The Mechanism of the Normal Spine and Its Relation to Scoliosis

Abstract

The present paper is an attempt to investigate the normal movements of the human spine and their relation to scoliosis. It is a carrying forward of certain preliminary work already published in which three points in spinal movements were demonstrated and considered in their bearing on scoliosis. These points were:(1) Side bending and rotation of the spine are parts of one compound movement and cannot be disassociated. There are, therefore, only three spinal movements, (a) flexion or forward bending; (b) extension or backward bending, and (c) side-bending rotation.(2) The rotation which accompanies side bending varies widely in its type between side bendings given in the flexed position of the spine and side bendings in the hyperextended position.(3) Every rotation movement of the spine must be accompanied by side bending or lateral curving of the spine.In the present paper after a statement of the conditions under which the work was done, there will follow, (a) a description of each of the spinal movements; (6) a description of the characteristic movements in the cervical, dorsal and lumbar regions, and (c) an application of these facts to the question of scoliosis.The study of scoliosis has been made almost wholly from the pathological end. This method has contributed to us a great amount of information and has done much to clear up the subject, but of late little progress has been made. It is as if one undertook, for example, to investigate a railroad accident solely from a study of the wrecked cars. Much could be learned as to the effect and direction of the destructive forces, the amount of force expended, and the kind of damage done, but more could be learned and future accidents could be better prevented by a study of the normal running time of the trains, their proper relation to each other at the time of the accident, and by an investigation of the signal system and the routine precautions adopted. In a similar way we have, I think, much to learn from the normal spine that might help our study of scoliosis. Its normal mobility, its restrictions, and its weakest points of resistance might all form part of our knowledge.In an attempt to carry on my investigation from the point mentioned the literature was first looked into. The Weber Brothers, v. Meyer, Volkmann, Hughes, Schulthess and others have contributed to our knowledge, but nowhere can be found an accurate, concise, clean-cut description of spinal movements. It, therefore, remained to attack the question of normal spinal movements and the same course as in the pre-vious investigation was adopted. Observations were made on the cadaver, these were checked on a living model and on living children.The anatomical work was done in the Anatomical Department of the Harvard Medical School under the supervision of Prof. Thomas Dwight to whom I am indebted for constant counsel and help as well as for an abundant supply of anatomical material; and from Mr. Charles P. Heath,of the second-year class of the Harvard Medical School, I had the greatest help and the mo...

Kinematics of the lumbar spine in trunk rotation: in vivo three-dimensional analysis using magnetic resonance imaging

“…In 1905, Lovett confirmed concomitant spinal motions other than the primary motion using cadaver spines and documented so-called coupled motions for the first time [7]. Quantitative data on 3D intervertebral motions of the lumbar spine have been provided by in vitro studies using cadaver specimens.…”

“…Conversely, in vivo 3D normal kinematics of the lumbar spine has not been well analyzed. So far, in vivo lumbar spinal motions have been largely analyzed by the two-dimensional (2D) methods using X-rays, fluoroscopy, and 2D-MRI [7][8][9]13]. However, previously reported 2D methods are not able to analyze 3D coupled motions of the lumbar spine.…”

“…spines and documented so-called coupled motions for the first time in 1905 [7]. Panjabi et al [11] reported in vitro three-dimensional (3D) intervertebral motions of the lumbar spine quantitatively.…”

Coupling Behavior of the Cervical Spine: A Systematic Review of the Literature

“…None of the 2D articles reported the sex, age, ethnicity, or disease process within the studies. One study used clinical observation of passive and active movements, 15 whereas another used clinical palpation of passive movement during assessment of directional coupling movement. 16 Lovett 15 used cadaveric specimens placed on a wooden slab and passively moved to reproduce coupling behavior.…”

“…33 In 1954, Fryette's findings were published and were largely based upon the findings of Lovett. 15 Fryette's perception of coupling of the cervical region was that, b. . .…”