RESUMEN
STUDY DESIGN: The current study of 251 consecutive 1-level anterior cervical reconstructions was undertaken to compare the incidence of dysphagia between cervical disk replacement and conventional anterior cervical fusion and instrumentation. OBJECTIVES: This is a report of 251 patients from 5 investigational centers in the Food and drug Administration's prospective, randomized porous-coated motion (PCM) trial using a validated dysphagia outcomes instrument. The dysphagia data for both PCM and anterior cervical diskectomy and fusion (ACDF) patients were reviewed from 5 centers to (1) compare the severity of dysphagia, (2) compare the postoperative incidence of dysphagia, and (3) to compare the resolution of perioperative dysphagia. SUMMARY OF BACKGROUND DATA: Dysphagia and dysphonia after anterior surgical approaches to the cervical spine have been previously reported. The current prospective, randomized investigation quantifies clinical dysphagia based on 3 criteria-severity, incidence, and resolution-in a time-course evaluation. METHODS: Patients between 18 and 65 years with 1-level symptomatic cervical radiculopathy and/or myelopathy for progressive neurologic symptoms, were randomized to undergo anterior decompression and PCM arthroplasty (N=151) or ACDF (control) (N=100). Patients self-reported dysphagia severity using the Bazaz scale preoperatively and at follow-up. The Bazaz scale has 4 classes of severity based upon the problems with swallowing that the patient has with both liquids and solids. RESULTS: The Bazaz results demonstrate that although both the PCM and ACDF groups exhibited an initial postoperative problem with swallowing, the PCM group continued to improve with increasing time after implantation, whereas the ACDF only improved minimally. The PCM treatments indicated significantly lower incidence of dysphagia at 3 and 12 months postoperatively compared with ACDF controls (P<0.05). An increase in dysphagia severity at either the 6-week or 3-month follow-up visit was reported in 35 (42%) PCM and 29 (64%) ACDF subjects. Long-term resolution of these symptoms was noted in 74% (26/35) of the PCM subjects as compared with 41.4% (12/29) of the ACDF subjects (P=0.015). CONCLUSIONS: In a prospective randomized clinical study the incidence of postoperative dysphagia and the long-term resolution of the dysphagia was greatly improved in the PCM group compared with the instrumented ACDF control group.
Asunto(s)
Artroplastia/efectos adversos , Trastornos de Deglución/epidemiología , Discectomía/efectos adversos , Complicaciones Posoperatorias/epidemiología , Fusión Vertebral/efectos adversos , Espondilosis/cirugía , Adulto , Artroplastia/estadística & datos numéricos , Vértebras Cervicales/patología , Vértebras Cervicales/cirugía , Discectomía/estadística & datos numéricos , Femenino , Humanos , Incidencia , Fijadores Internos/efectos adversos , Disco Intervertebral/patología , Disco Intervertebral/cirugía , Desplazamiento del Disco Intervertebral/patología , Desplazamiento del Disco Intervertebral/fisiopatología , Desplazamiento del Disco Intervertebral/cirugía , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Estudios Prospectivos , Radiculopatía/patología , Radiculopatía/fisiopatología , Radiculopatía/cirugía , Compresión de la Médula Espinal/patología , Compresión de la Médula Espinal/fisiopatología , Compresión de la Médula Espinal/cirugía , Fusión Vertebral/estadística & datos numéricos , Espondilosis/patología , Espondilosis/fisiopatología , Resultado del TratamientoRESUMEN
STUDY DESIGN: Prospective 6-center study. OBJECTIVE.: To evaluate outcomes of cervical disc replacement performed adjacent to a prior cervical fusion. SUMMARY OF BACKGROUND DATA: The use of disc replacement adjacent to a prior anterior cervical decompression and fusion (ACDF) is an attractive reconstructive option, obviating the need for a multilevel fusion. This study reports outcomes from patients with and without previous ACDF receiving the porous coated motion (PCM) artificial cervical disc in a United States Federal Drug Administration Investigational Device Exemption trials. METHODS: Patients between ages of 18 and 65 with single-level cervical radiculopathy and/or myelopathy, unresponsive to at least 6 weeks of nonsurgical therapy, or experiencing progressive neurologic symptoms were enrolled. Clinical outcomes are compared for patients receiving a PCM disc at a level adjacent to a prior ACDF ("adjacent") and those without having previously had fusion ("primary"). RESULTS: 126 PCM patients were primary (mean age: 44.4 years.) and 26 patients had previous "adjacent level" fusion surgery (mean age: 46.4 years). Surgery time was similar in both groups (96 minutes and 98 minutes, respectively; P = 0.761), and mean blood loss was 76 mL and 66 mL in the 2 groups, respectively (P = 0.491). Clinical outcomes using Neck Disability Index and Visual Analog Scores neck and arm scores showed significant improvement after surgery and were similar between groups at all time points. Revision surgery occurred in 2 of 126 primary patients, and in 2 of 26 patients in the adjacent-to-fusion group. CONCLUSION: Although the level adjacent to a prior cervical fusion is subject to increased biomechanical forces, potentially leading to a higher risk of failure, the PCM disc was well tolerated in the short term. The early clinical results of disc replacement adjacent to a prior fusion are good and comparable to the outcomes after primary disc replacement surgery. However, in view of the small study population and short-term follow-up, continued study is mandatory.
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Vértebras Cervicales/cirugía , Discectomía/métodos , Desplazamiento del Disco Intervertebral/cirugía , Prótesis e Implantes , Fusión Vertebral/métodos , Adulto , Vértebras Cervicales/diagnóstico por imagen , Aleaciones de Cromo , Evaluación de la Discapacidad , Discectomía/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Desplazamiento del Disco Intervertebral/complicaciones , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Polietileno , Estudios Prospectivos , Diseño de Prótesis , Radiculopatía/diagnóstico por imagen , Radiculopatía/etiología , Radiculopatía/cirugía , Radiografía , Reoperación/métodos , Enfermedades de la Médula Espinal/diagnóstico por imagen , Enfermedades de la Médula Espinal/etiología , Enfermedades de la Médula Espinal/cirugía , Fusión Vertebral/efectos adversosRESUMEN
BACKGROUND CONTEXT: The CHARITE artificial disc, a lumbar spinal arthroplasty device, was approved by the United States Food and Drug Administration in 2004 based on two-year safety and effectiveness data from a multicenter, prospective, randomized investigational device exemption (IDE) study. No long-term, randomized, prospective study on the CHARITE disc or any other artificial disc has been published to date. PURPOSE: The purpose of this study was to compare the safety and effectiveness at the five-year follow-up time point of lumbar total disc replacement using the CHARITE artificial disc (DePuy Spine, Raynham, MA) with that of anterior lumbar interbody fusion (ALIF) with BAK cages and iliac crest autograft, for the treatment of single-level degenerative disc disease from L4 to S1, unresponsive to nonoperative treatment. STUDY DESIGN/SETTING: Randomized controlled trial-five-year follow-up. PATIENT SAMPLE: Ninety CHARITE patients and 43 BAK patients. OUTCOME MEASURES: Self-reported measures: visual analog scale (VAS); validated Oswestry disability index (ODI version 1.0); Short-Form 36 Questionnaire, and patient satisfaction. Physiologic measures: radiographic range of motion, disc height, and segmental translation. Functional measures: work status. METHODS: Of the 375 subjects enrolled in the CHARITE IDE trial, 277 were eligible for the five-year study and 160 patients thereof completed the five-year follow-up. The completers included 133 randomized patients. Overall success was defined as improvement> or =15 pts in ODI vs. baseline, no device failure, absence of major complications, and maintenance or improvement of neurological status. Additional clinical outcomes included an ODI questionnaire as well as VAS, SF-36, and patient satisfaction surveys. Work status was tracked for all patients. Safety assessments included occurrence and severity of adverse events and device failures. Radiographic analyses such as index- and adjacent-level range of motion, segmental translation, disc height, and longitudinal ossification were also carried out. RESULTS: Overall success was 57.8% in the CHARITE group vs. 51.2% in the BAK group (Blackwelder's test: p=0.0359, Delta=0.10). In addition, mean changes from baseline for ODI (CHARITE: -24.0 pts vs. BAK: -27.5 pts), VAS pain scores (CHARITE: -38.7 vs. BAK: -40.0), and SF-36 questionnaires (SF-36 Physical Component Scores [PCS]: CHARITE: 12.6 pts vs. BAK: 12.3 pts) were similar across groups. In patient satisfaction surveys, 78% of CHARITE patients were satisfied vs. 72% of BAK patients. A total of 65.6% patients in the CHARITE group vs. 46.5% patients in the BAK group were employed full-time. This difference was statistically significant (p=0.0403). Long-term disability was recorded for 8.0% of CHARITE patients and 20.9% of BAK patients, a difference that was also statistically significant (p=0.0441). Additional index-level surgery was performed in 7.7% of CHARITE patients and 16.3% of BAK patients. Radiographic findings included operative and adjacent-level range of motion (ROM), intervertebral disc height and segmental translation. At the five-year follow-up, the mean ROM at the index level was 6.0 degrees for CHARITE patients and 1.0 degrees for BAK patients. Changes in disc height were also similar for both CHARITE and BAK patients (0.7 mm for both groups, p=0.9827). Segmental translation was 0.4 and 0.8mm in patients implanted with CHARITE at L4-L5 vs. L5-S1, respectively, and 0.1mm in BAK patients. CONCLUSIONS: The results of this five-year, prospective, randomized multicenter study are consistent with the two-year reports of noninferiority of CHARITE artificial disc vs. ALIF with BAK and iliac crest autograft. No statistical differences were found in clinical outcomes between groups. In addition, CHARITE patients reached a statistically greater rate of part- and full-time employment and a statistically lower rate of long-term disability, compared with BAK patients. Radiographically, the ROMs at index- and adjacent levels were not statistically different from those observed at two-years postsurgery.
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Artroplastia de Reemplazo/instrumentación , Artroplastia de Reemplazo/métodos , Desplazamiento del Disco Intervertebral/cirugía , Prótesis Articulares , Fusión Vertebral/métodos , Adulto , Artroplastia de Reemplazo/efectos adversos , Falla de Equipo , Femenino , Estudios de Seguimiento , Humanos , Disco Intervertebral/cirugía , Prótesis Articulares/efectos adversos , Vértebras Lumbares , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Rango del Movimiento Articular , Recuperación de la Función , Fusión Vertebral/efectos adversos , Fusión Vertebral/instrumentación , Resultado del Tratamiento , Estados Unidos , United States Food and Drug AdministrationRESUMEN
OBJECT: A secondary lumbar surgery at a previously surgically treated level is believed to result in minimal clinical improvement. The clinical results of the CHARITE Investigational Device Exemption (IDE) study were analyzed to assess the effect of previous surgery on clinical outcomes following either total disc replacement with the CHARITE device or anterior lumbar interbody fusion with a BAK cage and iliac crest autograft. METHODS: Patients with prior microdiscectomy, laminectomy, or minimal medial facetectomy were not excluded from enrollment in the CHARITE IDE study. Thus, the following 3 groups were analyzed: all patients treated with the CHARITE Artificial Disc, whether randomized or nonrandomized; only patients treated with CHARITE devices randomized against patients with BAK devices; and control patients with BAK devices. Each group was further subdivided based on the patients' medical history, whether they had undergone prior surgery (prior surgery group) or had not (no prior surgery group). For all groups, baseline demographics were collected and compared for any potential recruitment bias. Postoperative improvements based on Oswestry Disability Index (ODI), visual analog scale (VAS), and patient satisfaction scores were further collected and statistically analyzed. RESULTS: For all 3 groups, there were no statistical differences in clinical improvement from 3 months to 2 years postoperatively as measured using ODI and VAS scores between the subgroups (those who had prior surgery and those who did not). CONCLUSIONS: Patients indicated for 1-level lumbar arthroplasty with previous lumbar decompressive surgery can be expected to have similar clinical outcomes to patients undergoing arthroplasty without prior lumbar decompressive surgery. Similarly, candidates for anterior lumbar fusion with prior decompressive surgery may experience similar benefits from the surgical procedure as those without.
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Artroplastia de Reemplazo , Prótesis Articulares , Vértebras Lumbares , Reoperación , Enfermedades de la Columna Vertebral/cirugía , Adolescente , Adulto , Artroplastia de Reemplazo/efectos adversos , Artroplastia de Reemplazo/instrumentación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Satisfacción del Paciente , Factores de Tiempo , Resultado del TratamientoRESUMEN
OBJECT: Patient selection is perhaps the most important factor in successful lumbar surgery. In this study, the authors analyzed the clinical outcomes of patients enrolled in the CHARITE investigational device exemption (IDE) trial who underwent revision surgery after primary total disc replacement with CHARITE or an anterior lumbar interbody fusion (ALIF) with placement of a BAK cage and iliac crest autograft. This revision surgery was either a supplemental posterior lumbar fixation or a 360 degrees fusion. Statistical analysis was conducted to compare clinical success in patients who underwent revision surgery with those who did not. METHODS: The patients enrolled in the CHARITE IDE study were divided into 6 groups according to treatment and repeated operation status, and their Oswestry Disability Index (ODI) and visual analog scale (VAS) scores at the 2-year follow-up and at baseline were compared. The patients had received the following treatments by group: A) ALIF without reoperation; B) ALIF with conversion to 360 degrees fusion; C) arthroplasty (randomized) without repeated operation; D) arthroplasty with supplemental posterior lumbar fixation; E) arthroplasty (nonrandomized) without repeated operation; and F) arthroplasty (nonrandomized) with supplemental posterior lumbar fixation. Outcome scores in the groups of patients who required revision surgeries (Groups B, D, and F; 23 patients) were compared with the groups that did not require revision surgery (Groups A, C, and E; 299 patients). RESULTS: Patients who required revision surgery had a significantly lower level of clinical improvement than those who did not. The mean change in ODI score was -53.0% in Groups A, C, and E, but just -12.7% in Groups B, D, and F (p < 0.0001). The mean change in VAS score was -59.1% in Groups A, C, and E, compared to -23.4% in Groups B, D, and F (p < 0.0001). No significant differences were identified in analyzing absolute change in scores and the percentage change. A comparison of outcomes in patients who had undergone arthroplasty without reoperation (Groups C and E) with all patients who had undergone revision surgery (Groups B, D, and F) demonstrated similar results (p < 0.0001). CONCLUSIONS: The 7.1% of patients who underwent a secondary stabilization procedure had poor clinical improvement. This finding may indicate that if the alternative treatment had been the initial treatment, these patients would not have benefited, and further implies a 7.1% rate of imprecision in preoperative evaluation.
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Artroplastia de Reemplazo/métodos , Disco Intervertebral/cirugía , Vértebras Lumbares/cirugía , Selección de Paciente , Fusión Vertebral/métodos , Trasplante Óseo , Estudios de Cohortes , Personas con Discapacidad/clasificación , Estudios de Seguimiento , Humanos , Dimensión del Dolor , Reoperación , Fusión Vertebral/instrumentación , Resultado del TratamientoRESUMEN
OBJECT: One of the goals of lumbar arthroplasty is to restore and maintain range of motion (ROM) and to protect adjacent levels from abnormal motion, which may be a factor in transition syndrome following arthrodesis. In this study, in vitro ROM results were compared with in vivo, 2-year postoperative radiographic ROM evaluations. METHODS: Radiographs of patients enrolled in the CHARITE investigational device exemption study were analyzed at baseline and at 2 years postoperatively. The ROM in flexion/extension at the implanted and adjacent levels was measured, normalized, and compared with ROM results obtained using cadaver (in vitro) evaluations. RESULTS: Preoperative ROM distributions in patients enrolled for arthroplasty or fusion at the L4-5 level was as follows: 28% motion was observed at L3-4, 35% at L4-5 and 37% at L5-S1. Following a one-level arthroplasty at L4-5, the in vivo ROM distribution from L-3 to S-1 at the 2-year time point was 36% at L3-4, 30% at L4-5 and 35% at L5-S1. Following a one-level fusion with BAK and pedicle screws at L4-5, the in vivo ROM distribution from L-3 to S-1 at the 2-year time point was 45% at L3-4, 9% at L4-5 and 46% at L5-S1. CONCLUSIONS: The baseline as well as the 2-year in vivo data confirmed previously published in vitro data. One-level arthroplasty was shown herein to replicate the normal distribution of motion of the intact spine.
Asunto(s)
Artroplastia de Reemplazo/métodos , Disco Intervertebral/cirugía , Prótesis Articulares , Vértebras Lumbares/cirugía , Rango del Movimiento Articular/fisiología , Fusión Vertebral/métodos , Fenómenos Biomecánicos , Cadáver , Estudios de Cohortes , Estudios de Seguimiento , Humanos , Disco Intervertebral/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Docilidad , Estudios Prospectivos , Diseño de Prótesis , RadiografíaRESUMEN
BACKGROUND CONTEXT: Degenerative disc disease (DDD) is a cause of low back pain commonly requiring surgical intervention. The option of lumbar total disc replacement (TDR) represents an advance in the surgical treatment of DDD. However, new treatments, particularly those that include the use of new implants, may lead to increased costs to both hospitals and payers. Therefore, it is both necessary and appropriate to examine the potential costs associated with a new procedure such as total disc replacement compared with traditional treatments for a specific pathology. PURPOSE: To perform an economic analysis of lumbar TDR versus three different techniques for lumbar fusion. STUDY DESIGN/SETTING: A cost-minimization model. METHODS: An economic model examining hospital and payer cost perspectives was developed to compare costs of TDR with the CHARITE Artificial Disc to three spinal fusion procedures: anterior lumbar interbody fusion (ALIF) with iliac crest bone graft (ICBG); ALIF with INFUSE Bone Graft and LT-Cages, and instrumented posterior lumbar interbody fusion (IPLIF) with ICBG. The hospital perspective compares direct medical costs during the index hospitalization. The payer perspective considers direct medical costs of the index hospitalization and those incurred in the following two-year period. The model contains a Diagnostic Related Group (DRG) arm based strictly on DRG coding and payment, and a per-diem arm that includes a device carve-out cost and payment. RESULTS: In the DRG and per-diem arms of the model, compared with TDR, hospital costs are 12.0% higher for ALIF with ICBG, 36.5% higher for ALIF with INFUSE, and 36.5% higher for IPLIF. For payers, in the per-diem arm compared with TDR, ALIF with ICBG has 4.4% lower cost, whereas ALIF with INFUSE and IPLIF have costs of 16.1% and 27.1% higher, respectively. In the DRG arm compared with TDR, payer cost is 87.1% higher for ALIF with ICBG, 82.8% higher for ALIF with INFUSE, and 99.0% higher for IPLIF. CONCLUSIONS: The model shows that the overall economic effect of one-level TDR procedures on hospitals and payers is likely to be less than or at worse equivalent to one-level lumbar fusion procedures.
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Artroplastia/economía , Desplazamiento del Disco Intervertebral/economía , Desplazamiento del Disco Intervertebral/cirugía , Modelos Econométricos , Fusión Vertebral/economía , Grupos Diagnósticos Relacionados/economía , Gastos en Salud , Costos de Hospital , Humanos , Dolor de la Región Lumbar/economía , Dolor de la Región Lumbar/cirugía , Vértebras Lumbares/cirugía , Sistema de Pago Prospectivo , Prótesis e Implantes/economíaRESUMEN
STUDY DESIGN: A large case series of anterior revision surgery in patients who had complications following lumbar total disc replacement with the CHARITE artificial disc. OBJECTIVES: To analyze and discuss the etiology of implant-related complications and to present a strategy that can be applied to lumbar intervertebral disc prostheses in cases where anterior revision surgery is necessary. SUMMARY OF BACKGROUND DATA: This report represents the largest single-site, consecutive case series reported in the literature of anterior revision surgery following lumbar disc arthroplasty. METHODS: A total of 18 patients are included in this study. All patients required an anterior revision procedure for repositioning or removal of the prosthesis. The mean time to revision was 6 months (range, 9 days to 4 years). RESULTS: In 17 of 20 cases, implant removal was required and the patient was converted to a fusion. In 3 cases, primary revision of the CHARITE artificial disc was performed. Six revision cases were performed within the early postoperative period, defined as 7 to 14 days. All early cases were approached via reexploration of the original anterior midline retroperitoneal incision. Late revision was required in 14 cases, ranging from 3 weeks to 4 years following initial arthroplasty. A variety of surgical approaches were used in late revisions, including the lateral transpsoas approach at L3-L4 or L4-L5 (n = 5), expanded ipsilateral left retroperitoneal approach at L4-L5 (n = 2), contralateral right retroperitoneal approach at L5-S1 (n = 6), and transperitoneal approach (n = 1). Following 20 consecutive, anterior revision procedures, implant revision was successfully achieved in all cases. CONCLUSIONS: Total disc replacement implant revisions occur largely as a result of technical errors in positioning and sizing of the implant. In addition, adherence to strict patient selection criteria will eliminate many cases of implant failure. When necessary, anterior revision surgery can be performed safely when a strategic approach is used.
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Disco Intervertebral/cirugía , Vértebras Lumbares/cirugía , Prótesis e Implantes/efectos adversos , Implantación de Prótesis/métodos , Adulto , Anciano , Discectomía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Falla de Prótesis , Implantación de Prótesis/efectos adversos , Reoperación , Estudios Retrospectivos , Insuficiencia del TratamientoRESUMEN
BACKGROUND: Introduction of a new surgical technology may result in higher rates of adverse events compared with rates reported in the study performed to gain regulatory approval. The purpose of our study was to describe the incidence of reported adverse events during the first 18 months following US Food and Drug Administration (FDA) approval of the first lumbar arthroplasty device available in the United States and to discern data trends. METHODS: Reports of adverse events submitted to the FDA in patients receiving the Charité artificial disc were reviewed and pooled by similarity. We analyzed 135 medical device reports filed with the FDA regarding the Charité artificial disc between October 26, 2004, and April 26, 2006. Sixteen reports were excluded for lack of information regarding cause or because described events were vague or unrelated to the procedure. RESULTS: Rate of adverse events reported to the FDA as a percentage of devices of which the device manufacturer was aware had been dispensed at 6, 12, and 18 months following approval was 0.58%, 2.34%, and 2.13%, respectively. The adverse event reported most frequently through 18 months was anterior migration with reoperation (0.65%); other reported adverse events were, in decreasing order, sizing and malposition errors resulting in reoperation (0.36%), posterior element fracture resulting in reoperation (0.30%), major vascular injury requiring a blood transfusion (0.23%), and subsidence requiring reoperation (0.20%). Three non-device-related patient deaths were reported following FDA approval. The reported rate of sizing/malposition errors leading to reoperation of 0.36% was the same rate as that seen in the investigational device exemption (IDE) study of the Charité artificial disc. All other reported rates were lower than rates of the same events reported in the study. CONCLUSIONS: Medical device reporting is an important yet highly anecdotal and incomplete event-tracking process. However, it is the principal means available in the United States for obtaining information on the clinical performance of a device after its approval for sale and does provide some data, albeit imperfect, in this regard. The cumulative medical device reports through the 18 months following FDA approval, measured against the number of devices dispensed, suggests a rate of adverse events that either tracks or is somewhat less than that reported in the IDE study. This suggests that a repeat of the "cage rage," a "lumbar arthroplasty rage," has not yet occurred.
RESUMEN
BACKGROUND: Previous reports of lumbar total disc replacement (TDR) have described significant complications. The US Food and Drug Administration (FDA) investigational device exemption (IDE) study of the Charité artificial disc represents the first level I data comparison of TDR to fusion. METHODS: In the prospective, randomized, multicenter IDE study, patients were randomized in a 2:1 ratio, with 205 patients in the Charité group and 99 patients in the control group (anterior lumbar interbody fusion [ALIF] with BAK cages). Inclusion criteria included confirmed single-level degenerative disc disease at L4-5 or L5-S1 and failure of nonoperative treatment for at least 6 months. Complications were reported throughout the study. RESULTS: The rate of approach-related complications was 9.8% in the investigational group and 10.1% in the control group. The rate of major neurological complications was similar between the 2 groups (investigational = 4.4%, control = 4.0%). There was a higher rate of superficial wound infection in the investigational group but no deep wound infections in either group. Pseudarthrosis occurred in 9.1% of control group patients. The rate of subsidence in the investigational group was 3.4%. The reoperation rate was 5.4% in the investigational group and 9.1% in the control group. CONCLUSIONS: The incidence of perioperative and postoperative complications for lumbar TDR was similar to that of ALIF. Vigilance is necessary with respect to patient indications, training, and correct surgical technique to maintain TDR complications at the levels experienced in the IDE study.
RESUMEN
BACKGROUND: Several lumbar disc prostheses are being developed with the goal of preserving mobility in patients with degenerative disc disease. The disadvantage of lumbar artificial disc replacement (ADR) compared with anterior interbody fusion (ALIF) is the increased potential for displacement or component failure. Revision or removal of the device is complicated by adherence of the aorta, iliac vessels, and the ureter to the operative site. Because of these risks of anterior lumbar procedures, vascular surgeons usually provide access to the spine. We report our experience with secondary exposure of the lumbar spine for revision or explantation of the Charité disc prosthesis. METHODS: Between January 2001 and May 2006, 19 patients with prior implantation of Charité Artificial Discs required 21 operations for repositioning or removal of the device. Two patients had staged removal of prostheses at two levels. One patient had simultaneous explantation at two levels. The mean age was 49 years (range, 31 to 69 years; 56% men, 42% women). The initial ADR was performed at our institution in 14 patients (74%). The mean time from implantation to reoperation was 7 months (range, 9 days to 4 years). The levels of failure were L3-4 in one, L4-5 in nine, and L5-S1 in 12. RESULTS: The ADR was successfully removed or revised in all patients that underwent reoperation. Three of the 12 procedures at L5-S1 were performed through the same retroperitoneal approach as the initial access. One of these three, performed after a 3-week interval, was converted to a transperitoneal approach because of adhesions. The rest of the L5-S1 prostheses were exposed from a contralateral retroperitoneal approach. Four of the L4-5 prostheses were accessed from the original approach and five from a lateral, transpsoas exposure (four left, one right). The only explantation at L3-4 was from a left lateral transpsoas approach. Nineteen of the 22 ADR were converted to ALIF. Two revisions at L5-S1 involved replacement of the entire prosthesis. One revision at L4-5 required only repositioning of an endplate. Access-related complications included, in one patient each, iliac vein injury, temporary retrograde ejaculation, small-bowel obstruction requiring lysis, and symptomatic, large retroperitoneal lymphocele. There were no permanent neurologic deficits, deep vein thromboses, or deaths. CONCLUSIONS: Owing to vascular and ureteral fixation, anterior exposure of the lumbar spine for revision or explantation of the Charité disc replacement should be performed through an alternative approach unless the procedure is performed < or = 2 weeks of the index procedure. The L5-S1 level can be accessed through the contralateral retroperitoneum. Reoperation at L3-4 and L4-5 usually requires explantation and fusion that is best accomplished by way of a lateral transpsoas exposure.
Asunto(s)
Remoción de Dispositivos , Disco Intervertebral/cirugía , Vértebras Lumbares/cirugía , Procedimientos Ortopédicos , Enfermedades de la Columna Vertebral/cirugía , Adulto , Anciano , Europa (Continente) , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Ortopédicos/efectos adversos , Procedimientos Ortopédicos/instrumentación , Diseño de Prótesis , Implantación de Prótesis/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto , Reoperación , Fusión Vertebral/efectos adversos , Fusión Vertebral/métodos , Factores de Tiempo , Resultado del Tratamiento , Estados UnidosRESUMEN
STUDY DESIGN: A prospective, randomized, multicenter, Food and Drug Administration regulated Investigational Device Exemption (IDE) clinical trial. OBJECTIVES: To discern whether there is a correlation between surgical volume and clinical outcomes, as well as the complication rate and perioperative data points, for lumbar total disc replacement. To examine the early experience for lumbar total disc replacement as part of an IDE study. SUMMARY OF BACKGROUND DATA: To our knowledge, an analysis of the effect of surgical volume has not been performed for any spine surgical procedure. Prior reports of the early experience with lumbar total disc replacement consist of retrospective reviews with nonspecific indications. METHODS: An analysis was performed of the Food and Drug Administration IDE Study of the Charité Artificial Disc (DePuy Spine, Inc., Raynham, MA). Patients enrolled in the control group were omitted from the analysis. Up to 5 nonrandomized cases (representing the early experience) were performed at each site before beginning the randomized arm of the study. There were 3 comparisons performed: nonrandomized cases (71) versus randomized cases (205); randomized cases performed by high-enrolling surgeons versus low-enrolling surgeons; and randomized cases at high-volume institutions versus low-volume institutions. RESULTS: The high-enrolling groups had a significantly lower mean hospital stay and operating time compared to the low-enrolling groups (P < 0.05). High-enrolling surgeons and institutions showed significantly shorter operating times, length of hospital stay, and complication rates. High-enrolling surgeons had significantly fewer device failures and cases of neurologic deterioration. Mean operating time and hospital stay were significantly lower in the randomized group (P < 0.05) compared to the nonrandomized group. Blood loss and approach-related complications were similar between the 2 groups. Device failure requiring removal was 4.2% in the nonrandomized group and 1.5% in the randomized group. CONCLUSIONS: Surgeons and institutions with a high volume of lumbar total disc replacement cases have a reduction in key perioperative and postoperative parameters that provide a clinical and/or economic benefit. Surgeons may expect longer hospital stays, higher blood loss, and a higher rate of certain complications in their early experience with total disc replacement procedures, but there was no effect on clinical outcomes.
Asunto(s)
Disco Intervertebral , Prótesis e Implantes , Implantación de Prótesis/estadística & datos numéricos , Enfermedades de la Columna Vertebral/cirugía , Adolescente , Adulto , Pérdida de Sangre Quirúrgica/estadística & datos numéricos , Aprobación de Recursos , Femenino , Humanos , Tiempo de Internación/estadística & datos numéricos , Vértebras Lumbares , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Estudios Prospectivos , Resultado del TratamientoRESUMEN
STUDY DESIGN: A prospective, randomized, multicenter, FDA-regulated Investigational Device Exemption clinical trial. OBJECTIVES: To analyze the incidence of, and reasons for, reoperation in all patients (treatment and control) enrolled in the IDE study. SUMMARY OF BACKGROUND DATA: This is the first report of the incidence and nature of reoperations following lumbar TDR as part of a controlled, prospective, multicenter trial. METHODS: A total of 688 patients meeting the inclusion and exclusion criteria were enrolled in one of three arms of the study at 14 centers across the United States. This cohort includes 71 nonrandomized cases, 205 randomized cases, and 313 continued access cases, all receiving the CHARITE Artificial Disc, as well as 99 randomized cases in the control group (ALIF with threaded fusion cages and autograft). A detailed analysis was performed of clinical chart notes, operative notes, and adverse event reports for all patients requiring reoperation following their index surgery. RESULTS: Of the 589 patients with TDR, 52 (8.8%) required reoperation. Of the 99 patients with lumbar fusion, 10 (10.1%) required reoperation, and an additional 2 required surgery for adjacent level disease (P = 0.7401). There were 24 TDR patients who underwent a repeated anterior retroperitoneal approach, with 22 (91.7%) having had a successful removal of the prosthesis. Seven of the 24 TDR prostheses requiring removal were revised to another CHARITE Artificial Disc. The mean time to reoperation in all patients was 9.7 months. A total of 29 patients (4.9%) in the TDR group required posterior instrumentation and fusion as did 10 (10.1%) in the control group (P = 0.0562). At 2 years or more follow-up, 93.9%(553/589 = 93.9%) of patients receiving TDR with the CHARITE Artificial Disc had a successfully functioning prosthesis with a mean of over 7 degrees of flexion-extension mobility. CONCLUSIONS: Lumbar TDR with the CHARITE Artificial Disc did not preclude any further procedures at the index level during primary insertion, with nearly one third being revisable to a new motion-preserving prosthesis and just over two thirds being successfully converted to ALIF and/ or posterior pedicle screw arthrodesis, the original alternative procedure.
Asunto(s)
Desplazamiento del Disco Intervertebral/epidemiología , Desplazamiento del Disco Intervertebral/cirugía , Vértebras Lumbares/cirugía , Prótesis e Implantes , Adulto , Femenino , Humanos , Incidencia , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Masculino , Estudios Prospectivos , Prótesis e Implantes/efectos adversos , Radiografía , Reoperación/efectos adversos , Análisis de Supervivencia , Estados Unidos/epidemiologíaRESUMEN
STUDY DESIGN: A prospective, randomized, multicenter, Food and Drug Administration-regulated, investigational device exemption clinical trial. OBJECTIVES: To compare the safety and effectiveness of lumbar total disc replacement (TDR) with the CHARITE artificial disc (DePuy Spine, Raynham, MA) to anterior lumbar interbody fusion for the treatment of single-level degenerative disc disease from L4-S1 unresponsive to nonoperative treatment. In addition, to evaluate the radiographic outcomes of lumbar artificial disc replacement at either L4-L5 or L5-S1 with the CHARITE artificial disc as compared to anterior lumbar interbody fusion with cylindrical cages and iliac crest bone graft; and to determine if a correlation exists between clinical outcomes and surgical accuracy of TDR placement within the disc space. SUMMARY OF BACKGROUND DATA: Prior investigators have reported excellent radiographic results with the CHARITE artificial disc for the treatment of lumbar degenerative disc disease. These encouraging results are the product of retrospective reviews without a control. Very few studies have reported on the segmental motion of an intervertebral level implanted with an artificial disc, and no studies have reported a correlation of radiographic and clinical outcomes. METHODS: A prospective, randomized, multicenter, US Food and Drug Administration, investigational device exemption study with 24-month follow-up was performed at 14 centers throughout the United States. A total of 304 subjects were randomized in a 2:1 ratio, with 205 in the investigational group (TDR with the CHARITE artificial disc) and 99 in the control group (anterior lumbar interbody fusion with BAK cages and iliac crest bone graft). A total of 71 TDR training cases were performed (up to 5 at each site) before randomization beginning at each site. Plain radiographs were analyzed for each subject in both groups regarding range of motion (ROM) in flexion/extension, restoration of disc space height, and subsidence. Prosthesis placement in the coronal and midsagittal planes was analyzed for the 276 patients with TDR. Correlations were performed between prosthesis placement and clinical outcomes. RESULTS: Patients in the investigational group had a 13.6% mean increase, and those in the control group an 82.5% decrease in mean flexion/extension ROM at 24 months postoperatively compared to baseline. Patients in the investigational group had significantly better restoration of disc height than the control group (P < 0.05). There was significantly less subsidence in the investigational group compared to the control group (P < 0.05). The surgical technical accuracy of CHARITE artificial disc placement was divided into 3 groups: I, ideal (83%); II, suboptimal (11%); and III, poor (6%), and correlated with clinical outcomes. The flexion/extension ROM and prosthesis function improved with the surgical technical accuracy of radiographic placement (P = 0.003). CONCLUSIONS: Preoperative ROM in flexion/extension was restored and maintained in patients receiving a TDR. TDR with the CHARITE artificial disc resulted in significantly better restoration of disc space height, and significantly less subsidence than anterior interbody fusion with BAK cages. Clinical outcomes and flexion/extension ROM correlated with surgical technical accuracy of CHARITE artificial disc placement. In the majority of cases, placement of the CHARITE artificial disc was ideal.
Asunto(s)
Desplazamiento del Disco Intervertebral/cirugía , Disco Intervertebral , Vértebras Lumbares/cirugía , Prótesis e Implantes , Implantación de Prótesis/normas , Fusión Vertebral , Adulto , Femenino , Estudios de Seguimiento , Humanos , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/fisiología , Masculino , Persona de Mediana Edad , Movimiento , Estudios Prospectivos , Implantación de Prótesis/métodos , Radiografía , Rango del Movimiento Articular , Resultado del Tratamiento , Estados Unidos , United States Food and Drug AdministrationRESUMEN
STUDY DESIGN: A prospective, randomized, multicenter, Food and Drug Administration-regulated Investigational Device Exemption clinical trial. OBJECTIVES: The purpose of this study was to compare the safety and effectiveness of lumbar total disc replacement, using the CHARITE artificial disc (DePuy Spine, Raynham, MA), with anterior lumbar interbody fusion, for the treatment of single-level degenerative disc disease from L4-S1 unresponsive to nonoperative treatment. SUMMARY OF BACKGROUND DATA: Reported results of lumbar total disc replacement have been favorable, but studies have been limited to retrospective case series and/or small sample sizes. METHODS: Three hundred four (304) patients were enrolled in the study at 14 centers across the United States and randomized in a 2:1 ratio to treatment with the CHARITE artificial disc or the control group, instrumented anterior lumbar interbody fusion. Data were collected pre- and perioperatively at 6 weeks and at 3, 6, 12, and 24 months following surgery. The key clinical outcome measures were a Visual Analog Scale assessing back pain, the Oswestry Disability Index questionnaire, and the SF-36 Health Survey. RESULTS: Patients in both groups improved significantly following surgery. Patients in the CHARITE artificial disc group recovered faster than patients in the control group. Patients in the CHARITE artificial disc group had lower levels of disability at every time interval from 6 weeks to 24 months, compared with the control group, with statistically lower pain and disability scores at all but the 24 month follow-up (P < 0.05). At the 24-month follow-up period, a significantly greater percentage of patients in the CHARITE artificial disc group expressed satisfaction with their treatment and would have the same treatment again, compared with the fusion group (P < 0.05). The hospital stay was significantly shorter in the CHARITE artificial disc group (P < 0.05). The complication rate was similar between both groups. CONCLUSIONS: This prospective, randomized, multicenter study demonstrated that quantitative clinical outcome measures following lumbar total disc replacement with the CHARITE artificial disc are at least equivalent to clinical outcomes with anterior lumbar interbody fusion. These results support earlier reports in the literature that total disc replacement with the CHARITE artificial disc is a safe and effective alternative to fusion for the surgical treatment of symptomatic disc degeneration in properly indicated patients. The CHARITE artificial disc group demonstrated statistically significant superiority in two major economic areas, a 1-day shorter hospitalization, and a lower rate of reoperations (5.4% compared with 9.1%). At 24 months, the investigational group had a significantly higher rate of satisfaction (73.7%) than the 53.1% rate of satisfaction in the control group (P = 0.0011). This prospective randomized multicenter study also demonstrated an increase in employment of 9.1% in the investigational group and 7.2% in the control group.
Asunto(s)
Desplazamiento del Disco Intervertebral/cirugía , Disco Intervertebral , Vértebras Lumbares/cirugía , Prótesis e Implantes , Fusión Vertebral , Adulto , Evaluación de la Discapacidad , Empleo , Femenino , Estudios de Seguimiento , Humanos , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Dolor de la Región Lumbar/tratamiento farmacológico , Dolor de la Región Lumbar/cirugía , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Narcóticos/administración & dosificación , Dimensión del Dolor , Satisfacción del Paciente , Estudios Prospectivos , Diseño de Prótesis , Radiografía , Resultado del Tratamiento , Estados Unidos , United States Food and Drug AdministrationRESUMEN
To preserve segmental lumbar motion and to prevent adjacent segment disease, there has been a growing enthusiasm for the use of intervertebral disc prosthesis as an alternative to segmental lumbar fusion. To date, more than 100-disc prostheses have been designed, but only 10 prostheses have been approved and implanted in humans. The Charité Artificial Disc has had the longest clinical follow-up with more than 5000 implantations in over 30 countries and reported > 10-year satisfactory results.
Asunto(s)
Artroplastia de Reemplazo/métodos , Disco Intervertebral/cirugía , Prótesis Articulares , Vértebras Lumbares/cirugía , Adolescente , Adulto , Artroplastia de Reemplazo/instrumentación , Electromiografía/métodos , Femenino , Humanos , Disco Intervertebral/patología , Vértebras Lumbares/patología , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Cuidados Preoperatorios , Pronóstico , Diseño de Prótesis , Rango del Movimiento Articular/fisiología , Recuperación de la Función , Medición de Riesgo , Resultado del TratamientoRESUMEN
Spinal deformity has classically and historically been studied by those in the discipline of orthopedic surgery. This may be attributable to the orthopedic interventionalists' experience with osseous fixation for long-bone and other skeletal fractures. Neurosurgeons have maintained a long-standing interest in complex cervical spinal disorders, and their interest in the larger field of complex spinal deformity has been expanding. An understanding of spinal deformity disorders, biomechanics, bone biology, and metallurgy is necessary before clinical, teaching, and research activities can be undertaken within neurosurgery. The authors describe basic and advanced concepts of spinal deformity management with cases to illustrate teaching points.
Asunto(s)
Neurocirugia , Rol del Médico , Curvaturas de la Columna Vertebral/cirugía , Fenómenos Biomecánicos , Remodelación Ósea/fisiología , Diagnóstico por Imagen , Humanos , Curvaturas de la Columna Vertebral/diagnóstico , Curvaturas de la Columna Vertebral/etiología , Curvaturas de la Columna Vertebral/fisiopatologíaRESUMEN
OBJECT: Arthrodesis is the gold standard for surgical treatment of lumbar degenerative disc disease (DDD). Solid fusion, however, can cause stress and increased motion in the segments adjacent to the fused level. This may initiate and/or accelerate the adjacent-segment disease process. Artificial discs are designed to restore and maintain normal motion of the lumbar intervertebral segment. Restoring and maintaining normal motion of the segment reduces stresses and loads on adjacent level segments. A US Food and Drug Administration Investigational Device Exemptions multicentered study of the Charité artificial disc was completed. The control group consisted of individuals who underwent anterior lumbar interbody fusion involving BAK cages and iliac crest bone graft. This is the first report of Class I data in which a lumbar artificial disc is compared with lumbar fusion. METHODS: Of 304 individuals enrolled in the study, 205 were randomized to the Charité disc-treated group and 99 to the BAK fusion-treated (control) group. Neurological status was equivalent between the two groups at 6, 12, and 24 months postoperatively. The number of patients with major, minor, or other neurological complications was equivalent. There was a greater incidence of both major and minor complications in the BAK fusion group at 0 to 42 days postoperatively. Compared with data reported in the lumbar fusion literature, the Charité disc-treated patients had equivalent or better mean changes in visual analog scale and Oswestry Disability Index scores. CONCLUSIONS: The Charité artificial disc is safe and effective for the treatment of single-level lumbar DDD, resulting in no higher incidence of neurological complications compared with BAK-assisted fusion and leading to equivalent or better outcomes compared with those obtained in the control group and those reported in the lumbar fusion literature.
Asunto(s)
Discectomía , Prótesis Articulares , Vértebras Lumbares/cirugía , Complicaciones Posoperatorias , Fusión Vertebral , Fenómenos Biomecánicos , Evaluación de la Discapacidad , Discectomía/efectos adversos , Estudios de Seguimiento , Humanos , Hipoestesia/etiología , Prótesis Articulares/efectos adversos , Dimensión del Dolor , Parestesia/etiología , Satisfacción del Paciente , Estudios Prospectivos , Diseño de Prótesis , Rango del Movimiento Articular/fisiología , Reflejo/fisiología , Enfermedades de la Columna Vertebral/cirugía , Fusión Vertebral/efectos adversos , Fusión Vertebral/instrumentación , Resultado del TratamientoRESUMEN
STUDY DESIGN: A description of a novel surgical approach to the lumbar spine and a prospective evaluation of the early surgical outcomes. OBJECTIVES: Describe the early postoperative results and the operative technique of a new, minimally invasive transpsoas approach for anterior fusion of the lumbar spine that minimizes the risk to large vessels and other critical structures. SUMMARY OF BACKGROUND DATA: Standard anterior endoscopic approaches to the lumbar spine require mobilization of the great vessels and sympathetic plexus. Vascular injury and retrograde ejaculation are complications clearly associated with this approach. A retroperitoneal, transpsoas approach to the lumbar spine may reduce these risks. METHODS: From 1996 to 2002, 21 patients (13 females, 8 males; mean age 50.0 years) underwent an endoscopic, retroperitoneal transpsoas approach for exposure of the lumbar spine. Surgical indications included discogenic pain in 14 patients, spinal instability at a level adjacent to a previous fusion in 3 patients, and progressive degenerative scoliosis in 4 patients. Data were reviewed to document the early postoperative results for this procedure. Illustrations were created to clearly describe this approach. RESULTS: Average operative time for the single level cases was 149 minutes (range 120-170 minutes); blood loss was 150 cc (range 50-650); postoperative hospital stay was 4.1 days. At long-term follow-up, visual analogue scale scores had decreased an average of 5.9. Mean follow-up was 3.1 years (range 2 months-6.0 years). Six patients (30%) experienced paresthesias in the groin/thigh region. Five of these same patients also complained of groin/thigh pain (27%). Two patients had symptoms that lasted longer than 1 month. One patient was converted to a mini-open lateral approach. There were no vascular injuries. CONCLUSIONS: Early results show the endoscopic lateral transpsoas approach to the lumbar spine to be a safe, minimally invasive method for anterior fusion of the first through the fourth lumbar vertebrae. Although there is a risk of groin/thigh numbness or pain, and these symptoms are mostly transient. This approach allows for exposure of the lumbar spine without mobilization of the great vessels or sympathetic plexus.
Asunto(s)
Endoscopía/métodos , Vértebras Lumbares/cirugía , Fusión Vertebral/métodos , Adulto , Anciano , Endoscopios , Femenino , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos , Complicaciones Posoperatorias , Músculos Psoas/cirugía , RadiografíaRESUMEN
OBJECT: The authors evaluated cervical spine radiographs to determine sagittal alignment in patients who underwent one- or two-level arthroplasty with the Bryan cervical artificial disc prosthesis. METHODS: The curvature of the surgically treated spinal segments and the overall curvature of the cervical spine were evaluated in 13 patients who underwent 16 cervical arthroplasty device placements. Preoperative and postoperative lateral radiographs were reviewed and compared using standardized techniques for measuring spinal curvature. Patients who underwent a single-level cervical arthroplasty had a 4.7 degrees mean reduction (p < 0.05) in lordosis after cervical artificial disc replacement. The three patients who underwent two-level cervical arthroplasty had no significant changes in the sagittal alignment. CONCLUSIONS: Patients who underwent arthroplasty with a Bryan cervical artificial disc had a focal loss of lordosis (that is, kyphosis) at the treated levels after single-level procedures. Nevertheless, there was no significant change in the overall sagittal curvature of the cervical spine after single-level artificial disc replacements. The patients who underwent two-level artificial disc placement had no significant changes in lordosis at the treated levels or in the overall curvature. The likely source of this outcome appears to be the endplate milling procedures that reorient the vertebral endplates.