"The Achilles tendon is the largest tendon in the body. It connects your calf muscles to your heel bone and is used when you walk, run, and jump. Although the Achilles tendon can withstand great stresses from running and jumping, it is also prone to tendinitis, a condition associated with overuse and degeneration”. But how does the Achilles tendon come under stress? After all tendons themselves would are not motile tissues, they merely connect the muscle to bone. So if the tendon doesn’t actually contract how can it cause itself to move? The muscle that the tendon is attached to has to move in order for the tendon to move and this will result in movement at the joint. So the muscle contraction (motile tissue) would be the primary reason for the tendon coming under stress because the tendon itself has no contractile tissue it is simply a ‘connector’
Why is this relevant? Let’s use an analogy; imagine you were holding an elastic band and you took a piece of paper and folded it over the elastic band and pulled it back like a ‘bow and arrow’. The elastic band represents the Gastrocnemius (calf) muscles and the paper represents the Achilles tendon. In a pulled-back position this demonstrates what happens when the calf muscles get tight (possibly due to trigger points or spasm) and you can imagine the all the stress from the tight calf muscles (elastic band) being absorbed by the paper. If the system remained in this position for a prolonged period of time the paper would eventually start to fray and weaken due to the mechanical stress caused by the pull of the elastic band.
This means focusing on the site of the pain, which is usually the Achilles tendon or the heel, might not be useful in reducing the stress on the Achilles tendon. It would make more sense to look higher up the system at the calf muscles because that’s the active motile tissue and is the predominant factor in the condition. Various techniques like ischaemic compression, acupuncture and dry needling are effective in treating trigger points and tight bands of muscle and once the muscle settles down, the stress on the Achilles tendon and the heel subsides. For better results the focus should shift away from the site of pain and should aim at understanding the underlying cause of the pain response which will always involve the motile tissues. If a tendon becomes inflammed it is very important to start looking at what moves the tendon because that is how we will get to the cause of the problem, it may sound obvious but many professionals still direct their approach toward the site of pain, and not the cause of the pain.