Seating & Wheelchair Angles Pelvic & Spinal Postures POTENTIAL CLINICAL CAUSES POTENTIAL TECHNICAL (EQUIPMENT) CAUSES Low or absent tone in the trunk muscles/low tone/muscle control in pelvis or trunk Seat depth too long Abnormal (high, low, or fluctuating) tone in trunk and/or lower extremities Footplate position relative to knee does not accommodate tight PELVIS + SAGITTAL Pathological reflexes in lower extremities or trunk/abnormal reflexes in hamstring trunk/lower extremities Front end angle/hanger angle doesn’t accommodate hamstring PELVIC ANGLE range Limited hip flexion Footplates too high (thighs not loaded sufficiently) (Posterior Pelvic Tilt) Decreased lordosis Footplates too low (feet not loaded sufficiently) Decreased pelvic/lumbar spine range of motion Lack of posterior pelvis/sacral support Decreased hamstring ROM Back support too upright Seat-to-floor height too high for foot propulsion Armrests too low – SAGITTAL EXTREMITIES & LOWER Increased lumbar lordosis PELVIC ANGLE Tightened paraspinals Anterior femoral angle (knees lower than hips) (Anterior Pelvic Tilt) Weakened abdominals Excessive lumbar contour Tight quadriceps Trunk not supported Tight hip flexors Back support too upright Obesity Scoliosis Poor base of support - i.e. sling upholstery Abnormal reflexes in trunk or lower limbs Footplates, position and/or seat-to-back angle or Asymmetrical muscle tone (trunk and/or lower front end angle may not match client's FRONTAL extremities) available range of motion PELVIC ANGLE Asymmetrical trunk muscle strength Seat shape does not support trochanters Asymmetrical soft tissue or muscle mass Wheelchair too wide (Obliquity) Asymmetrical pelvic/femur bone structure Seat and/or back does not provide enough Asymmetrical hip flexion range of motion lateral pelvic support Limited hip abduction and/or adduction Joystick and/or wheel location inappropriate Limited hip internal or external rotation Armrests too low (upper extremities not supported) Scoliosis or roto scoliosis TRANSVERSE Asymmetrical hip flexion Asymmetrical muscle tone (trunk and/or lower Trunk not fully supported PELVIC ANGLE leg length discrepancy) Lack of posterior pelvis/sacral support (Rotation) Posterior dislocated or subluxed hip Seat and or/or backrest contours too narrow Limited hip abduction and/or adduction range Seat-to-floor height too high for foot of motion propulsion Asymmetrical muscle mass in the posterior Wheel set up incorrect for hand propulsion pelvis Unilateral foot propeller (extremities) Low/absent muscle tone in the trunk muscles Seat-to-back angle too closed Compensation for posterior pelvic tilt Back support too low Clinical Assessment Goals: SAGITTAL Diminished head control Arm support too low Postural deterioration over time Back does not match shape of posterior trunk Identify posture/orthopedic asymmetries STERNAL ANGLE Extreme hyper mobility Head support mounted too far forward W at each body segment. Hyper extended cervical spine or too low Is asymmetry reducible or non-reducible? (Upper Diminished disc space in upper thoracic spine Wheel set up incorrect for hand propulsion Measure angles in frontal, sagittal, and transverse plane. Kyphosis) Absolute angles measure angles between a line connecting 2 points of reference on Back does not match shape of posterior trunk PELVIS the body and a neutral/plumb line. Low tone/poor muscle control in pelvis or Seat-to-back angle too open or closed Angles which have moved clockwise trunk Lack of adequate posterior pelvis/sacral from neutral axis are (-). Compensation for posterior pelvic tilt support/back does not support posterior pelvis Angles which have moved counter- SAGITTAL Structural spinal deformity Back support too vertical clockwise from neutral axis are (+). Diminished head control Back support too low TRUNK ANGLE Compensation for visual impairment Head support mounted too far forward or too low (Kyphosis) Arm supports too low & SPINE Low or absent muscle tone in the trunk muscles Anterior femoral angle (knees lower than hips) Tightened paraspinals Back too vertical Hypermobility of lumbar spine Excessive lumbar contour Compensation for anterior tilted pelvis Back does not match shape of posterior trunk Compensation for lumbar instability Posterior pelvic support too high SAGITTALSSAAGIT ABDOMINAL Obesity Back support too low ANGLEAANGLE (Lordosis) Fixed structural deformity Orientation in space not optimal (system too upright) Back does not match shape of posterior trunk Compensation for pelvic obliquity and/or pelvic rotation Back does not support posterior pelvis SCOLIOSIS Asymmetrical muscle tone or strength in the trunk muscles Back does not provide enough lateral support Decreased trunk balance Wheelchair does not provide solid base (sling upholstery) Structural spinal deformity Seat cushion does not provide pelvic stability Asymmetrical upper extremity strength during manual Upper extremity support is too low, too high, or too wide wheelchair propulsion Joystick or wheel location inappropriate Inability to hold the head in midline 9 REFERENCES: Waugh, K. and Crane, B. (2013). A clinical application guide to standardized wheelchair seating measures of the body and seating support surfaces (rev. Ed.). Denver, CO. University of Colorado Denver. Available from: http://www.ucdenver.edu/academics/AssistiveTechnologyPartners/resources/WheelchairSeating/Pages/WheelchairGuideForm.aspx Waugh, K. and Crane, B. (2013). Glossary of wheelchair terms and definitions. Denver, CO. University of Colorado Denver. Available from: https://www.ncart.us/uploads/userfiles/files/glossary-of-wheelchair-terms.pdf Zwick, D. (2014). How Posture Goes Wrong: Body Shape Distortion in Cerebral Palsy. Available from: https://www.omicsonline.org/open-access/how-posture-goes-wrong-body-shape-distortion-in-cerebral-palsy-2157-7595.1000e115.php?aid=25348 DISCLAIMER: FOR PROFESSIONAL USE ONLY. THIS DOCUMENT (AND THE WEBSITE REFERENCED HEREIN) DO NOT PROVIDE MEDICAL ADVICE. Sunrise Medical (US) LLC does not provide clinician services. The information contained on this document (and the website referenced herein), including, but not limited to, the text, graphics, images, and descriptions, are for informational purposes only and should be utilized as a general resource for clinicians and suppliers to then use clinical reasoning skills to determine optimal seating and mobility solutions for individual patients. No material on this document (or on the website) is intended to be used as (or a substitute for) professional medical advice, diagnosis or treatment. Clinicians should adhere to their professional medical training and their institution’s or practice’s recommended guidelines. Reliance on this document (and the information contained herein) is solely at your own risk. Sunrise Medical (US) LLC, Fresno, CA 93727 MK-129716 Rev.A ©05.2019 800.333.4000 www.SunriseMedical.com/EIM.