Ana Leal1,2, Renato Andrade2,3,4, Betina B Hinckel5, Marc Tompkins6,7, Paulo Flores1, Filipe Silva1, João Espregueira-Mendes8,9,10,11, Elizabeth Arendt6,7. 1. Mechanical Engineering Department, CMEMS Center for MicroElectroMechanical Systems, University of Minho, Guimarães, Portugal. 2. Dom Henrique Research Centre, Porto, Portugal. 3. Clínica do Dragão, Espregueira-Mendes Sports Centre, FIFA Medical Centre of Excellence, Porto, Portugal. 4. Faculty of Sports, University of Porto, Porto, Portugal. 5. Brigham and Woman's Hospital, Harvard Medical School, Boston, MA, USA. 6. Department of Orthopaedic Surgery, University of Minnesota, Minneapolis, USA. 7. TRIA Orthopaedic Center, Bloomington, MN, USA. 8. Dom Henrique Research Centre, Porto, Portugal. espregueira@dhresearchcentre.com. 9. Clínica do Dragão, Espregueira-Mendes Sports Centre, FIFA Medical Centre of Excellence, Porto, Portugal. espregueira@dhresearchcentre.com. 10. ICVS/3B's, PT Government Associated Laboratory, Braga/Guimarães, Portugal. espregueira@dhresearchcentre.com. 11. School of Medicine, Minho University, Braga, Portugal. espregueira@dhresearchcentre.com.
Abstract
PURPOSE: To evaluate the reliability of an instrumented patellofemoral (PF) stress-testing-the Porto Patellofemoral Testing Device (PPTD)-and validate the instrumented assessment method comparing to manual physical examination. METHODS: Eight asymptomatic volunteers underwent bilateral PF-instrumented examination with the PPTD and magnetic resonance imaging (MRI) to assess intra-rater reliability of the instrumented assessment methodology. Six patients with unilateral PF instability underwent physical examination and PPTD concomitantly with MRI. Manual examination was performed by two blinded surgeons and compared with PPTD test. Ligament stiffness was calculated and compared between injured and non-injured lower limbs. RESULTS: PPTD showed a pre-determined and reproducible stress-force application with excellent intra-rater agreement (intra-class correlation coefficient 0.83-0.98). The manual exam was imprecise with variable examiner-dependent stress-force application. The PPTD resulted in greater lateral patellar translation (converted in quadrants) than manual exam for patients that have reached maximum translation force. Measurement of patellar position and displacement using PPTD was more accurate and precise than the visual estimation of translated quadrants by manual exam. Ligament stiffness curves showed no relevant changes in patellar displacement after 62 N. CONCLUSION: The PPTD instrumented stress-testing is a valid device to quantify PF position and displacement with high intra-rater reliability, showing more accuracy, more precision and less variability than physical examination. This device provides an accurate and objective measure to quantify the patellar movement which can augment the physical examination procedures and assist clinicians in the management of decision-making and in the assessment of post-treatment outcomes of PF pathological conditions.
PURPOSE: To evaluate the reliability of an instrumented patellofemoral (PF) stress-testing-the Porto Patellofemoral Testing Device (PPTD)-and validate the instrumented assessment method comparing to manual physical examination. METHODS: Eight asymptomatic volunteers underwent bilateral PF-instrumented examination with the PPTD and magnetic resonance imaging (MRI) to assess intra-rater reliability of the instrumented assessment methodology. Six patients with unilateral PF instability underwent physical examination and PPTD concomitantly with MRI. Manual examination was performed by two blinded surgeons and compared with PPTD test. Ligament stiffness was calculated and compared between injured and non-injured lower limbs. RESULTS: PPTD showed a pre-determined and reproducible stress-force application with excellent intra-rater agreement (intra-class correlation coefficient 0.83-0.98). The manual exam was imprecise with variable examiner-dependent stress-force application. The PPTD resulted in greater lateral patellar translation (converted in quadrants) than manual exam for patients that have reached maximum translation force. Measurement of patellar position and displacement using PPTD was more accurate and precise than the visual estimation of translated quadrants by manual exam. Ligament stiffness curves showed no relevant changes in patellar displacement after 62 N. CONCLUSION: The PPTD instrumented stress-testing is a valid device to quantify PF position and displacement with high intra-rater reliability, showing more accuracy, more precision and less variability than physical examination. This device provides an accurate and objective measure to quantify the patellar movement which can augment the physical examination procedures and assist clinicians in the management of decision-making and in the assessment of post-treatment outcomes of PF pathological conditions.
Entities:
Keywords:
Arthrometer; Laxity; Magnetic resonance imaging; Patellofemoral; Patellofemoral instability
Authors: Marc A Tompkins; Sara R Rohr; Julie Agel; Elizabeth A Arendt Journal: Knee Surg Sports Traumatol Arthrosc Date: 2017-02-28 Impact factor: 4.342
Authors: Renato Andrade; Rogério Pereira; Ana Leal; Bruno Pereira; João Paulo Vilas Boas; C Niek van Dijk; João Espregueira-Mendes Journal: Porto Biomed J Date: 2021-02-11