Shoulder Pain Differential Diagnosis

Impingement (tendinopathy, bursitis, PASTA)

• Age usually 35-55; if younger and really looks like impingement, think instability
  
  
• Overhead work or play (tennis, pitching)
  
  
• Pain rolling on shoulder in bed/ night pain

• Needs FROM to exclude dx of concomitant frozen shoulder
  
  
• Positive impingement sign(s)
  
  
• Assess ER strength to exclude posterior cuff tear

• Plain films exclude DJD
  
  
• Plain films showing big spur
  
  
• MRI exclude full-thickness tear (Note: Pre-test probability of tendinopathy is very high, so that alone on MRI is not really meaningful)

• Weakness may be due to pain or torn tendon
  
  

Full-thickness rotator cuff tears

• Age usually a bit older than impingement
  
  
• Pain rolling on shoulder in bed/night pain
  
  
• Weakness
  
  
• Lateral arm pain, near deltoid insertion, but does not radiate below elbow

• Passive motion typically greater than active motion
  
  
• Decreased strength in elevation, abduction,
  
  
• Drop arm

• Plain films exclude DJD
  
  
• MRI to document extent of tear
  
  
• MRI to assess repairability of the tear (look at muscle atrophy on T1 oblique sagittal sequence)
  
  

• Some people have no problem despite full tears

Suprascapular neuropathy

• Presents like impingement
• Constant, unrelenting pain

• Examines like cuff tear but has atrophy of supra- and infraspinatus (NOT SEEN THROUGH A SHIRT!)

• MRI can be pretty normal, except for atrophy (muscle atrophy in setting of intact tendons)

• EMG needed

Multi-directional instability

• History of dislocation, subluxation
  
  
• Other joints lax
  
  
• May present with impingement symptoms

• Sulcus sign
  
  
• Laxity in other joints
  
  
• Apprehension sign
  
  
• +/- Scapular dyskinesia/ weakness

• Patulous capsule
  
  
• Often normal labrum/rotator cuff

• Psych overlap?

Uni-directional instability – anterior

• History of dislocation with or without need for manual reduction
  
  
• Usually younger patients

• + Apprehension sign
  
  
• + Relocation test
  
  
• Pain in abduction/external rotation with Bankart lesion

• If acute, MRI may be diagnostic (MRI arthrogram increases sensitivity/specificity in chronic cases)
  
  
• Plain radiographs help to exclude bone lesions (Bankart/Hill Sachs)
  
  
• CT may help evaluate osseous structures if bone deficiency is suspected

• Acute "dislocation" should refer to only confirmed cases requiring relocation

Uni-directional Instability – Posterior

• May present with multi-directional instability
  
  
• Posterior shoulder pain
  
  
• May have history of dislocation, more likely recurrent posterior subluxation (RPS)
  
  
• May be seen with seizures/ electrocution

• Pain with jerk test
  
  
• +/- Kim test
  
  
• Pain with adduction and internal rotation

• MRI with or without arthrogram is helpful to evaluate posterior labrum
  
  
• Radiographs/CT scan can evaluate for glenoid/humeral retroversion

Labral/SLAP tears

• May have traumatic origin (distraction injury)
  
  
• History of repetitive trauma (throwing motion, overhead athletes)
  
  
• May be associated with instability of the glenohumeral joint

• + Mayo Shear Test (Dynamic labral shear)
  
  
• + O’Brien’s test

• MRI demonstrates detachment or tear of the superior labrum at the biceps anchor
  
  
• MRI arthrogram may help in indeterminate cases

• SLAP and pain may both be present but not causally related
• Evaluate and manage posterior capsule tightness

Paralabral cyst

• Typically presents with deep seated shoulder pain
  
  
• Weakness in external rotation may be present

• May have provocative SLAP tests (O’Brien’s, Mayo Shear test)
  
  
• Atrophy of infraspinatus

• MRI helps determine the size of cyst and impingement of spinoglenoid notch

Biceps tendinopathy

• Anterior shoulder pain
  
  
• May also have pain with supination

• Tenderness to palpation over tendon in bicipital groove
  
  
• Speed’s test
  
  
• O’Brien’s test

• Typically a clinical diagnosis as imaging may be normal

Proximal biceps ruptures or subluxation

• Pop

• Popeye deformity
  
  
• May be associated with subscapularis tears

• MRI helps to determine status of the rotator cuff and subscapularis which can be associated with this diagnosis

AC arthropathy (including old fractures)

• History of AC separation or distal clavicle fx
  
  
• Weight lifter

• May have prominent distal clavicle or large AC joint
  
  
• Tenderness on ac joint
  
  
• Pain with x-body adduction
• Bell-van Riet test
  
  
• Relief from injection

• Arthrosis
  
  
• Osteolysis
  
  
• Evidence of old fx or separation
  
  
• Plain radiographs or MRI are diagnostic

AC instability

• Anterior shoulder pain after a direct fall or contusion to the shoulder

• Clinical evidence of elevated clavicle relative to acromion
  
  
• May have posterior subluxation with cross body adduction

• Stress radiographs are helpful in subtle cases
  
  
• Evaluation of the coraco-clavicular distance (compare to contralateral side)

Os acromiale

• Pain over anterior shoulder
  
  
• May be present after fall or direct contusion

• Tenderness over acromion

• Axial cuts of MRI best to see

Glenohumeral joint DJD

• Older patient
  
  
• Typical arthritis complaints

• Decreased motion
  
  
• May have weakness secondary to pain

• Goat’s beard on x-ray
  
  
• Joint space narrowing less common than in lower extremity DJD (ie, can’t have a "standing" film of arm)

Humeral OCD

• Presents like DJD ??
  
  
• May have vague complaints (achy pain)
  
  
• May present with instability symptoms

• Maybe no findings

• Seen on MRI, CT

Gout, etc. (inflammatory arthritides)

• Presents like DJD
  
  
• Pain can be at rest especially with infection (which is very rare in normal host)

• Presents like DJD
  
  
• Micromotion pain rare, but seen in gout (presents like infection)

• Absence of osteophytes is classic presentation on x-rays
  
  
• Decreased joint space and sclerosis is primary finding

Scapulo-thoracic dyskinesis

• Achiness in shoulder, decreased velocity in throwing

• Must have patient remove shirt and observe scapula from back
  
  
• SICK scapula findings (dyskinesia, infera, etc.)

• Clinical examination is key
  
  
• Radiographs, MRI may be normal

Long thoracic nerve palsy

• Weakness, diffuse shoulder pain
  
  
• May be present after viral illness

• Winging on wall-pushup

• Radiographs may show abnormal position of scapula (chest xray)

Bone tumor

• Pain can be at rest

Humeral head AVN

• Pain can be at rest
  
  
• May present like DJD

• Restriction in range of motion and pain

• Seen on MRI

Syrynx

• Presents like AVN—it’s a "neuropathic arthropathy"

• Loss of shoulder range of motion
  
  
• Painless range of motion – less pain than expected based on amount of destruction

• MRI of neck
  
  
• Radiographs of shoulder show Charcot arthropathy of the joint

Parsonage Turner Syndrome

• Burning pain
  
  
• Weakness
  
  
• May be post-viral

• Atrophy of supra/infraspipnatus may be present
  
  
• Weakness on external rotation testing

• MRI helps to evaluate the muscle and rule out rotator cuff pathology
  
  
• Consider MRI of brachial plexus or EMG

Radiculopathy

• Radiating pain, respecting dermatomal borders

• Decreased/painful range of motion of the neck
  
  
• Sensory disturbance along dermatome
  
  
• Radiation below elbow

• MRI of the cervical spine evaluates for disc herniation/compression of the nerve root

Malingering

• In litigation
  
  
• Wears sunglasses during exam despite no recent eye surgery
  
  

• Active motion better than passive motion
  
  
• Elevates arm less than would be possible after arthrodesis
• Resistance against passive range of motion

• Radiographs, MRI typically normal or non-specific to clinical examination

Lung cancer

• Smart alecks will tell you that a smoking history should be enough, but too many people smoke for that to be useful. Chronic cough, weight loss, cachexia may be more specific

• Overall assessment of the patient, Horner’s syndrome

• Apical tumor seen on x-ray of the shoulder