Musculoskeletal 1-4 Flashcards
Which claws are commonly found lame on the forelimb and hindlimb?
Forelimb=medial claw (WB claw)
Hindlimb=lateral claw (WB claw)
What is the corium response?
When there is increased weight bearing there will be increased rate of horn production
If there is an imbalance in the weight bearing on the claws in cattle, what can result from that?
Increased risk for trauma to the corium and ulcer formation
What are the different behavior criteria used to assess lameness in cattle?
Head carriage (no bob) Flat vs. arched back Tracking up (hind limbs meet almost perfectly with forelimbs) Joint flexion (symmetrical) Gait symmetry Weight bearing
Briefly describe grades 1-5 of cattle lameness scoring
1: smooth, fluid movement
2: imperfect locomotion but moves freely still (shortened gait)
3: compromised ability to move freely
4: ability to move freely is diminished
5: encouragement needed for cow to move
What is the hoof horn initially created by?
The dermis –> in the end the hoof is dead dermis
Which part of the claw is the hardest and softest in cattle?
Tubular horn=hardest
Abaxial heel=softest
Where is foot rot seen in cattle vs. small ruminants?
Cattle: interdigital dermis
SR: abaxial claw
What is the condition where there has been damage to the interdigital dermis by bacterial invasion?
Interdigital phlegmon/foot rot
What is the bacteria that invades the interdigital dermis/abaxial claw in SR/cattle to lead to foot rot?
Cattle: Fusobacterium necrophorum
SR: Dichelobacter nodosus
What is the pathogenesis of foot rot?
Damage to dermis creating anaerobic environment –> opportunistic invasion of bacteria –> more tissue destruction (proteases/leukotoxin formation) –> clot formation & local ischemia
How is the opportunistic bacteria involved with foot rot not destroyed by phagocytosis?
The leukotoxins protect the bacteria
What is the treatment for foot rot?
Debridement (creates aerobic environment) Systemic Ab (Ceftiofur or oxytetracycline)
What bacteria is involved with digital dermatitis?
Treponema spp.
What is digital dermatitis predisposed by?
Confinement, excess manure, increased standing, overcrowding
What is the tx for digital dermatitis?
Debridement
Topical Ab
Foot baths (copper sulfate)
What is foot rot in small ruminants best treated with?
Gamithromycin
Which antibiotic has the shortest meat withdrawl time?
Ceftiofur
What is the condition where there is bacterial degradation of the heel horn?
Heel horn erosion
Where does claw horn disruption begin?
Inside the hoof at the corium
mechanical overload on abaxial claw of hindlimbs
How many hours a day should a cow be laying down?
10-12 hours
In claw horn disruption the corium is pinched between P3 and the sole leading to what?
Hemorrhage and ulcer
Where is the damage in a sole ulcer?
Dermal/epidermal damage- interruption of horn production
Which claw will you apply a block to?
Sound claw
What is the tx for sole ulcers in cattle?
The initial problem that led to the ulcer is no longer present- you need to dish out the sole and redistribute the weight leaving the corium flush with the sole
How can sole ulcers be prevented?
Environmental management
What is the condition where there is inflammation and ischemia of the laminar corium leading to shearing and compression forces of P3?
White line disease
T/F: Cattle typically are found with subclinical laminitis
TRUE
Cattle- hind end; Horses- front limbs
What is the characteristic stance of a cow with laminitis?
Relaxation of suspensory apparatus –> toe tips up
Which ligaments are affected in laminitis?
cruciate ligaments are affected at attachment site
What process disrupts horn production in laminitis?
Aseptic inflammation of corium
What does acute grain overload cause?
Increase in IL-1 in hoof laminae
What is MMP (matrix mettaloproteinase) activated by in laminitis?
Cytokines, ROS, NO (inflammation)
What is the tx for chronic laminitis in cattle?
hoof trimming and diet management
What are some preventative methods for laminitis?
Stalls Flooring Diet Hygiene Foot baths Trimming
What are the three common areas luxations are seen in cattle?
Hip
Stifle
Proximal interphalangeal joint
T/F: You can feel a sacroiliac luxation on transrectal palpation
TRUE
What is physitis caused by?
Growing too quickly
What is sciatic nerve paralysis caused by?
Dystocia and pulling too hard leading to nerve damage
What is the classic stance of a sciatic nerve paralysis?
Dropped hock and partially/fully knuckled over at the fetlock
Where are tibial fractures commonly seen and caused by in cattle?
Mid-shaft
Traumatic cause
What are the tx options for tibial fractures?
Walker splint
Thomas splint-cast
What muscle is ruptured if the hind limb extends back beyond normal limits?
Peroneus tertius m.
What muscle is ruptured if the cow is weight bearing on the hock?
Gastrocnemius m.
What is noticed in a cows gait with a stifle injury?
Short stride, limited flexion, walk on toes w/ heels elevated, leg held in abduction, little weight bearing
Which collateral ligament is more commonly torn?
Medial collateral ligament
What is the difference in tx of fractures that are distal from the body vs. proximal to the body?
Distal MC: half-limb cast; Proximal MC: full limb cast
Distal radial/ulnar: full limb; Proximal: transfixation, bone plate
Why should you avoid draining a hygroma?
Abscess formation- will regress on its own
What does radial n. paralysis look like?
Dropped elbow (can still support weight just cannot place on it’s own)
