Cruciate Ligament Disease by Dr. Kevin Roeser
Your dog’s knees, just like your own, are supported and stabilized by several ligaments. The cranial cruciate ligament of dogs is analogous to the anterior cruciate ligament or ACL of humans. This ligament keeps the tibia from sliding too far forward and limits internal rotation of the knee. Dogs or cats who are suffering from acute damage to the cranial cruciate ligament typically present to our hospital with non- or partially weight-bearing lameness of the affected hind leg.
In many cases, a thorough orthopedic examination will raise suspicion of a cruciate ligament injury. Most pets are painful upon palpation of the affected knee, and your veterinarian may identify swelling in the area or a soft click that typically represents secondary damage to the associated meniscus. Chronic cases of cruciate ligament disease may also exhibit evidence of degenerative joint disease or thickening of other fibrous structures associated with the knee. In either case, your doctor will evaluate for presence of a “cranial drawer” or “tibial thrust” – two actions of the knee that suggest that the function of the cruciate ligament has been compromised. Radiographs (x-rays) of the area will help to rule-out other potential causes of lameness as well as to characterize the extent of secondary changes. While x-rays cannot identify the cruciate ligaments specifically, there are several classic signs on x-rays that are supportive of cruciate ligament disease.
Management of cruciate ligament injuries may involve surgical or medical treatment. For most cases, surgical management provides the best stabilization of the joint and the best long-term prognosis.
Unfortunately, there is no current surgical repair method that can restore a cruciate ligament after it has been damaged. Instead, surgical corrections are aimed at stabilizing the knee in other ways. These techniques include:
- Extracapsular Repair: This technique is often elected for small dogs and cats as it is unlikely to provide adequate support for larger patients. The surgical repair procedure involves the placement of a thick monofilament suture or surgical cable outside of the joint to mimic the function of the cruciate ligament. It provides stabilization, but degenerative joint disease (arthritis) is still likely to develop. Rarely, this surgical repair can fail if the suture or cable subsequently breaks.
- Tibioplasty: Large dogs typically do better with a more substantial surgical procedure. Doctor preferences vary, but the Tibial Plateau Leveling Osteotomy (TPLO) and Tibial Tuberosity Advancement (TTA) procedures are most often recommended. Both options involve surgical adjustment of the proximal tibia in an attempt to minimize sliding forces. These procedures are best performed by a board-certified veterinary surgeon. These types of surgeries provide the best stabilization of the joint, though degenerative joint disease (arthritis) can still develop. These surgeries rarely fail, but there is a small percentage of patients that do not recover as well as expected.
Given adequate time and rest, many dogs can develop sufficient stifle stabilization without surgical intervention. Again, our goals are not to promote specific healing of the cruciate ligament, but to allow other soft tissue structures in and around the knee to scar down and provide additional support. This process typically takes 4-8 weeks, during which patients should be strictly limited with regards to their exercise habits. Short leashed walks to urinate and defecate are acceptable, but avoid any running, jumping, or playing. It is best to confine patients to a small room or crate/kennel when unsupervised to avoid injury during your absence. Non-steroidal anti-inflammatory medications and other pain-relieving medications are used during this period to maintain patient comfort and support healing. Joint supplements (glucosamine/chondroitan and fish oils), laser therapy, and acupuncture can be beneficial as well. Medical management does not provide the same degree of stabilization as surgical repair, so most patients will develop significant arthritis if medical management is chosen alone.
Cranial cruciate ligament injuries can be the result of traumatic injury to the affected leg or can be related to chronic degenerative disease in certain breeds. These injuries may also occur secondary to other orthopedic conditions of the knees, including medial patellar luxation or inflammatory/infectious joint disease. Maintaining your pet at an optimal weight and promoting regular exercise are two important factors in preventing orthopedic disease. Your veterinarian can help identify other risk factors for your individual pet. Unfortunately, most dogs develop bilateral cruciate disease, so any possible preventative steps should be pursued to prevent disease in the opposite leg.
Happy Easter: Avoid The Chocolate Easter Bunny
Most people enjoy chocolate, and not surprisingly, most pets do too! Unfortunately, chocolate Easter bunnies and Cadbury eggs can be toxic to pets and can lead to severe clinical signs including vomiting, diarrhea, restlessness, hyperactivity, tremors, seizures, ataxia (‘drunkenness’), increased heart rate, heart arrhythmias, increased blood pressure, increased body temperature, difficulty breathing, and even death.
The toxic compounds in chocolate are methylxanthines – this includes both theobromine and caffeine. These compounds inhibit cellular receptors, stimulate the central nervous system, and enhance cardiac and skeletal muscle contractility. In addition, the high fat content in chocolate leads to local gastrointestinal irritation (vomiting and diarrhea), and in severe cases, a serious disease called pancreatitis. Clinical signs occur within 12 hours, but most pets will begin exhibiting signs within 1-4 hours of ingestion.
Different types of chocolate have different amounts of theobromine and caffeine. While we generally consider 100 mg/kg to be a toxic dose, some patients will exhibit clinical signs at a dose as low as 20 mg/kg. However, often, we don’t know the type or amount of chocolate that was ingested, so it is best to proceed as if the ingestion was the worst-case scenario.
Treatment depends on the amount of methylxanthines ingested, the time of ingestion, and the patient’s clinical signs. If recent ingestion occurred, vomiting is induced to evacuate the stomach. In severe cases, sedation and gastric lavage with a stomach tube may be performed to evacuate the stomach contents. Activated charcoal is administered to bind the toxins in the gastrointestinal tract. Fluid therapy, anti-vomiting medications, gastrointestinal protectants, and a bland diet may be prescribed. In severe cases, patients require intensive care including intravenous fluid therapy, continuous EKG monitoring, oxygen support, urinary catheterization, and intravenous medications to manage seizures, cardiac arrhythmias, and abnormal respirations.
If treated promptly, most patients with chocolate toxicity recover, but it is important to understand that chocolate ingestion can lead to severe complications and even death. It is best to avoid chocolate ingestion in your pet. During the holidays when chocolate is abundant, make sure it is kept out of reach of your pet. If you suspect ingestion, contact your veterinarian immediately.
Dr. Soucheray's At Home Veterinary Care
We are happy to introduce to you Dr. Sandra Soucheray with Dr. Soucheray’s At Home Veterinary Care. Dr. Soucheray is a 2002 graduate of the University of Minnesota College of Veterinary Medicine. She worked in private practice for years before opening her own mobile veterinary practice. Dr. Soucheray will be one of the doctors involved in our Hospice & Palliative Care Program network that will launch in May. She will also provide relief veterinary services at St Francis from time to time. She will be seeing patients at St Francis on Friday, May 19th -- stop in and meet her!
Animal Emergency & Referral Center: Oakdale
As a growing percentage of veterinary practices are being consolidated into large corporate entities, we strive to create partnerships with smaller veterinarian-owned facilities. We encourage you to consider Animal Emergency & Referral Center in Oakdalefor all of your pets’ specialty needs. They offer dermatology, cardiology, dentistry, internal medicine, critical care, and physical rehabilitation in addition to their emergency services. John Nielson, CVT-VTS, CVPP, CCRP in the Sport & Strength Department is working closely with our team at St Francis Integrative Services to provide integrative care to our patients.
Joy Session and Sarah Beth Photography
We are excited to be involved with the Joy Session project. You’ve seen her talent displayed throughout both of our St Francis locations. But now, Sarah Beth from Sarah Beth Photography is teaming up with other photographers as well as veterinarians, businesses, and other animal health care providers to offer a website dedicated to the aging pet and hospice/palliative care. We at St Francis Animal & Bird Hospital are very excited to be one of the resources for Hospice & Palliative Care on the Joy Session website. To learn more, visit the Joy Session website.
Pet Project Rescue Fundraiser
Join the St Francis team at the 9th Annual Pet Project Rescue fundraiser at the Bauhaus Brewery at 1315 Tyler St NE in Minneapolis on Sunday, April 30th, 12-4 pm. St Francis Animal & Bird Hospital is proud to be a presenting sponsor this year. Click here to visit their website and purchase tickets to this event.
St Francis' 25th Anniversary Open House
Mark your calendar for our 25th Anniversary Open House celebration on Sunday, September 10th, 1-4 pm. Check out our St Francis Facebook page on the 25th of each month for contests and giveaways. Thank you to everyone who has been part of the St Francis family for all these years!
Dr. Jennifer Blair: Cuba
Dr. Blair recently traveled to Cuba with the American Board of Veterinary Practitioners to discuss veterinary medicine with local practitioners and government officials. Their group also spent time at ANIPLANT, an organization dedicated to the protection of animals in Cuba. To learn more about ANIPLANT, click here.