scholarly journals Six-Degrees-of-Freedom Cervical Spine Range of Motion During Dynamic Flexion-Extension After Single-Level Anterior Arthrodesis

2013 ◽  
Vol 95 (6) ◽  
pp. 497-506 ◽  
Author(s):  
William J. Anderst ◽  
Joon Y. Lee ◽  
William F. Donaldson ◽  
James D. Kang
Keyword(s):  
Cervical Spine ◽  
Range Of Motion ◽  
Degrees Of Freedom ◽  
Six Degrees Of Freedom ◽  
Single Level ◽  
Flexion Extension

scholarly journals Experimental Analysis of Fabricated Synthetic Midthoracic Paediatric Spine as Compared to the Porcine Spine Based on Range of Motion (ROM)

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Nor Amalina Muhayudin ◽  
Khairul Salleh Basaruddin ◽  
Ruslizam Daud ◽  
Fiona McEvoy ◽  
Tansey
Keyword(s):  
Range Of Motion ◽  
Degrees Of Freedom ◽  
Axial Rotation ◽  
Lateral Bending ◽  
Main Interest ◽  
Biological Specimen ◽  
Six Degrees Of Freedom ◽  
Elastic Zone ◽  
Flexion Extension ◽  
Biomechanical Tests

The present study is aimed at investigating the mechanical behaviour of fabricated synthetic midthoracic paediatric spine based on range of motion (ROM) as compared to porcine spine as the biological specimen. The main interest was to ensure that the fabricated synthetic model could mimic the biological specimen behaviour. The synthetic paediatric spine was designed as a 200% scaled-up model to fit into the Bionix Servohydraulic spine simulator. Biomechanical tests were conducted to measure the ROM and nonlinearity of sigmoidal curves at six degrees of freedom (DOF) with moments at ±4 Nm before the specimens failed. Results were compared with the porcine spine (biological specimen). The differences found between the lateral bending and axial rotation of synthetic paediatric spine as compared to the porcine spine were 18% and 3%, respectively, but was still within the range. Flexion extension of the synthetic spine is a bit stiff in comparison of porcine spine with 45% different. The ROM curves of the synthetic paediatric spine exhibited nonlinearities for all motions as the measurements of neutral zone (NZ) and elastic zone (EZ) stiffness were below “1.” Therefore, it showed that the proposed synthetic paediatric spine behaved similarly to the biological specimen, particularly on ROM.

scholarly journals Neck Braces and Driving Posture Affect Neck Mobility on Powered Two-Wheelers

2021 ◽  
Vol 33 (3) ◽  
pp. 337-345
Author(s):  
Brieg Lecoublet ◽  
Yvan Petit ◽  
Eric Wagnac ◽  
Dominic Boisclair ◽  
Pierre-Jean Arnoux
Keyword(s):  
Cervical Spine ◽  
Range Of Motion ◽  
Degrees Of Freedom ◽  
Traffic Accidents ◽  
Axial Rotation ◽  
Cervical Spine Injuries ◽  
Flexion Extension ◽  
Spine Injuries ◽  
Driving Posture ◽  
Neck Mobility

Cervical spine injuries are a major concern for motorcyclists in traffic accidents and racing competitions. Neck braces aim to prevent cervical spine injuries during accidents by reducing the neck range of motion, and keeping it under physiological limits. This work aims to evaluate the ability of neck braces to reduce neck mobility for two driving postures associated with PTW configurations. The neck mobility of twelve volunteer subjects testing four neck braces on two powered two-wheelers (scooter and racing motorbike) is measured using an optoelectronic motion capture system. With the tested neck braces worn, neck mobility is significantly reduced as compared to the physiological range of motion in all degrees of freedom. However, only flexion/extension is reduced by all neck braces tested. This suggests that these brace designs do not provide protection against all the cervical spine loading directions that may occur in a trauma. Furthermore, specific type of each powered two-wheeler considered significantly affects the neck mobility in axial rotation, as well as the postero-anterior and caudo-cranial translations, thus underscoring the need to consider the driving posture when evaluating neck brace devices.

scholarly journals Biomechanical Analysis of an Anterior Cervical Discectomy and Fusion Pseudarthrosis Model Revised With Machined Interfacet Allograft Spacers

2019 ◽  
Vol 10 (8) ◽  
pp. 973-981
Author(s):  
Raymond J. Hah ◽  
Ram Alluri ◽  
Paul A. Anderson
Keyword(s):  
Range Of Motion ◽  
Study Design ◽  
Axial Rotation ◽  
Biomechanical Analysis ◽  
Anterior Cervical Discectomy ◽  
Lateral Bending ◽  
Cervical Discectomy ◽  
Single Level ◽  
Flexion Extension ◽  
Potential Applications

Study Design: Biomechanics study. Objectives: To evaluate the biomechanical advantage of interfacet allograft spacers in an unstable single-level and 2-level anterior cervical discectomy and fusion (ACDF) pseudoarthrosis model. Methods: Nine single-level and 8 two-level ACDF constructs were tested. Range of motion in flexion-extension (FE), lateral bending (LB), and axial rotation (AR) at 1.5 N m were collected in 4 testing configurations: (1) intact spine, (2) ACDF with interbody graft and plate/screw, (3) ACDF with interbody graft and plate/loosened screws (loose condition), and (4) ACDF with interbody graft and plate/loosened screws supplemented with interfacet allograft spacers (rescue condition). Results: All fixation configurations resulted in statistically significant decreases in range of motion in all bending planes compared with the intact spine ( P < .05). One Level. Performing ACDF with interbody graft and plate on the intact spine reduced FE, LB, and AR 60.0%, 64.9%, and 72.9%, respectively. Loosening the ACDF screws decreased these reductions to 40.9%, 44.6%, and 52.1%. The addition of interfacet allograft spacers to the loose condition increased these reductions to 74.0%, 84.1%, and 82.1%. Two Level. Performing ACDF with interbody graft and plate on the intact spine reduced FE, LB, and AR 72.0%, 71.1%, and 71.2%, respectively. Loosening the ACDF screws decreased these reductions to 55.4%, 55.3%, and 51.3%. The addition of interfacet allograft spacers to the loose condition significantly increased these reductions to 82.6%, 91.2%, and 89.3% ( P < .05). Conclusions: Supplementation of a loose ACDF construct (pseudarthrosis model) with interfacet allograft spacers significantly increases stability and has potential applications in treating cervical pseudarthrosis.

Cervical Spine Movement Sequencing During Flexion-Extension

2011 ◽  
Author(s):  
William J. Anderst ◽  
Michelle Schafman ◽  
William F. Donaldson ◽  
Joon Y. Lee ◽  
James D. Kang
Keyword(s):  
Cervical Spine ◽  
Range Of Motion ◽  
Daily Living ◽  
X Rays ◽  
Clinical Tool ◽  
Normal Range ◽  
Kinematic Data ◽  
Flexion Extension ◽  
Functional Movements ◽  
Spine Movement

Static flexion-extension x-rays are the most common clinical tool used to assess abnormal motion of the cervical spine. Despite their widespread use (over 168,000 cases per year), the clinical efficacy of flexion-extension radiographs of the cervical spine has yet to be proven1. Limitations of static flexion-extension x-rays include data collection during static positions that may not accurately represent dynamic behavior, and the fact that data is collected at end range of motion positions, not in more frequently encountered mid-range positions. Consequently, static x-rays may not reveal movement abnormalities that occur during activities of daily living and lead to pain and degeneration. Therefore, it may be advantageous to analyze cervical spine kinematic data collected during dynamic, functional movements performed through an entire range of motion (not just the endpoints). Furthermore, the literature confirms there is substantial variability in “normal” range of motion and translation during flexion-extension1, making it difficult to reliably identify abnormal motion. Therefore, it may also be beneficial to evaluate alternative motion parameters that may reliably identify abnormal motion.

scholarly journals Comparison of the efficacy of three cervical collars in restricting cervical range of motion: A randomized study

2018 ◽  
Vol 27 (1) ◽  
pp. 24-29 ◽  
Author(s):  
Jae Guk Kim ◽  
Sung Hwan Bang ◽  
Gu Hyun Kang ◽  
Yong Soo Jang ◽  
Wonhee Kim ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Range Of Motion ◽  
Cervical Spine Injury ◽  
Axial Rotation ◽  
The Other ◽  
Spine Injury ◽  
Cervical Range Of Motion ◽  
Flexion Extension ◽  
Cervical Immobilization ◽  
The Difference

Background: The cervical collar has been used as a common device for the initial stabilization of the cervical spine. Although many cervical collars are commercially available, there is no consensus on which offers the greatest protection, with studies showing considerable variations in their ability to restrict cervical range of motion. The use of the XCollar (Emegear, Carpinteria, CA) has been known to decrease the risk of spinal cord injury by minimizing potential cervical spinal distraction. We compared XCollar with two other cervical collars commonly used for adult patients with cervical spine injury to evaluate the difference in effectiveness between the three cervical collars to restrict cervical range of motion. Objectives: This study aimed to evaluate the difference between the three cervical collars in their ability to restrict cervical range of motion. Method: A total of 30 healthy university students aged 21–25 years participated in this study. Participants with any cervical disease and symptoms were excluded. Three cervical collars were tested: Philadelphia® Collar, Stifneck® Select™ Collar, and XCollar. A digital camera and an image-analysis technique were used to evaluate cervical range of motion during flexion, extension, bilateral bending and bilateral axial rotation. Cervical range of motion was evaluated in both the unbraced and braced condition. Results: XCollar permitted less than a mean of 10° of movement during flexion, extension, bilateral bending and bilateral axial rotation. This was less than the movement permitted by the other two cervical collars. Conclusion: XCollar presented superior cervical immobilization compared to the other two commonly used cervical collars in this study. Thus, when cervical collar is considered for an adult patient with cervical spine injury, XCollar might be one of the considerate options as a cervical immobilization device.

Validation of a Novel 3D-Printed Instrumented Spatial Linkage That Measures Changes in the Rotational Axes of the Tibiofemoral Joint

2013 ◽  
Author(s):  
Daniel P. Bonny ◽  
S. M. Howell ◽  
M. L. Hull
Keyword(s):  
Degrees Of Freedom ◽  
Rigid Bodies ◽  
Anatomic Landmarks ◽  
Tibiofemoral Joint ◽  
Six Degrees Of Freedom ◽  
Revolute Joints ◽  
Flexion Extension ◽  
3D Printed ◽  
Total Knee ◽  
Position And Orientation

The two kinematic axes of the tibiofemoral joint, the flexion-extension (F-E) and longitudinal rotation (LR) axes [1], are unrelated to the anatomic landmarks often used to align prostheses during total knee arthroplasty (TKA) [1, 2]. As a result, conventional TKA changes the position and orientation of the joint line, thus changing the position and orientation of the F-E and LR axes and consequently the kinematics of the knee. However, the extent to which TKA changes these axes is unknown. An instrument that can measure the locations of and any changes to these axes is an instrumented spatial linkage (ISL), a series of six instrumented revolute joints that can measure the six degrees of freedom of motion (DOF) between two rigid bodies without constraining motion. Previously, we computationally determined how best to design and use an ISL such that rotational and translational errors in locating the F-E and LR axes were minimized [3]. However, this ISL was not constructed and therefore its ability to measure changes in the axes has not been validated. Therefore the objective was to construct the ISL and quantify the errors in measuring changes in position and orientation of the F-E axis.

scholarly journals Pseudarthrosis rate following anterior cervical discectomy with fusion using an allograft cellular bone matrix: a multi-institutional analysis

2021 ◽  
Vol 50 (6) ◽  
pp. E6
Author(s):  
Stephen M. Bergin ◽  
Timothy Y. Wang ◽  
Christine Park ◽  
Shashank Rajkumar ◽  
C. Rory Goodwin ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Bone Growth ◽  
Bone Matrix ◽  
Anterior Cervical Discectomy ◽  
Cervical Discectomy ◽  
Cervical Spine Surgery ◽  
Single Level ◽  
Flexion Extension ◽  
Index Level ◽  
Instrumentation Failure

OBJECTIVE The use of osteobiologics, engineered materials designed to promote bone healing by enhancing bone growth, is becoming increasingly common for spinal fusion procedures, but the efficacy of some of these products is unclear. The authors performed a retrospective, multi-institutional study to investigate the clinical and radiographic characteristics of patients undergoing single-level anterior cervical discectomy with fusion performed using the osteobiologic agent Osteocel, an allograft mesenchymal stem cell matrix. METHODS The medical records across 3 medical centers and 12 spine surgeons were retrospectively queried for patients undergoing single-level anterior cervical discectomy and fusion (ACDF) with the use of Osteocel. Pseudarthrosis was determined based on CT or radiographic imaging of the cervical spine. Patients were determined to have radiographic pseudarthrosis if they met any of the following criteria: 1) lack of bridging bone on CT obtained > 300 days postoperatively, 2) evidence of instrumentation failure, or 3) motion across the index level as seen on flexion-extension cervical spine radiographs. Univariate and multivariate analyses were then performed to identify independent preoperative or perioperative predictors of pseudarthrosis in this population. RESULTS A total of 326 patients met the inclusion criteria; 43 (13.2%) patients met criteria for pseudarthrosis, of whom 15 (34.9%) underwent revision surgery. There were no significant differences between patients with and those without pseudarthrosis, respectively, for patient age (54.1 vs 53.8 years), sex (34.9% vs 47.4% male), race, prior cervical spine surgery (37.2% vs 33.6%), tobacco abuse (16.3% vs 14.5%), chronic kidney disease (2.3% vs 2.8%), and diabetes (18.6% vs 14.5%) (p > 0.05). Presence of osteopenia or osteoporosis (16.3% vs 3.5%) was associated with pseudarthrosis (p < 0.001). Implant type was also significantly associated with pseudarthrosis, with a 16.4% rate of pseudarthrosis for patients with polyetherethereketone (PEEK) implants versus 8.4% for patients with allograft implants (p = 0.04). Average lengths of follow-up were 27.6 and 23.8 months for patients with and those without pseudarthrosis, respectively. Multivariate analysis demonstrated osteopenia or osteoporosis (OR 4.97, 95% CI 1.51–16.4, p < 0.01) and usage of PEEK implant (OR 2.24, 95% CI 1.04–4.83, p = 0.04) as independent predictors of pseudarthrosis. CONCLUSIONS In patients who underwent single-level ACDF, rates of pseudarthrosis associated with the use of the osteobiologic agent Osteocel are higher than the literature-reported rates associated with the use of alternative osteobiologics. This is especially true when Osteocel is combined with a PEEK implant.

scholarly journals Examining the Range of Motion of the Cervical Spine: Utilising Different Bedside Instruments

2021 ◽  
Vol 28 (2) ◽  
pp. 100-105
Author(s):  
Aiman Asyraf Ahmad Sukari ◽  
Sarwinder Singh ◽  
Muhammad Hafiz Bohari ◽  
Zamzuri Idris ◽  
Abdul Rahman Izaini Ghani ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Range Of Motion ◽  
Clinical Examination ◽  
Lateral Flexion ◽  
Range Of Movement ◽  
Cervical Range Of Motion ◽  
Accuracy And Precision ◽  
Flexion Extension ◽  
Measuring Tape ◽  
Examination Techniques

Background: This paper outlines a summary of examination technique to identify the range of movement of the cervical spine. Due to common difficulties in obtaining tools for cervical examination within the district, a standardised compilation of easy-to-replicate examination techniques are provided using different tools. Methods: Bedside instruments that can be used includes a measuring tape, compass, goniometer, inclinometer and cervical range of motion (CROM) instrument. Discussion: Cervical flexion-extension, lateral flexion and rotation will be assessed with bedside instruments. This would aid in increasing accuracy and precision of objective measurement while conducting clinical examination to determine the cervical range of motion.

Sign in / Sign up

Export Citation Format

Share Document