What Do We Know About Rehab Modalities in Horses?
Following injuries, which are frequent events in athletic horses, owners and trainers commonly seek one or more alternative therapies to facilitate rehabilitation. While many people extol the virtues of rehabilitation modalities, claiming they expedite the healing process or even cure the horse, those testimonials rarely rely on the science surrounding the techniques.

Given the popularity of rehabilitation modalities in modern equine practice, Katherine Ellis, DVM, a third-year equine sports medicine and rehabilitation resident at Colorado State University, recently reviewed the available indications, proposed mechanism of actions, and regulation of rehabilitation modalities during the 2019 Annual Convention of the American Association of Equine Practitioners (AAEP), held Dec. 7-11 in Denver.

The complete article, “Review of the current literature of common rehabilitation modalities,” provides far more details that can be included in this skeleton synopsis, but the following table offers a bird’s-eye view of Ellis’ presentation.

“When considering the following modalities, be certain to review the regulations of the governing body appropriate for your event,” she said. “The FEI, USEF, and other organizations like AQHA often have regulations regarding the accepted use of these modalities during competition.”

Modality Proposed Mechanism of Action Evidence for use in Equine Medicine Additional notes
Laser Therapy (LT)
  • Modulating pain
  • Reducing neuropathic pain
  • Reducing inflammation
  • One study involving 150 sport horses showed a beneficial effect of LT on tendinopathy/desmopathy, including the superficial and deep digital flexor tendons and suspensory ligament
  • Another study found 10/14 horses with back pain showed clinical improvement after lasering acupuncture points
  • LT may also enhance stem cell applications (experimental)
  • Class 4 lasers are prohibited at FEI events
  • Clipping hair and pigmentation of skin may alter penetration of laser
Transcutaneous electrical nerve stimulation (TENS)
  • Primarily functions through pain control by blocking pain signals to the spinal cord from C-fibers and releasing endorphins
  • No clinical studies supporting its use in equine medicine.
  • Recommended in humans with chronic musculoskeletal pain together with traditional medications
  • Clip the hair and use ultrasound gel to maximize contact between application pads and skin
  • At FEI events, must be applied by a veterinarian
Therapeutic ultrasound (TU)
  • Thermal use of TU reduces pain and muscle spasms and increases tissue elasticity
  • Nonthermal therapeutic effects include stimulating tissue repair, collagen synthesis, and bone healing
  • One study found that TU could heat the SDFT and DDFT but had questionable effects within the epaxial musculature
  • In humans, TU reduces pain due to osteoarthritis and facilitates fracture repair
  • Can be performed by owner/trainer with written permission from veterinarian for FEI events
  • If stretching the horse, do so immediately, before the tissues cool
Radiofrequency diathermy (DF)
  • Warms tissues, particularly in cases of joint and muscle effusion
  • Has not been objectively evaluated in horses
  • Human studies shows that RD improves pain, range of motion, and performance of day-to-day activities in cases of frozen shoulder, decreases pain and improves muscle performance in osteoarthritis
  • Treating veterinarian must by obtained by FEI officials
  • Contraindicated in patients with metal implants
Elastic therapeutic taping
  • Thought to reduce pain, enhance proprioception (awareness of the body’s position), and improve muscle activation
  • Limited evidence in any species supports the use of this modality
  • Only permitted if used within stable area at FEI events and if the horse is unmounted in stable area at USEF events
Pulsed electromagnetic field therapy (PEMF)
  • Primarily used to aid bone healing, regulates bony elements and maintains bone mass
  • Thought to reduce pain and inflammation by stimulating nitric oxide
  • Limited evidence in horses
  • One canine study found significantly faster recovery of load bearing following tibial osteotomy
  • Approved by the FDA in humans with long bone fracture nonunions and following lumbar/cervical spine fusion surgery
  • Use is not restricted in competition
  • Caution should be used for tendon healing as it might delay the process
Underwater treadmill (UWT)
  • Use for rehabilitation of both acute and chronic injuries. Buoyancy allows partial weight bearing to alleviate stress and pain on lower extremity joints; improves gait if the horse is deficient in muscle strength, postural control, or motor coordination; and improves balance
  • Warm water can improve muscle comfort during training, and cold water can have cryotherapeutic effects
  • In horses, UWT improves muscle strength, postural stability, motor control, and joint range of motion
  • No restrictions on use
  • Water height must be adjusted to each patient’s condition and therapeutic goals
  • Not all patients are ideal candidates for UWT
Whole-body vibration therapy (WBV)
  • Presumably increases muscle strength, postural stability, and power by stimulating motor neurons, skin receptors, muscle cells, and joint mechanoreceptors
  • The one study in horses using WBV shows maintenance of bone density in stalled horses
  • WBV increases the mass of the multifidus (back) muscle and can deter back osteoarthritis
  • More research is needed
Neuromuscular electrical stimulation (NMES)
  • Restores normal muscle function and strength following muscle atrophy and nerve injury
  • One study supported the use of NMES for horses with injury to the recurrent laryngeal nerve and cricoarytenoid muscle that innervates the larynx (think roarers)
  • Must be performed by a veterinarian for FEI events
  • The hair may need to be clipped and should definitely be cleaned of dirt/debris before applying coupling gel