conditions of the elbow and forearm Flashcards
what mvts does the humeroulnar joint do
flexion (biceps, brachioradialis) and extension (triceps)
what mvts does the prox/distal radioulnar joint do
supination (supinator) and pronation (pronator teres)
what are the three main n. of the arm and where do they pass
median (pierces thru pronator teres)
ulnar (comes out of brachial plexus)
radial (pierces thru supinator m.)
what is an ulnar collateral lig sprain caused by and what band is more commonly injured
valgus loading of the HU joint, foosh anterior band (elbow flex past 60° can injure post band too)
what is the carrying angle and how does it affect the risk of a sprain
angle btw humerus and ulna w a straight arm
increased risk of sprain if angle is bigger
UCL sprain is more common in what athletes and in what mvt
in overhead athletes with cocking and acceleration phases = most stress on UCL (pull baseball players out of game bc of overhead mvt but can keep rugby and hockey players in if just medium pain)
s/s UCL sprain
- pain w mvt (swelling pressure will cause pain too, flex=post, extension=ant capsule)
- feeling of potential instability
- pronation and wrist flexors weak
- swelling can be noted- medial and post aspects
- ecchymosis
- ulnar n. involvement (numbness, tingling, burning all the way down to the pinky)
valgus extension overload is a collection of what kinds of forces
tensile (on UCL, ulnar n.)
compressive/shear (radial head and post medial olecranon process)
all caused by UCL laxity
s/s valgus extension overload and what structures will rub if the other side of the joint closes
pain on medial side and radial head
posteromedial and lateral elbow pain
nerve paresthesia
radial head and humerus will rub b. on b. which can also cause a chip of b. to come off and stay stuck in the joint which will lock that jnt
what is a RCL sprain, what is it caused by and is it common
pain and laxity
weakness during pronation, supination (bc RCL attaches to the radial head)
weakness of wrist extensors (all pull on lateral epi; where the RCL is)
more rare bc most positions are shielded from varus stress
what is affected in an anterior capsular ligament sprain, what moi can be seen, where can pain be felt
- can be seen in foosh (hyperextension of the elbow will cause pain)
- pain in cubital fossa w palpation, pain w passive elbow extension at end ROM
- elbow flexors may also be affected (bicep, brachialis and brachioradialis bc they run over that area)
what is medial epicondylitis, what is it caused by and what is another name for it
its an irritation to medial epicondyle, where all of the wrist flexor m. originate (eccentric mvt will pull on epi even more)
caused by:
- repeated, medial tension/lateral compression (valgus forces)
- swift, powerful snapping of the wrist and pronation of the forearm
golfer’s elbow: ecc cnt of wrist flexors by that quick mvt of snapping of wrist
s/s of medial epicondylitis
- swelling, ecchymosis
- tenderness on origin of common flexor tendon (just distal to medial epi; 1-2 cm below along FCR and PT m.)
- pain w flexion and pronation of wrist
- grip decreased (gripping smt will cause pain on medial epi)
- may have n. involvement; ulnar n. (if m. is too tight = will pinch it)
- valgus stress test may cause pain at 20-30°
which one is more micro/macrotrauma out of lat and medial epicondylitis
lat: macro
medial: micro
what is a little league elbow
what becomes vulnerable and what can be done to prevent it
avulsion of the common flexor tendon (attached to it) from medial epicondyle due to tension build up, it’s a bone that can’t keep up with the strength of all the other structures
growth plate becomes vulnerable (inj to that area can stunt growth)
restrict the number of pitches/week (<200, 3-4 innings/game)
what is lateral epicondylitis and what is the other name for it
inflammation or repetitive stresses at the lateral epicondyle (irritates the common origin of the wrist extensor m., extensor carpi radialis brevis=most affected)
repetitive eccentric forces
will cause pain with a reduced strength
tennis elbow bc wrist pushed into flexion and extensors will contract eccentrically
s/s lateral epicondylitis
- pain over lat epi
- decreased grip strength, pain w gripping
- may see swelling, point tenderness over lat epi w palpation
- pain w resisted wrist extension, elbow extension and forearm supination
- possible entrapment of the radial n. (if m. are tight, will find during palpation)
how can you RTP an athlete that has med/lat epicondylitis
adding a foam pad that will change the point of origin of that m.
what is ulnar n. pathology and what are the possible moi
superficial therefore predisposing it to concussive forces
nerves supporting structures are unstable (irritation that can come from many diff areas; pinched at thoracic outlet for example)
moi: may chronically sublux as forearm is flexed (sublux from behind medial epi), subject to traction forces when throwing (valgus), inflammed structures can decrease cubital tunnel leading to compression of the ulnar n.
s/s ulnar n. pathology
- ulnar n. is stretched w elbow flexion and wrist extension
- may complain of decreased sensory and motor function (any m. that the ulnar n. innervates)
- complain of increased symptoms w elbow flexed for extended periods of time (night pain- if elbow flexed)
- burning to medial forearm, pinky/ring finger (elbow flex and wrist ext)
- decreased strength of finger flexors, thumb abductors and the FCU
- numbness on dorsal side; indicates ulnar neuropathy coming from the elbow
- numbness on the palmar side; indicates entrapment in the tunnel of guyon (pinched btw pisiform and hook of hamate)
what are the common places for ulnar n. entrapment
btw the two heads of the FCU
behind the medial epicondyle
musculoskeletal injuries heal __ times ___ than n. injuries
3 times faster
radial n. pathology is most commonly injured with what
deep lacerations of the elbow or secondary to fx of the humerus or radius
what is radial tunnel syndrome (what is it, where is it, s/s)
entrapment of the radial n.
located more distally than lateral epicondylitis
s/s: reproduced w resisted supination, extension of the middle finger
path of the radial n.
lateral arm; thumb, first and second digit
median n. pathology, where is it typically injured
at the distal forearm; pressure as the n. crosses the cubital fossa can put pressure on the median n.
what is the pronator teres syndrome
median n. compressed by the pronator teres, inability to pinch the tip of the thumb and index fingers together
what is the forearm compartment syndrome; what is it caused by and what does it increase the risks of compromising
increased pressure in the palmar, dorsal components of the forearm (bc lots of m., vessels, n. in that small space)
cause by hypertrophy m., hemorrhage (lots of swelling and bleeding will increase pressure), fx to the mid forearm or distal radius , supracondylar area
increases the risk of compromising the circulation (check PMSC) and neurological function (some will cut the skin to release some pressure)
s/s forearm compartment syndrome
- complains of pressure in the forearm
- sensory disruption in the hand/fingers
- decreased muscular strength
- pain during stretching of the m. (more than normal stretch discomfort)
- prolonged/increased intensity, absence of radial or ulnar pulses can lead to; volkmann’s ischemic contracture (tissues start to die bc of lack of nutrients/blood supply)
where can bicep strains occur
midbelly of muscle or distal end of tendon (m. tendon jnt)
bicep ruptures are more common at what age
males 40 and more
tendon degrades w time
moi and s/s of bicep ruptures and strains
eccentric loading of the biceps brachii when elbow is flexed to 90°
- loss of strength of elbow flexion and supination
- chief complaints: immediate pain, pop, loss of elbow flexion
- swelling or ecchymosis
- palpable defect possible
moi and s/s of tricep strains
usually caused by eccentric load of triceps (cte elbow forced into flexion)
possible swelling, ecchymosis, palpable defect
chief complaints: pain w elbow extension, loss of strength
what is the moi for an elbow dislocation
large traumatic force (foosh, increased valgus force): axial load through the forearm w elbow slightly flexed
what is the incidence for a posterior dislocation of the elbow
90%; forearm is displaced posterior or posterolateral to the humerus; olecranon pushed post to humerus (looses groove in elbow)
s/s of elbow dislocated and what needs to be done immediately
onset of rapid swelling, deformity compromised blood vessels and n. reduction ASAP (by trained professional)
what is osteochondritis dissicans of the capitellum (how does it develop and what are the chief complaints)
develops from increased valgus loading compressing the radial head and capitulum w overhead throwing
(gets caught in elbow and blocks ROM like a doorstop)
lat elbow pain that increases w activity
flexion contracture
locking of the elbow (loose body)
what are the two types of olecranon bursitis and what is the diff btw them
subcutaneous bursa; located btw olecranon and skin, typically injured from a traumatic force to the elbow
subtendinous bursa; located btw tricep tendon and olecranon, inflamed due to repetitive stresses applied to a jnt
what are the two possible moi for olecranon bursitis
acute or chronic : fall on flexed elbow, constantly leaning on elbow-repetitive pressure
s/s of olecranon bursitis
and what needs to be done first
- immediate, tender swollen area (golf ball)
- redness
- pain w mvt of the elbow
- rebound pain (when youb let go of the area, the pressure will go up)
compression wrap first always with a pad on the area too
