Complete or partial disruption of the cranial cruciate ligament (CCL) causes stifle joint instability, leading to a cascade of inflammatory and pathologic changes. When evaluating a dog for CCL injury, gait analysis should be performed with adequate footing and enough room to observe the dog standing still, walking, trotting, running, sitting, and rising. It is helpful to start the orthopedic examination with the patient standing, which will help with palpating for subtle changes in the limbs. The tibial compression test can also be performed in standing patients and is especially helpful when examining larger animals. Medial meniscus injury commonly occurs in conjunction with CCL pathology, and the patient should be assessed for such pathology. Diagnostics may include radiographs, magnetic resonance imaging, and arthroscopy. Surgical stabilization is indicated in most patients with CCL pathology, although conservative treatment or use of a stifle brace may be elected for some patients. More recent surgical techniques include the tibial plateau leveling osteotomy (TPLO) and tibial tuberosity advancement procedures. Numerous studies have indicated rehabilitation therapy after CCL surgery yields positive benefits. Interventions during rehabilitation include cryotherapy, laser therapy, neuromuscular electrical stimulation, range of motion and stretching exercises, and various therapeutic exercises. Rehabilitation guidelines are structured to get patients to preinjury activity levels as quickly and safely as possible, but should be individualized for the patient.

COMMENTARY:
Stifle injuries are extremely common in small animal practice and this article provides a thorough and practical discussion of evaluating canine patients for such pathology. Discussion of surgical treatment is only briefly touched upon, which is not necessarily a disadvantage for most general practitioners as so many of these patients are referred to orthopedic surgeons. Where the presentation really shines is in its discussion of rehabilitation therapy, where detailed guidelines on the types of interventions used, as well as how and when to use them, will be presented. The addition of tables that include home exercise programs in both the acute and advanced phases are a real plus; and clinicians will find them extremely useful when helping guide owners through their dogs' rehabilitation phases after CCL surgery.

The canine stifle. Canapp SO. Clin Tech Small Anim Pract 22:195-205, 2007.