Mazda K. Turel, Mena G. Kerolus, Owoicho Adogwa and Vincent C. Traynelis
The aim of this paper was to comprehensively review each of the Food and Drug Administration (FDA)–approved labels of 7 total cervical disc replacements, assess the exact methodology in which the trial was conducted, and provide a broad comparison of these devices to allow each surgeon to determine which disc best suits his or her specific treatment goals based on the specific labels and not the studies published.
The FDA-approved labels for each of the 7 artificial discs were obtained from the official FDA website. These labels were meticulously compared with regard to the statistical analysis performed, the safety and efficacy data, and the randomized controlled trial that each artificial disc was involved in to obtain the FDA approval for the product or device. Both single-level and 2-level approvals were examined, and primary and secondary end points were assessed.
In the single-level group, 4 of the 7 artificial discs—Prestige LP, Prestige ST, Bryan, and Secure-C—showed superiority in overall success. Prestige ST showed superiority in 3 of 4 outcome measures (neurological success, revision surgery, and overall success), while the other aforementioned discs showed superiority in 2 or fewer measures (Prestige LP, neurological and overall success; Bryan, Neck Disability Index [NDI] and overall success; Secure-C, revision surgery and overall success; Pro-Disc C, revision surgery). The PCM and Mobi-C discs demonstrated noninferiority across all outcome measures. In the 2-level group, Prestige LP and Mobi-C demonstrated superiority in 3 outcome measures (NDI, secondary surgery, and overall success) but not neurological success.
This paper provides a comprehensive analysis of 7 currently approved and distributed artificial discs in the United States. It compares specific outcome measures of these devices against those following the standard of care, which is anterior cervical discectomy and fusion. This information will provide surgeons the opportunity to easily answer patients' questions and remain knowledgeable when discussing devices with manufacturers.
Owoicho Adogwa, Aladine A. Elsamadicy, Jing L. Han, Joseph Cheng, Isaac Karikari and Carlos A. Bagley
With the recent passage of the Patient Protection and Affordable Care Act, there has been a dramatic shift toward critical analyses of quality and longitudinal assessment of subjective and objective outcomes after lumbar spine surgery. Accordingly, the emergence and routine use of real-world institutional registries have been vital to the longitudinal assessment of quality. However, prospectively obtaining longitudinal outcomes for patients at 24 months after spine surgery remains a challenge. The aim of this study was to assess if 12-month measures of treatment effectiveness accurately predict long-term outcomes (24 months).
A nationwide, multiinstitutional, prospective spine outcomes registry was used for this study. Enrollment criteria included available demographic, surgical, and clinical outcomes data. All patients had prospectively collected outcomes measures and a minimum 2-year follow-up. Patient-reported outcomes instruments (Oswestry Disability Index [ODI], SF-36, and visual analog scale [VAS]-back pain/leg pain) were completed before surgery and then at 3, 6, 12, and 24 months after surgery. The Health Transition Index of the SF-36 was used to determine the 1- and 2-year minimum clinically important difference (MCID), and logistic regression modeling was performed to determine if achieving MCID at 1 year adequately predicted improvement and achievement of MCID at 24 months.
The study group included 969 patients: 300 patients underwent anterior lumbar interbody fusion (ALIF), 606 patients underwent transforaminal lumbar interbody fusion (TLIF), and 63 patients underwent lateral interbody fusion (LLIF). There was a significant correlation between the 12- and 24-month ODI (r = 0.82; p < 0.0001), SF-36 Physical Component Summary score (r = 0.89; p < 0.0001), VAS-back pain (r = 0.90; p < 0.0001), and VAS-leg pain (r = 0.85; p < 0.0001). For the ALIF cohort, patients achieving MCID thresholds for ODI at 12 months were 13-fold (p < 0.0001) more likely to achieve MCID at 24 months. Similarly, for the TLIF and LLIF cohorts, patients achieving MCID thresholds for ODI at 12 months were 13-fold and 14-fold (p < 0.0001) more likely to achieve MCID at 24 months. Outcome measures obtained at 12 months postoperatively are highly predictive of 24-month outcomes, independent of the surgical procedure.
In a multiinstitutional prospective study, patient-centered measures of surgical effectiveness obtained at 12 months adequately predict long-term (24-month) outcomes after lumbar spine surgery. Patients achieving MCID at 1 year were more likely to report meaningful and durable improvement at 24 months, suggesting that the 12-month time point is sufficient to identify effective versus ineffective patient care.
Daniel B. Loriaux, Owoicho Adogwa and Oren N. Gottfried
A true adult spinal lipoma is an exceedingly rare cause of lumbar compression neuropathy. Only 5 cases of true extradural intraforaminal lipomas have been documented in the medical literature. The diagnostic criteria and treatment guidelines for this specific lipoma have yet to be established. This report features 3 histologically confirmed cases of extradural intraforaminal spinal lipomas that recently presented to the authors’ practice. In addition, the literature was surveyed to include the 5 previously reported cases of true adult extradural intraforaminal spinal lipomas. The consistency in presentation, response to surgical intervention, and postoperative recovery in these 8 cases supports surgical intervention at the time of diagnosis. The authors’ findings support elevated clinical suspicion, efficient diagnosis based on MRI, and early surgical intervention for this rare pathological entity. All cases presented in this report were symptomatic and occurred in the absence of other significant pathologies such as general spinal epidural lipomatosis, intradural lesions, tethering, or severe degenerative stenosis or herniated discs. The clinical, neuroradiological, and histological findings characteristic of a true adult extradural intraforaminal lipoma are emphasized to differentiate this lesion from the more common etiologies for lumbar compression neuropathy. Heightened awareness and clinical suspicion for the focal, foraminal spinal lipoma as a cause of radiculopathy symptoms will enable more efficient diagnosis and treatment.
Joel R. Martin, Owoicho Adogwa, Christopher R. Brown, Maragatha Kuchibhatla, Carlos A. Bagley, Shivanand P. Lad and Oren N. Gottfried
Recent studies have reported that the local delivery of vancomycin powder is associated with a decrease in spinal surgical site infection. This retrospective cohort study compares posterior cervical fusion cases before and after the routine application of spinal vancomycin powder to evaluate the ability of local vancomycin powder to prevent deep wound infection after posterior cervical spinal fusion.
Posterior cervical fusion spinal surgeries performed at a single institution were reviewed from January 2011 to July 2013. Each cohort's baseline characteristics, operative data, and rates of wound infection were compared. Associations between infection and vancomycin powder, with and without propensity score adjustment for risk factors, were determined using logistic regression.
A total of 289 patients (174 untreated and 115 treated with vancomycin powder) were included in the study. The cohorts were similar in terms of baseline and operative variables. No significant change in deep wound infection rate was seen between the control group (6.9%) and intervention group (5.2%, p = 0.563). Logistic regression, with and without propensity score adjustment, demonstrated that the use of vancomycin powder did not impact the development of surgical site infection (OR 0.743 [95% CI 0.270–2.04], p = 0.564) and (OR 0.583 [95% CI 0.198–1.718], p = 0.328), respectively.
Within the context of an ongoing debate on the effectiveness of locally administered vancomycin powder, the authors found no significant difference in the incidence of deep wound infection rates after posterior cervical fusion surgery with routine use of locally applied vancomycin powder. Future prospective randomized series are needed to corroborate these results.
Owoicho Adogwa, Terence Verla, Paul Thompson, Anirudh Penumaka, Katherine Kudyba, Kwame Johnson, Erin Fulchiero, Timothy Miller Jr., Kimberly B. Hoang, Joseph Cheng and Carlos A. Bagley
Depression and persistent low-back pain (LBP) are common and disabling problems in elderly patients (> 65 years old). Affective disorders, such as depression and anxiety, are also common in elderly patients, with a prevalence ranging from 4% to 16%. Depressive symptoms are consistently associated with functional disability. To date, few studies have assessed the predictive value of baseline depression on outcomes in the setting of revision spine surgery in elderly patients. Therefore, in this study, the authors assessed the predictive value of preoperative depression on 2-year postoperative outcomes.
A total of 69 patients undergoing revision neural decompression and instrumented fusion for adjacent-segment disease (ASD, n = 28), pseudarthrosis (n = 17), or same-level recurrent stenosis (n = 24) were included in this study. Preoperative Zung Self-Rating Depression Scale (ZDS) scores were assessed for all patients. Preoperative and 2-year postoperative visual analog scale (VAS) scores for back pain (VAS-BP) and leg pain (VAS-LP) and the Oswestry Disability Index (ODI) were also assessed. The association between preoperative ZDS score and 2-year improvement in disability was assessed via multivariate regression analysis.
Compared with preoperative status, 2-year postoperative VAS-BP was significantly improved after surgery for ASD (9 ± 2 vs 4.01 ± 2.56, respectively; p = 0.001), as were pseudarthrosis (7.41 ± 1 vs 5.0 ± 3.08, respectively; p = 0.02) and same-level recurrent stenosis (7 ± 2.00 vs 5.00 ± 2.34, respectively; p = 0.003). Two-year ODI was also significantly improved after surgery for ASD (29 ± 9 vs 23.10 ± 10.18, respectively; p = 0.001), as were pseudarthrosis (28.47 ± 5.85 vs 24.41 ± 7.75, respectively; p = 0.001) and same-level recurrent stenosis (30.83 ± 5.28 vs 26.29 ± 4.10, respectively; p = 0.003). Independent of other factors—age, body mass index, symptom duration, smoking, comorbidities, severity of preoperative pain, and disability—increasing preoperative ZDS score was significantly associated with lower 2-year improvement in disability (ODI) after revision surgery in elderly patients with symptomatic ASD, pseudarthrosis, or recurrent stenosis.
The extent of preoperative depression is an independent predictor of less functional improvement following revision lumbar surgery in elderly patients with symptomatic ASD, pseudarthrosis, or recurrent stenosis. Timely diagnosis and treatment of depression and somatic anxiety in this cohort of patients may contribute to improvement in postoperative functional status.