Flexural and Angular Deformities

Question 1

What is a flexural deformity?

Answer 1

Hyperflexion of a limb and results from disparity in length of the musculotendinous unit relative to bone length

Question 2

What are the attachments of the superior check ligament?

Answer 2

Attaches from superficial digital flexor to the mid radius

Question 3

What are the attachments of the inferior check ligaments?

Answer 3

From deep digital flexor tendon to the proximal end of metacarpal

Question 4

What are causes of congenital deformities?

Answer 4

Uterine malposition 
Genetics 
Teratogenic agents 
Mare nutrition 
Viral/bacterial infection in mare 
Mare goiter 
Sudan grass ingestion

Question 5

At what joints are flexural deformities usually located?

Answer 5

Fetlock and carpus

Coffin joint is rare

Question 6

What tendons are involved in flexural deformities?

Answer 6

SDF
DDF
Suspensory lig
Joint capsule

Question 7

What are conservative methods for treating a carpal flexural deformity?

Answer 7

Exercise — stretching of tendons
Shoeing — toe extensions (pushes the fetlock back)
Splints
Oxytetracycline —> binds Ca leading to muscle relaxation
Cast

Question 8

What are clinical signs of digital hyperextending?

Answer 8

Toe elevated from the ground

Skinking fetlock

Question 9

What type of shoe could you use for conservative management of digital hyperextension?

Answer 9

Shoe with extended heel —-> support the back

Question 10

What is the surgical procedure for correction of bilateral contracted tendons?

Answer 10

Digital flexor tenotomy

Question 11

What is the prognosis for a digital flexor tenotomy?

Answer 11

Usually good

Full recovery in 2weeks

Question 12

What can cause an aquired flexor tendon laxity?

Answer 12

OCD 
Arthritis (septic)
Wounds 
Trauma 
—> all causing pain 

Prolonged external coaptation

Question 13

How does prolonged external coaptation lead to tendon laxity?

Answer 13

Immobilization

Weakening of soft tissue supporting structures —> articular and tendon laxity
Rapid in foals

Question 14

Common sites for acquired tendon laxity?

Answer 14

Metacarpophalangeal joint (fetlock)

Distal interphalangeal joint (coffin)

Question 15

T/F: flexor tendon rupture looks similar to tendon laxity

Answer 15

True

Both have raised toes and dropped hocks

Question 16

How does a flexor tendon rupture appear and what might be another ddx for this?

Answer 16

Flexion at hock —dropped forward

Radial nerve paralysis —> knuckling

Question 17

What surgical methods can be used to treat extensor tendon rupture ?

Answer 17

Superior check ligament desmotomy

—> removes stress from SDFT to the muscular portion

Question 18

What is another name for contracted tendons causing deformity at the distal interphalangeal joint?

Answer 18

Club-foot

Question 19

What is the cause of club foot?

Answer 19

Fast growing foals
Bone grows faster than tendons

Pain

Question 20

Clinical signs of club-foot?

Answer 20

“Boxy” appearance
Growth at hells
Break in hoof pastern angle
Weight bearing on toe

Question 21

Treatment for club foot?

Answer 21

Controlled exercise
Reduce food intake
Trim heel toe extension

Inferior check ligament desmotomy

Question 22

Surgical treatment of a extensor tendon rupture is ______________ and the treatment for club foot is __________

Answer 22

Superior tendon desmotomy; inferior check tendon desmotomy.

Question 23

What is an angular deformity?

Answer 23

Postural deformities in the frontal plane of the limbs

Question 24

What do you call a lateral deviation of the limbs?

Answer 24

Valgus

Question 25

What do you call a medial deviation of the limbs

Answer 25

Varus

Question 26

What are causes of articular deviation ?

Answer 26

``` Periarticular laxity Incomplete ossification of carpal bones Hypothyroidism Limb confirmation —overloading —Physeal (trauma/infection) Twins ```

Question 27

How can you diagnose angular limb deformities?

Answer 27

Observation Limb manipulation Radiographs

Question 28

What joints can be affected by angular limb deformities?

Answer 28

Carpus Tarsus Metacarpophalangeal or metatarsophalangeal

Question 29

What are the locations of “pivot points” in angular deformities?

Answer 29

Growth plate | Joint space

Question 30

How can you analyze the pivot point ?

Answer 30

Radiograph limb Cellulose acetate overlay —> trace bone outlines Bisect the long bone axis OR Place lines through joint space Measure angle

Question 31

What are conservative treatments for angular limb deformities?

Answer 31

``` Stall rest Hoof trimming External support —splint —cast ```

Question 32

What are the 3 possible surgical treatments for angular limb deformities?

Answer 32

Hemicircumferential periostal transection and elevation (periosteal stripping) ``` Growth retardation (temporary transphyseal bridging) —screws/wires/staples ``` Corrective osteotomy

Question 33

When is corrective osteotomy indicated for angular deformities?

Answer 33

In animals over a year.. no more growth occurring.. Cannot stimulate or decrease growth by other methods

Question 34

What type of shoes can help fix angular deformities?

Answer 34

Dalmer shoes Contain extensions laterally or medially

Question 35

What surgical method accelerates growth at the physis?

Answer 35

Hemicircumferential periostal transection and elevation (periosteal stripping)

Question 36

What surgical method inhibits growth at the physis?

Answer 36

Transphyseal bridging —screws and cerclage wire —staples