Computed Tomographic Arthrography of the Intercarpal Ligaments of the Equine Carpus

Abstract

Injuries of the intercarpal ligaments are an important cause of lameness in performance horses. The purpose of this prospective cadaver study was to determine whether computed tomography (CT) arthrography would be a feasible method for visualizing and characterizing intercarpal ligaments in the horse. One cadaver limb from each of eight nonlame horses was collected immediately after euthanasia. For each limb, overlapping 2.0 mm CT images were acquired before and after injection of iodinated contrast medium into the antebrachiocarpal joint, middle carpal joint, and carpal sheath. Spin echo magnetic resonance imaging (MRI) sequences were acquired in three planes using a 1.5 Tesla MRI scanner in three limbs. Following MRI, colored resin was injected into the synovial structures of these three limbs, limbs were frozen, and anatomic sections were obtained in three planes. Findings from CT arthrograms were compared to findings from precontrast CT, MRI, anatomic slices, and arthroscopy. Medial and lateral palmar intercarpal ligaments, radiocarpal and transverse intercarpal ligaments, and palmar carpal ligament were visible in CT arthrograms of all limbs. The proximal and distal entheses of all ligaments were readily identifiable. Findings indicated that CT arthrography is feasible for visualizing intercarpal ligaments and may be a useful adjunct imaging technique for diagnosing lameness due to suspected carpal ligament injury in horses.

Biomarkers for equine joint injury and osteoarthritis

“…It appears that CTO density patterns can characterize insidious disease processes, such as palmar osteochondral disease. Intra‐articular application of contrast has also been used and provides critical information concerning soft tissues of joints, especially those such as the equine femorotibial joint that can rarely be imaged using MRI . Dual energy CT has also been studied and appears to have value in characterization of soft tissues and detection of bone marrow edema …”

The challenge of diagnosing soft tissue injuries in the palmar aspect of the carpus

“…Although MR images of some carpi were obtained by Gray et al . (), comparison of computed tomographic arthrography and MR images was not within the scope of their study. In our opinion, the fibre structure of the palmar carpal ligaments can be better evaluated on MR images than on computed tomographic images; moreover, MRI can be performed in a standing sedated horse, while computed tomography of the carpus requires general anaesthesia.…”

“…A recent study described computed tomographic arthrography of the intercarpal ligaments of the carpus (Gray et al . ). Computed tomographic arthrography allowed good visualisation of the medial and lateral intercarpal ligaments, radiocarpal ligament, transverse intercarpal ligaments and the PCL.…”

Intra‐articular soft tissue injuries in the carpus

“…A recent study described computed tomographic arthrography of the intercarpal ligaments of the carpus (Gray et al . ). Computed tomographic arthrography allowed good visualisation of the medial and lateral intercarpal ligaments, the radiocarpal ligament, the transverse intercarpal ligaments and the palmar carpal ligament; the carpometacarpal ligaments were not assessed.…”

“…These ligaments can be visualised by MRI (Nagy and Dyson ) and computed tomography (Gray et al . ), but to date no MRI or computed tomographic diagnosis of injuries to the palmar intercapal ligaments have been published.…”