Journal of Neurosurgery: Spine
Daniel Lubelski, Matthew D. Alvin, Sergiy Nesterenko, Swetha J. Sundar, Nicolas R. Thompson, Edward C. Benzel and Thomas E. Mroz
Studies comparing surgical treatments for cervical spondylotic myelopathy (CSM) are heterogeneous, using a variety of different quality of life (QOL) outcomes and myelopathy-specific measures. This study sought to evaluate the relationship of these measures to each other, and to better understand their use in evaluating patients with CSM.
A retrospective study was performed in all patients with CSM who underwent either ventral or dorsal cervical spine surgery at a single tertiary-care institution between January 2008 and July 2013. Severity of myelopathy was assessed pre- and postoperatively using both the Nurick scale and the modified Japanese Orthopaedic Association (mJOA) classification of disability. Prospectively collected QOL outcomes data included Pain Disability Questionnaire (PDQ), Patient Health Questionnaire–9 (PHQ-9), and EQ-5D. Spearman rank correlations were calculated to assess the construct convergent validity for each pair of health status measures (HSMs). To assess each HSM’s ability to discriminate favorable EQ-5D index, we performed receiver operating characteristic (ROC) curve analysis and assessed the area under the curve (AUC).
A total of 119 patients were included. The PDQ total score had the highest correlation with EQ-5D index (Spearman’s rho = −0.82). Neither of the myelopathy scales (mJOA or Nurick) had strong correlations between themselves (0.41) or with the other QOL measures (absolute value range 0.13–0.49). In contrast, the QOL measures correlated relatively well with each other (absolute value range 0.68–0.97). For predicting favorable EQ-5D outcomes, PDQ total score had an AUC of 0.909. The AUCs were significantly greater for the QOL measures in comparison with the myelopathy measures (AUCs were 0.677 and 0.607 for mJOA and Nurick scale scores, respectively).
The authors found that all included measures of QOL and CSM-specific (mJOA or Nurick scale) measures were valid and responsive. The PDQ was the most predictive of positive QOL after surgery (as measured by the EQ-5D index) for patients with CSM. The substantially lower correlation between myelopathy and QOL outcomes, compared with the various QOL measures themselves, suggests that these questionnaires are measuring different aspects of the patient experience. Solely assessing the myelopathy or disease-specific signs and symptoms is likely insufficient to fully understand and appreciate clinical outcome in its totality. These questionnaire types should be used together to best evaluate patients pre- and postoperatively.
Benjamin D. Kuhns, Daniel Lubelski, Matthew D. Alvin, Jason S. Taub, Matthew J. McGirt, Edward C. Benzel and Thomas E. Mroz
Infections following spine surgery negatively affect patient quality of life (QOL) and impose a significant financial burden on the health care system. Postoperative wound infections occur at higher rates following dorsal cervical procedures than ventral procedures. Quantifying the health outcomes and costs associated with infections following dorsal cervical procedures may help to guide treatment strategies to minimize the deleterious consequences of these infections. Therefore, the goals of this study were to determine the cost and QOL outcomes affecting patients who developed deep wound infections following subaxial dorsal cervical spine fusions.
The authors identified 22 (4.0%) of 551 patients undergoing dorsal cervical fusions who developed deep wound infections requiring surgical debridement. These patients were individually matched with control patients who did not develop infections. Health outcomes were assessed using the EQ-5D, Pain Disability Questionnaire (PDQ), Patient Health Questionnaire (PHQ-9), and visual analog scale (VAS). QOL outcome measures were collected preoperatively and after 6 and 12 months. Health resource utilization was recorded from patient electronic medical records over an average follow-up of 18 months. Direct costs were estimated using Medicare national payment amounts, and indirect costs were based on patients' missed workdays and income.
No significant differences in preoperative QOL scores were found between the 2 cohorts. At 6 months postsurgery, the noninfection cohort had significant pre- to postoperative improvement in EQ-5D (p = 0.02), whereas the infection cohort did not (p = 0.2). The noninfection cohort also had a significantly higher 6-month postoperative EQ-5D scores than the infection cohort (p = 0.04). At 1 year postsurgery, there was no significant difference in EQ-5D scores between the groups. Health care–associated costs for the infection cohort were significantly higher ($16,970 vs $7658; p < 0.0001). Indirect costs for the infection cohort and the noninfection cohort were $6495 and $2756, respectively (p = 0.03). Adjusted for inflation, the total costs for the infection cohort were $21,778 compared with $9159 for the noninfection cohort, reflecting an average cost of $12,619 associated with developing a postoperative deep wound infection (p < 0.0001).
Dorsal cervical infections temporarily decrease patient QOL postoperatively, but with no long-term impact; they do, however, dramatically increase the cost of care. Knowledge of the financial burden of wound infections following dorsal cervical fusion may stimulate the development and use of improved prophylactic and therapeutic techniques to manage this serious complication.
Daniel Lubelski, Nilgun Senol, Michael P. Silverstein, Matthew D. Alvin, Edward C. Benzel, Thomas E. Mroz and Richard Schlenk
The authors investigated quality of life (QOL) outcomes after primary versus revision discectomy.
A retrospective review was performed for all patients who had undergone a primary or revision discectomy at the Cleveland Clinic Center for Spine Health from January 2008 through December 2011. Among patients in the revision cohort, they identified those who needed a second revision discectomy. Patient QOL measures were recorded before and after surgery. These measures included responses to the EQ-5D health questionnaire, Patient Health Questionnaire–9, Pain and Disability Questionnaire, and quality-adjusted life years (QALYs). Cohorts were compared by using independent-sample t-tests and Fisher exact tests for continuous and categorical variables, respectively. Multivariable logistic regression was performed to adjust for confounding.
A total of 196 patients were identified (116 who underwent primary discectomy and 80 who underwent revision discectomy); average follow-up time was 150 days. There were no preoperative QOL differences between groups. Postoperatively, both groups improved significantly in all QOL measures. For QALYs, the primary cohort improved by 0.25 points (p < 0.001) and the revision cohort improved by 0.18 points (p < 0.001). QALYs improved for significantly more patients in the primary than in the revision cohort (76% vs 59%, respectively; p = 0.02), and improvement exceeded the minimum clinically important difference for more patients in the primary cohort (62% vs 45%, respectively; p = 0.03). Of the 80 patients who underwent revision discectomy, yet another recurrent herniation (third herniation) occurred in 14 (17.5%). Of these, 4 patients (28.6%) chose to undergo a second revision discectomy and the other 10 (71.4%) underwent conservative management. For those who underwent a second revision discectomy, QOL worsened according to all questionnaire scores.
QOL, pain and disability, and psychosocial outcomes improved after primary and revision discectomy, but the improvement diminished after revision discectomy.
Presented at the 2012 Joint Spine Section Meeting
Daniel Lubelski, Kalil G. Abdullah, Amy S. Nowacki, Matthew D. Alvin, Michael P. Steinmetz, Srita Chakka, Yumeng Li, Nicholas Gajewski, Edward C. Benzel and Thomas E. Mroz
The goal of this study was to compare the urological complications in patients after anterior lumbar interbody fusion (ALIF) with and without the use of recombinant human bone morphogenetic protein–2 (rhBMP-2).
The authors retrospectively reviewed the medical records of all patients who underwent ALIF with and without rhBMP-2 between January 2002 and August 2010. Patient demographic, operative, and complication information was analyzed. Male patients who underwent ALIF between L-4 and S-1 were contacted to assess postoperative urological complications.
Of the 110 male patients who underwent ALIF and were included in this study, 59 were treated with rhBMP-2 and 51 did not receive rhBMP-2. The mean follow-up duration was 17.5 months for the rhBMP-2 group and 30.8 months for the control group. No difference was found regarding the total number of urological complications in the rhBMP-2 group versus the control group (22% vs 20%, respectively; p = 1.0) or for retrograde ejaculation specifically (8% vs 8%, respectively; p = 1.0).
In this study, the use of rhBMP-2 with ALIF surgery was not associated with an increased incidence of urological complications and retrograde ejaculation when compared with control ALIF without rhBMP-2. Further prospective analyses that specifically look at these complications are warranted.