Biomedical subjects

Chi-Chien Niu

Publications and source records attributed to Chi-Chien Niu.

27 records · Page 2Linked to original sources

PubMed2003

Polymethylmethacrylate cement dislodgment following percutaneous vertebroplasty: a case report.

STUDY DESIGN: A case report is presented. OBJECTIVES: To report a rare complication of delayed cement displacement following percutaneous vertebroplasty. SUMMARY OF BACKGROUND DATA: Although percutaneous vertebroplasty is considered a minimally invasive procedure, it may result in several complications. To our knowledge, this is the first report of delayed cement displacement after percutaneous vertebroplasty. METHODS: A 69-year-old man with T12 osteoporotic compression fracture received percutaneous vertebroplasty. One month after surgery, the patient complained of progressive severe back pain, and roentgenographic image revealed a breakdown of the anterior cortex of the T12 vertebral body with anterior displacement of the bone cement. RESULTS: The complication was solved by one stage anterior and posterior operation: thoracoabdominal approach with removal of the displaced cement and posterior instrumentation from T11 to L1. The severe back pain with associated weakness improved after surgery. CONCLUSIONS: This complication is rare and likely to occur in treatment of osteoporotic vertebral fracture with avascular necrosis and anterior cortical defect.

Aged↗

PubMed2003

Intracorporal bone grafting for vertebral compression fractures with intraosseous vacuum phenomenon.

From April 1998 to January 2000 we treated 14 patients with vertebral osteoporotic compression fractures and intraosseous vacuum phenomenon with intracorporal bone grafting using a mixture of autogenous bone graft and calcium sulfate and posterior instrumentation. The mixture was packed into the fractured vertebral body through two tunnels created in the pedicles. Eleven patients were followed for a minimum of 24 months. All vertebral bodies healed. There were no perioperative complications. The average vertebral height restoration was 31%. On the visual analogue scale, there was an improvement of average 37 clinical scores.

Aged↗

PubMed2003

Cervical degenerative disease at flexion-extension MR imaging: prediction criteria.

PURPOSE: To determine if there are any neutral-position imaging criteria that can help predict functional cord impingement at flexion-extension cervical magnetic resonance (MR) imaging. MATERIALS AND METHODS: Sixty-two patients with cervical degenerative disease were evaluated with regard to the dynamic changes of canal stenosis at flexion-extension MR imaging. Functional cord impingement was considered if the cord was impinged or more impinged after neck flexion or extension. Selection criteria for neutral-position MR imaging, such as cervical curvature, canal space, degenerative stage, intramedullary high signal intensity on T2-weighted images, and resting instability, were evaluated for their ability to predict functional cord impingement at flexion-extension MR imaging (Fisher exact test, logistic regression analysis). RESULTS: MR images in 19 (31%) of 62 patients showed functional cord impingement at extension MR imaging compared with images in two (3%) patients at flexion MR imaging. Statistically significant differences were found for the criteria cervical degeneration stage (P <.001) and spinal canal space (P =.037) for predicting functional cord impingement at extension MR imaging. In contrast, no significant differences were found among selection criteria for flexion MR imaging. Probabilities of functional cord impingement at extension MR imaging were calculated with different combinations of degenerative stages and canal spaces. Probability could increase to 79% if the patient had both stabilization degeneration (disk protrusion or osteophytic formation with hypertrophy of the ligamentum flavum) and C7 canal space of 10 mm or less. CONCLUSION: None of the selection criteria evaluated in this study has the ability to predict functional cord impingement at flexion MR imaging; however, prediction of impingement at extension MR imaging can increase from 31% to 79% if proper criteria are selected.

Adolescent↗

PubMed2002

Combined anterior and posterior surgeries in the treatment of spinal tuberculous spondylitis.

Methods for the treatment of tuberculous spondylitis still are controversial. The authors treated 32 consecutive patients with a two-stage surgical technique combined with antituberculous chemotherapy for 1 year. After anterior debridement, fusion with autogenous anterior iliac tricortical strut bone graft was done, and in a second stage, posterior instrumentation and fusion with autogenous posterior iliac corticocancellous bone graft was done 11 days (range, 4-22 days) later. Postoperatively, patients were encouraged to ambulate with brace protection as early as possible. Twenty-nine patients were followed up for a minimum of 2 years (median, 4.7 years; range, 2-10 years) of whom 28 patients achieved solid fusion (97%). All patients had improvement of back pain including the only patient with pseudarthrosis. Neurologic deficits completely recovered in 84% (16 of 19) of patients after 3 months. Kyphotic deformity improved in all 29 patients (34.6 degrees versus 17.3 degrees ) with the average correction angle of 17.3 degrees. Clinically, 27 patients had achieved a satisfactory outcome (93%). There were no evident surgical complications. The authors, therefore, recommend a two-stage surgical technique combined with antituberculous chemotherapy to treat patients with severe vertebral body destruction attributable to tuberculosis because of its high success rate and a low complication rate.

Adolescent↗

PubMed2002

Clinical outcomes of revision lumbar spinal surgery: 124 patients with a minimum of two years of follow-up.

BACKGROUND: Pertinent literature on revision lumbar spinal surgery has revealed a wide variation in success rates, ranging from 12% to 82%. In addition, a solid consensus has not yet been reached on its positive factors. We retrospectively reviewed 124 consecutive patients who underwent revision lumbar spinal surgery and investigated the factors that affected the outcomes of their surgery. METHODS: Revision lumbar spinal surgery was performed in 124 patients from January 1992 to December 1996, with an average follow-up of 37.6 months (range, 24-89 months). The various factors analyzed included age, gender, previous diagnosis, number of previous operations, period of pain-free interval, neurologic deficit, operative procedure, and fusion status. This analysis revealed the effect of each factor on the overall results. Radiographs were obtained, and patients were assessed during the final follow-up or by questionnaire. RESULTS: The success rate of revision lumbar spine surgery in this study was 83.9%. Successful outcomes were significantly associated with the spinal procedure with fusion and with union of the spinal fusion. Patients with defined mechanical instability had better results than did those with stenosis only. In addition, the complication rate for repeated lumbar spinal surgery was 9.6% and major complications attributed to poor results. CONCLUSION: This study reveals a high success rate of revision spinal surgery. We recommend performing spinal fusion, and achievement of solid fusion in repeated low back surgery is invaluable for patients with spinal instability. Targeting the specific pathology of failed back surgery syndrome is crucial in attaining satisfactory results with revision lumbar spinal surgery.

Adult↗

PubMedDate not supplied

Anterior cervical corpectomy and strut graft fusion using a different method.

BACKGROUND CONTEXT: Strut graft fusion after corpectomy is frequently indicated for certain pathologies in the cervical spine. The "key-hole" technique and "dove-tail" technique are the popular methods used to insert the strut graft at present. Segmental collapse secondary to seating of the graft on cancellous bone and cord injury from placement or dislodgement the graft are our concerns. Our method was designed to solve these possible problems without affecting the arthrodesis. PURPOSE: To evaluate the results of this method that allows the graft to seat on both the hard end plate and cancellous bone of the upper and lower contacting vertebrae in a easy and safe way after varying levels of corpectomy in the cervical spine. STUDY DESIGN: A retrospective clinical and radiographic study conducted by an independent observer was performed on 23 patients treated with this different strut grafting method after cervical corpectomy, with at least 2 years of follow-up. PATIENT SAMPLE: A total of 23 patients from 1983 to 1994 underwent fusion using our strut grafting method with fibular allograft packed with autogenous bone. No augmented internal instrumentation was used in all these patients. The patients with an incomplete record or less than 2 years of follow-up were excluded beforehand. OUTCOME MEASURES: Clinical outcome was assessed by a score based on three factors: neck pain, dependence on medicine and ability to return to work. The total score of these factors was seven. A score from 0 to 3 was defined as satisfactory, and a score from 4 to 7 was defined as unsatisfactory. The result of graft fusion, collapse of interbody height and loss of lordotic angle corrected by the graft were evaluated through the radiographic studies. METHODS: The operative technique creates a notch in the anterior cortex and end plate of the respective superior and inferior vertebraes. Cylinder allograft filled with autogenous cancellous bone was used as bone graft for all patients. The bone graft is cut with corresponding pegs at both ends. The graft is inserted into the corpectomy space with the pegs inserted into the notches and the remainder of the graft placed onto the preserved superior and inferior bony end plates. RESULTS: Twenty patients achieved successful fusion (87%). On average, the loss of anterior and posterior interbody height was 2.79 mm and 2.93 mm, respectively. The average loss of lordotic correction was 2.83 degrees. Eighty-three percent achieved satisfactory clinical outcomes. There were no neurologic injuries encountered during the operation. Partial graft dislodgment occurred in two patients (8.7%). CONCLUSIONS: This different method of strut grafting after cervical corpectomy has proven its safety and efficacy in its fusion and clinical results.

Adolescent↗

PubMedDate not supplied

Surgical treatment for giant cell tumor of the thoracolumbar spine.

BACKGROUND: Giant cell tumor (GCT) of the bone has historically been regarded as an extremely unpredictable bone tumor. The anatomical characteristics of spinal GCT still present challenges to surgeons. Controversy remains regarding the proper treatment of patients with grade III tumors. METHODS: Eleven patients with grade III GCT of the thoracolumbar spine were treated between 1992 and 2002 at a medical center by the authors. Three patients were initially treated at other institutions. Adjuvant radiotherapy was employed for local recurrence in these three patients. The other eight patients were initially treated with marginal excision. The site, size, and extent of each lesion dictated the surgical approach. RESULTS: Five patients had tumor recurrence. One patient, who received radiotherapy, had local relapse with malignant transformation and finally died due to disease-related complications. One patient had a recurrent tumor with multiple metastases throughout the lung. Neurological status, measured using the American Spinal Injury Association scale, of one patient was worse after undergoing the procedure than preoperatively and three patients showed improvement. The other seven patients were classified as with the same grade postoperatively. CONCLUSION: Wide excision of GCT of the thoracolumbar spine is difficult and there is a risk of neurological deficit and spinal instability. Meticulous marginal excision with associated reconstruction may obtain good local control and preserve functional spine. Early detection of recurrent GCT during intensive follow-up can allow for treatment using en bloc excision which has achieved favorable prognoses.

Adolescent↗

PubMedDate not supplied

Transforaminal epidural steroid injection for discectomy candidates: an outcome study with a minimum of two-year follow-up.

BACKGROUND: The efficacy of epidural steroid injection for sciatica due to herniated disc is controversial. This study evaluates the therapeutic effect of an alternative technique that uses a modified approach of epidural steroid injection for the above mentioned disease. The aim was to determine whether this procedure can reduce the need of surgery among discectomy candidates. METHODS: Twenty-one eligible patients who had suffered from sciatica with unilateral symptoms for 2 to 24 months received injections of betamethasone in combination with xylocaine. The treatment outcome was evaluated by direct questioning and examination using the JOA score (the criteria for low back pain syndrome of Japanese Orthopaedic Association) before the procedure and at the final follow-up visit. The final analysis comprised 19 patients with a minimum of 24-month follow-up. RESULTS: The overall JOA score increased significantly from 14.26 +/- 3.25 before injection to 23.38 +/- 4.46 after injection showing improvement. In terms of subcategories, the JOA score for sciatica increased significantly from 0.69 +/- 0.48 before infection to 2.13 +/- 0.72 after injection and the JOA score for daily activity increased significantly from 7.44 +/- 2.16 before injection to 12.19 +/- 2.23 after injection). In the end, three treated patients received surgical decompression for intractable recurrent pain. CONCLUSIONS: Transforaminal epidural steroid injection is a relatively simple, effective and low-risk alternative to surgical decompression for the treatment of lumbar disc herniation in selected cases. The procedure significantly alleviates the severity of sciatica due to a herniated disc and improves the patient's daily activity; this reduces the need for surgical decompression.

Adult↗

PubMedDate not supplied

Postoperative wound infection rates after posterior instrumented spinal surgery in diabetic patients.

BACKGROUND: Diabetes mellitus is thought to be a risk factor for surgical site infection. There have been no reports about the infection rate in diabetic patients who have undergone posterior spinal instrumented fusion. We present a retrospective analysis of infection rates after posterior spinal instrumented fusion in diabetic and non-diabetic patients. METHODS: Of 337 patients who underwent posterior spinal instrumented fusion between 1995 and 1997, 39 were diabetic. Plasma glucose concentration, body mass index, type of instrument, operation time, blood loss, hospital stay and complications were recorded. The pathogenic organism and treatments for infection were also described. RESULTS: The rate of wound infection in diabetic patients was 10.3% compared with 0.7% in non-diabetic patients (p = 0.003). Body mass index and preoperative blood sugar were also significantly different between the two groups (p = 0.02, p < 0.001). CONCLUSIONS: Patients with a diabetic history or preoperative hyperglycemia had a higher infection rate after posterior spinal instrumented fusion when compared with non-diabetic patients.

Adult↗