Takato Aihara

Intervertebral disc degeneration associated with lumbosacral transitional vertebrae : A clinical and anatomical study

We studied 52 patients, each with a lumbosacral transitional vertebra. Using MRI we found that the lumbar discs immediately above the transitional vertebra were significantly more degenerative and those between the transitional vertebrae and the sacrum were significantly less degenerative compared with discs at other levels. We also performed an anatomical study using 70 cadavers. We found that the iliolumbar ligament at the level immediately above the transitional vertebra was thinner and weaker than it was in cadavers without a lumbosacral transitional vertebra. Instability of the vertebral segment above the transitional vertebra because of a weak iliolumbar ligament could lead to subsequent disc degeneration which may occur earlier than at other disc levels. Some stability between the transitional vertebra and the sacrum could be preserved by the formation of either an articulation or by bony union between the vertebra and the sacrum through its transverse process. This may protect the disc from further degeneration in the long term.

Evaluation of low back pain using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire for lumbar spinal disease in a multicenter study: differences in scores based on age, sex, and type of disease

BackgroundThe Japanese Orthopaedic Association (JOA) has investigated the JOA Back Pain Evaluation Questionnaire (JOABPEQ) to evaluate several aspects of low back pain in patients. The score includes five categories (25 items) selected from the Roland Morris Disability Questionnaire and Short Form 36, and a visual analogue scale. Japanese physicians have recently used these scores to evaluate back pain; however, the efficacy has not been fully explored in large-scale studies. In the current study, we used the JOABPEQ to evaluate lumbar spinal disease in 555 patients (with lumbar disc herniation, lumbar spinal stenosis, and lumbar disc degeneration/spondylosis) in multiple spine centers and compared the results based on age, sex, and type of disease.MethodsA total of 555 patients who had low back or leg pain were selected in 22 hospitals in Chiba Prefecture. Spine surgeons diagnosed their disease type based on symptoms, physical examination, radiography images, and magnetic resonance imaging. In all, 486 patients were diagnosed with spinal stenosis (239 patients), disc degeneration/spondylosis (143 patients), or disc herniation (104 patients). The other 69 patients were diagnosed with spondylolysis (16 patients) or other diseases (53 patients). The pain score in all patients was evaluated using the JOABPEQ (from 0 to 100, with 0 indicating the worst pain).ResultsThe age of the patients was 56.1 ± 13.3 years (mean ± SD); the age of patients in the disc herniation and disc degeneration/spondylosis group was significantly lower than that in the spinal stenosis group. The average JOABPEQ scores in all patients were, for low back pain, 47.1; lumbar function, 53.6; walking ability, 54.8; social life function, 48.7; and mental health, 48.3. The low back pain score in men was significantly worse than that in women. In contrast, the mental health score in women was significantly higher than that in men. The low back pain score in patients <40 years old and the walking ability score in patients >65 years old were significantly lower than those scores in other patients. Based on the disease type, low back pain, lumbar function, social life function, and mental health scores for patients with disc herniation were significantly worse than for those with spinal stenosis.ConclusionJOABPEQ scores were evaluated for several lumbar diseases. The average of five categories of JOABPEQ scores in all patients was similarly distributed. However, the average scores in the five categories were significantly different depending on age, sex, and type of disease. Compared with prior mass data (baseline data on the observational cohort of the Spine Patient Outcomes Research Trial in the United States), many data were similar based on the type of disease in the current study. Furthermore, the JOABPEQ is easy to use compared with the SF-36. Hence, we concluded that the JOABPEQ could be used worldwide as a tool for evaluating low back pain.

Does the morphology of the iliolumbar ligament affect lumbosacral disc degeneration

Study Design. An anatomic study of the iliolumbar ligament was performed in association with lumbosacral disc degeneration. Objectives. To determine whether the morphology of the iliolumbar ligament contributes to lumbosacral disc degeneration. Summary of Background Data. There have been few reports concerning the clinical significance of the iliolumbar ligament. Methods. We dissected 25 male and 27 female cadavers and measured the length and cross-sectional area of the anterior and posterior bands of the iliolumbar ligament. The specimens were classified into three groups based on the grade of L4-L5 and L5-S1 disc degeneration: the L4-L5 disc was more degenerated than the L5-S1 disc (group L), the L4-L5 disc was less degenerated than the L5-S1 disc (group S), and both discs were equally degenerated (group E). The results were statistically compared among the three groups. Results. The length of the posterior bands and the summation of the length of the anterior and posterior bands were significantly shorter in group L than in group S, and the cross-sectional area of the posterior bands and the summation of the cross-sectional area of the anterior and posterior bands were significantly larger in group L than in groups S or E in the male cadaver specimens. Conclusion. If the iliolumbar ligaments (especially the posterior band of the ligament) of a male patient are short and have a large cross-sectional area, the lumbosacral junction can be stabilized by the ligaments, with the L5-S1 disc being protected from degeneration. The L4-L5 disc may be prone to degeneration.

Does the iliolumbar ligament prevent anterior displacement of the fifth lumbar vertebra with defects of the pars

We studied 23 patients with spondylolysis of the fifth lumbar vertebra (L5) and 20 with spondylolytic spondylolisthesis at this level. All were more than 40 years of age. The transverse processes at L5 were significantly wider in the former group than in the latter. We also dissected 56 cadavers to study the morphological relationship between the transverse process of L5 and the iliolumbar ligament, and found that the wider transverse process is associated with increased width of the posterior band of the iliolumbar ligament. If a patient with pars defects has wide transverse processes at L5, the lumbosacral junction may be stabilised by wide posterior bands of the iliolumbar ligament and the fifth lumbar vertebra by the ligament, preventing anterior displacement.

Fracture-dislocation of the fifth lumbar vertebra

We have studied fracture-dislocation of the fifth lumbar vertebra in seven patients and reviewed 50 previously reported cases. Based on this information, we have classified the injury into five types: type 1, unilateral lumbosacral facet-dislocation with or without facet fracture; type 2, bilateral lumbosacral facet-dislocation with or without facet fracture; type 3, unilateral lumbosacral facet-dislocation and contralateral lumbosacral facet fracture; type 4, dislocation of the body of L5 with bilateral fracture of the pars interarticularis; and type 5, dislocation of the body of L5 with fracture of the body and/or pedicle, with or without injury of the lamina and/or facet. Conservative treatment of fracture-dislocation of L5 is generally not effective because the lesion is fundamentally unstable. Planning of the operation should be made on the basis of the various types of injury.

SURGICAL MANAGEMENT OF DEGENERATIVE LUMBAR SPONDYLOLISTHESIS: A COMPARATIVE STUDY OF OUTCOMES FOLLOWING DECOMPRESSION WITH FUSION AND MICROENDOSCOPIC DECOMPRESSION

Fifty consecutive patients with degenerative lumbar spondylolisthesis were treated surgically. The first 17 patients (FU group) underwent decompression with fusion, the second 33 patients (MED group) underwent microendoscopic decompression (MED), and the outcomes following the two surgical methods were compared. The duration of follow-up ranged from 27 to 40 months in the FU group and from 25 to 40 months in the MED group. Clinical outcomes were evaluated with use of the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire. Although statistically not significant, the degrees of improvement in all five functional scores were greater in the MED group than in the FU group. There was no influence of instability before MED to the clinical outcome, and a large percentage of slipping in the neutral position could lead to inadequate improvement in low back pain after MED, but MED is a useful, minimally invasive operation and can lead to a good clinical outcome for degenerative lumbar spondylolisthe...

Incidence of Nocturnal Leg Cramps in Patients with Lumbar Spinal Stenosis before and after Conservative and Surgical Treatment

Purpose To examine the effects of conservative and surgical treatments for nocturnal leg cramps in patients with lumbar spinal stenosis (LSS). Nocturnal leg cramps is frequently observed in patients with peripheral neuropathy. However, there have been few reports on the relationship between nocturnal leg cramps and LSS, and it remains unknown whether conservative or surgical intervention has an impact on leg cramps in patients with LSS. Materials and Methods The subjects were 130 LSS patients with low back and leg pain. Conservative treatment such as exercise, medication, and epidural block was used in 66 patients and surgical treatment such as decompression or decompression and fusion was performed in 64 patients. Pain scores and frequency of nocturnal leg cramps were evaluated based on self-reported questionnaires completed before and 3 months after treatment. Results The severity of low back and leg pain was higher and the incidence of nocturnal leg cramps was significantly higher before treatment in the surgically treated group compared with the conservatively treated group. Pain scores improved in both groups after the intervention. The incidence of nocturnal leg cramps was significantly improved by surgical treatment (p=0.027), but not by conservative treatment (p=0.122). Conclusion The findings of this prospective study indicate that the prevalence of nocturnal leg cramps is associated with LSS and severity of symptoms. Pain symptoms were improved by conservative or surgical treatment, but only surgery improved nocturnal leg cramps in patients with LSS. Thus, these results indicate that the prevalence of nocturnal leg cramps is associated with spinal nerve compression by LSS.

Conservative and Surgical Treatment Improves Pain and Ankle-Brachial Index in Patients with Lumbar Spinal Stenosis

Purpose The pathological mechanism of lumbar spinal stenosis is reduced blood flow in nerve roots and degeneration of nerve roots. Exercise and prostaglandin E1 is used for patients with peripheral arterial disease to increase capillary flow around the main artery and improve symptoms; however, the ankle-brachial index (ABI), an estimation of blood flow in the main artery in the leg, does not change after treatment. Lumbar spinal nerve roots contain somatosensory, somatomotor, and unmyelinated autonomic nerves. Improved blood flow by medication with prostaglandin E1 and decompression surgery in these spinal nerve roots may improve the function of nerve fibers innervating muscle, capillary, and main vessels in the lower leg, resulting in an increased ABI. The purpose of the study was to examine whether these treatments can improve ABI. Materials and Methods One hundred and seven patients who received conservative treatment such as exercise and medication (n=56) or surgical treatment (n=51) were included. Low back pain and leg pain scores, walking distance, and ABI were measured before treatment and after 3 months of conservative treatment alone or surgical treatment followed by conservative treatment. Results Low back pain, leg pain, and walking distance significantly improved after both treatments (p<0.05). ABI significantly increased in each group (p<0.05). Conclusion This is the first investigation of changes in ABI after treatment in patients with lumbar spinal stenosis. Improvement of the spinal nerve roots by medication and decompression surgery may improve the supply of blood flow to the lower leg in patients with lumbar spinal stenosis.

Degenerative Lumbar Spondylolisthesis with Spinal Stenosis: A Comparative Study of 5-Year Outcomes Following Decompression with Fusion and Microendoscopic Decompression

Study Design Retrospective review of prospectively collected outcome data. Purpose To compare 5-year outcomes following decompression with fusion (FU) and microendoscopic decompression (MED) in patients with degenerative lumbar spondylolisthesis (DLS) and to define surgical indication limitations regarding the use of MED for this condition. Overview of Literature There have been no comparative studies on mid- or long-term outcomes following FU and MED for patients with DLS. Methods Forty-one consecutive patients with DLS were surgically treated. Sixteen patients first underwent FU (FU group), and 25 then underwent MED (MED group). The 5-year clinical outcomes following the two surgical methods were compared using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire. Results The degree of improvement (DOI) for social life function was significantly greater in the MED group than in the FU group. Although not statistically significant, DOIs for the other four functional scores were also greater in the MED group than in the FU group. However, patients with a large percentage of slippage in the neutral position might experience limited improvement in low back pain, those with a large percentage of slippage at maximal extension might experience limited improvement in three functional scores, and those with a small intervertebral angle at maximal flexion might have limited improvement in three functional scores after MED for DLS. Therefore, we statistically compared the DOIs between the FU and MED groups regarding the preoperative percentage of slippage in the neutral position among patients with greater than 20% slippage, the preoperative percentage of slippage at maximal extension among patients with greater than 15% slippage, and the intervertebral angle at flexion among patients with angles lesser than −5°; however, there were no statistically significant differences between the two groups. Conclusions MED is a useful minimally invasive surgical procedure that possibly offers better clinical outcomes than FU for DLS.