Updated: Dec 8, 2008
Shoulder dislocations may occur from a traumatic injury or from loose capsular ligaments. Different conditions may affect the stabilizing structures of the shoulder and, thus, negatively affect patients with shoulder dislocations.1
This article focuses on glenohumeral joint dislocation. Although acromioclavicular (AC) joint separations are sometimes called shoulder dislocations by nonmedical persons, these are not true shoulder dislocations. Shoulder dislocations occur when the head of the humerus comes out of its socket, the glenoid.
For excellent patient education resources, visit eMedicine's Breaks, Fractures, and Dislocations Center and Sports Injury Center. Also, see eMedicine's patient education articles, Shoulder Dislocation and Shoulder Separation.
Related eMedicine topics:Shoulder stability is maintained by the glenohumeral ligaments, the joint capsule, the rotator cuff muscles, the negative intra-articular pressure, and the bony/cartilaginous anatomy.
The main stabilizers of the shoulder joint are the ligaments and the capsule complex. Multiple ligaments are present, but the inferior glenohumeral ligament is the most important and the one most commonly injured during an anterior shoulder dislocation. The injury may be a tear of the ligament/capsule off one of its bony attachments, and/or it may cause a stretch injury to these structures.
Tears in the rotator cuff muscles may also lead to shoulder instability. Four rotator cuff muscles are present in the shoulder. They are found superficial to the glenohumeral ligaments and the bones. Large tears may lead to shoulder instability, even with intact glenohumeral ligaments. Instability of the shoulder can also occur from injury to the nerves that control the shoulder muscles, specifically the axillary nerve.
The shoulder is a very mobile joint; therefore, it is often placed in awkward positions during sports. Thus, the force from a fall or a blow may be sufficient to cause shoulder damage. If the force is strong enough, the athlete tears the ligaments/tendons, fractures the glenoid or humerus, and dislocates the shoulder.
Patients with a dislocated shoulder report a myriad of symptoms to their physician.
The physical examination in a patient suspected of having a dislocated shoulder should confirm what the clinician picked up from the history of the injury.
Approximately 95% of shoulder dislocations result from a major traumatic event, and 5% result from atraumatic causes. Distinguishing the type and severity of the event is important to determine the true etiology of the dislocation. This distinction is necessary to determine the treatment.1,2,5,6,7
With a traumatic dislocation, the cause is obvious; however, atraumatic dislocations can result for different reasons. Ligamentous lax shoulders may dislocate with little or no trauma. Patients with lax ligaments may have 2 loose shoulders, but only 1 may be symptomatic. Congenital causes, such as excessive retroversion of the humeral head or malformation of the glenoid, can lead to instability. Neuromuscular causes, such as injury to the axillary nerve or cerebral palsy, have also been associated with shoulder instability.
Acromioclavicular Joint Injury
Bicipital Tendonitis
Clavicular Injuries
Rotator Cuff Injury
Shoulder Dislocation
Swimmer's Shoulder
Glenoid labrum tear
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Specialty Site Radiology
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Joint Reduction, Shoulder Dislocation, Anterior
In the acute phase of a dislocated shoulder, therapy should be limited. The arm should be immobilized in a sling and swathed for 1-3 weeks. Active or passive shoulder abduction with shoulder internal rotation is permissible, and removing the arm from the sling to work in a neutral internal-external rotation position is desirable, because a neutral position may actually improve positioning of the torn anterior capsule to the glenoid. During this time, the patient should perform elbow, wrist, and hand ROM exercises.
A good adage during the first 3 weeks after a shoulder dislocation is to "keep the hand in view." While looking forward, the patient should never let his or her hand be placed in a position outside the line of vision. This instruction assures a midrange position that does not compromise apposition of the torn or stretched anterior capsular structures to the glenoid.
The recurrence rate for shoulder instability is highly dependent on the age of the patient. Nonoperative care should be performed first before entertaining the thought of surgery. Most patients are able to rehabilitate their shoulder with rest and physical therapy.1,5
In patients who have recurrent shoulder instability, operative care should be highly considered.2,6,7 Numerous studies have shown the increased likelihood of traumatic glenohumeral arthritis in patients with multiple shoulder dislocations. Operative care may consist of both open or arthroscopic treatment of the cause of instability.
After the initial period of immobilization, passive ROM exercises should begin. Older individuals should begin performing ROM of the shoulder after 1 week of immobilization, because these patients are prone to shoulder stiffness. Passive ROM exercises should include shoulder pendulum exercises and an overhead pulley system for the shoulder. Goals for passive ROM should be 30° of external rotation and 90° of flexion for the first 3 weeks, followed by 40° of external rotation and 140° of flexion for the second 3 weeks.
The rotator cuff may also have been injured during the dislocation, so the therapist should be cognizant of the status of the rotator cuff during the early phase of rehabilitation.
Athletes who demonstrate symptomatic instability during guarded physical therapy should be considered for an MRI evaluation and probable arthroscopic or open anterior shoulder tissue repair.
More vigorous therapy can be initiated after full passive ROM has been regained, usually after 6 weeks. Rotator cuff strengthening exercises can be initiated with the use of rubber tubing or weights. Because the rate of shoulder redislocation is so much higher in young adults, vigorous training and strengthening should be delayed until approximately 3 months after the injury. Swimming is an ideal exercise to regain shoulder strength and should be encouraged once strengthening exercises have begun.
Shoulder dislocations are extremely painful events. If relocation is not accomplished within an hour, anesthesia via conscious sedation is necessary in the emergency department setting. Medications for this technique are not discussed in this article.
Oral narcotic analgesics are reasonable for a period of days, but prolonged use is categorically inappropriate.
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Resource Center Pain Management: Pharmacologic Approaches
Pain control is essential to quality patient care. Analgesics ensure patient comfort, promote pulmonary toilet, and have sedating properties, which are beneficial for patients who have sustained trauma. A 3- or 4-day supply of hydrocodone or similar schedule III narcotic should be provided following shoulder relocation.
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Toxicity, Narcotics
Drug combination for moderate to severe pain.
1-2 tab or cap PO q4-6h prn
<12 years: 10-15 mg/kg/dose acetaminophen PO q4-6h prn; not to exceed 2.6 g/d acetaminophen
>12 years: 750 mg acetaminophen PO q4h; not to exceed 10 mg hydrocodone bitartrate per dose or 5 doses/d
Coadministration with phenothiazines may decrease the analgesic effects; the toxicity increases with CNS depressants or TCAs
Documented hypersensitivity; high altitude cerebral edema (HACE) or elevated intracranial pressure (ICP)
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
The tablets contain metabisulfite, which may cause hypersensitivity; caution in patients who are dependent on opiates, because this substitution may result in acute opiate-withdrawal symptoms; caution in the presence of severe renal or hepatic dysfunction
Drug combination for short-term (<10 d) relief of moderate to severe acute pain.
1-2 tab PO q4-6h prn; not to exceed 5 tab/d
Not established
Coadministration with aspirin increases the risk of inducing serious NSAID-related adverse effects; probenecid may increase the concentrations and, possibly, the toxicity of NSAIDs; may decrease the effect of hydralazine, captopril, and beta-blockers; may decrease the diuretic effects of furosemide and thiazides; monitor PT duration closely (instruct patients to watch for signs of bleeding); may increase the risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently
Documented hypersensitivity; third trimester of pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Caution in patients with impaired renal function, peptic ulcer disease, impaired thyroid function, asthma, hypertension, edema, heart failure, increased ICP, and erosive gastritis; duration of action may increase in elderly persons
Indicated for mild to moderate pain.
30-60 mg/dose based on codeine PO q4-6h or 1-2 tab q4h; not to exceed 4 g/d of acetaminophen
0.5-1 mg/kg/dose PO based on codeine q4-6h; 10-15 mg/kg/dose based on acetaminophen; not to exceed 2.6 g/d of acetaminophen
The toxicity of codeine increases with CNS depressants, TCAs, MAOIs, neuromuscular blockers, phenothiazines, and narcotic analgesics.
Rifampin can reduce the analgesic effects of acetaminophen; coadministration with barbiturates, carbamazepine, hydantoins, and isoniazid may increase the hepatotoxicity of acetaminophen.
Documented hypersensitivity
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Caution in patients who are dependent on opiates, because this substitution may result in acute opiate-withdrawal symptoms; caution in the presence of severe renal or hepatic dysfunction.
Hepatotoxicity with acetaminophen is possible in individuals with chronic alcoholism following various dose levels; severe or recurrent pain or high or continued fever may indicate a serious illness; acetaminophen is contained in many OTC products, and combined use with these products may result in cumulative acetaminophen doses and exceed recommended the maximum dose.
NSAIDs have analgesic, anti-inflammatory, and antipyretic activities. Their mechanism of action is not known, but they may inhibit cyclooxygenase activity and prostaglandin synthesis. Other mechanisms may also exist, such as leukotriene synthesis inhibition, lysosomal enzyme release, lipoxygenase activity, neutrophil aggregation, and various cell membrane functions. During rehabilitation, shoulder discomfort may interfere with sleep or basic ADLs. Oral NSAIDs should decrease the discomfort. NSAIDs do not speed recovery and should not be used to accelerate physical therapy goals.
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Toxicity, Nonsteroidal Anti-inflammatory Agents
DOC for mild to moderate pain. Inhibits inflammatory reactions and pain by decreasing prostaglandin synthesis.
200-400 mg PO q4-6h while symptoms persist; not to exceed 3.2 g/d
<6 months: Not established
6 months to 12 years: 4-10 mg/kg/dose PO tid/qid
>12 years: Administer as in adults.
Coadministration with aspirin increases the risk of inducing serious NSAID-related adverse effects; probenecid may increase the concentrations and, possibly, the toxicity of NSAIDs; may decrease the effect of hydralazine, captopril, and beta-blockers; may decrease the diuretic effects of furosemide and thiazides; may increase PT duration when taking anticoagulants (instruct patients to watch for signs of bleeding); may increase the risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently
Documented hypersensitivity; peptic ulcer disease, recent GI bleeding or perforation, renal insufficiency, or high risk of bleeding
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus
Caution in patients with congestive heart failure, hypertension, and decreased renal and hepatic function; caution in the presence of coagulation abnormalities or during anticoagulant therapy
For mild to moderate pain. Inhibits inflammatory reactions and pain by decreasing the activity of cyclooxygenase, which results in a decrease of prostaglandin synthesis.
500 mg PO followed by 250 mg q6-8h; not to exceed 1.25 g/d
<2 years: Not established
>2 years: 2.5 mg/kg/dose PO; not to exceed 10 mg/kg/d
Coadministration with aspirin increases the risk of inducing serious NSAID-related adverse effects; probenecid may increase the concentrations and, possibly, the toxicity of NSAIDs; may decrease the effect of hydralazine, captopril, and beta-blockers; may decrease the diuretic effects of furosemide and thiazides; may increase PT duration when taking anticoagulants (instruct patients to watch for signs of bleeding); may increase the risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently
Documented hypersensitivity; peptic ulcer disease; recent GI bleeding or perforation; renal insufficiency
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus
Acute renal insufficiency, interstitial nephritis, hyperkalemia, hyponatremia, and renal papillary necrosis may occur; patients with preexisting renal disease or compromised renal perfusion risk acute renal failure; leukopenia occurs rarely, is transient, and usually returns to normal during therapy; persistent leukopenia, granulocytopenia, or thrombocytopenia warrants further evaluation and may require discontinuation of the drug.
For mild to moderate pain and inflammation. Small initial doses are indicated in small and elderly patients and in those with renal or liver disease.
Doses >75 mg do not increase the therapeutic effects. Administer high doses with caution and closely observe the patient for response.
25-50 mg PO q6-8h prn; not to exceed 300 mg/d
<3 months: Not established
3 months to 12 years: 0.1-1 mg/kg PO q6-8h
>12 years: Administer as in adults.
Coadministration with aspirin increases the risk of inducing serious NSAID-related adverse effects; probenecid may increase the concentrations and, possibly, the toxicity of NSAIDs; may decrease the effect of hydralazine, captopril, and beta-blockers; may decrease the diuretic effects of furosemide and thiazides; may increase PT duration when taking anticoagulants (instruct patients to watch for signs of bleeding); may increase the risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently
Documented hypersensitivity
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus
Caution in patients with congestive heart failure, hypertension, and decreased renal and hepatic function; caution in the presence of coagulation abnormalities or during anticoagulant therapy
Return to play in patients following a shoulder dislocation is determined when full ROM and strength have been regained. Return to play is usually sooner for older adults than for younger athletes, because the fear of redislocation is much lower in older adults. Usually, older adults can return to play within 3 months. With younger adults, conditioning can continue through shoulder rehabilitation; however, decisions about returning to play should be more conservative than those in older adults. Again, absolute criteria are full ROM and full strength.
When determining a patient's return to competitive sports, the author uses the following criteria:
The most common complication of an acute shoulder dislocation is recurrence. This complication occurs because the capsule and surrounding ligaments are stretched and deformed during the dislocation. Age is the most important indicator for prognosis; dislocations recur in approximately 90% of teenagers.
Another common complication following dislocation is fracture. The most common type is a Hill-Sachs lesion or compression fracture of the posterior humeral head. Fractures of the proximal humerus, greater tuberosity, coracoid, and acromion have also been described.
Rotator cuff tears also commonly occur as a result of shoulder dislocations, and the frequency of this complication increases with age. This complication can be expected in 30-35% of patients aged 40 years or older. Slow progression in return to active function following shoulder dislocation in a middle-aged patient should warrant a workup for a rotator cuff tear.
Vascular injuries are rare, but they do occur, especially in older patients. Vascular injuries are more common with inferior dislocations and usually involve a branch of the axillary artery.
Nerve injuries are much more common than vascular injuries, especially with anterior or inferior dislocations. The axillary nerve is the nerve injured most often and may be crushed between the humeral head and the axillary border of the scapula or injured by traction from the humeral head. Axillary nerve injury has been reported in as many as 33% of acute anterior dislocations.
Age at dislocation is the most important prognostic indicator for recurrence of shoulder dislocations. Younger age at initial injury increases the likelihood for future dislocation. The recurrence rate is thought to be 90% if the initial episode occurs in the teen years. In patients aged 40 years or older, the recurrence rate is 10-15%. Most redislocations occur within 2 years of the primary injury. Persons with axillary nerve injuries can be expected to recover completely within 3-6 months.
Educate the patient on the importance of strength training following shoulder dislocation. The patient must understand that recurrence is possible and therapy should be used to prevent recurrence.
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Jouve F, Graveleau N, Nove-Josserand L, Walch G. [Recurrent anterior instability of the shoulder associated with full thickness rotator cuff tear: results of surgical treatment] [French]. Rev Chir Orthop Reparatrice Appar Mot. Nov 2008;94(7):659-69. [Medline].
Pouliart N, Gagey O. Consequences of a Perthes-Bankart lesion in twenty cadaver shoulders. J Shoulder Elbow Surg. Nov-Dec 2008;17(6):981-5. [Medline].
Reeves B. Acute anterior dislocation of the shoulder. Clinical and experimental studies. Ann R Coll Surg Engl. May 1969;44(5):255-73. [Medline]. [Full Text].
shoulder dislocation, dislocated shoulder, shoulder pain, rotator cuff muscles, shoulder injury, anterior shoulder dislocation, dislocation of the glenohumeral joint, glenohumeral dislocation, glenohumeral subluxation, glenohumeral joint dislocation, posterior shoulder dislocation, acromioclavicular joint injury, humerus, glenoid, glenohumeral ligaments, glenoid labrum, negative intra-articular pressure
L. Edward Seade, MD, Chief of Shoulder Service, Orthopaedic Specialists of Austin
Disclosure: Nothing to disclose.
Robert Josey, MD, Consulting Staff, Department of Orthopedic Surgery, Orthopaedic Specialists of Austin
Robert Josey, MD is a member of the following medical societies: American Medical Association, Phi Beta Kappa, and Texas Medical Association
Disclosure: Nothing to disclose.
Joseph P Garry, MD, Director of Sports Medicine and Sports Medicine Fellowship, Associate Professor of Family Medicine and Exercise and Sport Science, Department of Family Medicine, East Carolina University Brody School of Medicine
Joseph P Garry, MD is a member of the following medical societies: American Academy of Family Physicians, American College of Sports Medicine, American Heart Association, American Medical Society for Sports Medicine, North American Primary Care Research Group, and North Carolina Medical Society
Disclosure: Nothing to disclose.
Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: Nothing to disclose.
Henry T Goitz, MD, Fellowship Director, Sports Medicine, Department of Orthopedic Surgery, Henry Ford Hospital
Henry T Goitz, MD is a member of the following medical societies: American Academy of Orthopaedic Surgeons and American Orthopaedic Society for Sports Medicine
Disclosure: Nothing to disclose.
Jon B Whitehurst, MD, Clinical Instructor of Surgery, University of Illinois College of Medicine; Partner and Executive Board Member, Rockford Orthopedic Associates; Orthopedic Chairman, Rockford Memorial Hospital
Jon B Whitehurst, MD is a member of the following medical societies: American Academy of Orthopaedic Surgeons, American Orthopaedic Society for Sports Medicine, and Arthroscopy Association of North America
Disclosure: Nothing to disclose.
Craig C Young, MD, Professor, Departments of Orthopedic Surgery and Community and Family Medicine, Medical Director of Sports Medicine, Sports Medicine Fellowship Director, Medical College of Wisconsin
Craig C Young, MD is a member of the following medical societies: American Academy of Family Physicians, American College of Sports Medicine, American Medical Society for Sports Medicine, Phi Beta Kappa, and Wilderness Medical Society
Disclosure: Nothing to disclose.
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