title: Radiographic landmarks for measurement of cranial tibial subluxation in the canine cruciate ligament deficient stifle.
abstract: OBJECTIVE
  The primary objective was to develop a repeatable radiographic technique for assessment of cranial tibial subluxation (CTS) and test the intra-observer and inter-observer repeatability of the chosen landmarks. A secondary objective was to determine the effects of digital radiographic magnification on CTS measurement repeatability.
  
  
  METHODS
  Twenty-three normal canine pelvic limbs were used to determine the magnitude of CTS before and after transection of the cranial cruciate ligament. Mediolateral radiographs were taken with and without fiduciary markers in place. Three investigators measured the CTS using radiographically visible anatomic landmarks at two different magnifications. The total observed variabilities were assessed by inter-observer and intra-observer differences. Paired t-tests were used to determine the effect of magnification and marker presence on CTS measures.
  
  
  RESULTS
  Measurement of the CTS from the caudal margin of the intercondylar fossa on the femur to the intercondylar eminence was the most repeatable. Poor correlation between the anatomic landmarks and the fiduciary bone markers was observed. We found no effect of magnification or presence or absence of bone markers on measurement of CTS.
  
  
  CONCLUSIONS
  Cranial tibial subluxation can be detected with the most repeatability by measuring between the caudal margin of the intercondylar fossa and the intercondylar eminence. Magnification of the digitized radiographic image had minimal effect on repeatability. This technique can be used for in vivo analysis of the canine cruciate ligament deficient stifle joint.
authors: Western College of Veterinary Medicine, Department of Small Animal Clinical Sciences, Saskatoon, Saskatchewan, Canada. rplesmandvm@gmail.com
authors: R
authors: R
authors: Plesman
authors: A
authors: A
authors: Sharma
authors: P
authors: P
authors: Gilbert
authors: J
authors: J
authors: Campbell
authors: J D
authors: JD
authors: Johnston
authors: C
authors: C
authors: Shmon
authors: K
authors: K
authors: Linn
mesh_terms: D000818:Animals; D016118:Anterior Cruciate Ligament / Q000473:pathology*; D001696:Biomechanical Phenomena; D002102:Cadaver; D004285:Dogs / Q000293:injuries*; D004204:Joint Dislocations / Q000000981:diagnostic imaging / Q000473:pathology / Q000662:veterinary*; D015588:Observer Variation; D011859:Radiography; D013264:Stifle / Q000000981:diagnostic imaging*; D013679:Technology, Radiologic / Q000706:statistics & numerical data / Q000662:veterinary; D013977:Tibia / Q000000981:diagnostic imaging* / Q000473:pathology