Tetsuhiro Iguchi

Minimum 10-year outcome of decompressive laminectomy for degenerative lumbar spinal stenosis

Study Design. A retrospective follow-up study was conducted in patients who underwent decompressive laminectomy for degenerative lumbar spinal stenosis. Objectives. To describe the long-term outcome of decompressive laminectomy performed for degenerative lumbar spinal stenosis, and to investigate preoperative factors that influenced outcomes, especially risk factors predisposing patients to poor results. Summary of Background Data. The success rate of surgical treatment of decompressive laminectomy for lumbar spinal stenosis varies. Long-term follow-up investigations have indicated deterioration of outcome; however, the causes of deterioration have not been fully investigated, and there have been no reports with a minimum 10-year follow-up. Methods. Of 151 patients who underwent decompressive laminectomy from 1980 through 1989, 37 were followed up for a minimum of 10 years. The mean age at surgery was 60.9 ± 8.2 years (range, 43–76), and the average follow-up period was 13.1 ± 2.1 years (range, 10.1–17.4). The results were evaluated by the criteria of the Japanese Orthopedic Association Lumbar Score, and the outcome was classified as excellent at more than 75% improved score; good, 50–75%; fair, 25–49%; and poor, 0–24% or less. Information about impairment of activities of daily living was also obtained at follow-up. Associations between preoperative clinical and radiographic variables and clinical outcome were evaluated statistically. Results. In all patients, the average score improvement of 55.2 ± 31.6% was regarded as acceptable. The postoperative score and percentage of improvement of low back pain were lower than those of leg pain and walking ability. No impairment in activities of daily living was found in 62.2% of the patients. Rate of improvement was evaluated as excellent in 13 (35.1%), good in 8 (21.6%), fair in 8, and poor in 8 patients. Three patients required additional surgery because of disc herniation at the laminectomied segments. The patients with multiple laminectomy (P = 0.034) andmore than 10° preoperative sagittal rotation angle (P = 0.018) showed a significantly poorer outcome than the remainder of the patients. Conclusions. Long-term follow-up showed that even without spinal fusion, more than half the patients were evaluated as excellent or good. Patients with more than a 10° sagittalrotation angle who need multiple laminectomy, should be given information about the possibility of earlier deterioration of the outcome, and alternative oradditional treatment such as concomitant spinal fusionwith decompression may be considered.

Total sacrectomy and reconstruction for sacral tumors.

Study Design. Report of three patients in whom the lumbosacral junctions were successfully restored by spinal instrumentations after total sacrectomies. Objectives. To describe the surgical technique of the reconstruction of the continuity between the pelvic ring and spinal column by using a transpedicular and iliac screw system. Summary of Background Data. Although there have been case reports about reconstruction methods after total sacrectomy, biomechanical, and technical problems still remain unresolved. Methods. Total sacrectomy was carried out in three cases: two with chordomas and one with a recurrent giant cell tumor. In the first case, reconstruction was achieved with Zielke transpedicular screw and rod system and a sacral rod. The other two patients were reconstructed using a transpedicular and iliac screw system and a sacral rod for bilateral fixation of the iliac wings. In the third patient, the vertical rods were connected to transverse rod with rod connectors. Results. No instrumentation failure was observed, and the continuity between the pelvic wing and spinal column was established with the instrumentation and bone grafting. Although one patient died of metastatic chordoma, the lumbosacral junction was successfully reconstructed with the instrumentation. The other two patients could stand with double crutches 13 and 2 years after surgery, respectively. Conclusions. Total sacrectomy is a feasible operation for primary malignant tumors involving the entire sacrum. Reconstruction of the union between the lumbar spine and the ilia with spinal instrumentation achieves stabilization suitable for ambulation.

Lumbar multilevel degenerative spondylolisthesis: radiological evaluation and factors related to anterolisthesis and retrolisthesis.

Radiographs of 3,259 outpatients with low back disorders were examined for age, gender, level, direction, degree of slip, lumbar lordosis, pedicle–facet (P-F) angle, facet shape, and disc height. Degenerative lumbar spondylolisthesis was found in 284 (8.7%) of the patients, of which 83 were excluded. Single-level spondylolisthesis was present in 132 of the 201 patients studied, including 93 cases of anterolisthesis and 39 of retrolisthesis, the former being predominant at L4 and in women and the latter at L2 and equal between the genders. Multilevel spondylolisthesis in 69 patients included 65 (94%) of two-segment slip, 21 anterior, 25 posterior, and 19 combined, and 4 cases of three-segment retrolisthesis. Factors related to anterolisthesis were increased P-F angle and W-shaped facet joint; statistically, however, no factors were found statistically related to retrolisthesis. Multilevel anterolisthesis was considered to occur from factors similar to those previously reported for single-level anterolisthesis, and the pathomechanism of retrolisthesis is different from that of anterolisthesis.

Age distribution of three radiologic factors for lumbar instability: probable aging process of the instability with disc degeneration.

Study Design. Cross-sectional study of 880 outpatients with low back and/or leg pain regarding age distribution of three radiologic factors. Objectives. To investigate the proportion and relationship of three individual radiologic factors with age on segmental instability in sagittal plane in consecutive age groups. Summary of Background Data. Previous studies revealed relationships between radiologic factors for instability and symptoms; however, little is known about the relationship between factors and age except in degenerative spondylolisthesis. Methods. Excessive segmental motion, defined as more than 10° angulation, more than 3 mm translation, and more than 3 mm slip in neutral position, at the L4–L5 segment in 880 outpatients (389 men, 491 women) with low back and/or leg pain aged from 14 to 84 years was investigated by 3 observers. The number and rate of the patients with each excessive motion were evaluated in continuous age groups of 5 years. Results. The mean ages of patients with excessive angulation, translation, and slip in neutral position were 41.7, 50.0, and 62.8 years, respectively. Both rates of excessive angulation and translation showed two peak patterns demonstrating peaks in the teens and 20s groups and in the over 46 age groups; however, angulation was predominant in younger age groups and translation was predominant in older age groups. Slip in neutral position was frequently observed in age groups over 46 and increased with age. Conclusions. The presence of patients with excessive angulation and translation in younger age groups suggests they have a hypermobile segment with least degenerated discs. Different predominant patterns of these radiologic factors may reveal the probable aging process of the instability.

Delayed dural laceration by hydroxyapatite spacer causing tetraparesis following double-door laminoplasty.

OBJECT The authors describe 4 cases of delayed dural laceration by hydroxyapatite (HA) spacer causing tetra-paresis following double-door laminoplasty. There are few reports of iatrogenic spinal cord lesions developing after double-door laminoplasty, although some complications such as postoperative C-5 paralysis or axial symptoms have been reported. The purpose of this report is to draw attention to the possibility of delayed dural laceration and its triggering mechanism. METHODS One hundred thirty patients treated for cervical myelopathy were followed up for an average of 2 years and 9 months after laminoplasty. RESULTS Four patients experienced aggravation of cervical myelopathy. Anterior dislodgement of HA spacers was shown on plain lateral radiographs. Follow-up T2-weighted magnetic resonance imaging demonstrated that the dislodged HA spacers were surrounded by cerebrospinal fluid at the time of aggravation. The dislodged HA spacers were removed and the dural membrane defects were repaired by patching with the fascia of the gluteus maximus muscle. The preoperative symptoms improved after the second operation in all patients. CONCLUSIONS It is hypothesized that the loosening of the HA spacer in split spinous processes could occur with the movement of the cervical spine and/or the breakage of the suture before bone bonding. Anterior dislodgement of the HA spacer toward the spinal canal would cause dural laceration by direct friction between the dural membrane and the dislodged HA spacer, resulting in clinical aggravation. Despite the well-documented advantages of using HA spacers for double-door laminoplasty, possible laceration due to a dislodged HA spacer should be considered as a late complication.

Symptomatic hematoma of lumbar facet joint: joint apoplexy of the spine?

Study Design. A case report. Objectives. To report and discuss a rare case of epidural hematoma that was considered to be formed as a result of idiopathic bleeding occurring at the facet joint (joint apoplexy). Summary of the Background Data. Spontaneous spinal epidural hematoma is a relatively rare condition. According to a review article of 199 spontaneous spinal epidural hematomas in the last 2 decades, the majority of these conditions are thought to result from a rupture of the epidural vascular network. Recently, a hemorrhagic lumbar synovial cyst and a hematoma occurring from the ligamentum flavum were reported as rare types of epidural hematoma. Methods. The authors describe the treatment and the clinical, radiologic, surgical, and pathologic findings in one patient with a rare epidural hematoma. Results. Magnetic resonance imaging revealed that the extradural mass lesion was continuous with the right L4-5 facet joint; this was confirmed by surgery when the extradural hematoma was directly visualized. The joint cavity was also filled with the hematoma. There was no evidence of preceding cyst formation macroscopically or microscopically. The excised capsule of the left L4-5 facet joint revealed moderate hyperplasia of the synovium with an increased number of capillary vessels. Conclusions. This is the first reported case of radiculopathy considered to be a result of facet joint apoplexy in the absence of any preceding synovial cyst formation. The pathomechanism of the hemorrhage at the lumbar facet joint is unclear, but it is speculated that there could be an association with degenerative change of the facet joint. Surgical excision of this mass was considered to be the definitive treatment.

Satisfactory results at 8 years mean follow-up after ADVANCE® medial-pivot total knee arthroplasty.

BACKGROUND Although good overall results have been reported with TKA, certain problems and limitations remain, primarily due to postoperative differences in joint kinematics, when compared with the normal knee. ADVANCE® Medial-Pivot TKA involves replicating the medial pivoting behavior observed in normal knees. Here, we aimed to investigate the clinical and radiological results and complications of TKA using this implant, at mid-term follow-up. METHODS From January 2001 to March 2012, we retrospectively selected 76 patients (85 knees; mean age at operation, 70.2±8.1 years; range, 51-88 years) with a mean follow-up period of 93.1±14.3 months (range, 72-132 months). Indications for TKA included primary degenerative osteoarthritis (60 knees), rheumatoid arthritis (22 knees), osteonecrosis (two knees), and osteoarthritis following high tibial osteotomy (one knee). The clinical and radiographic results were evaluated. RESULTS Kaplan-Meier survivorship analysis indicated a success rate of 98.3% (95% confidence interval, 96.6-99.9%). Comparison of pre- and postoperative knee extension angles and ranges of motion showed significant improvement postoperatively, in both the Knee Society Scores (KSS) and Knee Society Functional Scores (KSFS) (p<0.05). In one case, radiographic assessment indicated implant loosening due to infection; however, despite this complication, significant improvement of postoperative varus or valgus deformity angles were noted in all cases (p<0.05). CONCLUSION Patients undergoing ADVANCE® Medial-Pivot TKA achieved excellent clinical and radiographic results without any implant-related failures at mid-term follow-up. LEVEL OF EVIDENCE Level IV.

The influence of sagittal instability factors on clinical lumbar spinal symptoms.

Study Design Cross-sectional and prospective study. Objective To find the critical order of 3 radiographic factors observed in standing flexion-extension films and to discover their combined effect on lumbar symptoms. Summary of Background Data Many previous reports have described relationships between degenerative change in the lumbar disc and segmental instability; however, few reports have attempted to show any relationship between instability and symptoms. Little is known about which type of instability is the most critical in the sagittal plane of the lumbar spine. Methods Excessive segmental motion (factors): >3 mm slip, >3 mm translation, and >10 degrees angulation, at the L4/5 segment in 880 patients (389 men and 491 women; mean age, 49.4 y) with low back and/or leg pain were investigated at initial visit. Symptoms of low back and leg pain, and walking ability were evaluated at initial visit and 4.6-year follow-up using Japanese Orthopaedic Associations scoring system. Severity and continuity of symptoms were evaluated and compared among the groups according to various combinations of excessive motion. Results Of the 3 factors, patients with >3 mm slip had the lowest scores, and patients with >10 degrees angulation had the highest, both at initial visit and follow-up (P<0.001). In the comparative study of various factors, the groups with >3 mm slip had significantly lower scores than the group with no factors, and these groups had significantly lower scores in leg pain and walking ability than the nonfactor group (P<0.05). Conclusions Of the 3 factors, >3 mm slip had the strongest effect on symptoms followed by >3 mm translation and then >10 degrees angulation. Therefore, patients with low back and/or leg pain at initial visit and >3 mm slip, may expect symptoms of a duration exceeding 4 years. More than 10 degrees angulation had the least effect on symptoms as shown by the similarity in scores with the nonfactor group.

Radiculopathy due to ossification of the yellow ligament at the lower lumbar spine.

Study Design. A case report. Objectives. To report a rare case of a 27-year-old female with ossification of yellow ligament at the lower lumbar spine presenting radiculopathy with a drop foot. Summary of Background Data. The majority of cases of ossification of yellow ligament occur at the lower third of the thoracic or the thoracolumbar spine. There are only a few reports of ossification of yellow ligament in the lumbar spine and radiculopathy due to ossification of yellow ligament at L4–L5 and L5–S1 levels is very uncommon. Methods. A 27-year-old female with a prior fracture of posterior ring apophysis of L5 presented with leg pain and a drop foot. Magnetic resonance imaging demonstrated stenosis with compression of the cauda equina at the L4–L5 and L5–S1 levels. Results. Decompressive laminectomy of L5 and removal of the ossified yellow ligaments were performed. Histologic examination of en bloc specimen of ossification of yellow ligament revealed degenerative changes of the elastic fibers in the yellow ligament with adjacent chondrosis and ossification. The patient’s severe leg pain disappeared completely, although the extent of the drop foot had not fully recovered at the final follow-up examination. Conclusions. The mechanism of ossification of yellow ligament in the present case was unclear. The patient did not have any previous generalized disorders besides the history of a ring apophysial fracture or any family history of treatment for ossification of the posterior longitudinal ligament or ossification of yellow ligament. Therefore, localized mechanical stress might have influenced the development of ossification of yellow ligament at lower lumbar spine. Spine 2003;28:E401–E404

Extension injury of the thoracolumbar spine.

Study Design. This is a report of a patient with a rare fracture in the thoracolumbar spine. Objectives. To illustrate the previously undescribed fracture in the thoracolumbar spine and to propose a new mechanism of this rare lesion with a literature review. Summary of Background Data. Extension injury of the thoracolumbar spine is uncommon. Although there have been several reports of hyperextension injuries in the thoracolumbar spine, the injury mechanism of the present case was different from those in the previously reported cases. Methods. The clinical findings, roentgenographic appearance, treatment, and follow-up result were presented, and the mechanism of this lesion was analyzed. Results. Physical examination revealed no neurologic deficit. Radiographs showed the oblique fracture line extended from the middle region of the L1-L2 disc to the posteroinferior edge of the L2 vertebral body, with the widening of bilateral L2-L3 facet joints. The patient was treated conservatively with a successful outcome. Two years after his injury, the patient had resumed his previous activity completely. Conclusions. The authors considered that the mechanism of this rare injury was a combination of hyperextension force and axial loading.