Shoulder/Elbow Flashcards
What is an anterosuperior RC tear?
Tear extending from subscap to or through the supraspinatus tendon
How to release adherent subscap tendon for repair.
Anterior surface
Release from behind the tip of coracoid and coracoid neck. Release behind the conjoint tendon.
Superior margin
Released from coracoid (release CH ligament too, basically skeletonizing coracoid)
Inferior margin
Axillary nerve and artery coursing from A to P around 3-5mm medial to musculotendinous jxn.
Posterior surface
Released from anterior capsule and glenoid neck
Loss of labrum decreases translational resistance by what percentage?
20%
What prevents posterior displacement with shoulder in flexion, IR and ADDuction?
SGHL and CHL
Posterior band of IGHL limits posterior displacement in what arm position?
Shoulder abduction
SGHL/CHL function?
Resist inferior translation and ER with arm adducted at the side, in neutral rotation.
Also limits posterior translation with arm flexed, IR and adducted
MGHL function?
Limits anterior translation with arm abducted to 45 degrees
Contents of rotator interval?
CH, SGHL, long head biceps
Primary restraint to anterior translation with abducted arm
Anterior band of IGHL
Most common associated fracture with a posterior shoulder dislocation?
Humeral neck (55%)
Then LT (42%)
then GT (23%)
Prevalence of reverse hill sachs and reverse bony bankart in posterior shoulder dislocation?
29% reverse hill sachs
5% reverse bony bankart
Algorithm for addressing reverse Hill sachs lesions
<20%
- Scope or open reverse Bankart repair
- McLaughlin Procedure
(peel and transfer SS into defect, or just anchor and suture SS into defect in situ)
**Must leave inferior rim of SS anatomic to preserve circumflex vessels!**
20-40%
Modified McLaughlin (LT osteotomy and transfer into defect)
Elevation of impaction, bonegraft
>40%
Arthroplasty or Allograft
Axillary nerve - how far from glenoid?
Which shoulder position maximizes the distance?
Mean of 12.4 mm from 6 o’clock glenoid
Abduction, ER and traction.
Nerve supply to subscap
Upper and lower subscapular nerve
Nerve supply to teres major
Lower subscapular nerve
Nerve supply to latissimus dorsi
Thoracodorsal nerve
Nerve to pec minor
Medial pectoral nerve
(vs pec major which is medial and lateral)
Location of thoracic outlet and other locations of compression
Between anterior and middle scalenes
Sites of compression
Abnormal scalene anatomy
Large transverse process
Cervical rib
Scapular ptosis
Clavicle or 1st rib malunion
Complications of TSA in order:
component loosening
instability
periprosthetic fracture
rotator cuff tears
neural injury
infection
deltoid muscle dysfunction
Elbow arthroscopy portals (7)
List nerves at risk for each
- Anterolateral (just anterior to RC joint) RADIAL and LABCN
- Anteromedial (1-2cm anterior and distal to medial epicondyle) MABC and MEDIAN
- Proximal anteromedial/anterolateral portals (each 2cm prox to epicondyle and just anterior to supracondylar ridge) AM: MEDIAN&ULNAR AL: RADIAL
- Direct lateral (soft spot)
- Distal ulnar (3-4cm distal to RC joint along lateral border of ulna)
- Direct posterior (3-4cm prox to tip of olecranon) PABCN&ULNAR
- Posterolateral (level of tip of olecranon, lateral side) PABCN
Insertion of biceps on bicipital tuberosity?
Long head proximal and short head distal.
Both ulnar.
Distal biceps tendon repair:
1 vs 2 incision technique
Equal function at 2 years
2 incision technique - 10% more flexion strength
LABCN injury: 40% in 1 incision, 7% in 2 incision group
Equal HO rate
Counsel re: nonop distal biceps treatment
Will lose 50% supination strength
Will lose 30% flexion strength
Will lose 15% grip strength
More common: proximal or distal biceps tendon rupture?
Proximal!
Four special test for medial elbow
Valgus stress test at 30degrees
Milking maneuver
Moving valgus stress test (pain b/w 120 and 70)
Valgus extension overload test (snap elbow into extension with valgus stress on it)
Most throwing MCL injuries in baseball occur during which phases of throwing?
Late cocking/early acceleration
Difference in mode of failure of LUCL vs MCL in terrible triad injuries
LUCL almost always avulsed off lateral epicondyle
MCL can be avulsed off either origin or insertion, or midsubstance tear.
Test for elbow stability after terrible triad fixation?
Hanging Arm Test
Elbow in extension and full supination against gravity. Fluoro AP and lateral must show congruent joint. If not, fix MCL and/or exfix
How much of the anteromedial coronoid facet is supported by ulnar metaphysis?
40% supported
60% unsupported
O’Driscoll classification of coronoid fractures
- Tip
- i. Anteromedial rim
2ii. Rim and tip
2iii. Rim and sublime tubercle - Base
Postop immobilization position after repair of valgus posterolateral instability and varus posteromedial instability
Valgus posterolateral: in pronation (neutral if MCL repair done)
Varus posteromedial: in neutral
Best xray to assess acromion profile
Supraspinatus outlet view
Phases of calcific tendonitis?
Type 1 (painful) fluffy appearance, “resorptive” phase
Type 2 (non painful) well defined calcification. “Formative” phase
Goutallier classification
0 normal
1 fatty streaking
2 more muscle than fat
3 muscle = fat
4 more fat than muscle
What is the “comma sign” and what does it signify?
Arc formed by SGHL/CHL complex.
Tip of comma at the superolateral aspect of the avulsed subscapularis tendon
Surgical indications for partial thickness RC tears
Failure of nonop mgmt
Bursal sided tear >25% (or 3mm thickness)
Articular sided tear >50% (or 6mm thickness)
What is a Bennett lesion?
Exostosis of posterior glenoid rim.
Associated with internal impingment:
Posterior capsular tightness leading to posterosuperior shift of humeral head. During ER and abduction (throwing) can have peelback of superior labrum, articular sided posterior cuff fraying, cartilage damage of posterior glenoid, and Bennett lesion.
Seebauer classification of RC arthropathy
1: No proximal migration (centred)
A:Stable
B:Medialized
2: Proximal migration
A:Limited stability
B: Anterosuperior escape
Three factors to help guide surgical tx of RC arthropathy.
Age?
Young: Hemi
Old: RTSA
Can they elevate?
Yes: Hemi
No (pseudoparalysis): RTSA
Anterosuperior escape?
Yes: RTSA
No: Hemi
What is a West Point axillary view?
What does it show?
Prone, shoulder abducted to 90 with elbow flexed.
Beam 25 off midline and 25 above horizon
Shows glenoid bone loss
What is a Stryker Notch view?
What does it show?
Supine with hand on head. Beam angled 10 cephalad
Shows Hill Sachs lesions
In MDI surgery after capsular shift, what is risk of closing the rotator interval?
Risk losing ER range of motion
Classify SLAP lesions!
1: Labral fraying, biceps anchor intact (debride)
2: Labral detachment, biceps detached (reattach)
3: Bucket with intact biceps (debride bucket)
4: Bucket with detached biceps (debride bucket, tenodese/tenotomy)
5: SLAP with anterior labrum (repair)
6: Superior flap tear aka parrot beak (repair or debride)
7: SLAP w/ capsular injury (repair)
Describe a Buford complex.
Labral anatomic variant with absent anterosuperior labrum, instead there originates a cord-like MGHL
Describe a sublabral foramen
Labral anatomic variant where the labral is not attached anterosuperiorly. (often mistaken for a SLAP tear)
Can be differentiated from SLAP tear because slap tears will usually continue posteriorly to involve the biceps anchor.
Name 2 types of scapular winging and their operative treatment of choice.
Medial winging
from loss of serratus function (Long thoracic nerve)
Treat with Pec major transfer to inferior angle of scapula)
Lateral winging
from loss of traps (spinal accessory nerve)
“Eden Lange” transfer. Levator and rhomboid insertion on scapula osteotomized and transferred laterally.
Position of hemiarthroplasty
GT should be 10mm inferior to top of prosthesis
Top of prosthesis should be 56mm superior to pec major insertion
Retrovert 20-30 degrees
Contraindications to TSA (name 6)
Insufficient glenoid bone stock
RC arthropathy
Large irreparable RC tear
Deltoid dysfunction
Infection
Neuropathic (charcot) joint
Describe the Walch classification of glenoid wear
A1: Minor central erosion
A2: Deep central erosion
B1: Posterior wear
B2: Biconcave glenoid
C: >25 degrees of retroversion
Complications associated with RTSA (list 8)
Neurologic injury
Intraop periprosthetic fracture
Hematoma formation
Scapular notching
Baseplate failure
Instability/dislocation
Infection
Acromial fracture
Indications for RTSA
Pseudoparalysis from cuff arthropathy
Incompetent CA arch
Age >70
Low demand patient
Intact deltoid and sufficient glenoid bone
Proximal humerus fracture
Revision TSA
Biomechanics of RTSA
Medialize and distalize the COR
Valgus angle of humeral component
Inferior tilt of glenosphere (15deg)
(creates longer deltoid lever arm)
