Near-Infrared Spectroscopy measurements are reliable for studying patellar bone hemodynamics and affected by venous occlusion, but not by skin compression

Martin J Ophey; Anne Westerweel; Maxime van Oort; Robert van den Berg; Gino M M J Kerkhoffs; Igor J R Tak

doi:10.1186/s40634-023-00709-6

Near-Infrared Spectroscopy measurements are reliable for studying patellar bone hemodynamics and affected by venous occlusion, but not by skin compression

J Exp Orthop. 2023 Nov 29;10(1):124. doi: 10.1186/s40634-023-00709-6.

Authors

Martin J Ophey^{1

2

3}, Anne Westerweel⁴, Maxime van Oort⁴, Robert van den Berg^{5

6

7}, Gino M M J Kerkhoffs^{8

9

10}, Igor J R Tak^{5

9

10

11}

Affiliations

¹ IJsveldFysio - Private Physical Therapy Clinic, Nijmegen, The Netherlands. m.j.ophey@amsterdamumc.nl.
² Department of Orthopaedic Surgery and Sports Medicine, Amsterdam UMC Location University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands. m.j.ophey@amsterdamumc.nl.
³ ESP Science and Education, Vienna, Austria. m.j.ophey@amsterdamumc.nl.
⁴ RU - Radboud University, Biomedical Sciences, Nijmegen, The Netherlands.
⁵ ESP Science and Education, Vienna, Austria.
⁶ FH Burgenland, Physical Therapy Department, University of Applied Science, Pinkafeld, Austria.
⁷ AIM - Austrian Institute of Management, Advanced Physiotherapy & Management, Eisenstadt, Austria.
⁸ Department of Orthopaedic Surgery and Sports Medicine, Amsterdam UMC Location University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
⁹ Amsterdam Collaboration On Health & Safety in Sports (ACHSS), IOC Research Center, Amsterdam, The Netherlands.
¹⁰ Academic Center for Evidence-Based Sports Medicine (ACES), Amsterdam, The Netherlands.
¹¹ Physiotherapy Utrecht Oost - Sports Rehabilitation and Manual Therapy, Utrecht, The Netherlands.

Abstract

Purpose: According to the homeostasis model, patellofemoral pain (PFP) results from disturbed homeostasis due to vascular insufficiency in the anterior knee. Near-Infrared Spectroscopy (NIRS) measures relative changes in concentrations (in µmol/cm²) of (de-)oxygenated hemoglobine (HHb and O₂Hb). The aims were to: 1) investigate the characteristics of the NIRS signal derived from the patella during experiments affecting hemodynamics in healthy controls, and 2) determine the test-retest reliability of NIRS in positions clinically relevant for PFP patients.

Methods: Two experiments were conducted on 10 healthy controls and analysed using Student's t-test. Reliability (ICC_2,1) was evaluated for two activities ('Prolonged Sitting' and 'Stair Descent') in five PFP patients and 15 healthy controls, performed twice within five days.

Results: The NIRS signal (HHb and O₂Hb) showed a statistically significant increase (p < .001 - .002) on all optodes (30, 35, 40 mm) during 'Venous Occlusion' (M = 1.0 - 2.0), while it showed no statistically significant change (p = .075 - .61) during 'Skin Compression' (M = -0.9 - 0.9) on the 30 and 35 mm optode. Reliability of NIRS (HHb and O₂Hb) ranged from moderate to almost perfect (ICC_2,1 = .47 - .95) on the 30 mm optode for 'Prolonged Sitting', and from moderate to substantial (ICC_2,1 = .50 - .68) on the 35 mm optode for 'Stair Descent'.

Conclusions: Patella NIRS measurements are affected by venous occlusion, but not by skin compression, and are sufficiently reliable as research application to compare real-time patellar bone hemodynamics. These insights may assist to improve effectiveness of evidence-based treatment strategies for PFP.

Trial registration: ISRCTN Trial Registration under number: 90377123.

Keywords: Near-Infrared Spectroscopy; Patellofemoral pain; Reliability.