The shoulder has more range of motion than any other joint in the body. It’s actually 3 separate joints, controlled by 26 different muscles, so a lot can go wrong.
Common causes of shoulder pain include:
- Acromioclavicular (AC) joint arthritis
- AC joint sprain
- Rotator cuff tears
- Calcific tendinitis
- Glenohumeral joint arthritis
- Impingement syndrome
- Rotator cuff tendinitis
- Shoulder dislocation and instability
- SLAP tear
- Biceps Tendonitis
Acromioclavicular (AC) joint arthritis
Caused by ‘wear and tear’ of the AC joint, the joint on the top of the shoulder that connects the scapula (shoulder blade) to the clavicle (collarbone). As the joint wears out, the ends of the bone rub, and become painful. Bone spurs may develop, causing pressure on the muscles underneath.
Common Causes
There may be an old history of an AC sprain, or other shoulder injury. Weightlifters are prone to this condition at a younger age. Often no cause is found, other than ‘wear and tear’.
Symptoms
Pain, generally on the top of the shoulder, which may radiate up to the neck, the upper arm, or the back of the shoulder. Pain is usually worsened with sleeping on the side, lifting, and reaching across the body.
Physical Findings
Tenderness at the AC joint, positive physical exam tests.
Workup
Physical exam and x-rays are diagnostic.
Non-operative Treatment
Anti-inflammatory medications, and a trial of a corticosteroid injection. Physical therapy often aggravates symptoms.
Surgical Treatment
Shoulder arthroscopy, with removal of a small portion of the end of the collarbone, so that the two bones do not rub anymore.
Injury Comment
Generally this condition slowly progresses, and non-operative treatment is of limited relief. Most of the time, the entire surgical procedure can be done arthroscopically, without a large incision, and with rapid return to full activities and pain relief.
Acromioclavicular Joint Sprain
Injury to the joint on the top of the shoulder, with partial (grade 1 & 2) or complete (grade 3) tearing of the ligaments with dislocation of the AC joint.
Common Causes
Usually caused by a fall onto the shoulder, occasionally by lifting heavy objects.
Symptoms
Pain on the top of the shoulder. May have bruising or swelling at time of injury. There are often complaints of ‘popping’. May develop a ‘bump’ or deformity on top of the shoulder.
Physical Findings
Tenderness at the AC joint. Positive ‘AC joint compression test.’
Workup
Physical examination and x-rays are usually diagnostic. Occasionally, stress x-rays are required.
Non-operative Treatment
Rest, sling, and pain medication for grade 1 & 2 sprains, until symptoms subside. Most grade 3 sprains heal with time, although some physicians advocate early repair in the competitive athlete.
Surgical Treatment
Repair is performed by ‘relocating’ the dislocated joint, and repairing the torn ligaments.
Injury Comment
The majority of these injuries do heal with time, although a bony deformity is common. Surgical repair of the ligaments in grade 3 sprains may lead to faster recovery and better performance in certain athletes.
Rotator Cuff Tear
A tear in the muscles that attach to the upper arm at the shoulder joint. These muscles are involved in shoulder and arm motion, and may tear off of the bone, or in the substance of the muscle itself.
Common Causes
Lifting heavy objects, overhead use of the arm, a fall on the outstretched arm or other trauma.
Symptoms
Pain in the shoulder, often radiating down the side of the arm or up to the neck. Pain is worsened with using the arm overhead, lifting objects, or sleeping on the injured side. Patients often report weakness in the arm and shoulder, with stiffness, or loss of motion.
Physical Findings
Tenderness over the rotator cuff, weakness, pain with ‘impingement test’.
Workup
Physical examination, X-rays, possibly an MRI scan.
Non-operative Treatment
Physical therapy and anti-inflammatory medication, avoidance of aggravating activities.
Surgical Treatment
Arthroscopy, with arthroscopic or open rotator cuff repair.
Injury Comment
Rotator cuff tears generally do not heal on their own (the tendon retracts when torn, like a rubber band, and the torn edges are not adjacent to each other). Many rotator cuff tears can now be repaired arthroscopically, without a large incision. Following a rotator cuff repair, protection of the shoulder is usually required for several weeks, and full recovery may take many months.
Calcific Tendonitis
A buildup of calcium develops in the muscles that move the shoulder. This causes pain and inflammation.
Common Causes
Repetitive overhead use of the arm, frequent lifting: tennis, hammering, gardening, weightlifting; occasionally there is a history of trauma to the shoulder.
Symptoms
Pain in the shoulder or down the side of the arm. Pain with lifting the arm overhead, or sleeping on the injured side.
Physical Findings
Tenderness, positive ‘impingement test.’
Workup
X-Rays, physical examination and MRI (rarely).
Non-operative Treatment
corticosteroid injections.
Surgical Treatment
Shoulder arthroscopy, with subacromial decompression.
Injury Comment
Generally cured with non-operative care. Arthroscopy is highly successful, with an early return to activities, and extremely low risk of recurrence. Prolonged or worsening symptoms may be signs of a rotator cuff tear.
Glenohumeral Joint Arthritis
A wearing out of the ‘ball and socket’ joint of the shoulder. Progressive cartilage wear leads to bone rubbing on bone.
Common Causes
Most cases have no obvious cause. There is probably a genetic predisposition. Occasionally there is a history of an old injury.
Symptoms
Increasing aching pain in the shoulder, radiating down the arm. Aggravated with activity or motion of the shoulder, and relieved with rest. Sleeping on the involved side is usually very uncomfortable. Patients may report a grinding sensation.
Physical Findings
Tenderness along the glenohumeral joint of the shoulder. Decreased range of motion, with pain at the extremes of motion.
Workup
Physical examination and special x-rays are diagnostic.
Non-operative Treatment
Anti-inflammatory medication may reduce symptoms. A well-placed corticosteroid injection can bring substantial relief to some patients, for a long time.
Surgical Treatment
Either a shoulder arthroscopy and debridement, or Total Shoulder Replacement.
Injury Comment
Most patients can be managed non-operatively. A shoulder arthroscopy is a straight forward outpatient procedure that only washes out the joint; it doesn’t replace the worn-out cartilage, and is of variable success. A shoulder replacement is a much more substantial procedure, but reliably improves pain relief and function.
Impingement Syndrome / Rotator Cuff Tendonitis
Common Causes
Repetitive overhead use of the arm (tennis, hammering, gardening), frequent lifting, a fall on the shoulder or outstretched arm.
Symptoms
Pain in the shoulder or down the side of the arm. Usually fairly comfortable at rest. Pain with lifting the arm overhead, or sleeping on your side.
Physical Findings
Tenderness, positive ‘impingement test’.
Workup
X-Rays. and physical examination, MRI (rarely).
Non-operative Treatment
Rest, anti-inflammatory medication, physical therapy. Possibly a trial of a corticosteroid injection.
Surgical Treatment
Shoulder arthroscopy, with arthroscopic decompression
Injury Comment
Generally curative with non-operative care when treated early. Arthroscopy is highly successful, with an early return to activities. Prolonged or worsening symptoms may be signs of a rotator cuff tear.
Shoulder Dislocation / Shoulder Instability
The shoulder joint is like a ball and a cup. The ball (humeral head) is held in the cup (glenoid) by both the shape of the bones, and the ligaments and capsule surrounding the joint. With a shoulder dislocation, the ball comes out of the socket. For this to occur, the ligaments and capsule stabilizing the shoulder must tear or stretch. The labrum is a thin rim of tissue surrounding the edge of the shoulder socket. When the labrum tears, this is called a ‘Bankart lesion’.
Common Causes
Most shoulder dislocations are due to a traumatic injury, such as a fall. Occasionally an individual may develop a ‘loose’ or unstable shoulder with repetitive microtrauma (baseball pitchers, swimmers), or even without trauma.
Symptoms
A dislocation is obvious; the arm is held at the side, and cannot be voluntarily moved without severe pain. A loose, or unstable shoulder that is not dislocated may cause feelings of not being able to ‘trust’ the shoulder. This is especially true when the arm is overhead and out to the side. There may be a sense of ‘catching’ in the shoulder, followed by vague aching.
Physical Findings
A positive ‘apprehension’ test, or being able to recreate the feeling that the shoulder is about to ‘come out of the socket’.
Workup
The diagnosis is primarily based on history and physical examination. X-rays are occasionally helpful. An MR scan may show a tear in the labrum.
Non-operative Treatment
Prolonged immobilization after a dislocation probably doesn’t reduce the risk of redislocation. Aggressive physical therapy, working on strengthening the muscles around the shoulder, can reduce symptoms, but may not prevent recurrence.
Surgical Treatment
The ligaments holding the ball in the socket are repaired(if torn), or tightened (if loose). This may be done either arthroscopically with a fiberoptic camera, or with an open procedure.
Injury Comment
Recurrent dislocation is the main complication with this type of injury. The risks of recurrence and chronic instability are much greater in the younger individual, and decrease with age.
Slap Lesion
The labrum is a thin ring of tissue that surrounds the rim of the shoulder socket, deepening the socket and increasing the stability of the shoulder joint. At the top of the socket, or ’12 o’clock’ position, the biceps tendon also inserts into the labrum. A SLAP lesion stands for a tear of the superior labrum, from anterior to posterior.
Common Causes
A traction injury, such as catching oneself falling, is a common cause. A fall on the outstretched arm, or repetitive activities such as pitching may predispose to this injury.
Symptoms
Pain in the shoulder, occasionally radiating down the arm. A sense of catching may be felt, or deep aching that persists.
Physical Findings
Difficult to diagnose on physical examination. Must have a high degree of suspicion.
Workup
X-rays are rarely helpful. MR scans are frequently inaccurate. A well-placed injection of local anesthetic into the shoulder joint will temporarily relieve symptoms, suggesting the diagnosis.
Non-operative Treatment
Anti-inflammatory medication and rest may reduce symptoms.
Surgical Treatment
Arthroscopic surgery, with either repair of the torn tissue, or removal of the torn piece, depending on the injury.
Injury Comment
This injury is often seen with other shoulder injuries, such as shoulder instability, or a rotator cuff tear.