Proximal suspensory desmitis (PSD)

Veterinary advice should be sought before applying any treatment or vaccine.

Proximal Suspensory Desmitis (PSD)

Proximal suspensory desmitis (PSD) is the inflammation of the proximal aspect of the suspensory ligament. It is a common injury in performance horses, and can occur in the forelimbs and/or hindlimbs.

PSD of the Hindlimbs

Horses with excessively straight hocks or why hyper extended metatarsophalangeal joints are more at risk of PSD in the hindlimbs. Most affected horses are performance horses between 4 to 10 years of age. Thoroughbreds and Thoroughbred cross breeds are more commonly affected by this injury.

PSD of the hindlimb causes acute or chronic hindlimb lameness in horses. Lameness is often most obvious when the horse is being exercised. When the horse is observed in motion, affected horses usually show decreased arc of foot flight with a shortened cranial phase.


Insidious or sudden onset of persistent mild to moderate lameness
Poor performance
Decreased foot flight
Loss of hind-limb impulsion
Unwillingness to move forward freely
Refusing jumps
Lack of power when jumping
Difficulties performing dressage movements


  • History
  • Clinical signs
  • Lameness exam
  • Ultrasonography
  • Radiographs
  • Magnetic resonance imaging (MRI)
  • Histology



Stall rest and rehabilitation programUsually requires extended period of stall rest followed by gradual return to exercise. Rehab programs are customized for each individual horse depending on the location and severity of the injury and use and training level of the horse.
Shockwave therapy
Radial pressure-wave therapy
Regenerative medical therapiesStem cell therapy



Acute injuries generally have a favorable outcome, with 90% of horses returning to full athletic function with conservative management.

Scientific Research

General Overviews

Clinical Trials

Risk Factors

  • Poor Conformation - Horses with excessively straight hocks or hyperextended metatarsophalangeal joints.
  • Breed - Thoroughbred and thoroughbred crosses are more at risk of developing this injury.