TY - JOUR
T1 - Accuracy and Reliability of the Visual Assessment of Patellar Tracking
AU - Best, Matthew J.
AU - Tanaka, Miho J.
AU - Demehri, Shadpour
AU - Cosgarea, Andrew J.
N1 - Funding Information:
Using visual assessment alone, surgeons correctly identified patellar maltracking in approximately two-thirds of videos and correctly graded patellar maltracking in half. Inter- and intraobserver reliability were inadequate to support the use of visual assessment alone for detecting the presence or grade of patellar maltracking. Surgeon experience did not correlate with ability to identify the presence or grade of patellar maltracking. dynamic imaging interobserver reliability J-sign patellar instability patellar maltracking edited-state corrected-proof typesetter ts1 The authors thank Lynne Jones, PhD, and the Center for Biostatistics, Epidemiology, and Data Management for assistance with data analysis. Submitted April 8, 2019; accepted October 23, 2019. Presented at the interim meeting of the AOSSM, Las Vegas, Nevada, March 2019. One or more of the authors has declared the following potential conflict of interest or source of funding: A.J.C. has received education payments from Supreme Orthopedic Systems. M.J.T. has received a grant from DJO and education payments from Supreme Orthopedic Systems. S.D. has received grants from GE Healthcare and Aastrom Biosciences, consulting fees from Pfizer, and honoraria from Vericel Corp. M.J.B. has received education payments from Supreme Orthopedic Systems. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto. A Video Supplement for this article is available online.
PY - 2020/2/1
Y1 - 2020/2/1
N2 - Background: Abnormal patellar tracking is described as a “J-sign” when the patella exhibits excessive lateral displacement during active knee extension. Purpose: To determine (1) the accuracy and reliability of the visual assessment of patellar tracking when viewed by surgeons with patellofemoral expertise and (2) whether surgeon experience (in years) correlates with the ability to accurately identify the presence and severity of patellar maltracking. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: Using a web-based assessment, 32 orthopaedic surgeon members of the International Patellofemoral Study Group determined the presence or absence of maltracking (≥2 quadrants of lateral translation) in 10 single-knee videos of patients with patellar instability during active knee extension (qualitative analysis). Surgeons then graded patellar tracking in 20 single-knee videos as follows: 0 (<1 patellar quadrant of lateral translation), 1 (1 to <2 quadrants), 2 (2 to <3 quadrants), or 3 (≥3 quadrants) (quantitative analysis). Responses were compared with a previously described grading system using patellar bisect offset measured with 4-dimensional computed tomography. We evaluated the association between number of years of surgeon experience and the ability to correctly identify and grade patellar tracking. A total of 22 surgeons repeated the survey 3 months later, and their answers were matched to the first survey, allowing for assessment of intraobserver reliability. Results: In the qualitative analysis, surgeons correctly identified videos as showing patellar maltracking 68% of the time (κ = 0.45). In the quantitative analysis, 53%, 51%, 48%, and 68% of surgeons correctly identified maltracking of grades 3, 2, 1, and 0, respectively (κ = 0.42). Surgeon experience did not correlate with ability to identify the presence (P =.59) or grade (P =.35) of patellar maltracking. Respondent answers from the second survey demonstrated inadequate intraobserver reliability (κ = 0.48). Conclusion: Using visual assessment alone, surgeons correctly identified patellar maltracking in approximately two-thirds of videos and correctly graded patellar maltracking in half. Inter- and intraobserver reliability were inadequate to support the use of visual assessment alone for detecting the presence or grade of patellar maltracking. Surgeon experience did not correlate with ability to identify the presence or grade of patellar maltracking.
AB - Background: Abnormal patellar tracking is described as a “J-sign” when the patella exhibits excessive lateral displacement during active knee extension. Purpose: To determine (1) the accuracy and reliability of the visual assessment of patellar tracking when viewed by surgeons with patellofemoral expertise and (2) whether surgeon experience (in years) correlates with the ability to accurately identify the presence and severity of patellar maltracking. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: Using a web-based assessment, 32 orthopaedic surgeon members of the International Patellofemoral Study Group determined the presence or absence of maltracking (≥2 quadrants of lateral translation) in 10 single-knee videos of patients with patellar instability during active knee extension (qualitative analysis). Surgeons then graded patellar tracking in 20 single-knee videos as follows: 0 (<1 patellar quadrant of lateral translation), 1 (1 to <2 quadrants), 2 (2 to <3 quadrants), or 3 (≥3 quadrants) (quantitative analysis). Responses were compared with a previously described grading system using patellar bisect offset measured with 4-dimensional computed tomography. We evaluated the association between number of years of surgeon experience and the ability to correctly identify and grade patellar tracking. A total of 22 surgeons repeated the survey 3 months later, and their answers were matched to the first survey, allowing for assessment of intraobserver reliability. Results: In the qualitative analysis, surgeons correctly identified videos as showing patellar maltracking 68% of the time (κ = 0.45). In the quantitative analysis, 53%, 51%, 48%, and 68% of surgeons correctly identified maltracking of grades 3, 2, 1, and 0, respectively (κ = 0.42). Surgeon experience did not correlate with ability to identify the presence (P =.59) or grade (P =.35) of patellar maltracking. Respondent answers from the second survey demonstrated inadequate intraobserver reliability (κ = 0.48). Conclusion: Using visual assessment alone, surgeons correctly identified patellar maltracking in approximately two-thirds of videos and correctly graded patellar maltracking in half. Inter- and intraobserver reliability were inadequate to support the use of visual assessment alone for detecting the presence or grade of patellar maltracking. Surgeon experience did not correlate with ability to identify the presence or grade of patellar maltracking.
KW - J-sign
KW - dynamic imaging
KW - interobserver reliability
KW - patellar instability
KW - patellar maltracking
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U2 - 10.1177/0363546519895246
DO - 10.1177/0363546519895246
M3 - Article
C2 - 31913663
AN - SCOPUS:85077612485
VL - 48
SP - 370
EP - 375
JO - American Journal of Sports Medicine
JF - American Journal of Sports Medicine
SN - 0363-5465
IS - 2
ER -