Upper extremity hemodynamics and sensation with backpack loads.
Heavy backpacks are often used in extreme environments, for example by military during combat, therefore completion of tasks quickly and efficiently is of operational relevance. The purpose of this study was to quantify hemodynamic parameters (brachial artery Doppler and microvascular flow by photoplethysmography; tissue oxygenation by near-infrared spectroscopy; arterial oxygen saturation by pulse oximeter) and sensation in upper extremities and hands (Semmes-Weinstein monofilament test and 2-point discrimination test) while wearing a loaded backpack (12 kg) in healthy adults for 10 min. All values were compared to baseline before wearing a backpack. Moderate weight loaded backpack loads significantly decreased upper extremity sensation as well as all macrovascular and microvascular hemodynamic values. Decreased macrovascular and microvascular hemodynamics may produce neurological dysfunction and consequently, probably affect fine motor control of the hands.
Department of Orthopaedic Surgery, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea. Electronic address: drjacobkim@gmail.com.
Sae Hoon
SH
Kim
Department of Orthopaedic Surgery, University of California, UCSD Medical Center, San Diego, USA. Electronic address: tneuschwander@ucsd.edu.
Timothy B
TB
Neuschwander
Department of Health & Kinesiology, Texas A&M University, USA. Electronic address: dr.brandonmacias@gmail.com.
Brandon R
BR
Macias
Department of Orthopaedic Surgery, University of California, UCSD Medical Center, San Diego, USA. Electronic address: jr@ucsd.edu.
Larry
L
Bachman
Department of Orthopaedic Surgery, University of California, UCSD Medical Center, San Diego, USA. Electronic address: ahargens@ucsd.edu.
Alan R
AR
Hargens
D000293:Adolescent; D000328:Adult; D001132:Arm / Q000098:blood supply*; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D010092:Oximetry; D017156:Photoplethysmography; D012677:Sensation / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology*; D055815:Young Adult
Blood flow; Paresthesia; Upper extremity