Elbow - Ortho Flashcards
What is the function of the elbow?
To work with the shoulder to position the hand in spance
True or False: the stability of the elbow makes it resistant to over use injuries.
False: Since there is so little give it is very prone to over use injuries
What is the biomechanical function of the elbow?
It is a link in the biomechanical chain that allows for the transfer and dispersement of forces that occur in the upper extremity.
What are the joints of the elbow?
Humeroulna
Humeroradial
Proximal Radioulnar
When the elbow is extended, what is the relationship between the olcronon and the epicondyles?
Points of all three (Lateral eip, olecron, medial epi) will all lie in a straight line.
What is the relationship between the points of the epicondyles and the olectronon when the elbow if flexed. ?
they form an isosceles triangle
If the triangle is uneven than it is likely a sign of an orthopedic problem (ligamentous instability? I am guessing but I think I am right).
what is a Monteggia Fracture?
A fracture of the ulnar bone associated with a dislocation of the radial head.
How are monteggia fractures classified?
By the direction that the radial head dislocates.
What type of monteggia fracture is most common? Which way does it dislocate?
Type 1 (seen in 60% of monteggia fractures.)
The radial head is dislocated anteriorly, with palmar angulation of the fractured shaft of the ulna.
So the head of the raduis and the fractured segment of the ulna both move toward the palmer side of the forarm.
What type of joint is the Humeroulnar Joint?
Uniaxial Hinge Joint
What structures does the humeroulnar joint lie between?
between the trochlear notch of the proximal ulna and the butterfly shaped trochlea of the humerus.
What is the importance of the “carrying angle” of the elbow? what joints are responsible for forming it?
The posterior section of the humeral trochlear grove runs at about a 15 degree angle. This means that when the arms are extended the forearms and hands should be slightly away from the body. This allows for normal movements of the arms when walking or carrying objects.
What is the carrying angle in males and females?
Male: 11-14 degrees
Females: 13-16 degrees
What is the open-packed position of the humeroulnar
joint?
70° of flexion with 10° of forearm supination
What is the close packed-position of the humeroulanr joint?
full extension and maximum forearm supination
What is cubital valgus?
An increased carrying angel.
What MOI is associated with a cubital valgus?
Lateral Epicondylar Fracture.
What % of pediatric fractures are represented by lateral condyle fractures?
15% - 17%
What age are lateral epicondyler fractures most likely to occure?
5-7 years old
Compare Valgus and Varus
These are adjectives that describe the deviation of a distal segment in relationship to its close proximal segment.
Valgus: the distal segment has moved laterally in respect to the proximal segment
Varus: the distal segment has moved medially in respect to the proximal segment.
There is a fracture of the laterally epicondyle. What directional force was likely applied to cause this fracture?
A varus blow (the point of contact is medial and the affects are felt laterally.)
When a cubital valgus forms, what type of fracture was the lateral epicondyler fracture likely to be?
Avulsion
What muscles and ligaments are involved in a lateral epicondyler fracture?
extensor muscles
lateral collateral ligaments
What is the term for a decreased carrying angle?
cubital varus
aka gunstock deformity
What injury is associated with a gunstock deformity?
supracondylar fracture
The problem is less the fracture itself and more the way it is set after. Improper alignment will cause the bones to heal in a manor that leads to the deformity.
What are the most common elbow fractures in children?
Supracondyler (60%) Lateral Conduler (15%) Medial condyler (10%)
What is the MOI for most sypracondylar fractures?
FOOSH injuries with the proximal ulna tranmitting forceto the distal humerus
What joint lies between the capitulum and the concave head of the radius?
Humeroradial joint
How is the humeroradial joint classified?
uniaxial hinge joint
What motion is available at the humeroradial joint?
Flexion, extension, radial rotation.
What is the open-packed position of the humeroradial joint?
extension and forearm supination
What is the closed packed position of the radiohumeral joint?
90° of elbow flexion and 5° of supination
How is the Proximal Radiohumeral joint classifed?
uniaxial pivot joint
What is the open packed position of the radiohumeral joint?
70° flexion and 35°of forearm supination
What is the closed packed position of the radiohumeral joint?
5° of forearm supination
What ligament forms the majority of the articular surface of the proximal radioulnar joint?
The annular ligament (about 80% for the articular surface).
What is the funtion of the annular ligament?
to maintain the relationship between the head of the radius and the humerus and ulna
What causes nursemaids elbow?
AKA pulled elbow
Sudden pull of the hand of a child age 2-5 when the elbow is extended and pronated (long axisis distraction with the childs hand in pronation)
What anatomically happens in nursemaids elbow?
The radial head slips out from under the annule ligament. The ligament then gets trapped in the radiohumeral articulation - dislocation of the radial head
What potentially causes flexion contractures of the elbow?
prolonged immobilization of the elbow
injury of the joint capsule
What is the most common articular disorders?
Osteoathritis
AKA Degenerative Joint Disease
What is the first symptom of DJD?
Pain
What population is most likely to be effected by DJD?
Men and Women Ages 40+
What does DJD primarily effect?
hyaline cartilage and subcondral bone
What joints are most effected by DJD?
Fingers hips knees elbows shoulders cervical and lumbar spine
What is the most important ligament in the elbow for providing stability against valgus stress?
Medial Collateral Ligament
What range of motion is the medial collateral ligament most important in?
20 - 130 degrees of flexion and extention
What are the componanets of the Medial Collateal Ligament?
Anterior Bundle
Transverse Bundle
Posterior Bundle
What is the strongest of the collateral ligaments?
The anterior band of the Anterior Bundle
What is the function of the Anterior band of the Anterior Bundle of the MCL?
Primarily stabilizes the elbow against valgus stress in the ranges of 20-120° of flexion, and becomes a secondary restraint with further flexion.
At what point does the posterior band of the anterior bundle become taut?
55° of elbow flexion
What is the posterior band of the anterior bundle’s funtion?
A primary restraint to passive elbow extension
A secondary restraint to valgus stress at lesser degrees of flexion
An equal co-restraint with the anterior band at terminal elbow flexion
What is Cooper’s ligament?
The transverse bundle of the ulnar collateral ligament (MCL)
What is the origin and insertion of cooper’s ligament?
it both originates and inserts into the ulna.
What makes up the posterior bundle of the MCL?
A thickening of the posterior elbow capsule
What is the function of the MCL?
Provides only secondary restraint to valgus stress at flexion beyond 90°
Describe little leager’s elbow.
Avousion of the medial epicondyle
Seen in overuse injuries to adolescents playing sports the require strong throwing motions
What area of the elbow do throwing motions stress?
The radial humeral articulation. Throwing motions put excessive compression between the capitulum and the radial head.
What is the difference in lymph node presentation between infection and malignant?
Infection = large, soft, tender, mobile Malignant = large, hard, fixed, non-tender, nodular asymmetry
What makes up the lateral collateral ligament?
The annular ligament
The fan-like radial collateral ligament
The accessory collateral ligament
The lateral ulnar collateral ligament
What is the function of the LCL?
maintain the ulnohumeral and radiohumeral joints in a reduced position when the elbow is loaded in supination
What is the main bursa of the elbow?
the olecron bursa
What are the AKA’s for students elbow?
Olecranon Bursitis
Miner’s Elbow
How will a patient with Miner’s elbow present?
elbow held in semi-flexion position
What is the MOI for olecranon bursitis?
1) A fall on the tip of the elbow or a direct blow to the olecranon can cause swelling (synovial fluid,pus, blood) into the bursa or bursae
2) Chronic olecranon bursitis can result from repeated blows to the olecranon as in football, hockey or repeated weight bearing forces
What are the primary flexors of the elbow?
biceps, brachialis, & brachioradialis
What are the weak flexors of the elbow?
pronator teres
flexor carpi radialis (FCR)
flexor carpi ulnaris (FCU)
extensor carpi radialis longus (ECRL)
What is Myositis ossificans?
From the book: An aberrant reparative process that causes benign heterotopic (i.e., ex- traskeletal) ossification in soft tissue.
From the ppt: Traumatic myositis ossificans represents a heterotophic bone formation in the soft tissue
Where does Myositis Ossificans usually occur?
Process occurs most often in muscle but may also occur in fascia, tendons, ligaments, or joint capsules
What causes most myositis ossificans?
local injury sufficient to cause bruising or frank hemorrhage within a muscle
What are the most common sites of myositis ossificans?
brachialis anterior (elbow), quadriceps femoris (thigh), adductor muscles of the thigh, and the medial collateral ligament of the knee
What is Pellergrini-Steida disease?
Myositis Ossificans of the medial collateral ligament of the knee
What is Prussian’s disease
Myositis Ossificans of the adductor magnus of the thigh
What muscles extend the elbow?
Triceps
Anconeus
What muscles pronate the elbow?
Pronator teres
Pronator quadratus
Flexor carpi radialis
What muscle supinate the elbow?
Biceps
Supinator
Where is the cubital fossa?
the triangular space, or depression, located over the anterior surface of the elbow joint, and which serves as an ‘entrance’ to the forearm, or antebrachium
What is contained within the cubital fossa?
The tendon of the biceps brachii lies in the central structure in the fossa
The median nerve
The brachial artery
The radial nerve
The median cubital or intermediate cubital cutaneous vein
What muscles are located in the anterior compartment of the forearm?
Pronator Teres Flexor Carpi Radiali Palmarsis longug Flexor Digitorm superficialis Flexor digitorm produndus flexor pollicis longus flexor carpi ulnaris pronator quatratus
What muscles are located in the posterior compartment of the forearm?
Abductor pollicis longus extensor possicis brevis extensor pollicis longus extensor digitorm communis extensor digitorm proprius extensor digit quinti extensor carpi ulnaris
What muscles make up the moble wad of 3?
Brachioradialis
extensor carpi radialis longus
extensor carpi radialis brevis
What muscles and nerves are responsible for supination of the elbow?
Suppinator - posterior interosseous (from radial) = c5-c6
Biceps brachii - Musclocutenous = c5c6
What muscles and nerves are responsible for pronation of the elbow?
Pronator Quadratisu - anterior interossious (from median) = c8t1
Pronator Teres - median = c6c7
Flexor Carpi Radialis - median = c6c7
Where is the radial tunnel located?
anterior aspect of the radius
beginning proximal at the radiohumeral joint, and ending where the nerve passes deep to the superficial part of the supinator muscle
What could “snapping elbow” indicate?
dislocation of the ulnar nerve movement/dislocation of the medial head of triceps muscle or tendon over the medial epicondyle as the elbow is flexed or extended loose bodies (often seen with locking) inside the joint synovitis inside the joint
What are the three major deep tendon reflexes of the
elbow?
biceps, brachioradialis and the triceps reflex
What is more common: MCL or LCL damage
MCL instability is found found 4-7x more frequently than LCL instability.
Which test is a valgus test of the elbow? which is a varus test of the elbow?
Valgus = MCL laxity = Medial Collateral ligament test/ABduction stress test Varus = LCL laxity = Lateral Collateral Ligament test/ADDuction stress test
What causes tennis elbow?
Repetitive tension overload at the forearm and wrist.
What is the primary muscle associated with tennis elbow?
Extensor carpi radialis brevis muscle/tendon
What are the symptoms of tennis elbow? What is palliative and provocative?
Aching or burning pain in region of lateral epicondyle (tennis elbow is the AKA for lateral epicondylitis)
Rest = palliative Activity = exacerbated
What are the tests for lateral epicondylitis?
Cozen Test Mills Test (maneuver)
What activities can lead to medial epicondylitis?
Any activities that stress the flexor muscles of the forearm can cause symptoms of golfer’s elbow.
eg golf swing, throwing, chopping wood with an ax, running a chain saw, and using many types of hand tools
What test checks for medial epicondylitis?
Golfer Elbow Test
What is thrower’s elbow?
Wearing out of the MCL due to overuse –> leads to a sprain of the MCL.
Where does pain refer to the elbow from?
Cervical spine
Wrist
Hand
What are the intervention phases for the shoulder?
Acute Phase
Functional Phase
What are the goals of the acute phase of care?
Protection of the injury site
Restoration of pain-free range of motion in the entire kinetic chain
Improve patient comfort by decreasing pain and inflammation
Retard muscle atrophy
Minimize detrimental effects of immobilization and activity restriction
Maintain general fitness
Patient to be independent with home exercise program
What are the goals of the functional phase of care?
Attain full range of pain free motion Restore normal joint kinematics Improve muscle strength to within normal limits Improve neuromuscular control Restore normal muscle force couples
