What is the supraspinatus?
The supraspinatus is a muscle located in the upper back and shoulder area. It is one of the four muscles that make up the rotator cuff, a group of muscles and tendons that attach the upper arm bone (humerus) to the shoulder blade (scapula).
The main function of the supraspinatus is to help lift the arm out to the side (abduction) and to rotate the arm so that the thumb points upward (external rotation). It works together with the other rotator cuff muscles (infraspinatus, teres minor and subscpularis) as well as the deltoid and the trapezius muscle, to control and stabilize the shoulder joint during movement. (1)
Origin, insertion and function
Origin
The supraspinatus muscle originates from the supraspinous fossa, a shallow depression located on the upper surface of the scapula. It is one of the four muscles that make up the rotator cuff.
Insertion
The muscle then runs laterally and superiorly, passing over the top of the shoulder blade, to insert on the greater tubercle of the humerus.
Function
The main function of the supraspinatus muscle is to help lift and rotate the arm. Specifically, it helps to lift the arm out to the side (abduction) and also helps to rotate the arm so that the thumb points upward (external rotation). The supraspinatus muscle works together with the other rotator cuff muscles, as well as the deltoid muscle and the trapezius muscle, to control and stabilize the shoulder joint during movement. It is innervated by the suprascapular nerve.
Common signs of weak supraspinatus muscles
Signs of weak supraspinatus muscles may include:
- Difficulty lifting the arm out to the side or above the head
- Pain or discomfort in the shoulder or upper arm when lifting the arm or reaching overhead
- A feeling of weakness or instability in the shoulder
- A popping or clicking sensation in the shoulder when moving the arm
- Limited range of motion in the shoulder
- Tenderness or pain when pressing on the muscle or when it is stretched
- Pain or discomfort when lying on the affected shoulder
- Tendinitis or rotator cuff tear
It’s important to note that these symptoms may also be caused by other issues such as injury, arthritis or other medical conditions. A medical professional should be consulted to determine the cause of symptoms and provide an appropriate treatment plan.
Exercises that strengthen the supraspinatus
There are several exercises that can be used to strengthen the supraspinatus muscle:
External rotation:
Sit or stand with a light weight (such as a can of soup) in your hand and your elbow bent at a 90-degree angle. Slowly rotate your arm outward, keeping your elbow close to your body. Return to the starting position and repeat.
Lateral raise:
Stand with your feet shoulder-width apart and hold a light weight (such as a pair of dumbbells) in each hand. Slowly raise your arms out to the side, keeping your elbows slightly bent. Return to the starting position and repeat.
Scaption:
Stand with your feet shoulder-width apart and hold a light weight (such as a pair of dumbbells) in each hand. Slowly raise your arms out to the side and slightly forward, keeping your elbows slightly bent. Return to the starting position and repeat.
Reverse fly:
Stand with your feet shoulder-width apart and hold a light weight (such as a pair of dumbbells) in each hand. Keep your arms straight and slowly raise them out to the side and slightly behind you, keeping your elbows slightly bent. Return to the starting position and repeat.
Pull-up:
Using a pull-up bar, grasp the bar with an overhand grip and pull yourself up towards the bar, keeping your elbows close to your body. Slowly lower yourself back to the starting position and repeat.
It’s important to start with light weights and to do the exercises with proper form to avoid injury. It’s also important to check with a medical professional before starting any exercise program. As you get stronger, you can increase the weight or repetitions.
References:
- Jeno SH, Munjal A, Schindler GS. Anatomy, Shoulder and Upper Limb, Arm Supraspinatus Muscle. [Updated 2022 Aug 30]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK537202/