We're now going to turn to two larger, better-known muscle-tendon units, the biceps and the triceps. Like the biceps, the triceps each crosses two joints: the elbow and the shoulder. Most triceps injuries happen near the elbow.
Anatomy & Injury Causes
The triceps muscle is the primary extensor of the elbow, and therefore functions as an antagonist to the biceps. Located in the posterior shoulder and back of the upper arm, the triceps makes up roughly 2/3 of the arm's muscle mass, and in healthy people it is very strong. As its name suggests, the triceps has three distinct heads, but at the distal end, these merge together into one common tendon. This tendon inserts on the olecranon process, with some fibers radiating into the fascia of the forearm. The most frequent sites of injury at the elbow are the tenoperiosteal junction, where the tendon meets the bone, and the tendon body.
Triceps injuries are a little less common than biceps injuries. They can be caused by athletic activities and exercises that require rapid, forceful extension of the elbow (such as push ups or dips); by lifting much more weight than you are able to; or by repetitive hammering or throwing motions. The triceps is particularly vulnerable when attempting a very strenuous motion starting with the elbow in full flexion — for example, moving from that position into a push-up or a bench press at your weight limit.
The primary test for triceps injury is resisted extension. Place one or both of your hands under the client's wrist as the client holds the arm at a right angle in front of their body. Now, ask the person to push down forcefully as you resist, pushing up with equal and opposite force. Elbow pain on this test indicates that the triceps is injured.
In some cases, the triceps muscle is so strong that even though it's injured, this test fails to produce pain. If you get a negative result but still suspect a triceps injury, take the person into full elbow flexion — so the muscle is stretched, and therefore a little weaker — and then repeat the test. This gives you a much better chance of revealing the injury.
As with the biceps test, if the client can overpower you, it's best to protect yourself from injury by having them lie supine. Lace your fingers together, wrap them around the ulnar side of the forearm just above the wrist, and lean back. In this position, the client would have to pull your entire body weight to overpower you.
The most effective treatment approach for the triceps is a combination of friction therapy, massage therapy, and exercise therapy. The injured portion of the tendon will be painful on palpation. If you have difficulty pinpointing the precise site of injury, try having the person extend their arm against resistance, so that the tendon tightens and pops up, and then palpate the tendon again in that position.
Friction therapy is done with no lubricant so that you can pin the injured fibers against the bone and perform a friction motion against that resistance to break up the adhesive scar tissue. Be careful to take the skin with you, rather than rubbing over it. When performing any friction therapy techniques, work for 10 to 12 minutes at a time, taking breaks as necessary. Remember to change hands frequently so you don't strain yourself. Follow the friction therapy with deep massage to the upper arm, lower arm, and shoulder, and repeat twice a week for four to six weeks.