Vita TU, Occupational Therapist and Project Manager
Sunshine Social Welfare Foundation
Scar contracture is the main factor affecting functional recovery after burns. This is especially true when scars span the joints, as they can easily cause limited range of motion. To get a better idea of the level of joint limitation caused by scar contracture, therapists will usually measure single joint range of motion but good range of motion for a single joint does not necessarily mean good function? If that is the case, what kind of measurement can be used to reflect actual functional performance? In this article, we will explain why measuring multiple joint ROM is important and how to use Total Active Motion (TAM) to assess functional performance.
Why relying on single joint ROM to assess functional performance is not enough
If the patient has scars on the dorsal side of the hand, he may be able to perform wrist flexion, MP flexion or IP flexion individually, but if we ask him to simultaneously perform wrist flexion, MP flexion and IP flexion to form a fist, the pulling of the scar may make it difficult or even impossible to perform the movement.
That’s because when multiple joints in close proximity move at the same time in the opposite direction of scar contracture, the demand on scar pliability will be higher than for a single joint movement. Therefore, when one joint achieves full range of motion, it does not mean it can achieve ideal range of motion when involved in a multiple joint movement. By the same logic, single joint ROM does not reflect the whole picture of the hand’s functional performance. In addition, single joint ROM measure cannot reflect the potential impact of tendon adhesion.
What is Total Active Motion (TAM) and how to use it to measure composite ROM?
TAM assessment is performed by asking the patient to do MP flexion, PIP flexion and DIP flexion simultaneously. The degree of flexion of each joint is measured and the total is added up. Then, the patient places all the joints in extension and the total extension deficit is added up. A finger’s TAM is the sum of active flexion of this finger, minus the sum of extension deficit of this finger. TAM is calculated for the index, middle, ring and little fingers.
When measuring TAM, the four fingers must perform active flexion or extension all at once, otherwise the accuracy of the range of motion being measured will be affected.
So why is TAM useful in burn rehabilitation?
TAM can help identify impairments of fingers that are only obvious during multiple joint movements like composite flexion or composite extension. It can thus give us a better idea of the functional impairment faced by the patient. By measuring TAM over time, we are better able to see improvements in composite ROM and by extension, in functional performance.
Carole Johnson, RPT, Loren H. Engrav, MD, David M. Heimbach, MD, Janet A. Marvin, RN, MN, EVALUATING FUNCTIONAL HAND RESULTS AFTER DEEP DERMAL BUMS WITH TOTAL ACTIVE MOTION MEASUREMENTS, The Journal of Burn Care & Rehabilitation, Volume 1, Issue 2, November-December 1980, Pages 19–21
Reg Richard etc., Burn Hand or Finger Goniometric Measurements: Sum of the Isolated Parts and the Composite Whole. Journal of Burn Care & Research. 2017, 38:6, e960-e965.