The infraspinatus muscle is one of the four rotator cuff muscles. It works in conjunction with supraspinatus, teres minor, and subscapularis to stabilize the shoulder joint throughout movements.
The infraspinatus, specifically, acts as an external rotator of the shoulder and is located along the posterior shoulder blade, or scapula. In order to appreciate the effects of this muscle’s actions, we need to tie in real life circumstances to make sense of these scientific words.
Daily activities like reaching to the back seat of your car, or washing your hair in the shower, or scratching your upper back have an external rotation component that the infraspinatus muscle assists in achieving.
Dr. Carlos Tandron states, "The rotator cuff muscles play such an important role in the function of the shoulder joint complex. It is so important to be properly evaluated when you have shoulder pain or the inability to lift your arm over your head." Dr. Tandron is board certified by the American Board of Orthopaedic Surgery, and subspecialty certified in Sports Medicine.
To learn more about the Anatomy of the Shoulder Joint, please watch this Shoulder Anatomy Video.
Injury to the infraspinatus muscle commonly occurs due to overuse of the shoulder in recreational activities, work-related activities, or history of shoulder instability.
We find that most of these activities include some sort of overhead reaching, lifting, or pushing which stresses the shoulder joint and leads to both instability and joint laxity. Whenever there is instability within the joint we worry about possible tearing of the muscles surrounding that joint.
Overhead athletes are frequently susceptible to an infraspinatus tendon tear or strain due to the constant overhead motions stressing the joint.
When pathology is present pain symptoms commonly occur in the upper back or down into deltoid/bicep area. This is sometimes confusing to patients how feel like something is wrong with the deltoid or bicep muscle. This is due to the body’s pain referral patterns.
The rotator cuff pain referral pattern is the upper shoulder and anterolateral upper arm. Patients with an infraspinatus tendon tear will also have pain while sleeping, reaching overhead, working on the computer, and reaching behind.
They may also experience weakness in the affected arm causing them to predominately utilize their other arm as compensation.
In order to treat an infraspinatus tendon tear, one must be evaluated in order to know the severity of the injury and be guided in the best course of treatment. If the tear is not significant or the patient does not require maximum stability within the shoulder for daily activities, work requirements, or recreation the best treatment option may be conservative care.
This plan would include physical therapy focused on resolution of range of motion restrictions, strengthening of the rotator cuff and other scapular supportive muscles, postural and body mechanics adjustments as necessary, and anti-inflammatory treatment including ice and soft tissue mobilization.
On the other hand, if the infraspinatus tendon tear is severe in nature and the patient requires the return of maximum shoulder stability surgical intervention may be suggested as the best option. This would include reattaching the healthy tendon to the insertion site of the shoulder complex.
A bout of post-operative physical therapy would then be prescribed in order to regain range of motion, strength, and use of the affected arm in an appropriate timeline. To learn more about impingement of the shoulder, please go to:Impingement.
Infraspinatus tendon tears frequently occur in overhead athletes, as a result of overuse injury, or in chronic shoulder instability. The main complaints are pain while sleeping, weakness in the affected arm, and inability to move the arm in certain motions. Conservative or operative treatment options are available based on severity and complexity of each individual case. To learn more about rotator cuff exercises, please read this ARTICLE.
If you want to learn more, go to our medical library at JOIONLINE.NET. To make an appointment by Telehealth or in person with a JOI Orthopaedic Knee Specialist, please call JOI-2000, schedule online or click below.