Epidemiological study using national administrative data.
To evaluate the temporal trends in on-label and off-label bone morphogenetic protein (BMP) usage in primary and revision spine fusion by ...spine region and surgical approach, and nonspine applications in the United States from 2002 to 2007.
The prevalence of BMP usage for spine fusion has been on the rise, but its use has not been stratified by surgical approach, particularly for lumbar fusion where it has only been Food And Drug Administration-approved for anterior lumbar interbody fusion (ALIF).
The prevalence of BMP usage in the United States was evaluated using the Nationwide Inpatient Sample between October 1, 2002 and December 31, 2007. The Nationwide Inpatient Sample is the single largest all-payer inpatient care database in the United States. The principal procedure associated with BMP use was determined, and the prevalence of BMP use was calculated for various population subgroups.
A total of 340,251 inpatient procedures with BMP usage were identified. Between 2003 and 2007, the annual number of procedures involving BMP increased by 4.3-fold from 23,900 to 103,194. Spine fusion accounted for the vast majority (92.8%) of principal procedures with BMP. The predominant use of BMP was in primary posterior lumbar interbody fusion or transforaminal lumbar interbody fusion (PLIF/TLIF) (30.0%), followed by primary posterolateral spine fusion (20.4%), primary ALIF (16.6%), primary cervical fusions (13.6%), and primary thoracolumbar fusions (3.9%). Of primary ALIF with BMP, 19.3% did not involve the implantation of an interbody device.
At least 85% of principal procedures using BMP were for off-label applications. With uncertainty regarding the risks of using BMP in certain off-label applications, further research will be needed to better define the appropriate indications. Our study also demonstrates that disparities in the differential rates of BMP use exist in the spine fusion population.
Abstract Background context The impact of lumbar spinal surgery is commonly evaluated with three patient-reported outcome measures: Oswestry Disability Index (ODI), the physical component summary ...(PCS) of the Short Form of the Medical Outcomes Study (SF-36), and pain scales. A minimum clinically important difference (MCID) is a threshold used to measure the effect of clinical treatments. Variable threshold values have been proposed as MCID for those instruments despite a lack of agreement on the optimal MCID calculation method. Purpose This study has three purposes. First, to illustrate the range of values obtained by common anchor-based and distribution-based methods to calculate MCID. Second, to determine a statistically sound and clinically meaningful MCID for ODI, PCS, back pain scale, and leg pain scale in lumbar spine surgery patients. Third, to compare the discriminative ability of two anchors: a global health assessment and a rating of satisfaction with the results of the surgery. Study design This study is a review of prospectively collected patient-reported outcomes data. Patient sample A total of 454 patients from a large database of surgeries performed by the Lumbar Spine Study Group with a 1-year follow-up on either ODI or PCS were included in the study. Outcome measures Preoperative and 1-year postoperative scores for ODI, PCS, back pain scale, leg pain scale, health transition item (HTI) of the SF-36, and Satisfaction with Results scales. Methods ODI, SF-36, and pain scales were administered before and 1 year after spinal surgery. Several candidate MCID calculation methods were applied to the data and the resulting values were compared. The HTI of the SF-36 was used as the anchor and compared with a second anchor (Satisfaction with Results scale). Results Potential MCID calculations yielded a range of values: fivefold for ODI, PCS, and leg pain, 10-fold for back pain. Threshold values obtained with the two anchors were very similar. Conclusions The minimum detectable change (MDC) appears as a statistically and clinically appropriate MCID value. MCID values in this sample were 12.8 points for ODI, 4.9 points for PCS, 1.2 points for back pain, and 1.6 points for leg pain.
Longitudinal cohort.
To determine the minimum clinically important difference (MCID) of the Scoliosis Research Society (SRS)-22 Appearance, Activity, and Pain domains in patients with adolescent ...idiopathic scoliosis undergoing surgical correction of their spinal deformity.
The MCID, a threshold of improvement that is clinically relevant to the individual patient, is increasingly used to evaluate treatment effectiveness. MCID values for the SRS-22 domains have not been determined.
Patients with adolescent idiopathic scoliosis who underwent surgical correction and had completed SRS-22 before operation and the SRS-30 and Scoliosis Appearance Questionnaire (SAQ) at 1 year after operation from a multicenter database for pediatric scoliosis were identified. The SAQ is a modification of the Walter Reed Visual Assessment Scale and is used to assess the patient's perception of their spinal deformity. Paired sample t tests were used to compare preoperative and 1-year postoperative scores. Spearman correlations were used to evaluate associations between domain scores and summed responses to anchors for Appearance, Activity, and Pain. MCID values for the SRS-22 domains were determined using receiver operating characteristic curve analysis, with summed responses to anchor questions 23 to 30 of the SRS-30 and items 26 and 32 of the SAQ.
There were 735 women and 152 men with a mean age of 14.3 years and a mean Cobb angle of 53°. There was a statistically significant difference between paired preoperative and 1-year SRS domain scores. Analysis of variance showed a statistically significant difference between the summed responses to the anchors. The MCID was 0.20 for the Pain domain (area under the curve AUC = 0.723), 0.08 for Activity (AUC = 0.648), and 0.98 for Appearance (AUC = 0.629). The MCID for activity was less than the standard error of measurement.
The MCID for the Pain domain was 0.20 and 0.98 for Appearance. Because these patients were generally in good health, a minimal though significant change in activity was observed, such that the calculated MCID was within the measurement error. As expected, the largest and most important change was in the Appearance domain. Future studies are needed to determine the MCID for the mental domain and the total SRS score and to further validate the MCID values in this study.
Purpose
To report the incidence of cancer in a cohort of adolescent idiopathic scoliosis (AIS) patients treated 25 years previously.
Methods
215 consecutive AIS patients treated between 1983 and 1990 ...were identified and requested to return for clinical and radiographic examination. The incidence of cancer was determined through chart review and follow-up interviews. Using the original radiographic log file that included patient position, mAs, kV and the total number of X-rays taken, a radiation physicist calculated the total radiation dose during treatment and follow-up adjusted for BMI and sex.
Results
From the original cohort of 215 consecutive AIS patients, radiation information was available in 211 of the patients, and medical charts were available in 209 AIS patients. 170 (83 %) of the 205 AIS patients participated in the follow-up study with questionnaires. The calculated mean total radiation exposure was 0.8–1.4 mSV per examination and 2.4–5.6 mSv/year. An average of 16 radiographs were taken during the treatment period. Nine AIS patients developed cancer, mostly breast (3) and endometrial (4). The AIS patients had a relative risk of 4.8 (CI 2.3–5.8,
p
< 0.000) for developing cancer compared to the normal Danish population.
Conclusions
The overall cancer rate in this AIS cohort was 4.3 % which is five times higher than compared to the age-matched Danish population, and endometrial and breast cancer was most frequent. The radiation dose applied to the patients in this study, is comparable to modern equipment. This is to our knowledge the first study to report increased rates of endometrial cancers in a cohort of AIS patients, and future attention is needed to reduce the radiation dose distributed to the AIS patients both pre-operatively and during surgery.
Longitudinal cohort.
To establish minimum clinically important difference (MCID) threshold values for Scoliosis Research Society-22R (SRS-22R) domains in patients with adult spinal deformity ...undergoing surgical correction.
The SRS-22R has been shown to be reliable, valid and responsive to change in patients with adult spinal deformity undergoing surgery. The MCID quantifies a threshold of improvement that is clinically relevant to the patient.
Patients in a prospective database who completed the SRS-22R preoperatively and the SRS-30 1 year postoperatively were identified. Answers to the last 8 questions of the SRS-30 were used as anchors to determine MCID for the pain, appearance and activity domains, subscore, and total score using receiver-operating-characteristic curve analysis. Calculations of MCID using distribution-based methods were also done.
A total of 1321 patients were included in the analysis; 83% were females and 10% were smokers. Mean age was 53 years. Mean body mass index was 26.3 kg/m. Mean preoperative SRS-22R appearance score was 2.50 improving to 3.62 at 1 year postoperatively (P < 0.001). Mean preoperative SRS-22R activity score was 2.96 and it improved to 3.33 at 1 year postoperatively (P < 0.001). Mean preoperative SRS-22R pain score was 2.73 improving to 3.60 at 1 year postoperatively (P < 0.001). Mean preoperative total score was 2.93 and it improved to 3.65 at 1 year postoperatively (P < 0.001). There was a statistically significant difference in domain scores among the responses to the anchors (P < 0.001). The different calculation methods yielded MCID values of 0.19 to 1.23 for appearance, 0.23 to 0.60 for activity, 0.24 to 0.57 for pain, 0.16 to 0.43 for subscore, and 0.17 to 0.71 for total score.
When combined with previous reports, the results of this study in a population with adult spinal deformity undergoing surgical treatment show MCID for SRS-22 scores can be estimated as 0.4. This corresponds to a change of 1 interval in 2 of the 5 questions for a single domain.
2.
Cost effectiveness analysis for single-level instrumented fusion during a 5-year postoperative interval.
To determine the cost/quality-adjusted life year (QALY) gained for single-level instrumented ...posterolateral lumbar fusion for degenerative lumbar spine conditions during a 5-year period.
Cost/QALY has become a standard measure among healthcare economists because it is generic and can be used across medical treatments. Prior studies have reported widely variable estimates of cost/QALY for lumbar spine fusion. This variability may be related to factors including study design, sample population, baseline assumptions, and length of the observation period.
To determine QALY, the Short Form 6D (SF-6D), a utility index derived from the Short Form (36) Health Survey (SF-36) was used. Cost analysis was performed based on actual reimbursements from third-party payors, including those for the index surgical procedure, treatment of complications, emergency room outpatient visits, and revision surgery. A second cost analysis using only the contemporaneous Medicare Fee schedule was also performed, in addition to a subanalysis including indirect costs from days off work.
The mean SF-6D health utility value showed a gradual increase throughout the follow-up period. The mean health utility value gained in each year postoperatively was 0.12, 0.14, 0.13, 0.15, and 0.15, for a cumulative 0.69 QALY improvement during the 5-year interval. Mean direct medical costs based on actual reimbursements for 5 years after surgery, including the index and revision procedures, was $22,708. The resultant cost per QALY gained at the 5-year postoperative interval was $33,018. The analogous mean direct cost based on Medicare reimbursement for 5 years was $20,669, with a resultant cost per QALY gained of $30,053. The mean total work productivity cost for 5 years was $14,377. The resultant total cost (direct and indirect) per QALY gained ranged from $53,949 to $53,914 at 5 years postoperatively.
In the future, surgeons will need to demonstrate cost-effectiveness as well as clinical efficacy in order to justify payment for medical and surgical interventions, including lumbar spine fusion. This study indicates that at 5-year follow-up, single-level instrumented posterolateral spine fusion is both effective and durable, resulting in a favorable cost/QALY gain compared to other widely accepted healthcare interventions.
Abstract Background Context The Neck Disability Index (NDI), the short form-36 (SF-36) physical component summary (PCS), and pain scales for arm and neck pain are increasingly used to evaluate ...treatment effectiveness after cervical spine surgery. The minimum clinically important difference (MCID) is a threshold of improvement that is clinically relevant to the patient. However, the true goal is to provide the patient with a substantial clinical benefit (SCB). Purpose This study determines the MCID and SCB using common anchor-based methods for NDI, PCS, and pain scales for arm and neck pain in patients undergoing cervical spine fusion for degenerative disorders. Study Design/Setting The study setting is a longitudinal cohort in a multisurgeon spine specialty clinic. Patient sample The sample comprises 505 patients who underwent a cervical fusion for degenerative spine conditions and who have prospectively collected outcome scores with a minimum 1-year follow-up. Outcome Measures The outcome measures of the study were NDI, SF-36, and numeric rating scales for arm and neck pain. Methods The MCID and SCB values for NDI, PCS, and pain scales for arm and neck pain were determined using receiver operating characteristic (ROC) curve analysis with the Health Transition Item of the SF-36 as an anchor. The Health Transition Item asks a patient “Compared to one year ago, how would you rate your health in general now?” with answers ranging from “Much Better,” “Somewhat Better,” “About the Same,” “Somewhat Worse,” to “Much Worse.” An ROC curve was constructed for each measure. The ROC curve–derived MCID was the change score with equal sensitivity and specificity to distinguish the “Somewhat Better” from the “About the Same” patients. The ROC curve–derived SCB was the change score with equal sensitivity and specificity to distinguish the “Much Better” from the “Somewhat Better” patients. Distribution-based methods including the standard error of the mean and the minimum detectable change were also used to calculate MCID. Results The calculated MCID is 7.5 for the NDI, 4.1 for SF-36 PCS, and 2.5 for arm and neck pain. The calculated SCB is 9.5 for the NDI, 6.5 for SF-36 PCS, and 3.5 for arm and neck pain. Conclusions Patients with an eight-point decrease in NDI, a 4.1-point increase in PCS, and a three-point decrease in arm or neck pain can detect a minimally clinically important change. Patients with a 10-point decrease in NDI, a 6.5-point increase in PCS, and a four-point decrease in arm or neck pain can detect an SCB after cervical spine fusion.
Validated health-related quality-of-life measures have become important standards in the evaluation of the outcomes of lumbar spine surgery. However, there are few well-defined criteria for clinical ...success based on these measures. The minimum clinically important difference is an important demarcation, but it could be considered a floor value rather than a goal in defining clinical success. Therefore, we sought to define thresholds of substantial clinical benefit for commonly used health-related quality-of-life measures following lumbar spine arthrodesis.
Prospectively collected preoperative and one-year postoperative health-related quality-of-life measures from 357 patients who were managed with lumbar spine arthrodesis for the treatment of degenerative conditions were identified. Candidate substantial clinical benefit thresholds for the Short Form-36 physical component score, Oswestry Disability Index, and back and leg pain numeric rating scales were identified with use of receiver operating characteristic curve analysis. Receiver operating characteristic curves were used to discriminate between patients who reported being "much better" or "about the same" with use of the validated Short Form-36 health transition item and between those who reported being "mostly satisfied" or "unsure" with use of a nonvalidated but more surgery-specific satisfaction-with-results survey. For each health-related quality-of-life measure, three response parameters were used: net change, percent change, and raw score at the time of the one-year follow-up.
Substantial clinical benefit thresholds for the Short Form-36 physical component score were a 6.2-point net improvement, a 19.4% improvement, or a final raw score of > or = 35.1 points. Substantial clinical benefit thresholds for the Oswestry Disability Index were an 18.8-point net improvement, a 36.8% improvement, or a final raw score of < 31.3 points. Substantial clinical benefit thresholds for the back pain and leg pain numeric rating scales were a 2.5-point net improvement or a final raw score of < 3.5 points. Substantial clinical benefit thresholds for percent change were 41.4% for the back pain numeric rating scale and 38.8% for the leg pain numeric rating scale.
We believe that thresholds of substantial clinical benefit for commonly used health-related quality-of-life measures following lumbar spine arthrodesis are important as they describe a magnitude of change that the patient recognizes as a major improvement.
Background
Pain control is essential to successful total shoulder arthroplasty (TSA).
Materials and methods
This non-blinded, randomized clinical trial compared shoulder pain, narcotic use, ...interscalene (IS) block application time, and costs in 76 subjects who were randomly assigned to receive either a single injection IS nerve block of 10 cc (133 mg) liposomal bupivacaine mixed with 10 cc of 0.5% bupivacaine (Group 1), or 20 cc of 0.5% ropivacaine direct injection combined with an indwelling IS nerve block catheter delivering 0.2% ropivacaine at a continual 4 cc/h infusion for the initial 3 post-operative days (Group 2). Surgical time, local anesthesia duration, hospital stay length, morphine milligram equivalents (MME) consumed, worst shoulder pain at 24, 48 and 72 h, and complications were recorded. Patient reported function, pain and activity level surveys were completed before, and 6-week post-TSA (
P
< 0.05).
Results
Group 1 had less pain 24-h (0.72 ± 0.8 vs. 3.4 ± 2.9,
p
< 0.0001) and 48-h (2.5 ± 2.2 vs. 4.8 ± 2.6,
p
= 0.005) post-TSA. At 24-h post-TSA, MME consumption was similar (Group 1 = 4.5 ± 6.4 vs. Group 2 = 3.7 ± 3.8,
p
= 0.54), but was lower for Group 1 at 48 h (0.0 ± 0.0 vs. 0.64 ± 0.99,
p
= 0.001). Group 2 had longer IS block application time (10.00 ± 4.6 min vs. 4.84 ± 2.7 min,
p
< 0.0001). Only group 2 had a strong relationship between MME consumption over the first 24-h post-TSA and pain 24-h post-TSA (
r
= 0.76,
p
< 0.0001), a moderate relationship with pain 48-h post-TSA (
r
= 0.59,
P
= 0.001), and a weak relationship with pain 72-h post-TSA (
r
= 0.44,
P
= 0.02). Significant relationships for these variables were not observed for Group 1 (
r
≤ 0.30,
p
≥ 0.23). Group 1 IS block costs were less/patient than Group 2 ($190.17 vs. $357.12 USD).
Conclusion
A single shot, liposomal bupivacaine interscalene nerve block provided better post-TSA pain control with less narcotic consumption, less time for administration and less healthcare system cost compared to interscalene nerve block using a continuous indwelling catheter.
Level of evidence
Level I, Prospective, Randomized.
Propensity-matched case-control study.
To examine the impact of compensation status on clinical outcomes after lumbar spine fusion.
Workers' compensation has been associated with inferior outcomes ...after treatment of low back pain. However, patients receiving other forms of compensation, such as long-term disability or government-supported insurance, have not been studied independently.
Patients with complete preoperative and 2-year postoperative data, including Oswestry disability index, 36-item short form health survey, and numeric rating scales for back and leg pain, after 1- or 2-level posterolateral lumbar fusion from a single spine surgery practice, were retrospectively identified. Fifty-nine patients 50 years or younger receiving disability compensation and 38 patients receiving workers' compensation were identified from 1144 patients with complete outcome measures. Propensity scoring was used to match cohorts not receiving compensation. Each group was matched for sex, age, smoking status, body mass index, surgical indication, number of levels fused, and baseline outcome measures. Fifty-one and 37 matched pairs were successfully identified for disability and workers' compensation cohorts, respectively.
Consistent with propensity matching, no statistically significant difference between cohorts was observed for demographics and baseline outcome measures. At 2-year follow-up, the disability compensation group demonstrated similar degrees of improvement for all outcome measures compared with its matched nondisability cohort, whereas the workers' compensation group demonstrated less improvement than its matched cohort.
This study demonstrates a difference in outcomes after lumbar spinal fusion between long-term disability and workers' compensation populations. Although, these populations achieve only marginal improvement, it seems that the type of compensation status influences outcome. Workers' compensation has a clear, negative influence on outcome when compared with controls, whereas well-selected patients receiving disability compensation seem more likely to benefit from lumbar fusion. Therefore, surgeons and researchers alike should not include disability compensation patients in the same cohort as patients on workers' compensation.
