Shoulder Flashcards
What are the etiologies of biceps brachii tendinopathy?
Repetitive strain microtrauma
Injury with tendon fiber disruption
Acute to chronic inflammation of tendon and associated synovial tissues
What structures does the biceps brachii tendon run through?
Origin: Supraglenoid tubercle (intra-articular)
Travels in intertubercular groove
Constrained by transverse retinaculum
Joint capsule forms bursa
Synovial tissue surrounds proximal tendon
Insertion: medial tuberosity of proximal radius and adjacent ulna
Signalment for biceps brachii tendinopathy ?
Mature adult dog
Medium and large breeds
Presentation of biceps brachii tendinopathy?
Weight bearing lameness
- chronic, intermittent
- progressive
- worsens with excercise
- unilateral
Painful — maximally flexed shoulder and extended elbow, and on deep palpation over intertubercular groove
Muscle atrophy
Diagnosis of biceps tendinopathy?
Radiographs
— lateral/craniocaudal to rule out other diseases
—cranioproxminal-craniodisoal “skyline” — not commonly used
Arthrogram
Ultrasound
MRI
-cross sectional anatomy of all soft tissues
Arthroscopy gold standard
— lateral/craniocaudal radiographs + arthroscopy
What is the treatment for acute biceps tendinopathy?
Confinement for 4-6weeks
NSAIDS
+/- physical therapy
What is the treatment for recurrent/persistent lameness due to biceps tendinopathy?
Moderate, acute signs
Intraarticular/bicipital tendon sheath infiltrated corticosteroid injection — methylprednisolone acetate
Strict confinement for 4-6weeks
Physical therapy
What are the indications for surgery with biceps tendinopathy?
Refractory to medical therapy
Ruptured biceps tendon
Chronic bicipital tenosynovitis
Moderates to severe lameness
What is the surgical procedure to treat biceps tendinopathy?
Tenotomy of biceps tendon +/- tenodesis of bicipital tendon
Tenodesis —> fixation of the tendon in new location
What is the prognosis for biceps tendinopathy?
Medical treatment — good to poor
Surgical treatment
Tenotomy — excellent results
Tenodesis — good, excellent assisted arthroscopically
What are there support structures of the shoulder joint? Laxity of these structures will lead to shoulder instability.
Medial/lateral glenohumeral ligaments
Joint capsule
Subsapularis tendon (medial)
Teres minor, supra- and infraspinatus (lateral)
Most shoulder instability is (medial/lateral)
Medial (80%)
Signalment and presentation of shoulder instability?
Medium/lg breed
Adult
Active dogs
Variable intermittent lameness
Poor response to rest and NSAIDS
Physical exam finding with shoulder instability?
Muscle atrophy
Pain on manipution of joint
Medial instability
— increased abduction angle
—> normal is 30 degrees
—> abnormal 50 degrees
Compare to contralateral limb!
How do you confirm shoulder instability?
Radiographs — rule out other conditions, may see some degenerative changes
MRI — can underdiagnose severeity
Arthroscopy***
—> diagnostic and therapeutic if PE is supportive
Treatment for shoulder instability?
Mild — REST, PT , hobbles (3weeks post op0
Moderate — arthroscopic radiofrequency shrinkage of attenuated ligaments and joint capsule
—rest, PT, and hobbles
Severe — medial glenohumeral ligament reconstruction (suture anchors or bone tunnels and monofilament nylon)
— velpeau sling (2-4weeks post op)
What are the causes of infraspinatus contracture?
Contracture= shortening of muscle, not caused by active contraction
Acute, traumatic disruption of muscle fibers
Normal muscle is replaced with fibrous tissue
What is the presentation of infraspinatus contracture?
Acute lameness
Nonpainful, non-weight bearing lameness
External rotation of shoulder and internal displacement of elbow
What is the treatment for infraspinatus contracture?
Conservative treatment unhelpful
Tenectomy of infraspinatus tendon
Release of other capsular adhesion
Physical therapy ideal
What is the signalment for traumatic shoulder luxation?
Any age or breed of dog, rare in cats
History of trauma or evidence of injury
Acute onset
What are physical findings consistent with traumatic shoulder luxation?
Non-weight bearing lameness
Pain on palpation of shoulder
Malpositioning of greater tubercle
Medial luxation: distal limb abducted
Lateral luxation: distal limb adducted
T/F: A medial traumatic shoulder luxation means the humeral head is medial to the glenoid
True
Treatment for shoulder luxation ?
Closed reduction
Open reduction + ligament repair
How is a closed reduction done for a shoulder luxation?
Distract limb, move humerus toward glenoid
Stable joint: apply coaptation or 2 weeks
—velpeau sling (medial luxation)
—spica (lateral, crainial, caudal luxation)
