Synonyms in a broader sense
- Biceps muscle
- Biceps Tendon
- Rupture of biceps tendon / biceps tendon rupture
- SLAP lesion.
Anatomy
The biceps muscle (Muskulus biceps brachii), called biceps for short, belongs to the upper arm flexor muscles at the front of the upper arm. It is a double-jointed muscle that runs over the shoulder joint and the elbow joint. The biceps muscle /biceps has two sinewy origins: The biceps muscle /biceps makes up the majority of the outer structure of the front upper arm.
The biceps muscle /biceps ends with a tendon. The tendon starts at a stable roughness of the radius (tuberosity radii) of the spoke bone. The tendon is very thick and stable.
An extensive parathyroid tendon radiates into the muscular forearm sheath (fascia). – The long biceps tendon has its origin at the upper edge of the glenoid cavity. This origin is also called the biceps tendon anchor.
From its origin, it runs through the glenoid joint to the head of humerus, where it continues in a bony groove (sulcus bicipitalis) towards the muscle belly. At the front of the shoulder, at the head of the humerus, the long biceps tendon can be felt well in its groove. – The short biceps tendon of the biceps muscle/biceps has its origin at a continuation of the shoulder blade, the coracoid. The tendon runs diagonally downwards to the common muscle belly at the front of the upper arm.
Function
The biceps muscle /biceps has functions for the movement of the shoulder and elbow joints. With its two origins, the biceps muscle /biceps acts as a lateral lifter (long biceps tendon = abductor), spreader (short biceps tendon = adductor), internal twister and lifter (both) of the upper arm. In the area of the elbow joint, the biceps muscle/biceps acts as the strongest forearm flexor and inner twister of the forearm (supinator = turn palm towards the ceiling). By means of specific examination techniques, the biceps muscle/biceps can be tightened to such an extent that characteristic pain occurs in the event of an injury.
Diseases
The long biceps tendon is particularly susceptible to injuries to the biceps muscle/biceps. Chronic damage to the shoulder joint and instability in the humeral groove can lead to inflammation (tendovaginitis bicipitis) or even complete rupture of the biceps tendon (biceps tendon rupture). Even the layman can impressively recognize the rupture of the long biceps tendon by the slipped down muscle belly at the level of the lower upper arm due to the missing upper suspension.
A tear of the short biceps tendon is very rare. Rarely, although occasionally, the strong biceps tendon attachment also tears at the level of the elbow joint. While a rupture of the long biceps tendon does not necessarily require surgery and is functionally well tolerated, a rupture of the biceps tendon attachment is associated with a considerable loss of function, which is why surgical intervention is necessary.
Painful injuries to the biceps tendon anchor (SLAP – lesion) are difficult to diagnose. They are difficult to grasp during physical examination and are often overlooked even in an MRI examination of the shoulder.
