Kneeling-induced calf ischemia: a pilot study in apparently healthy European young subjects

• Published in: European journal of applied physiology Vol. 121; no. 11; pp. 3031 - 3040
• Main Authors: Ramondou, Pierre, Hersant, Jeanne, Bernardeau, Elise, Moumneh, Thomas, Feuilloy, Mathieu, Henni, Samir, Abraham, Pierre
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.11.2021; Springer Nature B.V; Springer Verlag
• Subjects: Adult; Biomedical and Life Sciences; Biomedicine; Blood pressure; Body weight; Children; Engineering Sciences; Female; France; Healthy Volunteers; Human Physiology; Humans; Ischemia; Ischemia - physiopathology; Knee; Leg - blood supply; Male; Occupational Medicine/Industrial Medicine; Original Article; Perfusion; Pilot Projects; Posture - physiology; Prospective Studies; Sports Medicine; France; Lower limb; Occupational diseases; Transcutaneous oximetry; Positional disease; Oxygen pressure; Sports
• ISSN: 1439-6319; 1439-6327; 1439-6327
• DOI: 10.1007/s00421-021-04764-8

Purpose Many tasks, sports or leisure activities require maximal knee flexion. We hypothesized that this position could result in reduced calf perfusion, in young European subjects. Methods We quantified calf ischemia resulting from the knee flexion with transcutaneous oxygen pressure (TcpO2) sensors by assessing the decrease from rest of TcpO2 (DROP) defined as limb changes minus chest changes. A minimal DROP (DROPm) <−15 mmHg defines the presence of ischemia. From the crawling position, participants kneeled for 3 min while bending as in prostration/prayer position (P). Thirty-five participants repeated this maneuver a second time, while 7 participants were also required to sit on their heels with the torso in the vertical position to attain knee flexion without significant groin flexion (S). Result In 41 healthy young volunteers (30 males), 25 [20–31] years old, 37 patients showed a DROPm < −15 mmHg from “R” to “P” in one ( n  = 4) or both ( n  = 33) calves (90.2%; 95% CI 76.9–97.3). After backward regression of the DROPm, there was no significant association with side, body weight of systolic blood pressure. However, age was strongly associated with DROPm (OR 5.34 [2.45–8.69]) so that DROPm was significantly higher in older, with a correlation ρ = 0.31 ( p  = 0.003). Conclusion Kneeling dramatically reduces calf perfusion, likely through popliteal artery kinking, possibly through muscle crushing. Eastern lifestyle includes routine flexed position since childhood. Whether or not such a chronic training reduces the risk of kneeling-induced ischemia in adults is unknown to date. Graphic abstract