Page 336 - The Veterinary Care of the Horse

• low intensity laser therapy

• ultrasound therapy
VetBooks.ir • shock wave therapy

•
ligament splitting may be performed if there is a core lesion.

Healing is monitored by regular ultrasound examinations. As with suspensory body injuries,
the lesions may not return to a normal appearance on ultrasound scans so they are not always

helpful in deciding when to resume full work.

PROGNOSIS

The prognosis depends on the severity of the injury and whether it is associated with a

fracture or inflammation of the sesamoid bones. Horses suffering from severe ligament
damage are prone to re-injury of the suspensory ligament.

ANNULAR LIGAMENT SYNDROME

Anatomy

The annular ligament of the fetlock joint lies at the back of the fetlock between the two
sesamoid bones. (See Figures 7.1b and 7.5.) It forms part of a canal through which the
superficial and deep digital flexor tendons pass on the way to their attachments on the middle

phalanx and the distal phalanx (pedal bone). This canal is lined by the synovial membrane of
the digital flexor tendon sheath. Inflammation or desmitis of the annular ligament has several

causes and is referred to as ‘annular ligament syndrome’.

Causes

• Direct trauma, e.g. an overreach or cut.

• Indirect trauma, e.g. repeated overextension of the fetlock whilst exercising.

• Swelling of the superficial or deep digital flexor tendons close to the fetlock as a result of
injury can exert pressure and cause inflammation of the annular ligament.

• Inflammation or infection of the digital flexor tendon sheath (DFTS) can cause pressure

on the ligament.

Whatever the cause, the inflamed ligament becomes thickened which reduces the space