Student University of Montreal Saint hyacinthe, Quebec, Canada
Radiographic Study of the Morphological Maturation of the Equine Distal Femur and Proximal Tibia. Wadbled L1, Finck C1, Santschi E2, Beauchamp G1, Richard H1, Laverty S1. 1Université de Montréal, Saint-Hyacinthe, QC, Canada; 2Kansas State University, Manhattan, KS.
Medial femoral condyle subchondral lucencies (MFCSR) occur in young foals with a greater prevalence in the right (R) stifle. Morphological changes and asymmetries of the MFC with maturation may contribute to lucency development. The objective of this study was to assess anatomic risk factors for MFCSR. Study 1: A retrospective review of caudocranial stifle radiographs (n = 251: 128 L and 123 R) of Thoroughbreds aged 3–20 months with (n = 68) or without MFCSR (n = 183) was performed. Anatomical parameters (n = 13) of femoral condyles (FC), femoral intercondylar notch (FIN) and tibial condyles (TC) were measured and compared between groups. Study 2: An additional cohort of 30-day-old foals (n = 29) were prospectively radiographed and assessed similarly. Study 1: Images were available from 251 stifles, 183 without (SR-) and 68 with (SR+) MFCSR. With maturation, a decrease in FIN width (P = 0.004), medial TC eminence (MICET) height and TC intereminence space (P < 0.0001) were identified in the SR- stifles and were not present in SR+ stifles. Significant L-R asymmetries were present for all ages. In left stifles there were greater bicondylar and FIN widths in SR- stifles and greater MICET height in SR+ stifles. In the right stifle, there were greater MFC and intereminence space widths in SR+ stifles. Study 2: No asymmetry was demonstrated. The difference in growth metrics between SR- and SR+ stifles and between left and right stifles may suggest a mechanism for MFCSR formation. Further studies are required to investigate the potential impact of these morphological differences.