BlueCross and BlueShield of Montana Medical Policy/Codes
Artificial Intervertebral Disc
Chapter: Surgery: Procedures
Current Effective Date: November 15, 2013
Original Effective Date: May 09, 2008
Publish Date: November 15, 2013
Revised Dates: March 1, 2010; August 15, 2011; November 08, 2012; November 15, 2013
Description

Cervical Artificial Intervertebral Disc

Several prosthetic devices are currently available for artificial intervertebral disc arthroplasty (AIDA) of the cervical spine. AIDA is proposed as an alternative to anterior cervical discectomy and fusion (ACDF) for patients with symptomatic cervical degenerative disc disease (DDD).

Background

Cervical DDD is a manifestation of spinal spondylosis that causes deterioration of the intervertebral discs of the cervical spine. Symptoms of cervical DDD include arm pain, weakness, and paresthesias associated with cervical radiculopathy. Disc herniation, osteophytes, kyphosis, or instability that compress the spinal cord can result in myelopathy, which is manifested by subtle changes in gait or balance, and in severe cases leads to weakness in the arms or legs, and numbness of the arms or hands. The prevalence of DDD secondary to cervical spondylosis increases with age. An estimated 60% of individuals older than 40 years have radiographic evidence of cervical DDD. By age 65, some 95% of men and 70% of women have at least one degenerative change evident at radiographic examination. It is estimated that approximately 5 million adults in the United States are disabled to an extent by spine-related disorders, although only a small fraction of those are clear candidates for spinal surgery. Cervical DDD is initially treated conservatively using noninvasive measures (e.g., rest, heat, ice, analgesics, anti-inflammatory agents, exercise). If symptoms do not improve or resolve after 6 weeks or more, or if symptoms progress, surgical intervention may be indicated. Candidates for surgical intervention have chronic pain or neurologic symptoms secondary to cervical DDD and no contraindications for the procedure.

ACDF is currently considered the definitive surgical treatment for symptomatic DDD of the cervical spine. The goals of ACDF are to relieve pressure on the spinal nerves (decompression) and to restore spinal column alignment and stability. Resolution of pain and neurologic symptoms may be expected in 80% to 100% of ACDF patients. ACDF involves an anterolateral surgical approach, decompression of the affected spinal level, discectomy, and emplacement of either autograft or allograft bone in the prepared intervertebral space to stimulate healing and eventual fusion between the vertebral endplates. A metal anterior cervical plate is attached to the adjoining vertebral bodies to stabilize the fusion site, maintain neck lordosis, and reduce the need for prolonged postoperative brace application that is needed following ACDF without an anterior plate. The choice of bone material for interbody fusion in ACDF has important clinical implications. Allograft bone has several drawbacks, including a small (albeit, unproven) risk of infectious disease transmission; possible immunologic reaction to the allograft, and possible limited commercial availability of appropriate graft material. In contrast, the use of autograft bone in ACDF has potentially substantial morbidities at the harvest site, generally the iliac crest. These morbidities include moderate-to-severe, sometimes prolonged pain; deep infection; adjacent nerve and artery damage; and increased risk of stress fracture. Although there may be slight differences between autograft and allograft sources in the postoperative rate of union, clinical studies demonstrate similar rates of postoperative fusion (90–100%) and satisfactory outcomes for single-level, anterior-plated ACDF, using either bone source. Thus, the choice of graft material involves a trade-off between the risks specific to autograft harvest versus those specific to use of allograft material. Biomechanical modeling studies have suggested that altered adjacent segment kinematics following fusion may lead to adjacent-level DDD; however, the clinical relevance of these changes has not been established.

AIDA is proposed as an alternative to ACDF for patients with symptomatic cervical DDD. In AIDA, an artificial disc device is secured in the prepared intervertebral space rather than in bone. An anterior plate is not placed to stabilize the adjacent vertebrae, and postsurgical external orthosis is usually not required. It is hypothesized that AIDA will maintain anatomical disk space height, normal segmental lordosis, and physiological motion patterns at the index and adjacent cervical levels. The potential to reduce the risk of adjacent-level DDD above or below a fusion site has been the major rationale driving device development and use. Disc arthroplasty and ACDF for single-level disease have very similar surgical indications, primarily unremitting pain due to radiculopathy or myelopathy, weakness in the extremities, or paresthesia. However, the chief complaint in AIDA candidates should be radicular or myelopathic symptoms in the absence of significant spondylosis. Patients with advanced spondylosis or hard disc herniations have a separate pathologic condition and require a different surgical approach.

Regulatory Status

The Prestige ST Cervical Disc (Medtronic) received U.S. Food and Drug Administration (FDA) premarket application (PMA) approval as a Class III device on July 16, 2007. The Prestige ST Cervical Disc is composed of stainless steel and is indicated in skeletally mature patients for reconstruction of the disc from C3-C7 following single-level discectomy. The device is implanted via an open anterior approach. Intractable radiculopathy and/or myelopathy should be present, with at least one of the following items producing symptomatic nerve root and/or spinal cord compression as documented by patient history (e.g., pain [neck and/or arm pain], functional deficit, and/or neurologic deficit) and radiographic studies (e.g., computed tomography [CT], magnetic resonance imaging [MRI], x-rays): herniated disc and/or osteophyte formation. The FDA has required the Prestige disc manufacturer to conduct a 7-year post-approval clinical study of the safety and function of the device and a 5-year enhanced surveillance study of the disc to more fully characterize adverse events in a broader patient population.

Another disc arthroplasty product, the ProDisc-C® (Synthes Spine) received FDA PMA approval in December 2007. As with the Prestige ST Cervical Disc, the FDA approval of ProDisc-C is conditional on 7-year follow-up of the 209 subjects included in the noninferiority trial (discussed in Rationale section), 7-year follow-up on 99 continued access subjects, and a 5-year enhanced surveillance study to more fully characterize adverse events when the device is used under general conditions of use. The post-approval study reports are to be delivered to the FDA annually.

The Bryan Cervical Disc (Medtronic Sofamor Danek) consists of 2 titanium-alloy shells encasing a polyurethane nucleus and has been available outside of the United States since 2002. The Bryan Cervical Disc was approved by the FDA in May 2009 for treatment using an anterior approach of single-level cervical DDD defined as any combination of the following: disc herniation with radiculopathy, spondylotic radiculopathy, disc herniation with myelopathy, or spondylotic myelopathy resulting in impaired function and at least one clinical neurologic sign associated with the cervical level to be treated, and necessitating surgery as demonstrated using CT, myelography and CT, and/or MRI. Patients receiving the Bryan cervical disc should have failed at least 6 weeks of non-operative treatment prior to implantation of the Bryan cervical disc. As a condition for approval of this device, the FDA required the manufacturer to extend its follow-up of enrolled subjects to 10 years after surgery. The study will involve the investigational and control patients from the pivotal investigational device exemption (IDE) study arm, as well as the patients who received the device as part of the continued access study arm. In addition, the manufacturer must perform a 5-year enhanced surveillance study of the BRYAN® Cervical Disc to more fully characterize adverse events when the device is used in a broader patient population.

A number of other devices are under study in FDA IDE trials in the United States, including: Prestige® LP (Medtronic); Porous Coated Motion (PCM®)/Intervertebral Dynamic Disc Spacer (NuVasive); Kineflex C® Cervical Artificial Disc Implant (Spinal Motion); CerviCore™ Intervertebral Disc (Stryker); Discover (DePuy); Mobi-C (LDR spine); NeoDisc™ (NuVasive); and Secure®-C (Globus Medical).

Lumbar Artificial Intervertebral Disc

Total disc replacement, using an artificial intervertebral disc designed for the lumbar spine, is proposed as an alternative to fusion in patients with persistent and disabling nonradicular low back pain.

Background

When conservative treatment of degenerative disc disease fails, a common surgical approach is spinal fusion; more than 200,000 spinal fusions are performed each year. However, the outcomes of spinal fusion have been controversial over the years, in part due to the difficulty in determining if a patient's back pain is related to DDD and in part due to the success of the procedure itself. In addition, spinal fusion alters the biomechanics of the back, potentially leading to premature disc degeneration at adjacent levels, a particular concern for younger patients. During the past 30 years, a variety of artificial intervertebral discs have been investigated as an alternative approach to fusion. This approach, also referred to as total disc replacement or spinal arthroplasty, is intended to maintain motion at the operative level once the damaged disc has been removed and to maintain the normal biomechanics of the adjacent vertebrae.

Potential candidates for artificial disc replacement have chronic low back pain attributed to DDD, lack of improvement with non-operative treatment, and none of the contraindications for the procedure, which include multilevel disease, spinal stenosis, or spondylolisthesis, scoliosis, previous major spine surgery, neurologic symptoms, and other minor contraindications. These contraindications make artificial disc replacement suitable for a subset of patients in whom fusion is indicated. Patients who require procedures in addition to fusion, such as laminectomy and/or decompression, are not candidates for the artificial disc.

Use of a motion-preserving artificial disc increases the potential for a variety of types of implant failure. These include device failure (device fracture, dislocation, or wear), bone-implant interface failure (subsidence, dislocation-migration, vertebral body fracture), and host response to the implant (osteolysis, heterotopic ossification, and pseudotumor formation).

Regulatory Status

While artificial intervertebral discs in the lumbar spine have been used internationally for more than 10 years, only 2 devices (Charité® and ProDisc®-L) have received approval from the FDA. Because the long-term safety and effectiveness of these devices were not known, approval was contingent on completion of postmarketing studies. The Charité (DePuy) and ProDisc-L (Synthes Spine) devices are indicated for spinal arthroplasty in skeletally mature patients with DDD at one level; Charité is approved for use in levels L4–S1, and the ProDisc-L is approved for use in levels L3–S1. DDD is defined as discogenic back pain with degeneration of the disc confirmed by patient history and radiographic studies. The INMOTION® lumbar artificial disc (DePuy Spine) is a modification of the Charité® device. Production of the Charité® disc was stopped in 2010. Other devices are currently under investigation in the U.S. as part of the FDA process of approval, including the FlexiCore (Stryker Spine), Maverick (Medtronic), and Activ-L™ (Aesculap) devices.

Policy

Each benefit plan, summary plan description or contract defines which services are covered, which services are excluded, and which services are subject to dollar caps or other limitations, conditions or exclusions. Members and their providers have the responsibility for consulting the member's benefit plan, summary plan description or contract to determine if there are any exclusions or other benefit limitations applicable to this service or supply. If there is a discrepancy between a Medical Policy and a member's benefit plan, summary plan description or contract, the benefit plan, summary plan description or contract will govern.

Coverage

Cervical Artificial Intervertebral Disc

Cervical artificial intervertebral disc, using a disc that has the approval of the U.S. Food and Drug Administration (FDA), may be considered medically necessary when ALL of the following criteria are met:

  1. Disc will be used for single-level reconstruction following cervical discectomy within the C3-C7 region; AND
  2. Patient has intractable radiculopathy and/or myelopathy due to herniated disc or osteophyte formation; AND
  3. Patient has failed at least six weeks of conservative therapy; AND
  4. Symptomatic nerve root and/or spinal cord compression are documented by ALL the following:
    • Neck and/or arm pain; and
    • Functional and/or neurological deficit; and
    • Radiographic imaging (e.g., Computed Tomography (CT), Magnetic Resonance Imaging (MRI), x-rays, etc.).

Artificial intervertebral cervical disc is considered experimental, investigational and unproven for all other indications, including multi-level use, whether done simultaneously or at different times.

Lumbar Artificial Intervertebral Disc

Lumbar artificial intervertebral disc, using a disc that has the approval of the U.S. Food and Drug Administration (FDA), may be considered medically necessary for patients who meet ALL of the following criteria:

  1. Skeletally mature; AND
  2. Degenerative disc disease at only 1 level in the lumbar spine, from L3-S1, confirmed by radiographic studies (CT, MRI, x-rays, etc); AND
  3. Disc will be used for single-level reconstruction following lumbar discectomy within the L3-S1 region; AND
  4. Have no more than Grade 1 (0-25%) spondylolisthesis at the involved level; AND
  5. Minimum Oswestry Disability Index (ODI) score equal to or greater than 40; AND
  6. Radicular back/leg pain that has failed a minimum of 6 months of conservative treatment.

Artificial intervertebral lumbar disc is considered experimental, investigational and unproven for any other indications.

Rationale

Cervical Artificial Intervertebral Disc

The Prestige disc received U.S. Food and Drug Administration (FDA) marketing approval in 2007. Information on the Prestige cervical disc is available from a published report of the pivotal trial and from Medtronic’s Premarket Approval (PMA) application to the FDA. (4, 6) These documents report results from a randomized study of anterior cervical fusion (with allograft bone and plate stabilization) versus the artificial cervical disc for patients with non-axial pain and other symptoms secondary to radiculopathy or myelopathy that did not improve with a minimum 6 weeks of conservative therapy. The study was designed as a randomized, nonblinded noninferiority trial with a 10% margin. Results for 137 investigational and 148 control patients who were evaluated at 2 years post-surgery were presented to the FDA in the PMA application. These patients represented about half of the total population (276 and 265, respectively), while the peer-reviewed paper reported on about 75% of cases.

Three primary outcome variables were used in the Prestige trial: the Neck Disability Index (NDI), neurologic status, and functional spinal unit (FSU) height. The NDI is a validated multidimensional instrument that measures the effects of pain and disability on a patient’s ability to manage everyday life. (7) It is a modification of the Oswestry Low Back Pain Index, based on the response to 10 questions that focus on neck pain intensity, personal care, lifting, reading, headaches, concentration, work, driving, sleeping, and recreation. The response to each question ranges from 1 to 5, with a lower numeric score representing a better pain and disability status for that variable. A total NDI score is obtained by adding individual question scores and dividing by the maximum total of 50, if all questions are answered. Therefore, NDI scores range from 0% to 100%, with a lower percentage indicating less pain and disability. The neurologic status is a composite measure of motor function, sensory function, and deep tendon reflexes. It is used to judge if patients are within normal parameters for those categories based on physiologic measurement. Neurologic success in the Prestige trial was based on postoperative maintenance or improvement of condition as compared to preoperative status for each component. The anterior FSU height is a radiographic measure of interdiscal space. Comparison of the immediate postoperative FSU height with the 6-week postoperative value shows whether or not the disc space has decreased, which indicates that graft or device subsidence has occurred. Secondary outcome measures include the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) mental and physical component summaries, neck and arm pain status, patient satisfaction, patient global perceived effect, gait assessment, foraminal compression test, adjacent level stability and measurements, return to work, and physician’s perception.

Both data sources for the Prestige disc trial showed equivalent results. Thus, 81% of both groups showed at least a 15-point improvement for the NDI, demonstrating noninferiority to fusion but not superiority. Similarly, the FSU height measure also demonstrated evidence of noninferiority but not superiority. Neurologic status showed non-inferiority and statistical superiority for the disc compared to fusion. This contributed to the overall success composite endpoint demonstrating superiority for the disc compared to fusion. While maintained or improved neurologic status was more frequent following AIDA, it was unclear whether examiners were blinded. The majority of secondary outcome measures for the disc were deemed noninferior to ACDF, but none was statistically superior. Perioperative results and adverse events were similar in both groups, with very few serious complications.

Sixty-month follow-up of participants in this clinical trial were reported by Burkus et al. in 2010. (1) All participants were followed up in this FDA-regulated post-approval study. Outcomes at 60 months were reported on approximately half of the original randomized controlled trial (RCT) participants. The majority of the remaining patients had not yet reached that point in their follow-up, rather than being lost to follow-up. About 18% of all participants were actually lost to follow-up at 60 months. The NDI improved by 38.4 points for the Prestige disc compared to 34.1 for ACDF (p=0.022). For most other clinical outcomes, the Prestige disc was similar to ACDF, with no significant difference between groups in improvement in neck pain score (56.0 vs. 52.4) or arm pain score (52.5 vs. 47.7 – both respectively). There was a trend for greater neurologic success in the Prestige disc group (95% vs. 89%, p=0.051). Need for additional surgery was similar between the 2 procedures, and there was no significant difference in the percentage of patients requiring adjacent-level surgery (2.9% vs. 4.9% for ACDF). No implant migration was observed at up to 60 months. Bridging bone was observed in 3 of 94 patients (3.2%) with the Prestige disc.

ProDisc-C

Murrey et al. reported 2-year results from the pivotal FDA randomized noninferiority trial to determine the safety and efficacy of ProDisc-C in comparison with ACDF. (2) In this trial, 103 patients received the ProDisc-C implant and 106 were treated with fusion; participants were blinded to intervention until following surgery. Follow-up between 6 weeks and 2 years was reported to be 85% in the summary of safety and effectiveness data presented to the FDA. (3) Reasons for the loss to follow-up were not described but appear to have included 2 patients in the ProDisc-C group who had the implant removed and 5 patients in the fusion group who had undergone additional surgical procedures to modify the original implant. Non-inferiority was achieved for the FDA-defined combined endpoint of neurologic examination, neck disability index, adverse events, and device success, with 72% of ProDisc-C and 68% of fusion patients achieving success in all 4 component endpoints. Clinical outcomes at 24 months’ follow-up were reported to be similar in the ProDisc-C and fusion groups for the following components: neurologic success (91% vs. 88%), neck disability index (21.4 vs. 20.5 points), reduction in pain scores (e.g., 46 mm vs. 43 mm reduction in neck pain on a visual analogue scale [VAS]), and patient satisfaction (83 mm vs. 80 mm – all respectively).

Nabhan et al. reported 1-year clinical and radiologic results of 49 patients randomized to receive a ProDisc-C artificial disc or fusion. (4) Measurements taken at 3, 6, 12, 24, and 52 weeks showed a decrease in segmental motion at the index level in both groups over the first 12 weeks after surgery; at 52 weeks, segmental translation (xyz axis) was about 1 mm greater in the ProDisc-C group. Clinical results were similar in the two groups, with a 70% reduction in neck pain and 86% reduction in arm pain in the ProDisc-C group and a 68% reduction in neck pain and 83% reduction in arm pain in the ACDF group. As noted by the authors, longer follow-up is needed to determine the effect of this implant on cervical motion and stress at adjacent levels.

Four-year interim follow-up of participants in this clinical trial were reported by Delamarter et al. 2010. (5) All participants in the clinical trial were followed up in this FDA-regulated post-approval study. At 48 months, follow-up rates for ProDisc-C and ACDF were 63% and 46.2% respectively. It was not reported what proportion of these patients had not yet reached 48 months post-surgery or were truly lost to follow-up at that time point. Also included in this report was 24-month follow-up on 77% of 136 continued access patients who received the ProDisc-C after the clinical trial. Clinical outcomes were similar between the 3 groups, with point estimates in favor of ProDisc-C. The NDI at 48 months was 20.3 for ProDisc-C versus 21.2 for ACDF. Neurologic success was achieved in 88.9% of ProDisc-C patients in comparison with 74.4% of ACDF patients (p=0.067). There was a cumulative incidence of additional surgeries of 2.9% (3 patients) in the ProDisc-C group and 11.3% (12 patients) in the ACDF group. Two patients were converted to fusion with removal of the device; one patient had decompression with supplemental fixation without removal of the device. At 48 months, 5 ProDisc-C patients (7.7%) were found to have bridging bone.

Bryan Cervical Disc

Two- and 4-year results have been published from the IDE trial for the Bryan disc. (6, 7) The trial employed inclusion/exclusion criteria and a composite outcome identical to the ProDisc-C trial. A total of 582 patients were randomized to the Bryan disc (n=290) or ACDF (n=292). Thirty-seven patients declined surgery in the AIDA group; 80 patients declined surgery in the ACDF group. Twelve patients crossed over from AIDA to ACDF, 1 crossed over from ACDF to AIDA, and 2 patients were excluded from ACDF due to protocol violations, leaving 242 patients who underwent AIDA and 223 who underwent ACDF. In the AIDA and ACDF arms, mean age (44.4 and 44.7 years), sex (45.5% and 51.1% men) and NDI scores (51.4 and 50.2 – all respectively) were similar. All but 1 patient who underwent AIDA and 3 patients in the ACDF arm had documented neurologic abnormalities. After 2 years’ follow-up, data were available for 230 (95%) patients from the AIDA group and 194 (87%) who underwent ACDF. The overall success outcome was achieved more often after AIDA (82.6% vs. 72.7%), with a mean 4.1 point greater improvement in the NDI scores. As measured by the composite endpoint, AIDA was superior to ACDF. At 24 months, neck pain scores were lower following AIDA, while other secondary outcomes were similar. Adverse event rates were similar in the two arms—1.7% in AIDA and 3.2% in ACDF arms, requiring revision.

In 2011, 4-year follow-up from the IDE trial was reported for 181 patients (75% of 242) who received the Bryan disc and 138 patients (62% of 223) who underwent ACDF. (7) It was reported that 25% of AIDA and 38% of the ACDF patients failed to return for follow-up at 48 months, due in part to FDA and institutional review board approvals and the need for additional patient consent for the continuation study. Overall success was defined as an improvement of equal to or greater than 15 points in the NDI, neurologic improvement, no serious adverse events related to the implant or surgical implantation procedure, and no subsequent surgery or intervention that would be classified as a treatment failure. The 4-year overall success rates were significantly greater in the Bryan (85.1%) than the ACDF (72.5%) group. This finding was driven largely by differences in the NDI success (90.6% of arthroplasty and 79.0% of ACDF). Neurologic success rates were not different between the groups. Arm pain improved from a baseline of 71.2 in both groups to 16.6 for the Bryan disc and 22.4 for ACDF, the difference between groups was statistically significant. The improvement in neck pain scores was also significantly better in the Bryan disc group (from 75.4 to 20.7) compared to patients with fusion (from 74.8 to 30.6). Improvement in the SF-36 physical component score was also significantly greater in the arthroplasty group (15.8 vs. 13.1). There was no significant difference in additional surgical procedures at either the index (3.7% Bryan, 4.5% ACDF) or adjacent (4.1% Bryan, 4.1% ACDF) levels. FDA-required follow-up will continue for 10 years after the index surgery.

In the discussion of this article, the authors comment that failure of other joint arthroplasty prostheses does not typically occur until at least 5 to 10 years postoperatively and that spinal arthroplasties also need to have serial assessments to determine whether complications such as wear-related failures, device fatigue, or spinal instability have developed. They conclude that as with any motion-sparing device, “longer-term follow-up is necessary for assessment of potential problems related to bearing surface wear.”

A post hoc subgroup analysis of 199 participants with myelopathy from the Prestige ST (n=111) and Bryan (n=88) trials found similar improvement in postoperative neurologic status and gait at 24 months (Prestige ST: AIDA 90% [95% confidence interval (CI): 79% to 97%] and ACDF 81% [95% CI: 65% to 92%]; Bryan: AIDA 90% [95% CI: 76% to 97%] and ACDF 77% [95% CI: 76% to 97%]). (8) The authors noted that "although short-term results of cervical disc arthroplasty appear encouraging, studies with at least five to ten years of follow-up are required before cervical disc replacement can be viewed as a standard treatment for disc-based cervical myelopathy."

In 2010, Goffin et al. reported 4- and 6-year follow-up from Phase I and Phase II trials of the Bryan disc. (9) The total potential patient population for long-term follow-up was 98 patients (89 with 1-level and 9 with 2-level); 59 of the patients were at least 6 years postoperative. Although 4 patients from the Phase I study declined to participate in the extended follow-up study, their results were included in the safety data. Mean neck pain at 4 and 6 years postoperatively was 2.2 and 2.0, respectively. Mean arm pain at 4 and 6 years was 2.4 and 2.3, respectively. Six patients experienced events that were believed to be related to the device, including minor device migration, device removal, hoarseness, and vocal cord paralysis, while 3 of the 6 cases involved pain or neurologic symptoms. The prosthesis was removed from 1 patient at 6 years after the index surgery because of progressive spinal cord compression due to recurrent posterior osteophyte formation. About 90% of patients were classified as having excellent or good outcomes at 4 and 6 years. The success rate estimated by Kaplan-Meier analysis was 94% at 7 years following surgery.

Two-level Bryan Cervical Disc

In 2009, Cheng et al. reported 2-year follow-up from an RCT of the Bryan disc versus ACDF with autograft in 65 patients with 2-level disc disease. (10) One patient from the arthroplasty group and 2 patients from the ACDF group were lost to follow-up. Neck pain and arm pain measured by visual analog scores (VAS) tended to be better in the Bryan group (1.8 and 1.9, respectively) than the ACDF group at 12-month follow-up (2.5 and 2.4, respectively) and continued to improve at 2-year follow-up (Bryan, 1.5 and 1.4; ACDF, 2.6 and 2.7, respectively). The NDI and the SF-36 physical component scores were also significantly better in the Bryan group at both 12- and 24-month follow-up. These results support the short-term safety of the Bryan disc in 2-level disc disease; longer-term results are needed to evaluate the safety and efficacy of this device in comparison with ACDF for 2-level disc disease.

Lumbar Artificial Intervertebral Disc

Guyer et al. (13) conducted a prospective, randomized, multicenter FDA investigational device exemption study of lumbar total disc replacement with the Charité artificial disc versus lumbar fusion, to compare the safety and effectiveness of the artificial disc versus fusion. In 2009 they reported their five-year follow-up data from the original cohort of 375 patients who were randomized to receive treatment for DDD with either a Charité artificial disc or an anterior lumbar interbody fusion (ALIF) with a BAK cage and iliac crest autograft. No statistical differences were found in clinical outcomes between groups. In addition, Charité 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 range of motion (ROM) at index- and adjacent levels were not statistically different from those observed at two years postsurgery. The authors concluded that treatment with the artificial disc was not inferior to discectomy and fusion of a single lumber segment using a BAK cage.

David (14) reported a retrospective review to determine the long-term clinical results, radiographic results, and incidence of complications in 106 patient, with a mean age of 36.4 years, who received one-level lumbar total disc replacement (TDR) using a Charité. Mean follow-up time was 13.2 years (range, 10-16.8 years). Of the 106 patients, 87 (82.1%) had either an excellent or good clinical outcome. Of the 96 patients working before surgery, 86 returned to work (89.6%), including 77.8% of patients with hard labor level employment (28 of 36) returning to the same level of work. The mean ROM in flexion-extension was 10.1 degrees, in lateral bending it was 4.4 degrees, and 90.6% of implanted prostheses were still mobile. Eight patients (7.5%) required posterior instrumented fusion. There were 5 cases (4.6%) of postoperative facet arthrosis, 3 cases (2.8%) of subsidence, 3 cases (2.8%) of adjacent-level disease, and 2 cases (1.9%) of core subluxation. The author concluded that this study demonstrated the long-term safety and efficacy of the artificial disc at one level, either L4-L5 or L5-S1. Clinical outcomes and the rate of return to work were excellent overall. The rate of adjacent-level disease requiring surgical intervention was considerably lower (2.8%) compared with reports in the literature for lumbar fusion. As with any surgical procedure, proper indications play a pivotal role in clinical success.

Overall, late complications have been reported for the artificial disc (14, 15); however, these complications appear to be infrequent in the 5-10 year postoperative period, and the percentage of patients reporting good to excellent outcomes from artificial disc appears to be in the known range of success for single-level fusion. Resnick and Watters (16) report however, that artificial disc has not resulted in better outcomes than fusion. Huang et al. (17) report that long-term data indicate that, while patients may experience adjacent-level degeneration (ALD) with artificial disc, the rate is generally less than that seen with fusion. In addition, reoperation rates following Charité placement have compared to reoperation rates following fusion. David (14) reported reoperation rate of 10.3%. The US Charité IDE study (18) reported reoperation rate of 8.8% over 2 years or more of follow-up; Martin et al (19) reported 14%; Malter et al (20) reported 15%.

In 2012, Zigler et al. (21) reported the 5-year results of a prospective multicenter study in which patients were randomized to either total disc replacement (TDR) or circumferential fusion for single-level lumbar DDD, as part of an FDA-mandated postmarket approval study to evaluate long-term safety and effectiveness. Two hundred thirty-six patients were treated and followed up for 5 years; 161 TDRs and 75 fusions had been performed in these patients. The primary outcome was a 10-component success end point. Secondary outcome measures included neurological status, secondary surgery, Oswestry Disability Index (ODI), 36-Item Short Form Health Survey (SF-36), visual analog scale (VAS) assessing pain and satisfaction, radiographic data, narcotic use, activity, and recreation status. The overall follow-up rate at 5 years was 81.8%. Study success demonstrated that TDR was noninferior to fusion with a 12.5% margin (p = 0.0099). Both TDR and fusion treatment groups maintained significant improvement on the ODI at 5 years compared with baseline (p < 0.0001). Secondary surgeries at the index level were performed in 12% of fusion patients and 8% of TDR patients. Radiographically, none of the TDRs developed spontaneous fusion. The segmental range of motion following TDR remained within normal range, although it decreased by approximately 0.5° in years 3 to 5. The VAS pain scores decreased from preoperative values by 48% in both treatment groups at 5 years. Patient satisfaction remained high in both groups (77%), while the percentage of patients indicating that they would have the surgery again was higher in TDR patients (82.5%) than in fusion patients (68.0%). In conclusion, patients in both groups maintained significant improvement during the 5-year follow-up. The TDR group had significantly better improvement on some scales. TDR patients avoid the stiffness of fusion and are more satisfied than fusion patients.

Zigler et al. (22) also reported the 5-year results for radiographically demonstrated ALD changes, using the data from the FDA-mandated postmarket approval study. For the 236 patients in the study, radiographic follow-up data 5 years after treatment were available for 123 TDR patients and 43 fusion patients. To characterize ALD, radiologists at an independent facility read the radiographic films. ALD was characterized by a composite score including disc height loss, endplate sclerosis, osteophytes, and spondylolisthesis. At 5 years, changes in ALD (ΔALDs) compared with the preoperative assessment were reported; ΔALDs were observed in 9.2% of TDR patients and 28.6% of fusion patients (p = 0.004). Among the patients without adjacent-level disease preoperatively, new findings of ALD at 5 years posttreatment were apparent in only 6.7% of TDR patients and 23.8% of fusion patients (p = 0.008). Adjacent-level surgery leading to secondary surgery was reported for 1.9% of TDR patients and 4.0% of fusion patients (p = 0.6819). The TDR patients had a mean preoperative index-level range of motion ([ROM] of 7.3°) that decreased slightly (to 6.0°) at 5 years after treatment (p = 0.0198). Neither treatment group had significant changes in either ROM or translation at the superior adjacent level at 5 years posttreatment compared with baseline. The authors concluded that at 5 years after the index surgery, ProDisc-L maintained ROM and was associated with a significantly lower rate of ΔALDs than in the patients treated with circumferential fusion. In fact, the fusion patients were greater than 3 times more likely to experience ΔALDs than were the TDR patients.

Coding

Disclaimer for coding information on Medical Policies

Procedure and diagnosis codes on Medical Policy documents are included only as a general reference tool for each policy. They may not be all-inclusive.

The presence or absence of procedure, service, supply, device or diagnosis codes in a Medical Policy document has no relevance for determination of benefit coverage for members or reimbursement for providers. Only the written coverage position in a medical policy should be used for such determinations.

Benefit coverage determinations based on written Medical Policy coverage positions must include review of the member’s benefit contract or Summary Plan Description (SPD) for defined coverage vs. non-coverage, benefit exclusions, and benefit limitations such as dollar or duration caps.    

ICD-9 Codes

84.61, 84.62, 84.65, 84.66, 84.68, 722.0, 722.10, 722.11, 722.2, 722.30, 722.31, 722.32, 722.39, 722.4, 722.51, 722.52, 722.6, 722.70, 722.71, 722.72, 722.73, 722.80, 722.81, 722.83, 722.90, 722.91, 722.92, 722.93

ICD-10 Codes

M46.40, M46.42, M46.43, M46.45, M46.46, M46.47, M46.49, M50.00, M50.02, M50.03, M50.20, M50.22, M50.23, M50.30, M50.32, M50.33, M50.80, M50.82, M50.83, M50.90, M50.92, M50.93, M51.05, M51.06, M51.07, M51.25, M51.26, M51.27, M51.35, M51.36, M51.37, M51.45, M51.46, M51.47, M51.85, M51.86, M51.87, M51.9, M96.1, 0RR30JZ, 0RR50JZ, 0SR20JZ, 0SR40JZ

Procedural Codes: 0092T, 0095T, 0098T, 0163T, 0164T, 0165T, 22856, 22857, 22861, 22862, 22864, 22865
References

Cervical Artificial Intervertebral Disc (1-11) and Lumbar Artificial Intervertebral Disc (12-23)

  1. Burkus JK, Haid RW, Traynelis VC et al. Long-term clinical and radiographic outcomes of cervical disc replacement with the Prestige disc: results from a prospective randomized controlled clinical trial. J Neurosurg Spine 2010; 13(3):308-18.
  2. Murrey D, Janssen M, Delamarter R et al. Results of the prospective, randomized, controlled multicenter Food and Drug Administration investigational device exemption study of the ProDisc-C total disc replacement versus anterior discectomy and fusion for the treatment of 1-level symptomatic cervical disc disease. Spine J 2009; 9(4):275-86.
  3. ProDisc-C Summary of safety and effectiveness data. December 17, 2007. Available online at: www.fda.gov . Last accessed February 2013.
  4. Nabhan A, Ahlhelm F, Pitzen T et al. Disc replacement using Pro-Disc C versus fusion: a prospective randomised and controlled radiographic and clinical study. Eur Spine J 2007; 16(3):423-30.
  5. Delamarter RB, Murrey D, Janssen ME. Results at 24 months from the prospective, randomized multicenter investigational device exemption trial of ProDisc-C versus anterior cervical discectomy and fusion with 4-year follow-up and continued access patients. SAS J 2010; 4(4):122-8.
  6. Heller JG, Sasso RC, Papadopoulos SM et al. Comparison of BRYAN cervical disc arthroplasty with anterior cervical decompression and fusion: clinical and radiographic results of a randomized, controlled, clinical trial. Spine 2009; 34(2):101-7.
  7. Sasso RC, Anderson PA, Riew KD et al. Results of cervical arthroplasty compared with anterior discectomy and fusion: four-year clinical outcomes in a prospective, randomized controlled trial. J Bone Joint Surg Am 2011; 93(18):1684-92.
  8. Riew KD, Buchowski JM, Sasso R et al. Cervical disc arthroplasty compared with arthrodesis for the treatment of myelopathy. J Bone Joint Surg Am 2008; 90(11):2354-64.
  9. Goffin J, van Loon J, Van Calenbergh F et al. A clinical analysis of 4- and 6-year follow-up results after cervical disc replacement surgery using the Bryan Cervical Disc Prosthesis. J Neurosurg Spine 2010; 12(3):261-9.
  10. Cheng L, Nie L, Zhang L et al. Fusion versus Bryan Cervical Disc in two-level cervical disc disease: a prospective, randomised study. Int Orthop 2009; 33(5):1347-51.
  11. Artificial Intervertebral Disc: Cervical Spine. Chicago, Illinois: Blue Cross Blue Shield Association Medical Policy Reference Manual (September 2012) Surgery 7.01.108.
  12. ProDisc-L Summary of safety and effectiveness data. August 14, 2006. Available online at: www.fda.gov . Last accessed February 2013.
  13. Guyer RD, McAfee PC, Banco RJ et al. Prospective, randomized, multicenter Food and Drug Administration investigational device exemption study of lumbar total disc replacement with the CHARITE artificial disc versus lumbar fusion: five-year follow-up. Spine J 2009; 9(5):374-86.
  14. David T. Long-term results of one-level lumbar arthroplasty: minimum 10-year follow-up of the CHARITE artificial disc in 106 patients. Spine. 2007 Mar 15; 32(6):661-6.
  15. Punt IM, Visser VM, et al. Complications and reoperations of the SB Charité lumbar disc prosthesis: experience in 75 patients. Eur Spine J. 2008 Jan; 17(1):36-43.
  16. Resnick DK, Watters WC. Lumbar disc arthroplasty: a critical review. Clin Neurosurg. 2007; 54:83-7.
  17. Huang, R.C., Sandhu, S. (2004). The current status of lumbar total disc replacement. Orthopedic Clinics of North America 35, 33-42.
  18. McAfee, P.C., Geisler, F.H., Saiedy, S.S., et al (2006). Revisability of the CharitéTM artificial disc replacement. Spine 31, 1217-26.
  19. Martin, B.I., Mirza, S.K., Comstock, B.A. et al (2007). Reoperation rates following lumbar spine surgery and the influence of spinal fusion procedures. Spine 32, 382-7.
  20. Malter, A.D., McNeney, B., Loeser, J.D., Deyo, R.A. (1998). 5-year reoperation rates after different types of spinal surgery. Spine 23, 814-20.
  21. Zigler, J. Five-Year Results of the ProDisc-L Multicenter, Prospective, Randomized, Controlled Trial Comparing ProDisc-L With Circumferential Spinal Fusion for Single-Level Disabling Degenerative Disk Disease. Semin Spine Surg. 2012; 24:25-31.
  22. Zigler JE, Glenn J, Delamarter RB. Five-year adjacent-level degenerative changes in patients with single-level disease treated using lumbar total disc replacement with ProDisc-L versus circumferential fusion. J Neurosurg Spine. 2012 Dec; 17(6):504-11. Epub 2012 Oct 19.
  23. Artificial Intervertebral Disc: Lumbar Spine. Chicago, Illinois: Blue Cross Blue Shield Association Medical Policy Reference Manual (September 2012) Surgery 7.01.87.
History
August 2011 Policy reviewed: Policy statement updated to investigational, updated references and rationale. Effective date is 11/15/2011
November 2012 Policy updated with TEC Assessment and literature review through June 2012/  References added and reordered.  Policy statement unchanged.
November 2013 Combined the "Artificial Intervertebral Disc: Cervical Spine" and "Artificial Intervertebral Disc: Lumbar Spine" policies.  Title changed to "Artificial Intervertebral Disc".  Updated the policy statement to include criteria for medically necessary coverage.
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CPT codes, descriptions and material only are copyrighted by the American Medical Association. All Rights Reserved. No fee schedules, basic units, relative values or related listings are included in CPT. The AMA assumes no liability for the data contained herein. Applicable FARS/DFARS Restrictions Apply to Government Use. CPT only © American Medical Association.
Artificial Intervertebral Disc