Effectiveness of Radial Extracorporeal Shockwave Therapy in Patients with Acute Low Back Pain-Randomized Controlled Trial.

The aim of this study was to investigate the effect of radial extracorporeal shockwave therapy (rESWT) primarily on acute lumbar back pain (aLBP), and secondarily on physical function and quality of life. This randomized, placebo-controlled, single-blinded trial with 12-week follow-up (FU) randomized 63 patients with aLBP 1:1 into two groups receiving either rESWT (intervention) or sham rESWT (placebo) with a manipulated shockwave head not delivering any shockwaves. Both, rESWT and sham procedure were carried out eight times for four weeks. Both groups received additional analgesics and physiotherapy twice a week. Primary patient-reported outcome measure (PROM) was the visual analogue scale for aLBP (VAS-LBP). Secondary PROMs included the Oswestry disability index (ODI), Roland and Morris Disability Questionnaire (RDQ), EuroQol EQ-5D-3L, and the Beck Depression Index (BDI-II). Primary endpoint was a between-arm comparison of mean changes in VAS-LBP from baseline to final FU. At randomization, there were no differences between the two groups in relation to age and PROMs. Both groups showed significant improvement in all PROMs at final FU. VAS-LBP declined by 60.7% (p < 0.001) in the intervention and by 86.4% (p < 0.001) in the sham group. The intervention group showed significantly less pain relief after 4 and 12 weeks. The EQ-5D submodality pain showed significantly inferior results for the intervention (1.5 (0.58)) compared to the sham group (1.1 (0.33)) (p < 0.014) after eight weeks. No significant intergroup differences were observed for RDQ, ODI or BDI-II. Additional rESWT alongside conventional guideline therapy in aLBP does not have any significant effects on pain intensity, physical function, or quality of life. To the best of our knowledge, this is the first study with a high level of evidence reporting the efficacy of rESWT in aLBP treatment and will be a future basis for decision-making.

Cervical Spinal Fusion: 16-Year Trends in Epidemiology, Indications, and In-Hospital Outcomes by Surgical Approach.

BACKGROUND: The rate of cervical spinal fusion has been increasing significantly. However, there is a paucity of literature describing trends based on surgical approach using complete population databases. We investigated the approach-based trends in epidemiology, indications, and in-hospital outcomes of cervical spinal fusion. METHODS: New York's Statewide Planning and Research Cooperative System database was queried to identify patients who underwent primary subaxial cervical fusion from 1997 to 2012. Demographic and clinical information was obtained. Subgroup analyses were performed based on surgical approach: anterior (A), posterior (P), and circumferential (C). RESULTS: A total of 87,045 cervical fusions were included. Over the study period, the population-adjusted annual fusion rate increased from 23.7 to 50.6 per 100,000 population (P < 0.001). A fusion was most common (85.2%), followed by P (12.3%), and C (2.5%). Mean ages were 49.8 ± 11.9, 59.9 ± 15.2, and 55.1 ± 14.5 years (P < 0.001), respectively. Although rates remained steady among younger patients, they increased for older patients. Overall, degenerative conditions were the predominant indications for surgery and increased in rate over time. The mean length of stay was: A, 3.1 ± 10.5; P, 9.1 ± 14.1; and C, 14.1 ± 22.5 days (P < 0.001). Rates of in-hospital complications were A, 3.0%; P, 10.5%; and C, 18.9% (P < 0.001), and mortality was A, 0.3%, P, 1.8%, and C, 2.5% (P < 0.001). CONCLUSIONS: The rate of subaxial spinal fusions increased 114% from 1997 to 2012 in New York State. Rates remained stable in younger patients but increased in the older population. Preoperative indications and postoperative courses differed significantly among the various approaches, with patients undergoing anterior fusion having better short-term outcomes.

Postoperative Emergency Department Utilization and Hospital Readmission After Cervical Spine Arthrodesis: Rates, Trends, Causes, and Risk Factors.

STUDY DESIGN: Retrospective state database analysis. OBJECTIVE: To quantify the 30- and 90-day emergency department (ED) utilization and inpatient readmission rates after primary cervical arthrodesis, to stratify these findings by surgical approach, and to describe risk factors and conditions precipitating these events. SUMMARY OF BACKGROUND DATA: Limited data exist on ED utilization and hospital readmission rates after cervical spine arthrodesis. METHODS: The New York State all-payer health-care database was queried to identify all 87,045 patients who underwent primary subaxial cervical arthrodesis from 1997 through 2012. Demographic data and clinical information were extracted. Readmission data were available for the entire study period, whereas ED utilization data collection began later and was therefore analyzed starting in 2005. Incidences of these events within 30 and 90 days of discharge as well as trends over time were tabulated. The conditions prompting these encounters were also collected. Data were analyzed with respect to surgical approach. RESULTS: The hospital readmission rate was 4.2% at 30 days and 6.2% at 90 days postoperatively. Approximately 6.2% of patients were managed in the ED without inpatient admission within 30 days and 11.3% within 90 days of surgery. The most common conditions prompting such events were dysphagia or dysphonia, respiratory complications, and infection. ED utilization and readmission rates were lowest after anterior surgeries. A preoperative Charlson Comorbidity Index of 1 or greater and traumatic pathologies were associated with increased risk of subsequent ED utilization or hospital readmission. Thirty-day hospital readmission rates declined after 2010, whereas 30-day ED utilization continued to increase. CONCLUSION: Patient comorbidities, traumatic pathologies, and surgical approach are associated with increased postoperative complications. Anterior procedures carry the lowest risk, followed by posterior and then circumferential. Awareness of these findings should help to encourage development of strategies to minimize the rate of postoperative ED utilization and hospital readmission. LEVEL OF EVIDENCE: 3.

C2 Bone Erosion Secondary to Iatrogenic Pseudomeningocele: A Case Report and Description of a Novel Surgical Technique.

BACKGROUND: Pseudomeningoceles are a rare cause of bone erosions. Development of such erosions in the C2 vertebral body and the odontoid process can lead to life-threatening instability. Treatment options to regain stability include atlantoaxial and occipitocervical fusion. For patients with a history of Chiari decompression and large C2 lesions, common fusion techniques are not always feasible. In addition, fusion surgery sacrifices physiologic motion and is therefore a disabling procedure, especially for young and active patients. CASE DESCRIPTION: We report a novel combined open operative and subsequent minimal invasive filling technique of several instable osteolytic/cystic areas within the C2 vertebra of a 28-year-old woman. The underlying cause for the lesions was a pseudomeningocele communicating with the vertebral body. This was an incidental finding 15 years after foramen magnum decompression with C1 and partial C2 laminectomy for Chiari malformation. Novel treatment included open posterior surgery with total laminectomy of the remaining C2 arch and refilling the odontoid with viscous beta tricalcium phosphate and polymethylmethacrylate bone cement. Postoperative 6- and 12-month follow-up computed tomography imaging showed a stable incorporation of the filling. CONCLUSIONS: Life-threatening fractures at the occipitocervical junction are rare and often are due to high-impact trauma. Osteolytic changes at those bone compartments are a potential cause for pathologic fractures during normal daily activities. In this case, increased pressure on the bone due to a pseudomeningocele resulted in slow bone loss without symptoms. A novel combined technique of bone filling was applied successfully to stabilize the C2 vertebral bone.

Single-Level Lateral Lumbar Interbody Fusion for the Treatment of Adjacent Segment Disease: A Retrospective Two-Center Study.

STUDY DESIGN: A retrospective case series. OBJECTIVE: The aim of this study was to assess the postoperative outcome after single-level lateral lumbar interbody fusion (LLIF) for adjacent segment disease (ASD). SUMMARY OF BACKGROUND DATA: Although there is a plethora of literature on ASD following traditional arthrodesis techniques, literature on ASD following LLIF is limited. Vice versa, the surgical outcome after LLIF for the treatment of ASD remains to be elucidated. METHODS: Patients who underwent single-level LLIF for ASD at two institutions (March 2006-April 2012) were included, and the medical records, operative reports, radiographic imaging studies, and office records reviewed. RESULTS: Out of 523 LLIF patients, 52 met the inclusion criteria, and were postoperatively followed for 16.1 ±â€Š9.8 months (range: 5-44). When comparing the pre-operative data with both the first and most recent follow-up postoperatively, LLIF resulted in a reduction in back pain (P < 0.001, and P < 0.001, respectively) and leg pain (P < 0.001, and P < 0.001, respectively), increase in segmental lordosis (P = 0.003, and P = 0.014, respectively), decrease in segmental coronal angulation (P < 0.001, and P = 0.003, respectively), and increase in intervertebral height (P < 0.001, and P < 0.001, respectively) at the surgical level. The reoperation rate related to the LLIF procedure was 21.2% (11/52), which was performed after an average of 14.6 ±â€Š10.1 months (range: 3.3-31.0). Eight out of 11 patients (72.7%) in the reoperation subgroup underwent standalone LLIF, whereas only 23 out of 41 patients (56.1%) without a reoperation underwent standalone LLIF (P = 0.491). There was a trend toward a higher fusion rate in patients who underwent circumferential fusion than the standalone subgroup (87.5% vs. 53.8%; P = 0.173). CONCLUSION: LLIF may be an effective surgical treatment option for ASD with regard to both the clinical and radiographic outcome in a large proportion of cases. Although standalone LLIF is associated with a narrower spectrum of adverse effects than circumferential fusion, posterior instrumentation may be necessary to increase segmental stability. LEVEL OF EVIDENCE: 4.

Demographic, Clinical, and Operative Factors Affecting Long-Term Revision Rates After Cervical Spine Arthrodesis.

BACKGROUND: Limited data exist on long-term revision rates following cervical spine arthrodeses. The purposes of this study were to define reoperation rates after primary cervical arthrodeses and to identify risk factors for revisions. METHODS: New York State's all-payer health-care database was queried to identify all primary subaxial cervical arthrodeses occurring in the 16 years from 1997 through 2012. A total of 87,042 patients were included in the study cohort. Demographic information was extracted. Patients' preoperative medical comorbidities, surgical indications, and operative approaches were assembled using codes from the ICD-9-CM (International Classification of Diseases, Ninth Revision, Clinical Modification). The cohort was followed to revision surgical procedures, death, or the end of the study period. All subsequent contiguous spinal arthrodeses, including in the subaxial cervical spine, were considered revisions. The overall revision risk and the risk associated with various preoperative characteristics, surgical indications, and operative approaches were assessed using a Cox proportional hazard model. RESULTS: During the study period, 6,721 patients (7.7%) underwent revision. The median time to revision was 24.5 months. The probability of undergoing at least one revision by 192 months was 12.6%. Arthrodeses performed via anterior-only approaches had a significantly higher probability of revision (p < 0.001) at 13.4% (95% confidence interval [95% CI], 12.9% to 13.9%) than those performed via posterior approaches at 7.4% (95% CI, 6.6% to 8.4%) or circumferential (anterior and posterior) approaches at 5.2% (95% CI, 4.0% to 6.8%). This relationship persisted in multivariate analysis; compared with anterior surgical procedures, there was a significantly lower risk of revision (p < 0.001) for posterior surgical approaches at a hazard ratio of 0.76 (95% CI, 0.69 to 0.84) and circumferential approaches at a hazard ratio of 0.53 (95% CI, 0.42 to 0.66). Patient age of 18 to 34 years, white race, insurance status of Workers' Compensation or Medicare, and surgical procedures for spinal stenosis, spondylosis, deformity, and neoplasm were associated with elevated revision risk. Arthrodeses spanning few levels and those performed for fractures had a lower revision risk. CONCLUSIONS: Primary subaxial cervical spine arthrodeses had a probability of revision approaching 13% over a 16-year period, with elevated reoperation rates in patients undergoing anterior-only surgical procedures. Age, race, insurance status, surgical indication, and number of spinal levels included in the arthrodesis were also associated with reoperation risk. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

A Novel Radiographic Indicator of Developmental Cervical Stenosis.

BACKGROUND: Developmental cervical stenosis of the spinal canal predisposes patients to neural compression and loss of function. The Torg-Pavlov ratio has been shown to provide high sensitivity but low specificity for identifying developmental cervical stenosis. A more sensitive and specific radiographic index has not been reported to our knowledge. The objective of this study was to develop and provide an objective, sensitive, and specific radiographic index to assess for developmental cervical stenosis. METHODS: The C3 through C6 levels of the cervical spine were analyzed on lateral radiographs of 150 adult patients to determine the spinolaminar line-to-lateral mass distance (SL), lateral mass-to-posterior vertebral body distance (LM), spinolaminar line-to-vertebral body (canal) diameter (CD), and vertebral body diameter (VB). Ratios of these measurements were calculated to eliminate magnification effects. The corresponding true spinal canal diameter was measured using computed tomography (CT) midsagittal sections. Receiver operating characteristic (ROC) curve analysis was performed to identify a radiographic measurement ratio with optimal sensitivity and specificity, using a true canal diameter of <12 mm to define developmental cervical stenosis. RESULTS: Several of the measured ratios demonstrated a strong correlation with the true canal diameter at all cervical levels. However, ROC curve analysis showed that only an LM/CD ratio of ≥0.735 indicated a canal diameter of <12 mm (developmental cervical stenosis). The sensitivity of this ratio at C5 was 83% and its specificity at C5 was 74%. An LM/CD ratio of ≥0.735 measured only at the C5 level also indicated developmental cervical stenosis at any cervical level from C3 through C6 with 76% sensitivity and 80% sensitivity. Other ratios, including the Torg-Pavlov ratio, did not demonstrate an adequate statistical profile to indicate developmental cervical stenosis. The accuracy of the LM/CD ratio was not adversely affected by the patient's sex. CONCLUSIONS: This analysis provided a novel index for identifying developmental cervical stenosis: the C5 lateral mass/canal diameter (LM/CD) ratio. We believe that this ratio is the best radiographic measurement available to screen for developmental cervical stenosis in the adult spine patient population. It provides an objective radiographic screening tool for physicians to detect developmental cervical stenosis and decide whether additional imaging or surgical referral is appropriate. LEVEL OF EVIDENCE: Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Atlantoaxial Fusion: Sixteen Years of Epidemiology, Indications, and Complications in New York State.

STUDY DESIGN: A retrospective state database analysis. OBJECTIVE: The aim of this study was to describe the epidemiology and complications of as well as indications for primary isolated atlantoaxial fusion. SUMMARY OF BACKGROUND DATA: Atlantoaxial fusion involves unique indications, techniques, and complications. There is limited epidemiologic literature focused specifically on this procedure. METHODS: New York's Statewide Planning and Research Cooperative System database, an all-payer hospitalization reporting system, was queried to identify all patients undergoing primary isolated atlantoaxial fusion in the state from 1997 to 2012. Demographic and clinical data were extracted and analyzed. United States Census Bureau figures were used to calculate population-adjusted surgical rates. RESULTS: One thousand five hundred fifty-nine patients underwent isolated primary atlantoaxial fusion during the study period. The overall population-adjusted annual surgical rate did not change significantly over time. By 2012, individuals aged ≥70 years had the highest incidence of surgery [2.37 per 100,000 population; 95% confidence interval (95% CI) 1.68-3.07]. Medicare was the most common payer (44.0% of claims). Approximately 85% of patients had a Charlson/Deyo Comorbidity Index of zero or one. Over time, a significantly lower proportion of atlantoaxial fusions were attributable to rheumatic disease, and a significantly higher proportion were due to fracture. By 2012, management of fractures was the most common indication for C1-C2 fusion (44.1% of cases). Dysphagia or dysphonia occurred after 0.8% of cases, dural tear after 0.3%, infection after 0.5%, and seroma, hematoma, or hemorrhage after 0.5%. In-hospital mortality was 2.7%, of which 76% had fracture as the surgical indication. CONCLUSION: Isolated atlantoaxial fusions have been performed at a stable, low level over the past 16 years in New York. Although most of these patients are relatively healthy pre-operatively, approximately one in 10 experience an in-hospital complication and nearly 3% die in-hospital. Knowledge of these risks will hopefully spur further efforts to minimize them and allow for more accurate counseling of patients and their families. LEVEL OF EVIDENCE: 4.