SURGERY Article sponsored by Petcam ® Cranial Cruciate Ligament Injuries in Dogs Where to go next? By William Snell, DVM, DACVS (Small Animal) Canine cranial cruciate ligament (CCL) disease is the most common cause of hindlimb lameness seen in our canine patient population. 1. Rupture of the ligament may occur as a traumatic avulsion, an acute tear from excessive strain or more commonly as a progressive degenerative disease resulting in partial or complete ligament rupture. While any dog breed can suffer from the condition, there are certain breeds that appear to be predisposed. Patients may present at any age, and both neutered and female patients may be over-represented. 2, 3 Timing of neuter has not been shown to correlate with this disease, and the disease is thought to be multifactorial. We understand certain genetic, developmental and environmental factors play a role in the degenerative process, including limb anatomic conformation, tibial plateau angle, body condition and activity type, but all factors have not yet been identified. Since the degenerative form of the disease is thought to be progressive in nature, patients may present at varying ages and stages of ligament integrity. It has also been stated that 30% to 40% of patients who tear one cruciate ligament are predisposed to tearing the contralateral limb within one or two years. 4 The cranial cruciate ligament is important to neutralizing cranial tibial subluxation, internal rotation and hyperextension of the stifle. The ligament itself consists of two bands: craniomedial and caudolateral. vet360 Issue 03 | JULY 2018 | 6 Figure 1: Right Stifle, lateral view. The infrapatellar fat pad is reduced as a result of joint effusion and or capsular thickening. Mild osteophytes are seen on the distal femur, patella and tibial condyles. All images courtesy of Dr. William Snell.