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Showing papers in "Spine in 1983"


Journal ArticleDOI
01 Mar 1983-Spine
TL;DR: The development and validation of a questionnaire designed to measure selfrated disability due to back pain is described, which is short, simple, sensitive, and reliable.
Abstract: One of the problems in mounting a trial of treatment of back pain is the lack of suitable outcome measures. This paper describes the development and validation of a questionnaire designed to measure selfrated disability due to back pain. The questionnaire is short, simple, sensitive, and reliable. I

2,997 citations


Journal ArticleDOI
01 Nov 1983-Spine
TL;DR: The author introduces the concept of middle column or middle osteoligamentouscomplex between the traditionally recognized posterior ligamentous complex and the anterior longitudinal ligament, and the correlation between the three-column system, the classification, the stability, the therapeutic indications are presented.
Abstract: From a retrospective study of 412 thoracolumbar injuries, the author introduces the concept of middle column or middle osteoligamentous complex between the traditionally recognized posterior ligamentous complex and the anterior longitudinal ligament. This middle column is formed by the posterior wall of the vertebral body, the posterior longitudinal ligament and posterior annulus fibrosus. The third column appears crucial, as the mode of its failure correlates both with the type of spinal fracture and with its neurological injury. Spinal injuries were subdivided into minor and major. Minor injuries are represented by fractures of transverse processes, facets, pars interarticularis, and spinous process. Major spinal injuries are classified into four different categories: compression fractures, burst fractures, seat-belt-type injuries, and fracture dislocations. These four well-recognized injuries have been studied carefully in clinical terms as well as on roentgenograms and computerized axial tomograms. They were then subdivided into subtypes demonstrating the very wide spectrums of these four entities. The correlation between the three-column system, the classification, the stability, and the therapeutic indications are presented.

2,176 citations


Journal ArticleDOI
01 Mar 1983-Spine
TL;DR: The controlled trial showed a statistically significant better result in the surgically treated group at the one-year follow-up examination, but after four years the operated patients still showed better results, but the difference was no longer statistically significant.
Abstract: Two hundred eighty patients with herniated lumbar discs, verified by radiculography, were divided into three groups. One group, which mainly will be dealt with in this paper, consisted of 126 patients with uncertain indication for surgical treatment, who had their therapy decided by randomization wh

1,026 citations


Journal ArticleDOI
01 Oct 1983-Spine
TL;DR: Operative results in the patients with cervical OPLL, spondylosis, and canal stenosis were satisfactory, and optimal widening of the AP diameter of the spinal canal is considered to be over 4 mm.
Abstract: Although the operative results have been improving since the air drill was introduced for cervical laminectomy instead of an ordinary rongeur, post-laminectomy complications, such as postoperative fragility of the cervical spine to acute neck trauma, posterior spur formation at the vertebral body, and malalignment of the lateral curvature have still remained as unsolved problems. In order to avoid these disadvantages, a new surgical technique called "expansive open-door laminoplasty" was devised by the author in 1977, which is relatively easier, safer, and better than the ordinary laminectomy from the standpoint of structural mechanics of the cervical spine. The operative procedure is described in detail. Operative results in the patients with cervical OPLL, spondylosis, and canal stenosis were satisfactory, and optimal widening of the AP diameter of the spinal canal is considered to be over 4 mm. From this procedure a bilateral, open-door laminoplasty has been devised for extensive exploration at the intradural space.

710 citations


Journal ArticleDOI
01 Apr 1983-Spine
TL;DR: The distribution of the intrinsic nerves of the lumbar vertebral column systematically identifies those structures that are potential sources of primary low-back pain.
Abstract: The lumbar intervertebral discs are innervated posteriorly by the sinuvertebral nerves, but laterally by branches of the ventral rami and grey rami communicantes. The posterior longitudinal ligament is innervated by the sinuvertebral nerves and the anterior longitudinal ligament by branches of the grey rami. Lateral and intermediate branches of the lumbar dorsal rami supply the iliocostalis lumborum and longissimus thoracis, respectively. Medial branches supply the multifidus, intertransversarii mediales, interspinales, interspinous ligament, and the lumbar zygapophysial joints. The distribution of the intrinsic nerves of the lumbar vertebral column systematically identifies those structures that are potential sources of primary low-back pain.

483 citations


Journal ArticleDOI
01 Mar 1983-Spine
TL;DR: The natural history of the symptom of low-back pain has been described and clinical features predictive of outcome have been identified in order to define groups of patients who were relatively homogeneous with respect to the outcome of the episode.
Abstract: In a prospective study of 230 episodes of low-back pain presenting in primary care, the natural history of the symptom of low-back pain has been described. Clinical features predictive of outcome have been identified in order to define groups of patients who were relatively homogeneous with respect

473 citations


Journal ArticleDOI
01 Apr 1983-Spine
TL;DR: In this paper, the authors reviewed the hip-spine syndrome in thirty-five patients and found that the finding and diagnosis were straight forward, and were classified as a simple hip spine syndrome.
Abstract: Thirty-five patients were reviewed with what is called hip-spine syndrome. Concurrent disease at both the hip and spine is not infrequent in the older population. In most cases, the finding and diagnosis were straight forward, and were classified as a simple hip-spine syndrome. Cases in which the spine symptoms are aggravated by deformity of the hip were called a secondary hip-spine syndrome. Symptomatic disease at both the hip and spine can present as a complex hip-spine syndrome. Symptoms from both sites gives a confusing clinical picture and may require ancillary investigations to diagnose the major source of disability. Failure to recognize concurrent disease at both the hip and spine may lead to misdiagnosis and possibly erroneous treatment.

373 citations


Journal ArticleDOI
01 Sep 1983-Spine
TL;DR: In the majority of cases, the chronic or recurrent sciatic pain and unilateral hip symptoms occurred on the side of the longer lower extremity, and when correcting the leg length inequality simply with an adequate shoe lift, a permanent and mostly complete alleviation of symptoms was achieved.
Abstract: A simple and reliable low dose radiologic method developed by the author was used to measure leg length inequality of 798 patients with chronic and therapy resistant low-back and/or unilateral hip symptoms and 359 symptom free subjects. Statistically highly significant correlations of the symptoms and leg length inequality were observed. In the majority (79 and 89%), the chronic or recurrent sciatic pain and unilateral hip symptoms occurred on the side of the longer lower extremity. When correcting the leg length inequality simply with an adequate shoe lift, a permanent and mostly complete alleviation of symptoms was achieved in the majority of the cases. The unilateral symptoms associated with mostly unrecognized leg length inequality of 5 to 25 mm were, at least in part, due to the biomechanical responses, like bending and rotational forces, needed for compensation of the lateral imbalance caused by leg length inequality.

369 citations


Journal ArticleDOI
01 Sep 1983-Spine
TL;DR: Although, as a group, the operated patients were functionally and socially very well indeed, low-back pain was found statistically significantly more often in patients in whom fusion was carried down to L4 or L5, compared to the control subjects.
Abstract: One hundred patients from the Gothenburg Scoliosis Data Base were studied. They met the following criteria: (1) adolescent idiopathic scoliosis (2) completion of treatment before age 20, (3) a minimum follow-up of five years thereafter, (4) a minimum age of 22 years at final follow-up, and (5) operation performed by the senior author. Of these, 95 were personally examined. The surgical technique from 1968 to 1973 included a two-stage Harrington distraction, with fusion added at the second operation (52 patients). From 1973 to 1975, 48 patients were treated with a one-stage distraction and fusion after a week of preoperative Cotrel traction. Postoperatively, all patients were treated with a Milwaukee brace. A spinal examination and functional assessment, including a questionnaire and pain drawing, full standing anterior-posterior (AP), and lateral roentgenograms of the spine, was performed by independent observers. Eighty-five subjects without scoliosis served as a control group. The radiographic evaluation showed the usual nearly 50% permanent correction at the follow-up examination averaging nine years postoperatively. Lateral roentgenograms, however, demonstrated in 52% flattened or kyphotic cervical spines producing no significant complaints, non-significant flattening of the thoracic kyphosis, but significant lowering of the lumbar lordosis. Fifteen of the 24 patients with distal hook insertion and fusion including L4 or L5 demonstrated retrolisthesis. All had significant low-back pain. Degenerative facet joint changes and disc space narrowing was noted in 11 patients, again with a distal hook purchase in L4 or L5. Compared to the controls, the operated patients, as a group, revealed no lessened activity or back pain at any location.(ABSTRACT TRUNCATED AT 250 WORDS)

361 citations


Journal ArticleDOI
01 Apr 1983-Spine
TL;DR: Experiments were carried out on cadaveric lumbar spines to determine the mechanical function of the apophyseal joints and it was found that they resist most of the intervertebral shear force and share in resisting the interVertebral compressive force, but only in lordotic postures.
Abstract: Experiments were carried out on cadaveric lumbar spines to determine the mechanical function of the apophyseal joints. It was found that they resist most of the intervertebral shear force and share in resisting the intervertebral compressive force, but only in lordotic postures. They prevent excessi

351 citations


Journal ArticleDOI
01 Sep 1983-Spine
TL;DR: It is concluded that fluid flow in flexed postures can aid the nutrition of the lumbar discs.
Abstract: Cadaveric lumbar motion segments were creep loaded for 4 hours, and the fluid content of the intervertebral discs was measured and compared with that of unloaded discs. Half of the specimens were wedged to simulate sitting with the lumbar spine flexed, and the other half were wedged to simulate sitting or standing erect. The results showed that "flexed" discs lost more fluid, especially from the nucleus pulposus, than did the "erect" discs. It is concluded that fluid flow in flexed postures can aid the nutrition of the lumbar discs.

Journal ArticleDOI
01 Jan 1983-Spine
TL;DR: Nine patients with cervical spondylotic myelopathy, diagnosed during life, were subjected to detailed clinicopathologic study and recurrent trauma proved to cause distinct manifestations and cord pathology.
Abstract: Nine patients with cervical spondylotic myelopathy, diagnosed during life, were subjected to detailed clinicopathologic study. The degree of cord destruction was in good correlation with the ratio of the anteroposterior diameter to the transverse diameter, designated as an anteroposterior compression ratio. Within the factors responsible for decrease in the ratio, developmental narrowing of the spinal canal was the most significant, and multiplicity of spondylotic protrusion less so. The former resulted in an extensive demyelination of the posterolateral funiculus and infarction of the gray matter. Recurrent trauma proved to cause distinct manifestations and cord pathology. Clinicopathologic correlations were also examined from the neurologic findings at the terminal stage.

Journal ArticleDOI
01 Apr 1983-Spine
TL;DR: The relationship of low-back pain to work history and work environment factors was studied in a randomized sample of 940 men from 40 to 47 years of age and ten of the variables studied were found to be correlated to the occurrence of LBP.
Abstract: The relationship of low-back pain (LBP) to work history and work environment factors was studied in a randomized sample of 940 men from 40 to 47 years of age. The life-time incidence of LBP was 61%, the prevalence 31%. In a univariate analysis ten of the variables studied were found to be correlated to the occurrence of LBP: less overtime work, diminished work satisfaction, decreased potential to influence the work situation, lesser demand on concentration, monotonous work, physically heavy work, a high degree of lifting, to a lesser degree sitting, and to a greater standing and walking work posture. When a covariance analysis was applied to these variables, only three had a direct association to LBP. They were less overtime work, monotonous work, and a high degree of lifting.

Journal ArticleDOI
01 Nov 1983-Spine
TL;DR: Data as presented here can be used to study the effect of intervention (for example, manual therapy) on the natural course of work recovery, and to study differences in sickness absence patterns between different diagnoses and work groups.
Abstract: The intensity of work recovery in LBP has been studied using the National Health Register. Nine hundred forty men, 40-47 years old, were selected randomly from the census register of the city of Goteborg, Sweden. Sickness absence data were obtained from the Health Register, in which all sickness absence from age 16 is recorded. The rate of return to work decreases as expected with an increase in absence period. Different rates were found for different diagnoses, however, with low return intensities in patients with sciatica compared with those with back pain, ie, return to work was slower in patients with sciatica. Men with manual work had a significantly longer average sickness absence than white-collar workers. The intensity of work recovery was lower in blue-collar workers during the first 20 days of absence, while the reverse was true after 20 days of sickness absence, ie, the white-collar workers who were absent more than 20 days had a slower rate of recovery than blue-collar workers who had been absent for 20 days. Data as presented here can be used to study the effect of intervention (for example, manual therapy) on the natural course of work recovery. It also can be used, as above, to study differences in sickness absence patterns between different diagnoses and work groups.

Journal ArticleDOI
01 Mar 1983-Spine
TL;DR: This study indicates that the load on the remaining facet is reduced substantially after a facetectomy although peak pressure increases, and demonstrates the substantial difference in facet loadings between L2-L3 segments and L4-L5 segments.
Abstract: An in-vitro experimental study was carried out to measure the induced loading on human lumbar facets due to varying amounts of compressive axial load. Testing was done on L2-L3 and L4-L5 spinal motion segments obtained from cadavers at autopsy. The compressive loading was applied to the spinal speci

Journal ArticleDOI
01 Nov 1983-Spine
TL;DR: The findings do indicate that spinal movements, over a longer period of time give rise to positive nutritional variations, and might be of significance also for the human lumbar disc problem, since previous studies have demonstrated nutritional similarities between the discs of dogs and men.
Abstract: In this experiment study, we have investigated some transport and metabolic parameters of the canine intervertebral disc induced by spinal motion. The movements of the spine were obtained during supervised exercise, where either moderate, violent, or specific movements were performed. The results show changes in the metabolic rates as well as in concentration profiles of metabolites of the exercised groups in comparison to the control group. An increasing aerobic metabolism was noted in the outer part of the annulus and in the central part of the nucleus pulposus, resulting in a reduction of the lactate concentration. These findings do indicate that spinal movements, over a longer period of time give rise to positive nutritional variations. Furthermore, the reported changes might be of significance also for the human lumbar disc problem, since previous studies have demonstrated nutritional similarities between the discs of dogs and men.

Journal ArticleDOI
01 Nov 1983-Spine
TL;DR: The results confirm the prediction that the axial endplate bulge is comparable in magnitude to the linear compression of the motion segment and are important determinants for the compression characteristics of the human spine.
Abstract: When the published data on the radial disc bulge in relation to the axial compression of the motion segment are compared to a simple mechanical model, it follows that an axial inward bulge of the vertebral endplates should occur during compression. The model predicts that the disc height at its center should remain practically constant under compression. The axial endplate bulge has been measured in specimens of the human lumbar spine by stereoroentgen-photogrammetric methods. The results confirm the prediction that the axial endplate bulge is comparable in magnitude to the linear compression of the motion segment. Axial endplate bulge and deformation of the underlying trabecular bone are thus important determinants for the compression characteristics of the human spine.

Journal ArticleDOI
01 Sep 1983-Spine
TL;DR: A “health status” questionnaire, the Sickness Impact Profile (SIP), which comprehensively assesses a wide range of dysfunctions is examined to assess its measurement characteristics in patients with mechanical low-back pain.
Abstract: Techniques for assessing daily function in Patients with back pain are generally crude and limited in scope. We therefore examined a "health status" questionnaire, the Sickness Impact Profile (SIP) to assess its measurement characteristics in such patients. Eighty patients with mechanical low-back pain completed the SIP and a physical examination at a walk-in visit and again three weeks later. Test-retest reliability of the SIP was substantial. Biologic validity was confirmed by significant correlations with age, pain duration, spine flexion, straight leg raising, and pain severity. Validity of psychosocial subscales was confirmed by significant associations with patient anxiety and psychiatric problems. Scores changed in the expected directions when patients were evaluated three weeks later. The SIP is thus valid, reliable, sensitive to clinical changes, and comprehensively assesses a wide range of dysfunctions.

Journal ArticleDOI
01 Jul 1983-Spine
TL;DR: There was an evolution in the type of posterior instrumentation used over the 12 years and better results were obtained by using segmental spinal fixation in the form of sublaminar wiring of double Luque rods.
Abstract: Forty-five skeletally mature patients averaging 44.3 years of age had spinal fusions which extended to the sacrum for pain and/or progression of their scoliosis. The primary diagnosis was idiopathic scoliosis in 35 patients, congenital scoliosis in two patients, and paralytic scoliosis in eight patients. A single curve pattern was present in 41 patients and the remainder had double primary curves. Thirty-eight patients had single stage procedures and 35 of these were done posteriorly. There was an evolution in the type of posterior instrumentation used over the 12 years. Thirty-five patients (78%) had at least one significant postsurgical complication. Thirteen of 22 patients with loss of lordosis required corrective osteotomies. Other complications included pseudoarthrosis in ten patients and neurologic complications in five patients, four of which had complete recovery. Twenty-five patients required a total of 51 subsequent surgical procedures. Despite a 51% initially poor result and a high complication rate, the final results were good or fair in 93% of the patients. This change was primarily the result of successful subsequent surgical procedures for correction of loss of lordosis and pseudoarthrosis. The adult scoliosis patient should be fused to the sacrum only if the lumbosacral disc is clearly a source of pain or the degree of pelvic obliquity makes it necessary in the paralytic curve. Every effort must be made to carefully preserve the patient's lumbar lordosis. Better results were obtained by using segmental spinal fixation in the form of sublaminar wiring of double Luque rods.

Journal ArticleDOI
01 May 1983-Spine
TL;DR: The author was neither able to identify definitive contributing factors for olisthesis, nor able to confirm the previously reported factors: young age, normal disc heights, and multiple level decompression in this review study.
Abstract: Twenty-seven patients who underwent extensive posterior spinal decompression procedures were reviewed to investigate the incidence, the clinical significance and contributing factors of the postdecompression olisthesis, and indication for spinal fusion at the time of extensive decompression. Eleven patients were female and 16 were male. The mean age was 49.4 years. Twenty-two patients were treated with extensive decompression and spinal fusion, and five patients were treated with decompression alone without spinal fusion. The average follow-up time was 2 1/2 years (1-4 1/2). The incidence of newly developed postdecompression olisthesis was 3.7% (1/27) and all four patients with preoperative spondylolisthesis progressed further postoperatively. The author was neither able to identify definitive contributing factors for olisthesis, nor able to confirm the previously reported factors: young age, normal disc heights, and multiple level decompression in this review study. The incidence rate of pseudarthrosis was high (27.3%) after the extensive posterior decompression and fusion. The concomitant spinal fusion is not routinely indicated to patients with extensive posterior spinal decompression. Furthermore, it does not appear to be effective in prevention of olisthesis. The concomitant spinal fusion should be exceptional rather than routine.

Journal ArticleDOI
01 Oct 1983-Spine
TL;DR: Back pain in a referred and followed group of 197 adults with idiopathic scoliosis and in a comparable control group of 180 adults without known spinal deformity was the same; Severity of pain, however, was greater in scoliotic patients.
Abstract: Incidence of back pain in a referred and followed group of 197 adults with idiopathic scoliosis and in a comparable control group of 180 adults without known spinal deformity was the same. Severity of pain, however, was greater in scoliotic patients. The clinical course of back pain in adults without spinal deformity and in scoliotics was different: 64% improvement in adults without scoliosis versus 83% persistence and progression in adults with scoliosis. Fifty-one percent of adult scoliotics (101 patients) had significant pain. Pain increased with age and degree of scoliotic curvature (P less than 0.0005). Patients with major lumbar curves had more pain. Major complaint was frequently below major deformity. Compensatory lumbosacral fractional curves were most painful and disabling. Pain comes mainly from concavity of curves and includes discogenic, facet joint, and radicular origins. Surgery significantly reduced pain (P less than 0.0001); conservative therapy did not. Eighty-three percent of surgical patients had sufficient pain relief to make surgery worthwhile at five years average follow-up.

Journal ArticleDOI
01 Jan 1983-Spine
TL;DR: A quantitative study of the trunk Muscle strength and fatigability was performed using an isokinetic dynamometer to determine the role of trunk muscles in the low-back-pain syndrome and in particular to investigate the correlation of trunk muscle strength and lumbar lordosis.
Abstract: A quantitative study of the trunk muscle strength and fatigability was performed using an isokinetic dynamometer to determine the role of trunk muscles in the low-back-pain syndrome and in particular to investigate the correlation of trunk muscle strength and lumbar lordosis. Most patients demonstrated a generalized weakness of the trunk muscles. The trunk muscle strength of patients suffering from backache for less than one month was significantly lower than that of the controls. The strength of the trunk muscles was not influenced by the duration of symptoms. There was no imbalance between the trunk flexors and extensors. The patients with back pain had a greater fatigability of the trunk flexors than the controls. There was negative correlation between the trunk muscle strength or fatigue and lumbar lordosis.

Journal ArticleDOI
01 Jul 1983-Spine
TL;DR: Seventy-nine patients, 51 with a fresh neurologic deficit, underwent anterior spinal cord decompression, block bone grafting and anterior internal fixation, with the more recent use of an anterior Harrington distraction system allowing for greater correction of kyphotic deformities and more rigid internal fixation which in time allows for early ambulation in a brace.
Abstract: Seventy-nine patients, 51 with a fresh neurologic deficit, underwent anterior spinal cord decompression, block bone grafting and anterior internal fixation. AO plates were used in nine patients. Dwyer cables in 15, anterior Harrington systems in 20, and solid Hall rods with Dwyer screws in 23. Cases included 13 tumors (six metastatic, five primary malignant, two benign), 15 late kyphotics (13 congenital and two old tuberculosis), 15 pyogenic (nontuberculous) infections, 32 fractures and four thoracic discs. Levels of decompression were from T5 to L5 with the majority (23) at L1. The neurologic deficit improved in 100% of those with incomplete paraplegia, and was graded according to the Frankel classification. None was made worse. Surgical indications were: progressive neurologic deficit in 51 patients, tumors in 13, correction of deformity in 55, failure of infection to respond to conservative measures in 15, cachexia in nine, (many patients had more than one indication). Bone grafts included 11 rib grafts, 24 block iliac grafts with ribs and 44 iliac block grafts. Complications included three nonunions, two common iliac vein lacerations, one death (pulmonary) and two post-thoractomy syndrome. The more recent use of an anterior Harrington distraction system allows for greater correction of kyphotic deformities and more rigid internal fixation which in time allows for early ambulation in a brace. Supplementary posterior fixation is generally no longer necessary except where more than one vertebral body is resected.

Journal ArticleDOI
01 Mar 1983-Spine
TL;DR: The abdominals were more susceptible to fatigue than the back extensors, women demonstrated more endurance than men, and the endurance for normals was less than those patients who were able to perform dynamic reciprocal trunk movements.
Abstract: A method was developed to obtain static and dynamic measures of trunk flexor and extensor strength and endurance. The method was evaluated using 32 normal subjects. Variables of trunk strength and endurance were used to compare 24 normals (12 men and 12 women) and 24 patients (16 men and eight women) with chronic low-back dysfunction. The Iowa Trunk Dynamometer is acceptably reliable and provides for assessment of isolated function of the abdominal and back muscles. For peak abdominal and back extensor strength, the range of superiority of men over women was 39-57%, and the range of superiority of normals over patients with chronic low-back dysfunction was 48-82%. Using time to percent decrement of peak strength as a criterion, the abdominals were more susceptible to fatigue than the back extensors, women demonstrated more endurance than men, and the endurance for normals was less than those patients who were able to perform dynamic reciprocal trunk movements.

Journal ArticleDOI
01 Oct 1983-Spine
TL;DR: The proportion of patients who had complete relief or only isolated transient symptoms at the five-year review showed only a very slight fall over the years, and the union rate was shown to improve with time.
Abstract: A series of 40 patients is presented at least ten years following anterior spinal fusion for intervertebral disc prolapse. The proportion of patients who had complete relief or only isolated transient symptoms at the five-year review (67.5%) showed only a very slight fall over the years (65.0%). The union rate was shown to improve with time. There was no clear evidence that anterior spinal fusion led to accelerated degeneration of adjacent intervertebral discs. The significance of posterior extension of the fusion is discussed.

Journal ArticleDOI
01 Mar 1983-Spine
TL;DR: The response to compression, shear, bending, and axial rotation of an intervertebral disc is studied by using a theoretical disc model that is modelled by ten fibre layers with alternating fibre inclination.
Abstract: The response to compression, shear, bending, and axial rotation of an intervertebral disc is studied by using a theoretical disc model. The annulus fibrosus is modelled by ten fibre layers with alternating fibre inclination. The nucleus pulposus as well as the substance filling the space between the

Journal ArticleDOI
01 Nov 1983-Spine
TL;DR: The before- and after- test radiographs showed a one-to-one correspondence between unstable specimens and generalized bony failure, and crack propagation from the periphery of the subchondral bone inward.
Abstract: A low-cycle fatigue of 11 lumbar intervertebral joints under axial compression is reported. The magnitude of the maximum compressive load ranged from 37 to 80% of the failure load. The maximum deformation, as a function of the number of cycles, showed two distinct results: one group showed a gradual, stable increase, and the other an abrupt, unstable increase. The before- and after-test radiographs showed a one-to-one correspondence between unstable specimens and generalized bony failure. The radiographs of 5-mm thick transverse endplate slices show crack propagation from the periphery of the subchondral bone inward. Removal of the organic matrix from the cracked specimens produced its physical disintegration into small particles, while normal controls and stable specimens retained their size and shape.

Journal ArticleDOI
01 Sep 1983-Spine
TL;DR: The anatomy of 54 pairs of lumbosacral nerve roots was described in nine fresh adult cadaver specimens, with particular attention given to the fixation of the nerve roots to surrounding skeletal and ligamentous structures in the lumbar spine.
Abstract: The anatomy of 54 pairs of lumbosacral nerve roots was described in nine fresh adult cadaver specimens, with particular attention given to the fixation of the nerve roots to surrounding skeletal and ligamentous structures in the lumbar spine. Dural ligaments were identified fixing the dura and nerve roots at their exit from the main dural sac to the posterior longitudinal ligament and vertebral body periosteum proximal to the intervertebral disc. Distal fixation occurs at the intervertebral foramen where the epineural sheath of the spinal nerve is attached. The overall arrangement is one which tends to hold the exiting nerve root anteriorly in the spinal canal. Mechanical analysis of this anatomical arrangement explains how pressure can be applied to the extrathecal nerve root by a disc protrusion without compression of the nerve root against the posterior elements. The possible role of the dural ligaments in the pathogenesis of the sciatica syndrome is discussed.

Journal ArticleDOI
01 Jan 1983-Spine
TL;DR: The role of the narrow cervical spinal canal in the expression of clinical syndromes in the cervical spine was investigated in a retrospective review of 63 patients with symptomatic cervical spondylosis refractory to conservative therapy.
Abstract: The role of the narrow cervical spinal canal in the expression of clinical syndromes in the cervical spine was investigated in a retrospective review of 63 patients with symptomatic cervical spondylosis refractory to conservative therapy. The measurement of the developmental segmental sagittal diameter, determined at the level of the pedicle, and of the spondylotic segmental sagittal diameter, determined at the level of the disc, were applied. When divided into groups based on anatomic variance around an average size midcervical diameter of 17 mm, 40 patients were found to have less than the average size of midcervical canal. A spondylosis index was computed for the narrow canal group at 2.08 mm per segment and for the wide canal group at 3.29. Canal dimensions are determinants of symptom production and neurologic compromise.

Journal ArticleDOI
01 Apr 1983-Spine
TL;DR: The relationship of low-back pain to other diseases and to cardiovascular risk factors was studied in a random sample of 940 men from 40 to 47 years of age.
Abstract: The relationship of low-back pain (LBP) to other diseases and to cardiovascular risk factors was studied in a random sample of 940 men from 40 to 47 years of age. The life-time incidence of LBP was 61%, the prevalence 31%. The prevalence of other diseases was the same as in previous studies in the s