Tendinitis literally means inflammation of the tendon. In fact, any time you see the suffix “-itis” behind a name of a body part it means inflammation of that body part. As an example, inflammation of the Larynx is called laryngitis. But let’s get back to the causality of tendinitis. Every tissue in the body is formed on what is called a “collagen matrix.” In fact, we can consider collagen as the building blocks of all tissue. Each tissue has varying amounts of collagen. Collagen is in its highest concentration based on the stiffness of that tissue (or, it’s resistance to injury). The collagen matrix concentration in the Skeletal-Muscle System in order is; bone, ligament, tendon and finally muscle. Further, the collagen fibers are uniquely positioned such that they are aligned in positions which offer the greatest resistance to the forces under which that tissue must absorb. As an example, jumping off the tailgate of a truck will not fracture the bones in your leg. However, if the same force hits your thigh bone (femur) directly from the side, it will immediately fracture. This is due to the directional nature of the collagen matrix. In the femur, the matrix is set up only to absorb forces that transfer the length of the bone. It is also important that you understand blood flow in these tissues. Blood flow is inversely proportional to the amount of collagen a tissue contains. Muscle has the greatest amount of blood flow and the lowest concentration of collagen, while bone has the least amount of blood flow in the highest concentrations of collagen. When put under a microscope muscle fibers appear red and bone fibers appear white. When put under a microscope, a tendon will also appear white. This means its blood flow is relatively low. When a tendon is stressed in a manner which goes against its collagen alignment, an injury can occur. This injury will cause micro tearing of the tissue and bleeding. This is why we call it “tendinitis.” Over time, and as the tendinitis continues to go untreated, the micro tearing can increase in size rendering the tendon too painful to use. Couple this with the fact that a tendon has relatively low blood flow, it is clear why a tendon will take longer to heal. Muscle, because it has a greater amount of blood flow typically takes about 2 to 4 weeks to heal. Tendons usually take 4 to 6 weeks to heal. Ligaments typically take 6 to 8 weeks to heal. And this is why when you have a fracture, you are casted for 8 weeks. Bone has the least amount of blood flow.
Treatment: if you feel it tendinitis coming on or, have been diagnosed with the tendinitis, here is the treatment protocol:
- Follow the principles of RICE (Rest, Ice, Compression, and Elevation) for the first 24-48 hours
- 0-2 weeks, stretching and isometric exercise, alternate heat and ice
- 2-4 weeks, stretching, light warm-up (exercise bike), strengthening exercises at 25-50% PME in the same alignment of the collagen matrix, stretch and ice after
- 4-6 weeks, stretching, moderate warm-up (exercise bike/treadmill/elliptical/fast walking), strengthening exercises at 50-75% PME in the same alignment of the collagen matrix, do not exercise through pain, stretch and ice after
- 6 + weeks, reintegration of normal exercise routine, do not exercise through pain, stretch and ice after.
Dr. Brett Purdom, PT, DPT, ATC, CSCS
Owner of The Foot Mechanic™