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Jeffrey C Wang

Publications and source records attributed to Jeffrey C Wang.

At least 19 recordsLinked to original sources
PubMed2007

A comparison of commercially available demineralized bone matrix for spinal fusion.

In an effort to augment the available grafting material as well as to increase spinal fusion rates, the utilization of a demineralized bone matrix (DBM) as a graft extender or replacement is common. There are several commercially available DBM substances available for use in spinal surgery, each with different amounts of DBM containing osteoinductive proteins. Each product may have different osteoinductivity potential due to different methods of preparation, storage, and donor specifications. The purpose of this study is to prospectively compare the osteoinductive potential of three different commercially available DBM substances in an athymic rodent spinal fusion model and to discuss the reasons of the variability in osteoinductivity. A posterolateral fusion was performed in 72 mature athymic nude female rats. Three groups of 18 rats were implanted with 1 of 3 DBMs (Osteofil, Grafton, and Dynagraft). A fourth group was implanted with rodent autogenous iliac crest bone graft. The rats were sacrificed at 2, 4, 6, and 8 weeks. A dose of 0.3 cm(3) per side (0.6 cm(3)per animal) was used for each substance. Radiographs were taken at 2 weeks intervals until sacrifice. Fusion was determined by radiographs, manual palpation, and histological analysis. The Osteofil substance had the highest overall fusion rate (14/18), and the highest early 4 weeks fusion rate of (4/5). Grafton produced slightly lower fusion rates of (11/17) overall, and lower early 4 weeks fusion rate of (2/5). There was no statistically significant difference between the rate of fusion after implantation of Osteofil and Grafton. None of the sites implanted with Dynagraft fused at any time point (0/17), and there was a significantly lower fusion rate between the Dynagraft and the other two substances at the six-week-time point and for final fusion rate (P = 0.0001, Fischer's exact test). None of the autogenous iliac crest animals fused at any time point. Non-decalcified histology confirmed the presence of a pseudarthrosis or the presence of a solid fusion, and the results were highly correlated with the manual testing. Although all products claim to have significant osteoinductive capabilities, this study demonstrates that there are significant differences between some of the tested products.

Animals↗
PubMed2007

Surgery for neck pain.

Axial neck pain is a common finding that typically represents a spectrum of clinical Arlington Orthopedic Associates, disorders affecting the cervical spine. Controversy exists concerning the ultimate treatment of the patient who presents with cervical spondylosis and primarily axial neck pain without radicular symptoms or myelopathy and who has failed to respond to extensive nonoperative treatment methods. Cervical discography has been used to assist in determining the specific level or levels causing the neck pain and, potentially, which levels to fuse; however, controversy regarding the specificity of cervical discograms has also been debated in the literature. Los Angeles, California We recommend exhausting all conservative means of treatment of axial neck pain. Surgery is offered only after conservative treatment fails and appropriate psychological testing is performed, as well as diagnostic imaging and discography that confirm a specific level or levels as the pain source. Cervical fusion may demonstrate good results in appropriately chosen patients with cervical spondylosis and axial neck pain.

Cervical Vertebrae↗
PubMed2006

The osteoinductive properties of Nell-1 in a rat spinal fusion model.

BACKGROUND CONTEXT: Recombinant growth factors bone morphogenetic protein-2 (BMP-2) and BMP-7 are currently approved for human use but are associated with various adverse effects including ectopic bone formation and local inflammatory reaction. The development of alternative growth factors may help minimize the adverse effects of current osteoinductive therapeutics. Nell-1 (Nel-like molecule-1; Nel [a protein strongly expressed in neural tissue encoding epidermal growth factor like domain]) is a novel secretory molecule that appears to act more specifically on osteoblasts than the BMPs, which can act on multiple cell types. From a molecular point of view, Nell-1 is directly regulated by runt-related transcription factor 2 (Runx2/Cbfa1), a master regulatory gene controlling bone formation. Previous studies showed that Nell-1 accelerates osteogenic differentiation in vitro and calvarial bone formation in vivo. We hypothesize that Nell-1 may also effectively form bone in spinal fusion. PURPOSE: Our primary aim was to assess if direct adenoviral gene delivery with Nell-1 in a demineralized bone matrix (DBM) carrier can improve spinal fusion in a rat model. Because adenoviral vectors allow for sustained growth factor delivery, they were used for initial feasibility testing before protein studies. STUDY DESIGN/SETTING: Two groups of 20 athymic rats underwent posterolateral intertransverse process spinal fusion at L4-L5 with implanted DBM carrier containing either adenovirus coding for Nell-1 (AdNell-1) or control, Lac Z (AdLacZ). No cells were implanted. The 20 rats were sacrificed at 6 weeks for evaluation of spinal fusion. METHODS: All animals underwent Faxitron radiographs at 2, 4, and 6 weeks, manual spine palpation at 6 weeks, and high-resolution micro computerized tomography (microCT) at 6 weeks. Spinal fusion rate was assessed by: 1) 6-week Faxitron images; 2) manual palpation by three independent observers; 3) microCT; and 4) histology. New bone formation was assessed by hematoxylin-eosin and Masson trichrome staining on decalcified, coronally sectioned spine segments. RESULTS: All differences achieved statistical significance. After 6 weeks, direct application of adenoviral Nell-1 in a DBM carrier achieved significantly higher rates of spinal fusion over Lac Z controls: 60% Nell-1 versus 20% Lac Z by manual palpation and 70% Nell-1 versus 20% Lac Z by microCT and histology. Histological assessment of bone quality and maturity revealed more mature, higher quality bone in all the Nell-1 treated specimens relative to Lac Z at 6 weeks. CONCLUSIONS: Spinal fusion is more accurately assessed by microCT and histology than manual palpation. Direct application of adenoviral Nell-1 in a DBM carrier achieved significantly higher rates of spinal fusion over Lac Z controls at 6 weeks. Direct application of adenoviral Nell-1 in a DBM carrier also achieved significantly higher rates of spinal fusion over other reports in the literature using direct adenoviral BMP application. Direct application of adenoviral BMP in an allograft carrier achieved 8% fusion for BMP-2 and 16% fusion for BMP-7 at 8 weeks. These results indicate that Nell-1 may be a potent osteoinductive molecule. In addition, the regulation of Nell-1 by the master bone regulatory gene, Runx2 suggests that Nell-1 may exert its effects more specifically in osteoblastic cells than BMPs which affect multiple cell types. Overall, Nell-1 may fulfil a current need for an osteoinductive factor.

Adenoviridae↗
PubMed2006

Cervical epidural steroid injections for symptomatic disc herniations.

OBJECTIVES: Cervical disc herniations are a common cause of radicular pain from nerve root impingement and may necessitate surgical decompression to alleviate symptoms. The use of cervical epidural injections has not been studied in detail. The objective of this retrospective study was to examine the efficacy of cervical epidural steroid injections for the treatment of symptomatic herniated cervical discs. METHODS: Patients with herniated cervical discs without myelopathy that had failed conservative management and were otherwise surgical candidates were offered a trial of cervical epidural injections. The results and benefits of the injections were examined as well as the incidence of proceeding to surgical intervention. RESULTS: Of the 70 treated patients, 44 (63%) had significant relief of their symptoms and did not wish to proceed with surgical treatment. Of the 26 patients who underwent surgical decompression, 92% had successful resolution of their symptoms. The nonsurgical and surgical groups were similar in terms of gender, preinjection symptoms, or number of injections. However, significant differences between the two groups were found with regard to age (P<0.05) and time from initial consultation to initial injection (P<0.05). With an average of 13-month follow-up, 45 (65.3%) patients reported a good/excellent result per Odom criteria. In addition, 53 (75%) would attempt cervical epidural steroid injections again in the future. No complications were noted in our series. CONCLUSIONS: Cervical epidural injections are a reasonable part of the nonoperative treatment of patients with symptomatic cervical disc herniations. The success rates appear to be very similar to prior studies of lumbar epidural injections for symptomatic lumbar disc herniations. It appears that a large percentage of the patients may obtain relief from radicular symptoms and avoid surgery for the follow-up period up to 1 year. In addition, patients older than 50 years and those who received the injections earlier, less than 100 days from diagnosis, seemed to have a more favorable outcome.

Adult↗
PubMed2006

Total disk arthroplasty.

Spinal fusion remains the gold standard for surgical management of instability and mechanical low back or neck pain. However, even in carefully selected patients, successful clinical results can be difficult to achieve. Reasons for failure include pseudarthrosis and adjacent spine segment disease. The theoretic advantages of removing the painful disk while preserving motion have led to increasing interest in total disk arthroplasty. Although disk replacements have been implanted in Europe for decades, the procedure is relatively new in the United States. Recently, two artificial disks for symptomatic lumbar degenerative disk disease have been approved by the US Food and Drug Administration; several others are undergoing clinical trials. Short-term studies demonstrate similar clinical improvements for both disk replacements and fusion procedures at up to 2-year follow-up. Issues requiring further research include optimal design specifications, potential complications, and appropriate patient selection. Consequently, the long-term benefit of total disk arthroplasty over fusion for the treatment of axial low back or neck pain remains to be determined.

Arthroplasty, Replacement↗
PubMed2005

An outcomes analysis of the treatment of cervical pseudarthrosis with posterior fusion.

STUDY DESIGN: A retrospective review of 33 consecutive patients treated with posterior fusion and selective nerve root decompression for the treatment of pseudarthrosis following anterior cervical discectomy and fusion. OBJECTIVES: Use standardized outcome measures to evaluate the results of posterior fusion with selective nerve root decompression as a treatment option for symptomatic pseudarthrosis of the cervical spine. SUMMARY OF BACKGROUND DATA: Pseudarthrosis after anterior cervical discectomy and fusion has been recognized as a cause of continued cervical pain and unsatisfactory outcomes. Debate continues as to whether a revision anterior approach or a posterior fusion procedure is the best treatment for symptomatic cervical pseudarthrosis. To our knowledge, standardized outcome measures have not been used to evaluate the results of either surgical treatment option; therefore, it is difficult to evaluate outcomes in these patients, let alone compare surgical treatment options. Data on fusion rates in these two surgical treatment groups suggest a trend of a higher fusion rate with utilization of a posterior revision procedure, but the largest study to date includes the study of only 19 patients treated with a posterior fusion. METHODS: Thirty-three consecutive patients with symptomatic pseudarthrosis following anterior cervical discectomy and fusion were treated with selective nerve root decompression and posterior fusion using iliac crest or local bone graft as well as posterior wiring and/or lateral mass plating. The average follow-up period was 46 months (range, 20-86 months). Patients were assessed using physical examination, flexion-extension lateral radiographs, and standardized outcome measures including the SF-36, Arthritis Impact Measurement Scales 2, and Cervical Spine Outcomes Questionnaire. RESULTS: All 33 patients (100%) demonstrated a solid fusion at their most recent follow-up, and all 33 patients noted significant improvement in their preoperative symptoms. No difference in fusion status was noted between those treated with iliac crest versus patients treated with local bone graft--all had a solid fusion; 72% of the patients were satisfied with the result of their surgery. Cervical Spine Outcomes Questionnaire pain scales demonstrated 52% of patients reported mild or nopain at follow-up, whereas 20% described their pain as "discomforting" and 28% of the patients continued to report moderate to severe pain. CONCLUSIONS: This is the first study to our knowledge to use standardized outcome measures to assess clinical outcome in patients treated with posterior fusion for pseudarthrosis after anterior cervical discectomy and fusion. Patients and surgeons need to understand the potential for success with this revision procedure but also be aware of the relatively high rate of continued moderate to severe pain observed in this patient population even after a solid fusion is achieved. All of the patients in this study fused with a single posterior fusion procedure, further supporting the relatively higher fusion rates observed in the literature using posterior fusion as a treatment for cervical pseudarthrosis. Our results also support the ability of surgeons to use local bone graft without iliac crest in a posterior fusion for cervical pseudarthrosis and therefore avoid the morbidity associated with iliac crest bone graft harvest.

Adult↗
PubMed2005

Genetically modified human derived bone marrow cells for posterolateral lumbar spine fusion in athymic rats: beyond conventional autologous bone grafting.

STUDY DESIGN: This experimental study consisted of four groups. In Group I, 8 animals were implanted with a collagen sponge containing 5 million human-derived bone marrow cells (HBMCs) infected with the BMP-2-containing adenovirus. In Group II, 5 animals were implanted with a collagen sponge containing 5 million HBMCs, which had been infected with an adenovirus containing the cDNA for the lacZ gene. In Group III, 5 animals were implanted with a collagen sponge containing 5 million uninfected HBMCs. In Group IV, 5 animals were implanted with a collagen sponge alone. All animals were killed at 12 weeks. OBJECTIVES: The purpose of this study was to assess the ability of HBMCs infected with a BMP-2 adenovirus to induce a posterolateral spine in an athymic rat model. SUMMARY OF BACKGROUND DATA: High pseudarthrosis rates after attempted spinal arthrodesis as well as the morbidity associated with iliac crest bone graft harvest make alternative bone graft materials desirable. Alternatives include allograft bone, demineralized bone matrices, and more recently, recombinant bone morphogenetic proteins. However, high doses of the recombinant protein are required, and a single dose of recombinant protein may not induce a sufficient osteoinductive response in all patients. An alternative strategy is to genetically manipulate cells to overexpress a bone morphogenetic protein. METHODS: HBMCs grown in culture were infected with an adenovirus containing the cDNA for BMP-2 (AdBMP-2) or the gene for beta-galactosidase (AdlacZ). Cells were implanted on the decorticated transverse processes of L4-L5 as previously described. Rats were assessed by radiographs at 4-week intervals and were killed at 12 weeks. After death, spines were explanted and assessed by manual palpation and histologic analysis. RESULTS: Eight of eight rats implanted with AdBMP-2-infected HBMCs (Group I) were fused by radiographic evaluation and manual palpation at 12 weeks. Control groups consisted of: 5 rats implanted with the collagen sponge alone (Group II), 5 rats implanted with a collagen sponge and 5 million uninfected HBMCs (Group III), and 5 rats implanted with HBMCs infected with AdlacZ (Group IV). None of the rats in the control groups (0 of 15) developed a fusion at L4-L5. CONCLUSION: This study demonstrates that human-derived bone marrow cells can be infected with a BMP-2-containing adenovirus and produce sufficient bone in vivo to fuse the lumbar spine.

Adenoviridae↗
PubMed2005

The efficacy of different commercially available demineralized bone matrix substances in an athymic rat model.

OBJECTIVE: Bone graft substitutes have been developed because there is a limited supply of autogenous graft and the harvesting of iliac crest bone graft is associated with significant morbidity. Currently, there are a number of different commercially available demineralized bone matrix (DBM) products available that have been prepared by different methods and have different carriers. The objective of this study was to compare eight different commercially available DBM products. METHODS: Eight different DBMs were used to attempt a spinal fusion between the L4-L5 transverse processes in athymic rats. There were 10 rats in each group, and 5 rats were killed at both 4 and 8 weeks. Radiographic and histologic analyses were performed. Manual palpation testing was also performed. RESULTS: At 4 weeks, Osteofil Paste had the highest radiographic scores, whereas Grafton Putty had the best radiographic scores at 8 weeks. Conversely, the spines implanted with Allomatrix had the lowest radiographic scores at both 4 and 8 weeks. In regard to forming a spinal fusion confirmed by manual palpation, Osteofil Paste was the most effective at 4 weeks, whereas Grafton Flex and Grafton Putty had the highest rate of fusion at 8 weeks. Conversely, the lowest rates of fusion were seen in the Allomatrix and Grafton Crunch groups. Statistical analysis showed that there were significant differences among the groups seen on radiographs and by manual palpation. Qualitative differences could be appreciated between the groups histologically. CONCLUSION: Significant differences exist among commercially available DBMs in forming a spinal fusion in an athymic rat.

Animals↗
PubMed2005

The mechanical and thermal effects of focused ultrasound in a model biological material.

This paper is motivated by possible medical applications of focused ultrasound in the minimally invasive treatment of a variety of musculoskeletal disorders that are responsive to thermal treatment. A model-based analysis of the interaction of high-intensity focused ultrasound with biological materials is carried out in an effort to predict the path of the sound waves and the temperature field in the focal region. A finite-element-based general purpose code called PZFlex is used to determine the effects of nonlinearity and geometrical complexity of biological structures. It was found that at frequencies of interest in therapeutic applications, the nonlinear effects are usually negligible and the geometrical complexities can be handled through a substructuring procedure. An approximate analytical method with acceptable accuracy is developed as an alternative to the purely numerical approach used in PZFlex. The mechanical and thermal effects in two-layered fluid material systems induced by high-frequency focused ultrasound are calculated through this analytical method. The results are compared with those obtained using PZFlex as a benchmark.

Biomechanical Phenomena↗
PubMed2004

Reduction of leg pain and lower-extremity weakness for 1 year with Oxiplex/SP gel following laminectomy, laminotomy, and discectomy.

OBJECT: Although good surgical technique is effective in reducing postoperative epidural fibrosis, compression or tethering of the nerve root may cause recurrent radicular pain and physical impairment. The implantation of a bioresorbable gel on the dura may further decrease the amount of scar formation after surgery and thus improve the patient's ability to perform activities of daily living (ADL). This study is a 12-month evaluation of the safety and effectiveness of Oxiplex/SP Gel (FzioMed, Inc., San Luis Obispo, CA) in the reduction of pain and radiculopathy after lumbar discectomy. METHODS: A pilot randomized single-blind multicenter clinical trial was conducted to evaluate the performance of Oxiplex/SP Gel in patients who underwent surgery for unilateral herniation of the lumbar disc at L4-5 or L5-S1. Eighteen patients with severe leg pain and lower-extremity weakness (11 women and seven men) were randomly assigned intraoperatively to receive the gel at the conclusion of surgery (treatment group) or to undergo surgery alone (control group). Self-assessment questionnaires (Lumbar Spine Outcomes Questionnaire) to assess pain, symptoms, and ADL were completed preoperatively and at scheduled postoperative intervals (30 days, 90 days, 6 months, and 12 months). The authors examined the spine and lower extremities of patients scheduled for discectomy to assess neurological function and pain. Treated patients received sufficient Oxiplex/SP Gel (1-3 ml) to coat the nerve root and fill the epidural space. Postoperative clinical evaluations were performed at 30 and 90 days. Patients completed the self-assessment questionnaires at baseline and were contacted by telephone or mail for the completion of the postoperative self-assessment questionnaires. Surgical procedures were well tolerated; no device-related adverse events and no clinically significant laboratory results were reported. The 11 patients with severe leg pain and lower-extremity weakness who were treated with Oxiplex/SP Gel had a reduction in those symptoms at 30 days, 90 days, 6 months, and 12 months after discectomy, compared with the seven control patients who underwent surgery only. CONCLUSIONS: Oxiplex/SP Gel was easy to use and safe in patients who underwent unilateral discectomy. A greater benefit in clinical outcome measures was seen over the 12-month follow-up period in gel-treated patients.

Activities of Daily Living↗
PubMed2004

Adjacent two-level lumbar discectomy: outcome and SF-36 functional assessment.

STUDY DESIGN: A retrospective outcomes study. OBJECTIVES: To examine the outcome following adjacent two-level lumbar discectomy using both surgeon-based evaluation criteria and validated patient-based quality of life instrument (SF-36). SUMMARY OF BACKGROUND DATA: Lumbar discectomies have documented success rates between 49% and 98% for single-level procedures. However, no prior study has specifically examined the outcome following adjacent two-level lumbar discectomy in a large series of patients. METHODS: This study analyzed 55 patients with a minimum 2-year follow-up. All patients underwent adjacent two-level lumbar discectomy for radicular pain attributable to nerve root impingement at the corresponding levels. The patients were divided into two diagnostic groups based on their preoperative radiographic studies. Patients with two-level adjacent posterolateral lumbar disc herniations without concomitant osseous degenerative changes at the same levels constituted Group 1 (22 patients). Patients with associated osseous degenerative changes at the same levels made up Group 2 (33 patients). The patients' clinical outcome was assessed using the MacNab classification and SF-36 questionnaire. RESULTS: The average duration of follow-up was 41 months (range 24-96 months). The group consisted of 35 males and 20 females with average age of 49 years (range 19-82 years). Excellent results were observed in 49%, good in 20%, fair in 15%, and poor in 16%. However, patients in Group 1 have 86% excellent/good results, whereas patients in Group 2 have 57% excellent/good results. Overall, 15% of the patients required reoperation and subsequent spinal fusion. Analysis of the SF-36 scores revealed significant differences based on patient's diagnostic grouping as well. Patients in Group 1 have physical and mental summary scores comparable with age- and sex-adjusted population norms and significantly higher than those in Group 2 (P < 0.01). CONCLUSIONS: Two-level discectomy is an effective treatment with clinical outcome comparable with single-level discectomy. Patients with posterolateral disc herniations and definitive radiculopathy without osseous degenerative changes at the same levels have better clinical outcome and quality of life scores compared with those patients having concomitant degenerative arthritis at the same levels. Patients having two-level discectomy may be at increased risk of requiring subsequent lumbar fusion compared with those with single-level discectomy.

Adult↗
PubMed2004

Adjacent segment degeneration in the lumbar spine.

BACKGROUND: A primary concern after posterior lumbar spine arthrodesis is the potential for adjacent segment degeneration cephalad or caudad to the fusion segment. There is controversy regarding the subsequent degeneration of adjacent segments, and we are aware of no long-term studies that have analyzed both cephalad and caudad degeneration following posterior arthrodesis. A retrospective investigation was performed to determine the rates of degeneration and survival of the motion segments adjacent to the site of a posterior lumbar fusion. METHODS: Two hundred and fifteen patients who had undergone posterior lumbar arthrodesis were included in this study. The study group included 126 female patients and eighty-nine male patients. The average duration of follow-up was 6.7 years. Radiographs were analyzed with regard to arthritic degeneration at the adjacent levels both preoperatively and at the time of the last follow-up visit. Disc spaces were graded on a 4-point arthritic degeneration scale. Correlation analysis was used to determine the contribution of independent variables to the rate of degeneration. Survivorship analysis was performed to describe the degeneration of the adjacent motion segments. RESULTS: Fifty-nine (27.4%) of the 215 patients had evidence of degeneration at the adjacent levels and elected to have an additional decompression (fifteen patients) or arthrodesis (forty-four patients). Kaplan-Meier analysis predicted a disease-free survival rate of 83.5% (95% confidence interval, 77.5% to 89.5%) at five years and of 63.9% (95% confidence interval, 54.0% to 73.8%) at ten years after the index operation. Although there was a trend toward progression of the arthritic grade at the adjacent disc levels, there was no significant correlation, with the numbers available, between the preoperative arthritic grade and the need for additional surgery. CONCLUSIONS: The rate of symptomatic degeneration at an adjacent segment warranting either decompression or arthrodesis was predicted to be 16.5% at five years and 36.1% at ten years. There appeared to be no correlation with the length of fusion or the preoperative arthritic degeneration of the adjacent segment.

Adolescent↗
PubMed2003

L5-S1 segment survivorship and clinical outcome analysis after L4-L5 isolated fusion.

STUDY DESIGN: A retrospective investigation of the L5-S1 motion segment after an isolated L4-L5 posterior lumbar fusion. OBJECTIVE: To determine the survivorship of the L5-S1 segment in patients undergoing L4-L5 fusion and to identify the correlation between radiographic degeneration and clinical outcome at this level. SUMMARY OF BACKGROUND DATA: There is current controversy regarding future degeneration of the L5-S1 segment following single-segment fusion at L4-L5. There are no long-term studies that look at L5-S1 after L4-L5 fusion to assess the rate of degeneration at this adjacent segment and the functional clinical outcome of the patient. METHODS: Thirty-two consecutive patients (average age 56.4 years, range 27-77 years) having isolated L4-L5 posterior spinal fusion for instability or stenosis by a single surgeon were included in this study. There were 25 females and 7 males with an average follow-up of 7.3 years (range 2.3-12.4 years). A survivorship analysis was performed to determine the degeneration at the adjacent L5-S1 segment. Radiographs were analyzed for arthritic degeneration at that level. At the time of the L4-L5 index procedure, the L5-S1 disc spaces were graded on a 4-point scale for degeneration. Questionnaires were submitted by mail, and telephone interviews were conducted by one of the authors to determine the current level of patient function. RESULTS: Of the total 32 patients assessed, 31 (97%) had no evidence of symptomatic degeneration at L5-S1 requiring additional decompression or fusion. One patient had clinical symptoms that required a foraminotomy and laminotomy at L5-S1, but none of the patients required any further fusion. Although there was a trend of progression of the arthritic grade at L5-S1 from preoperative to postoperative examination, there was no correlation between preoperative arthritic grade versus further degeneration. The discs showed progression of degeneration from an average score of 2.28 before surgery to a score of 2.49 after surgery at the last follow-up. CONCLUSION: There appears to be no need to routinely include the L5-S1 segment when performing a posterior lumbar fusion for patients with instability or stenosis at L4-L5 if no symptoms are attributed to the lumbosacral level. At an average of 7.3 years, there was neither increased symptomatic disc degeneration nor symptoms necessitating the need for an L5-S1 fusion.

Adult↗
PubMed2003

Graft migration or displacement after multilevel cervical corpectomy and strut grafting.

STUDY DESIGN: A retrospective review of consecutive patients with graft migration or displacement after anterior cervical corpectomy surgery was performed. OBJECTIVES: To examine the associated risk factors and results of treatment among patients who sustained graft displacement or migration after anterior cervical corpectomy surgery. SUMMARY OF BACKGROUND DATA: Graft migration or displacement after anterior cervical corpectomy is a potential complication that may require revision surgery, but because of the low incidence, the factors associated with graft movement and the results of treatment are not well defined. METHODS: All patients who had undergone a cervical corpectomy were examined for graft migration or displacement. None of the patients had a previous cervical laminectomy or prior posterior cervical surgery. All the patients were treated with autogenous strut grafting after decompression. RESULTS: Over a 25-year period, 249 consecutive patients underwent one- to five-level anterior cervical corpectomies and strut grafting. All the patients were fused using autogenous bone grafts (iliac crest or fibula). During the postoperative period, 16 of the patients (10 women and 6 men; average age, 61.4 years) experienced migration of their grafts. The average follow-up period was 4.7 years (range, 2-12 years). The graft migration rates increased with more levels of fusion (odds ratio of 1.65 for having a displaced graft with each additional level): 4 of 95 single-level grafts, 4 of 76 two-level grafts, 7 of 71 three-level grafts, and 1 of 6 for four-level grafts. Of the 16 patients with graft migration, 14 had procedures involving a corpectomy of C6 with a fusion inferiorly extending to the C7 vertebral body (P = 0.001, statistically significant difference). Of these 16 patients, 5 underwent revision surgeries acutely for displacement and associated fracture of the inferior graft and vertebral body junction. None of the patients sustained a neurologic or respiratory complication as a result of graft migration ordisplacement. All of the patients went on to successfulfusion. CONCLUSIONS: This study demonstrated that a greater number of vertebral bodies removed and a longer graft are directly related to an increased frequency of graft displacement. Graft displacement may require revision surgery, but no patient in this study experienced a permanent adverse result from this complication. Corpectomies involving a fusion ending at the C7 vertebral body were associated with a higher rate of graft migration.

Adult↗
PubMed2003

Reduction of radiculopathy and pain with Oxiplex/SP gel after laminectomy, laminotomy, and discectomy: a pilot clinical study.

STUDY DESIGN: Safety using Oxiplex/SP Gel during single-level discectomy for reduction of symptoms associated with unilateral herniation of the lumbar disc was investigated by self-assessment questionnaire and magnetic resonance imaging. OBJECTIVE: To evaluate the safety and assess the efficacy parameters of Oxiplex/SP Gel. SUMMARY OF BACKGROUND DATA: Animal studies demonstrated that Oxiplex/SP Gel (CMC/PEO) reduced epidural fibrosis after lumbar surgery. METHODS: Surgeons examined spine and lower extremities of patients scheduled for discectomy to assess neurologic function and pain. Treated patients received sufficient Oxiplex/SP Gel (1-3 mL) to coat the nerve root and fill the epidural space. The control condition was surgery alone. At baseline, then 30 days, 90 days, and 6 months after surgery, patients completed self-assessment questionnaires concerning leg pain, lower extremity weakness, functional disability, daily living activities, symptoms, and radiculopathy. Magnetic resonance imaging was performed at baseline and 90 days after surgery. At 30 and 90 days after surgery, patients underwent physical examination, wound inspection, and laboratory tests. RESULTS: The surgical procedures were well tolerated by the 23 patients treated with Oxiplex/SP Gel and the 11 control patients. There were no unanticipated adverse events, no clinically significant laboratory results, and no significant differences detected by magnetic resonance imaging. Treated patients had greater reduction in outcome measures at 30 days. The differences in scores were attenuated at 90 days and 6 months. A subgroup, the patients with significant leg pain and weakness at baseline (11 patients treated with Oxiplex/SP Gel and 7 control patients), had greater reduction in outcome measures than the control patients throughout the study. CONCLUSIONS: Oxiplex/SP Gel was easy to use and safe for patients undergoing unilateral discectomy. Greater benefit in clinical outcome measures was seen in gel-treated patients, especially those with severe leg pain and weakness at baseline.

Adult↗
PubMed2003

Perioperative complications of threaded cylindrical lumbar interbody fusion devices: anterior versus posterior approach.

Few data are available to evaluate approach-related differences in perioperative complications with lumbar interbody fusion devices. Complications occurring in the intraoperative and immediate postoperative period were identified and categorized for 31 consecutive posterior lumbar interbody fusions (PLIFs) and 88 consecutive anterior lumbar interbody fusions (ALIFs). In this study, all lumbar interbody fusions were conducted with threaded cylindrical devices as stand-alone internal fixation devices. Multivariate analysis was used to account for potential covariates and identify factors associated with an increased complication risk. Twenty-two percent of the patients had a perioperative complication. The relative risk of having a perioperative complication was 4.75 times higher for the PLIF group. All intraoperative complications occurred in the PLIF group. The relative risk of having a major postoperative complication was 6.8 times higher in the PLIF group than the ALIF group. Anterior approached patients tended to have visceral (ileus, 6%) and vascular (deep venous thrombosis, 2%) complications. In the posterior group, complications were neurologic and dura related (pseudomeningocele, 16%; epidural hematoma, 3%) and occurred most frequently in patients that had had previous posterior lumbar surgery (31% with major complication).

Adult↗