How does bicep tendonitis happen?
The bicep musculotendinous junction is put under a lot of different forces moving through its attachment site. Even if you do not do any classic weight lifting training in the gym, you definitely lift your shoulder multiple times during the day, when washing your hair or picking up groceries or kids. Pushing or pulling actions, like planking, pushups or moving heavy loads on a trolley in (checkers & makro), all accumulate forces through the shoulder and bicep tendon. Excessive forces that you are not used to, like starting a new exercise routine or hanging curtains, can cause micro-tears and irritation in and around the bicep tendon. This combination of overload and overuse leads to swelling of the tendon which further impedes it’s recovery, leaving you stuck in a cycle of tissue decay. This causes bicep tendonitis.
Injury to the transverse humeral ligament, which keeps the bicep tendon within the groove of the humerus, can cause the tendon to dislodge and slide in and out. This friction can cause bicep tendonitis.
If you train or work in a bad position, like most of us do these days, hunched over steering wheels or screens all day, we increase our risk of developing bicep tendonitis. Bad posture pulls your shoulder joint forward. The shoulder blade lifts and rotates on the ribcage, changing the angle from where the bicep tendon generates its force. When you now load this joint even more, think chaturanga descends or lowering into a pushup, you load an already lengthened bicep tendon expecting it to lift you back up. No wonder injury to the bicep tendon is common, leading to bicep tendonitis.
Laxity of the ligaments or instability of the joint leads to excessive translation of the humeral head on the glenoid fossa and increases the force that the bicep needs to generate from a lengthened position. This can cause bicep tendonitis.
Previous injuries, like rotator cuff strains or tears and glenoid labrum tears can put you at higher risk of developing a bicep tendonitis.