Athletes who complain of deep buttock pain, pain when sitting, or deep, posterior, upper thigh pain may be suffering from high (proximal) hamstring tendon injury. Chronic high hamstring tendinopathy is becoming increasing recognized as a causative factor in both sitting and activity-related posterior hip pain.1-3 Unlike an acute tear, the pain usually comes on gradually and may be aggravated by repetitive activities, such as running or biking, and worsened by prolonged sitting.
How Does the Pain Develop?
The body has many tendons, which anatomically are fibrous tissues that connect muscle to bone. The proximal hamstring tendons connect the three hamstring muscles (the semimembranosus, the semitendinosus, and the biceps femoris) to the sit bone (ischial tuberosity), which is located in the buttocks at the bottom of the pelvic bone. These tendons are prone to injury, particularly in activities that require repetitive motion, such as running or rowing, or those that require prolonged sitting. (The distal hamstring tendons connect the hamstrings to the tibia, or shinbone, just below the knee joint.)
Hamstring tendon pain can become chronic when a damaged tendon fails to heal properly. It usually begins with one or more of the following conditions:
- A previous tear of the tendon (an acute injury) that failed to properly heal.
- Chronic tendinitis, an inflammatory tendon condition that can lead to non-inflammatory, degenerative changes to the structure or composition of the tendon (called tendinosis or chronic tendinopathy).
High (proximal) hamstring tendinopathy (sometimes spelled tendonopathy) can potentially cause significant pain and long-term disability.4-6 This pain and disability may be avoided by recognizing symptoms, seeking an accurate diagnosis and getting prompt treatment.
Hamstring Muscle and Tendons
The three hamstring muscles are located at the back of the thigh:
- The semimembranosus muscle
- The semitendinosus muscle
- The biceps femoris
All muscles have origins and insertions, where their tendons attach muscle to bone. In the pelvis the hamstring origin occurs at the bottom of pelvis on a bone called the ischial tuberosity (sit bone). The semitendinosus and biceps femoris muscles blend together and share a common origin at the ischial tuberosity (sit bone) called the conjoint tendon. The semimembranosus tendon has a separate origin just to the outside (lateral to) the conjoint tendon origin.7
While the conjoint tendon is the most commonly affected hamstring tendon, the symptoms, diagnosis, and treatment options for the semimembranosus tendon is the same.