Lameness Flashcards
You suspect a horse is lame.
What are the 2 area’s of its body that you should watch closely to DX which area is causing the problem?
- Poll
- Hip
(front end vs. hind end)
What happens to the horse’s head
when a lame horse trots?
they raise their head when the lame front foot strikes the ground.
List the 3 clinical reasons for lameness.
- Pain (majority)
- Mechanical
- Neurological defect
In what age group does OCD present?
Young horses that just started training
In what age group does OA more commonly present?
Older horses
What are 2-3 year old Throughbred racehorses are prone to?
Stress Fractures
What are Standardbred racehorses prone to?
Carpal lameness
What are 3 day Event horses prone to?
Back pain
What are Warmblood dressage horses prone to?
- Distal tarsal joint arthritis
- Proximal suspensory desmitis
What are Polo ponies prone to?
SDFT tendonitis
What one question you should be sure to ask when taking the HX of a lame horse?
When was the horse last shod?
Which angular limb deformity is this?
Varus
“Bow legged”
Which angular limb deformity is this?
Valgus
“knock kneed”
What 2 things do horses with broken back (hoof-pastern axis) often get?
- Chronic heel soreness
- Proximal suspensory desmistis
Severe carpal valgus will cause what 2 problems for horses?
- Carpal lameness
- Medial splints
List 3 things that this horse will be prone to
due to its poor hind end conformation
- Upward fixation of the Patella
- Suspensory desmitits
- OA in the distal hock joints
(“straight through the hocks”)
What will this horse be prone to due to its poor confirmation?
- OA of the distal hock joints
- Desmitis of the long plantar ligament (curb)
You are performing a PE on a lame horse.
What is one area of the body that is every important, but often overlooked?
The mouth
Can be causing the horse pain & discomfort, which will throw off their natural balance
You find these while performing a PE on your client’s horse.
What should you tell the owner?
- They are wind puffs → thickening of the tendon sheath
- Non-pathogenic
- Assocaited with heavy “work”
- No need to worry about them
If a horse comes to you 3-legged lame, what are your top 3 concerns?
- FX
- Subsolar abscess
- Septic synovial structure
Where does lameness almost always originate?
In the area distal to the carpus or hock
Which type of lamess gait is seen most frequently in lameness exams?
Supporting limb lamess
(lameness during weight bearing)
Swinging limb lamenesss is often due to a _______________.
Mechanical deficit
(i.e. fibrotic myopathy, stringhalt)
What grade would you give a horse if the lameness is consistently observable at a trot, under all circumstances?
Grade 3
What grade do you give a horse with lameness that is obvious & has marked nodding, hitching &/o shortened stride?
Grade 4
What grade do you give a horse that is unable/refuses to move?
Grade 5
How do you evaluate the forelimb gait of a horse?
- Look for “head nod”
- Listen to feet strike the ground
- sound forelimb will be louder
- Look at phase of stride/limb flight
What is the cause of 80-90% of lameness in horses?
- Palmar heel pain/Navicular syndrome
- Solar bruising/abscess
- DJD
“in the foot”
How will a bilaterally lame horse appear to move?
They will have a short, shuffling gait
How do you best observed hind end lameness?
When the horse is being trotted away from you
What are signs of lameness in the hind end?
- increased displacement of coxae
- decreased sound from shoe contact
- Reduced cranial/caudal phase of stride
What will happen with the horse’s head and neck
if it suffers from hind end lameness?
The head and neck will shift forward and nod down at the same time
(Horse is trying to shift its weight cranially away from the lame limb)
Why are Provocative Tests done on lame horses?
- to “tease-out” inconsistent lameness
- to exacerbate a mild lameness
- to help isolate the location of lameness
What is the primary disadvantage of Flexion Tests?
Unable to distinguish btwn an intraosseous and a soft tissue injury
(just helps isolate the area)
What is the problem with performing Flexion Tests in the hind limbs?
Reciprocal apparatus does not allow for the stifle and hock to be flexed individually.
How is DX analgesia performed in lameness evaluations?
- Perineural anesthesia→ migrates & infiltrates
- Intrasynovial anesthesia
- Typically work distal to proximal
List the 3 commonly used LA in Equine Medicine.
- Lidocaine HCL
- rapid onset, short action
- Mepivicaine HCL
- rapid onset, mid-duration
- Bupivicane HCL
- slower onset, longer duration
What are the limitations of nerve blocks?
- Best done W/O sedation → dangerous to the vet
- Can’t use if cellulitis or dermatitis is present
- Interferes w/ other tests
- nuclear scintigraphy (have to wait 2 wks)
If you are performing a nerve block on a synovial structure,
what precautions are necessary?
- Aspetic technique
- New bottle of LA
- Sterile gloves
What are contraindications for performing nerve blocks?
- If you suspect a FX
- Horse is being ridden or lunged
What is the most commonly performed regional nerve block of the forelimb?
What areas does it block?
- Palmar digital nerve block
- anesthetizes the entire foot, including the distal interphalangeal (coffin) joint.
What nerve blocks are done on the thoracic limbs?
- Palmar digital
- Abxial sesmoid
- Low 4 Point
- High 4 Point → Lateral palmer & suspensory origin
- Median & Ulnar → Musculocutaneous
List the nerve blocks used in the Pelvic limbs
- Plantar digital
- Abaxial sesamoid
- Low Plantar (6 point)
- High Plantar (6 point)
- Tibial & Peroneal
What is desensitized by the PD Block?
The palmar 1/3 & all of the sole
What region is NOT desensitized by a PD block?
Doroproximal
- Coronet
- dorsal laminae
- DIP
What does improved lameness after a Palmar/Plantar Digital Nerve block indicate?
The pain is coming from th foot
What does the Abaxial Sesamoid block desensitize?
desensitizes the entire foot, the pastern joint, the short pastern bone and their associated soft tissues.
What nerves are blocked in the Low 4 Point block?
- Palmar Metacarpal n.
- Palmar n.
What areas are desensitized by the Low 4 Point block?
- Navicular structures
- Soft tissue structures of pastern and foot
- Sole, Laminae
- Three phalanges
- Coffin and Pastern and Fetlock joint
- Distal Digital tendon Sheath
What nerves are blocked in the Low 4 Point on the hindlimb?
- Palmar Metacarpal n.
- Palmar n.
- Dorsal Metatarsal n.
- Digital Extensor tendons
What nerves are blocked in the High 4 Point block?
What area of the leg gets anesthetized?
- Palmar Metacarpal n.
- Palmar n.
- Anesthetizes palmar metacarpus from distal carpus + Carpo-metacarpal joint + carpal sheath
What is accomplished by the Tibial Peroneal Block?
Anesthetizes deep pain from the distal tibia down
What are the disadvantages of the Tibial & Peroneal block?
- Difficult test to “read”→ only 50-80% effective
- Peroneal: toe drag (extensors blocked)
- Inconsistent skin sensation
- Takes up to 1 hr. to reach full effect
- Not good to rely on for distal limb lameness
What parts of the body is Intra-synovial Anesthesia used?
- Articular
- Tendon sheaths
- Bursae
What is digital radiography NOT good for in horses?
Cartilage damage
What is an Enthesiophyte?
Bone formation at a site of soft tissue attachment
What is U/S best used for in Equines?
- Soft tissue
- Ligaments, cartilage, tendons, menisci
- Helpful at bony sites
- Abscess vs. Hematoma
What does increased uptake of Tc99 during Nuclear Scintigraphy indicate?
- Bony remodeling
- Increased blood supply → acute inflammation
What is Nuclear Scintigraphy NOT good for?
Chronic issues such as arthritis
What is MRI useful for?
- Extremely sensitive for bone & soft tissue
- Able to image areas difficult to image w/ other madalities (hoof capsule, skull)
