It has been established that prolonged immobilization can delay recovery and adversely affect normal tissues. It has also been proven that mobilization will stimulate collagen synthesis, increase strength, and help align the repair cells and collagen fibers.1,2 Sutker, et al.,2 demonstrated an increase in cell number, DNA synthesis and collagen production in rat medial collateral ligament fibroblasts using cyclic load.
There are many studies corroborating the beneficial effects of manual loading on soft tissues. It has been proven that friction massage increases fibroblastic proliferation, which synthesize and maintain collagen, fibronectin, proteoglycans and other proteins of the connective tissue matrix.3 Even in the embryo, the joint differentiates from the interzonal mesenchyma under the influence of fetal motion.4 Motion enhances transsynovial nutrient flow, which provides nourishment to cartilage, menisci and ligaments. Immobilization of the adult rat knee with weightbearing showed muscle atrophy and fibrofatty connective tissue in the intercondylar notch within two weeks.5
Early or excessive motion can create strain at the cellular level, increase the inflammatory reaction, and damage repair tissue. Therefore, it is necessary to provide painless motion in the earliest stages of a lesion if possible. Light friction massage is often used after a strain/sprain and heavier friction at later stages.
An interesting study just appeared1 that attempted to determine the effect of mechanical strain on tendon cells, based on the amount of time the strain was exerted on the cells. Researchers mobilized (mechanically strained) human tendon fibroblasts from patellar tendons for different time intervals against controls, and found that the length of time of stress affected the amount of cellular proliferation. They stretched the cells for 15, 30 and 60 minutes and tested for fibroblastic proliferation after six, 12 and 24 hours. They noted a biphasic response. After 6 and 24 hours, there was increased cell proliferation, and less after 12 hours. After strain stimulation for 30 minutes, there was a lower proliferation rate of tendon fibroblasts. The authors hypothesized that when the cells were exposed to 30 minutes of cyclic-biaxial strain, cell damage may have occurred, and there was no longer an increase in cellular proliferation. They thought that the 30 minutes of strain might have lead to programmed cell death (apoptosis). But 60 minutes of cyclic strain caused an increase in cellular proliferation after 6 and 24 hours. They hypothesized that a longer strain time activated protective processes. Further studies are needed to determine the necessary time.
Although English medical pioneer Dr. James Cyriax wanted his therapists to friction for 20 minutes, in practice they frictioned for about 10 minutes. I usually friction areas for about five to eight minutes, but find myself increasing the friction time if results do not occur in expected time.
References
- Zeichen J, Briensven M, Bosch U. The proliferative response of isolated human tendon fibroblast to cyclic biaxial mechanical strain. Amer J sports Med 28(6), 2000:888-892.
- Sutker BD, Lester GE, Banes AJ, et al. Cyclic strain stimulates DNA and collagen synthesis in fibroblasts cultured from rat medial collateral ligaments. Trans Orthop Res Soc, 1990, 15:130.
- Hammer W. Functional Soft Tissue Examination and Treatment by Manual Methods: New Perspectives, 2nd. ed. Gaithersburg, MD, Aspen. 1999:461.
- Akeson WH, Amiel D, Abel MF et al. Effects of immobilization on joints. Clin Orth & Rel Res 219, 1987:28-37.
- Evans EB, Eggers GW, Butler JK. Experimental immobilization and remobilization of rat knee joints. J Bone Joint Surg 42A, 1960:737.
Warren Hammer,MS,DC,DABCO
Norwalk, Connecticut theham@discovernet.net
