Sanz Macarena G, Sampson Sarah N, Schneider Robert K, Gavin Patrick R, Baszler Timothy V
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA 99164-6610, USA.
J Am Vet Med Assoc. 2006 Jun 15;228(12):1918-21. doi: 10.2460/javma.228.12.1918.
CASE DESCRIPTION-A 4-year-old Quarter Horse stallion was evaluated because of a 10-month history of moderate (grade 3/5) left forelimb lameness (detectable during trotting over a smooth, hard surface). CLINICAL FINDINGS-No abnormalities were detected in either forelimb via palpation or application of hoof testers; however, lameness was eliminated after administration of a palmar digital nerve block in the left forelimb. Whereas radiography and ultrasonography did not identify any left forelimb foot abnormalities, magnetic resonance (MR) imaging revealed a circumscribed soft tissue mass in the distal aspect of the digital flexor tendon sheath (DFTS) dorsal to the lateral aspect of the deep digital flexor tendon. Subsequently, the left forelimb DFTS was injected with local anesthetic, which resulted in 90% improvement of the horse's lameness. TREATMENT AND OUTCOME-The distal aspect of the left forelimb DFTS was evaluated tenoscopically. The mass was removed under tenoscopic guidance, after which the distal digital annular ligament was transected. The horse received phenylbutazone orally for 10 days, and the left forelimb DFTS was injected with hyaluronic acid and methylprednisolone acetate 7 days after the surgery. Following a rehabilitation program, the horse was returned to full training at 6 months after surgery and competed successfully during a 2-year follow-up period. CLINICAL RELEVANCE-Use of MR imaging should be considered in all lame horses for which a definitive diagnosis cannot be made via radiography, ultrasonography, or other imaging techniques, especially when the lameness has been localized to a specific anatomic region by use of diagnostic anesthesia.
病例描述——一匹4岁的夸特马种公马因左前肢中度（3/5级）跛行10个月（在光滑坚硬地面上小跑时可检测到）而接受评估。临床检查结果——通过触诊或使用蹄诊器在前肢均未发现异常；然而，在对左前肢进行掌侧指神经阻滞注射后跛行消失。虽然X线摄影和超声检查未发现左前肢足部有任何异常，但磁共振成像显示在指深屈肌腱外侧背侧的指屈肌腱鞘远端有一个边界清晰的软组织肿块。随后，对左前肢指屈肌腱鞘注射局部麻醉剂，马的跛行改善了90%。治疗与结果——通过关节镜检查评估左前肢指屈肌腱鞘远端。在关节镜引导下切除肿块，然后切断远侧指环形韧带。马口服苯基丁氮酮10天，并在手术后7天对左前肢指屈肌腱鞘注射透明质酸和醋酸甲基泼尼松龙。经过康复计划，马在手术后6个月恢复全面训练，并在2年的随访期内成功参赛。临床意义——对于所有通过X线摄影、超声检查或其他成像技术无法做出明确诊断的跛马，尤其是当通过诊断性麻醉已将跛行定位到特定解剖区域时，应考虑使用磁共振成像。
