BASICS
DESCRIPTION
- Shoulder pain is common and affects patients of all ages. Causes include acute trauma or overuse during sports and activities of everyday living.
- Age plays an important role in determining the etiology of shoulder pain.
- Onset and characteristics of pain, weakness, mechanism of injury, and functional limitation help guide an accurate diagnose.
EPIDEMIOLOGY
- Shoulder pain accounts for 16% of all musculoskeletal complaints.
- The lifetime prevalence of shoulder pain is ¢ ¼70%.
- Predominant etiology varies with age:
- <30 years: shoulder instability
- >30 years: rotator cuff (RTC) disorder
- 30 to 50 years: tendinopathy
- 40 to 60 years: partial tear
- >60 years: full-thickness tear
- >60 years: glenohumeral osteoarthritis (OA)
Incidence
The incidence of shoulder pain is 7 to 25 cases/1,000 patients, with a peak incidence in the 4th to 6th decades.
ETIOLOGY AND PATHOPHYSIOLOGY
Pathology varies with cause:
- Trauma (fracture, dislocation, ligament/tendon tear, acromioclavicular [AC] separation)
- Overuse (RTC pathology, biceps tenosynovitis, bursitis, muscle strain, apophyseal injuries)
- RTC disorders most commonly result from repetitive overhead activity, leading to RTC impingement with a 3 stage progression:
- Stage I: tendinopathy
- Stage II: partial RTC tear
- Stage III: full-thickness RTC tear
- Subacromial bursitis can occur with RTC disorders but is rarely an isolated diagnosis.
- Age-related: AC and glenohumeral joint OA, adhesive capsulitis, RTC tear with increasing age; pediatric athletes instability and physeal injuries are more common.
- Rheumatologic (rheumatoid arthritis, polymyalgia rheumatica, fibromyalgia)
- Referred pain (neck, gallbladder)
RISK FACTORS
- Repetitive overhead activity
- Overhead and upper extremity weight-bearing sports (baseball, softball, swimming, tennis, volleyball)
- Weight lifting: AC disorders
- Rapid increases in training frequency or load (often associated with improper technique)
- Muscle weakness or imbalance
- Trauma or fall onto the shoulder
- Diabetes, thyroid disorders, female gender, and age 40 to 60 years are risk factors for adhesive capsulitis.
GENERAL PREVENTION
- Maintain strength and range of motion (ROM).
- Avoid repetitive overhead activities (pitch counts).
- Proper technique (pitching, weight lifting)
DIAGNOSIS
HISTORY
- Pain characteristics
- Superior shoulder pain: AC pathology, trapezius strain
- Lateral/deltoid pain: RTC pathology (RTC pain typically does not extend past elbow.)
- Diffuse pain: RTC pathology, adhesive capsulitis, glenohumeral OA
- Posterior (scapular) pain: scapulothoracic dyskinesis
- Night pain: RTC pathology (pain laying on affected side), adhesive capsulitis, glenohumeral OA
- Stiff shoulder: adhesive capsulitis
- Pain with cross-body activities: AC pathology
- Pain with abduction/external rotation (reaching behind): shoulder instability
- Pain with overhead activity: RTC pathology, AC pathology, labrum pathology
- Pain with turning neck, pain past elbow: cervical pathology
- Mechanism of injury
- Fall on outstretched hand: traumatic shoulder instability/dislocation
- Fall directly onto shoulder: AC joint sprain, clavicular fracture
- Repetitive overhead activity: RTC pathology
- Age
- Shoulder instability (subluxation, dislocation, multidirectional instability) is the most common cause of shoulder pain in young athletes (<30 years old).
- RTC disorders are the most common cause of shoulder pain in patients >30 years old. Severity of RTC disorder increases with age.
- Older patients (>60 years old) commonly have OA.
- Trauma in a young person <40 years is more commonly associated with dislocation/subluxation. In patients >40 years, trauma is more commonly associated with RTC tear.
PHYSICAL EXAM
- Observe face and shoulder movements as patient disrobes, moves arm, and shakes hand.
- Inspect for malalignment, muscle atrophy, asymmetry, erythema, ecchymosis and swelling. Scapular winging suggests long thoracic nerve or muscular (trapezius, serratus anterior) dysfunction. Prominent scapular spine with scalloped infraspinatus fossa suggests infraspinatus atrophy.
- Palpate for tenderness, warmth, bony step-offs.
- Evaluate active and passive ROM and flexibility:
- Decreased active AND passive ROM are more common with adhesive capsulitis.
- Mildly decreased active and/or passive ROM may also indicate glenohumeral OA.
- Decreased active, full passive ROM: RTC pathology
- Evaluate for muscle strength including grip, biceps, triceps, and deltoid. Test RTC strength: supraspinatus (empty can test), infraspinatus/teres minor (resisted external rotation, external lag test), subscapularis (lift-off test, belly press, resisted internal rotation). Pain with RTC strength testing indicates RTC pathology. Weakness could suggest tear.
- Special tests
- Neer, Hawkin tests: RTC impingement
- Drop-arm test: RTC tear
- Cross-arm adduction test: AC joint arthritis
- Speed, Yergason tests: biceps tendinopathy
- Apprehension, relocation test: anterior glenohumeral joint instability
- Sulcus sign: inferior glenohumeral joint instability
- O 'Brien, clunk test: labral pathology
- Spurling test: cervical pathology
DIFFERENTIAL DIAGNOSIS
- Fracture (clavicle, humerus, scapula), contusion
- RTC disorder: impingement, tear, calcific tendonitis
- Subacromial bursitis
- Scapulothoracic dyskinesis
- AC joint pathology (AC separation/OA, osteolysis)
- Biceps tenosynovitis or tear
- Acromial apophysitis or os acromiale
- Glenohumeral joint OA
- Glenohumeral joint instability (acute dislocation or chronic multidirectional instability)
- Adhesive capsulitis
- Labral tear or associated bony pathology
- Muscle strain (trapezius, deltoid, biceps)
- Cervical radiculopathy
- Other: autoimmune, rheumatologic, referred pain, septic joint (biliary/splenic, cardiac, pneumonia/lung mass)
DIAGNOSTIC TESTS & INTERPRETATION
- Shoulder pain can be accurately diagnosed with a careful history and physical exam:
- Adults with nontraumatic shoulder pain of <4 weeks duration may not require initial imaging.
- History of significant trauma, prolonged symptoms, or red flags (older age, fever, rest pain) suggest need for imaging.
- Plain radiographs are first-line:
- Assess for fracture, degenerative changes, signs of dislocation (Bankart, Hill-Sachs deformity), signs of large RTC tear (sclerosis, proximal migration of humeral head), anatomic deformities contributing to impingement, and occult tumor.
- Standard views: anteroposterior, scapular Y, axillary
- EMG study of the upper extremity may help differentiate referred cervical pain from a primary shoulder disorder.
- Obtain ECG if any suspicion for cardiac etiology.
- Serologic tests if autoimmune etiology is suspected.
Follow-Up Tests & Special Considerations
- CT scan can rule out occult fracture.
- MRI is gold standard for noninvasive soft tissue imaging, including RTC, biceps tendon.
- MR arthrogram may be necessary to assess for labral tears or small/partial RTC tears.
- Ultrasound (US) helps assess RTC tears, biceps tendinopathies, and AC joint disorders.
Diagnostic Procedures/Other
Diagnostic arthroscopy after noninterventional means have been exhausted if structural injury is suspected.
Test Interpretation
Depends on underlying diagnosis
- Tendinosis rather than tendonitis is common with stage I impingement.
- Capsular scarring is the hallmark of adhesive capsulitis.
- RTC tendon calcifications with calcific tendonitis
TREATMENT
Treatment is based on underlying diagnosis. In general, conservative therapy includes activity modification, analgesics, and/or anti-inflammatory medicines in association with appropriate rehabilitative programs.
MEDICATION
First Line
- Analgesics and anti-inflammatory medications for symptomatic relief:
- Ibuprofen: 200 to 800 mg TID
- Naproxen: 250 to 500 mg BID
- Acetaminophen: not to exceed 3 g/day
- Corticosteroid injections (subacromial, glenohumeral, AC, subscapular bursa) acutely relieve pain due to RTC pathology, adhesive capsulitis, OA, or scapulothoracic dyskinesis (1)[A]. This improves ability to engage in rehabilitative activities.
- US guidance improves accuracy of anatomic placement of corticosteroid injections (2)[A].
ISSUES FOR REFERRAL
Refer if etiology remains unclear, patient is not responsive to conservative care, for complicated or displaced fractures, or full thickness RTC tears >1 cm acute or chronic in patients <65 years old or any tear with significant changes in functional status. These tears have a high rate of progression, fatty infiltration, or retraction with nonoperative care (3).
ADDITIONAL THERAPIES
- Physical therapy benefits persistent RTC disorders, adhesive capsulitis, and shoulder instability.
- Physical therapy/exercise may improve nonspecific shoulder pain, but it does not generally improve ROM or function (4)[A].
- Manual manipulative therapy (MMT) by chiropractors, osteopathic physicians, or physical therapists improves pain with adhesive capsulitis, RTC, and soft tissue disorders. (5)[A] MMT is generally less effective than glucocorticoid injections at 6 weeks with similar long-term outcomes in adhesive capsulitis. (6)[A].
SURGERY/OTHER PROCEDURES
- Surgery is necessary for shoulder pain caused by acute displaced fractures, large RTC tears (criteria as above), shoulder dislocation in patients <20 years of age. Surgery may be necessary for shoulder pain unresponsive to conservative measures >3 to 6 months. Surgery is not more effective than active nonsurgical treatment in impingement syndrome (7)[A].
- Platelet-rich therapies need more conclusive evidence before routine use in treatment of MSK soft tissue injuries (8)[A].
COMPLEMENTARY & ALTERNATIVE MEDICINE
Acupuncture may help with acute shoulder pain. There is no conclusive evidence for the effectiveness of acupuncture.
ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
Limit overhead activity to reduce impingement symptoms.
PATIENT EDUCATION
Refer to specific diagnosis for shoulder pain.
PROGNOSIS
Shoulder pain generally has a favorable outcome with conservative care, but recovery can be slow, with 40 " 50% of patients complaining of persistent pain or recurrence at 12 months.
REFERENCES
11 Gross C, Dhawan A, Harwood D, et al. Glenohumeral joint injections: a review. Sports Health. 2013;(5)2:153 " 159.22 Soh E, Li W, Ong KO, et al. Image-guided versus blind corticosteroid injections in adults with shoulder pain: a systematic review. BMC Musculoskelet Disord. 2011;12:137.33 Armstrong A. Evaluation and management of adult shoulder pain: a focus on rotator cuff disorders, acromioclavicular joint arthritis, and glenohumeral arthritis. Med Clin North Am. 2014;98(4):755 " 775.44 van den Dolder PA, Ferreira PH, Refshauge KM. Effectiveness of soft tissue massage and exercise for the treatment of non-specific shoulder pain: a systematic review with meta-analysis. Br J Sports Med. 2014;48(16):1216 " 1226.55 Brantingham JW, Cassa TK, Bonnefin D, et al. Manipulative therapy for shoulder pain and disorders: expansion of a systematic review. J Manipulative Physiol Ther. 2011;34(5):314 " 346.66 Page MJ, Green S, Kramer S, et al. Manual therapy and exercise for adhesive capsulitis (frozen shoulder). Cochrane Database Syst Rev. 2014;(8):CD011275.77 Coghlan JA, Buchbinder R, Green S, et al. Surgery for rotator cuff disease. Cochrane Database Syst Rev. 2008;(1):CD005619.88 Moraes VY, Lenza M, Tamaoki MJ, et al. Platelet-rich therapies for musculoskeletal soft tissue injuries. Cochrane Database Syst Rev. 2014;(4):CD010071.
ADDITIONAL READING
- Cadogan A, Laslett M, Hing WA, et al. A prospective study of shoulder pain in primary care: prevalence of imaged pathology and response to guided diagnostic blocks. BMC Musculoskelet Disord. 2011;12:119.
- Celik D, Sirmen B, Demirhan M. The relationship of muscle strength and pain in subacromial impingement. Acta Orthop Traumatol Turc. 2011;45(2):79 " 84.
- Littlewood C, Ashton J, Chance-Larsen K, et al. Exercise for rotator cuff tendinopathy: a systematic review. Physiotherapy. 2012;98(2):101 " 109.
- Sipola P, Niemitukia L, Kr ¶r H, et al. Detection and quantification of rotator cuff tears with ultrasonography and magnetic resonance imaging " a prospective study in 77 consecutive patients with a surgical reference. Ultrasound Med Biol. 2010;36(12):1981 " 1989.
CODES
ICD10
- M25.519 Pain in unspecified shoulder
- S43.429A Sprain of unspecified rotator cuff capsule, init encntr
- M19.019 Primary osteoarthritis, unspecified shoulder
- M75.00 Adhesive capsulitis of unspecified shoulder
- M25.511 Pain in right shoulder
- M75.82 Other shoulder lesions, left shoulder
- M25.512 Pain in left shoulder
- M75.80 Other shoulder lesions, unspecified shoulder
- M75.81 Other shoulder lesions, right shoulder
- M24.819 Oth specific joint derangements of unsp shoulder, NEC
ICD9
- 719.41 Pain in joint, shoulder region
- 840.4 Rotator cuff (capsule) sprain
- 715.91 Osteoarthrosis, unspecified whether generalized or localized, shoulder region
- 726.0 Adhesive capsulitis of shoulder
- 726.19 Other specified disorders of bursae and tendons in shoulder region
- 718.81 Other joint derangement, not elsewhere classified, shoulder region
SNOMED
- 45326000 Shoulder pain (finding)
- 414033006 Disorder of rotator cuff
- 67315001 degenerative joint disease of shoulder region (disorder)
- 399114005 adhesive capsulitis of shoulder (disorder)
- 442520000 inflammation of rotator cuff tendon (disorder)
- 267949000 Shoulder joint pain (finding)
- 12247771000119104 Bilateral shoulder joint pain (disorder)
CLINICAL PEARLS
- RTC disorders (tendinopathy, tears) are the most common cause of shoulder pain in individuals >30 years of age.
- Shoulder instability (acute dislocation/subluxation or chronic instability) is the most common source of shoulder pain in individuals <30 years of age.
- Patients with diabetes are at increased risk for adhesive capsulitis.