Trochlear inclination angles in normal and dysplastic knees.
Trochlear morphology impacts component position in patellofemoral arthroplasty. We devised a measurement of the trochlear inclination angle (TIA) and determined the average TIA in normal and dysplastic knees. Three hundred twenty-nine consecutive magnetic resonance imagings of normal and dysplastic knees were evaluated. The TIA was measured by 2 reviewers. The Student t test was used, and intraobserver reliability measurements were made. The mean TIA in normal and dysplastic knees was internally rotated 11.4° (range, 6°-20°) and 9.4° (range, 4°-15°), respectively. The mean TIA did not differ significantly by sex or age. Trochlear inclination angles in both normal and dysplastic knees tend toward internal rotation. Positioning a trochlear patellofemoral arthroplasty component flush with the articular surface of the native trochlea would result in internal rotation malposition.
Department of Orthopaedic Surgery, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
Atul F
AF
Kamath
Thomas R
TR
Slattery
Ashley E
AE
Levack
Chia H
CH
Wu
J Bruce
JB
Kneeland
Jess H
JH
Lonner
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee; D001847:Bone Diseases / Q000175:diagnosis*; D005260:Female; D005269:Femur; D006801:Humans; D007719:Knee Joint; D007720:Knee Prosthesis; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D055815:Young Adult