Faculty Bibliography

BACKGROUND: Patients with cervical disc herniations resulting in radiculopathy or myelopathy from single level disease have traditionally been treated with Anterior Cervical Discectomy and Fusion (ACDF), yet Cervical Disc Arthroplasty (CDA) is a new alternative. Expert suggestion of reduced adjacent segment degeneration is a promising future result of CDA. A cost-utility analysis of these procedures with long-term follow-up has not been previously reported. METHODS: We reviewed single institution prospective data from a randomized trial comparing single-level ACDF and CDA in cervical disc disease. Both Medicare reimbursement schedules and actual hospital cost data for peri-operative care were separately reviewed and analyzed to estimate the cost of treatment of each patient. QALYs were calculated at 1 and 2 years based on NDI and SF-36 outcome scores, and incremental cost effectiveness ratio (ICER) analysis was performed to determine relative cost-effectiveness. RESULTS: Patients of both groups showed improvement in NDI and SF-36 outcome scores. Medicare reimbursement rates to the hospital were $11,747 and $10,015 for ACDF and CDA, respectively; these figures rose to $16,162 and $13,171 when including physician and anesthesiologist reimbursement. The estimated actual cost to the hospital of ACDF averaged $16,108, while CDA averaged $16,004 (p = 0.97); when including estimated physicians fees, total hospital costs came to $19,811 and $18,440, respectively. The cost/QALY analyses therefore varied widely with these discrepancies in cost values. The ICERs of ACDF vs CDA with Medicare reimbursements were $18,593 (NDI) and $19,940 (SF-36), while ICERs based on actual total hospital cost were $13,710 (NDI) and $9,140 (SF-36). CONCLUSIONS: We confirm the efficacy of ACDF and CDA in the treatment of cervical disc disease, as our results suggest similar clinical outcomes at one and two year follow-up. The ICER suggests that the non-significant added benefit via ACDF comes at a reasonable cost, whether we use actual hospital costs or Medicare reimbursement values, though the actual ICER values vary widely depending upon the CUA modality used. Long term follow-up may illustrate a different profile for CDA due to reduced cost and greater long-term utility scores. It is crucial to note that financial modeling plays an important role in how economic treatment dominance is portrayed.

BACKGROUND: Cervical laminoplasty (CLP) and posterior cervical laminectomy and fusion (CLF) are well-established surgical procedures used in the treatment of cervical spondylotic myelopathy (CSM). In situations of clinical equipoise, an influential factor in procedural decision making could be the economic effect of the chosen procedure. The object of this study is to compare and analyze the total hospital costs and charges pertaining to patients undergoing CLP or CLF for the treatment of CSM. METHODS: We performed a retrospective review of 81 consecutive patients from a single institution; 55 patients were treated with CLP and 26 with CLF. CLP was performed via the double-door allograft technique that does not require implants, whereas laminectomy fusion procedures included metallic instrumentation. We analyzed 10,682 individual costs (HC) and charges (HCh) for all patients, as obtained from hospital accounting data. The Current Procedural Terminology codes were used to estimate the physicians' fees as such fees are not accounted for via hospital billing records. Total cost (TC) therefore equaled the sum of the hospital cost and the estimated physicians' fees. RESULTS: The mean length of stay was 3.7 days for CLP and 5.9 days for CLF (P < .01). There were no significant differences between the groups with respect to age, gender, previous surgical history, and medical insurance. The TC mean was $17,734 for CLP and $37,413 for CLF (P < .01). Mean HCh for CLP was 42% of that for CLF, and therefore the mean charge for CLF was 238% of that for CLP (P < .01). Mean HC was $15,426 for CLP and $32,125 for CLF (P < .01); the main contributor was implant cost (mean $2582). CONCLUSIONS: Our study demonstrates that, in clinically similar populations, CLP results in reduced length of stay, TC, and hospital charges. In CSM cases requiring posterior decompression, we demonstrate CLP to be a less costly procedure. However, in the presence of neck pain, kyphotic deformity, or gross instability, this procedure may not be sufficient and posterior CLF may be required.

BACKGROUND CONTEXT: Conjoined nerve roots are a relatively uncommon finding but are frequently undiagnosed on preoperative imaging studies. The presence of a conjoined root anomaly represents a significant potential for neurologic injury when nerve root mobilization is necessary during spinal procedures. PURPOSE: This comprehensive review of conjoined lumbar nerve roots encompasses preoperative diagnosis by physical examination and radiographic imaging studies, as well as the intraoperative management of conjoined nerve roots. STUDY DESIGN: Systematic review of existing literature. RESULTS: Findings have been described on standard magnetic resonance imaging (MRI) and computed tomography imaging to increase preoperative diagnosis rates. The literature lacks concrete recommendations regarding intraoperative techniques for conjoined root identification and management. CONCLUSIONS: Preoperative recognition and diagnosis of this anomaly has proven to be the best way to improve the chances of a successful procedure and avoid inadvertently damaging the nerve roots intraoperatively. Several radiographic signs of conjoined lumbar nerve roots have been described using standard MRI techniques including coronal T1- and T2-weighted sequences. Intraoperative management of conjoined nerve roots has not changed significantly since they were first identified, although diagnostic accuracy has improved with advanced MRI techniques.

Spine Tango is currently the only international spine registry in existence. It was developed under the auspices of Eurospine, the Spine Society of Europe, and is hosted at the University of Bern, Switzerland. The HJD Spine Center successfully tested Spine Tango during a 3-month pilot study and has since expanded documentation activities to more surgeons. Workflow integration and dedicated research staff are key factors for such an endeavor. Participation enables benchmarking against national and international peers and outcome research and quality assurance of surgical and non-surgical treatments.

STUDY DESIGN: Retrospective chart review. PURPOSE: To evaluate the incidence of potential total disc replacement (TDR) candidates among cervical and lumbar fusion patient populations using strict Food and Drug Administration (FDA) criteria and with relative exclusion criteria removed. OVERVIEW OF LITERATURE: Recent studies suggest that the potential percentage of patients that are candidates for TDR ranges from 0-5% in lumbar fusions and 43% in cervical fusions. METHODS: We performed a retrospective chart review of 280 consecutive patients who had lumbar (n = 174) and cervical (n = 106) fusion or TDR performed by one of four independent adult orthopaedic spine surgeons. Charts were screened for investigational device exemption (IDE) inclusion/exclusion criteria and later reanalyzed excluding relative exclusion criteria, such as history of chronic medical illness, twolevel disease (cervical cases), and history of prior fusion surgery in the anatomic region. RESULTS: Of the 174 lumbar surgeries, 10 were TDR with Prodisc-L and 164 were lumbar fusions. The most common TDR exclusion criteria were lytic spondylolisthesis or spinal stenosis (47.7% of patients) and more than 2 level degenerative disc disease (37.9%). 14.9% had no IDE exclusion criteria and would be considered candidates for TDR. After excluding the relative lumbar exclusion criteria, this percentage increased to 25.8%. Of the 106 cervical cases, 3 had a TDR with Prodisc-C and 103 had a cervical fusion. Twenty eight percent had no IDE exclusion criteria and would be considered candidates for cervical TDR. CONCLUSIONS: A larger percentage of cervical fusion candidates are potential candidates for TDR (28%) than lumbar fusion candidates (14.9%) based on the strict IDE criteria

BACKGROUND: There is uncertainty in the literature over the relative effectiveness of lumbar epidural interlaminar (IL) steroid injection versus transforaminal (TF) steroid injection for lumbar radiculopathy. Most studies to date have been retrospective, or technically focused. OBJECTIVE: To complete a randomized, blinded, prospective outcome study of the short-term benefit for IL versus TF epidural steroids for the treatment of subacute lumbar radicular pain. STUDY DESIGN: Prospective, randomized, blinded, subacute efficacy trial. SETTING: Tertiary care pain management center, major metropolitan city, United States METHODS: After institutional review board approval, 42 age-matched patients with similar lower back pain and unilateral radicular symptoms were enrolled and randomized in a patient and evaluating physician blinded trial to IL or TF epidural steroids from 2007 through 2009. Prior to intervention and 10-16 days after injection, each participant was evaluated by questionnaire and physical exam by an independent physician. All injections were performed by the same physician. Thirty-eight participants completed the study, 18 in the IL group and 20 in the TF group. Four participants required a repeat injection, and 2 participants crossed over to the alternative injection type (IL to TF). RESULTS: Overall, physical exam, diagnostic testing, disability, activity, depression measures, and opioid pill use were similar between the 2 groups, both pre-injection baseline and post-injection improvement. In primary outcomes, the post-injection follow-up Numeric Rating Scale (NRS) was more greatly reduced in the TF group. The NRS decreased from 7.0 +/- 1.9 to 3.9 +/- 3.1 (mean values +/- standard deviation) in the IL group and 6.4 +/- 2.1 to 1.7 +/- 1.4 in the TF group. The Oswestry Disability Index was reduced from 37.5 +/- 12.6 to 19.0 +/- 16.7 in the IL group and 38.3 +/- 6.4 to 21.6 +/- 16.8 in the TF group. In secondary outcomes, the depression scale was reduced from 4.39 +/- 3.22 to 2.28 +/- 3.20 in the IL group and 4.10 +/- 1.94 to 1.65 +/- 1.63 in the TF group. Walking tolerance was increased from 8.1 +/- 4.6 blocks to 10.6 +/- 4.4 in the IL group and 8.9 +/- 5.3 blocks to 11.8 +/- 4.2 in the TF group. LIMITATIONS: The study did not examine long-term outcomes. A single experienced interventionalist performed all injections. CONCLUSION: Results suggest that patients may experience greater subjective relief, at least initially, from TF epidural steroid injections over IL. However, more objective, and likely subacute, therapeutic effects are similar

This article is the second article in a two-part review on lumbar facet joint pathology. In this review, we discuss the current concepts and controversies regarding the proper diagnosis and management of patients presenting with presumed facet-mediated lower back pain. All efforts were made to include the most relevant literature from the fields of radiology, orthopaedics, physiatry, and pain management. Our focus in this article is on presenting the evidence supporting or refuting the most commonly employed injection-based therapies for facet-mediated lower back pain

We present a two-part review article on the current state of knowledge of lumbar facet joint pathology. This first article discusses the functional anatomy, biomechanics, and radiological grading systems currently in use in clinical practice and academic medicine. Facet joint degeneration is presented within the larger context of degenerative disc disease to enable the reader to better understand the anatomical changes underlying facet-mediated lower back pain. Other less-common, but equally important etiologies of lumbar facet joint degeneration are reviewed. The existing grading systems are discussed with specific reference to the reliability of CT and MR imaging in the diagnosis of lumbar facet osteoarthritis. It is hoped that this discussion will stimulate debate on how best to improve the diagnostic reliability of these tests so as to improve both operative and non-operative treatment outcomes

BACKGROUND CONTEXT: There is increasing research describing the use of a nerve root sedimentation sign to diagnose lumbar spinal stenosis LSS). In patients with LSS, the lack of sedimentation of the nerve roots (positive sedimentation sign) to the dorsal part of the dural sac is the characteristic feature of this new radiological parameter. PURPOSE: To demonstrate how the nerve root sedimentation sign compares to other, more traditional, radiological parameters in patients who have been operated on for LSS. STUDY DESIGN/SETTING: A retrospective study of the preoperative axial T2 weighted MR images of patients at a single institution who presented with LSS and received spinal decompression surgery. PATIENT SAMPLE: 77 patients (33 male and 44 female, mean age565 years) who presented from 2006 to 2010 with LSS. OUTCOME MEASURES: Positive and negative sedimentation signs distinguish the absence or presence of nerve root sedimentation to the dorsal part of the dural sac, respectively. METHODS: In total, 143 vertebral levels from L1 to L5 were measured on MRIs for the following parameters: sedimentation sign, cross-sectional area of the dural sac, thickness of the ligamentum flavum, anterior/posterior diameter of the dural sac, and the Fujiwara grade of facet hypertrophy. Radiological measurements were made using Surgimap 1.1.2.169 software. Statistical analyses were performed using the statistical software SPSS 17.0. Significance was demonstrated using unpaired t-tests and Chi-Squared tests. Patients with previous spine surgeries were excluded from the study. RESULTS: A positive sedimentation sign was determined in 125 operated levels (87.43%), while 18 levels had no sign. The most common operated levels were L3-4 and L4-5. There was a significant difference in CSA and A/P diameter between those levels with and without a sedimentation sign. The mean CSA was 160.17 mm2 (sd567.14) for the negative sign group whereas the mean CSA was 84.43 mm2 (sd539.21) for the sedimentation sign group (p<.001). Similarly, the mean A/P diameter was 12.89 mm (sd53.61) for the negative sign group whereas the mean A/P diameter was 8.95 mm (sd52.45) for the sedimentation sign group (p<.001). There was no significant difference between groups in terms of ligamentum flavum thickness. In 77.8% of levels with CSAO100mm2 there was no sedimentation sign, whereas in 72.0% of levels with CSA<100mm2 there was a sedimentation sign (p<.001).We found that 60% of levels with Fujiwara gradeA facet hypertrophy do not have a sedimentation sign whereas 81.8% of levels with grade B, 96.7% of levels with grade C, and 100.0% of levels with grade D do have a sedimentation sign (p<.001). CONCLUSIONS: The interpretation and radiographic grade of severity of lumbar spinal stenosis on MRIs is quite subjective. Most reports quantify stenosis as 'mild, moderate or severe', without any standard method of interpretation or calibration. The sedimentation sign is a new measurement tool that enables physicians to objectively assess and quantify spinal stenosis. In addition, the sign is most often present in patients who have clinically significant lumbar stenosis who require surgery