When treating cartilage injuries, stress-loading techniques are valuable as Physical Therapists encourage tissue healing. Lack of stress leads to poorly organized tissue growth. Progressing too fast, or too heavy can slow healing. Only when articular tissues begin the proliferative phase of healing should stress-loading techniques begin.
Cartilage distributes body weight in the joint. In joint (articular) cartilage, stress or misuse can create synovitis, and effusion (increased synovial fluid in the joint). Prolonged fluid in the joint may might:
- decrease the nutrition to internal joint structures due to harmful proteolytic enzmes
- cause thinning of the articular carti-lage
- decrease joint range of motion from the abnormally high joint pressure.
Beginning with ROM exercise, and slowing the rate of synovial fluid production in the joint with the use of ice is very effective. Progressing from Passive range of motion, to Active range of motion exercises, with help from thermal modalities (cold) will decrease joint effusion and helps internal joint structures to heal.
Begin stress loading the joint slowly and then increase the stress as the tissue moves to the final healing phases to facilitate appropriate growth. Research has shown that stiffness of cartilage tissue can be improved. By using a daily protocol of 1000-1500 repetitions of a functional activity (without fatigue), for a period of 3-6 weeks for compression and decompression stimulus.
It has been suggested that the intensity level be 30 % or less of maximal non-painful levels. Stress levels can be increased as maximal non-painful levels increase. By testing the patient in a functional closed kinetic chain test at Accelerate Physical Therapy, we determine how to stress the tissue. In our Load Tolerance Test, repetitions for both testing and training should be consistent in speed, and have solid control of the movement. Otherwise, compression forces can spike with high-speed loading, or gradually increase with cyclic loading. Either could retard healing.
Traditional therapy programs account for joint health with passive range of motion progressing to active assistive and active range of motion and modality use. Load Tolerance Testing followed by articular cartilage compression training allows us to objectively assess and progress cartilage tolerance for weight bearing activities.