Bilateral phrenic nerve palsy as a complication of anterior decompression and fusion for cervical ossification of the posterior longitudinal ligament.

STUDY DESIGN: A case report of bilateral phrenic nerve palsy as a complication of anterior decompression and fusion for cervical ossification of the posterior longitudinal ligament (OPLL). OBJECTIVES: To present a case of a rare and serious complication of cervical spinal surgery and to investigate its cause. SUMMARY OF BACKGROUND DATA: There have been a number of reports of phrenic nerve palsy after cardiac surgery, but the authors have found no previous description of this complication related to spinal surgery. METHODS: The authors describe the clinical presentation and management of a case of bilateral phrenic nerve palsy subsequent to the surgery for cervical OPLL. Also, the literature is reviewed concerning surgical approaches for the treatment of OPLL and the occurrence of phrenic nerve palsy subsequent to any form of therapy. RESULTS: Bilateral phrenic nerve palsy occurred after anterior decompression and fusion for cervical OPLL. Bilateral phrenic nerve palsy was diagnosed radiographically: postoperative chest radiograph showed bilateral laxity of the diaphragm. Movement of the bilateral diaphragm appeared 3 weeks after surgery. The patient successfully returned to normal daily life after ventilatory support for 3 months, although nocturnal oxygen support was still necessary at the latest follow-up, 3 years after surgery. The possible causes of this complication include bilateral C4 nerve root stretching, iatrogenic injury of the gray matter in the ventral horn, alteration of blood circulation related to spinal edema, or re-impingement on the spinal cord at the cranial part of the decompression site. CONCLUSIONS: Bilateral phrenic nerve palsy occurred after anterior decompression and fusion for cervical OPLL. Bilateral phrenic nerve palsy should be kept in mind as a serious complication of spinal surgery. It should be considered when patients unexpectedly fail to wean from the ventilator after surgery.

Lumbar posterolateral fusion with biphasic calcium phosphate ceramic.

The authors conducted a retrospective observational study of patients who needed lumbar posterolateral fusion (PLF) using a biphasic calcium phosphate ceramic implant as a substitute for bone graft. The findings of clinical, radiographic, and histologic examinations were reviewed. Thirty-two patients underwent single-level PLF with instrumentation. In all cases, to decrease the occurrence of donor-site complications and morbidity, locally harvested morselized bone from the decompressive site was mixed with hydroxyapatite and beta-tricalcium phosphate (HAP-TCP) granules and sticks and used for fusion at the posterolateral aspect of the lumbar spine. The histologic findings of three biopsy specimens obtained during second operations for metallic implant removal were reviewed. The minimum follow-up period was 26 months. There was no evidence of instrument loosening or breakage. However, bone-graft incorporation was difficult to evaluate radiographically, because image quality was inferior to that with conventional autogenous iliac bone graft. Partial graft bone resorption was revealed on radiographs in 75% of cases. The results showed clinical improvement in all but one case. Solid fusion was observed during the second operation in all three cases. Histologic analysis showed excellent bone incorporation around the HAP-TCP granules. These findings suggest that, although the bulk of the fusion mass with HAP-TCP was smaller than that with autogenous bone, this technique combined with rigid instrumentation is a safe and effective procedure.

Arrayed silicon prism coupler for a terahertz-wave parametric oscillator.

Using room-temperature parametric oscillation of a LiNbO3 crystal pumped by a Q-switched Nd:YAG laser with a simple configuration, we have realized a widely tunable coherent terahertz- (THz-) wave source in the range between 1 and 3 THz. Inasmuch as the THz wave is affected by total internal reflection at the crystal edge, we used a Si prism coupler to couple out the THz wave. We introduce an arrayed Si-prism coupler that increases the efficiency and decreases the diffraction angle. By use of the arrayed-prism coupler, there is a sixfold increase in coupling efficiency and a 40% decrease in the far-field beam diameter, compared with the use of a single-prism coupler. We discuss the negative effect of the free carriers at the Si-prism surface that is excited by the scattered pump beam, and the positive effect of cavity rotation on the unidirectional radiation of the THz wave from a Si prism.

Missing anterior cervical plate and screws: a case report.

STUDY DESIGN: A case report of an anterior cervical plate and screws that disappeared completely. OBJECTIVES: To present a case of a missing anterior cervical plate and screws, this being quite a rare complication of a cervical implant. SUMMARY OF BACKGROUND DATA: No mention of this complication was found in the literature. METHODS: Methods in the literature and clinical presentation are reviewed. RESULTS: Dislodgment of an anterior cervical plate occurred in association with an methicillin-resistant Staphylococcus aureus infection. Three months later the implants had disappeared, presumably passing without notice through the gastrointestinal tract. Whole body fluoroscopy could not identify any residual plate or screws. No esophageal fistula could be detected by barium meal swallow study. CONCLUSIONS: The plate and screws became dislodged, eroded through the posterior wall of the esophagus, then traversed the limit of the gastrointestinal tract, passing with feces without significant morbidity. Whether the methicillin-resistant Staphylococcus aureus infection contributed to this unique circumstance or is coincidentally related to it remained a matter of speculation.

Enhancement of terahertz-wave output from LiNbO(3) optical parametric oscillators by cryogenic cooling.

In recent years widely tunable terahertz- (THz-) wave generation from LiNbO(3) optical parametric oscillators (OPO's) has been successfully demonstrated by use of the prism output-coupler method. However, there remains a problem of large absorption loss for generated terahertz waves inside the crystal, so we investigated the cryogenic characteristics of the OPO. We achieved 125-times-higher THz-wave output and 32% reduction of the generation threshold by cooling the crystal to 78 K. This scheme also provides direct loss measurement at THz frequency, and we found that the THz-wave enhancement mechanism is improvement of the gain as well as the reduction of the absorption coefficient.

Considerations for surgical treatment of patients with upper lumbar disc herniations.

Nine patients treated by surgery for upper lumbar disc herniations were reviewed. Of nine patients with upper lumbar disc herniations at the L1-L2 or L2-L3 level, five were treated by anterior procedures, whereas four underwent posterior procedures. Four of the five patients on whom anterior procedures were performed underwent additional spinal instrumentation using the Kaneda device and Z-plate system. Clinical symptoms improved in all nine patients. Confirmation of the type and level of disc herniation and increased thoracolumbar kyphosis must be taken into consideration when the optimal surgical procedure and spinal instrumentation method are selected.

Cervical myelo-radiculopathy in athetoid cerebral palsy.

Cervical myelopathy complicating athetoid cerebral palsy has not been adequately highlighted in the literature. We report two cases of patients with athetoid cerebral palsy and long histories of involuntary movements who developed cervical myelo-radiculopathy. Dystonic athetoid neck movements may cause excessive axial neck rotation as well as flexion and extension movements of the spine. These repetitive exaggerated movements may result in early degenerative changes of the vertebrae which may enhance the myelo-radiculopathy. The two patients were treated with combined anterior and posterior fusion with satisfactory results. They were bedridden preoperatively but have since started walking with or without a cane. We conclude that combined anterior and posterior fusion is the treatment of choice for severe myelopathy complicating athetoid cerebral palsy.

Chylous leakage after circumferential thoracolumbar fusion for correction of kyphosis resulting from fracture. Report of three cases.

STUDY DESIGN: A description of the clinical picture of chylous leakage after spinal surgery. OBJECTIVES: To present the clinical course of three cases of chylous leakage after spinal surgery and to discuss the pathogenesis of the disease. SUMMARY OF BACKGROUND DATA: Chylous leakage is a rare complication after spinal surgery. It has been attributed to direct injury of a lymphatic trunk or one of its major tributaries by surgical maneuver. METHODS: Three cases of chylous leakage after circumferential thoracolumbar fusion for correction of kyphosis resulting from fracture were reported. RESULTS: All of the three cases were managed successfully; two cases of chyloretroperitoneum detected within 4 days after surgery were healed conservatively, but one case of chylothorax of which the onset was noticed 5 weeks after spinal surgery, required surgical ligation of the thoracic duct and pleurodesis. CONCLUSION: Early detection of this disease is important for a good prognosis. Retroperitoneal drainage is necessary for the detection and management of chyloretroperitoneum. The pathogenesis and management of the chylous leakage are discussed in this report.

Suction/irrigation for deep wound infection after spinal instrumentation: a case study.

Deep wound infection after spinal instrumentation is a serious complication that is difficult to treat without removing the instruments and bone graft. Debridement and suction/irrigation is an effective method of treatment in these cases. It was performed on six patients in our department who developed this complication between 1985 and 1994. Four patients with early post-operative infection were cured by this method without removing the instruments and bone graft, and two patients with delayed post-operative infection were cured by this method with instrument removal. Debridement and suction/irrigation is a useful method of treatment for both groups of deep wound infection and gives good results when performed soon after infection onset together with additional antibiotic therapy.

Anterior decompression and fusion for ossification of posterior longitudinal ligament in the thoracic spine.

Twelve cases are reviewed of ossification of posterior longitudinal ligament (OPLL) in the thoracic spine for which anterior decompression and fusion were performed. A transthoracic approach was used in 10 patients, and median sternotomy and a transsternal approach were used in one each. The clinical symptoms and the Japanese Orthopaedic Association (JOA) score improved in 10 patients, whereas they were unchanged in two patients who underwent a revision operation for a previous laminectomy. An anterior procedure that results in adequate decompression of the spinal cord and good spinal stability is recommended for anterior lesions, such as OPLL, which compress the anterior spinal cord at each level of the thoracic spine.

Progressive scoliosis associated with lateral gaze palsy.

Two cases with progressive scoliosis and lateral gaze palsy were reported. The preoculomotor centers, which are connected by the fasciculus longitudinalis medialis in the brain stem, are deemed to be the common focus for progressive scoliosis and associated visual dysfunction.

Villous component as a marker for synchronous and metachronous colorectal adenomas.

To determine whether patients with colorectal adenomas containing a villous component (+vc group) have a higher incidence of synchronous or metachronous colorectal adenomas, 527 consecutive cases of completely removed colorectal adenoma were used. Synchronous adenomas were detected in 22.6 percent and 19.0 percent of the patients in the +vc and -vc groups, respectively. In the analysis of metachronous adenomas, 164 patients who had been followed for 1 to 11 years (mean, 3.31 years) were included. The cumulative adenoma-free rate according to Kaplan-Meier tended to be lower in the +vc group, the difference being statistically significant 1.0 to 1.2 years after treatment of the initial adenoma and the two curves being different based on the generalized Wilcoxon test. The numbers of newly detected adenomas annually were 1.76 and 0.86, and their annual incidences were 1.09 and 0.59 times, in the +vc and -vc groups, respectively. These results suggest the importance of the villous component as a predictor of metachronous colorectal adenomas.

Posterior decompression and stabilization for multiple metastatic tumors of the spine.

Although the value of surgical decompression and stabilization for solitary spinal metastasis is well documented, indication for surgery for advanced multiple metastatic tumors of the spine is controversial. In this study, the clinical effect of posterior decompression and stabilization was investigated in 11 patients with advanced multiple spinal metastases with unfavorable conditions. Mean blood loss during surgery was 3000 g. Disseminated intravascular coagulation occurred in three patients. Neurologic improvement was observed in nine patients. There was no neurologic deterioration due to surgery in any patients. A measure of pain relief was obtained in all patients. However, the postoperative longevity was short and the patients died 2.5 months (on average) after operation, except in cases of breast cancer. The effect of the posterior surgery on multiple spinal metastases depended on primary diseases. In cases of short life expectancy, the effect of the surgery was limited only to the short duration of neurologic improvement, pain relief, and ease of nursing care while confronted with grave surgical morbidity. In cases of long life expectancy with tumors like breast cancer, however, posterior decompression and stabilization were expected to exert long-term therapeutic effect. Therefore, the posterior surgery for multiple spinal metastases is cautiously indicated considering the nature of the primary tumor.

[Decision analysis in therapeutic strategies for small bowel obstructions].

Clinical decision analysis was applied in therapeutic decision-making regarding small bowel obstructions. For strangulation obstruction, the three strategies of immediate surgery, observation of clinical course, and decision according to ultrasonographic findings were analyzed. When mortality rate, morbidity rate, or duration of hospital stay was used as the utility value, decision on the basis of ultrasonographic findings was selected as the most effective strategy, while the strategy of immediate surgery was selected when the rate of intestinal necrosis was used as the utility value. For adhesive obstructions, the three strategies of immediate surgery, conservative treatment with long tube decompression, and long tube decompression with enteroclysis (infusion contrast radiography) were analyzed. The strategy of enteroclysis was selected when morbidity rate and duration of hospital stay were used as utility values, while immediate surgery was selected when recurrence rate of adhesive obstruction was used as the utility value. For obstruction caused by intraabdominal recurrent cancer, operative treatment and conservative treatment were analyzed. The strategy of surgery was selected when rate of obstruction resolved and number of months of survival were used as utility values. Clinical decision analysis is valuable in quantitatively assessing individual variables affecting therapeutic decision-making.

Relationship of cholecystectomy and detachment of the common bile duct to chronic bile duct dilation.

A combination of a cholecystectomy and detachment of the supportive tissue surrounding the extrahepatic bile duct results in chronic bile duct dilation. To clarify whether this cholangiectasis is due to the detachment of the surrounding tissue or to the cholecystectomy, we have studied 4 groups of adult mongrel dogs, i.e., a control group given a sham operation (n = 20), a group given cholecystectomy (n = 20), a group that had the surrounding tissue detached from the bile duct (n = 20), and a group given both a cholecystectomy and detachment of the surrounding tissue (n = 29). On examination by cholangiography at 1, 2, 3, and 4 weeks after the initial laparotomy, no significant cholangiectasis was found in dogs subjected to either cholecystectomy alone or to detachment of the surrounding tissue alone. In contrast, in dogs subjected to a cholecystectomy combined with detachment of the bile duct, the bile duct gradually dilated, resulting in significant cholangiectasis at 4 weeks. However, the intrabiliary pressure, the residual pressure, and the actual resistance value, which are indices of a passage disturbance in the sphincter of Oddi, were normal in all 4 groups. It is therefore concluded that both the extirpation of the gallbladder, and the lack of supportive tissue surrounding the bile duct were responsible for the resulting cholangiectasis.

Extensive en bloc resection of regionally recurrent carcinoma of the rectum.

To remove regionally recurrent cancer of the rectum completely, more radical extensive resections were attempted than the conventional ones in 35 patients. Twenty-two patients underwent total pelvic exenteration. In 23, sacral resection was done, combined with other procedures including excision of the entire circumference of the lower pelvic ring. There were two hospital deaths. Delayed wound healing was seen in ten. Preoperative severe pain was alleviated in 18. Also, perineal ulcer, vaginal bleeding, bloody stools, and tenesmus disappeared. Of the four 5-year survivors (estimated rate, 23%), only one was disease-free. A second recurrence was seen in 27 patients, of whom 23 had regional failure. It was concluded that so-called local recurrence is a lesion more widespread than indicated by imaging and biopsy. Therefore, even the most radical resection rarely can cure this disease. However, such a surgical procedure can afford more effective palliation than other treatments and may prolong life in selected patients significantly.

Surgical treatment of giant-cell tumors of the spine.

Three cases of relatively uncommon giant-cell tumors in the third cervical and first thoracic vertebra and the sacrum were treated surgically by radical resection and reconstruction. The tumor in the third cervical vertebra was treated by incomplete excision and anterior arthrodesis at a local hospital without pre- or postoperative radiotherapy. A recurrence was noted after four months, however, and an emergency operation was performed for severe quadriplegia. After posterior decompression, the tumor was resected by the lateral approach, and an autograft was performed. The tumor in the first thoracic vertebra was removed simultaneously by the anterior, posterior, and lateral approaches, and reconstruction was performed. The sacral tumor, which was radioresistant, was totally excised, and reconstruction was performed. Using these treatments, excellent results have been recorded after follow-up intervals of 1.5, three, and six years. Because of advancements in preoperative imaging techniques and better surgical techniques, radical resection is the recommended treatment for giant-cell tumors located in the spine.

Bone-fibrin mixture in spinal surgery.

When bone grafting is performed adjacent to the spinal cord, instability of the grafted bone can result in compression of the spinal cord. To prevent this complication, fibrin sealant was mixed with the fine fragments of autogeneic bone, and the resultant pastelike mixture was used as a graft material. Operative procedures performed were posterolateral fusion (11 cases), anterior fusion (seven cases), and grafting into the bone defect (one case). After solidification of fibrin sealant, the autogeneic bone grafts were found to be firmly fixed in place, resulting in good bony fusion, and there were none of the neurologic symptoms associated with graft instability. No neurotoxicity was observed in any of these patients. Fibrin sealant was found to be an effective material for spinal surgery.