Lecture 30 4/8/25 Flashcards
What is lameness?
-abnormality of normal gait
-manifestation of signs of inflammation/pain, neurological dz, or mechanical defect
-evident as asymmetry of movement
What does diagnosing lameness entail?
-recognizing the lameness
-determine the involved limb(s)
-localize lameness to a particular structure
What are the causes of lameness?
-pain (most commonly)
-neurologic dz
-mechanical
What are the goals of the lameness exam?
-make a diagnosis
-identify and localize lameness
-provide treatment options and prognosis
What are the steps to a lameness exams?
-history
-visual exam at rest
-in-motion exam
-manipulation
-localization
-diagnostics
What are the conditions needed for a lameness exam?
-adequate time
-good weather
-quiet area
-horse off medications
-owner/agent available
-horse must actually be lame
What equipment is used in the lameness exam?
-hoof testers
-hoof knife
-longe line
What is important to ask during the history portion of the exam?
-signalment and use of the horse
-what the owner/trainer has noticed
-duration and severity of signs
-any treatments and response to them
-current medications
-last shodding
What is assessed during the at rest visual exam?
-conformation
-stance
-swelling
-palpation to check digital pulses, tendons, joints, etc.
What are the key components to the in-motion exam?
-have horse on a hard, flat surface
-evaluate all gaits
Which gaits are evaluated in an in-motion exam?
-walk
-trot
-pace
-canter/lope
What are the characteristics of gaits in a sound horse?
-equal anterior and posterior phases of stride
-normal foot flight arc
What is important to assess during a walk?
-foot fall pattern; normal is heel to toe, balanced medial/lateral
-swinging phase; want no interference
-hoof strike sounds; should be equal
What are the characteristics of trot assessment?
-lameness is most obvious at a trot
-one pair of limbs is always on the ground
-use a loose lead and do a slow trot so the horse can move its head
-observe from front/hind and side
What are the characteristics of forelimb lameness?
-head bob occurs on affected limb in grades 2+
-shifting of shoulders occurs in grades 2 and below
-shortened posterior phase suggests soft tissue problems
What are the characteristics of hindlimb lameness?
-gluteal rises and gluteal drops occur in grades 3+
-head bob occurs on contralateral forelimb in grades 3+
-shortened posterior phase suggests soft tissue problems
-side with greatest vertical excursion is lame
What are the characteristics of the down on sound rule for trotting?
-if animal is lame in the front, the head will go down when the sound limb contacts the ground
-if animal is lame in the hind, the head will go down when the lame limb contacts the ground
What are the characteristics of asymmetrical pelvic movements?
-assess total vertical displacement of tuber coxae during trotting
-side which shoes greatest displacement is lame limb
What is the rule of sides?
-if head goes down when left forelimb hits the ground, the lameness is on the right side
-if head goes down when the right forelimb hits the ground, the lameness is on the left side
What are the lameness grades?
0: not perceptible under any circumstances
1: difficult to observe and not consistently apparent under any circumstances
2: difficult to observe when walking or trotting; consistently apparent under certain circumstances
3: consistently observable at a trot under all circumstances
4: obvious at a walk
5: minimal weight bearing in motion and/or at rest or a complete inability to move
What are the classifications of lameness from visual assessment?
-supporting limb lameness
-swinging leg lameness
-mixed lameness
What are the classifications of lameness from the inertial sensors?
-impact
-mid-stance
-pushoff
What are the characteristics of hoof testers?
-applied over entire hoof and then repeated on sensitive spots
-want to trot after applying pressure to sensitive spots for 30 to 60 seconds
-good time to evaluate sole consistency, shoe/hoof wear, and hoof conformation
What are the characteristics of longe line?
-work horse in 10 to 20 meter circle at all gaits
-exaggerates lameness on limb to the inside of the circle OR lameness on the outer limbs if it is on the medial side of the limbs
-lameness is grade 2 or lower if ONLY observed on longe
less reliable for hind limbs
What are the goals of flexion tests?
-isolate lameness via manipulation
-standardize flexions to have similar results among all patients
What are the possible results of flexion tests?
-no change
-slight positive/somewhat exacerbated lameness
-moderate positive/exacerbated lameness for part of gait test
-severe positive/exacerbated lameness for all of gait test and time after
What is the sequence and time of flexion tests?
-distal forelimb: 30 sec.
-proximal forelimb: 60 sec.
-distal rear limb: 30 sec.
-full rear limb: 60 sec.
-stifle and hip: 60 sec.
What is the technique for forelimb fetlock flexion?
-try to keep proximal limb as straight as possible
-hold for 30 sec.
What is the technique for proximal forelimb flexion?
-flex elbow and shoulder
-try to keep fetlock straight
-hold 60 sec.
Why is rear fetlock flexion difficult to do on its own?
reciprocal apparatus will make it difficult to keep the stifle straight
What is the technique for proximal rear limb flexion?
-flex as much as horse permits
-grasp hoof to keep from putting pressure elsewhere
-hold 60 sec.
Which other manipulations can be done besides hoof testers and flexion?
-suspensory ligament and branches
-SDF/DDF
-sesamoid bones
-pressure on joint and tendon sheath effusions
-riding/driving
How is lameness localized other than manipulations?
regional and articular anesthesia
Which diagnostic tests are used to diagnose lameness?
-rads
-ultrasound
-nuclear scintigraphy
-CT
-MRI (soft tissue surgery)
-thermography
What are the characteristics of rads?
-require good diagnostic technique and adequate interpretation
-typically need AP, lateral, and oblique views (4 total)
What are the characteristics of ultrasound?
-used for serial monitoring of a variety of lesions
-underestimates degree of damage
-overestimates degree of healing
What are the characteristics of nuclear scintigraphy?
-detects bone metabolism using technetium 99 phosphate
-three phases include circulatory, soft tissue, and bone
What are the characteristics of CT?
-excellent for bone lesions
-can do 3D reconstructs
-can do contrast to delineate soft tissue
What are the characteristics of thermography?
-visualization of skin surface temps to within 0.2 deg. C
-useful adjunct for eval. of back pain, saddle fit, and hoof balance
What are the benefits of equinosis Q?
-easily determine lameness when not observable with naked eye
-quantify degree of lameness for accurate and and objective evaluations
-determine impact vs. push-off lameness
-determine primary and compensatory causes of lameness
-can identify improvements in the lameness over time
Where are the sensors placed for equinosis Q?
-body mounted inertial sensors at the poll, right front pastern, and between the tuber sacrale
-accelerometers on head and pelvis
-gyroscope on right forelimb
How many trot strides must a horse take for equinosis Q to work?
25 (not including slow downs and turns)
How can equinosis Q be used with other lameness tests?
-combined with diagnostic analgesia to determine improvement after blocks
-combined with flexion to compare pre- and post-flexion
