Victor R Carlson1, Frances T Sheehan1, Aricia Shen1, Lawrence Yao2, Jennifer N Jackson1, Barry P Boden3. 1. Functional and Applied Biomechanics Section, Department of Rehabilitation Medicine, National Institutes of Health, Bethesda, Maryland, USA. 2. Department of Radiology and Imaging Sciences, National Institutes of Health, Bethesda, Maryland, USA. 3. The Orthopaedic Center, A Division of CAO, Rockville, Maryland, USA.
Abstract
BACKGROUND: The tibial tubercle to trochlear groove (TT-TG) distance is used for screening patients with a variety of patellofemoral joint disorders to determine who may benefit from patellar medialization using a tibial tubercle osteotomy. Clinically, the TT-TG distance is predominately based on static imaging with the knee in full extension; however, the predictive ability of this measure for dynamic patellar tracking patterns is unknown. PURPOSE: To determine whether the static TT-TG distance can predict dynamic lateral displacement of the patella. STUDY DESIGN: Cohort study (Diagnosis); Level of evidence, 2. METHODS: The static TT-TG distance was measured at full extension for 70 skeletally mature subjects with (n = 32) and without (n = 38) patellofemoral pain. The dynamic patellar tracking patterns were assessed from approximately 45° to 0° of knee flexion by use of dynamic cine-phase contrast magnetic resonance imaging. For each subject, the value of dynamic lateral tracking corresponding to the exact knee angle measured in the static images for that subject was identified. Linear regression analysis determined the predictive ability of static TT-TG distance for dynamic patellar lateral displacement for each cohort. RESULTS: The static TT-TG distance measured with the knee in full extension cannot accurately predict dynamic lateral displacement of the patella. There was weak predictive ability among subjects with patellofemoral pain ( r2 = 0.18, P = .02) and no predictive capability among controls. Among subjects with patellofemoral pain and static TT-TG distances 15 mm or more, 8 of 13 subjects (62%) demonstrated neutral or medial patellar tracking patterns. CONCLUSION: The static TT-TG distance cannot accurately predict dynamic lateral displacement of the patella. A large percentage of patients with patellofemoral pain and pathologically large TT-TG distances may have neutral to medial maltracking patterns.
BACKGROUND: The tibial tubercle to trochlear groove (TT-TG) distance is used for screening patients with a variety of patellofemoral joint disorders to determine who may benefit from patellar medialization using a tibial tubercle osteotomy. Clinically, the TT-TG distance is predominately based on static imaging with the knee in full extension; however, the predictive ability of this measure for dynamic patellar tracking patterns is unknown. PURPOSE: To determine whether the static TT-TG distance can predict dynamic lateral displacement of the patella. STUDY DESIGN: Cohort study (Diagnosis); Level of evidence, 2. METHODS: The static TT-TG distance was measured at full extension for 70 skeletally mature subjects with (n = 32) and without (n = 38) patellofemoral pain. The dynamic patellar tracking patterns were assessed from approximately 45° to 0° of knee flexion by use of dynamic cine-phase contrast magnetic resonance imaging. For each subject, the value of dynamic lateral tracking corresponding to the exact knee angle measured in the static images for that subject was identified. Linear regression analysis determined the predictive ability of static TT-TG distance for dynamic patellar lateral displacement for each cohort. RESULTS: The static TT-TG distance measured with the knee in full extension cannot accurately predict dynamic lateral displacement of the patella. There was weak predictive ability among subjects with patellofemoral pain ( r2 = 0.18, P = .02) and no predictive capability among controls. Among subjects with patellofemoral pain and static TT-TG distances 15 mm or more, 8 of 13 subjects (62%) demonstrated neutral or medial patellar tracking patterns. CONCLUSION: The static TT-TG distance cannot accurately predict dynamic lateral displacement of the patella. A large percentage of patients with patellofemoral pain and pathologically large TT-TG distances may have neutral to medial maltracking patterns.
Entities:
Keywords:
biomechanics; kinesiology; knee; magnetic resonance imaging; osteotomy; patella
Authors: Peter G Gerbino; David Zurakowski; Ricardo Soto; Elizabeth Griffin; Thomas S Reig; Lyle J Micheli Journal: J Pediatr Orthop Date: 2008 Jan-Feb Impact factor: 2.324
Authors: Frances T Sheehan; Aditya Derasari; Kenneth M Fine; Timothy J Brindle; Katharine E Alter Journal: Clin Orthop Relat Res Date: 2009-05-09 Impact factor: 4.176
Authors: Giampietro L Vairo; Joaquin Moya-Angeler; Michael A Siorta; Ashley H Anderson; Paul S Sherbondy Journal: Clin Orthop Relat Res Date: 2019-06 Impact factor: 4.176
Authors: Jarred M Kaiser; Michael F Vignos; Richard Kijowski; Geoffrey Baer; Darryl G Thelen Journal: Am J Sports Med Date: 2017-09-13 Impact factor: 6.202
Authors: Alex E White; Peters T Otlans; Dylan P Horan; Daniel B Calem; William D Emper; Kevin B Freedman; Fotios P Tjoumakaris Journal: Orthop J Sports Med Date: 2021-05-20
Authors: Sergio Barroso Rosa; Peter Mc Ewen; Kenji Doma; Juan Francisco Loro Ferrer; Andrea Grant Journal: Orthop Surg Date: 2019-12-02 Impact factor: 2.071