Summary
For the first time in veterinary literature, magnetic resonance and arthroscopic features
of a discoid lateral meniscus in a dog are described. A 15-monthold Labrador Retriever
with a history of mild intermittent left hindlimb lameness was referred to our clinic.
Physical examination revealed mild joint effusion of the left stifle and absence of
a cranial drawer motion and tibial compression test. Survey radiographs demonstrated
mild joint effusion and peri-articular new bone formation. Low-field magnetic resonance
tomography of the left stifle joint demonstrated injury of the cranial cruciate ligament
and a discoid lateral meniscus. Two weeks later, arthroscopy revealed a partial tear
of the cranial cruciate ligament with mild synovitis. Furthermore, some fibres inserted
abnormally cranial to the inter-meniscal and cranial tibial ligament of the medial
meniscus. The lateral meniscus was discoid in shape. Subsequent arthrotomy confirmed
the diagnoses. Discoid meniscus is a rare finding in the dog with unknown clinical
relevance whereas it is well known in humans.
A 15-month-old Labrador Retriever with mild left hindlimb lameness, mild joint effusion
of the left stifle but without signs of stifle instability is presented in this report.
Low-field magnetic resonance tomography demonstrated injury of the cranial cruciate
ligament and a discoid lateral meniscus. Subsequent arthroscopy and arthrotomy confirmed
these findings. A literature review on discoid meniscus in humans and in dogs is presented.
Keywords
Discoid meniscus - cranial cruciate ligament - MRI - arthroscopy - dog
