title: Effect of doxycycline on contralateral canine cranial cruciate ligament rupture. A prospective randomized clinical trial in 69 dogs.
abstract: OBJECTIVE
  To evaluate whether doxycycline administered to dogs with unilateral cranial cruciate ligament rupture (Uni-CCLR) would decrease the risk of contralateral-CCLR (Co-CCLR). To evaluate predictors for Co-CCLR survival. To evaluate if a predisposition of Labrador Retrievers to Co-CCLR exists when compared to other breeds.
  
  
  METHODS
  In this prospective randomized controlled clinical trial, 69 client-owned dogs with Uni-CCLR were randomly assigned to a doxycycline (group-D: 7.5 mg/kg PO BID x 6 weeks) or non-doxycycline (group-ND: negative control). Medical and imaging data, time from Uni- to Co-CCLR and to follow-up were recorded. Statistics included chi-squared test, logistic regression, Kaplan-Meier survival analysis, log rank test, survival curves, and frailty model (p <0.05).
  
  
  RESULTS
  This study included 32 dogs in group-D, and 37 dogs in group-ND. Median follow-up was 54.5 and 61 months, respectively. Contralateral CCLR occurred in 53.1% and 48.6% at medians of 20 and 11 months, respectively. Doxycycline did not significantly decrease the risk of Co-CCLR (p = 0.83). This risk was decreased by 14.2% with each year of age but increased with each increasing kilogram of body weight and each increasing degree of tibial plateau angle by 5.4% and 9.7%, respectively. Labrador Retrievers were not significantly predisposed (p = 0.37).
  
  
  CONCLUSIONS
  At the dose regimen investigated doxycycline does not decrease the risk for Co-CCLR.
authors.affiliation: Dirsko J.F. von Pfeil, Dr.med.vet, DVM, Diplomate ACVS, Diplomate ECVS, Friendship Surgical Services of the, Friendship Hospital for Animals, 4105 Brandywine Street NW, Washington, DC 20016, United States, Phone: +1 202 363 7300, Fax: +1 202 363 7126, E-mail: dvpfeil@yahoo.com.
authors.forename: D J F
authors.initials: DJ
authors.lastname: von Pfeil
authors.forename: J
authors.initials: J
authors.lastname: Sung
authors.forename: J
authors.initials: J
authors.lastname: Barry
authors.forename: K
authors.initials: K
authors.lastname: Hayashi
authors.forename: M R
authors.initials: MR
authors.lastname: Edwards
mesh_terms: D000818:Animals; D016118:Anterior Cruciate Ligament / Q000473:pathology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004283:Dog Diseases / Q000235:genetics / Q000517:prevention & control*; D004285:Dogs; D004318:Doxycycline / Q000494:pharmacology*; D005260:Female; D020022:Genetic Predisposition to Disease; D008297:Male; D012307:Risk Factors; D012421:Rupture / Q000517:prevention & control / Q000662:veterinary*
chemical_list: D000900:Anti-Bacterial Agents; D004318:Doxycycline
keywords: Doxycycline; canine; cranial cruciate ligament rupture; dog; tibial plateau levelling osteotomy