Generally speaking, subluxation of the long head biceps tendon from the bicipital groove has characteristic symptoms. These include pain, decreased range of motion, pain while throwing that is relieved by rest, a palpable snap at a certain point in the arc of motion, and pain with pressure to the front of the shoulder. Common signs are tenderness over the bicipital groove, pain and occasionally tenderness or swelling over the front of the shoulder, pain upon pressure to the front of the shoulder, and a reproducible pop in rotation of the humeral head.
However, the symptoms of our injuries varied greatly as far as pain, location, weakness, popping or clicking in the shoulder, decreased range of motion and loss of strength. In some, the pain was an occasional dull throbbing ache in the joint that could be aggravated by strenuous overhead work or even mundane activities. In others, the pain was constant and severe and we could physically press on areas that would hurt with pressure, usually in the front of the shoulder where the tendon had slipped. The degree of our impaired mobility varied just as much as the pain, and many of us had difficulty sleeping, especially on our side.
A definitive cause is uncertain. None of us can recall a specific moment in which we “became injured.” While we are all avid CrossFitters, most of us participate regularly in other physically demanding sports, activities, and occupations. We could have sustained our injuries through any number of means.
Considering the LBT often attaches to the glenoid at the labrum, this injury may be related to “SLAP tears” (superior labral tear from anterior to posterior) that sometimes afflict “throwing motion” athletes, such as Tennis, Baseball, Volleyball, Water Polo, or those who’ve suffered a bad fall. SLAP tears often occur where the biceps tendon anchors to the labrum. Tears to this region of the labrum are slow to mend as there is limited blood flow to the area and slower transport of needed healing elements carried within the blood, thus limiting the body’s ability to effectively and efficiently repair the injured area.
Certified Sports Massage Therapist, Sara Bosinger of Touch Therapy, suspects that the “tendon slip” phenomenon could be caused by a lesion, fray, tear, or stretch of the superior labrum at the insertion point of the long-head biceps tendon, thus causing the tendon to “slip” since it’s not being held correctly. This is perfectly logical and goes hand-in-hand with the SLAP tear phenomenon. However, it has crossed my mind that since the positioning of the LBT in the bicipital groove is held in place by the transverse humeral ligament (THL), and the tendon slips out of this groove, that a lesion, fray, tear or stretch could also be at the THL. However, current research suggests the THL overlying the bicipital groove is no longer considered as a crucial stabilizing structure unless the medial coracohumeral ligament is torn, and some research even questions the existence of the THL altogether. Recent studies indicate there is no distinct THL, rather, support of the LBT within the bicipital groove is likely a fibrous tissue extension of the subscapularis tendon.
The bicipital groove itself has a wide variance in the angle of its walls and during internal/external rotation of the arm, the biceps tendon swings from one side to the other. Thus, in a shallow groove the possibility of the tendon to slip out is potentially greater as it has a tendency to force it’s way over the groove’s walls.
As it turns out, this biceps tendon slip phenomenon is not an uncommon injury in athletes, especially overhead athletes and throwers. It even has an official medical diagnosis; “Subluxation of the Long Head Biceps Tendon from the Bicipital Groove”. Or, more simply, “Biceps Tendon Subluxation”.
There is no single definitive precursor to a Biceps Tendon Subluxation, but rather there are several. Direct physical trauma (like a fall or crash), repetitive throwing motions, SLAP tears or tears to the ligamentous pulley system of the shoulder, can ALL lead to a subluxation of the LBT.
For the ten of us who suffered from a LBT Subluxation, I’m sure the actual causal mechanism (injury/reason) behind the tendon slipping out of place varies athlete to athlete, as likely does the origin of the injury itself.
Jason’s next installment will focus on Prognosis and Prevention.
3, 3, 3, 3, 3, 3
AMRAP in 3 minutes
3 Power Cleans 135/85
Rest 1 minute and repeat for a total of 5 cycles.
Score is total number of rounds completed.