple of days. The impact of constraining the uninvolved arm in a young child is also unknown.
What don't we know about constraint therapy?
As the methods for constraint therapy differ in the literature, it is difficult to draw conclusions about:
- which types of children would most benefit from constraint therapy;
- if children with different levels of upper extremity impairment respond differently;
- which type(s) of restraint would be most effective;
- what is the optimal duration of constraint therapy;
- is there an optimal time during a child's development that constraint therapy would be most effective;
- how much therapy is needed to facilitate practice of the affected arm that would most improve motor control and upper extremity function;
- how long should we wait before we repeat constraint therapy;
- what are the long term effects of constraint therapy.
Constraint therapy has recently been used in children with hemiplegia and the evidence to date is promising with three randomized controlled trials showing positive results. The remaining nine studies are Levels "III" to "V" but all report at least some positive changes in arm function of children with some results lasting six months. Overall the evidence for the use of constraint therapy in children is graded at an "A" level. However, ongoing investigation is required to continue to evaluate the effectiveness of constraint therapy in children and answer some of the questions raised above.
Update written by:
Sophie Lam-Damji, OT Reg. (Ont.), Occupational Therapist Child Development Program, Bloorview Kids Rehab; Lecturer (Status-Only), Department of Occupational Science and Occupational Therapy, University of Toronto.
Darcy L. Fehlings, MD MSc FRCP(C), Physician Director, Child Development Program, Bloorview Kids Rehab; Division of Developmental Paediatrics, Associate Professor of Paediatrics, University of Toronto.
Want to know more? Contact:
Child Development Program
Bloorview Kids Rehab
150 Kigour Road
Toronto ON. , M4G 1R8
416-425-6220 ext. 3079