Correlations and time-dependent changes of upper arm performance tests, the Japanese Orthopaedic Association score, and a newly developed patient-based outcome measure : the Japanese Orthopaedic Cervical Myelopathy Questionnaire.

AIMS: In this prospective observational study, we investigated the time-dependent changes and correlations of upper arm performance tests (ten-second test and Simple Test for Evaluating Hand Function (STEF), the Japanese Orthopaedic Association (JOA) score, and the JOA Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) in 31 patients with cervical myelopathy who had undergone surgery. PATIENTS AND METHODS: We hypothesised that all the indices correlate with each other, but show slightly different recovery patterns, and that the newly described JOACMEQ is a sensitive outcome measure. RESULTS: Peak recoveries were achieved one month post-operatively in the ten-second test and JOACMEQ upper extremity function (UEF) subscale, and at three months in the JOA and STEF scores. The recoveries of all indices were maintained until six months post-operatively. The upper extremity function (UEF) subscale in the JOACMEQ showed the strongest correlation with STEF although all the indices correlated with each other. Patients with ≥ 20 and < 20 acquired points in the UEF subscale were classified into the UEF-improved and UEF-unimproved groups. Comparisons between the groups showed that pre-operative evaluation of "coordinated motion" of the STEF was significantly low in the UEF-unimproved group. CONCLUSION: These results indicate that the JOACMEQ is a concise, sensitive, patient-based outcome measure for evaluating functional recovery in patients with cervical myelopathy who have undergone surgery. Cite this article: Bone Joint J 2016;98-B:990-6.

Long-term follow-up results of laminectomy for cervical myelopathy caused by ossification of the posterior longitudinal ligament.

OBJECT: This retrospective study was performed to assess the long-term results of cervical laminectomy in treating ossification of the posterior longitudinal ligament (OPLL) of the cervical spine. METHODS: The authors reviewed medical records in 44 of 52 patients who underwent cervical laminectomy between 1970 and 1985 (mean follow up 14.1 years). The neurological recovery rate after laminectomy was 44.2% after 1 year and 42.9% after 5 years. The surgical outcome was maintained after 5 years but worsened between 5 and 10 years postsurgery: the recovery rate at the last follow-up review was 32.8%. Using multivariate stepwise analysis, the preoperative factors that affected clinical results were found to be the age at operation, the severity of preexisting myelopathy, and a history of trauma. Late neurological deterioration was observed in 10 (23%) of 44 patients. The earliest deterioration occurred at 1 year and the latest was at 17 years postsurgery (mean 9.5 years). The most frequent cause of deterioration was trauma due to a fall (six patients), followed by ossification of the ligamentum flavum (three patients). Postoperative spread of the OPLL was noted in 70% of the patients, but it was clearly the cause of neurological deterioration in only one of them. After laminectomy, postoperative progression of kyphotic deformity was observed in 47% of patients, but these changes did not cause neurological deterioration. CONCLUSION: The authors recommend early surgical decompression for OPLL because the outcome is better for younger patients and for those with a higher score as measured by the Japanese Orthopedic Association's system.

Epidural migration of hemostatic agents as a cause of postthoracotomy paraplegia. Report of two cases.

Paraplegia secondary to pulmonary surgery occurred in two patients because of epidural migration of hemostatic agents. Computerized tomography following myelography revealed the lesion clearly. Both patients achieved satisfactory neurological recovery through prompt diagnosis and treatment.

Distribution of genes for bone morphogenetic protein-4, -6, growth differentiation factor-5, and bone morphogenetic protein receptors in the process of experimental spondylosis in mice.

OBJECT: Because little is known about the molecular mechanisms underlying the process of spondylosis, the authors examined the extent of genetic localization of several members of bone morphogenetic protein (BMP) and BMP receptors in chondrogenesis during the process of inducing spondylosis in their previously established experimental mice model. METHODS: Experimental spondylosis was induced in 5-week-old ICR mice. The cervical spine was harvested chronologically, and histological sections were prepared. Messenger RNA for BMP-4, growth and differentiation (GDF)-5, BMP-6, and BMP receptors (ALK-3, -6, and BMP-RII) was localized in the tissue sections by in situ hybridization. In the early stage, BMP-4-derived mRNA was localized mainly in cells in the anterior margin of the cervical discs, together with ALK-6 and BMP-RII mRNA. No GDF-5 and BMP-6 mRNA was detected at this stage. In the late stage, cells positive for BMP-4 decreased, whereas GDF-5 and BMP-6 mRNA were localized in cells undergoing chondrogenesis. The ALK-3 mRNA began to appear in this stage, as did ALK-6 and BMP-RII. CONCLUSIONS: The localization of transcripts for BMP-4, -6, and GDF-5 as well as BMP receptors shown during the present experimental model indicate the possible involvement of molecular signaling by these BMPs in the chondrogenic progress in spondylosis.

Thoracic myelopathy secondary to ossification of the spinal ligament.

The authors describe their experience with 26 cases of thoracic myelopathy secondary to hypertrophic ossification of the spinal ligament (posterior longitudinal ligament and/or ligamentum flavum). The clinical manifestations of this condition and results of its surgical treatment are described. The commonest symptoms were numbness or tingling in the legs and feet and gait disturbance. Most of the patients with involvement of the upper thoracic spine showed typical features of thoracic myelopathy: that is, sensory and motor deficits in both the trunk and lower extremities, sphincter disturbance, and exaggerated tendon reflexes. Several patients with involvement of the thoracolumbar junction presented with atypical symptoms of thoracic myelopathy and were sometimes misdiagnosed and treated inappropriately. Surgical treatment, particularly laminectomy, was not always successful. Inconsistencies in the surgical outcome were caused by either operative complications or reversal of the initial improvement during the follow-up period. The results of anterior surgery for the condition were more favorable; however, use of this procedure was rarely indicated.

Duplication of the thumb. A retrospective review of two hundred and thirty-seven cases.

Over a twenty-two-year period, 237 patients (261 hands) with duplication of the thumb were seen in the Hand Clinic of Osaka University Hospital. Two groups were identified: Group A, 141 patients without previous surgical treatment, and Group B, ninety-six patients with residual deformity despite previous surgical treatment. Using a modification of Wassel's classification, seven types of deformity were defined. In Group A these types were identified on the basis of the observed duplications of bone and soft tissue. In all but ten of the Group-B patients preoperative roentgenograms were not available and the type of deformity had to be deduced from the residual duplicated bone, the surgical scar, and the residual deformity. Surgery, performed on 193 hands (125 in Group A and sixty-eight in Group B), attempted to restore normal anatomical relationships. The results could be evaluated in 130 hands according to the range of motion, joint stability, and alignment of the remaining thumb after an average follow-up of 35.0 months. According to the rating system described, the results were rated as good in 75.5 per cent, fair in 20.2 per cent, and poor in 4.3 per cent of the ninety-four hands in Group-A patients who were followed. In the thirty-six hands of Group-B patients who could be followed, the preoperative and postoperative scores were compared. Thirteen were not improved while the other twenty-three, sixteen improved from fair to good and seven improved from poor to fair, to give a good result in 63.9 per cent of the Group-B patients who were followed. The results in these 130 Group-A and B hands emphasize the importance of providing muscle balance and, in young patients, of performing an arthroplasty of the interphalangeal or metacarpophalangeal joint when indicated, although arthrodesis was indicated as a salvage operation for Group-B patients who were more than fifteen years old.

Cervical radiculopathy or myelopathy secondary to athetoid cerebral palsy.

Radiculopathy or myelopathy often occurs during adult life in patients who have athetosis. Herniation of an intervertebral disc, spondylosis, malalignment or instability of the cervical spine, or a combination of these lesions, can develop because of the athetoid hyperactivity. We reviewed the cases of ten patients who had cervical radiculopathy or myelopathy, or both, secondary to athetosis and who were surgically treated between the ages of thirty and fifty-eight years. The surgery consisted of discectomy, removal of osteophytes, and anterior interbody fusion. When several segments were involved, an extensive subtotal resection of the vertebrae and discs, followed by strut bone-grafting, was done.

Experimental cervical spondylosis in the mouse.

A reproducible experimental model of cervical spondylosis in mice was established by means of detachment of the posterior paravertebral muscles from the vertebrae and resection of the spinous processes along with the supraspinous and interspinous ligaments. Mechanical instability in the cervical spine elicited by this surgical intervention accelerated the process of intervertebral disc degeneration, and when extended over a 6-12-month period, induced cervical spondylosis in the mice. The pathologic findings in the cervical intervertebral discs of this experimental model varied: proliferation of cartilaginous tissue and fissures in the anulus fibrosus, shrinkage of the nucleus pulposus, herniation of disc material, and osteophyte formation. The availability of this experimental model should be valuable for biochemical and biomechanical understanding of the pathogenesis of cervical spondylosis.

Intramedullary changes of the spinal cord in cervical spondylotic myelopathy.

STUDY DESIGN: This study retrospectively reviewed magnetic resonance imaging and delayed computed tomography after myelography of cervical spondylotic myelopathy patients who needed surgical treatment. OBJECTIVES: The purpose of this study is to clarify the meaning of high magnetic resonance intensity areas in cervical spondylotic myelopathy patients. SUMMARY OF BACKGROUND DATA: There is no conclusion whether the high magnetic resonance signal intensity areas can be a predictor for surgical results or not. METHODS: Thirty-one patients with cervical spondylotic myelopathy were examined with magnetic resonance imaging before surgery and delayed computed tomography after surgery. The presence or absence of high intensity areas in the spinal cord was compared with clinical symptoms and surgical outcomes. RESULTS: Twenty-three (74%) of 31 patients showed high intensity areas in the spinal cord on the T2-weighted image. Among these 23 patients, 18 revealed bilateral intramedullary "snake eyes" enhancement in delayed computed tomography. The presence of high intensity areas did not correlate with the surgical outcomes. Patients with multisegmental (linear) high intensity areas frequently manifested muscle atrophy in upper extremities. CONCLUSIONS: High intensity areas on T2-weighted magnetic resonance imaging were not correlated with the severity of myelopathy or surgical outcomes evaluated by the Japanese Orthopaedic Association score. Magnetic resonance imaging or delayed computed tomography in this study could not rule out the presence of white matter changes, including axonal loss or demyelination. Multisegmental (linear) high intensity areas on T2-weighted magnetic resonance imaging were associated with clinical evidence of extensive anterior horn cell and radiographic evidence of gray matter cavitation.

Postoperative cervical pseudomeningocele with herniation of the spinal cord.

STUDY DESIGN: This is a report of a patient in whom spinal cord herniation into a pseudomeningocele resulted in progressive myelopathy. OBJECTIVE: To describe the outcome of a 59-year-old man who visited Osaka University Hospital complaining of gait disturbance. He had undergone cervical laminectomy to resect a spinal cord tumor 14 years previously. SUMMARY OF BACKGROUND DATA: Pseudomeningocele is an extremely rare condition and can be overlooked. In addition, cord herniation into the pseudomeningocele rarely can be diagnosed before surgical exploration. Our patient represents the first case we are aware of in which magnetic resonance imaging could clearly demonstrate not only the pseudomeningocele, but the herniation of the cord into the cyst. METHODS: Magnetic resonance imaging was used for preoperative and postoperative investigation. RESULTS: The pseudomeningocele was resected to improve the neurologic status of the patient. During the operation, the herniated cord was successfully reduced into the original subarachnoid space by the release of adhesion. Most symptoms subsided soon after surgery. Magnetic resonance imaging could delineate not only the cyst and cord herniation, but the medullary pathology. The distribution of high-intensity areas on T2-weighted images suggested the cord damage. CONCLUSION: Magnetic resonance imaging revealed not only the cyst and cord herniation, but medullary pathology, too.

Elevated plasma fibronectin concentrations in patients with ossification of the posterior longitudinal ligament and ossification of the ligamentum flavum.

Fibronectin is a glycoprotein involved in a wide variety of cellular activities, including the development of bone tissues. To study the relevance of fibronectin to the development of ossification of the posterior longitudinal ligament (OPLL) and ossification of the ligamentum flavum (OLF), plasma fibronectin concentrations in 30 consecutive patients with OPLL or OLF and 20 age-and-sex-matched control subjects were measured with an immunonephelometric method. Plasma fibronectin concentrations were significantly elevated in the patients with OPLL or OLF, independently of associated endocrinologic abnormalities, when compared with the control subjects. Because fibronectin is one of the essential factors in endochondral ossification, it is probable that the higher fibronectin concentration in plasma acts as a promoter of the development of OPLL and OLF.

Neck and shoulder pain after laminoplasty. A noticeable complication.

STUDY DESIGN: The authors retrospectively analyzed the prevalence and features of neck and shoulder pain (axial symptoms) after anterior interbody fusion and laminoplasty in patients with cervical spondylotic myelopathy. OBJECTIVES: To reveal the difference in prevalence of postoperative axial symptoms between anterior interbody fusion and laminoplasty and to clarify the pathogenesis of axial symptoms after laminoplasty. SUMMARY OF BACKGROUND DATA: Outcome of the cervical surgery is evaluated on neurologic status alone; axial symptoms after laminoplasty rarely have been investigated. Such symptoms, however, are often severe enough to interfere with a person's daily activity. METHODS: Ninety-eight patients had surgery for their disability secondary to cervical spondylotic myelopathy. Of those patients, 72 had laminoplasty, and 26 had anterior interbody fusion. The presence or absence of axial symptoms was investigated before and after surgery. The duration, severity, and laterality of symptoms were also recorded. RESULTS: The prevalence of postoperative axial symptoms was significantly higher after laminoplasty than after anterior fusion (60% vs. 19%; P < 0.05). In 18 patients (25%) from the laminoplasty group, the chief complaints after surgery were related to axial symptoms for more than 3 months, whereas in the anterior fusion group, no patient reported having such severe pain after surgery. CONCLUSIONS: The prevalence and severity of axial symptoms after laminoplasty proved to be higher and more serious than has been believed. Such symptoms should be considered in the evaluation of the outcome of cervical spinal surgery.

Idiopathic spinal cord herniation: report of three cases and review of the literature.

STUDY DESIGN: Three case reports and a literature review are presented. OBJECTIVE: To describe characteristic clinical and radiographic findings of idiopathic spinal cord herniation. SUMMARY OF BACKGROUND DATA: Idiopathic spinal cord herniation is a rare disease, with only 26 cases reported before the current study. METHODS: Three cases of idiopathic spinal cord herniation are reported, and previous reports on this subject are reviewed. RESULTS: The responsible regions were in the thoracic spine from T2 to T7. Symptoms were mainly unilateral muscle atrophy in the lower extremity and sensory disturbance below the thoracic level. These symptoms had been progressing gradually. Magnetic resonance imaging demonstrated a unique feature: The spinal cord shifted anteriorly in a few segments. Computed tomographic myelogram showed another distinctive picture: There was no subarachnoid space anterior to the spinal cord. CONCLUSIONS: Because idiopathic spinal cord herniation is out of the concept of "compression myelopathy," this condition may be a pitfall in the diagnosis. Idiopathic spinal cord herniation should be recognized as one of the treatable causes for thoracic myelopathy.

Atlantoaxial rotatory fixation. Radiographic study of its mechanism.

The mechanism of atlantoaxial rotatory fixation was investigated by means of CT scanning. During the acute stage, there was a common rotatory displacement of the occiput and atlas complex in relation to the axis. As symptom subsided spontaneously or with treatment, the displacement was reduced and the occiput and atlas complex was in normal alignment with the axis. In a few cases where survey x-ray presented persistence of a typical displacement between C1/2, there was a persistent rotatory displacement of the atlas within the occiput-atlas-axis (C0-C1-C2) complex. Here, the occiput faced in nearly the same direction as the axis and the rest of the cervical spine. This meant an interlocking of the rotated atlas between C0 and C2. Either one of the lateral mass articulation of the rotated atlas was anteriorly dislocated and interlocked. Compensatory derotation of the occiput and a hypermobility of the C0/1 articulation, limited to younger children, presumably produced such a rotatory displacement of the atlas within the C0-C1-C2 complex. Restriction of rotation and a residual postural deformity resulted from unilateral dislocation of the lateral mass articulation between C1/2 and residual rotatory displacement between C0/2, respectively. Difficulty in reducing such a postural deformity can be attributed to the fact that any manipulative force often fails to unlock the atlas within C0-C1-C2 complex because of an excessive mobility between the C0/C1, and a ligamentocapsular contracture can be established in the lateral mass articulation of the interlocked atlas in an ignored case.

Cineradiographic motion analysis of atlantoaxial instability in os odontoideum.

Cineradiography was used to study six patients with os odontoideum. Atlantoaxial kinematics was analyzed with the relative motion of the atlas on the axis. In all cases, the tracing of the anterior arch was straight in the sagittal plane, whereas the posterior arch moved in two different configurations: straight and S-shaped. In cases of S-shaped configurations, the anterior translation occurred in the neutral position. Such translation could threaten the stability of the atlantoaxial complex fixed with posterior wiring because circumferential wires allow the laminas to rotate in the sagittal direction. In patients with os odontoideum, pathomechanics of the atlantoaxial joint should be examined with cineradiography in order biomechanically to determine the soundest fixation.

Post-traumatic syringomyelia.

STUDY DESIGN: This study retrospectively analyzed patients who developed post-traumatic syringomyelia secondary to spinal cord injury. OBJECTIVES: To identify an indicator that would predict the outcome of surgical treatment for post-traumatic syringomyelia. SUMMARY OF BACKGROUND DATA: Syrinx-subarachnoid shunting was chosen as a surgical treatment for post-traumatic syringomyelia. No previous study has been published concerning magnetic resonance imaging findings' ability to predict surgical results before surgery. METHODS: Nine patients diagnosed by magnetic resonance imaging with post-traumatic syringomyelia were the subjects of this study. The magnetic resonance imaging findings and surgical results were analyzed. RESULTS: Neurologic deterioration was found in five patients. Ascending dissociated sensory disturbances and motor weakness were noticed to occur characteristically above the level of the spinal cord injury. The other four patients complained of a slight worsening of numbness without displaying neurologic deterioration. The five patients with neurologic deterioration were treated with a syrinx-subarachnoid shunting. Two of the five patients experienced sustained neurologic improvement after a midline myelotomy, which allowed the fluid within the syrinx to spout out and cause the expanded spinal cord to collapse. This was called a "high-pressure syrinx." In these two patients, the preoperative magnetic resonance imaging demonstrated a positive flow-void sign. On the other hand, drainage of the syrinx in the three patients with a negative flow-void sign did not collapse the expanded spinal cord, and the surgical results were considered fair. This was called a "low-pressure syrinx." CONCLUSIONS: Post-traumatic syringomyelia was classified into two types. A preoperative distinction could be made based on the presence or absence of the flow-void sign on a T2-weighted magnetic resonance image.

Interobserver and intraobserver reliability of the japanese orthopaedic association scoring system for evaluation of cervical compression myelopathy.

STUDY DESIGN: The inter- and intraobserver reliabilities of an assessment scale for cervical compression myelopathy were examined statistically. This scoring system consists of seven categories: motor function of fingers, shoulder and elbow, and lower extremity; sensory function of upper extremity, trunk and lower extremity; and function of the bladder. It evaluates the severity of myelopathy by allocating points based on degree of dysfunction in each category. OBJECTIVES: To determine the inter- and intraobserver reliabilities of the revised scoring system (17 - 2 points) for cervical compression myelopathy proposed by the Japanese Orthopedic Association. SUMMARY OF BACKGROUND DATA: Several scales to assess clinical outcome from treatment of cervical compression myelopathy have been proposed. Most of these scales include items evaluated by observers. However, no system, including the Japanese Orthopedic Association scoring system, has yet been validated in terms of interobserver reliability. METHODS: From five different university hospitals, 10 spine surgery specialists, 10 orthopedic surgeons who had just passed the board examination of the Japanese Orthopedic Association, and 13 residents in the first or second year of orthopedic residency programs were chosen. The participants in this study were 29 patients with myelopathy secondary to ossification of the posterior longitudinal ligament selected from five participating university hospitals. Several surgeons interviewed each patient twice at intervals of 1 to 6 weeks. Inter- and intraobserver reliabilities of the total score for all categories were evaluated by the intraclass correlation coefficient. The extension of the kappa coefficient of Kraemer also was calculated for each category to assess reliability of multivariate categorical data. RESULTS: The interobserver reliability of the total score for the first interview (intraclass correlation coefficient = 0.813) and the intra- and interobserver reliabilities of the total score (intraclass correlation coefficient = 0.826) were high. The level of experience and the hospital slightly affected the reliability of the Japanese Orthopedic Association scoring system. The kappa values for intraobserver data generally were high in each category, whereas the kappa values for interobserver data were relatively low for the categories of shoulder-elbow motor function and lower extremity sensory function. CONCLUSIONS: The inter- and intraobserver reliabilities of the Japanese Orthopedic Association scoring system for cervical myelopathy were high, suggesting that this system is useful for assessment of cervical myelopathy in comparative studies of treatment.

Neurologic complications of surgery for cervical compression myelopathy.

Neurologic complications resulting from surgery for 384 cases of cervical myelopathy (cervical soft disc herniation, spondylosis, ossification of the posterior longitudinal ligament) were reviewed. Surgical procedures performed included 134 anterior interbody fusions (Cloward or Robinson-Smith technique), 70 subtotal corpectomies with strut bone graft, 85 laminectomies, and 95 laminoplasties. Twenty-one patients (5.5%) sustained neurologic deterioration related to surgery. The deterioration was classified into two types on the basis of the neurologic signs observed: deterioration of spinal cord function or of nerve root function. Manifestations of the former varied from weakness of the hand to tetraparesis. Paralysis of the deltoid and biceps brachii muscles was an exclusive feature of deterioration in the nerve root group. Causes of this paralysis included malalignment of the spine related to graft complications, and a tethering effect on the nerve root following major shifting of the spinal cord after decompression. The causes of deterioration of the cord function included spinal cord injury during surgery, malalignment of the spine associated with graft complication, and epidural hematoma.

Expansive laminoplasty for cervical radiculomyelopathy due to soft disc herniation.

STUDY DESIGN: A comparative study was performed in patients with cervical radiculomyelopathy due to soft disc herniation to compare surgical results of laminoplasty with anterior discectomy and arthrodesis. OBJECTIVES: To determine whether posterior decompression without discectomy can be selected for cervical myelopathy due to cervical soft disc herniation. SUMMARY OF BACKGROUND DATA: Anterior cervical discectomy and arthrodesis has had acceptable surgical results, but a significant number of complications have been reported, especially those related to bone grafting. METHODS: Sixteen patients who received expansive laminoplasty and 17 patients who received anterior arthrodesis were studied. The mean value of the anteroposterior diameter of the spinal canal was 12.4 mm in the former and 12.9 mm in the latter. The mean follow-up was 3.1 years in the laminoplasty group, and 8.8 years in the anterior arthrodesis group. There was no statistical difference between the two groups in prognostic factors believed to affect surgical results. Neurologic results were evaluated with postoperative scores and recovery rates by methods previously described, and assessed by the Japanese Orthopaedic Association scoring system. RESULTS: The difference between the two groups in the recovery rate and final Japanese Orthopaedic Association score was not statistically significant. Surgical complications were more frequent in the anterior arthrodesis group than in the laminoplasty group. Additional surgeries were performed in three cases (18%) in the anterior arthrodesis group: posterior wiring for delayed union and kyphotic deformity in two cases, and laminoplasty for deterioration of myelopathy in one case. Regression of herniated cervical disc after laminoplasty was confirmed by computed tomography or magnetic resonance imaging in six of eight cases (75%). CONCLUSIONS: When the incidence of complications and the possibility of regression of herniated disc are taken into consideration, expansive laminoplasty can be selected for radiculomyelopathy due to cervical disc herniation.

Distribution of the basic fibroblast growth factor and its receptor gene expression in normal and degenerated rat intervertebral discs.

STUDY DESIGN: Using a rat spondylosis model, the distributions of cells expressing the basic fibroblast growth factor and its receptor were investigated in normal and degenerated intervertebral discs. Cell-proliferating activity in degenerated discs was also assessed. OBJECTIVES: This study was conducted to determine whether basic fibroblast growth factor is related to intervertebral disc degeneration. SUMMARY OF BACKGROUND DATA: Basic fibroblast growth factor stimulates proliferation and matrix synthesis of cultured intervertebral disc cells. METHODS: Immunohistochemistry and in situ hybridization histochemistry were conducted to detect cells with basic fibroblast growth factor-like immunoreactivity and fibroblast growth factor receptor messenger RNA, respectively. Cell-proliferating activity was evaluated by AgNOR staining. RESULTS: In degenerated discs, round chondrocytes with basic fibroblast growth factor-like immunoreactivity and fibroblast growth factor receptor messenger RNA are scattered instead of spindle-shaped cells in the normal anulus (normal anular cells), which are devoid of basic fibroblast growth factor-like immunoreactivity and fibroblast growth factor receptor messenger RNA. The proliferating activity of these chondrocytes is suggested to exceed that of normal anular cells. CONCLUSION: Basic fibroblast growth factor is suggested to promote proliferation of chondrocytes in degenerated discs in an autocrine or paracrine manner. Basic fibroblast growth factor may be related to intervertebral disc degeneration as a proliferation-stimulating factor of chondrocytes that replace normal anular cells during disc degeneration.