Lecture 10 - Common Disorders of the Equine Hind Limb

Cervical spine OA etiology

Trauma; unnatural head carriage; OC

Cervical spine OA clinical signs

Stiff neck; +/- lameness; +/- neurologic signs

Cervical spine OA diagnosis

Radiographs

Cervical spine OA treatment

IA corticosteroids; acupuncture; mesotherapy

Cervical spine OA prognosis

Fair; lifelong maintenance; may progress to neurologic disease

Kissing spines definition

Impinging dorsal spinous processes

Kissing spines etiology

Trauma; poor saddle fit

Kissing spines clinical signs

Pain on palpation; reduced performance; behavior change

Kissing spines diagnosis

Radiographs

Kissing spines treatment

Saddle fit correction; corticosteroid injection; surgical resection

Kissing spines prognosis

Depends on severity

Back muscle pain etiology

Hind limb lameness; poor saddle fit; poor riding; trauma

Back muscle pain clinical signs

Pain on palpation; reduced performance

Back muscle pain treatment

Saddle fit; corticosteroids; mesotherapy; acupuncture; rest

Back muscle pain prognosis

Good once underlying cause addressed

Sacroiliac disease definition

SI arthritis or subluxation ("hunter's bump")

Sacroiliac disease etiology

Trauma; inappropriate use

Sacroiliac disease clinical signs

Acute lameness; crepitus on rectal palpation

Sacroiliac disease treatment

Rest; corticosteroid injection

Sacroiliac disease prognosis

Good; may need maintenance

Most common hind limb lameness region

Hock

Least common hind limb lameness region

Above stifle

MT2/MT4 splint bone fracture etiology

Kick injury; pasture mate; mares

Splint bone fracture diagnosis

Radiographs; non-healing wound

Splint bone fracture treatment

Segmental or complete ostectomy (MT4 only)

Splint bone fracture prognosis

Excellent

Hock lameness gait

Drags toes; fails to track up; adducts limb; reduced performance

Hock lameness palpation

Bone spavin = hard swelling; bog spavin = effusion

Hock lameness diagnosis

Flexion tests; blocks; radiographs; scintigraphy; CT

Hock OA name

Bone spavin

Hock OA most affected joints

Distal intertarsal + tarsometatarsal joints

Hock OA etiology

Athletic use; genetics (juvenile spavin)

Hock OA clinical signs

Positive upper limb flexion; blocks to distal hock joints

Hock OA radiographs

Poor correlation with clinical lameness

Hock OA treatment

IA corticosteroids; squared toe shoeing; facilitated ankylosis; arthrodesis; laser; ethyl alcohol; drilling

Hock OA prognosis

Good; requires maintenance

Bog spavin definition

Tibiotarsal effusion

Bog spavin etiology

OCD; synovitis; poor conformation; hard work; rare OA; hemarthrosis; collateral ligament injury; septic arthritis

Bog spavin diagnosis

TT effusion; radiographs; ultrasound; arthroscopy

Bog spavin treatment

Drain + corticosteroids; arthroscopy

Bog spavin prognosis

Good; usually cosmetic if underlying issue addressed

Hock OCD most common site

Distal intermediate ridge of tibia (DIRT)

Hock OCD other sites

Trochlear ridge (lat > med); medial malleolus

Plantar ligament desmitis name

Curb

Curb etiology

Strain on plantar hock; sickle hocks; Standardbreds

Curb clinical signs

Characteristic swelling; mild-moderate lameness

Curb diagnosis

Blocks; ultrasound

Curb treatment

Rest; ligament injury protocol

Curb prognosis

Good; swelling persists

Capped hock definition

Calcaneal bursitis

Capped hock etiology

Repeated trauma; stall kicker

Capped hock clinical signs

Swelling; usually NOT lame

Capped hock treatment

Drain + corticosteroids; avoid infection

Capped hock prognosis

Excellent function; poor cosmesis

Septic calcaneal bursitis etiology

Wound over calcaneus; kick injury

Septic calcaneal bursitis clinical signs

VERY lame

Septic calcaneal bursitis diagnosis

Pressurize bursa; contrast radiographs; ultrasound

Septic calcaneal bursitis treatment

Tenoscopy flush; RLP; may need bursa opening + calcaneus resection

Septic calcaneal bursitis prognosis

Guarded

Thoroughpin definition

Tarsal sheath tenosynovitis

Thoroughpin etiology

Wear and tear; straight hocks

Thoroughpin clinical signs

Swelling; usually NOT lame

Thoroughpin treatment

+/- corticosteroids; often none; bandaging ineffective

Thoroughpin prognosis

Excellent athletic use; guarded cosmesis

Hock blemishes list

Thoroughpin; bone spavin; curb; capped hock; bog spavin

Reciprocal apparatus components

Gastrocnemius; SDF musculotendon unit; peroneus tertius

Ruptured peroneus tertius etiology

Trauma; foals; full limb casts

Ruptured peroneus tertius clinical signs

Can extend hock with flexed stifle; swelling; increased hock extension at trot

Ruptured peroneus tertius treatment

Arthroscopy for avulsions; stall rest

Ruptured peroneus tertius prognosis

Good; poor if stifle involved

SDF or gastrocnemius rupture etiology

Trauma

SDF/gastrocnemius rupture diagnosis

Clinical signs; ultrasound

SDF/gastrocnemius rupture treatment

Long-term splinting + rest

SDF/gastrocnemius rupture prognosis

Fair-poor; good if heals

Fibrotic myopathy definition

Fibrosis +/- ossification of semitendinosus

Fibrotic myopathy etiology

Trauma

Fibrotic myopathy clinical signs

Characteristic gait at walk; palpable hardening

Fibrotic myopathy treatment

Semitendinosus +/- semimembranosus tenotomy

Fibrotic myopathy prognosis

Fair; gait usually remains altered

Stringhalt

Neurologic; covered in neuro course

Stifle lameness gait

Jumps off lame leg; drags toe; worse with limb on outside of circle

Stifle lameness clinical signs

Effusion; femoropatellar pouch palpable; hind end atrophy

Stifle lameness diagnosis

Flexion tests; blocks; radiographs; ultrasound; arthroscopy; scintigraphy

Stifle OC breeds

WB, TB, QH

Stifle OC lesions

Medial femoral cysts; trochlear ridge OCD

Stifle OC diagnosis

Effusion; lameness when training starts; radiographs

Stifle OC treatment

Surgery at 1 year; debridement; cyst biologics/scaffolds; corticosteroids; screw

Stifle OC prognosis

Depends on severity; leads to OA

Stifle OA etiology

OC; trauma; athletic use

Stifle OA diagnosis

Blocks to stifle

Stifle OA treatment

IA corticosteroids

Stifle OA prognosis

Fair; high-motion joint

Upward fixation of patella definition

Medial patellar ligament catches on medial trochlear ridge

Upward fixation of patella etiology

Weak quadriceps; straight legs

Upward fixation of patella severe signs

Stifle locked in extension

Upward fixation of patella mild signs

Stifle "catches"

Upward fixation of patella treatment

Back horse up; strengthen quadriceps; hills; cavaletti

Upward fixation of patella surgical

Medial patellar ligament splitting/blistering; desmotomy (last resort)

Upward fixation of patella surgical risk

Distal patellar fragmentation