Shoulder

Glenohumeral Joint Stability

• The scapular plane sits 30 degrees anterior to the coronal plane.
• Abduction requires external rotation to prevent the greater tuberosity from impinging on the acromion.
  • An IR contracture results in a decreased abduction ROM of 0-120 degrees.
• Full abduction involves both GHJ and scapulothoracic movement.
  • 120 degrees is achieved by GHJ movement, and 60 degrees is achieved by movement of the scapulothoracic joint .

Static Restraints of the Glenohumeral Joint

• The glenoid and humeral head have limited articular surface, making joint congruency a minor stabilizing factor.
• The labrum increases the socket depth by 50%, enhancing stability without limiting range of motion.
• Anterosuperior labral variants can occur at the 1-3 o'clock position and include sublabral recesses, sublabral foramen, and Buford complexes (absent labrum + cord-like MGHL).
• The anterior-superior labrum has the poorest blood supply.
• Negative intra-articular pressure in the capsule contributes to posterior stability.
• The coracohumeral ligament, which is in an adducted position, resists inferior translation and external rotation.
• The FADIR tests posterior translation
• All Glenohumeral Ligaments attach from labrum

Dynamic and Regional Considerations

• Glenohumeral ligaments attaching from the labrum provide stability in different arm positions.
• At 90 degrees of abduction, the anterior band of the IGHL resists anterior dislocation (Bankart Lesion), while the posterior band resists posterior translation (Kim Lesion).
• The band is a primary structure that gives way in throwers during a classic anterior dislocation . It's labral attachment causes Bankhart lesions
• The posterior band resists posterior displacement at 90 degrees abduction/flexion and IR, contributing to SLAP tears if tight.
• The rotator cuff's main role is to compress the humeral head against the glenoid.
• All cuff muscles counter deltoid to limit superior migration during abduction
• During ER, the infra, teres minor and supra are all active.
  • Subscapularis flexibility and tightness provide mechanical restraint against anterior translation.

Serratus, LHBT, and Throwing Phases

• The serratus and trapezius muscles facilitate scapular rotation and tilt above 90 degrees elevation.
• Scapular rotation & tilt maintains glenoid/humeral congruency under dynamic forces.
• The LHBT anchors to superior labrum and reinforces labrum and capsule with activation.
  • It can also be a source of weakness/shearing in SLAP lesions.
• Throwing is divided into 4-5 phases ( follow through and deceleration are commonly grouped together)
  • Wind up is minimal force. Driven trunk and hip rotation.
  • Cocking early abduction. Loaded ER, injury-GIRD, Int impingement
  • Acceleration forceful IR leads to Stabilizing cuff injuries valgus elbow demand (UCL)
  • Deceleration eccentric force 500N on posterior cuff limit/extend
  • Follow Through

Glenohumeral Dislocations: Epidemiology

• Anterior dislocations comprise 95% of glenohumeral dislocations.
• Occurs annual 1.7% general, Male and young likely to recurrent as activity
• recurrence likely if recurrent younger years. 90 under 20 YO and 50% <25

Glenohumeral Dislocations: Factors and Actions

• Dislocations is previous, loose, cuff tear. esp Ax nerv
• Anterior with abduction, external rotation, and anterior-to-posterior force on the elbow. A posterior-directed force to the shoulder is a less common cause.
• Electrocution and Seizures = Post Dislocation
• Axial force can adduction of Internally rotated arm causes Disruption
• Chronic dislocation +Repetitive Microtrauma – aggravating
• inferior w/axial with Abd
• Anterior band IGHL goes under Load of violent ER

Glenohumeral Dislocations- Damage

• Anterior band of IGHL gives at labral attach or avulsion by bone.
• Cuff Resist Anter dislocation with Postior activation minor. Passive of Subscap forward restraint
• Cartlidge Damage = labral Damage BHAGS bankart 1ghl
• Common HAGL avulsion in old and indication of surgery better results
• Glenio labral Articulation Deform damage , heals med or post.

Glenohumeral Dislocations- nerve and cuff

• L tuberosity=Rare In old or young people
• Aux nerve is only 5.
• cuff=30>40tear to much higher 80>60YO group more

Glenohumeral Dislocations- Bone and history

• Bony banks is to 49%
• Recent bony defects 20-25% and need bony, some 15 athetleet
• hills sachs most
• tubertoty fracture to high with anterior Dislocation >50
• hx. and MOI=abd or external irectorce

Glenohumeral Dislocation- Test and Exam

• test and abd by force
• poppoing. paras, badde,,laxity,shoulder chronic
• General, difficult
• inspect adb and rotation of bone loss
• restrciton on range or resistance is post of humeral head void

Glenohumeral Dislocation- Tests

• chronic lax
• beighoton hyper extention etc on side
• gauge
• load 2 or morse planes
• ant apprehension test supin instability . relocation posterior. aux nerve
• Post in add and internal inability torotation
• prominent shoudel
• axil apply and mvo eto flextions

Glenohumeral Dislocation- XRAY finding

• kim test applies all
• sup and adb
• XRay and test, dislocation and impungnent
• GH, Hill ligh tpost view

Glenohumeral Dislocation- Management

• Enlocstion On all y ax views
• bankart post, all, hills stycker v, GT fractureser, view lt
• Bone with positive therapy etc

Glenohumeral Multidirectional Instability (MDI)- criteria

- instability in two or more planes while symptomatic.

Glenohumeral Multidirectional Instability (MDI)- details

- peaks in second and third decades of life. Involves laxity with shoulder overuse

Glenohumeral Multidirectional Instability (MDI)- Predisposong facotrs

- includes females with power, rotator cuff, and general Eherls . Rarely.
 micro trauma , ligaments, stretch are key.

Glenohumeral Multidirectional Instability (MDI)- exam

    o   what test is a two position in two directions

Beight on and ER are high to see and exam. Palp

Acquired Instability Due to Overstress (AIOS)

• A condition primarily affecting throwers and overhead athletes.
• Repetitive overhead motions cause anterior capsule laxity and posterior capsule issues.
• This can have SubAcromial impingement
• decreased ROM, less with GIRD, post tightness for caps and bad test is all

Glenoid

-   Lax, ligated, capsulated, test

High failure at all so cuff better

Glenoid Laxity

• Instability of a joint, in general, relies on if there is issues, needs or it lacks it
• Can be one or both sided
• Instability means a dislocation or at least dislocation
• lax joints also

Rotator Cuff Tendinopathy

• Rotator cuff impingement often equals tear with rotator cuff. Often all disorders or older patients
• 45-65% disorders and linked with poor bio mechanics and hook. More at top

Rotator Cuff Tendinopathy and loading

• Most on tenon load and height load or instability or tension. Also with some damage from a tear

Rotator Cuff Tendinopathy pathology

• Unstable so bal onee
• Combination and extrinsic, with joint and some tension
• Extrinsic more, with shoulder or other, or biceps insertion all messed up

###Rotator Cuff Tendinopathy- features and tests

• Features have test + signs like a tear
• acromian

Rotator Cuff Tear : Exam Findings

• Anterior sub, posterior internal and release with repeating.
• Tests internal and high

Rotator Cuff Tear: History and Interventions

• History is high and surgery or low with exercise, injections, exercises, more and or for a long treatment

Rotator Cuff tear-indications

• Age matters and more of full if has or less of tear etc
• Releasing tear and other for what to do

Rotator Cuff tear - Subclavius

• All are good with repair or cuff, low or great, only with what to get , may need time

calcified Tendopath

• age gender. supra or inf is more
• Endocrine more. in zone then issue. calcium issue then more
• Form resorp and remodel and take new

calcified Tendopath test

• Sub or imping all
• Calcium one 15 insertion

Capsular issues

capsular issues, throwers, late or early rotation

SLAP tears

Occur high due biceps load and scapular motion. All throwers

SLAP tears - factors

Load and high . Test + pain or

SLAP and biceps exam

• Bicep Groove tenderness and may be post side loading

###SLAP - Surgery & Rehab

• Long high strength loss. So balance exercises wlll better help

biceps Tenso exam + findings

• Anteroir of bi esp Groovwe . some snapping or upcut

###ACJ - shoulder or AC

• 9 shoulder injuries are likely AC
• more in Males. Direct to shoulder often by a fall

ACJ- types of injuries and what to look for all

• ACj or lavicie damage is likely with or without
• Cross arm is likely, contour damage

ACJ dislocation types

• CC likely with AP. also weighted stress. look shock relocation
• I IIII A/b need lateral all

ACJ dislocations 5 and after

• V is also
• CC restoration needs high repair but less will help shoulder
• Non oop
• types . some atv and no stability

###ACJ -clavicle and pain and how

• Type 10

Distal clavicle Osteolyis age

• Young, Weightlifers , Rare as such

Distal clavicle Osteolyis history

• Pain load joint is similar
• Find Osteopero .

Clavicle fracture, where is it and what do

• The med shaft and 1 or 3 is most. with muscle around to fracture, may cause

shafts what and how

• sling and fig . A/PROM later.. what ###Shaft fx2 to 10/6 , NonUnions and older and fem . sm

distal facts and history

• distal. older,.
• Neer + bone tests
• Acl ligaments to look most etc

Neurovascular

• Nerve can be injured so
• Post notch
• compression more
• Traction often shoulder

SupraScapular

• All by traction
• Compression
• EMG with
• Decompress or ganglion it

Thoracic outlet.

• Between is most, or the space
• Scalene, shoulder, 20 to 6
• Muscle of the arm for Winging etc