Determination of pelvic limb alignment in the large-breed dog: a cadaveric radiographic study in the frontal plane.
OBJECTIVE
To report a method for radiographic determination of the mechanical axis of the canine pelvic limb and its relationship to the joints and bone axes. To report reference ranges for the relationships between the axes of the pelvic limb and for joint position relative to the pelvic limb axis.


METHODS
Cadaveric radiographic anatomic study.


METHODS
Pelvic limbs (n=101) from normal midsized to large breed dogs; tibiae (n=105) from dogs with cranial cruciate ligament disease (previous study).


METHODS
Extended full-limb radiography was performed and images analyzed to determine: mechanical joint reference angles (femur, tibia), pelvic limb axis, tibiofemoral and metatarsotibial angle, mechanical axis-femur/metatarsus angle, and mechanical axis deviation (MAD) of the stifle/tarsus.


RESULTS
Mean mechanical angles were: lateral proximal femoral (103.7 degrees +/-5.4 degrees ), lateral distal femoral (98.6 degrees +/-2.5 degrees ), medial proximal tibial (92.2 degrees +/-1.8 degrees ), medial distal tibial (95.9 degrees +/-2.2 degrees ), tibiofemoral (9.1 degrees varus +/-2.8 degrees ), metatarsotibial (0.6 degrees valgus +/-2.1 degrees ). Mean mechanical axis-femur and-metatarsus angles were 5.6 degrees (+/-1.7 degrees ) and 2.9 degrees (+/-1.5 degrees ), respectively. Mean MAD of the stifle and tarsus were 3.6% (+/-1.1%) and 1.2% (+/-0.6%), respectively. Tibial angles were not different between dogs with and without cranial cruciate ligament disease.


CONCLUSIONS
Mechanical axes of the canine pelvic limb and their relationship to the joints can be determined by full-limb radiography.


CONCLUSIONS
Techniques and reference ranges may be useful for diagnosis, surgical planning, and postoperative assessment of pelvic limb deformities.
Dismukes
David I
DI
Comparative Orthopaedic Laboratory, Veterinary Medical Teaching Hospital, University of Missouri-Columbia, Columbia, MO, USA. dismukesd@missouri.edu
Fox
Derek B
DB
Tomlinson
James L
JL
Cook
James L
JL
Essman
Stephanie C
SC
D000818:Animals; D017760:Bone Malalignment / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000662:veterinary; D002102:Cadaver; D004285:Dogs / Q000033:anatomy & histology* / Q000502:physiology; D006614:Hindlimb / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D035002:Lower Extremity / Q000000981:diagnostic imaging; D011859:Radiography / Q000379:methods / Q000662:veterinary*; D012016:Reference Values; D016683:Supine Position; D016474:Weight-Bearing / Q000502:physiology*