Related Experiment Video
Updated: Jul 30, 2026

07:51
Acrylic Resin Molding Based Head Fixation Technique in Rodents
Published on: January 12, 2016
11.7K
Transdiscal Fixation for Dropped Head Syndrome: A Case Report
Masato Tanaka1,2, Ahmed Heydar3, Muhamd A Rahmen1
1Orthopedic Surgery, Okayama Rosai Hospital, Okayama, JPN.
Cureus
|March 17, 2025
Summary
Dropped head syndrome (DHS) involves neck extensor weakness, causing chin-on-chest deformity. A novel C-arm-free technique for transdiscal fixation offers a potential solution for surgical intervention in these patients.
Area of Science:
- Neurosurgery
- Orthopedic Surgery
- Spinal Surgery
Background:
- Dropped head syndrome (DHS) is a rare neuromuscular disorder characterized by severe neck extensor muscle weakness.
- Key symptoms include chin-on-chest deformity, neck pain, and difficulties with eating and maintaining horizontal gaze, significantly impacting daily life.
- Surgical spinal fusion is often required for severe cases, but complications like distal junctional failure are common in elderly patients with osteoporosis.
More Related Videos
Related Concept Videos
Deformation of Member under Multiple Loadings
When a rod is made of different materials or has various cross-sections, it must be divided into parts that meet the necessary conditions for determining the deformation. These parts are each characterized by their internal force, cross-sectional area, length, and modulus of elasticity. These parameters are then used to compute the deformation of the entire rod.
In the case of a member with a variable cross-section, the strain is not constant but depends on the position. The deformation of an...
In the case of a member with a variable cross-section, the strain is not constant but depends on the position. The deformation of an...
Transformation of Plane Stress
Studying stress transformation is essential in understanding how stress components within a material, like a cube under plane stress, change with rotation. This change is analyzed by considering a prismatic element within the cube. As the element rotates, the stress components acting on it—both normal and shearing stresses—change in magnitude and orientation. This change is quantified using trigonometric functions of the rotation angle, relating the forces acting on the rotated element's faces...
Routh-Hurwitz Criterion I
Consider an electrical power grid, where stability is essential to prevent blackouts. The Routh-Hurwitz criterion is a valuable tool for assessing system stability under varying load conditions or faults. By analyzing the closed-loop transfer function, the Routh-Hurwitz criterion helps determine whether the system remains stable.
To apply the Routh-Hurwitz criterion, a Routh table is constructed. The table's rows are labeled with powers of the complex frequency variable s, starting from the...
To apply the Routh-Hurwitz criterion, a Routh table is constructed. The table's rows are labeled with powers of the complex frequency variable s, starting from the...
Routh-Hurwitz Criterion II
In the application of the Routh-Hurwitz criterion, two specific scenarios can arise that complicate stability analysis.
The first scenario occurs when a singular zero appears in the first column of the Routh table. This situation creates a division by zero issues. To resolve this, a small positive or negative number, denoted as epsilon (∈), is substituted for the zero. The stability analysis proceeds by assuming a sign for ∈. If ∈ is positive, any sign change in the first column of the Routh...
The first scenario occurs when a singular zero appears in the first column of the Routh table. This situation creates a division by zero issues. To resolve this, a small positive or negative number, denoted as epsilon (∈), is substituted for the zero. The stability analysis proceeds by assuming a sign for ∈. If ∈ is positive, any sign change in the first column of the Routh...

