What is Glenohumeral Internal Rotation Deficit?
Glenohumeral Internal Rotation Deficit (GIRD) is a condition in which the internal rotation of the shoulder joint is limited. An individual with GIRD lacks the flexibility to bring the arm across the body or behind the back. GIRD can affect one or both shoulders and can cause a variety of shoulder problems, especially in throwing athletes.
What causes Glenohumeral Internal Rotation Deficit?
GIRD is often caused by tightness of the posterior capsule or rotator cuff muscles of the shoulder, which are overstretched and overloaded during throwing motions. This tightness can lead to altered shoulder kinematics, increased stress on the anterior structures, and impingement of the rotator cuff tendons or labrum against the glenoid rim. GIRD can also be associated with other shoulder injuries, such as SLAP tears, biceps tendonitis, or anterior instability.
What are the Signs and Symptoms of Glenohumeral Internal Rotation Deficit?
GIRD can lead to various shoulder problems, such as pain, inflammation, decreased range of motion, strength, and stability, increased risk of injury and degeneration. Some common signs of GIRD are:
- Decreased internal rotation and increased external rotation of the shoulder compared to the opposite side
- Loss of total arc of motion of the shoulder
- Positive impingement tests
How is Glenohumeral Internal Rotation Deficit Diagnosed?
GIRD is diagnosed by measuring the shoulder's range of motion in internal and external rotation with the arm at 90 degrees of abduction. A difference of more than 20 degrees of internal rotation between the throwing and non-throwing shoulder is considered abnormal. X-rays or MRI, may be ordered to rule out other causes of shoulder pain or dysfunction.
How is Glenohumeral Internal Rotation Deficit Treated?
Treatment of GIRD involves addressing the underlying causes and restoring normal shoulder range of motion, balance, and stability. Some common interventions are:
- Stretching exercises for tight muscles or capsules, strengthening exercises for weak muscles or stabilizers.
- Manual therapy for mobilizing stiff joints or tissues.
- Throwing mechanics and frequency modification to prevent further damage to the shoulder.
- Surgery to repair any associated lesions that require intervention.