53.elbows Flashcards
normal ROM, flexion and extension of elbow
ROM 130 degreesextension 165flexion 36(labradors)
Campbells test
with the elbow and carpus in 90 degree FLEXION primary stabilization for rotation is through MCL (generally weaker than the LCL)Campbell tests the integrity of the MCL
what orientation are 90% of traumatic elbow luxations
LATERAL luxationsthe distal slope of and large medial humeral trochlea prevents medial luxation LCL is stronger than MCL
type of elbow luxation associated with radial head luxation
Monteggia fracture1. most frequent; cranial lux of radial head and cranioproximal ulnar fracture2. caudal lux radial head and caudal angulation of ulnar fx3.lateral lux radial head4. fracture of proximal radius and ulnar diaphysis with cranial lunation of radial head
dogs and cat species difference in collateral ligament damage and traumatic elbow luxation
cats: both medial and lateral collateral ligaments must be damaged in order to see lunationdogs: at least lateral collateral ligament must be damaged to have luxation
characteristic limb position in dog with elbow luxation
NWBantebrachium abduction and externally rotated with elbow in slight flexion
sx repair for elbow lux
indicated for chronic fracture, failure of closed reduction, intraarticular fx or avulsion fx present1. reduce2. collateral ligament reconstruction +/- prosthetic repair with nonabsorbable suture and bone anchors/screws with washers, transverse bone tunnels (at humeral epicondyle and radial neck). transcondylar/transradial/transulnar bone tunnel for biaxial suture placement3. joint immobilization: spica splint, modified ESF, flexible ESF 2-3 weeks
types of congenital elbow luxations
uncommon1. lateral or caudolateral dislocation of radial head with the ulna in a relatively normal position2. MOST COMMON; disruption of humeroulnar with lateral rotation and sublux of ulna +/- radial head3. luxation of radius and ulna; often in poluarthrodysplastic dogs
what is a modified bell-tawse procedure to treat chronic congenital elbow joint luxation
- approach craniolateral elbow2. radial ostectomy and counterclockwise rotation of proximal radius with bone plate stabilization3. reconstruct annular ligament with extensor carpi ulnaris muscle4. joint immobilization with transarticular Kwire
options for sx repair for congenital elbow luxation
- radial head ostectomy2. Bell Tawse procedure3. arthrodesis4. limb amputationJOINT REPLACEMENT IF A CONTRAINDICATION WITH CONGENITAL ELBOW LUX
signalment for dogs with elbow dysplasia
young large-giant breed dogs17% labs70% bernese mountain dogsbilateral in 35% (25-80%); MULTIfactorial; male 2:1FCP or MCP, UAP, OC/OCD, RUI(ununited medial epicondyle is not included YET but may be a component in medial compartment disease)
T/Fthe anconeal process in small breed dogs does not have a separate center of ossification
TRUEsmall dogs–not a separate center of ossificationlarge dogs (GSD)–separate center of ossification (should fuse by 5 months GSD)diagnosis should not be made until weeks 22-24
most common cause of asynchronous growth in the antebrachium
damage to distal ulnar physis
treatment of UAP
- nothing leads to progression of OA (usually faster and more severe than other components of elbow dysplasia)2. lag screw or Kwires3. excision (90% owner satisfied only 50% dogs free of lameness)4. address RU incongruity: ulnar osteotomy 30-60 mm distal to radial head caudoproximolateral craniodistomedial oblique +/- ulnar pin to prevent tipping +/- surgical reattachment of anneal process
distal humeral 3 ossification centers
trochlea, capitulum and medial epicondyletrochlea and capitulum fuse together at 3 monthstrochlea and capitulum fuse to metaphysis at 6 monthsmedial epicondyle should fuse to condyle at 6 months