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History and Terminology
History | 3 | Terminology | 5 |
History
Spinal degenerative changes and intervertebral disk diseases are as old as humanity itself. Skeletal remains from all periods, from the era of early humans to modern times, yield plentiful evidence of damage to the vertebral column by wear and tear. Even though intervertebral disk diseases and the related pains in the shoulders, neck, low back, and lower limb are now quite common and are often held to be “diseases of civilization,” it turns out that our remote forebears suffered from them as well. Nor can it be said that the high prevalence of these conditions merely reflects today’s longer life expectancy, because they often affect relatively young people.
It is remarkable that the syndrome of lumbar disk prolapse with sciatica, despite its clear-cut constellation of pathoanatomical and clinical neurological findings, was not fully understood until Mixter and Barr’ seminal publication of 1934.
Decades before Mixter and Barr, anatomical dissection methods and surgical technique had advanced to the point that their discovery could easily have been anticipated. Indeed, some of the major medical writers of the ancient world and the Middle Ages had already surmised that the cause of sciatica lay in the intervertebral disk (Table 2.1).
Author(s) | Year | Event |
---|---|---|
Hippocrates | 460–377 BC | Description of sciatica as “hip pain”; treatment by cauterization with a hot poker |
Galen of Pergamon | AD 129–199 | Lifestyle as cause of sciatica. Treatment: bloodletting in popliteal fossa, emetics |
Andreas Vesalius | 1543 | Thorough description of the intervertebral disks |
Sydenham | 1624–1689 | Coins the term “lumbago”; treatment by vomiting, purging, and sweating |
Cotugno | 1736–1822 | Precise description of the signs and symptoms of sciatica. Treatment with warm compresses, massage, poultices |
Bretschneider | 1847 | Describes the so-called sciatic pressure points |
Valleix | 1852 | Re-describes the “Valleix” pressure points already described by Bretschneider |
Lasègue | 1864 | Describes sciatica in Considérations sur la sciatique |
Charcot | 1888 | Thorough description of the postural abnormality accompanying sciatica |
Krause and Oppenheim | 1909 | Cauda equina compression by disk tissue |
Goldthwait | 1911 | Recognition of intervertebral disk lesions as a cause of sciatica and cauda equina compression |
Dandy | 1919 | Description of pneumoencephalography (and pneumomyelography) |
Sicard and Forestier | 1922 | Injection of lipiodol into the lumbar theca as a positive contrast medium for the localization of spinal tumors |
Schmorl | 1928 | Description of disk herniation into the vertebral body (Schmorl’s nodes) |
Mixter and Barr | 1934 | Description of disk herniation as a cause of sciatica; treatment by operative removal of the prolapsed material via hemilaminectomy |
Bärtschi-Rochaix | 1949 | Degenerative changes of the cervical disks as a cause of “cervical migraine” |
Junghanns | 1951 | Coins the term “motion segment,” laying the groundwork for the modern biomechanical and biochemical understanding of the disk |
L. Smith | 1964 | Intradiscal chymopapain injection for the treatment of disk protrusions |
Oldendorf, Hounsfield, Ambrose | 1961, 1973, 1973 | Development of compter tomography (CT) for pathoanatomical diagnosis of many conditions, including spinal diseases |
Lauterbur, Mansfield | 1973 | Development of magnetic resonance imaging (MRI) |
Pre-Christian Times
Hippocrates (460–437 BC), for example, described a patient with pain in the hip, lower portion of the sacrum, and buttock, radiating into the leg. His treatment consisted, among other things, of baths and warm compresses, both of which are still in use today (Hippocrates 1897).
AD 1–1700
Galen of Pergamon (AD 128–199) held that certain aspects of the patient’s lifestyle, such as sexual excess, over-consumption of wine, and idleness, were major contributing causes of sciatica. His treatment consisted in purification of the body, e. g., by bloodletting.
There were no major advances in the understanding of intervertebral disk disease for many centuries thereafter, notwithstanding the first precise description of the intervertebral disk by Vesalius in 1543 (see References) and the description of lumbago by Sydenham (1624–1689).
1700–1900
It was not until 1764 that Cotugno (1736–1822) published the first comprehensive work dealing with sciatica, De ischiade nervosa commentarius (“remarks on nervous sciatica”). His observations regarding diagnosis and treatment advanced the understanding of this condition so greatly that it came to be known in medical circles as “malum Cotunii”—Cotugno disease. The decades that followed saw further advances by others whose names are connected with clinical tests that are still in use today. The pressure points along the course of the sciatic nerve that were described by Valleix in 1852 are still known by his name, even though they had already been precisely described by Bretschneider 5 years earlier. One searches in vain for the sciatic nerve stretch test, the so-called “Lasègue test,” in Considérations sur la sciatique, Lasègue’s magnum opus of 1864; it was first described in writing in 1881 by Lasègue’s former student, Forst (cited in Finneson 1980).
The markedly abnormal posture of the trunk that accompanies sciatica due to disk prolapse was presumably known to physicians of earlier centuries but was first correctly described in 1888 by Charcot, the pioneer neurologist of Paris.
From 1900 Onward
Even though Charcot had already associated sciatica with a problem in the lumbar spine, the crucial observation that intervertebral disk lesions could cause cauda equina compression and sciatica was first made decades later by Krause and Oppenheim (1909) and by Goldthwait (1911). No further studies on the subject were made right away; it took 20 years for others to become convinced of the correctness of Goldthwait’s idea by corroborating it in their own, larger series of patients. The decisive factor was the development of radiological studies involving the intraspinal injection of contrast substances—first air, as used by Dandy (1919), and then lipiodol, as used by Sicard and Forestier (1922). Regrettably, the pathologist Schmorl, who published his systematic study of the spine in 1928, lacked contact with clinicians who treated patients suffering from low back pain and sciatica. Otherwise, he and his co-workers would surely have grasped the clinical importance of their many discoveries. He described protuberances from the surface of the vertebral body (osteophytes), narrowing of the intervertebral disk, destruction of the anulus fibrosus, and displacement of disk tissue into the spongiosa of the vertebral body in what are now called Schmorl’s nodes.
Finally, the seminal paper on intervertebral disk disease was published in 1934 by Mixter and Barr, who clearly described the production of sciatica by lumbar disk herniation and demonstrated the effectiveness of surgical treatment in 58 patients. Further improvements in the diagnosis and treatment of lumbar disk herniation came in the following years and decades.
This recognition of the mechanically induced degenerative changes of the intervertebral disk as the major pathogenetic factor in disk disease was followed, in the ensuing decades, by further study of the biomechanical and biochemical properties of the disk. Junghanns (1951) brought about a significant advance by identifying the motion segment as the functional unit of the spine.
The introduction and further refinement of magnetic resonance imaging (MRI; Lauterbur and Mansfield 1973) was a major advance in the radiological depiction of intervertebral disk diseases. In recent years, MRI has largely replaced earlier, invasive diagnostic techniques, such as discography and myelography; computer tomography (CT), too, which involves ionizing radiation, is now losing ground to MRI as the imaging study of choice.
More information on current developments in spinal surgery, including minimally invasive techniques, can be found in Krämer (2004) and in Bornstein, Wiesel, and Boden (2001).
Terminology
All diseases that arise directly or indirectly from pathology of the intervertebral disks are designated “intervertebral disk diseases” or “discogenic diseases.”
Anatomy and Pathology
The category of discogenic diseases is broadly defined, so that it also includes conditions whose symptoms arise from the intervertebral joints and ligaments, but whose ultimate cause lies in pathological processes of the intervertebral disk. The disk is a biomechanical unit, even though the tissues that constitute it do not have a single embryological origin. At autopsy, a single, disk-shaped structure can easily be dissected free of the vertebral end plates above and below. The intervertebral disk lacks some of the structures that would be needed to classify it as a joint or half-joint (von Luschka 1858); it was more correctly called a synchondrosis by Lindemann and Kuhlendahl (1953).
The structures linking the articular facets of two adjacent vertebrae are true joints and are called the intervertebral joints.