surgery of the elbow II

Question 1

why has elbow replacement sx been abandoned?

Answer 1

high complication rates

Question 2

what is UAP

Answer 2

ununited anconeal process, anconeal process does not form bony union with proximal ulnar metaphysis

Question 3

when does anconeal process fuse to ulna

Answer 3

not until 4-5 months old, diagnosis of UAP cannot be made until after that age

Question 4

UAP signalment

Answer 4

GSD overrepresented

Question 5

best radiographic views for UAP imaging

Answer 5

flexed lateral brings anconeal process into view, oblique craniocaudal view

Question 6

describe UAP radiographs

Answer 6

radiograph both elbows, UAP visible and lucent indistinct line, best viewed on flexed lateral view, concurrent FCP can occur

Question 7

what is this diagnostic for

Answer 7

lucent irregular line between anconeal process and olecranon, subchondral bone sclerosis - UAP

Question 8

what are 5 principles of medical management of UAP

Answer 8

weight management, nutritional supplement, exercise moderation, PT, anti-inflammatories

Question 9

what is surgical removal of anconeal process

Answer 9

standard tx if UAP dx before onset of DJD

Question 10

what is the outcome of surgical reduction and lag screw fixation of UAP

Answer 10

outcome not uniformly successful due to implant failure

Question 11

what is ulnar osteotomy

Answer 11

relieves pressure on anconeal process allowing healing in immature dogs

Question 12

which surgeries may be used concurrently to tx UAP

Answer 12

ulnar osteotomy and lag screw fixation of anconeal process

Question 13

when is sx recommended for UAP

Answer 13

under 1 year of age with minimal DJD, progressive OA after surgery

Question 14

what is prognosis of UAP surgery with secondary osteoarthritis

Answer 14

guarded

Question 15

what is prognosis of UAP sx if <1 year

Answer 15

good

Question 16

what is IOHC

Answer 16

incomplete ossification of humeral condyle, not in category of dysplasia but it’s developmental dz

Question 17

define IOHC

Answer 17

failure of bony union between medial and lateral portions of humeral condyle

Question 18

what is the underlying cause of IOHC

Answer 18

unknown

Question 19

when does normal ossification of humeral condyle occur

Answer 19

2 weeks old and complete by 8-12 weeks

Question 20

signalment of IOHC

Answer 20

spaniel breeds

Question 21

what percentage of dogs have bilateral IOHC

Answer 21

90%

Question 22

what is this diagnostic for?

Answer 22

IOHC, fissure line noted by arrow

Question 23

what may IOHC lead to?

Answer 23

IOHC may lead to lateral humeral condylar fracture

Question 24

IOHC PE findings

Answer 24

lameness of one forelimb usually evident

Question 25

how is IOHC detected on rads (what view)

Answer 25

craniocaudal view of elbow joint

Question 26

what is more sensitive that rads in detecting IOHC

Answer 26

CT

Question 27

what may CT show to dx IOHC

Answer 27

new bone formation on lateral humeral epicondyle, increased humeroulnar joint space

Question 28

why is medical management ineffective for IOHC

Answer 28

lesion can lead to complete fx of humeral condyle

Question 29

what is the most describe tx for surgery of IOHC

Answer 29

lag crew fixation, but screw failure due to cyclic loading may occur

Question 30

what can minimize screw failure during lag screw fixation of IOHC

Answer 30

use largest diameter screw

Question 31

what is autogenous cancellous autograft core for IOHC

Answer 31

create a biological bone bridge between medial and lateral condyles

Question 32

what type of procedure is autogenous bone core grafting?

Answer 32

highly advanced procedure

Question 33

describe lag screw fixation of IOHC

Answer 33

use partially threaded cancellous bone screw

Question 34

prognosis for IOHC

Answer 34

lag screw generally results in resolution of lameness post op but breakage can occur months to years post op

Question 35

what is traumatic elbow luxation associated with

Answer 35

blunt trauma of elbow joint causing lateral displacement of radius and ulna

Question 36

what do young animals have with traumatic elbow luxation

Answer 36

physeal fractures

Question 37

what does elbow trauma result in?

Answer 37

rupture or avulsion of collateral ligaments, allows luxation of radius and ulna

Question 38

how do the radius and ulna luxate with traumatic elbow luxation

Answer 38

laterally

Question 39

in severe elbow luxation injuries, what can rupture?

Answer 39

origins of extensor or flexor muscles ruptures

Question 40

what does chronic elbow luxation result in

Answer 40

chondromalacia, articular cartilage destruction, secondary DJD

Question 41

how are most luxated elbows managed

Answer 41

reduced by closed manipuation if tx within a first few days

Question 42

how are avulsion fx with elbow luxations managed

Answer 42

open reduction and stabilization

Question 43

what is the objective during manual reduction of elbow luxation?

Answer 43

hook anconeal process between condyles

Question 44

what technique is used to facilitate closed reduction of elbow luxation

Answer 44

indirect reduction using animal's own weight in tib/radial fractures - suspend fractured limb from ceiling

Question 45

when is a closed reduction of luxated elbow attempted

Answer 45

ASAP

Question 46

what is carefully evaluated after elbow luxation reduction

Answer 46

stability of elbow

Question 47

what is the response to trauma of the elbow

Answer 47

DJD and decreased ROM

Question 48

what is the prognosis of elbow luxations if quickly reduced and stabilized

Answer 48

good

Question 49

how do you perform a closed reduction of luxated elbow

Answer 49

hook anconeal process into olecranon fossa, abduct and outwardly rotate antebrachium

Question 50

excessive instability of joint indicates need for what

Answer 50

open stabilization of joint tissue

Question 51

how is open reduction of luxated elbow performed

Answer 51

replace collateral ligaments using 2 screws and figure 8 wire and use lag screw with spiked washer

Question 52

describe arthrodesis of elbow

Answer 52

make 2 osteotomies and remove portion of proximal ulna, add contour plate to caudal surface of humerus and ulna

Question 53

what two syndromes are grouped under elbow subluxation or incongruity?

Answer 53

1: part of pathophysiology of premature closure of distal ulnar or radial physes 2: in chondrodystrophic breeds caused by asynchronous growth of radius and ulna

Question 54

what does elbow incongruity contribute to

Answer 54

FCP and UAP

Question 55

when is an ulnar lengthening osteotomy indicated

Answer 55

when cause of elbow incongruity is ulna too short

Question 56

when is an ulnar shortening ostectomy or radial lengthening osteotomy performed

Answer 56

when radial shortening has caused subluxation of humeroradial joint

Question 57

how is radial lengthening performed

Answer 57

distraction osteogenesis using circular external fixator

Question 58

what is etiology of congenital elbow luxation

Answer 58

unknown

Question 59

describe congenital elbow luxation

Answer 59

bone malposition at young age, congruent joint surfaces don't form, 3 months old = degenerative changes develop

Question 60

signalment of congenital elbow luxation

Answer 60

small breeds, unilateral or bilateral, 3-6 weeks of age

Question 61

what is an important consideration of congenital elbow luxation surgery

Answer 61

limited ROM and DJD even with surgery