Shoulder/Elbow Flashcards
5 phases of throwing?
Phases of throwing:
1-Wind up
2-Cocking: early (deltoid); late(high torque phase w/ max shoulder ext and elbow valgus w/ peak supra, infra and teres minor activation)
Phase where MUCL shows instability/elbow valgus stress highest (late cocking)***
3-Acceleration: early (triceps); late (pec major, lat, serratus)
4-Deceleration: eccentric of all muscles…HIGHEST torque phase/MOST HARMFUL part of throwing (SLAP, biceps injuries)
5-Follow through: Where body rebalances and stops forward motion
What muscles help provide medial elbow support to prevent valgus instability during pitching?
FDS
FCU
What ligament prevents inferior restraint with arm at 0 degrees or adducted?
SGHL and CHL
What ligament prevents anterior and posterior restraint with arm at 45 degrees or abducted?
MGHL
What ligament prevents posterior restraint with arm at 90 degrees or 90 deg forward flexed, abducted, and IR?
Posterior band of IGHL
tightness leads to internal impingement nd increased shear across superior labrum (SLAP)
What ligament prevents anterior and inferior restraint with arm at 90 degrees and maximally ER/late cocking of throwing?
Anterior band of IGHL
What is a Buford complex?
Absent anterosuperior labrum and cordlike MGHL
1.5% population
Attaching complex will lead to painful and restricted ER (with arm at side**) and elevation **
What is included in rotator interval?
CHL, SGHL, capsule, Long head of biceps
What is major blood supply of humeral head?
Posterior humeral circumflex artery
Benefit of arthroscopic repair for anterior instability vs open?
Preservation of ER***
Spares subscap and much ofanfterior capsule
Hamada classification for rotator cuff arthropathy?
Gr 1: acromiohumeral interval > 6 mm
Gr 2: Interval <5 mm
Gr 3: <5 mm with acetabularization of acromion
Gr 4: GH arthritis
Gr 5: humeral head collapse
Lat transfer performed for?
Who is it good for?
Risks?
Pseudoparesis with ER***
Good for: young laborer
Risk: radial nerve***
Runs along anterior surface of lat, 3 cm medial to humeral head insertion
Posterior branch of axillary nerve
Runs in deep fascia of posterior deltoid
Pec transfer for?
IR deficiency and subscap insufficiency
Upper portion or whole pec transferred near subscap insertion on lesser
Going UNDER conjoined tendon more closely replicates vector forces of subscap**
Risk: Musculocutaneous nerve injury***
Rotator cuff footprint
How wide is Supra insertion?
How far from articular cartilage?
How long AP (supra and infra)?
Medial-lateral width = 14-16 mm (6-8 mm tear = 50% partial thickness tear)
1.6-1.9 mm from cartilage
20 mm in AP diameter
What % of 60 y/o patients will have a rotator cuff tear on MRI?
approx 55%
Treat bursal sided or articular sided rotator cuff tears more aggressively?
Bursal sided (repair these when >3 mm/25% in depth)
Articular sided tears complied and fixed when 50% or 6 mm
Double row cuff repair vs single row?
Dbl row show LOWER retear rate***
Higher ultimate tensile load to failure***
No diff in pain score, functional score, time to healing
Where will RCR fail?
Risk factors for failure
failure to heal, causing pull out from repaired tissue***
Risk factors >65*** (Highest risk factor***) Large tear Muscle atrophy*** DM Smoker Tear medial to glenoid Concomitant AC and/or biceps procedure at time of RCR***
Does PT or guided early RoM improve stiffness at 1 year after RCR?
No
Who does poorly after a lat transfer?
Subscap tear patients*
Women do worse than men*
Ptswith less than 90 deg FF
How long to protect RCR after surgery?
Repaired tendons should be protected from stress for minimum 6 weeks and more likely 8 weeks***
Compared to non workers comp patients that underwent RCR, workers comp patients do better, worse, same functionally and with satisfaction of procedure?
Worse functionally
Lower patient satisfaction
When treating subscap tear, what to do with biceps?
Tenotomy or tenodesis***- better clinical outcomes
What factor has been shown to be increased in patients with subacromial bursitis?
Metalloproteases*** and other inflammatory markers (COX, TNF-alpha, IL1, IL6)
What type of crystals in calcific tendonitis?
Calcium carbonate crystals***
post op rehab after biceps tenodesis?
Avoid active forearm supination with elbow at 90 deg
when to operate on AC joint?
- lateral clavicle displaced through trapezius
- coracoclavicular distance greater than 100% of contralateral side
- normal is 11-13 mm - inferior dislocation of lateral clavicle
Outcomes of type 3 AC separations treated with and without surgery?
Non operative have higher
DASH scores at 6 weeks in 3 months
equal function at 1 year
lower rate of secondary surgery for removal of hardware compared to those treated operatively
nonsurgical LESS LIKELY to develop acromioclavicular arthritis*** ( lack of articular surface contact)
what type of failure will be symptomatic in an acromioclavicular fixation case treated with a modified Weaver Dunn?
Reconstruction does not restore the native stability of the AC joint.
Persistent horizontal/ anterior to posterior instability may cause persistent symptoms***
what views most accurate for the AC joint radiographically?
Zanca view
what causes distal clavicle osteolysis?
Repetitive stress and microfracture in the distal clavicle which leads to osteopenia
mostly males in their 20s. Commonly seen in weightlifters.
How test for laxity of the rotator interval?
Pt shows:
Increased external rotation with the arm fully adducted and at 90° abduction***
tightening rotator interval will most significantly decreased range of motion in external rotation with the arm ADDUCTED**
what defined generalized ligamentous laxity?
Beighton’s criteria greater than 4/9
able touch palm still floor while bending at waist - 1 point
Genu recurvatum - 2 point
elbow hyperextension -2 points
MCP hyperextension - 2 point
Thumb abduction to the ipsilateral forearm - 2 points
MRI finding of multi directional instability?
Capacious capsule without presence of tears
Side effects of radiofrequency or laser thermal capsularrhaphy?
glenohumeral chondrolysis***
Recurrent instability***
what size defect defines critical bone loss in the bony Bankart lesion?
20-25%
newer studies say may be as low as 13.5%
what % of traumatic dislocations and traumatic subluxations cause a Hill-Sachs defect?
Dislocations: 80%
Traumatic subluxations: 25%
what x-ray view to see glenoid bone loss? Hill-Sachs lesion?
Glenoid bone loss: West Point view
Hill-Sachs lesion: Stryker view
what are risks of Re dislocation after a shoulder dislocation?
Age less than 20 years old -highest risk Male Contact sports Hyperlaxity Glenoid bone loss greater than 20 25%
does mobilization provide benefit in decreasing recurrence rate after shoulder dislocation in patients with Bankart lesion?
Studies have not shown any benefit of mobilization greater than 1 week for decreasing recurrence rates.***
How many anchor should be using arthroscopic Bankart repair?
at least 3, less than 3 anchors is a risk factor for failure***
nerve injury after Laterjet procedure how to treat?
What nerve is most common?
treat with observation for 3 is 6 weeks, delayed EMG if deficits persist***
Musculocutaneous nerve is the most common***
occurs during instrumentation around the conjoined tendon
what motion should be avoided after a remplissage procedure?
Forward flexion and adduction***
this motion void tension the posterior capsule and jeopardize the repair
how does the Laterjet procedure provide stability?
Increases the glenoid bony support in excursion distance prior dislocation***
The conjoined tendon passing through the subscapularis becomes a supportive sling***
The remnant of the CA ligament can be used to aid in repair of the capsular tissues***
what glenohumeral ligament is the primary restraint to internal rotation?
Posterior band of the IGHL***
when to do a McLaughlin procedure/ open reduction with subscapularis transfer?
Chronic dislocations less than 6-month-old
Reverse Hill-Sachs defect less than 40%**
if greater than 6 months or reverse Hill-Sachs defect greater than 40%, hemiarthroplasty***
most common complication after labral repair?
Stiffness
What position will the arm be locked in a posterior shoulder dislocation?
internal rotation***
What is internal impingement of shoulder?
Who does it affect?
What phase of throwing?
What changes does it cause?
What is etiology of internal impingement?
Cause of pain in overhead athletes caused by repetitive impingement of the undersurface of cuff
Throwing/overhead athletes
Impingement occurs during max arm abduction and ER –> Late cocking and early acceleration***
Fray of posterior rotator cuff w/ posterior and superior labral lesions
Hypertrophy and scarring of posterior capsule glenoid (Bennett lesion)***
Cartilage damage at posterior glenoid
Etiology = Tightness of POSTERIOR BAND IGHL**
What is a Bennett lesion in shoulder?
Scarring and exostosis of posterior glenoid secondary to internal impingement with throwing ***
What does sleeper stretch do?
Stretches Posterior band of IGHL***
What is Little Leaguer’s shoulder?
What type of injury (SH type)?
Tx?
Overuse injury resulting in epiphysiolysis of proximal humerus
Salter Harris type I injury***
WIDENING proximal humerus physis***
Tx: cessation of throwing for 3 MONTHS*** followed by PT and progressive throwing program after sufficient rest
Glenohumeral internal rotation deficit (GIRD)… definition?
when will kinematics be deranged?
Def: Decrease in IR of 25 deg or more when compared to contralateral side ***
Kinematics: When ER gain is LESS than IR lost***
If GIRD (loss of IR) is less than ER gained, then shoulder maintains normal kinematics***
What conditions are ass’d with GIRD and internal impingement?
SLAP tear*
PASTA tear*
Posterior band of IGHL tightness
What happens to humerus during cocking phase of throwing in patients with GIRD?
Humerus is translated posterosuperiorly***
Rehab after SLAP tear surgery?
Week 1-4: passive and active assist flexion in scapular plane***
Avoid abduction and ER and resisted biceps exercises
Week4-6: progress to active ROM, isometrics
Week 6-12: Fxnl exercise and light strengthening
Weeks 12+: Advance strength and ROM, sport specific exercises
Return to sport at approx 6 months***
Risk of failure with SLAP repair?
Ass’d with age >36 y/o***
Biceps tenodesis better for this group***
Scapular winging: medial vs lateral
Etiology?
Medial: dysfunction of serrates anterior (long thoracic nerve, C5-7)
Lateral: dysfunction of trap (CN XI/spinal accessory)
Medial scapular winging…PE?
Tx?
PE: Inferior medial scapula elevates and protrudes posteriorly and medially (worsened by forward arm flexion)***
Manual stabilization of scapula improves pain and increases flexion and abduction ***
Tx: PT and obs: min 6 months (more likely 18-24 months), strengthen serratus
Muscle transfer: split pec major transfer (sternal head of pec)***
ST fusion***
Lateral scapular winging…causes?
Tx?
Causes: most common iatrogenic (posterior triangle of neck, cervical lymph node Bx or radical neck dissection)***
Tx: Observation and activity modification
Neurolysis of CN XI
Eden lange transfer: levator scapulae and rhomboid to medial border of scapula to lateral border***
ST fusion***
What is the quadrilateral space?
What is in space?
Sx?
PE?
LATERAL to Triangular space Superior and medial to triangular interval***
Interval contains radial nerve and profunda brachii*** (split of triceps and below teres major)
Superior: subscap and teres minor
Inferior: Teres major
Medial: long head of triceps
Lateral: surgical neck of humerus
Contents: Axillary nerve*
Posterior circumflex artery*
Sx: Poorly localized pain of the posterior/lateral shoulder
Worse with overhead activity or late cocking/acceleration phase of throwing***
PE: Atrophy of teres minor and deltoid***
Suprascapular notch nerve entrapment vs spinoglenoid entrapment?
Suprascapular notch: Weakness in both supra and infra***-
Spinoglenoid: Infra only***
Where does supra scapular nerve originate from?
Superior trunk of plexus***
C5-6***
What is the triangular interval? What does this include?
Triangular interval contains radial nerve and profunda brachii artery
Other names for Parsonage-Turner syndrome?
Factors ass’d w/ poor prognosis?
Brachial neuritis
Neuralgic amyotrophy*
Idiopathic neuralgic amyotrophy*
Poor prognosis: Female***, lower trunk involvement, persistent pain and no motor fxn at 3 months
Hereditary cases
Age has NO EFFECT on prog
Timing of recovery: 2/3 have recovery of motor function w/in 1 month
May take up to 8 years to gain full strength
Pec rupture - which head most common?
Sternocostal head most common
Fails in excessive tension on a maximally eccentrically contracted muscle
Inferior fibers of sternal head fail first, then superior, then clavicular head
Innervation of pec major?
Lateral (C5-7) and medial (C8-T1) pectoral nerves***
Medial supplies lower muscle belly*
Lateral supplies upper portion*
Shoulder AVN classification and tx? (Cruess classification)
Stage I: normal XR w/ changes on MRI, core decompression
Stage II: Sclerosis, osteopenia, core decompression
Stage III: Crescent sign indicating subchondral fx, Resurfacing or hemi
Stage IV: Flattening and collapse, resurfacing or hemi
Stage V: Degenerative changes to glenoid, TSA
What elbow ligament should be released to gain additional elbow flexion?
Posterior band of MUCL***
What percent of patients getting TSA have cuff tear?
Approx 10%* (vs 60 y/o w/o arthritis nearly 60%)*
Isolated supra tear w/o retraction can proceed with TSA***
What condition makes TSA have worse results?
What is most common cause of poor outcome in TSA?
Post capsulorrhaphy arthopathy***
Most common: Rotator cuff tear***
Others: fx, glenoid loosening, etc
What is ass’d w/ scapular notching for reverse TSA?
Preoperative superior glenoid erosion ***
Decreased ROM, strength, constant scores
Position of shoulder for shoulder fusion?
30-30-30 position***
30 degrees of abduction, FF, IR***
Components of MUCL
Components:
1- Anterior oblique ligament*
Strongest ant most significant stabilizer to valgus stress*
Subdivides into anterior and posterior bands
Anterior: primary restraint to valgus, nearly isometric***
Posterior Increasing strain during higher degrees of elbow flexion
2: Posterior oblique ligament/posterior bundle*
Demonstrates the greatest change in tension from flexion to extension* (tighter in flexion)
3: Transverse ligament: no contribution to stability
MUCL anterior bundle…what arc of motion does it contribute stability?
Where does it insert?
30-120 degrees of flexion***
Sublime tubercle***
PE/Sx with pitcher’s elbow/valgus extension overload?
XR?
Risk of surgical tx?
Pain in posteromedial elbow with full extension
Pain in deceleration phase***
Loss of terminal elbow extension***
XR: osteophyte formation int he posteromeidal olecranon fossa***
Surgical tx risk: can resect too much olecranon and increase MCL strain in future***
Risk factors for Little League elbow?
Greater than 80 pitches/game
More than 8 months competitive pitching/year
Fastball >85 mph
Continued pitching with fatigued arm/arm pain
Participating in showcases
What si primary stabilizer to varus and ER at elbow?
Where does it originate and insert?
LUCL***
Originates from lateral humeral epicondyle***
Inserts onto the tubercle of the supinator crest of ulna***
What does lateral pivot shift test at elbow? How is it done?
Tests for PLRI/LUCL injury
Test by placing pt supine with arm overhead, forearm supinated and VALGUS stress applied while brining arm from full extension to 40 deg flexion***
With flexion, triceps tension reduces radial head
Where do partial biceps avulsions occur at insertion?
Primarily occur on the RADIAL side of tuberosity footprint***
Risk factors for distal biceps avulsion?
Anabolic steroids
Smoking*** (7.5x than nonsmokers)
Hypovascularity
Intrinsic degeneration
What are two insertions of distal biceps?
Short head attaches DISTALLY on radial tuberosity*
Short head = better flexor*
Long head attaches PROXIMALLY*** Better supinator (furthers from axis of rotation)
1 incision vs 2 incision for distal biceps
Both: highest risk is for LABCN injury (more common in 1 incision)***
LABCN injury causes numbness on lateral side of volar arm***
1 Incision: More likely to have PIN injury***
2 incision: higher risk of HO and synostosis***
Where does ECRB originate and insert?
Vs ERCL?
Originate: Lateral epicondyle
Inserts: third metacarpal**
ERCL: Lateral supracondylar ridge to second metacarpal***
Does PT work better, worse or same vs steroid for tennis elbow?
PT works BETTER***
Steroids resulted in worse outcomes vs placebo***
What is antagonist of ECRB?
FCU (NOT FCR)***
Contraindications to Total elbow?
Active infxn
Charcot joint
Active patient <65
Olecranon osteotomy*** (to maintain competency of elbow extensor mech)
Postop for TEA - motion?
Early period of immobilization***
Early motion after TEA ass’d w/ wound complications, instability, hardware loosening***
Keep still for 4 wks**
Which patient and type of implant has best TEA survivorship?
RA patient with semi-constrained implant***
Semi constrained has best survivorship over unconstrained or constrained
When to do bankers repair vs Laterjet if given size of radius of glenoid and size of fractured piece in superior to inferior?
[(B - A) / 2B] x 100 = percent of bone loss
B = non fractured radius, A = fractured side radius***
Laterjet if >20 - 30%***
If fractured piece length sup/inf is larger than B, then dislocation resistance is <70% normal shoulder
What elbow angle lowers pressure on cubital tunnel/ulnar nerve?
40-50 deg***
How much retroversion is correctable by preferential anterior reaming for TSA?
15 degrees***
Reaming with more retroversion = excessive bone removal from glenoid vault –> insufficient bone stock for secure glenoid component fixation***
Which way to put elbow after LCL repair?
PRONATED**
keep supinated with MCL***
What happens to radial head during lateral pivot shift at elbow with posterolateral instability?
Radial head dislocates POSTERIORLY DURING EXTENSON and reduces with flexion***
With the forearm in maximal supination and valgus stress applied to the elbow, the radial head is forced posterior to the capitellum as the elbow is brought into progressive extension, revealing a dimple on the lateral aspect of the elbow. This typically occurs at roughly 30⁰ of flexion. As the elbow is flexed, the radial head reduces.