Arthroscopic approaches and intraarticular anatomy of the equine elbow

Periarticular anatomy and techniques for arthroscopic access to the equine elbow were studied in six joints from cadavers. Caudomedial and craniolateral approaches were evaluated subsequently in 11 anesthetized horses. The caudomedial approach was made between the flexor carpi radialis and flexor carpi ulnaris muscle bellies. Most of the caudal articular surfaces of the humeral condyles, the caudal perimeter of the radius, and the trochlear notch and portions of the anconeal process of the ulna could be identified. The voluminous caudal joint capsule cul-de-sac proximal to the anconeal process was readily entered. A 70 degree arthroscope allowed examination of more of the joint recesses and articular surfaces of the olecranon fossa than a 25 degree arthroscope. A second portal for intraarticular instrument manipulation was made caudal and slightly proximal to the arthroscope entry. Entry more proximal than the level of the radiohumeral articulation carried significant risk of damage to the ulnar nerve and collateral ulnar artery and vein. For examination of the cranial regions of the elbow, a craniolateral portal was established cranial to the lateral collateral ligament. An instrument portal was made through the muscle bellies of the extensor carpi radialis or common digital extensor muscles. The cranial articular surfaces of the humeral condyles were readily exposed by extension of the elbow. The weight-bearing articular surface of the radius could not be seen. Eight horses were euthanatized without recovery from anesthesia and the elbows were dissected for examination. Three horses were allowed to recover from anesthesia and were euthanatized on days 3, 30, and 60.(ABSTRACT TRUNCATED AT 250 WORDS)