Texas Equine Veterinary Association

www.teva-online.org • Page 24 elbow lameness IN HORSES Lameness originating from the cubital (elbow) joint is relatively uncommon, with the exception of fractures of the ulna. Due to the relative infrequent occurrence of lameness originating from the elbow, treatment is often delayed. DIAgnosIs of eLBoW LAmeness Both a standing musculoskeletal exam and traditional lameness exam are important when attempting to localize lameness in the elbow. Localization can be straightforward when there is associated swelling/heat or pain on palpation; however, in more subtle cases of suspected upper limb lameness, intra-articular anesthesia of the elbow is necessary to confirm clinical suspicion. Acute lameness is typically associated with olecranon fractures/ luxations along with varying degrees of swelling in the affected area. In contrast, no joint effusion can be palpated in subtle lameness originating from the elbow joint because of the extensive musculature overlying the joint. While effusion is not always evident, sensitivity to deep palpation near the lateral aspect of the elbow can sometimes elicit a positive pain response. Less specific signs of elbow lameness include tricep muscle atrophy, pain on extension and/or flexion, and a decreased anterior phase of the stride during the moving musculoskeletal exam. If lameness is suspected to originate from the elbow and musculoskeletal examination does not definitively localize the lameness to the lower limb, intrasynovial anesthesia (IA) of the elbow should be performed. Elbow intra-articular anesthesia: an 18-gauge, 1.5 inch needle should be inserted cranial or caudal to the palpable edge of the lateral collateral ligament of the elbow joint. The joint margin is approximately two-thirds of the distance distal from the lateral epicondyle of the humerus. Approximately 15 to 20 mls of mepivicaine should be deposited into the joint. 1 Following localization of lameness to the elbow region, a medial-to-lateral radiograph should be performed while standing with the affected limb extended cranial, followed by a cranial-to-caudal radiograph. Nuclear scintigraphy (bone scan) is a viable diagnostic modality when survey radiography and/or ultrasonography has been unrewarding. eLBoW: PAthoLogIc conDItIons, tReAtment, AnD PRognosIs ulna fractures The olecranon portion of the ulna is one of the most commonly fractured long bones in both foals and adult horses. In young horses, most olecranon fractures are associated with direct trauma (kicks) or from sudden tensile overload of the triceps from sudden falls during halter breaking or at weaning. In adults there is typically a history of direct trauma due to a kick or fall. Olecranon fractures typically have a dropped-elbow appearance (Figure 1) because of triceps tension apparatus disruption which prevents the horse from fixing the carpus into extension. If mild or no displacement is present, elbow drop severity will be minimal and only slight carpal flexion may be present. In contrast, severe elbow dropping and carpal flexion carpus will be present with marked bone displacement. Soft tissue swelling is commonly located on the caudal aspect of the elbow. Radiographs should be obtained if a fracture is suspected. Following definitive diagnosis of an olecranon fracture, splinting of the affected limb is often necessary to help reduce anxiety and protect the contralateral limb prior to treatment and transport. Prior to splinting appropriate wound care should be performed if an associated wound is present. When splinting an olecranon fracture the carpus should Figure 1. Appearance of a dropped elbow typical of a displaced ulnar fracture. Figure 2. Application of a caudal splint to lock the carpus in extension to reduce anxiety and protect contralateral limb. This is an open olecranon fracture with a wound at the point of the elbow.

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