Objective—To determine the anatomic communications
among compartments within the carpus,
metacarpophalangeal and metatarsophalangeal
joints, stifle joint, and tarsus in llamas.
Sample Population—88 limbs from 22 llamas
necropsied because of reasons unrelated to disease
of the carpus; tarsus; or metacarpophalangeal,
metatarsophalangeal, or stifle joints.
Procedure—1 compartment (randomly assigned) of
each joint was injected with blue latex solution.
Communication between joint compartments was
determined by observation of latex in adjacent compartments
following frozen sectioning.
Results—Of the 44 carpi, 30 (68%) had anatomic
separation between the radiocarpal and middle carpal
joints, whereas the remaining 14 (32%) had communication
between the radiocarpal and middle carpal
joints. In the metacarpophalangeal or metatarsophalangeal
joints, medial and lateral joint compartments
remained separate in 83 of 88 (94%) joints injected.
The tibiotarsal and proximal intertarsal joints communicated
in all tarsi examined, whereas 14 of 38 (37%)
communicated between the proximal intertarsal and
distal intertarsal joints. Communication between the
distal intertarsal and tarsometatarsal joints was
detected in 17 of 25 (68%) specimens; all 4 tarsal
joints communicated in 11 of 42 (26%) specimens
examined. Examination of 33 stifle joints that were
successfully injected revealed communication
between the femoropatellar, medial femorotibial, and
lateral femorotibial joints.
Conclusions and Clinical Relevance—These data
suggest that it is important to determine the joint
communications specific to each llama prior to treatment
of septic arthritis. The metacarpophalangeal or
metatarsophalangeal joint compartments may be
considered separate, although the lateral and medial
compartments infrequently communicate along the
proximal palmar or plantar aspect. (Am J Vet Res 2005;66:1437–1440)