Summary
For a suture that spans a joint to provide support without limiting range of motion,
its attachment points on either side of the joint must remain the same distance from
each other from full extension to full flexion. The effect of location of the tibial
crest attachment for a fabello- tibial crest suture was studied in seven canine cadaveric
stifles. The distance from a fabella marker to each of 11 tibial markers was determined
from radiographs of each limb, as it progressed from 150° to 130°, 105°, 90°, 65°
and 45° of flexion. The marker locations that were more proximal and cranial on the
tibial crest had the least percent change in distance. The effect of anchoring the
suture to the femur at a site other than the fabella was investigated using the same
radiographs. Five marks were placed in a grid on the caudal portion of the femoral
condyle and supracondylar region. The mean percent change in length from each femoral
point to the five more proximal and cranial tibial markers was determined. The least
change in length occurred for those femoral points located close to the origin of
the cranial cruciate ligament. Locations more proximal or cranial resulted in large
changes in length, particularly when matched with less ideal tibial locations. Although
this study does not directly examine length changes in sutures, it demonstrates that
there are some locations for the origin and insertion of an extracapsular suture that
are associated with less length change than others, and also forms the basis for future
investigations.
Keywords
Canine cranial cruciate ligament - extracapsular suture - length - isometry
