From palpation to nerve blocks: a look inside todays lameness exam in horsesDuring routine exams veterinarians look for changes including fluid in joints, sensitivity in soft tissues, and resistance to flexion. | Shelley PaulsonThe equine lameness examination mixes art with science. The detective work of pinpointing lameness in a horse takes experience, educated observation, and the strategic use of various diagnostic tools. In recent years this process has evolved with technological advances, but the goal remains the same: Find the source of horses pain. In this article weve reviewed pertinent research and consulted lameness specialists to give you an inside look at the equine lameness workup. Lets dive in.Which Horses Need Lameness Exams and When?Authors of the 2025 Equine Lameness Insights Report, which summarizes the feedback of more than 100 veterinarians in the global International Society of Equine Locomotor Pathology (ISELP) community, found 95% of respondents believe earlier detection could have prevented more serious lameness outcomes (tinyurl.com/yna843z7). Sleip, a gait analysis app company, conducted the survey. Most sport horse veterinarians recommend musculoskeletal evaluations twice a year to identify issues early.Take, for example, Jillian Mills, DMV, a board-certified specialist in equine sports medicine and rehabilitation (Dipl. ACVSMR) and owner of Presidio Equine Sports Medicine, based in Encinitas, California. Mills also holds certifications as an equine rehabilitation practitioner (CERP) and veterinary acupuncturist (CVA), is a member of ISELP, and an FEI-permitted treating veterinarian.Routine performance reviews allow your veterinarian to detect issues that may be subclinical before overt clinical signs of lameness appear, Mills explains, naming specific changes the doctor could be looking for during such an exam:Asymmetric fluid filling in joints or tendon sheaths that differs from findings on previous evaluationsPalpable thickening or sensitivity in a soft tissue structure, such as a tendon or ligament, that wasnt there beforeResistance to flexion of a specific jointLameness elicited when evaluating the horse dynamically following static flexion or pressure testing of a sensitive soft tissue region (in other words, the horse flexes positive)Any of these findings can be indicative of a subclinical (does not produce obvious clinical signs) issue that may warrant further evaluation and treatment, Mills says.First, Localize the ProblemWhat exactly do vets look for when they jog, flex, numb, radiograph, and ultrasound your horse? And why do they use such a systematic process, following a specific order?Tackling the first part, Elizabeth Davidson, DVM, Dipl. ACVS, ACVSMR-Equine, professor of sports medicine at the University of Pennsylvanias New Bolton Center, in Kennett Square, describes the lens through which she watches a horse move during a lameness exam. I look for an asymmetrical or otherwise uneven gait, she says. A lame horse adapts the limb and body movement away from the lameness, shifting his weight away from the pain.With forelimb lameness Davidson says the horse shifts his head and neck away from the lame leg, resulting in downward head and neck movement onto the sound limb, hence the popular phrase down on the sound. She says it can be more difficult to appreciate hind-limb lameness. When a horse is lame in a hind limb, there is upward movement of the pelvis when the lame hind limb bears weight (a pelvic hike), she explains.Decreased cranial (forward) or caudal (backward) phases of the stride, a short, choppy gait, and decreased air time (lack of lift or elevation) are other notable gait anomalies of lame horses, Davidson adds. While she prefers the walk and trot for lameness evaluation, she notes some lame horses exhibit asymmetrical movements during canter work. For example, some lame horses will start bunny hopping in the hind limbs and cross-cantering.Veterinarians use what they see and feel in this initial examination, combined with blocking (diagnostic analgesia) to try to localize lameness to a specific area. Then they conduct imaging to get a closer look.Referrals for Further DiagnosticsIf she does not find anything sinister on initial imaging in the field, Mills says she might inject a synovial (joint) structure with corticosteroids or biologics, both as a diagnostic and therapeutic option, before deciding to send the horse for advanced imaging.Realistically, not all underlying musculoskeletal injuries are evident on radiographs or ultrasound, Davidson explains. When preliminary diagnostic imaging in the field doesnt provide enough information to reach a conclusive diagnosis, she refers the horse to a hospital with advanced imaging.Davidson describes the best uses of common diagnostic imaging options available:Magnetic resonance imaging (MRI) provides an excellent way to identify soft tissue and bony injuries, including within the hoof capsule, she says. The modality also helps practitioners assess suspensory ligament injuries, especially in the case of subtle or equivocal ultrasound findings. It uses a powerful magnetic field and radiofrequency waves to produce detailed cross-sectional images of both soft tissue and bone.Davidson says she considers computed tomography (CT) excellent for bone pathology (disease or damage), especially for subchondral bone changes, which can be challenging to identify on radiographs. This approach uses radiographs taken from multiple angles to create thin 3D slices of the horses bone surfaces and joint margins, helping veterinarians detect subtle fractures, cysts, or areas of bone remodeling.Nuclear scintigraphy (bone scan) allows vets to evaluate the entirety of the skeleton, including the limbs, in addition to the skull, neck, back, and pelvis. It can often detect changes in bone earlier than radiographs. To perform a bone scan the practitioner injects a small amount of radioactive tracer into the bloodstream. Areas of increased bone metabolismfrom inflammation, remodeling, or injuryabsorb more of the tracer, which a gamma camera detects to create a heat-map-like image showing spots of concern.Finally, proton emission tomography (PET) is the newest imaging technology. Davidson likens it to a high-resolution 3D bone scan. Similar to scintigraphy, it involves administering radioactive tracers that accumulate in areas of increased metabolic activity.The Typical Lameness Exam SequenceIn most cases a complete standard equine lameness exam follows this general sequence: palpation, jogging or trotting under saddle, then flexion tests, regional nerve blocks, and, potentially, diagnostic imaging such as ultrasound or radiographs.Jillian Mills, DMV, Dipl. ACVSMR, CERP, CVA, owner of Presidio Equine Sports Medicine, based in Encinitas, California, begins her clinical evaluation by palpating the horses musculoskeletal structures. This includes both soft tissue and joint palpation, range-of-motion evaluation, thoracolumbar epaxial muscle reactivity, and flexion and extension through the back, followed by pelvic musculoskeletal sensitivity and symmetry.Unless it would be dangerous or a rider is unavailable, Mills says she prefers to evaluate soundness under saddle. Lameness is most appreciable at the trot because it is a symmetric gait, she explains. The majority of my under-saddle evaluation is performed at the trot, both in a frame and on a loose rein, (with the rider) on both the correct and incorrect posting diagonal. If I cannot appreciate a gait asymmetry under those conditions, or the presenting complaint is specific to a gait, transition, position, or conditional task, I will evaluate the horse accordingly.When performing flexion tests, Mills says if shes concerned about a specific limb based on the gait evaluation, she flexes that limb last. A very positive response, meaning a marked exacerbation in lameness, can affect your assessment of the other limbs if that lameness persists, she explains.Depending on the reason for the exam, history of past treatments, and clinical exam findings, your veterinarian might perform diagnostic nerve blocks (regional anesthesia), she continues, which temporarily numb a suspected area of interest to see if the lameness improves with lack of sensation. Nerve blocks must be performed distally to proximally (progressively moving up the leg) because they numb not only the injected region but also the structures below it.If this is a performance review and we have a serviceably sound horse that is mildly reactive to flexion testing, it may indicate subclinical synovitis (inflammation of the joint capsule), Mills says. Treating it with an intra-articular treatment is a diagnostic therapeutic in itself.However, with a clear lameness, regional nerve blocks and/or intrasynovial analgesia (joint blocks) can help localize the region causing pain, Mills says. Whether I choose to start with nerve blocks or a specific synovial structure depends on my exam findings, as well as the horses temperament, she explains. For example, I may start with an intra-articular stifle block in a less compliant horse with a hind-limb lameness if that horse has an effusive (fluid-filled) stifle and is reactive to upper-limb flexion.After she localizes the suspected lameness source, Mills often turns to radiography (X rays) or ultrasound at the farm. These imaging modalities are largely structural, meaning they primarily evaluate the horses anatomy, she says. Doppler ultrasound enables us to evaluate the vascularization of soft tissue structures, such as tendons or ligaments, which often lack blood flow outside of inflammation or injury.However, she cautions that some older horses with previous injuries can have residual blood flow to affected structures even when they are no longer the source of lameness. We often find imaging abnormalities, but you need to be able to correlate those findings with your clinical exam, she says.Behavior During Lameness ExamsBeyond pinpointing the source of pain, practitioners closely observe how lame horses behave while jogging, longeing, and/or riding. In the veterinary literature, an ever-expanding body of evidence links various gait abnormalities exhibited during riding or lameness examinations to underlying musculoskeletal pain, Davidson says, citing the Ridden Horse Pain Ethogram (RHPE), developed by Sue Dyson, VetMB, PhD, which lists 24 behaviors frequently exhibited by lame horses (Dyson, 2022).Take-Home MessageAs with most aspects of horse care, collaboration between owners and veterinarians over time makes a world of difference in the management of equine athletes musculoskeletal health. Regular routine lameness exams remain a valuable opportunity to proactively detect and address early signs of wear and tearbefore they snowball into bigger performance and soundness issues for your horse.ReferenceDyson S. The ridden horse pain ethogram. Equine Vet Educ. 2022;34(7):372380.This article is from the Spring 2026 issue ofThe Horse: Your Guide to Equine Health Care. We at The Horse work to provide you with the latest and most reliable news and information on equine health, care, management, and welfare through our magazine and TheHorse.com. Your subscription helps The Horse continue to offer this vital resource to horse owners of all breeds, disciplines, and experience levels. To access current issues included in your subscription, please sign in to theAppleorGoogleapps ORclick herefor the desktop version.