Clinical Biofeedback Applications in Paediatric Rehabilitation

GILDA RUSSELL, B.A., M.ED. ELAINE SHARP, B.P.T., M.H.Sc., M.C.P.A. GEOFF ILES, PH.D., P.ENG.


Summary

Biofeedback research into the motor problems of the physically handicapped child has been ongoing at the Ontario Crippled Children's Centre, Toronto, for the past five years. Initial funding was from the Atkinson Charitable Foundation, Toronto, and present funding is by the Hospital for Sick Children Foundation, Toronto. The specific areas of study are head-position training and joint-position training for the knee. It is suggested that biofeedback training systems offer a significant new tool for rehabilitation practitioners, one which allows the patient to take an active part in his own rehabilitation process and provides an opportunity for him to improve at faster rates than traditional methods allow.

Introduction

The Rehabilitation Engineering Department at the Ontario Crippled Children's Centre has been involved in a biofeedback research programme for the past five years. Much of the initial investigation involved the design and construction of equipment. At present, the equipment is being used to conduct controlled study into the application of biofeedback treatment to the motor problems of the physically handicapped child.

Biofeedback can be defined as a procedure of monitoring the functioning of a particular response system of the body and presenting this information to the individual through a sensory receptor channel. The information may assist the individual to gain awareness of body processes and, in some cases, to gain volitional control over such processes. Phenomena such as heart rate1, blood pressure 5 , galvanic skin response 6 , and cerebral rhythms 3 have all been monitored and controlled with the use of feedback techniques.

In the treatment of the physically handicapped child, biofeedback techniques have been applied to impaired sensory-motor function 4,7 . Biofeedback for movement or response is provided to the child through an intact sensory receptor channel. Wooldridge and McLaurin9 suggested that the following prerequisites must be met for effective motor learning:

 

  1. specific goal-oriented activity
  2. self-initiated motor activity on the part of the child
  3. repetitive practice by the child
  4. immediate and precise feedback
  5. session-by-session success rate (accumulated performance feedback) made available to the child.

 

Present Investigations

The two main areas of concern are head-position training and joint-position training for the knee.

Head-Position Training

Study in this area has been ongoing over the years of the project. The early work with 12 cerebral-palsied children has been reported elsewhere 8 . In summary, all of the children responded to the training, with maintenance of learned ability being demonstrated with three of the children (Table 1). Since that time, equipment designs have been finalized: and a new study has been planned and started.

No.

Age

Motor
Age

Sex

CP Type

IQ

Hours of
Training

Actual
Time

No. of
Training
Activities

1-1
Training
Done

Feedback
Response
to
Training


1

6

2-5 mo.

M

Mixed-mainly
spastic

Low aver.

116 h. 50 min.

27 wks

6

X

Trained

2

3

3-4 mo.

M

Mixed-mainly
spastic

Aver. +

87 h. 50 min.

26 wks

5

X

Learned

3

10

5-6 mo.

M

Mixed-mainly
spastic

Aver.

53 h. 10 min.

23 wks

5

X

Learned

4

4

3-6 mo.

F

Spastic

?-Below Aver.

8 h. 5 min.

7 wks

3

 

Trained

5

4

1-2 mo.

F

Mixed

Aver

.

13 h.

7.5 wks

2

 

Sensative

6

5

2-4 mo.

M

Athetoid

Aver.

19 h. 55 min.

6.5 wks

4

 

Trained

7

6

3-6 mo.

F

Spastic

Low Aver.

34 h. 15 min.

10.5 wks

7

 

Trained

8

5

3-8 mo.

F

Spastic

Low Aver.

a)23 h. 10 min.
b)26 h. 15 min.

11 wks.
9 wks.

5

X

Learned

9

8

1-3 mo.

M

Athetoid

Low-?

a)22 h. 15 min.
b)10 h.

9 wks.
4 wks.

2

X

Trained

10

7

1-3 mo.

F

Mixed

Low Aver.

a)29 h. 40 min.
b)54 h. 5 min
c)71 h. 40 min.

10 wks.
10 wks.
8.5 wks.

6

X

Sensative

11

8

2-9 mo.

F

Mixed

Retarded

33 h. 35 min.

6

4

X

 

12

5

4-6 mo.

F

Spastic

Retarded

25 h. 5 min.

5

3

X

Trained

The study involves approximately 40 children and attempts to answer the following questions:

 

  1. Is biofeedback with the head-position trainer an effective mode for optimizing head-position ability in the cerebral-palsied child?
  2. Does biofeedback treatment produce significantly better training results than attention-placebo treatment, traditional treatment, or no treatment?
  3. Does generalization of optimal head-position ability occur when biofeedback has ceased?
  4. What are the roles of variables of age, sex, neurological deficit, intelligence, self-esteem, and locus of control?

 

Wheelchair control. One of the children in the original head-position training program was recently fitted with a head-control system modified to control a wheelchair. The child, a severely involved 10-year-old cerebral-palsied girl, is learning to drive the chair quite effectively although she was never able to control a conventional joy stick.

MK VIII Head-Position Trainer ( Figure 1 ). This is a biofeedback, mercury-switch device designed to provide and/or augment sensory information concerning spatial position of the head. It allows feedback-free movement to a pre-selected angle of 15, 25, or 35 degrees in posterior, anterior, and lateral directions from the vertical midline. When the child's head passes the pre-selected angle, he hears an audible signal; a move to the left or right causes a buzz to the respective ear; anterior or posterior movement causes buzzing in both ears. When the child moves his head within the degree setting, the signal will cease. The trainer has connections for a time/event counter to record the child's progress and a radio/cassette player which will operate with upright head position.

MKIV Time/Event counter ( Figure 2 ). This device is a portable, three-channel counter which has the facility to record and display frequency and duration of events and elapsed time. The frequency and duration-of-event channels are functionally interchangeable and can be disconnected for independent operation.

Joint-Position Training ( Figure 3 )

The equipment consists of

  1. A potentiometer to monitor the joint position.
  2. A Joint-Position Trainer (MARK IV) which provides an audible feedback to the child. This feedback is adjustable to the needs of the training and will also interconnect with foot switches if a specific part of the gait cycle is important in the training. Similar equipment was reported by Harris, et al. 4 , who developed a limb-position monitor for use on the joints of elbow and wrist.
  3. A time/event counter (as previously described) collects data regarding errors and total steps.

 

The training of whole-limb rotation (relationship of the foot to the pelvis) is presently in the stage of equipment development ( Figure 4 ). It is believed this equipment may be of significant use in gait training.

Results to Date. Investigations in this area are presently conducted as individual case studies. Problems of extreme knee flexion or hyperextension during the stance phase of gait are the main area of concern. Specific questions being investigated are:

 

  1. Appropriate selection of candidates.
  2. Variations in training programme necessary for various problems.
  3. Technical precedures necessary to ensure reliable and accurate feedback, considering the fact that equipment is applied daily and daily calibration is impractical.

 

Several children have completed a training programme for knee position, and the results indicated several features:

 

  1. The children responded quickly to the demands of the feedback system and achieved the pre-set goals in a matter of days. Figure 5 is an example of this feature. It represents the first stage in training a young man to prevent hyperextension of the left knee during stance. The training task was 25 repetitions of lifting the right leg clear of the floor while maintaining knee flexion of the left.
  2. The degree of learned control was also remarkable, considering the degree of accompanying spasticity. This same patient was in the fourth stage of recovery as defined by Brunnstrom 2 . He learned to maintain his knee between neutral position and 30 degrees of flexion during stance, even though the degree of spasticity remained the same throughout training.
  3. The generalization of the learning has been poor. This may reflect an inadequate length of training time or inadequate withdrawal procedures. These aspects will be studied further.

 

Conclusion

Experience to date with biofeedback training systems suggests that they may be a significant new tool for rehabilitation practitioners. Through this approach, the patient is allowed to monitor continuously his own movements and progress in a clinical setting; longer practice time can be planned since direct supervision often is not required. A situation is created in which the patient takes an active role in his own rehabilitation process and has the opportunity to improve at a faster rate than traditional methods allow.

References:
1. Basmajian, J. V., New vistas in electromyography. J Can Physiother Assoc, 21:1:11-17, 1969.

2. Brunnstrom, S., Movement Therapy in Hemiplegia. Harper & Row, New York, 1970.

3. Chase, M. H., The matriculating brain. Psychology Today, 7:1:82, 1973.

4. Harris, F. A., F. A. Spelman, and J. W. Hymer, Electronic sensory aids as treatment for
cerebral palsied children. Phys Ther, 54:354-365, 1974.

5. Jonas, G., Visceral Learning: Towards a Science of Self-Control. Viking Press, New York, 1973.

6. Klinge, V., Effects of exteroceptive feedback and instructions on control of spontaneous
galvanic skin response. In Shapiro, D., et al., eds., Biofeedback and Self-Control. Aldine
Publishing Co., Chicago, 1972.

7. Rugel, R. P., et al., Use of operant conditioning with physically disabled child. Am J Occup Ther, 25:247-249, 1971.

8. Wooldridge, C. P., and G. Russell, Head position training with the cerebral palsied child:
an application of biofeedback techniques. Arch Phys Med Rehabil, 57:407-414, 1976.

9. Wooldridge, C. P., and C. A. McLaurin, Biofeedback: background and applications to physical rehabilitation. Bull Prosthet Res, 10-25, Spring 1976.