Arthroscopic approach and intra-articular anatomy of the dromedary camel (Camelus dromedarius) metacarpophalangeal joint.

Objective: To define the metacarpophalangeal joint (MCPJ) anatomy and its relationships to surrounding structures, relevant to dorsal and palmar arthroscopic approaches, and guide technique development in the camel (Camelus dromedarius).

Methods: Dromedary camel cadaver front limbs were collected from either a slaughterhouse or euthanized individuals for this experimental ex vivo study, excluding those with clinically visible MCPJ pathology. Computed tomography and MRI were conducted on 2 MCPJs to determine relationships with surrounding structures and the extent of their synovial cavity following distension. Dorsal and palmar arthroscopic approaches were performed on 16 MCPJs, after which dissection objectified iatrogenic damage.

Results: 8 front limbs were collected. Advanced imaging allowed depiction of all joint particularities, including the prominent dorsal synovial plica, the dorsally flattened metacarpal condyles, and the complete separation of the adjacent MCPJs. Arthroscopic exploration of the dorsal aspect of the MCPJ allowed examination of the articular cartilage (including weight-bearing surfaces) of both distal metacarpus and proximal P1 and access to those areas. Palmar exploration and instrument access to the axial aspect were limited by the available space and shape of the articular surfaces of the sesamoid bone and the sagittal ridge of metacarpus.

Conclusions: MRI and CT studies improved surgical planning and helped with prediction of the limitations of palmar arthroscopic exploration, including the distal aspect of the joint space and access to the axial sesamoid bone.

Clinical relevance: Diagnostic and therapeutic arthroscopy of the MCPJ should advance the understanding and treatment of conditions of this joint in the camel.