## Overview Carpal canal syndrome is compression of structures within the carpal canal (carpal sheath) producing pain and lameness. The canal contains the superficial and deep digital flexor tendons, their accessory ligaments, and the median artery and nerve. Effusion, desmopathy of the accessory ligament of the superficial digital flexor tendon, distal radial osteochondromas, or retinacular thickening can all produce the syndrome. ## Causes Desmopathy of the proximal check ligament is one possible cause. Other causes include radial exostoses, idiopathic tenosynovitis, and trauma. Chronic effusion leads to pressure on the contained soft tissues. ## Diagnosis Forelimb lameness abolished by proximal metacarpal or antebrachial nerve blocks, combined with carpal sheath effusion, is suggestive. Ultrasound is essential to identify the specific lesion within or adjacent to the canal. ## Treatment Rest and controlled exercise for 3 to 6 months, carpal sheath injection, and corrective shoeing are first-line measures. Surgical release or removal of space-occupying lesions is considered when medical management fails. ## Recovery and Prognosis Prognosis is fair to good for many soft-tissue lesions with appropriate rest. Space-occupying bony lesions often require surgery for lasting improvement. ## Prevention No specific prevention is established. Early attention to check-ligament injuries may limit secondary canal compression.
forelimb lameness; swelling of the carpal sheath; pain on carpal flexion; positive proximal limb nerve blocks
## Overview Carpal canal syndrome is compression of structures within the carpal canal (carpal sheath) producing pain and lameness. The canal contains the superficial and deep digital flexor tendons, their accessory ligaments, and the median artery and nerve. Effusion, desmopathy of the accessory ligament of the superficial digital flexor tendon, distal radial osteochondromas, or retinacular thickening can all produce the syndrome. ## Causes Desmopathy of the proximal check ligament is one possible cause. Other causes include radial exostoses, idiopathic tenosynovitis, and trauma. Chronic effusion leads to pressure on the contained soft tissues. ## Diagnosis Forelimb lameness abolished by proximal metacarpal or antebrachial nerve blocks, combined with carpal sheath effusion, is suggestive. Ultrasound is essential to identify the specific lesion within or adjacent to the canal. ## Treatment Rest and controlled exercise for 3 to 6 months, carpal sheath injection, and corrective shoeing are first-line measures. Surgical release or removal of space-occupying lesions is considered when medical management fails. ## Recovery and Prognosis Prognosis is fair to good for many soft-tissue lesions with appropriate rest. Space-occupying bony lesions often require surgery for lasting improvement. ## Prevention No specific prevention is established. Early attention to check-ligament injuries may limit secondary canal compression.
forelimb lameness; swelling of the carpal sheath; pain on carpal flexion; positive proximal limb nerve blocks