The biceps is located on the front of the upper arm and is made up of two muscle units that originate from the shoulder and insert on a bone in the forearm. The two units of the biceps are known as the short head of the biceps (which attaches to the shoulder blade at the coracoid), and the long head of the biceps (which attaches to the shoulder blade at the top of the shoulder socket). Biceps tendon injury can occur at one of its attachments on the shoulder blade or its attachment in the forearm. The majority of biceps tendon problems occur in the long head of the biceps tendon near its insertion at the top of the shoulder socket, often referred to as proximal biceps tendon injuries.
Injuries to the proximal biceps can range from an inflamed tendon (tendonitis), to a complete rupture. Injuries of this nature are common among individuals who participate in repetitive shoulder activities that involve the use of the arm above the head. In some instances of repetitive stress and irritation, the tendon can become weak and tear partially, causing fraying. In other instances, the tendon can completely tear from its attachment site. A complete tear may occur suddenly during an activity such as heavy lifting. Proximal biceps tendon injuries are also commonly seen in association with tears of the rotator cuff muscles around the shoulder, which may allow the biceps tendon to subluxate (move out of position) from its normal groove.
Injuries to the biceps tendon at the forearm, also known as distal biceps injuries, occur less frequently. Partial or complete detachment of the biceps tendon can occur from the radius, bone of the forearm where the muscle inserts. Often patients report a pop while using their arm for lifting or while their arm was jerked into a straight position. This is often accompanied by swelling, bruising, and a deformity at the arm.
The most obvious symptom associated with a proximal biceps tendon injury, is pain in the front of the shoulder joint with overhead activity. With documented tendon tears, patients often report a sudden, sharp pain and a “pop” feeling or sensation that occurs when the tendon tears. Most patients will report weakness in the shoulder or elbow depending on the location of injury. Bruising, and a change in the appearance of the front of the arm may occur as well. This bulge results as a result of the altered resting position/tension of the biceps muscle and is often called a pop-eye deformity.
To determine the proper course of treatment, Dr. Anz will perform a physical examination of the shoulder and arm, and will determine the patients level of pain, function, strength, and mobility. Specific physical exam tests for proximal biceps tendon injuries include the Speed’s test, Yergason’s test, and tenderness over the biceps groove. Specific tests for biceps tendon injury at the forearm include the hook test, passive forearm pronation test, and biceps crease interval test. In addition to specific clinical tests, an MRI to confirm a diagnosis may be necessary.
With biceps injury at the shoulder, if the diagnosis is consistent with biceps tendonitis or a strained tendon, Dr. Anz will usually recommend non-surgical treatment measures including rest, ice, anti-inflammatory medication, a change in daily activities that irritate the tendon, and physical therapy. In some instances, an injection into the tendon sheath can help decrease the inflamation/irritation at the tendon. In cases of a complete tear of the tendon at the shoulder, many patients still retain good function without surgery. However, some patients may exhibit symptoms of a deformity and cramping pain. In these scenarios, a biceps tenodesis may be appropriate. This involves surgery to reattach the torn tendon at a different location to alleviate cramping pain and restore a normal arm contour.
With biceps injury at the forearm, partial injuries typically do well without surgery. A period of rest and recovery is necessary. Complete tears of the biceps at the forearm are accompanied by a 30% decrease in forearm flexion strength and a 40% decrease in supination strength of the elbow. For some patients, this decrease in strength is acceptable and function/pain will not be a long term problem. For some patients, surgical repair is important due to their occupations and/or recreations.
In surgical scenarios, Dr. Anz will limit activities during the first portion of the recovery phase. He will also prescribe a thorough physical therapy rehabilitation program that will detail appropriate progress regarding motion and strengthening exercises. It is necessary to allow time for the tendon to heal to bone. It typically takes 2-3 months before patients can return to their normal functional activities.
To learn more about biceps tendon injuries, or for additional resources on arthroscopic shoulder surgery, please contact the Gulf Breeze, Florida orthopedic surgeon, Dr. Adam Anz located at the Andrews Institute.