Page 164 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

Musculoskeletal system: 1.4 The forelimb 139

VetBooks.ir 1.251 1.252

Figs. 1.251, 1.252
Dorsopalmar (1.251)
and flexed lateromedial
(1.252) radiographs
of a fetlock joint with
a well-demarcated
osseous cyst-like lesion
just medial to the
sagittal ridge.

Differential diagnosis poorly attached cartilage/subchondral bone. Mild
Fetlock joint trauma; PSB fracture (e.g. apical/abax- flattening of the sagittal ridge may be initially man-
ial); osteochondral fragmentation of proximal P1; aged conservatively. Palmar lesions may or may not
soft-tissue mineralisation (e.g. suspensory branch, be accessible surgically and OA is often a sequela.
distal sesamoidean ligaments). OCLLs can be managed conservatively or surgi-
cally. Surgical access may depend on cyst location in
Diagnosis a dorsopalmar direction, as indicated radiographi-
OCD of the dorsal sagittal ridge is best evalu- cally. Surgical treatment of OCLLs involves curet-
ated using lateromedial and flexed lateromedial tage of the cyst or injection of corticosteroids into
views. A dorsoproximal/dorsodistal view can help the cyst.
skyline the dorsal sagittal ridge in the forelimb.
Radiographic changes include flattening of the sag- Prognosis
ittal ridge, subchondral bone lucency and fragmen- OCD of the dorsal sagittal ridge has a good progno-
tation. Ultrasonography is also useful in assessment sis. Palmar lesions carry a guarded prognosis. OCLLs
of the sagittal ridge. Assessment of the other joints is have a fair prognosis following debridement. The
also recommended. presence of OA will reduce the outcome.
OCLLs can be evaluated through standard radio-
graphic views. Location of the OCLL on laterome- PALMAR/PLANTAR
dial and flexed lateromedial views is important if OSTEOCHONDRAL DISEASE
surgical intervention is planned. Active OCLLs may
also be visualised as increased radiopharmaceutical Definition/overview
uptake on scintigraphy. Palmar/plantar osteochondral disease (POD)
relates to a degenerative condition affecting the
Management distal condyles of the third metacarpal/ metatarsal
Dorsal sagittal ridge lesions can be managed surgi- bone almost exclusively seen in young racing
cally with removal of fragments and debridement of Thoroughbreds.