Page 1 of 5 Having Trouble Viewing this Email? Click Here You're receiving this email because of your relationship with Aspen Meadow Veterinary Specialists. Please confirm your continued interest in receiving email from us. You may unsubscribe if you no longer wish to receive our emails. May 2011, Issue 31 What's New at AMVS Our Continuing Education (CE) class on Surgical Review and Wet Lab, featuring a lecture by Dr. Felix Duerr, Tips and Techniques for Managing Juvenile Hip Disease, was quite successful. In This Issue What's New at AMVS The Utility of TPLO for Partial Cranial Cruciate Ligament Tears Thank you to all who attended and for the feedback we received! Please join us for our next CE in June, presented by Dr. Wendy Yaphe and Dr. Jackie Campbell, where we will be focusing on Canine Puritis & Otitis; additional information will be sent out later this month. The Utility of TPLO for Partial Cranial Cruciate Ligament Tears Robyn Read, DVM, Surgical Specialist (Intern) Practice Points for your next case: Recent studies have shown that TPLO is protective of remaining CCL fibers and may prevent intra-articular cartilage damage. Arthroscopy is used as a minimally invasive means to determine a definitive diagnosis of a partial CCL tear. Bilateral partial CCL tears can present with no reportable lameness (per owner) because it can be difficult for owners and veterinarians to appreciate a mild lameness when both hind limbs are affected. Unfortunately there is no good non-surgical option for partial CCL tears that will result in return to In addition to our regular ER hours, AMVS is providing emergency and critical care services to your patients: Fridays, all day 303-678-8844
Page 2 of 5 function, improve pain and lameness scores, and possibly halt further damage to the CCL and intraarticular structures like a TPLO. Partial CCL tears have never reportedly resolved on their own. Clinically we have found that the majority of partial CCL tears do develop into complete CCL tears regardless of non-surgical measures taken to prevent progression of stifle disease. Cranial cruciate ligament (CCL) injury is one of the most common causes of pelvic limb lameness in dogs. We, veterinarians, are becoming very good at diagnosing complete CCL tears based on history, orthopedic exam and radiographic evidence. Veterinary surgeons agree that the return to optimal function after CCL injury is best accomplished by surgical intervention. Tibial plateau leveling osteotomy (TPLO) is the commonly preferred technique. Partial CCL tears, however, present a more complex issue for all veterinarians as they can be more difficult to diagnose and treatment guidelines are still being developed. Mounting evidence has shown that early TPLO is protective of remaining CCL fibers and may prevent intra-articular cartilage damage.1 Unilateral, partial CCL tears often present as intermittent, chronic hind limb lameness. Orthopedic exam findings show stifle effusion with pain on hyperextension of the affected stifle. Radiographs will often only reveal stifle effusion, although osteophytosis is a common finding as well. Archives of our past newsletters containing timely and useful medical information are on our website. AMVS is: PACE certified, LEED certified, and a zero-waste facility. Arthroscopy is used as a minimally invasive means to determine a definitive diagnosis of a partial CCL tear. Arthroscopy is often performed to assess and treat the CCL and meniscus, and to assess cartilage health as well as other intra-articular structures. If a partial CCL tear is found at the time of arthroscopy a TPLO is performed immediately. During arthroscopy we often find early arthritic changes in CCL deficient stifles that were not evident radiographically. An even greater diagnostic challenge is the dog that presents with bilateral partial CLL tears or an early tear in the contralateral. Bilateral partial CCL tears can present with no reportable lameness (per owner) because it can be difficult for owners and veterinarians to appreciate a mild lameness when both hind limbs are affected. Exercise intolerance, stiffness, and hip dysplasia are often the presenting complaints made by owners of dogs with bilateral, partial CCL tears. An orthopedic exam of bilateral partial CCL tears will reveal bilateral effusion (which can be difficult to appreciate without a 'normal' stifle with which to compare an effusive stifle), and pain on hyperextension.
Page 3 of 5 These dogs can have no lameness up to a grade 1-3/5 lameness (see lameness chart) in one or both stifles. Radiographs are often necessary to make a diagnosis of bilateral partial CCL tears. They can also be very helpful to rule out other causes of bilateral hind limb lameness (stifle OCD, hip dysplasia, etc.). Hip dysplasia is almost always bilateral, so if a dog presents with a unilateral hind limb lameness, look for another cause for the lameness. A recent study published by Hulse et al.1 described the long -term arthroscopic appearance of the intra-articular structures of the stifle after TPLO. The study was divided into two groups: Group 1 dogs (17 stifles) had a partial CCL (early fiber tearing) while a substantial part of the remaining CCL appeared and probed normally at the time of the TPLO. Group 2 dogs (46 stifles) had either complete CCL disruption or a partial CCL tear, with the remaining CCL judged incompetent based on appearance and probing; a functionally complete tear. On repeat arthroscopy, intra-articular structures of the Group 1 stifles had normal to near normal appearance; the CCL appeared similar to the initial surgery except that torn CCL fibers had reabsorbed. Most stifles in Group 2 had increased pathologic change at repeat arthroscopic exam compared with initial arthroscopic appearance. In 32 stifles, the caudal cruciate ligament had some degree of fraying, and was completely ruptured in 3 stifles. Of the 27 dogs in Group 2 with normal menisci and no meniscal release at initial surgery, 10 stifles had medial meniscal injuries. There were now visible cartilage lesions not present at the time of initial surgery in 39 joints. These findings suggest that TPLO has a protective effect on the remaining CCL and intra-articular structures when performed early (TPLO for partial tears). Eliminating cranial tibial thrust by performing a TPLO lowers the strain on the CCL, reducing the possibility of further tearing. Additionally, the remaining functional CCL may continue to give some stability to the joint (cranio-caudal, varusvalgus, rotational), as it would if it were completely intact. Hulse et al. hypothesized that the remaining functional CCL maintains the relationship of the femoral condyles relative to the tibial plateau (centers the condyles within the menisci). This may account for the decreased incidence of meniscal injury and articular cartilage damage for the Group 1 stifles. Unfortunately, there is no effective non-surgical option to repair partial CCL tears. A TPLO is the best option that will result in improved function, improved pain and lameness
Page 4 of 5 scores, and possibly halt further damage to the CCL and intra-articular structures. Partial CCL tears have never reportedly resolved without surgical intervention. Clinically, we have found that the majority of partial CCL tears develop into complete CCL tears, regardless of nonsurgical measures taken to prevent progression of stifle disease. Additionally, there is no scientific research published to-date that shows rest, stifle braces, or physical therapy can treat or prevent the progression of partial CCL tears. We, as surgical specialists, see a lot of cases that have undergone non-surgical management of a partial CCL tear that ultimately require surgical intervention. The question owners start to ask is if these dogs underwent a TPLO when the lameness was first diagnosed, could further arthritic changes & meniscal damage been prevented and could the remaining functional CCL been preserved? We see substantially fewer meniscal injuries with partial CCL tears than with complete tears. Several studies have found the progression of postoperative osteoarthritis is slowed if a menisectomy need not be performed due to meniscal damage. With the intent of preserving the menisci and with the recent finding that early intervention with a TPLO may decrease stifle morbidity, we recommend a TPLO be performed as soon possible after a diagnosis of a partial CCL tear, in order to obtain optimal stifle function. References: Hulse D., Beale B., Kerwin S., Veterinary Surgery 39 (2010) 350-354. Aspen Meadow Veterinary Specialists Lameness Scale Grade 1 - animal may shift weight slightly off the leg at a stance but no obvious lameness at a walk or trot; lameness barely noticeable Grade 2 - animal uses leg all of the time at a walk and trot but lameness is obvious; animal definitely shifts weight off leg at a stance but does support weight well Grade 3 - animal will use leg most of the time but sometimes skips a step; shifts weight off leg at a stance and does not support significant weight
Page 5 of 5 Grade 4 - animal will use leg but often carries the leg; leg use for balance only at a stance; "toe-touching" lame Grade 5 - animal does not even toe touch at a stance (i.e. fracture lame); completely non weight-bearing Thank you for your continued support. -Aspen Meadow Veterinary Specialists 104 S. Main Street Longmont, CO 80501 303-678-8844 (p) 303-678-8855 (f) info@aspenmeadowvet.com www.aspenmeadowvet.com Forward email This email was sent to info@aspenmeadowvet.com by info@aspenmeadowvet.com Update Profile/Email Address Instant removal with SafeUnsubscribe Privacy Policy. Aspen Meadow Veterinary Specialists 104 South Main Street Longmont CO 80501