CONDITIONS OF THE SHOULDER Flashcards
Describe Winging of the scapula
-Damage to the long thoracic nerve paralyses the serratus anterior which normally holds the scapula against ribcage.
-Medial border of the scapula is no longer held against the chest wall so protrudes posteriorly.
What are causes of winged scapula?
-Trauma
-Long thoracic nerve is vunerbale to surgical trauma during mastectomy.
(passes superficial to serratus anterior muscle in the medial wall of the axilla)
-Blunt trauma to the neck/shoulder
-Wearing a heavy backpack (traction injuries)
What is axillary lymphadenopathy?
-Enlargement of the axillary lymph nodes
What are some causes of axillary lymphadenopathy?
-Infection of the upper limb
-Infection of pectoral region and breast
-Metastases from breast cancer
-Leukaemia or lymphoma
-Metastases from malignant melanoma
Describe fractures of the scapula
-Uncommon
-Indication of severe chest trauma
-Seen in high speed road collision, crushing injuries, high impact sport injuries.
-Does not typically need fixation as tone of surrounding muscles holds fragment in place while healing occurs.
Describe fracture of the surgical neck of the humerus
-frequent site of fracture usually from blunt trauma to the shoulder/FOOSH
neurovascular structures at risk in surgical neck of humerus fractures?
-Key neurovascular structures at risk= axillary nerve + posterior circumflex artery.
Damage to axillary nerve in surgical neck of humerus fracture?
-Paralysis of deltoid + teres minor muscles.
-Patient will have difficulty performing abduction of affected limb.
-Loss of sensation in regimental badge area
Describe shoulder discloation
-Patient’s shoulder visibly deformed + visible swelling/bruising around the shoulder
-Movement of the shoulder will be severly restricted.
Describe anterior dislocations
-90-95% of dislocations are anterior.
-The arm is held in a position of external rotation and slight abduction.
Mechanism of injury in anterior shoulder dislocations?
-Direct blow to the posterior shoulder
-Joint is weak at its inferior aspect, head of humerus usually dislocates anterioinferiorly and displaces in an anterior direction due to pull of muscles.
OR
-Head of humerus may lie anterior-inferior to the glenoid
What is a bankart lesion + how does it occur?
-The force of the humerul head popping out of the socket often causes part of the glenoid labrum to be torn off.
-Small peice of bone may be torn off with labrum
What is a Hill-Sachs lesion + how does it occur?
-When humeral head is dislocated anteriorly, the tone of infraspinatus + teres minor means the posterior aspect of the humeral head becomes jammed against ant. lip of glenoid fossa.
-This causes a dent (indentation fracture) in the posterolateral humeral head= HSL
Describe posterior shoulder dislocations
-Far less common (2-4% of cases)
-Usually caused by violent muscle contractions due to:
>Epileptic seizure
>Electrocution
>Lightning strike
What are some other causes of posterior shoulder dislocations?
-Can also be caused by a blow to the ant. shoulder or when arm is flexed across body and pushed posterioly
How does patient present with posterior shoulder dislocation?
-Arm internally rotated and adducted
-Flattening/squarring of the shoulder + prominent coracoid process
-The arm cannot be externally rotated into anatatomcial posistion
Outline the problems in detecting a posterior shoulder dislocation on X-ray?
-Can easily be missed as it looks ‘in joint’
-As the arm is Internally rotated the projection of the humeral head changes to a more round shape
-‘the light bulb sign’
What is the MOI of inferior dislocations?
-rare (0.5%)
-forceful traction on the arm when the arm is fully extended over the head.
-may occur when grapsing an object above the head to break a fall.
Complications of shoulder dislocations (in any directions)
-Reccurent dislocations (due to damage of surrounding stablising tissues)
-Damage to axillary artery
-Damage to axillary nerve which arounds the NOH
-Significant fractures
-Rotator cuff muscle tears (SITS)
Describe calvicle fractures
-accout for 3-5% of all fractures
-Peak age in children + young adults
-80% of fractures occur in middle third of the clavicle (mid clavicular fractures
What is the MOI of clavicular fractures + treatment?
-Fall onto outstreched shoulder or hand
-Treated conservatively using a sling
-May require surgical fixation
What are the indications for surgical fixation in clavicular fractures?
-Complete displacement
-Severe displacemnet causing tenting of the skin, with risk of puncture
-Open fractures
-Neurovascular compromise
-Fractures with interposed muscle
-‘Floating shoulder’
What is ‘floating shoulder’?
-Clavilce fracture with ipsilateral fracture of the glenoid neck (break in clavicle and upper part of the scapula)
-The shoulder pulls out of place and looks like its floating (on imaging)
What will happen to the position of the arm + clavicular fragment in a displaced mid-clavicular fractures?
-Medial segment elevated by sternocleoidomastoid.
-Trapezius muscle is unable to hold lateral segment up so shoulder drops.
-Arm is pulled medially by pec major (adduction).
Describe rotator cuff tears
-Tear of one or more of the tendons of the four rotator cuff muscles (SITS)
-Frequently seen in primary care + orthopaedic outpatients.
-Management is conservative or operative
What are some causes of rotator cuff tears?
-extended use
-poor biomechanics
-muscle imbalance.
-Age-related degeneration.
-Repetitive overhead activity
What is the degenerative-microtrauma model in rotator cuff tears?
-With age blood supply to rotator cuff tendon decreases.
-age related tendon degeneration + chronic microtrauma= partial tendon tears
-these partial tears result in full rotator cuff tears.
Presentation of rotator cuff tears?
-Anterolateral shoulder pain radiating down the arm.
-Pain in shoulder when they lean on their elbow
-Pain in shoulder when reaching forwards
-Weakness of shoulder abduction
Describe calcific supraspinatus tendinopathy.
-Presence of macroscopic deposits of hydroxyapatite in tendon of supraspinatus.
-(Hydroxyapatite= crystalline form of calcium phosphate).
-Can be present in any tendon of the rotator cuff (most commonly seen in supraspinatus).
-multifactorial causes
Presentation of calcific supraspinatus tendinopathy?
-Acute/chronic pain
-Pain aggravated by abducting or flexing arm above the level of the shoulder.
-Lying on the shoulder
What are the mechanical symptoms of calcific supraspinatus tendinopathy?
-Stiffness
-Snapping sensation
-Catching
-Reduced range of movement
(all present due to presence of a large deposit)
What is the treatment of calcific supraspinatus tendinopathy
-Initially conservative: rest + analgesia
-Surgical treatment sometimes required for persistent symptoms.
Describe Adhesive capsulitis (frozen shoulder)
-Painful and disabling disorder in which the capsule of the glenohumeral joint becomes inflammed + stiff
-Restrics movement and causes chronic pain
What are risk factors for Adhesive capsulitis (frozen shoulder)?
-Female
-Epilepsy with tonic seizures
-Diabetes mellitus
-Shoulder trauma
-CT disease
-Thyroid disease
-CV disease
What are signs + symptoms of Adhesive capsulitis (frozen shoulder)?
-Severe pain causing sleep deprivation for prolonged periods
-Effect on daily life + work
-Some develop depression as a result
What is the treatment for Adhesive capsulitis (frozen shoulder)?
-Physiotherapy
-Analgesia
-Anti inflammatory medication
-Typically resolve with time
What is a surgical treatment option for Adhesive capsulitis (frozen shoulder)?
-Patients undergo manipulation under anaesthesia which breaks up the adhesions and scar tissue in the joint.
-Helps restore range of motion
-Intensive post-op physiotherpay helps maintain gained fucntion.
Describe OA of the shoulder
-Usually affect people >50yrs
-commonly affects the acromioclavicular joint
-treatment laddder is similar to OA in other joints:
>activity modifciation
>NSAIDs
>analgesia
What are some surgical treatment options for OA of the shoudler?
-Total shoulder replacement
-Arthroscopy (keyhole surgery) to remove loose peices of damaged cartilage.
What is Impingement syndrome (shoulder)?
-Supraspinatus tendon impinges on the coraco-acromial arch leading to irritation and inflammation.
-Treatment= treat the underlying cause
What causes impingement syndrome (shoulder)?
-Anything that reduces the space between the head of the humerus in the coraco-acromial arch.
-e.g. thickening of coracoacromial ligament, inflammation of supraspinatus tendon
When will pain be felt in impingement syndrome (shoulder)?
-When shoulder is abducted/flexed
-Shoulder overhead movement
-Lying on affected shoulder
-Painful arc between 60 and 120 degree abduction of the shoulder.
-grinding + popping sensation
