The Lameness Workup: A Clinical Guide to Gait Assessment, Diagnostic Localization, and Case Management in the Horse

The Lameness Workup walks through the complete equine lameness exam in the order it actually happens in the clinic aisle. It opens with the functional anatomy of the distal limb, fetlock, carpus, tarsus, stifle, shoulder, and axial skeleton — the vocabulary every later chapter depends on — then moves through the AAEP grading scale, structured history and conformation assessment, and the full observation-palpation-manipulation sequence. From there it builds outward into gait analysis, covering the trot-up, lungeing, and flexion-test protocol alongside sensor-based objective asymmetry indices, and then into diagnostic analgesia:

1. Functional Anatomy of the Equine Musculoskeletal System — distal limb bones, tendons, ligaments, and joints; carpus, tarsus, stifle, shoulder, and hip; axial skeleton basics; how structure predicts common injury sites
2. Principles of Lameness: Terminology and the AAEP Grading Scale — lameness vs. gait abnormality, the full 0–5 grading scale, weight-bearing/non-weight-bearing/mixed patterns, mechanical vs. supporting-limb vs. swinging-limb lameness, communicating grades to owners
3. History, Signalment, and Conformation Assessment — structured history-taking, age/breed/discipline-driven differentials, conformation's relationship to injury risk, static assessment technique
4. The Systematic Exam: Observation, Palpation, and Manipulation — standing exam at rest, distal-to-proximal palpation sequence, digital pulses and heat, effusion grading, flexion test technique and interpretation caveats
5. Visual Gait Assessment: Trot-Up, Circling, and Flexion Tests — straight-line and lungeing protocol, head-nod and pelvic-hike recognition, forelimb vs. hindlimb signs, ridden evaluation basics
6. Objective Gait Analysis: Sensors and Asymmetry Indices — inertial sensor systems, asymmetry plots and threshold values, worked calculation examples, integrating objective data with visual assessment
7. Diagnostic Analgesia I: Distal Limb Nerve Blocks — palmar/plantar digital, abaxial sesamoid, low four-point, high four-point, and low six-point blocks, each with technique, structures desensitized, and interpretation
8. Diagnostic Analgesia II: Proximal Limb and Intra-Articular Blocks — proximal perineural blocks, intra-articular technique for major joints, sterility protocol, false positive/negative and diffusion caveats
9. Diagnostic Imaging I: Radiography and Interpretation — standard views by region, positioning technique, systematic reading approach, common findings as labeled schematics
10. Diagnostic Imaging II: Ultrasound, Scintigraphy, CT, and MRI — tendon/ligament ultrasound technique, cross-sectional anatomy correlation, modality selection guidance
11. Conditions of the Foot and Distal Phalanx — navicular and palmar foot pain, laminitis, hoof abscess, sole bruising, white line disease
12. Conditions of the Fetlock and Pastern — osteoarthritis, osselets, sesamoiditis, sesamoid ligament injury, high and low ringbone
13. Conditions of the Carpus, Tarsus, and Proximal Limb — carpal chip fractures, bone spavin, curb, stifle and shoulder-region conditions
14. Conditions of the Axial Skeleton: Back, Neck, and Pelvis — kissing spines, sacroiliac pain, cervical facet disease, primary vs. compensatory back pain, saddle fit
15. Musculoskeletal Emergencies and Acute Severe Lameness — fracture stabilization, laminitis crisis management, septic joint/tendon sheath recognition, referral triage
16. Therapeutic Options, Case Management, and Return-to-Work — controlled exercise protocols, rehabilitation modalities, prognosis communication, structured return-to-work progression