Chronic pain is very often from strain (tendon damage) or sprain (ligament damage) which can occur for injuries or just overuse. This is because many nerve endings are present in tendons and ligaments and when stretched due to weakness in the structure, they will cause pain. The patient feels tight as muscles try to protect the area but the problem is loose or weak connective tissue. Normal repair takes 6-8 weeks and is often incomplete. Normal repair attempts to thicken and tighten the weak and loose tendon/ligament and requires growth factor elevation. If the tendon or ligament does not get tight or strong enough, the muscles stay chronically tight causing stiffness and the nerves continue to be stimulated causing pain with movement or at rest.
Growth factors elevation is only increased for several weeks after injury. Injection to raise growth factor levels causes the repair cycle to be repeated, allowing the tendon or ligament to get stronger and then decrease or eliminate symptoms. Indications of damage to tendons/ligaments can include referred symptoms such as pain, numbness, or coldness, symptoms of looseness such as clicking, popping, or feeling out of place or loose and secondary changes in muscle such as weakness, tightness, or twitches seen in muscle with stimulation of the weak/irritable area in the tendon/ligament. (Twitch contractions.)