Cost-effectiveness of single-level anterior cervical discectomy and fusion for cervical spondylosis

Usefulness of polyetheretherketone (PEEK) cage with plate augmentation for anterior arthrodesis in traumatic cervical spine injury

BACKGROUND CONTEXT

Even though many clinical reports about cages have been documented in patients with degenerative disorders, reports were scarce for traumatic injury cases, and those cases using metal cages were restricted to only one-level injury.

PURPOSE

To evaluate the usefulness of polyetheretherketone (PEEK) cage and plate construction in anterior interbody fusions (AIF) for traumatic cervical spine injuries by analyzing radiographic changes and clinical outcomes.

STUDY DESIGN/SETTING

Retrospective study.

PATIENT SAMPLE

Fifty-eight patients (91 levels) underwent cage and plate construction for treatment of traumatic cervical spine injury.

OUTCOME MEASURES

The fusion rate, fusion time, changes of Cobb angle, subsidence rate, and adjacent level changes were assessed as a radiographic outcome. Clinical analysis includes the recovery rate on the American Spinal Injury Association (ASIA) impairment scale and the presence of the complications.

METHODS

We evaluated 58 patients (91 levels) who underwent surgery and had at least 24 months in follow-up study. Radiographic evaluation included the assessment of interbody fusion rate, fusion time, changes of Cobb angle, subsidence rate, and adjacent level changes. Clinical assessment was done by analyzing recovery state of ASIA impairment scale from preoperative period to the last follow-up and by evaluating complications.

RESULTS

Fifty-four cases showed bony fusion within 3 months after the surgery. The mean Cobb angle between the vertebral bodies was 2.54 degrees before operation, 9.13 degrees after operation, and 8.39 degrees at the latest follow-up. The mean intervertebral disc height was increased by 3.01 mm after the operation, but the mean height was 2.17 mm shorter at the last follow-up than after postoperation. In terms of clinical results, five Grade A cases and one Grade B case as assessed by the ASIA impairment scale were unchanged until the last follow-up. Twenty-three cases of Grade C, 16 cases of Grade D, and 13 cases of Grade E improved to seven cases, 26 cases, and 19 cases, respectively. Three cases went through additional surgery, two posterior fusions for delayed union and posterior instability and one AIF for adjacent level disease.

CONCLUSION

The PEEK cage and additional plate fixation is a surgical procedure that decreases donor site morbidity, obtains high fusion rate with rigid fixation, and provides satisfactory clinical outcome for traumatic cervical spine injuries, regardless of the numbers of the involved levels.

Bone graft substitutes in anterior cervical discectomy and fusion

Anterior cervical discectomy with fusion is a common surgical procedure for patients suffering pain and/or neurological deficits and unresponsive to conservative management. For decades, autologous bone grafted from the iliac crest has been used as a substrate for cervical arthrodesis. However patient dissatisfaction with donor site morbidity has led to the search for alternative techniques. We present a literature review examining the progress of available grafting options as assessed in human clinical trials, considering allograft-based, synthetic, factor- and cell-based technologies.

Prospective nonrandomized comparison of an allograft with bone morphogenic protein versus an iliac-crest autograft in anterior cervical discectomy and fusion

BACKGROUND CONTEXT

Anterior cervical discectomy and fusion (ACDF) using autogenous iliac bone graft may lead to donor-site morbidity. This has led some surgeons to use alternatives to iliac bone graft, but often the alternatives have greater rates of nonunion and delayed union. Bone morphogenic protein (BMP) studies have found high arthrodesis rates in lumbar fusions.

PURPOSE

The objective of this pilot study was to compare the success of BMP combined with bone allograft with iliac bone autograft in ACDF patients.

STUDY DESIGN/SETTING

The institutional review board approved a prospective but nonrandomized study of 66 consecutive patients who had primary one- to three-level ACDF with either iliac-crest bone autograft or BMP allograft (0.9 mg BMP per level) followed prospectively over a 2- to 3-year period.

PATIENT SAMPLE

Consecutive patients who had primary one- to three-level ACDF with either iliac-crest bone autograft (n=36) or BMP-allograft (n=30). Patients in both iliac bone graft and BMP-allograft groups had comparable preoperative pain and disability.

OUTCOME MEASURES

Visual analog scale pain, pain drawing, Oswestry index, pain medication use, opinion of treatment success, and neurological recovery.

RESULTS

Given the nonrandomized nature of the study, the study groups were not matched. Within this limitation, both groups of patients had similar improvement in all outcome scales (visual analog scale pain, pain drawing, Oswestry index, pain medication use, and opinion of treatment success) and neurological recovery over the 2- to 3-year follow-up period. Patients in the iliac bone graft group had two pseudarthroses and two complications of the iliac-crest donor site. In the BMP-allograft group, one patient had a pseudarthrosis, but 50% had neck swelling presenting as dysphagia, which was substantially more common than the 14% present in the iliac bone graft group. Patients in the BMP-allograft group had slightly shorter surgery time, but implant and hospitalization costs were higher.

CONCLUSIONS

ACDF performed with BMP (0.9 mg BMP per level) allograft is as effective as iliac bone graft in terms of patient outcomes and fusion rates. Safety concerns related to neck swelling and higher initial costs were associated with patients in the bone morphogenic protein group.

ISSLS prize winner: cost-effectiveness of two forms of circumferential lumbar fusion: a prospective randomized controlled trial

STUDY DESIGN

Economic evaluation alongside a prospective, randomized controlled trial from a secondary care National Health Service (NHS) perspective.

OBJECTIVE

To determine the cost-effectiveness of titanium cages (TC) compared with femoral ring allografts (FRA) in circumferential lumbar spinal fusion.

SUMMARY OF BACKGROUND DATA

A randomized controlled trial has shown the use of TC to be clinically inferior to the established practice of using FRA in circumferential lumbar fusion. Health economic evaluation is urgently needed to justify the continued use of TC, given that this treatment is less effective and, all things being equal, is assumed more costly than FRA.

METHODS

Eighty-three patients were randomly allocated to receive either the TC or FRA as part of a circumferential lumbar fusion between 1998 and 2002. NHS costs related to the surgery and revision surgery needed during the trial period were monitored and adjusted to the base year (2005-2006 Pounds Sterling). The Short Form-6D (SF-6D) was administered before surgery and at 6, 12 and 24 months in order to elicit patient utility and subsequently Quality-Adjusted Life Years (QALYs) for the trial period. Return to paid employment was also monitored. Bootstrapped mean differences in discounted costs and benefits were generated in order to explore cost-effectiveness.

RESULTS

A significant cost difference of pound 1950 (95% CI, pound 849 to pound 3145) in favor of FRA was found. Mean QALYs per patient over the 24-month trial period were 0.0522 (SD, 0.0326) in the TC group and 0.1914 (SD, 0.0398) in the FRA group, producing a significant difference of -0.1392 (95% CI, -0.2349 to -0.0436). With regard to employment, incremental productivity costs were estimated at pound 185,171 in favor of FRA.

CONCLUSION

From an NHS perspective, the trial data show that TC is not cost-effective in circumferential lumbar fusion. The use of FRA was both cheaper and generated greater QALY gains. In addition, FRA patients reported a greater return to work rate.

An economic model of one-level lumbar arthroplasty versus fusion

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.

SF-36 PCS benefit-cost ratio of lumbar fusion comparison to other surgical interventions: a thought experiment

STUDY DESIGN

A retrospective review of prospectively collected data.

OBJECTIVES

To review systematically the SF-36 PCS outcomes of a large data set, including several randomized clinical trials for lumbar spine fusion at 1 and 2 years after surgery. We also present for comparison a review of typical changes in SF-36 PCS in other surgical interventions (total knee replacement, total hip replacement, and coronary artery bypass surgery) to define the average reimbursement costs per PCS improvement with each of these interventions.

SUMMARY AND BACKGROUND DATA

Data from 11 prospective multicenter studies (9 Food and Drug Administration Investigational Device Exemption, Randomized Prospective Clinical Trials, class 1 data) accounted for the lumbar spine fusion group (n = 1826). Data for total knee replacement, total hip replacement, and coronary artery bypass surgery were obtained from a comprehensive review of the literature.

METHODS

Comparisons of SF-36 PCS improvements were made at defined postoperative time points and with published study findings of other medical conditions. Reimbursement estimates (not including estimated physician and rehabilitation fees) for each surgical intervention were based on Centers for Medicare and Medicaid Services Medicare Provider Analysis and Review and All Payer Data (2002). Cost estimates were calculated for a minimal clinical important improvement (reimbursement dollars/mean PCS change *5.42 point PCS improvement).

RESULTS

SF-36 PCS significantly improved at both 1 and 2 years following lumbar spine fusion surgery (P < 0.0001), and was comparable to the control surgical outcomes. With the use of data from Centers for Medicare and Medicaid Services Medicare Provider Analysis and Review and All Payer Data, hospital reimbursement averaged $15.2-18.2K for lumbar spine fusion, $9.8-11.3K for total knee replacement, $9.6-11.3K for total hip replacement, and $9.8-11.3K for coronary artery bypass surgery. Calculations of reimbursement dollars to elicit minimum clinically important change in PCS of 5.42 points following surgery ranged from $6.1 to $7.3K for lumbar spine fusion, $5.7 to $6.6K for total knee arthroplasty, $3.9 to $4.5K for total hip replacement, and $18.2 to $22.5K for coronary artery bypass surgery.

CONCLUSION

While the exact numbers may vary for each treatment based on the population studied and the cost estimates used, lumbar fusion cost per benefit achieved was very comparable to other well-accepted medical interventions (total hip replacement, total knee replacement, and coronary artery bypass surgery).

Cost-utility analysis of routine neurosurgical spinal surgery

OBJECT

Cost-utility analysis is currently the preferred method with which to compare the cost-effectiveness of various interventions. The authors conducted a study to establish the cost-utility results of routine neurosurgery-based spinal interventions by examining patient-derived values.

METHODS

Two hundred seventy patients undergoing surgery for cervical or lumbar radicular pain filled in the 15-dimensional health-related quality of life (HRQOL) questionnaire before and 3 months after surgery. Quality-adjusted life years (QALYs) were calculated using the utility data and the expected remaining life years of the patients. The mean HRQOL score (scale, 0-1) increased after cervical surgery (169 patients, mean age 52 years, 40% women) from 0.81 +/- 0.11 preoperatively, to 0.85 +/- 0.11 at 3 months, and after lumbar surgery (101 patients, mean age 54 years, 59% women) from 0.79 +/- 0.10 preoperatively, to 0.85 +/- 0.12 at 3 months (p < 0.001). Of the 15 dimensions of health, improvement in the following was documented in both groups: sleeping, usual activities, discomfort and symptoms, depression, distress, vitality, and sexual activity (p < 0.05). The cost per QALY gained was Euro 2774 and 1738 for cervical and lumbar operations, respectively. In cases in which surgery was delayed the cost per QALY was doubled.

CONCLUSIONS

Spinal surgery led to a statistically significant and clinically important improvement in HRQOL. The cost per QALY gained was reasonable, less than half of that observed, for example, for hip replacement surgery or angioplasty treatment of coronary artery disease; however, a prolonged delay in surgical intervention led to an approximate doubling of the cost per QALY gained by the treatment.

Lumbar disc disorders and low-back pain: socioeconomic factors and consequences

Socioeconomic factors are important risk factors for lumbar pain and disability. The total costs of low-back pain in the United States exceed $100 billion per year. Two-thirds of these costs are indirect, due to lost wages and reduced productivity. Each year, the fewer than 5% of the patients who have an episode of low-back pain account for 75% of the total costs. Because indirect costs rely heavily on changes in work status, total costs are difficult to calculate for many women and students as well as elderly and disabled patients. These methodologic challenges notwithstanding, the toll of lumbar disc disorders is enormous, underscoring the critical importance of identifying strategies to prevent these disorders and their consequences.