Normal Gait: Consists of a swing phase and a stance phase (starting with lateral hoof impact and ending when the foot is lifted).
Influencing Factors: Locomotion is affected by individual traits (breed, age, conformation) and environmental factors (surface type, moisture, obstacles).
Detection Philosophy: Traditionally based on subjective visual identification of movement deviations caused by pain.
Clinical Indicators of Lameness
Locomotion Changes: Decreased speed and stride length; increased abduction or asymmetry.
Postural Shifts:Arched back, cow-hocked stance, hind-limb protraction/retraction, or knuckling of the fetlock.
Weight Distribution: Shifting weight between limbs or uneven weight bearing.
Behavioral Alterations: Changes in lying, standing, feeding, and socializing patterns.
Locomotion Scoring Systems
Standardization: Over 28 systems worldwide, typically using 3- or 5-point scales.
Purpose: Used as a herd health screening tool for early identification and welfare quality assurance.
Key Indicators: Evaluates head bob, back arch, tracking up, stride speed, and joint stiffness.
Challenges in Detection
Stoic Nature: Cows often mask pain, leading to low diagnostic performance for visual scoring.
Temporal Lag: There is often a delay between the onset of pain and when a lesion becomes visible on the sole.
Subjectivity: Requires ongoing training; producers often underestimate lameness, missing 60%–80% of lame cows.
Automated Technologies
Kinematic Methods: Analyze body motion over time using image processing or accelerometers.
Kinetic Methods: Analyze the force applied to the body via pressure plates or weighing platforms.
Indirect Methods: Utilize tools like infrared thermography.
The 4-Step Lameness Examination
1. Locomotion Evaluation: Initial assessment to determine if pain is in the front, hind, or upper limb.
2. Physical Limb Examination: Includes proper restraint, thorough inspection of the interdigital space, functional hoof trimming, and the use of hoof testers to elicit pain responses.
3. Ancillary Diagnostics:
Nerve Blocks: Digital or intravenous regional anesthesia (lidocaine) to localize pain.
Imaging: Radiography (for fractures/sepsis) and Ultrasonography (for soft tissue/tendon injuries).
Advanced: Arthrocentesis and synovial fluid analysis for suspected joint disease.
4. Differential Diagnosis: Consolidating findings to create a specific treatment plan.