MSK Office Mix Flashcards
Shoulder parts
3 bones in the girdle: clavicle, scapula, proximal humerus
4 articular surfaces: glenohumeral, sternoclavicular, acromioclavicular, scapulothoracic
5 main muscles:
deltoid: abduction (after 90)
supraspinatus: abduction (to 90)
infraspinatus: external rotation
subscapularis: internal rotation
teres minor: external rotation
(last 4 are rotator cuff)
shoulder Injury potential: Intrinsic
Glenohumeral ligaments: bone to bone; sprain or tear
Muscle or tendon inflammation, tear, strain: rotator cuff, deltoid
Bones: fracture, inflamed capsule
Pain is referred to should er from
Neuro: Cranial nerve root compression (C5, C6), supraspinatus nerve compression, brachial plexus lesions, herpes zoster, spinal cord lesion, cervical spine disease
Abdominal: hepatobiliary disease, diaphragmatic irritation (e.g. splenic injury, ruptured ectopic pregnancy, perforated viscus)
CV: MI, axillary vein thrombosis, thoracic outlet syndrome
Thoracic: upper lobe pneumonia, apical lung tumor, pulmonary embolus
Pain tends to be more poorly localized and since it is referred pain, reproduction of their pain should be none or minimal at best.
NO MATTER the extrinsic cause of the referred pain, non-reproduction of pain with palpation or maneuvers must trigger consideration of causes outside the shoulder
Common Intrinsic Pathology of Shoulder:
Impingement Tendinopathy Tendon tear Acromioclavicular separation Osteoarthritis Adhesive capsulitis Bursitis Instability SLAP lesion
Common presenting complaints (shoulder)
Pain with specific movement or palpation Stiffness Weakness/loss of function - Atrophy - Pain Instability Combination of above
Shoulder exam
Inspection Palpation Bilaterally: always examine the pain ? Reproduce their pain ? Find new tenderness ROM Nervous system screening as appropriate to ddx Strength Special testing
shoulder Work up:
X-ray in traumatic etiology
Ultrasound very helpful in experienced hands
MRI
Arthrography: contrast injection into joint with serial x-rays or fluoroscopy largely replaced by MRI
Shoulder strength
supraspinatus: pt abducts 90 degree arm against resistance. Or empty can test
subscapularis- lift off or pt rotates bent arm medially against resistance
infraspinatus, teres minor: pt rotates bent arm laterally against resistance
Weakness of the rotator cuff can lead to
superior subluxation of the humeral head when the shoulder is abducted beyond 90 degrees, predisposing to and helping to identify impingement syndromes. Surgical treatment options often necessary for satisfactory results.
Impingement
can cause a rotator cuff tear
Signs/ Tests?
. Night pain common, gradual onset. Atrophy of superior and posterior muscles possible. Localized tenderness not common, but pain, crepitus or sudden pain while abducting the arm common. Supraspinatus most often involved. Test: Hawkins and Near impingement signs, followed by special test for supraspinatus for best evidence of diagnosis.
what do we see in x-ray of arthritis?
loss of joint space, bone spur
risk factor for adhesive capsulitis
DM
tendonitis vs bursitis
Tender,
good clue between bursa and tendonitis is pain difference with active vs passive ROM.
injection test for shoulder pain
Patients with a rotator cuff tear will have persistent weakness despite pain relief with injection, while those with rotator cuff tendonopathy will have normal strength in association with pain relief. Patients with a frozen shoulder will have persistent loss of range of motion. Dramatic reduction in pain and improvement in overall shoulder function after injection of the subacromial bursa effectively rules out a significant glenohumeral joint process.
The lidocaine injection test in the subacromial bursa is indicated when the history and physical examination cannot effectively exclude an underlying rotator cuff tendon tear, a developing frozen shoulder, or concurrent involvement of the acromioclavicular (AC) joint.
SLAP Lesion:
Superior Labrum Anterior (to) Posterior
