Advances in time-frequency analysis can provide new insights into the important, yet complex relationship between muscle activation (ie, electromyography [EMG]) and motion during dynamic tasks. We use wavelet coherence to compare a fundamental cyclical movement (lumbar spine flexion and extension) to the surface EMG linear envelope of 2 trunk muscles (lumbar erector spinae and internal oblique). Both muscles cohere to the spine kinematics at the main cyclic frequency, but lumbar erector spinae exhibits significantly greater coherence than internal oblique to kinematics at 0.25, 0.5, and 1.0 Hz. Coherence phase plots of the 2 muscles exhibit different characteristics. The lumbar erector spinae precedes trunk extension at 0.25 Hz, whereas internal oblique is in phase with spine kinematics. These differences may be due to their proposed contrasting functions as a primary spine mover (lumbar erector spinae) versus a spine stabilizer (internal oblique). We believe that this method will be useful in evaluating how a variety of factors (eg, pain, dysfunction, pathology, fatigue) affect the relationship between muscles’ motor inputs (ie, activation measured using EMG) and outputs (ie, the resulting joint motion patterns).
Dean C. Hay, Mark P. Wachowiak, and Ryan B. Graham
Kayla M. Fewster, Jackie D. Zehr, Chad E. Gooyers, Robert J. Parkinson, and Jack P. Callaghan
participants. 54 While no significant sex effects were observed across unsupported and supported impacts for lumbar spine kinematics, it is interesting to note that on average, for unsupported impacts, female participants experienced an approximate 6 degree average increase in peak lumbar spine flexion in
Brad Rutledge, Tamara Reid Bush, Joseph Vorro, Mingfei Li, Lisa DeStefano, Sherman Gorbis, Timothy Francisco, and Michael Seffinger
Most musculoskeletal disorders of the head and neck regions cannot be identified through imaging techniques; therefore clinician-conducted assessments (passive motions) are used to evaluate the functional ability of these regions. Although active motions do not require interaction with a clinician, these movements can also provide diagnostic indicators of dysfunction. The purpose of this research was to determine whether kinematic measures differed between active and passive movements of participants in symptomatic and asymptomatic groups. Data obtained on cervical lateral flexion range of motion (ROM), coupled axial rotation, and the angular velocity of lateral flexion were statistically analyzed and demonstrated differences between active and passive motions for symptomatic and asymptomatic subjects. Active motions had higher angular velocities (P < .001) and larger ROMs, with greater lateral flexions (P < .05). The asymptomatic group produced a larger average lateral flexion of 7.9° at an average angular velocity of 2 deg/s greater than the symptomatic group. Trends with regard to group assignment were the same for active and passive motions. This work demonstrates the potential for using kinematic measures of active and passive motions to develop an objective standard for diagnoses of cervical dysfunction and supports validity of the clinician-based analysis to distinguish between participant groups.
Fadi M. Al Zoubi and Richard A. Preuss
Measuring lumbar spine range of motion (ROM) using multiple movements is impractical for clinical research, because finding statistically significant effects requires a large proportion of subjects to present with the same impairment. The purpose of this study was to develop a single measure representing the total available lumbar ROM. Twenty participants with low back pain performed three series of eight lumbar spine movements, in each of two sessions. For each series, an ellipse and a cubic spline were fit to the end-range positions, measured based on the position of the twelfth thoracic vertebra in the transverse plane of the sacrum. The area of each shape provides a measure of the total available ROM, whereas their center reflects the movements’ symmetry. Using generalizability theory, the index of dependability for the area and anterior-posterior center position was found to be 0.90, but was slightly lower for the mediolateral center position. Slightly better values were achieved using the spline-fitting approach. Further analysis also indicated that excellent reliability, and acceptable minimal detectable change values, would be achieved with a single testing session. These data indicate that the proposed measure provides a reliable and easily interpretable measure of total lumbar spine ROM.
Mohammad Reza Pourahmadi, Ismail Ebrahimi Takamjani, Shapour Jaberzadeh, Javad Sarrafzadeh, Mohammad Ali Sanjari, Rasool Bagheri, and Morteza Taghipour
provides a noninvasive approach to measure dynamic movement of the spine during daily activities. It is also important to note that the difficulty in locating relevant anatomical landmarks to effectively define axial rotation in the transverse plane limits the analysis of lumbar spine kinematics to the
Lindsey Tulipani, Mark G. Boocock, Karen V. Lomond, Mahmoud El-Gohary, Duncan A. Reid, and Sharon M. Henry
Physical therapists evaluate patients’ movement patterns during functional tasks; yet, their ability to interpret these observations consistently and accurately is unclear. Physical therapists would benefit from a clinic-friendly method for accurately quantifying movement patterns during functional tasks. Inertial sensors, which are inexpensive, portable sensors capable of monitoring multiple body segments simultaneously, are a relatively new rehabilitation technology. We sought to validate an inertial sensor system by comparing lower limb and lumbar spine kinematic data collected simultaneously with a commercial inertial sensor system and a motion camera system while 10 subjects performed functional tasks. Mean and peak segment angular displacement data were calculated and compared between systems. Mean angular displacement root mean square error between the systems across all tasks and segments was <5°. Mean differences in peak displacements were generally acceptable (<5°) for the femur, tibia, and pelvis segments for all tasks; however, the inertial system overestimated lumbar flexion compared to the motion camera system. These data suggest that the inertial system is capable of measuring angular displacements within 5° of a system widely accepted for its accuracy. Standardization of sensor placement, better attachment methods, and improvement of inertial sensor algorithms will further increase the accuracy of the system.
Rumit S. Kakar, Seth Higgins, Joshua M. Tome, Natalie Knight, Zachary Finer, Zachary Doig, and Yumeng Li
observed during trunk extension. 3 , 5 Employees who work in industries that require excessive and prolonged flexion and extension of the trunk are at an increased risk of developing low back pain. 7 Analyzing spine kinematics can provide invaluable information on spine function, which can be used to
Kaitlin M. Gallagher, Anita N. Vasavada, Leah Fischer, and Ethan C. Douglas
-specific vertebral position and head and neck size on cervical spine musculoskeletal moments. 15 Our study confirmed this with significant associations of musculotendon lengths with cervical spine kinematics, sex, and height. Forty-six percent of images showed participants with flexion of the Skull-C1 joint. This
Hardeep Singh, Mark Lee, Matthew J. Solomito, Christian Merrill, and Carl Nissen
kinematic profiles of the lumbar spine were compared among the 3 study groups. The results indicated that the lumbar spine kinematic profile was conserved throughout the pitch cycle regardless of age (Figure 2 ). Lumbar extension increased between foot contact to approximately one-third of the pitch cycle
Rasool Bagheri, Ismail Ebrahimi Takamjani, Mohammad R. Pourahmadi, Elham Jannati, Sayyed H. Fazeli, Rozita Hedayati, and Mahmood Akbari
K , Portscher And N , Banzer W . Influences of nonspecific low back pain on three-dimensional lumbar spine kinematics in locomotion . Spine . 2001 ; 26 ( 17 ): 1910 – 1919 . doi:10.1097/00007632-200109010-00019 10.1097/00007632-200109010-00019 11568705 2. Steele J , Bruce-Low S