Flexural and Angular Deformities Flashcards
What is a flexural deformity?
Hyperflexion of a limb and results from disparity in length of the musculotendinous unit relative to bone length
What are the attachments of the superior check ligament?
Attaches from superficial digital flexor to the mid radius
What are the attachments of the inferior check ligaments?
From deep digital flexor tendon to the proximal end of metacarpal
What are causes of congenital deformities?
Uterine malposition Genetics Teratogenic agents Mare nutrition Viral/bacterial infection in mare Mare goiter Sudan grass ingestion
At what joints are flexural deformities usually located?
Fetlock and carpus
Coffin joint is rare
What tendons are involved in flexural deformities?
SDF
DDF
Suspensory lig
Joint capsule
What are conservative methods for treating a carpal flexural deformity?
Exercise — stretching of tendons
Shoeing — toe extensions (pushes the fetlock back)
Splints
Oxytetracycline —> binds Ca leading to muscle relaxation
Cast
What are clinical signs of digital hyperextending?
Toe elevated from the ground
Skinking fetlock
What type of shoe could you use for conservative management of digital hyperextension?
Shoe with extended heel —-> support the back
What is the surgical procedure for correction of bilateral contracted tendons?
Digital flexor tenotomy
What is the prognosis for a digital flexor tenotomy?
Usually good
Full recovery in 2weeks
What can cause an aquired flexor tendon laxity?
OCD Arthritis (septic) Wounds Trauma —> all causing pain
Prolonged external coaptation
How does prolonged external coaptation lead to tendon laxity?
Immobilization
Weakening of soft tissue supporting structures —> articular and tendon laxity
Rapid in foals
Common sites for acquired tendon laxity?
Metacarpophalangeal joint (fetlock)
Distal interphalangeal joint (coffin)
T/F: flexor tendon rupture looks similar to tendon laxity
True
Both have raised toes and dropped hocks
How does a flexor tendon rupture appear and what might be another ddx for this?
Flexion at hock —dropped forward
Radial nerve paralysis —> knuckling
What surgical methods can be used to treat extensor tendon rupture ?
Superior check ligament desmotomy
—> removes stress from SDFT to the muscular portion
What is another name for contracted tendons causing deformity at the distal interphalangeal joint?
Club-foot
What is the cause of club foot?
Fast growing foals
Bone grows faster than tendons
Pain
Clinical signs of club-foot?
“Boxy” appearance
Growth at hells
Break in hoof pastern angle
Weight bearing on toe
Treatment for club foot?
Controlled exercise
Reduce food intake
Trim heel toe extension
Inferior check ligament desmotomy
Surgical treatment of a extensor tendon rupture is ______________ and the treatment for club foot is __________
Superior tendon desmotomy; inferior check tendon desmotomy.
What is an angular deformity?
Postural deformities in the frontal plane of the limbs
What do you call a lateral deviation of the limbs?
Valgus
What do you call a medial deviation of the limbs
Varus
What are causes of articular deviation ?
Periarticular laxity Incomplete ossification of carpal bones Hypothyroidism Limb confirmation —overloading —Physeal (trauma/infection) Twins
How can you diagnose angular limb deformities?
Observation
Limb manipulation
Radiographs
What joints can be affected by angular limb deformities?
Carpus
Tarsus
Metacarpophalangeal or metatarsophalangeal
What are the locations of “pivot points” in angular deformities?
Growth plate
Joint space
How can you analyze the pivot point ?
Radiograph limb
Cellulose acetate overlay —> trace bone outlines
Bisect the long bone axis
OR
Place lines through joint space
Measure angle
What are conservative treatments for angular limb deformities?
Stall rest Hoof trimming External support —splint —cast
What are the 3 possible surgical treatments for angular limb deformities?
Hemicircumferential periostal transection and elevation (periosteal stripping)
Growth retardation (temporary transphyseal bridging) —screws/wires/staples
Corrective osteotomy
When is corrective osteotomy indicated for angular deformities?
In animals over a year.. no more growth occurring..
Cannot stimulate or decrease growth by other methods
What type of shoes can help fix angular deformities?
Dalmer shoes
Contain extensions laterally or medially
What surgical method accelerates growth at the physis?
Hemicircumferential periostal transection and elevation (periosteal stripping)
What surgical method inhibits growth at the physis?
Transphyseal bridging
—screws and cerclage wire
—staples
