This clinical photograph set demonstrates the 'Prone Lying Active Knee Flexion' test, a movement control assessment for the lumbar spine and pelvis. Image A (left) displays the correct performance of the test: the subject is prone, actively flexing the knee toward 90 degrees while maintaining a neutral, stable lower back and pelvis without rotational compensation. Image B (right) illustrates a positive/incorrect finding: as the knee flexes, there is observable anterior tilting or rotation of the pelvis and lumbar spine, indicating poor segmental stabilization and movement dysfunction. This diagnostic protocol, based on Sahrmann and O'Sullivan criteria, is utilized in physical therapy and orthopedics to evaluate rotational control of the lumbopelvic region. The comparison highlights how regional interdependence between the hip and lumbar spine can manifest as compensatory movement patterns in patients with low back pain or instability.

Diagnostic CT scans of the human pelvis and lumbar spine demonstrating lumbopelvic parameters. The image consists of four panels: three sagittal views (1a, 1b, 1c) and one axial view (2). Panel 1a illustrates the measurement of the Pelvic Radius (PR), shown as a green line connecting the posterior-superior corner of the S1 vertebra to the center point between the femoral heads. Panel 1b displays the Pelvic Incidence (PI) angle, formed between a line perpendicular to the sacral plateau and a line connecting the center of the sacral plateau to the midpoint of the femoral heads. Panel 1c shows the Sacral Table Angle (STA), defined by the angle between the posterior wall of the sacrum and the sacral plateau. Panel 2 provides an axial cross-section at the level of the hip joints, showing bilateral femoral heads within the acetabula, with horizontal and vertical reference lines intersecting the centers of rotation to aid spatial orientation and triangulation. These measurements are essential in orthopedic and radiological assessments of spinal sagittal balance and pelvic morphology.

This clinical photograph displays a side-by-side comparison (A and B) of a Prone Lying Active Knee Flexion test, used to assess motor control of the lumbar spine and pelvis. The subject is positioned prone on an examination table. In Image A (Correct), the subject performs active knee flexion to 90 degrees while maintaining a neutral lumbar spine and stable pelvic alignment, with the torso remaining in contact with the bed. In Image B (Incorrect), the same movement results in a compensatory lumbo-pelvic dysfunction; as the knee flexes, the lower back exhibits an anterior pelvic tilt and lumbar extension (arching), creating visible space between the lower back and the table surface. This visual demonstrates movement impairment where the subject fails to dissociate knee flexion from spinal movement, suggesting a lack of lumbopelvic stability or 'extension control' dysfunction in the context of physical therapy and orthopedic assessment.

This composite procedural image details the instrumentation setup for 3D motion analysis of the pelvis and lumbar spine. Panel A shows two inertial sensors: the upper sensor is attached to a protective foam layer, and the lower sensor is fixed to an angulated plastic plate designed to avoid interference. Panel B displays the sensors applied to a subject in a control condition. The upper sensor is secured with medical adhesive tape over the thoracic spine through an aperture in the shirt. The lower sensor is positioned over the sacrum, stabilized by an elastic band and adhesive, and extends beneath the waistline. Panel C illustrates the experimental condition where a lumbar belt is worn. The belt is applied over the lower sensor's stabilization plate and elastic band, demonstrating how the specialized mounting allows for continuous pelvic monitoring without physical interference from the support garment. This setup is utilized in biomechanical research to evaluate the effects of lumbar belts on lumbopelvic rhythm and spinal range of motion.

Anatomical biomechanics diagram illustrating the three planes of motion—pitch, roll, and yaw—applied to the cervical and lumbar spine using 3D musculoskeletal skeletal models. The top row focuses on the cervical spine and head: 'Pitch' shows flexion (forward tilting of the skull), 'Roll' shows lateral flexion (side tilting), and 'Yaw' shows axial rotation (horizontal turning of the head). The bottom row displays these movements in the lumbar spine and full body: 'Pitch' depicts trunk flexion at the waist, 'Roll' shows lateral trunk bending, and 'Yaw' illustrates axial rotation of the torso relative to the pelvis with arms extended. The diagram serves as an educational tool for understanding spinal kinematics, range of motion, and orientation during movement analysis or clinical extrication studies. Labels indicate the specific anatomical region (Cervical vs. Lumbar) and the rotational axis (Pitch/Roll/Yaw), utilizing precise biomechanical terminology to define multi-planar spinal movement.

This clinical photograph demonstrates the assessment of lumbar flexion range of motion using the Modified-Modified Schober’s Test (MMST). The patient is positioned in active forward trunk flexion, while the clinician, standing to the side and slightly behind, uses a pink flexible measuring tape to determine the distance between two pre-marked anatomical landmarks on the lumbar spine. These landmarks typically include a point level with the inferior margins of the posterior superior iliac spines (PSIS) and a second point marked 15 cm superiorly along the midline. The image captures the dynamic measurement phase where the expansion of the skin over the lumbar vertebrae is quantified. The setting is a physiotherapy clinic, indicated by a treatment table with a red cover, a pillow, and therapeutic modalities like a pressure biofeedback unit or electrical stimulation machine in the background. This procedure is a standard clinical method for objectively evaluating spinal mobility and monitoring progress in patients with low back pain or movement control impairments.

This set of clinical photographs demonstrates the application of wearable sensors for kinematic assessment of the lumbar spine. Image (a) shows the posterior view of a participant in a neutral standing position with two sensors vertically aligned on the lower back: a green twin-axis Biometrics electrogoniometer spanning L1–L5 and a shorter Plastic Optical Fiber (POF) sensor positioned at the L3–L4 level. Images (b) through (e) illustrate the participant performing fundamental spinal movements for range of motion (ROM) validation: (b) lumbar flexion (forward bending), (c) lumbar extension (backward bending), (d) right lateral flexion, and (e) left lateral flexion. The sensors are firmly adhered to the skin, conforming to the spinal curvature during movement to capture changes in sagittal and frontal plane angles. This setup is typical in physical therapy research and biomechanics for evaluating spinal mobility, postural control, and the accuracy of novel wearable diagnostic technologies against established goniometric standards.