BPK 241 Lecture 9

Humerus

• Head

• Anatomical Neck

• Greater & Lesser Tubercles

• Surgical neck

• Shaft

Clavicle

• “Collar bone”

  • S shape

  • Subcutaneous

Scapula

• “Wing bone”

  • Inverted triangle shape

  • Spine, acromion, glenoid process & cavity fossa, coracoid process

Glenohumeral joint (GH)

• Type = Ball & Socket, synovial

• Articulation = humeral head & glenoid cavity (N.B., glenoid labrum)

Sternoclavicular joint (SC)

• Joint type = synovial

• Articulation = manubruim & clavicle

• Stability

  • Capsule

  • Anterior and posterior SC ligaments (downward pull)

  • Interclavicular ligaments (medial pull)

  • Costoclavicular ligaments (pull downward and medially)

• Movements

  • Mainly rotation, plus elevation and retraction, during shoulder and arm movements

Acromioclavicicular joint (AC)

• Joint type - synovial, gliding

• Stability

  • Superior & inferior AC ligaments

  • Coracoclavicular ligament

• Movements

  • Scapula (acromion process) & clavicle pivot upon each other (elevation, depression, retraction) in arm movements

Coracoclavicular joint (CC)

• Joint type = Syndesmosis

• Stability

  • Coracoclavicular ligament

• Assists in AC joint stability

Shoulder Movements

• Flexion & Extension, Abduction, Adduction, Internal Rotation and External Rotation

• Hence circumduction

Stabilizers

• Bony

• Capsular & coracohumeral ligaments

• Labrum

• Superficial muscles

• Tendon of long head of biceps humeri (in bicipital groove of humerus, to supraglenoid tubercle)

• Rotator Cuff Muscles

Passive Stabilizers

• Negative pressure

• Adhesion between two moist cartilage

• Adhesion Cohesion

Dynamic Stabilizers: Superficial muscles

• All arise from thorax or scapulae

• All insert on shaft of humerus

  • Deltoid (Abduction)

    • O = clavicle, acromion, spine of scapulae

    • I = deltoid tuberosity of humerus

  • Pectoralis major (Add, Flex, IR)

    • O = ribs, sternum, clavicle

    • I = anterior lip of bicipital groove

  • Latissimus dorsi (Add, Ext, IR)

    • O = thoracolumbar spine, ribs, ilium

    • I = anterior lip, bicipital groove

  • Teres major (Add, Ext, IR)

    • O = Lower 1/3 of lateral scapula

    • I = anterior lip, bicipital groove

Dynamic Stabilizers: Deep group muscles

• Aka “rotator cuff” muscles

  • All arise on scapula

  • All insert near humeral head

  • Supraspinatus (initial abd, stabilize head of humerus)

    • O = above spine of scapula

    • I = greater tubercle

  • Infraspinatus (ER)

    • O = below spine of scapula

    • I = greater tubercle

  • Teres minor (Add, ER)

    • O = upper lateral scapula

    • I = greater tubercle

  • Subscapularis (IR)

    • O = anterior (deep) surface of scapula

    • I = lesser tubercle

Force Couples

Forces working in opposite directions

Bursae

Especially subdeltoid & subacromial

Coracoacromial Arch

The superior lateral extension of the scapula and is comprised of the acromion, coracoacromial ligament, and coracoid

Shoulder Injuries

• Mechanisms

  • Throwing

  • Direct Blow

  • Resisting a force (especially in ABD/ER)

  • Fall on outstretched arm (FOOSH)

Shoulder Assessments

• HX & PHX

• Tenderness/ Pain level?

• Observation/ Deformity?

• ROM (active & passive)

• Strength tests

• Special tests

• Palpation

• Neurovascular status (brachial plexus, subclavian/axillary/ branchial artery)

• Beware of rapid onset of “frozen shoulder” if immobilized due to pain, splint of inactivity!

Brachial Plexus

Travels under clavicle from C5 to T1

Neurovascular Bundle

Small collections of blood vessels (veins and arteries) and nerves which supply the tissues of the chest wall.

Contusion

• Hx: direct blow

• SSx:

  • Pain, tendernes

  • Reduced ROM

  • Bruising, swelling

• DDx = fracture

• Tx:

  • POLICE

  • Early ROM; physiotherapy

  • No massage! No heat!!

Strain

• Hx = Resisting a force

• SSx:

  • Pain, worse with active movement

  • Reduced ROM

  • Point tenderness, bruising?

• Tx:

  • POLICE

  • Early ROM (passive, then active)

  • NSAIDs, tape

  • Physiotherapy & rehabilitation

• Notes:

  • 3rd degree strains may require surgery, and may not be obvious (. arthorogram, MRI, CT)

  • Tendonitis, tendinopathy is a common complication

Tendonitis (Tendinopathy)

• Hx = acute strain or overuse; impingement (e.g., swimming)

• SSx = as for acute strain (but prolonged duration)

  • Imaging X-Ray/ diagnostic ultrasound

• Tx:

  • Adequate rest, ROM

  • NSAID (and/or corticosteroid injection) - rare

  • Physiotherapy, retraining, rehab

  • Surgery?

Pitching Mechanics Arm Acceleration

• Pelvis rotation = 590º/s

• Upper trunk rotation = 1140º/s

• Knee extension = 380º/s

• Elbow extension = 2720º/s

• Shoulder rotation = 6950º/s

Subacromial Impingement Syndrome - SAIS

Pinching of the rotator cuff muscles

Risk factors for impingment

Overhead load and overhead work. Ex: Volleyball

Causes of Subacromial Impingement Syndrome

• Intrinsic

  • Primary Impingement

• Extrinsic

  • Dynamic Impingement

Primary Impingement

• Subacromial space (AHD) measurement < 7mm is risk factor for impingement

• Bone spurs

Primary Impingement Surgery

• Tendon repair

• Calcification

• Osteophytes/ bone spurs

• Subacromial decompression

Dynamic Instability - Pathobiomechanics

• Pain = Inhibition of lower rotator cuff muscles

• Dynamic instability = Decreased subacromial space (SAS) during shoulder elevation compared to asymptomatic side

• Result of upwards translation of humeral head during abduction

• If we reduce fatigue in the rotator cuff muscles experimentally - results in the humeral head migrating upwards at the initiation of abduction

• Tight pec major/ minor → anterior tilt of scapulae, limits scapular upward rotation, external rotation and posterior tilt = decreased SAS

• Posterior capsule tightness → GIRD = decreased SAS

• Small increase thoracic spine flexion = more elevation and anteriorly tilted scapulae at rest = decreased GH joint elevation

Bursitis

• Hx: Acute trauma or overuse

• SSx: Aching pain, tenderness, reduced ROM (abd) may lead to “frozen shoulder”

• Tx = as for tendinopathy

Sternoclavicular sprain (SC)

• Hx = direct blow, torsion, fall

• First degree

  • SSx = pain, tenderness, no deformity

  • Tx = rest, ice, NSAID, rehabilitation

• Second degree

  • SSx = as above (worse), plus some deformity, crepitus, bruising, reduced shoulder ROM

  • Tx = sling (4-6 weeks), ROM, NSAID, physiotherapy, rehab

• Third degree

  • SSx = as above (worse still), plus marked deformity

  • Tx = sling, stabilize, to hospital; follow up as above

• Precautions: 2nd and 3rd degrees send to hospital for imaging, if clavicle is displaced posteriorly it may put pressure on blood vessels, esophagus or trachea

Acromioclavicular Sprain (AC)

• Hx = direct blow, fall

• First degree

  • SSx = pain, worse on movement

    • Point tenderness, swelling, mild deformity

  • Tx = POLICE, sling, ROM, physio

• Second degree(rupture of AC ligament)

  • SSx = as above (worse) plus:

    • More deformity, crepitus?

    • Marked restriction in ROM

  • Tx = ice, sling, to hospital (X- Ray), then NSAID, physio, rehab

• Third degree (rupture of AC & CC)

  • SSx = marked deformity (step defect), pain, etc..(“separated shoulder”)

  • Tx = as for second degree, surgery?

Glenohumeral Sprain (GH)

• Hx:

  • Resisting a force (abd, ER)

  • Fall

  • Throwing

• SSx = same as for rotator cuff strain, but pain is marked both on active and passive movement

• Tx:

  • POLICE

  • Sling

  • Early ROM

  • NSAID

  • Physiotherapy

• Note: Third degree GH sprain is a “shoulder dislocation”

Glenohumeral dislocation

• Hx = as for GH sprain (+PHx?)

• Forward (anterior, subcoracoid)(much more common)

• SSx:

  • Humeral head palpable in axilla

  • Deltoid flat; indented; arm in abd

  • Severe pain and reduced ROM

• Tx:

  • Check neurovascular status!

  • NPO, sling, to hospital ASAP(X-Ray, reduction; if recurrent, surgery)

  • Agressive rehabilitation

• Downward (posterior, subglenoid)

  • SSx = same, except arm seems longer

  • Tx = same

• Note; recurrence is common (70-90% after first, vs 2% post-op)

Glenohumeral Dislocation: Management

1. Immediate immobilization, sling

2. Reduction by physician

3. X-Ray to make sure no fractures

4. General body conditioning (biking, speed-walking, running)

5. Range of Motion - attempt to regain full, non-restricted pain-free ROM, try to regain at all surrounding joints as well as they work together

6. Muscular strength - isometric for IR and ER, then rubber tubing exercises, then dumbbells and other resistant devices as pain allows

   • Isotonic, isokinetic, plyometric, scapular stabilization exercises

7. Neuromuscular control - relearning to use injured extremity in coordinated highly skilled movement

8. Functional progressions - increasing resistance and difficulty of exercises when it is pain free and completely functional

9. Return to Activity - based on functional performance

SLAP Tears

• Superior Labral tear from anterior to posterior

  • Many different classifications (7 to 10 depending on classification system)

  • Types 1 to 4 most common

SLAP Type 1

Partial tear of labrum where edges are roughed but not completely detached

SLAP Type 2

• Most common, labrum is torn off the bone due to injury (glenohumeral dislocation)

• Tx is reattachment of labrum, done arthroscopically using suture anchors

SLAP Type 3

• “Bucket handle” tear of labrum, torn piece hangs into GH joint and causes locking, popping, clunking

• Tx involves removal of bucket handle segment, repair any remaining unstable labrum with anchors

SLAP Type 4

• Tear of labrum extends into the long head of biceps tendon

• Tx involves reattachment of the labrum & repair of biceps tendon (biceps tenodesis)

• Tear like cheese string

Glenohumeral Fractures

• Hx = dislocation

• SSx = as for dislocation

• Types = head of humerus (Hill-Sachs) - hatchet defect

• Glenoid process (Bankhart lesion)

• Tx = hospital to assess; X-Ray, surgery?

• Complications = neurovascular; arthritic

Clavicular Fractures

• Hx = direct blow, fall (mid 1/3)

• SSx = deformity, crepitus, pain, tenderness, swelling, marked reduction in ROM; positive X-ray

• Tx = check neurovascular status, hospital to assess, sling (6 to 8 weeks), physiotherapy

• Surgery rare