29 - Upper Extremity Injury Flashcards
What are the three mechanisms of a fracture?
Acute: from suddent impact of a large force exceeding strength of the bone
Stress: from repetitive submaximal stresses
Pathologic: from normal forces to diseased bone
What is the fracture history seen with an acute or chronic fracture?
Acute: sudden blow
Chronic: repeitive activity, increase in activity duration, intensity, or frequency. Pathologic bone.
What are the components of a fracture exam?
Deformity: bleeding +/- fragement = suspect open fracture = orthopaedic emergency needs to be surgically washed out.
Bony point tenderness
Bone pain with loading- indirect loading esp. useful.
What are some indirect loading tests?
Axial loading - pushing in on the limb or digit
Bump test - bumping the injured limb to test for pain
Fulcrum test - stablize proximal part and push down on the distal part, break will be loaded and cause pain
Hop test - hopping to elicit pain
What are some ways to diagnose a fracture? What are fracture treatments?
- Plain Xrays
- CT
- Bone scan
- MRI
Treatment: immobilization, avoidance of NSAIDs - some animal model studies show they interfere with bony healing via PGs
What are some bones with “vulnerable” blood supply?
Watershed regions: central (tarsal) navicular bone
Retrograde supply: scaphoid, talus, femoral head
What are the contents of the anatomical snuff box?
- Radial nerve
- Cephalic vein
- Radial artery
- Scaphoid bone
What causes scaphoid fractures? What are clinical findings and what occurs?
Usually a fall on out-stretched hands (FOOSH) - fractures of middle third (waist) of scaphoid most common
Findings: pain, tenderness, and swelling of snuff box
Because nutrient arteries only enter the distal half, fracture often causes necrosis of the proximal portion.
What is the initial treatment of a scaphoid fracture?
Immobilize with a splint.
What is a non-union risk factor for bone healing?
Tobacco use: can lead to poor healing of a fracture.
What are three types of musculotendinous injuries? Describe each.
Enthesopathy: disorder of muscular or tendinous bony attachment
Tendinitis: technically acute inflammation of tendon; traumatic blow or pull
Tendinosis: chronic degenerative condition of tendon (chronic - submaximal repetitive irritation)
*Many injuries may be acute on chronic.
What are enthesopathies? What are examples?
Disorders involving ligamentous or tendinous attachment to bone
Epicondylitis (elbow) and shin splits
Pain with stressing structures and to palpation.
What is delayed onset of muscle soreness (DOMS)? When does it occur and why?
Weakness, tenderness, and elevated muscle enzymes about 24-72 hours after unaccusromed physical activity.
Lasts ~5-7 days
Caused by disruption of the sarcolemma, resulting in influx of intracellular Ca2+ which causes proteolytic enzyme mediated myoprotein degradation.
What is a strain? What are symptoms?
Muscle fiber damage from over-stretching: eccentric loading (muscle lengthening during firing)
Symptoms: stiffness, bruising, swelling, soreness, and weakness (with more severe injury).
A 60 yo retired assembly line worker complains of shoulder pain with overhead motions. On exam, he has pain with over 80 degrees of abduction and weak external rotation. What testing should be done?
“impingement testing”
Empty can testing: bring arms out and turn them over (like your flipping a can over)
Hawkins test: stabilize elbow and have them push arm up againt hand
Neers test: swinging their arm over their head
Children don’t get enthesopathy, they get ________. Why is this?
If a golfer has pain upon wrist extension, what type of epicontilitis do they have?
Lateral epicondylitis; the extensers of the wrist have a common attachment there.
What are enthesopathies? What are examples?
Disorder involving ligamentous or tendinous attachment to bone
Exp: epicondylitis, shin splints, pain with stressing structures and to palpation.
What type of exercise is most likelu to cause a muscle strain?
An eccentric exercise because it puts the most stress on the muscle/tendon.
Exp: quadriceps on landing a jump
What is true about the timing of rotator cuff tear repair?
If the patient has an acute tear, surgery shuld be done sooner rather than later.
Otherwise the muscle will scar down; surgical window is like 1-2 months.
What are swome clinical characteristics of someone with a rotator cuff tear?
Struggling to abduct their arm to 90 degrees.
Can’t initiate because supraspinatus is torn.
What is the etiology of an acromioclavicular (AC) sprain? What would you see on exam?
Most commonly due to a fall directly onto shoulder.
Pts presents with pain with overhead motions, deformity of superior shoulders.
On exam: pain and deformity at AC joint, pain with cross body adduction of arm (positive cross-chest test), and painful arc of abduction over 150 degrees.
Describe the grading of an AC injury?
Grade I: AC ligament injury (stretching)
Grade II: AC ligament tear and oracoclavicular (CC) ligament stretch
Grade III: complete tears of both AC and CC ligaments.
What is a sprain?
Ligamentous damage from overloading.
Symptoms: instability or laxity; swelling
Describe the stages of bony healing?
Bleeding, clot formation, inflammatory stage.
Repair:
- osteoclasts/blasts invade clot
- Soft callus forms (2-6 weeks)
- Hard callus (4-12 weeks)
- Callus matures (6-12 mo)
- Bony gaps bridges (6-12 months)
Remodeling occur sin 1-2 years
What should you think of when a patient complains of “locking” or “catching” of their knee?
Loose body (aka joint mice): cartilage fragment that has gotten caught in the joint.
What is a Maisonneuve fracture? What test can idenfity this?
When a force radiates upwards to the head of the fibula causing a fracture in the head/neck of the fibula.
Squeeze test: squeeze middle of leg to make ends of bone bow. If maisonneuve fracture is present, this test will elicit pain.
What test should rule out a high ankle sprain?
The external rotation test: external rotation of the foot should NOT hurt a lateral ankle sprain.
90% of shoulder dislocations occur in what direction? These can affect which nerve?
Anteriorly
Axillary nerve: traverses the quadrangular space and wraps around the neck of the humerus.
What is capsulitis? What history is often seen?
Capsular thickening, inflamamtion, scarring; Idiopathic or post-injury.
Limited ROM
- painful eary with decrease ROM (freeze phase)
- non-painful with stable, decreased ROM (frozen phase)
- non-painful with improving ROM (thawing phase)
What are the type of 5th metatarsal fracture?
Avulsion: base @ peroneus brevis insertion
Jones: traumatic fracture metaphyseal-diaphysis junction
Pseudojones: stress fracture proximal diaphyseal
Dancer’s: spiral fracture mid to distal diapysis
What is Sever’s condition?
Pain on heel in active children - due to the relative weakness of the growth plate compared to the tendon
If it was a 19yo this would have been achilles tendinitis - in adolescence you see sever’s disease
