Rick C. Sasso

Comparison of BRYAN Cervical Disc Arthroplasty With Anterior Cervical Decompression and Fusion : Clinical and Radiographic Results of a Randomized, Controlled, Clinical Trial

Study Design. A prospective, randomized, multicenter study of surgical treatment of cervical disc disease. Objective. To assess the safety and efficacy of cervical disc arthroplasty using a new arthroplasty device at 24-months follow-up. Summary of Background Data. Cervical disc arthroplasty preserves motion in the cervical spine. It is an alternative to fusion after neurologic decompression, whereas anterior decompression and fusion provides a rigorous comparative benchmark of success. Methods. We conducted a randomized controlled multicenter clinical trial enrolling patients with cervical disc disease. Ultimately 242 received the investigational device (Bryan Cervical Disc), and 221 patients underwent a single-level anterior cervical discectomy and decompression and fusion as a control group. Patients completed clinical and radiographic follow-up examinations at regular intervals for 2 years after surgery. Results. Analysis of 12- and 24-month postoperative data showed improvement in all clinical outcome measures for both groups; however, 24 months after surgery, the investigational group patients treated with the artificial disc had a statistically greater improvement in the primary outcome variables: Neck disability index score (P = 0.025) and overall success (P = 0.010). With regard to implant- or implant/surgical-procedure-associated serious adverse events, the investigational group had a rate of 1.7% and the control group, 3.2%. There was no statistical difference between the 2 groups with regard to the rate of secondary surgical procedures performed subsequentto the index procedure. Patients who received the artificial cervical disc returned to work nearly 2 weeks earlier than the fusion patients (P = 0.015). Conclusion. Two-year follow-up results indicate that cervical disc arthroplasty is a viable alternative to anterior cervical discectomy and fusion in patients with persistently symptomatic, single-level cervical disc disease.

Iliac crest bone graft donor site pain after anterior lumbar interbody fusion: a prospective patient satisfaction outcome assessment.

Background: Autogenous iliac crest bone is the gold-standard graft for spinal fusion surgery. Unfortunately, there is a frequent incidence of graft site pain that persists well into the postoperative period with complication rates reported in 2.8-39% of patients. Persistent pain lasting at least 2 years is reported in 15-39% of patients. Objective: The objective of this work was to determine the incidence of acute and persistent pain as well as patient assessment of graft site appearance following iliac crest bone graft harvest for anterior lumbar interbody fusion (ALIF). The control arms of four randomized prospective multicenter clinical trials evaluating recombinant human bone morphogenetic protein-2 (rhBMP-2) versus autogenous iliac crest bone graft were combined. Two hundred eight patients underwent iliac crest bone graft harvest for ALIF in threaded cylindrical cages or threaded bone dowels. Patients were assessed at each postoperative visit with questionnaires evaluating graft site pain intensity, duration, and appearance. Methods: Two hundred eight patients underwent iliac crest bone graft harvest for ALIF as the control group of four randomized prospective multicenter clinical trials evaluating rhBMP-2 versus autogenous iliac crest bone graft in threaded cylindrical cages or threaded bone dowels. Most patients in the control group had anterior iliac crest graft harvest, equally from the right and left side. Three grafts (1.4%) were taken from the posterior crest and six (2.9%) were tricortical. Follow-up was obtained at hospital discharge, 6 weeks, 3, 6, 12, and 24 months. A pain evaluation score was made up of two Visual Analog Scales: one scale measuring intensity, the other frequency of pain. For the intensity scale, a rating of “0” meant no pain and “10” was “as bad as it could be.” For the frequency scale, a rating of “0” meant pain was present “none of the time” and “10” meant it was present “all the time.” Combining these scales, a total score of 20 indicated the worst pain was present all the time. Patients were also questioned about the graft site appearance. Results: Two hundred eight patients underwent iliac crest harvest, and prospective data were available on 202 patients. At hospital discharge, 2 patients (1%) had no pain; this increased to 34 of 199 (17%) at 6 weeks postoperatively and to 85 of 199 patients (43%) at 3 months. However, 41% of patients reported pain at 6 months postoperatively (79/192), and 33% of 168 reported pain at 1 year. One hundred forty-one of 208 patients completed a survey at 24 months, with 31% reporting some level of pain. At hospital discharge, the graft site pain score ranged from 0 to 20 with a mean of 12.8, decreasing to 7.3 at 6 weeks, to 3.8 at 3 months, and to 2.9, 2.4, and 1.8 at 6, 12, and 24 months, respectively. At all time intervals, P values from t tests comparing the mean with 0 were <0.001. Graft site appearance at discharge was good in 49% of patients, fair in 40%, and poor in 11%. At 6 weeks, appearance was good in 69%, fair in 27%, and poor in 5%; at 3 months, it was good in 75%, fair in 24%, and poor in 2%; at 6 months, it was good in 82%, fair in 15%, and poor in 3%; at 12 months, it was good in 82% and fair or poor in 19%; and at 24 months, it was good in 84% and fair or poor in 16%. There was no significant difference between posterior and anterior harvest sites or bicortical grafts, and all were included in the analysis. Right or left side demonstrated no differences. Discussion: This is the first study known to the authors presenting results of prospective data collected in a multicenter study evaluating iliac crest harvest site pain, both intensity and frequency, as well as graft site appearance. The results demonstrate that 31% of patients had persistent pain at 24 months postoperatively and 16% reported fair or poor appearance of their graft site. Conclusions: Persistent donor site pain remains a problem with harvest of autogenous iliac crest bone graft for spinal fusion. This prospective study, the first such study reported for ALIF, confirms that donor site pain remains a significant postoperative management problem.

Clinical outcomes of BRYAN cervical disc arthroplasty: a prospective, randomized, controlled, multicenter trial with 24-month follow-up.

Study Design/Setting Prospective, randomized, 3-center, clinical trial. Objective To prospectively compare the outcomes of cervical arthroplasty with the BRYAN Cervical Disc Prosthesis (Medtronic Sofamor Danek, Inc, Memphis, TN) to anterior cervical discectomy and fusion (ACDF). Summary of Background Data Surgical treatment of cervical disc pathology commonly involves techniques that employ discectomy and fusion (ACDF). This “gold-standard” technique has demonstrated good clinical and radiographic outcomes. Common adverse effects of this procedure are associated with the adjacent level degeneration and bone-graft harvest. Several investigators have independently reported successful short-term outcomes with the BRYAN Cervical Disc Prosthesis. In addition, a significant body of knowledge has been collected regarding the wear patterns and adjacent level effects of this device in human and animal models. Methods As part of an FDA IDE trial, 3 centers collected prospective outcomes data on 115 patients randomized in a 1:1 ratio to ACDF (Control group) or arthroplasty with the BRYAN Cervical Disc Prosthesis (Investigational group). Results Demographic and surgical data were generally similar in the 2 populations. Outcomes data collected at routine postoperative intervals for 24 months demonstrated that the Investigational group had statistically significant (P<0.05) improvements as assessed by the Neck Disability Index, the Neck Pain Score, and SF-36 Physical component scores. The improvement in the Mental Component Subscore values for the BRYAN and control groups was equivalent at 24 months (P=0.055). Arm pain relief was similar in both groups (P=0.152). During the course of the 2-year follow-up, 4 patients in the Control group required surgical intervention and 3 patients in the Investigational group required ACDF for adjacent level disease. Conclusions At 24 months, cervical arthroplasty with the BRYAN Cervical Disc Prosthesis compares favorably with ACDF as defined by standard outcomes scores.

Retrograde Ejaculation After Anterior Lumbar Interbody Fusion : Transperitoneal Versus Retroperitoneal Exposure

Study Design. In this multicenter, prospective, 2-year study, 146 male patients underwent a single-level anterior lumbar interbody fusion with a tapered threaded titanium fusion device. All the patients were advised before surgery of the risk for retrograde ejaculation. After surgery, any case of retrograde ejaculation was recorded as an adverse event, and the patient was observed up for the remainder of the study. Objective. To determine the incidence of retrograde ejaculation in male patients treated for single-level degenerative lumbar disc disease at L4–L5 or L5–S1 with a stand-alone anterior interbody fusion using tapered, threaded titanium fusion cages. Summary of Background Data. The incidence of retrograde ejaculation in men after anterior lumbosacral spinal surgery has been reported to range from 0.42% to 5.9%. Various risk factors that increase the chance of retrograde ejaculation have been proposed. Methods. In this prospective study, 146 male patients underwent an open surgical exposure of the lumbosacral junction and a single-level interbody fusion at either L4–L5 or L5–S1. Assessment of a patient’s clinical outcome was based on written questionnaires at 6 weeks and then 3, 6, 12, and 24 months after surgery. Patients were questioned about adverse events at each of these assessments, and any case of retrograde ejaculation was recorded and followed. Results. Retrograde ejaculation developed in 6 of the 146 men after open anterior lumbar interbody fusion surgery. Two cases (1.7%; 2/116) involved patients who underwent a retroperitoneal surgical exposure. Four cases (13.3%; 4/30) involved patients who had a transperitoneal surgical exposure. This difference is statistically significant according to Fisher’s exact test (P = 0.017). At 12 months after surgery, 2 patients had resolution of their symptoms: 1 in the retroperitoneal approach group and 1 in the transperitoneal group. At the final 2-year follow-up, no changes in symptoms were reported. One patient in the retroperitoneal approach group (0.86%) and three patients in the transperitoneal group (10%) reported permanent retrograde ejaculation (P = 0.027). Conclusions. A transperitoneal approach to the lumbar spine at L4–L5 and L5-S1 has a 10 times greater chance of causing retrograde ejaculation in men than a retroperitoneal approach.

Artificial disc versus fusion: a prospective, randomized study with 2-year follow-up on 99 patients.

Study Design. A total of 115 patients were randomized in a 1:1 ratio to a Bryan artificial disc replacement (56) or an anterior cervical fusion with allograft and a plate (59). Objective. The purpose of this study is to examine the functional outcome and radiographic results of this prospective, randomized trial to determine the role of the Bryan artificial cervical disc replacement for patients with 1-level cervical disc disease. Summary of Background Data. Artificial cervical disc replacement has become an option for cervical radiculopathy. Previous studies have evaluated the efficacy of this alternative without the scientific rigor of a concurrent control population. This study is a pooled data set from 3 centers involved in the U.S. FDA Investigational Device Exemption trial evaluating the Bryan artificial cervical disc. Methods. The purpose of this study is to examine the functional outcome and radiographic results of this prospective, randomized trial to determine the role of the Bryan artificial cervical disc replacement for patients with 1-level cervical disc disease; 12-month follow-up is available for 110 patients and 24 month follow-up complete for 99 patients. There are 30 males and 26 females in the Bryan group and 32 males and 27 females in the fusion group. The average age was 43 years (Bryan) and 46 years (fusion). Disability and pain were assessed using the Neck Disability Index (NDI) and the Visual Analog Scale (VAS) of the neck and of the arm pain. SF-36 outcome measures were obtained including the physical component as well as the mental component scores. Range of motion was determined by independent radiologic assessment of flexion-extension radiographs. We report a prospective, randomized study comparing the functional outcome of cervical disc replacement to an anterior cervical fusion with results of 99 patients at 2 years. Prospective data were collected before surgery and at 6 weeks, 3, 6, 12, and 24 months after surgery. Results. The average operative time for the control group was 1.1 hours and the Bryan Group 1.7 hours.Average blood loss was 49 mL (control) and 64 mL (Bryan). Average hospital stay was 0.6 days (control) and 0.9 days (Bryan). The mean NDI before surgery was not statistically different between groups: 47 (Bryan) and 49 (control). Twelve-month follow-up NDI is 10 (Bryan) and 18 (control) (P = 0.013). At 2-year follow-up, NDI for the Bryan group is 11 and the control group is 20 (P = 0.005). The mean arm pain VAS before surgery was 70 (Bryan) and 71 (control). At 1-year follow-up, Bryan arm pain VAS was 12 and control 23 (P = 0.031). At 2-year follow-up, the average arm pain VAS for the Bryan group was 14 and control 28 (P = 0.014). The mean neck pain VAS before surgery was 72 (Bryan) and 73 (control). One-year follow-up scores were 17 (Bryan) and 28 (control) (P = 0.05). At 2 years: 16 (Bryan) and 32 (control) (P = 0.005). SF-36 scores: Physical component- Before surgery Bryan 34 and control 32. At 24 months: Bryan 51 and control 46 (P = 0.009). More motion was retained after surgery in the disc replacement group than the plated group at the index level (P < 0.006 at 3, 6, 12, and 24 months). The disc replacement group retained an average of 7.9° of flexion-extension at 24 months. In contrast, the average range of motion in the fusion group was 0.6° at 24 months. There were 6 additional operations in this series: 4 in the control group and 2 in the investigational group. There were no intraoperative complications, no vascular or neurologic complications, no spontaneous fusions, and no device failures or explantations in the Bryan cohort. Conclusion. The Bryan artificial disc replacement compares favorably to anterior cervical discectomy and fusion for the treatment of patients with 1-level cervical disc disease. At the 2-year follow-up, there are statistically significant differences between the groups with improvements in the NDI, the neck pain and arm pain VAS scores, and the SF-36 physical component score in the Bryan disc population.

Results of Cervical Arthroplasty Compared with Anterior Discectomy and Fusion: Four-Year Clinical Outcomes in a Prospective, Randomized Controlled Trial

BACKGROUND The published two-year results of the pivotal U.S. Food and Drug Administration investigational device exemption trial with the use of the Bryan cervical disc arthroplasty compared with anterior cervical discectomy with fusion for treating single-level degenerative cervical disc disease revealed a significantly superior overall success rate in the arthroplasty group. The purpose of this study was to evaluate the midterm safety and effectiveness of the Bryan disc as an alternative to arthrodesis following anterior cervical discectomy. METHODS A prospective, multicenter randomized clinical trial was undertaken for the treatment of persistent radiculopathy or myelopathy due to single-level cervical disc herniations or spondylosis. Patients were randomized to treatment with either the Bryan disc (the arthroplasty group; 242 patients) or anterior cervical discectomy and fusion (the fusion group; 221 patients). Patients completed preoperative and postoperative self-assessment forms at specified intervals and had radiographs made preoperatively, at six weeks, and at three, six, twelve, twenty-four, and forty-eight months after surgery. The primary outcome measure was overall success, a composite variable of safety and efficacy measures. Numerous secondary measures were assessed. The follow-up data for up to twenty-four months have been previously published. We report in the present study the forty-eight-month data collected on 181 patients who received the Bryan disc and 138 patients who underwent anterior cervical discectomy and fusion. RESULTS The study groups were demographically similar. Substantial reduction in Neck Disability Index scores occurred in both groups compared with preoperative values. The greater improvement in the Neck Disability Index score in the Bryan disc cohort persisted through the four-year follow-up period (p < 0.001). The four-year overall success rates were 85.1% and 72.5% for the arthroplasty and fusion groups, respectively (p = 0.004). The improvement in the arm pain score was substantial for both groups and significantly greater in the Bryan disc cohort (p = 0.028), and the neck pain scores showed persistently greater improvement in the Bryan disc group at forty-eight months of follow-up (p = 0.001). Short Form-36 physical component score improvement remained greater among the Bryan disc cohort (p = 0.007). The mean range of motion for the Bryan disc was 8.08° and 8.48° at twenty-four and forty-eight months, respectively. Total and serious adverse event rates were similar between the groups. CONCLUSIONS The forty-eight-month follow-up data in the present report showed consistent, sustained significantly superior outcomes for cervical spine arthroplasty compared with cervical spine fusion. The arthroplasty cohort continued to show significantly greater improvements in Neck Disability Index, neck pain score, arm pain score, and Short Form-36 physical component score, as well as the primary outcome measure, overall success, at forty-eight months following surgery.

Efficacy and safety of surgical decompression in patients with cervical spondylotic myelopathy: results of the AOSpine North America prospective multi-center study.

BACKGROUND Cervical spondylotic myelopathy is the leading cause of spinal cord dysfunction worldwide. The objective of this study was to evaluate the impact of surgical decompression on functional, quality-of-life, and disability outcomes at one year after surgery in a large cohort of patients with this condition. METHODS Adult patients with symptomatic cervical spondylotic myelopathy and magnetic resonance imaging evidence of spinal cord compression were enrolled at twelve North American centers from 2005 to 2007. At enrollment, the myelopathy was categorized as mild (modified Japanese Orthopaedic Association [mJOA] score ≥ 15), moderate (mJOA = 12 to 14), or severe (mJOA < 12). Patients were followed prospectively for one year, at which point the outcomes of interest included the mJOA score, Nurick grade, Neck Disability Index (NDI), and Short Form-36 version 2 (SF-36v2). All outcomes at one year were compared with the preoperative values with use of univariate paired statistics. Outcomes were also compared among the severity classes with use of one-way analysis of variance. Finally, a multivariate analysis that adjusted for baseline differences among the severity groups was performed. Treatment-related complication data were collected and the overall complication rate was calculated. RESULTS Eighty-five (30.6%) of the 278 enrolled patients had mild cervical spondylotic myelopathy, 110 (39.6%) had moderate disease, and 83 (29.9%) had severe disease preoperatively. One-year follow-up data were available for 222 (85.4%) of 260 patients. There was a significant improvement from baseline to one year postoperatively (p < 0.05) in the mJOA score, Nurick grade, NDI score, and all SF-36v2 health dimensions (including the mental and physical health composite scores) except general health. With the exception of the change in the mJOA, the degree of improvement did not depend on the severity of the preoperative symptoms. These results remained unchanged after adjusting for relevant confounders in the multivariate analysis. Fifty-two patients experienced complications (prevalence, 18.7%), with no significant differences among the severity groups. CONCLUSIONS Surgical decompression for the treatment of cervical spondylotic myelopathy was associated with improvement in functional, disability-related, and quality-of-life outcomes at one year of follow-up for all disease severity categories. Furthermore, complication rates observed in the study were commensurate with those in previously reported cervical spondylotic myelopathy series.

Postoperative infections in spinal implants : classification and analysis : a multicenter study

A multicenter study was undertaken to analyze postoperative wound infections after posterior spinal instrumentation and fusion. The infection rate of these procedures has been documented in multiple reports. From these results, a classification scheme was developed that can guide therapy and determine the populations at risk. The patients were categorized according to two parameters, the first being the severity or type of infection, and the second being the host response or physiologic classification of the patient. This classification scheme is based on the clinical staging system for adult osteomyelitis developed by Cierny. The severity of infection is divided into three groups. Group 1 is a single-organism infection, either superficial or deep. Group 2 is a multiple-organism, deep infection. Group 3 is multiple organisms with myonecrosis. The host response, likewise, is divided into three classes. Class A is a host with normal systemic defenses, metabolic capabilities, and vascularity. Class B patients demonstrate local or multiple systemic diseases, including cigarette smoking. Class C requires an immunocompromised or severely malnourished host. Our data have demonstrated that single organisms, Group 1, generally can be dealt with by single irrigation and debridement, and closure over suction drainage tubes without the use of an inflow-irrigation system. The Group 2 patients, with multiple organisms and deep infection, required an average of three irrigation debridements. They have a higher percentage of successful closures with closed inflow-outflow suction irrigation systems when compared to simple suction drainage systems without constant inflow irrigation. Multiple- organism infections with myonecrosis, Group 3, are ex@ceedingly difficult to manage, and portend a poor outcome. Patients without normal host defenses, Classes B and C, are at high risk for developing postop@erative wound infection. Specifically, this study demon@strated that cigarette smoking may be a significant risk factor.

Perioperative and delayed complications associated with the surgical treatment of cervical spondylotic myelopathy based on 302 patients from the AOSpine North America Cervical Spondylotic Myelopathy Study

OBJECT Rates of complications associated with the surgical treatment of cervical spondylotic myelopathy (CSM) are not clear. Appreciating these risks is important for patient counseling and quality improvement. The authors sought to assess the rates of and risk factors associated with perioperative and delayed complications associated with the surgical treatment of CSM. METHODS Data from the AOSpine North America Cervical Spondylotic Myelopathy Study, a prospective, multicenter study, were analyzed. Outcomes data, including adverse events, were collected in a standardized manner and externally monitored. Rates of perioperative complications (within 30 days of surgery) and delayed complications (31 days to 2 years following surgery) were tabulated and stratified based on clinical factors. RESULTS The study enrolled 302 patients (mean age 57 years, range 29-86) years. Of 332 reported adverse events, 73 were classified as perioperative complications (25 major and 48 minor) in 47 patients (overall perioperative complication rate of 15.6%). The most common perioperative complications included minor cardiopulmonary events (3.0%), dysphagia (3.0%), and superficial wound infection (2.3%). Perioperative worsening of myelopathy was reported in 4 patients (1.3%). Based on 275 patients who completed 2 years of follow-up, there were 14 delayed complications (8 minor, 6 major) in 12 patients, for an overall delayed complication rate of 4.4%. Of patients treated with anterior-only (n = 176), posterior-only (n = 107), and combined anterior-posterior (n = 19) procedures, 11%, 19%, and 37%, respectively, had 1 or more perioperative complications. Compared with anterior-only approaches, posterior-only approaches had a higher rate of wound infection (0.6% vs 4.7%, p = 0.030). Dysphagia was more common with combined anterior-posterior procedures (21.1%) compared with anterior-only procedures (2.3%) or posterior-only procedures (0.9%) (p < 0.001). The incidence of C-5 radiculopathy was not associated with the surgical approach (p = 0.8). The occurrence of perioperative complications was associated with increased age (p = 0.006), combined anterior-posterior procedures (p = 0.016), increased operative time (p = 0.009), and increased operative blood loss (p = 0.005), but it was not associated with comorbidity score, body mass index, modified Japanese Orthopaedic Association score, smoking status, anterior-only versus posterior-only approach, or specific procedures. Multivariate analysis of factors associated with minor or major complications identified age (OR 1.029, 95% CI 1.002-1.057, p = 0.035) and operative time (OR 1.005, 95% CI 1.002-1.008, p = 0.001). Multivariate analysis of factors associated with major complications identified age (OR 1.054, 95% CI 1.015-1.094, p = 0.006) and combined anterior-posterior procedures (OR 5.297, 95% CI 1.626-17.256, p = 0.006). CONCLUSIONS For the surgical treatment of CSM, the vast majority of complications were treatable and without long-term impact. Multivariate factors associated with an increased risk of complications include greater age, increased operative time, and use of combined anterior-posterior procedures.

Occipitocervical fusion with posterior plate and screw instrumentation. A long-term follow-up study.

Study Design. Thirty‐two patients at one institution underwent occipitocervical fusions with posterior plate and screw instrumentation. The average follow‐up was greater than 4 years (50 months). Methods. AO plates and screws were used and in more than 50% of the cases, the Magerl transarticular C1‐C2 screw technique enhanced the occipitocervical instrumentation. In nine patients, cement was used and thus are excluded in evaluation of fusion results. All 23 patients attained solid fusions. No pseudarthrosis occurred. The average time to fusion was 13 weeks. Halos or traction immobilization was not used postoperatively. The average time of the simple orthosis wear was 11 weeks. Patients were out of bed on an average of the second postoperative day with a range of 1‐4 days postoperatively. Reduction of the atlantoaxial joint was required in 10 of the 23 patients. At follow‐up, nine remain reduced. Results. In one patient, the atlantodens interval approximated the preoperative distance and radiographs demonstrated one transarticular C1‐C2 screw was not placed satisfactorily. The average operative time was 172 minutes, and the average blood loss was 956 cc. The neurologic status of the patients improved or remained the same. No patient deteriorated neurologi‐cally. A total of 78 occipital screws were placed. No complications resulted from any of these screws. One intraoperative complication occurred secondary to massive bleeding after a transarticular screw hole was drilled. Bone wax was placed over the drill hole and the bleeding ceased. No postoperative problems occurred in this patient. Most specifically, no central nervous system sequela was evident. Conclusions. The conclusions from this study are that posterior occipitocervical fusion can be performed very safely with plate and screw instrumentation. An extremely high fusion rate can be expected with minimal complications and minimal postoperative immobilization. This technique, however, is technically demanding.