quickster2008's version from 2016-01-14 03:55

Section 1

Section 2

Question Answer
What is the accepted mechanism of injury for a l't MTPJ dislocation?Hyperextension force of the phalanx-sesamoid apparatus on the metatarsal.
Describe closed reduction for a dislocated lSI MTPJ.Distraction of toe, exaggerated dorsiflexion followed by lorced plantarflexory relocation.
A patient presents with a dislocated 151 MPTJ. Radiographs reveal dorsal dislocation of the proximal phalanx and a normal sesamoid-to-sesamoid relationship with both sesamoids dorsal to the metatarsal. What type of reduction would most likely be required? Open reduction. The soil tissue around the joint maintains the position, and closed reduction is virtually impossible for this type of injury.
Describe the location of the true Jones fracture?Located at the proximal diaphysis ofthe 5th metatarsal. It is supra articular.
I f plain radiographs are unequivocal and you still suspect Lisfranc dislocation, what radiologic study would be indicated?Stress abduction views.
Describe the intrinsic stability of Lisfranc's joint.Tarsometatarsal joints form a bony arc from medial to lateral with extensive ligamentous support and the "keystone" nature ofthe 2nd metatarsal in which it is recessed at its base.
What are the two mechanisms postulated for tarsometatarsal joint injury?Direct and indirect. Direct is crushing force on the dorsum of the foot. Indirect usually with forced forefoot plantarflexion and forefoot abduction of the foot. (Can be associated with forced forefoot dorsiflexion as well.)
What is the radiographic sign that is a pathognomonic indicator of nonunion'?Sclerosis of the fracture ends.
What is the difference between a delayed union and a nonunion'?time. nonunion shows NO PROGRESSIVE healing at a fx site after 9 months while a delayed union is defined as a fx site in which healing has not advanced at the average rate for the location and type of fx
What are the two basic categories of nonunions seen radiographically?Atrophic (avascular) and Hypertrophic (vascular). Hypervascular also divided into elephant foot, horse foot and oligotrophicbasedontheamountofcallusformation. Avasculardividedintotorsionwedge,comminuted,defect and atrophic.
An electric bone stimulator would most likely be beneficial for what type of nonunion as a primary form of treatment without surgical intervention.Hypertrophic (vascular),
How is an atrophic nonunion treated?Surgery to debride the fracture ends and a bone graft is inserted with fixation. A bone stimulator can also be applied along with cast immobilization.
What is a pseudoarthrosis?A false joint formed at fracture site due to continued movement without proper immobilization.
What are the four phases in the initial assessment of a trauma patient? Primary survey (Injuries that threaten life or limb are identified), Resuscitation (These life threatening injuries are treated), secondary survey (A systemic, in-depth evaluation ofthe patient from head to toe is performed with continuous reassessment o f the patient's condition) and definitive care (Less serious injuries are managed).
Discuss the primary survey when dealing with a trauma patient.ABC's: A Airway maintenance is first step in trauma treatment. B Breathing, C = Circulation with hemorrhage control (major concern is shock), D Disability (assess neurologic status) and E = Exposure - completely undress patient and examine entire body.
When maintaining an airway in a trauma patient, what must you assume until proved otherwise?Cervical spine injury until proved otherwise - do C-spine control.
Describe the recommended rewarming process that should be performed for a patient with frostbite.Rewarming should be done rapidly in water that is 38-44 degrees C (l00 to 110 degrees F) for 15-20 minutes (up to 45 minutes if necessary). This is often painful and pain medications are often needed.
What is the role of surgical debridement in frostbite injuries?It is difficult to assess the depth and extent of tissue injury so it is best to avoid early surgical debridement and instead allow the tissue to demarcate over several months. Amputations can then be performed. I f infection and wet gangrene is present, however, early surgical intervention is necessary.
What are the two types of epiphyses?Pressure epiphysis - located at ends oflong bones and transmit pressure through the joint. They provide for longitudinal growth. Traction epiphysis or apophysis are sites of muscle/tendon attachment and are non-articular. These do not contribute to the longitudinal growth ofbone.
Describe the physis.This is a radiolucent cartilaginous plate located between the metaphysis and epiphysis in a long bone.
What is the Thurston-Holland sign?This is also known as a "flag sign" and is seen in Salter Harris type II fractures in which a pattern with a triangular shaped metaphyseal fragment is created.
Which Salter Harris injuries are considered intraarticular?Type III and Type IV.
What is compression syndrome?Clinical entity resulting from elevated tissue pressure in a closed spaee confined by osseous and fascial structures. As the pressure increases, it compromises capillary blood perfusion that is needed for tissue viability. This leads to ischemia.
What is the most common compartment in the leg involved in compartment syndrome?Anterior compartment followed by the deep posterior compartment.
What is the degree of ischemia dependent on when dealing with compartment syndrome'!time
What are the six P's of compartment syndrome? Pain, pressure, paresthesia, paresis, pain with passive stretch, pulses present.
At what pressure intracompartmental pressure would a fasciotomy be considered?Range of30-45 mmHg with clinical symptoms.
Describe the complication of myoglobulinuria in compartment syndrome. Occurs secondary to all the muscle necrosis. This can be fataL
Radiographically, how does one differentiate a fractured navicular tuberosity from a Type II accessory navicular? Accessory navicular is bilateral 90% of the time; the fracture is usually sharp with jagged edges while the accessory navicular has smooth rounded edges.
Describe the usual mechanism of injury for a navicular tuberosity fracture. Usually an avulsion type fracture. When foot is forcibly everted, the posterior tibialis tcndon exerts its force and causes the avulsion.
What is Nutcracker syndrome?Severely displaced navicular tuberosity fracture caused by strong pronatory force will cause compression of calcaneo-cuboid joint producing occasional fracture of the cuboid and/or calcaneus.
Describe the mechanism of injury for a dorsal avulsion fracture of the navicular.Plantartlexion with either inversion or eversion. With PF and eversion, the dorsal tibionavicular ligament (part of deltoid) avulses dorsal cortex ofnavicular bone at its insertion. With PF and inversion, the talonavicular ligament becomes stressed and avulses the dorsal cortex.
Are dorsal lip (avulsion) fractures usually intra or extra-articular?Usually intraarticular because they contain articular cartilage.
Radiographically, there is an avulsion fracture at the medial aspect ofthe medial cuneiform. What is the most likely cause of this injury?Tibialis anterior.
What is the most commonly involved articular surface affected in calcaneal fractures?Posterior facet of calcaneus.
What structures are commonly impinged with lateral displacement of a calcaneus fracture.Peroneal tendons.
What is Mandor's sign?Hematoma and bruising that extend to the sole ofthe foot. This is common with calcaneal fractures and some consider it pathognomonic.
What angles must one measure when evaluating a calcaneal fracture?Bohler's angle and the crucial angle of Gissane.
What does an abnormal crucial angle of Gissane suggest'?Abnormal relationship ofthe posterior facet to the anterior and middle facets is present.
What study would be best performed to determine the extent of an intraarticular calcaneal fracture?CT scan
What radiographic view would be best to visualize a fracture of the anterior process of the calcaneus?Medial oblique view.
What structure most commonly causes the avulsion of the anterior process of the calcaneus?Bifurcate ligament.
What is the most common mechanism of injury for an anterior superior calcaneal fracture?Plantarflexion and inversion ofthe foot.
What are the two basic types of intraarticular calcaneal fractures?Tongue type and joint compression.
how are intraarticular calcaneal fractures(tongue type and jt compression) differentiatedThey are differentiated by the location of the secondary fracture line and by the shape of the fragments.
Describe the primary or vertical fracture line in an intraarticular calcaneal fracture.Superior to inferior extending from the vertex of Gissane's angle to the plantar aspect of the calcaneus. This is basically the same for both Tongue type and joint compression fractures.
Ifa patient has fallen from a height, what other injuries must be suspected besides a calcaneal fracture? Lumbar spine, contralateral calcaneus, knees, hips, antebrachium and cranium. Also must suspect internal injury (lacerated spleen or kidney).
What mechanism of injury would most likely cause a medial talar osteochondral lesion'?Inversion ofa plantartlexed foot.
Arthroscopy reveals a shallow, wafer shaped defect in the talar dome after injury. Where would this defect most likely be located on the talar dome and what was the most likely mechanism of injury?Anterior or middle third ofthe talus in the lateral portion. Mechanism most likely was inversion of a dorsit1exed foot.
What is a shepherd's fracture?Fracture of the posterolateral process of the talus. This is also sometimes called a Steida's fracture.
What is the most serious complication following a talar neck fracture?Avascular necrosis.
What is Hawkins' sign?Sign of viability of the blood supply following fracture/dislocation of the talus. There is subchondral bone atrophy due to hyperemia ofthe area ofbone causing bone resorption.
What structure can be confused for a talar lateral tubercle fracture?Os Trigonum.
Status post inversion ankle injury, radiographs reveal an avulsion fracture of the superolateral aspect of the calcaneus? What is the cause of this fracture?Extensor digitorum brevis.
The anterior drawer sign evaluates the integrity of what structure?Anterior talofibular ligament.
Arthrography ofthe ankle reveals dye passing superiorly through the syndesmosis. What does this suggest? Definitive for diastasis.
Arthrography of the ankle reveals dye escaping to the lateral side of the lateral malleolus. What does this suggest?Definitive for a tear of the lateral collateral ligaments.
Mortise views of the ankle reveals increased soft tissue density over the lateral malleolus and a fracture lying parallel to the lateral malleolus. What is your diagnosis?Peroneal subluxation Grade III.
Describe the grades of peroneal subluxation. Grade I - the retinaculum and periosteum are separated from the fibrocartilaginous lip. Grade 11- the fibrous lip was elevated along with the retinaculum. Grade III - a thin fragment ofbone was elevated along with the fibrous lip.
The Lauge-Hansen classification consists oftwo words. What do these words signify?Firstword(eithersupinationorpronation)referstopositionofthefootatthetimeofinjury. Thesecondwordrefers to the direction the talus moves in the ankle mortise.
What is a Tillaux fracture?Avulsion of the tubercle of Tillaux-Chaput (anterolateral margin of the distallibia).
Avulsion of the distal fibula by the anterior inferior tibiofibular ligament is known as what?Wagstaffe fracture.
When should a Volkmann's fracture be fixated?If the fracture is 25% to 30% of the articular surface, fixate it.

Section 3

Question Answer
What is Vassal's principle as it applies to the ankle?When fibular fracture is reduced (correcting length and rotation) this should put the talus back into the mortise in perfect alignment. (This principle doesn't always perfectly reduce the medial malleolus and this usually needs further reduction.)
What is a Maisonneuve fracture?This is a high fibular fracture seen in pronation-external rotation injuries.
What is the function of inversion stress views?Done under anesthesia to determine the presence ofan abnormal talar tilt (5 to 15 degrees is normal).
What are some commonly missed fractures in ankle sprains? Base of the 5th metatarsal, anterior process ofthe calcaneus, Osteochondral dome fracture of talus, High fibular fracture, Posterior lateral distal tibia fracture (can be hidden by fibula), EDB avulsion fracture, and possibly a talar tubercle fracture.
When is an open fracture considered contaminated verses infected?Open fractures are considered infected 8 hours post injury. They are considered contaminated up to this time.
What are the two factors that determine the amount of kinetic energy that a projectile possesses (ie the amount of energy a bullet can deliver to tissue),! Mass and velocity. The formula E=1/2mv2 determines the amount of energy possessed by a bullet.
Discuss the Gustilo and Anderson classification.
Why is the fact that a wound was due to a farm injury such an important consideration?This wound is Clostridial prone and can causc gas gangrene or tetanus.
What is the antibiotic of choice for a type I, type II and type III Gustilo injury?For Gustilo type I and II injuries, a cephalosporin is the drug ofchoice. For a Type III wound, an aminoglyeoside is added to the Cephalosporin to provide gram negative coverage.