3-70
NOTE: Although it is possible to reduce a patellar dislocation by simply “pushing” the patella back into the origi-
nal position, resist the temptation— it may cause cartilage damage and it is unnecessarily painful for patients.
Symptom: Joint Pain: Shoulder Pain
CDR Scott Flinn, MC, USNIntroduction: The shoulder is an inherently unstable, complex and intricate joint that can be injured through
trauma or overuse. A good history and physical will guide most proper initial management. Shoulder
pain is usually due to one of the four main groups of shoulder structures; the muscles, the bones and
acromioclavicular (AC) joint, and the glenohumeral joint.
Shoulder pain may also be referred from a neck injury, such as nerve impingement, heart problems, such
as a heart attack or pericarditis, and lung problems such as a pneumothorax. Diagnostic differentiation is
often difficult. Some of these entities and clinical syndromes represent primary disorders of the cervicobrachial
region; others are local manifestations of systemic disease.
Risk Factors: Patients with “loose joints” may have more intrinsic motion in the glenohumeral joint, known as
multidirectional instability (MDI). MDI predisposes people to certain injuries such as shoulder dislocations,
subluxations, and impingement syndrome. A young, otherwise healthy active person who traumatically suffers
an anterior dislocation has roughly an 80% chance of recurrence.
Subjective: Symptoms
Acute shoulder pain (immediate onset) is usually due to a recent traumatic cause.
Chronic or recurrent intermittent pain is usually due to overuse syndromes or the sequelae of recurrent trauma.
Constitutional
If there is night pain, think of rotator cuff injury, or, rarely, tumors.
Fever and chills may be present in the rare case of septic shoulder joints. If there is diaphoresis, shortness
of breath, and pain in the left shoulder, consider an acute myocardial infarction, neoplasm, or lung injury.
Numbness or tingling suggests referred nerve impingement pain.
Location
AC joint injury presents with pain at/over the A/C joint. A rotator cuff impingement or tear produces deep
pain in the anterior shoulder. Fractures produce pain that may be hard to localize but, is aggravated with
movement. Shoulder dislocations usually present with obvious deformity and severe pain. Subluxations and
labrum (cartilaginous ring around glenoid fossa) tears produce a less intense but deep, aching pain and a
painful click.
Focused History: Was there an acute injury? (trauma suggests dislocation, subluxation, muscle tear or
fracture). Is the pain worse with overhead motion and at night? (This suggests impingement syndrome).
Is there numbness, tingling, or weakness? (This is consistent with a nerve impingement). Can the arm be
moved? (If not, the possibility of fracture or dislocation is very high). Is there a painful, reproducible click?
(Clicks that are associated with pain suggest a labrum tear).
Objective: Signs
Using Basic Tools
Inspection: Look for obvious deformity, suggesting a fracture or dislocation. An anterior dislocation will have a
prominent acromial process as the humeral head has slipped inferiorly and anteriorly out of the glenohumeral
joint. Erythema and edema may be the result of a contusion or fracture. A prominent clavicle may be the
result of an AC separation or clavicle fracture. Have the patient attempt to touch their opposite shoulder with
the affected arm. If they are unable to do so, think anterior shoulder dislocation or fracture.
Auscultation: A painful click may represent a labrum tear or a loose body in the joint.
Palpation: Palpate for edema from contusions or fractures. Feel along the clavicle from midline to the AC joint
for obvious deformity or crepitus from a clavicle fracture. Feel the AC joint for point tenderness or deformity. If
acute, tenderness may represent an AC joint separation, if chronic it could be due to AC joint capsulitis. Check
sensation on the lateral deltoid (axillary nerve root, C5 nerve root). Check shoulder strength for internal and
external rotation, abduction, and in the “empty can” position (thumb down at about six or seven o’clock) to
check the rotator cuff muscles. This sign is positive in rotator cuff tendonitis (impingement syndrome).