R upture of the cranial cruciate ligament (RCCL) is the most common cause of lameness in dogs. 1 Rupture of the CCL causes stifle joint instability, joint inflammation, and lameness. Although treatment options include surgical and nonsurgical management, surgery is generally recommended for dogs > 15 kg (33 lb) because it provides for an improved prognosis. 2 This contributes to the increased cost for RCCL manage- ment because the breeds of dogs that are most predis- posed to RCCL are comparatively large in size. 3,4 Veterinarians have dozens of surgical techniques to choose from to treat RCCL, and the cost to the owner depends on several factors. Expertise of the surgeon, surgical technique performed, and region of the coun- try would also be expected to factor heavily into cost comparisons. Unfortunately, even with surgical man- agement, osteoarthritis develops in most patients. 5-7 Although the severity of osteoarthritis of the stifle joint does not correlate with the severity of lameness, 8 many patients do require treatment for osteoarthritis and this treatment may be required for the duration of the patient’s life. Nonsteroidal anti-inflammatory drugs (NSAIDs) in combination with weight management, physical therapy, and disease-modifying drugs are all nonsurgical treatments commonly used for osteoarthri- tis in dogs. Although RCCL is an exceedingly prevalent dis- ease, particularly in some breeds of dogs, a only a limit- ed amount of research funding is available for investi- gators to explore the cause of RCCL and establish the best treatment options for patients. This limitation in funding may be attributable, in part, to the fact that the economic impact of RCCL is not considered substan- tial and funding agencies prioritize research in this field comparatively low or that the economic impact of RCCL is high and agencies are not aware of the eco- nomic impact. Therefore, we hypothesized that RCCL treatment is costly. The purpose of the study reported here was to estimate the economic impact to veterinary clients for the medical and surgical treatment of RCCL in dogs for the year 2003. Materials and Methods Survey—Two groups of veterinarians were surveyed. First, all diplomates of the American College of Veterinary Surgeons (ACVS) indicating that their area of surgical emphasis was small animal orthopedic surgery or small ani- mal general and orthopedic surgery (n = 501) were surveyed. This mailing list was purchased from the ACVS after they had approved both the cover letter and survey. The cover letter and survey were mailed directly by the authors. Second, 4,000 veterinarians that had indicated to the AVMA that their professional area was small animal practice exclusive or mixed practice (at least 80% small animal) were randomly chosen. This mailing list was purchased from the AVMA, through the list manager b for the AVMA, after the AVMA JAVMA, Vol 227, No. 10, November 15, 2005 Scientific Reports: Original Study 1 SMALL ANIMALS Estimate of the annual economic impact of treatment of cranial cruciate ligament injury in dogs in the United States Vicki L. Wilke, DVM, DACVS, Duane A. Robinson, DVM; Rich B. Evans, PhD; Max F. Rothschild, MS, PhD; Michael G. Conzemius, DVM, PhD, DACVS Objective—To estimate the economic impact to vet- erinary clients for the medical and surgical treatment of rupture of the cranial cruciate ligament (RCCL) in dogs for the year 2003. Design—Economic impact survey. Sample Population—501 diplomates of the American College of Veterinary Surgeons (ACVS) indi- cating that their area of surgical emphasis was small animal orthopedic surgery or small animal general and orthopedic surgery and 4,000 veterinarians indicating to the AVMA that their professional area was small animal practice exclusive or mixed animal practice (at least 80% small animal). Procedure—Veterinarians were surveyed concerning the cost for medical and surgical treatment of RCCL for 2003. The economic impact was calculated by multiplying the number of RCCL surgeries performed by the mean cost of surgery. This was added to the number of RCCL cases managed medically multiplied by the mean cost of medical management. This esti- mate for survey responders was extrapolated to the total number of veterinarians in the study population for the ACVS or AVMA, respectively. Results—Estimates for the total cost of surgery were $171,730,134.72 and $1,020,167,907 for veterinarians in the ACVS and AVMA populations, respectively. The cost of medical management was $2,885,687.86 and $126,558,155.16 for veterinarians in the ACVS and AVMA populations, respectively. After combining the ACVS and AVMA populations, we estimated that own- ers spent $1.32 billion for the treatment of RCCL in the United States in 2003. Conclusions and Clinical Relevance—RCCL is a prevalent, costly injury. Results may motivate veterinary and consumer agencies to prioritize funding for a better understanding of the injury. (J Am Vet Med Assoc 2005; 227:xxx–xxx) JAVMA–05-03-0160–OS–Wilke–0tab–0fig–KMC–DCO From the Department of Animal Sciences and Center for Integrated Animal Genomics (Wilke, Rothschild), and the Department of Veterinary Clinical Sciences, College of Veterinary Medicine (Wilke, Robinson, Evans, Conzemius), Iowa State University, Ames, IA 50011-1250. Supported in part by the Iowa State University Veterinary Orthopedic Research Laboratory, Iowa Agricultural and Home Economics Experiment Station, and Hatch and State of Iowa Funding. Presented in part at the 31st Veterinary Orthopedic Society Annual Conference, Big Sky, Mont, February 2004. Address correspondence to Dr. Wilke.