Deltoid Disruption

ExitCare ImageA deltoid disruption is a rare injury in which the deltoid muscle detaches fully or partially from one of the bones of the shoulder (acromion), the shoulder blade (scapula), or both. This results in a partial loss of shoulder function, because the deltoid muscle is very important in the functioning of the shoulder joint. The deltoid muscle assists in raising the arm in front of you (flexion), raising the arm behind you (extension), and raising the arm to the side (abduction) of the shoulder joint. A deltoid disruption may also occur as the attachment of the deltoid muscle to the arm bone (humerus). However, this injury is even more uncommon.


  • A "popping" or tearing sensation felt at the time of injury.

  • Severe pain in the shoulder at the time of injury.

  • Tenderness, swelling, warmth or redness, and later bruising over and around the shoulder.

  • Shoulder weakness or inability to use the shoulder properly.

  • Changed contour of the shoulder either visually or felt by touch. This is more evident when trying to contract the muscle or lift the arm.

  • Loss of firm fullness when pushing on the area where the tendon ruptured (a defect between the end of the muscle and bone where they are separated from each other).


  • Sudden episode of stressful over activity, particularly a major force to an already maximally contracted deltoid muscle.

  • Direct blow or injury.

  • Possibly, throwing.

  • Shoulder surgery (particularly on the rotator cuff).


  • Sports that require excessive deltoid muscle stress, especially throwing sports.

  • Contact sports.

  • Poor shoulder strength and flexibility.

  • Previous shoulder injury or surgery requiring movement of the deltoid.

  • Oral anabolic steroid use.


  • Warm up and stretch properly before activity.

  • Allow for rest and recovery between activities.

  • Maintain physical fitness:

  • Cardiovascular fitness.

  • Shoulder flexibility.

  • Muscle strength and endurance.


This condition is usually curable with early and appropriate treatment.


  • Weakness of the shoulder, especially if untreated.

  • Re-rupture of the muscle after treatment.

  • Prolonged disability.

  • Risks of surgery, including infection, injury to nerves (numbness, weakness, or paralysis), bleeding, hematoma, shoulder stiffness, shoulder weakness, pain with strenuous activity, and recurrent disruption.

  • Loss of shoulder contour.

  • Inability to repair deltoid.


Treatment initially involves using medicine and ice to reduce pain and inflammation. Heat therapy may be used for small injuries. Strength and stretching exercises may be recommended and may be performed at home or with a therapist. For large ruptures, surgical interventions are usually required. Deltoid repair surgeries are often difficult, because the deltoid tendon does not hold stitches well. If the rupture occurs in the muscle body, a repair cannot be made. In order to have the best likelihood of a good outcome with surgery, it is important for the injury to be treated within a few weeks of injury. After surgery, the shoulder may be immobilized for a period of time and physical therapy may follow.


  • If pain medicine is necessary, nonsteroidal anti-inflammatory medicines, such as aspirin and ibuprofen, or other minor pain relievers, such as acetaminophen, are often recommended.

  • Do not take pain medicine for 7 days before surgery.

  • Prescription pain relievers may be given if determined necessary by your caregiver. Use only as directed and only as much as you need.


Cold treatment (icing) relieves pain and reduces inflammation. Cold treatment should be applied for 10 to 15 minutes every 2 to 3 hours for inflammation and pain and immediately after any activity that aggravates your symptoms. Use ice packs or an ice massage.


  • Pain increases, despite treatment.

  • Any of the following occur after surgery:

  • Signs of infection, including fever, increased pain, swelling, redness, drainage, or bleeding in the surgical area.

  • New, unexplained symptoms develop. Drugs used in treatment may produce side effects.