Minimally Invasive Revision of Luque Plate Instrumentation: A Case Report.

Extension of existing spinal fusions may necessitate the removal of or linkage to prior constructs. Knowledge of previously placed instrumentation is critical to success in these revision scenarios. The Luque spinal instrumentation system, developed in the late 1980s, is a legacy pedicle screw and plate system that may be encountered during revision operations today. A 67-year-old male with a remote history of L4-S1 fusion with Luque instrumentation presented with bilateral lower extremity neurogenic claudication due to adjacent segment disease at L3-4. Decompression and extension of fusion to the L3-4 level were performed using minimally invasive techniques. Of note, posterior instrumentation was extended by removing prior L4 pedicle screws with a 7 mm female hexagonal driver through tubular retractors, leaving the Luque plates in place, placing modern pedicle screws at L4 (through the plates) and L3, and linking these with standard rods. The surgery and post-operative course were uncomplicated, and the patient experienced complete resolution of his pre-operative claudication symptoms. Extension of prior Luque plate instrumented fusion can be accomplished minimally invasively without removing the plates themselves, resulting in greater operative efficiency and less surgical morbidity.

Pain alleviation and functional improvement: ultra-early patient-reported outcome measures after full endoscopic spine surgery.

OBJECTIVE: Questions regarding anticipated pain improvement and functional recovery postsurgery are frequently posed in preoperative consultations. However, a lack of data characterizing outcomes for the first postoperative days only allows for anecdotal answers. Hence, the assessment of ultra-early patient-reported outcome measures (PROMs) is essential for patient-provider communication and patient satisfaction. The aim of this study was to elucidate this research gap by assessing and characterizing PROMs for the first days after full endoscopic spine surgery (FESS). METHODS: This multicenter study included patients undergoing lumbar FESS from March 2021 to July 2023. After informed consent was provided, data were collected prospectively through a smartphone application. Patients underwent either discectomy or decompression. Analyzed parameters included demographics, surgical details, visual analog scale scores for both back and leg pain, and the Oswestry Disability Index (ODI) score. Data were acquired daily for the 1st postoperative week, as well as after 2 weeks, 3 months, and 6 months. RESULTS: A total of 182 patients were included, of whom 102 underwent FESS discectomy and 80 underwent FESS decompression. Significant differences between the discectomy and decompression groups were found for age (mean 50.45 ± 15.28 years and 63.85 ± 13.25 years, p < 0.001; respectively), sex (p = 0.007), and surgery duration (73.45 ± 45.23 minutes vs 98.05 ± 46.47 minutes, p < 0.001; respectively). Patients in both groups reported a significant amelioration of leg pain on the 1st postoperative day (discectomy group VAS score: 6.2 ± 2.6 vs 2.4 ± 2.9, p < 0.001; decompression group: 5.3 ± 2.8 vs 1.9 ± 2.2, p < 0.001) and of back pain within the 1st postoperative week (discectomy group VAS score: 5.5 ± 2.8 vs 2.8 ± 2.2, p < 0.001; decompression group: 5.2 ± 2.7 vs 3.1 ± 2.4, p < 0.001). ODI score improvement was most pronounced at the 3-month time point (discectomy group: 21.7 ± 9.1 vs 9.3 ± 9.1, p < 0.001; decompression group: 19.3 ± 7.8 vs 9.9 ± 8.3, p < 0.001). For both groups, pain improvement within the 1st week after surgery was highly predictive of later benefits. CONCLUSIONS: Ultra-early PROMs reveal an immediate pain improvement after FESS. While the benefits in pain reduction plateaued within the 1st postoperative week for both groups, functional improvements developed over a more extended period. These results illustrate a biphasic rehabilitation process wherein initial pain alleviation transitions into functional improvement over time.

Assessing the impact of obesity on full endoscopic spine surgery: surgical site infections, surgery durations, early complications, and short-term functional outcomes.

OBJECTIVE: An increasing number of obese patients undergoing elective spine surgery has been reported. Obesity has been associated with a substantially higher number of surgical site infections and a longer surgery duration. However, there is a lack of research investigating the intersection of obesity and full endoscopic spine surgery (FESS) in terms of functional outcomes and complications. The aim of this study was to evaluate wound site infections and functional outcomes following FESS in obese patients. METHODS: Patients undergoing lumbar FESS at the participating institutions from March 2020 to March 2023 for degenerative pathologies were included in the analysis. Patients were divided into obese (BMI > 30 kg/m2) and nonobese (BMI 18-30 kg/m2) groups. Data were collected prospectively using an approved smartphone application for 3 months postsurgery. Parameters included demographics, surgical details, a virtual wound checkup, the visual analog scale for back and leg pain, and the Oswestry Disability Index (ODI) as a functional outcome measure. RESULTS: A total of 118 patients were included in the analysis, with 53 patients in the obese group and 65 in the nonobese group. Group homogeneity was satisfactory regarding patient age (obese vs nonobese: 55.5 ± 14.7 years vs 59.1 ± 17.1 years, p = 0.25) and sex (p = 0.85). No surgical site infection requiring operative revision was reported for either group. No significant differences for blood loss per level (obese vs nonobese: 9.7 ± 16.8 ml vs 8.0 ± 13.3 ml, p = 0.49) or duration of surgery per level (obese vs nonobese: 91.2 ± 57.7 minutes vs 76.8 ± 39.2 minutes, p = 0.44) were reported between groups. Obese patients showed significantly faster improvement regarding ODI (-3.0 ± 9.8 vs 0.7 ± 11.3, p = 0.01) and leg pain (-4.4 ± 3.2 vs -2.9 ± 3.7, p = 0.03) 7 days postsurgery. This effect was no longer significant 90 days postsurgery for either ODI (obese vs nonobese: -11.4 ± 11.4 vs -9.1 ± 9.6, p = 0.24) or leg pain (obese vs nonobese: -4.3 ± 3.9 vs -3.5 ± 3.8, p = 0.28). CONCLUSIONS: The results highlight the effectiveness and safety of lumbar FESS in obese patients. Unlike with open spine surgery, obese patients did not experience significant increases in surgery time or postoperative complications. Interestingly, obese patients demonstrated faster early recovery, as indicated by significantly greater improvements in ODI and leg pain at 7 days after surgery. However, there was no difference in improvement between the groups at 90 days after surgery.

Development of an Endoscopic Spine Surgery Program: Overview and Basic Considerations for Implementation.

Endoscopic spine surgery (ESS) is an innovative technique allowing for minimally invasive, direct visualization of spinal abnormalities. The growth of ESS in the United States has been stunted by high start-up costs, low reimbursement rates, and the steep learning curve associated with mastering endoscopic techniques. Hergrae, we describe the current state and future direction of ESS and provide key action items for ESS program implementation.

Comparative analysis of perioperative characteristics and early outcomes in transforaminal endoscopic lumbar diskectomy: general anesthesia versus conscious sedation.

PURPOSE: To better understand how anesthesia type impacts patient selection and recovery in TELD, we conducted a multicenter prospective study which evaluates the differences in perioperative characteristics and outcomes between patients who underwent TELD with either general anesthesia (GA) or conscious sedation (CS). METHODS: We prospectively collected data from all TELD performed by five neurosurgeons at five different medical centers between February and October of 2022. The study population was dichotomized by anesthesia scheme, creating CS and GA cohorts. This study's primary outcomes were the Oswetry Disability Index (ODI) and the Visual Analog Scale (VAS) for back and leg pain, assessed preoperatively and at 2-week follow-up. RESULTS: A total of 52 patients underwent TELD for symptomatic lumbar disk herniation. Twenty-three patients received conscious sedation with local anesthesia, and 29 patients were operated on under general anesthesia. Patients who received CS were significantly older (60.0 vs. 46.7, p < 0.001) and had lower BMI (28.2 vs. 33.4, p = 0.005) than patients under GA. No intraoperative or anesthetic complications occurred in the CS and GA cohorts. Improvement at 2-week follow-up in ODI, VAS-back, and VAS-leg was greater in patients receiving CS relative to patients under GA, but these differences were not statistically significant. CONCLUSION: In our multicenter prospective analysis of 52 patients undergoing TELD, we found that patients receiving CS were significantly older and had significantly lower BMI compared to patients under GA. On subgroup analysis, no statistically significant differences were found in the improvement of PROMs between patients in the CS and GA group.

Collagen Matrix Inlay Graft for Management of Incidental Durotomy During Full-Endoscopic Lumbar Spine Surgery: Technique and Case Series.

BACKGROUND: Endoscopic spine surgery (ESS) has a reduced rate of incidental durotomy (ID) compared with open spine surgery. However, there are unique challenges regarding the management of ID in ESS due to the single, deep, narrow working corridor and aqueous environment. Here, we present a collagen matrix inlay graft technique for the management of ID encountered during ESS. METHODS: Three patients were identified via medical record review of full ESS where an intraoperative ID was encountered. These were all addressed endoscopically. All surgeries were performed by a single surgeon in the years 2019 to 2023. Patient, operative, and postoperative details, including patient-reported outcomes, were recorded. Briefly, the collagen matrix inlay graft technique included introducing a segment of collagen matrix into the surgical field and manipulating the collagen matrix so that it passed through the durotomy and resided within the dura, plugging the hole. RESULTS: Three IDs were identified out of a total of 295 eligible cases (1.02%). The IDs measured 2 to 2.5 mm in length. For these 3 patients, the duration of hospital stay ranged from 172 to 1,068 minutes. No patients exhibited signs or symptoms of cerebrospinal fluid leak at any postoperative timepoint. At the 6-week postoperative visit, all patients had achieved the minimum clinically important difference in Oswestry Disability Index, and all patients with available visual analog scale scores for leg and low back pain had achieved the cutoff for the minimum clinically important difference. CONCLUSIONS: We presented 3 cases of ID during uniportal full ESS who were repaired using a collagen matrix inlay technique. Prolonged bed rest was avoided, and all patients achieved excellent clinical outcomes without further complication. This technique may also be appropriate for other minimally invasive spine surgery techniques. CLINICAL RELEVANCE: ID is a common and undesirable complication of degenerative lumbar spine surgery. Endoscopic ID repair techniques provide an option to avoid conversion to open or tubular surgery for the management of ID.

Device profile of the FlareHawk interbody fusion system, an endplate-conforming multi-planar expandable lumbar interbody fusion cage.

INTRODUCTION: The FlareHawk Interbody Fusion System is a family of lumbar interbody fusion devices (IBFDs) that include FlareHawk7, FlareHawk9, FlareHawk11, TiHawk7, TiHawk9, and TiHawk11. These IBFDs offer a new line of multi-planar expandable interbody devices designed to provide mechanical stability, promote arthrodesis, and allow for restoration of disc height and lordosis through a minimal insertion profile during standard open and minimally invasive posterior lumbar fusion procedures. The two-piece interbody cage design consists of a PEEK outer shell that expands in width, height, and lordosis with the insertion of a titanium shim. Once expanded, the open architecture design allows for ample graft delivery into the disc space. AREAS COVERED: The design and unique features of the FlareHawk family of expandable fusion cages are described. The indications for their use are discussed. Early clinical and radiographic outcome studies using the FlareHawk Interbody Fusion System are reviewed, and properties of competitor products are outlined. EXPERT OPINION: The FlareHawk multi-planar expandable interbody fusion cage is unique amongst the many lumbar fusion cages currently on the market. The multi-planar expansion, open architecture, and adaptive geometry set it apart from its competitors.

Preservation of Motion in Spine Surgery.

The number of spinal procedures and spinal fusions continues to grow. Although fusion procedures have a high success rate, they have inherent risks such as pseudarthrosis and adjacent segment disease. New innovations in spine techniques have sought to eliminate these complications by preserving motion in the spinal column. Several techniques and devices have been developed in the cervical and lumbar spine including cervical laminoplasty, cervical disk ADA, posterior lumbar motion preservation devices, and lumbar disk ADA. In this review, advantages and disadvantages of each technique will be discussed.

Learning curve for endoscopic posterior cervical foraminotomy.

PURPOSE: While anterior cervical discectomy and fusion as well as cervical disk arthroplasty are gold standard treatments for the surgical treatment of cervical radiculopathy, posterior endoscopic cervical foraminotomy (PECF) as a substitute procedure is gaining popularity. To date, studies investigating the number of surgeries needed to achieve proficiency in this procedure are lacking. The purpose of the study is to examine the learning curve for PECF. METHODS: The learning curve in operative time for two fellowship-trained spine surgeons at independent institutions was retrospectively assessed for 90 uniportal PECF procedures (PBD: n = 26, CPH: n = 64) performed from 2015 to 2022. Operative time was assessed across consecutive cases using a nonparametric monotone regression, and a plateau in operative time was used as a proxy to define the learning curve. Secondary outcomes assessing achievement of endoscopic prowess before and after the initial learning curve included number of fluoroscopy images, visual analog scale (VAS) for neck and arm, Neck Disability Index (NDI), and the need for reoperation. RESULTS: There was no significant difference in operative time between surgeons (p = 0.420). The start of a plateau for Surgeon 1 occurred at 9 cases and 111.6 min. The start of a plateau for Surgeon 2 occurred at 29 cases and 114.7 min. A second plateau for Surgeon 2 occurred at 49 cases and 91.8 min. Fluoroscopy use did not significantly change before and after surmounting the learning curve. The majority of patients achieved minimally clinically important differences in VAS and NDI after PECF, but postoperative VAS and NDI did not significantly differ before and after achieving the learning curve. There were no significant differences in revisions or postoperative cervical injections before and after reaching a steady state in the learning curve. CONCLUSION: PECF is an advanced endoscopic technique with an initial improvement in operative time that occurred after as few as 8 cases to as many as 28 cases in this series. A second learning curve may occur with additional cases. Patient-reported outcomes improve following surgery, and these outcomes are independent of the surgeon's position on the learning curve. Fluoroscopy use does not change significantly along the learning curve. PECF is a safe and effective technique that current and future spine surgeons should consider as part of their armamentarium.

Cervical Disk Arthroplasty and Range of Motion at 7 Years: Impact on Adjacent Level Degeneration.

STUDY DESIGN: Secondary analysis of data collected in a prospective, randomized, noninferiority Food and Drug Administration (FDA) Investigational Device Exemption (IDE) clinical trial. OBJECTIVE: The objective of this study was to evaluate the impact of range of motion (ROM) following single-level cervical disk arthroplasty (CDA) on the development of radiographic adjacent level degeneration (ALD). SUMMARY OF BACKGROUND DATA: The rationale for CDA is that maintenance of index-level ROM will decrease adjacent level stresses and ultimately reduce the development of ALD compared with anterior cervical discectomy and fusion. However, little information is available on the impact of hypermobility on the development of ALD after CDA. MATERIALS AND METHODS: Radiographic assessments were evaluated for index-level flexion-extension ROM and ALD. Continuous data was assessed using 1-way analysis of variance. The relationship between ALD progression and ROM was evaluated using χ 2 tests. The α was set at 0.05. RESULTS: More ALD progression was observed after anterior cervical discectomy and fusion than CDA ( P =0.002 at the superior and P =0.049 at the inferior level). Furthermore, there was an association between ALD progression and ROM ( P =0.014 at the superior level and P =0.050 at the inferior level) where patients with mid-ROM after CDA experienced the lowest frequency of ALD progression at the superior and inferior levels. Patients with the lowest and highest ROM after CDA experienced a greater increase in ALD score at the inferior level ( P =0.046). Sex and age were associated with ROM groups ( P =0.001 and 0.023, respectively). CONCLUSIONS: While maintenance of index-level ROM is protective after CDA, patients with the highest ROM after CDA have similar rates of ALD progression to the lowest ROM and greater increases in ALD compared with mid-ROM after CDA. High ROM after CDA may contribute to ALD progression.

Review of Prospective Trials for Degenerative Cervical Myelopathy.

Degenerative cervical myelopathy (DCM) is the leading cause of spinal cord dysfunction in adults. DCM refers to a collection of degenerative conditions that cause the narrowing of the cervical canal resulting in neurological dysfunction. A lack of high-quality studies and a recent increase in public health awareness has led to numerous prospective studies evaluating DCM. Studies evaluating the efficacy of surgical intervention for DCM can be characterized by the presence (comparative) or absence (noncomparative) of a nonoperative control group. Noncomparative studies predominate due to concerns regarding treatment equipoise. Comparative studies have been limited by methodological issues and have not produced consistent findings. More recent noncomparative studies have established the safety and efficacy of surgical intervention for DCM, including mild myelopathy. The optimal surgical intervention for DCM remains controversial. A recent randomized clinical trial comparing dorsal and ventral techniques found similar improvements in patient-reported physical function at early follow-up. Recent prospective studies have enriched our understanding of DCM and helped guide current treatment recommendations.

Prediction of Admission Costs Following Anterior Cervical Discectomy and Fusion Utilizing Machine Learning.

STUDY DESIGN: Retrospective case series. OBJECTIVE: Predict cost following anterior cervical discectomy and fusion (ACDF) within the 90-day global period using machine learning models. BACKGROUND: The incidence of ACDF has been increasing with a disproportionate decrease in reimbursement. As bundled payment models become common, it is imperative to identify factors that impact the cost of care. MATERIALS AND METHODS: The Nationwide Readmissions Database (NRD) was accessed in 2018 for all primary ACDFs by the International Classification of Diseases 10th Revision (ICD-10) procedure codes. Costs were calculated by utilizing the total hospital charge and each hospital's cost-to-charge ratio. Hospital characteristics, such as volume of procedures performed and wage index, were also queried. Readmissions within 90 days were identified, and cost of readmissions was added to the total admission cost to represent the 90-day healthcare cost. Machine learning algorithms were used to predict patients with 90-day admission costs >1 SD from the mean. RESULTS: There were 42,485 procedures included in this investigation with an average age of 57.7±12.3 years with 50.6% males. The average cost of the operative admission was $24,874±25,610, the average cost of readmission was $25,371±11,476, and the average total cost was $26,977±28,947 including readmissions costs. There were 10,624 patients who were categorized as high cost. Wage index, hospital volume, age, and diagnosis-related group severity were most correlated with the total cost of care. Gradient boosting trees algorithm was most predictive of the total cost of care (area under the curve=0.86). CONCLUSIONS: Bundled payment models utilize wage index and diagnosis-related groups to determine reimbursement of ACDF. However, machine learning algorithms identified additional variables, such as hospital volume, readmission, and patient age, that are also important for determining the cost of care. Machine learning can improve cost-effectiveness and reduce the financial burden placed upon physicians and hospitals by implementing patient-specific reimbursement.

Allograft Versus Autograft in Anterior Cervical Discectomy and Fusion: A Propensity-Matched Analysis.

Objective To compare the 30-day complication rate associated with allograft versus autograft in anterior cervical discectomy and fusion (ACDF) and to determine preoperative factors that may influence complication rate. Methods The American College of Surgeons National Surgical Quality Improvement Program database was retrospectively queried from 2014 to 2017 for all procedures with CPT codes for ACDF (22551). Patients undergoing ACDF with either autograft or allograft were matched by propensity scores based on age, sex, body mass index, and comorbidities. The incidence of adverse events in the 30-day postoperative period was compared. Results A total of 21,588 patients met the inclusion and exclusion criteria. Following the 10:1 propensity match, 17,061 remained in the study (1,551 autograft and 15,510 allograft). The overall adverse event rate was 3.18%; 3.48% for autograft and 3.15% for allograft (P=0.494). Autograft had a significantly greater incidence of extended length of stay (>2 d) (LOS) (48.9% vs 34.8%; P<0.001). Multivariate analysis suggested that autograft selection was associated with extended LOS (OR 1.4; 95% CI 1.3-1.5). Conclusion The results of this study provide information regarding how graft selection can relate to extended hospital LOS and influence postoperative complications. Extended LOS may be associated with worse patient outcomes and increase the overall cost of care. Further study should be performed to determine which patients would benefit from autograft versus allograft with regards to long-term outcomes, in consideration of these increased short-term complications.

Appropriate Telemedicine Utilization in Spine Surgery: Results From a Delphi Study.

STUDY DESIGN: Delphi expert panel consensus. OBJECTIVE: To obtain expert consensus on best practices for appropriate telemedicine utilization in spine surgery. SUMMARY OF BACKGROUND DATA: Several studies have shown high patient satisfaction associated with telemedicine during the COVID-19 peak pandemic period as well as after easing of restrictions. As this technology will most likely continue to be employed, there is a need to define appropriate utilization. METHODS: An expert panel consisting of 27 spine surgeons from various countries was assembled in February 2021. A two-round consensus-based Delphi method was used to generate consensus statements on various aspects of telemedicine (separated as video visits or audio visits) including themes, such as patient location and impact of patient diagnosis, on assessment of new patients. Topics with ≥75% agreement were categorized as having achieved a consensus. RESULTS: The expert panel reviewed a total of 59 statements. Of these, 32 achieved consensus. The panel had consensus that video visits could be utilized regardless of patient location and that video visits are appropriate for evaluating as well as indicating for surgery multiple common spine pathologies, such as lumbar stenosis, lumbar radiculopathy, and cervical radiculopathy. Finally, the panel had consensus that video visits could be appropriate for a variety of visit types including early, midterm, longer term postoperative follow-up, follow-up for imaging review, and follow-up after an intervention (i.e., physical therapy, injection). CONCLUSION: Although telemedicine was initially introduced out of necessity, this technology most likely will remain due to evidence of high patient satisfaction and significant cost savings. This study was able to provide a framework for appropriate telemedicine utilization in spine surgery from a panel of experts. However, several questions remain for future research, such as whether or not an in-person consultation is necessary prior to surgery and which physical exam maneuvers are appropriate for telemedicine.Level of Evidence: 4.

Spine Patient Satisfaction With Telemedicine During the COVID-19 Pandemic: A Cross-Sectional Study.

STUDY DESIGN: Original research, cross-sectional study. OBJECTIVES: Evaluate patient satisfaction with spine care delivered via telemedicine. Identify patient- and visit-based factors associated with increased satisfaction and visit preference. METHODS: Telemedicine visits with a spine surgeon at 2 practices in the United States between March and May 2020 were eligible for inclusion in the study. Patients were sent an electronic survey recording overall satisfaction, technical or clinical issues encountered, and preference for a telemedicine versus an in-person visit. Factors associated with poor satisfaction and preference of telemedicine over an in-person visit were identified using multivariate logistic regression. RESULTS: A total of 772 responses were collected. Overall, 87.7% of patients were satisfied with their telemedicine visit and 45% indicated a preference for a telemedicine visit over an in-person visit if given the option. Patients with technical or clinical issues were significantly less likely to achieve 5 out of 5 satisfaction scores and were significantly more likely to prefer an in-person visit. Patients who live less than 5 miles from their surgeon's office and patients older than 60 years were also significantly more likely to prefer in-person visits. CONCLUSIONS: Spine telemedicine visits during the COVID-19 pandemic were associated with high patient satisfaction. Additionally, 45% of respondents indicated a preference for telemedicine versus an in-patient visit in the future. In light of these findings, telemedicine for spine care may be a preferable option for a subset of patients into the future.

Predictors of long-term clinical outcomes in adult patients after lumbar total disc replacement: development and validation of a prediction model.

OBJECTIVE: Long-term outcomes of single-level lumbar arthroplasty are understood to be very good, with the most recent Investigational Device Exemption (IDE) trial showing a < 5% reoperation rate at the close of the 7-year study. This post hoc analysis was conducted to determine whether specific patients from the activL IDE data set had better outcomes than the mean good outcome of the IDE trial, as well as to identify contributing factors that could be optimized in real-world use. METHODS: Univariable and multivariable logistic regression models were developed using the randomized patient set (n = 283) from the activL trial and used to identify predictive factors and to derive risk equations. The models were internally validated using the randomized patient set and externally validated using the nonrandomized patient set (n = 52) from the activL trial. Predictive power was assessed using area under the receiver operating characteristic curve analysis. RESULTS: Two factors were significantly associated with achievement of better than the mean outcomes at 7 years. Randomization to receive the activL device was positively associated with better than the mean visual analog scale (VAS)-back pain and Oswestry Disability Index (ODI) scores, whereas preoperative narcotics use was negatively associated with better than the mean ODI score. Preoperative narcotics use was also negatively associated with return to unrestricted full-time work. Other preoperative factors associated with positive outcomes included unrestricted full-time work, working manual labor after index back injury, and decreasing disc height. Older age, greater VAS-leg pain score, greater ODI score, female sex, and working manual labor before back injury were identified as preoperative factors associated with negative outcomes. Preoperative BMI, VAS-back pain score, back pain duration ≥ 1 year, SF-36 physical component summary score, and recreational activity had no effect on outcomes. CONCLUSIONS: Lumbar total disc replacement for symptomatic single-level lumbar degenerative disc disease is a well-established option for improving long-term patient outcomes. Discontinuing narcotics use may further improve patient outcomes, as this analysis identified associations between no preoperative narcotics use and better ODI score relative to the mean score of the activL trial at 7 years and increased likelihood of return to work within 7 years. Other preoperative factors that may further improve outcomes included unrestricted full-time work, working manual labor despite back injury, sedentary work status before back injury, and randomization to receive the activL device. Tailoring patient care before total disc replacement may further improve patient outcomes.

Final Long-Term Reporting from a Randomized Controlled IDE Trial for Lumbar Artificial Discs in Single-Level Degenerative Disc Disease: 7-Year Results.

BACKGROUND: This study compared 7-year safety and efficacy outcomes of activL and ProDisc-L lumbar total disc replacements in patients with symptomatic, single-level lumbar degenerative disc disease (DDD). The objectives are to report 7-year outcomes of the trial, evaluate the outcomes for patients lost to follow-up, and determine whether early outcomes predict long-term outcomes. METHODS: This was a prospective, multicenter, randomized, controlled investigational device exemption study. Eligible patients with symptomatic, single-level lumbar DDD had failed ≥6 months of nonsurgical management. Patients (N = 283) were randomized to receive activL (n = 218) or ProDisc-L (n = 65). At 7 years, data were available from 206 patients (activL, 160; ProDisc-L, 46). Logistic regression models were fit to predict 7-year outcomes for patients lost to follow-up after 2 years. RESULTS: At 7 years, the activL group was noninferior to the ProDisc-L group on the primary composite endpoint (P = .0369). Both groups showed significant reductions in back/leg pain severity and improvements in disability index and quality-of-life relative to baseline (P < .0001). In both groups, opioid use was significantly reduced at 7 years (0%) relative to baseline (P < .01), and the overall reoperation rates were low (4.6%). activL patients showed a significantly better range of motion (ROM) for flexion-extension rotation than ProDisc-L patients (P = .0334). A significantly higher proportion of activL patients did not report serious adverse events (activL, 62%; ProDisc-L, 43%; P = .011). Predictive modeling indicated that >70% of patients (depending on outcome) lost to follow-up after 2 years would show clinically significant improvement at 7 years if improvements were achieved at 2 years. CONCLUSIONS: The benefits of activL and ProDisc-L are maintained after 7 years, with significant improvements from baseline observed in pain, function, and opioid use. activL is more effective at preserving ROM than ProDisc-L and has a more favorable safety profile. Improvements in other primary and secondary outcomes were similar between both disc designs. LEVEL OF EVIDENCE: 1.

Assessing the cone of economy in patients with spinal disease using only a force plate: an observational retrospective cohort study.

STUDY DESIGN: This is a retrospective cohort with multiple regression modeling. OBJECTIVE: The aim is to develop a new method for estimating cone of economy (CoE) using a force plate rather than traditional motion capture. BACKGROUND: Currently, most spinal deformity surgeons rely on static radiographic parameters for alignment, balance, and outcomes data alongside patient-reported outcome measures. The CoE, the stable region of upright posture, can be objectively measured to determine the efficiency and balance of the spine. Motion capture technology is currently used to collect data to calculate CoE, but this requires expensive and complex equipment, which is a barrier to widespread adoption and clinical use of CoE measurements. Force plates, which measure pressure, are less expensive and can be used in a clinical setting. METHODS: Motion capture and a force plate were used to quantify the CoE of 473 subjects (423 spinal surgical candidates; 50 healthy controls; 271 females; age: 58.60 ± 15.27; height: 1.69 ± 0.13; weight: 81.07 ± 20.91), and a linear multiple regression model was used to predict CoE using force plate data in a human motion laboratory setting. Patients were required to stand erect with feet together and eyes open in their self-perceived balanced and natural position for a full minute while measures of sway and center of pressure (CoP) were recorded. RESULTS: The CoP variable regression model successfully predicted CoE measurements. The variables that were used to predict vertical CoE were CoP coronal sway, CoP sagittal sway, and CoP total sway in several combinations. The coefficient of determination for the head total sway model indicated a 87.0% correlation (F(3,469) = 1044.14, p < 0.001). The coefficient of determination for the head sagittal sway model indicated a 69.2% correlation (F(3,469) = 351.70, p < 0.001). The coefficient of determination for the head coronal sway model indicated a 85.2% correlation (F(3,469) = 899.27, p < 0001). CONCLUSION: Cone of economy was estimated from force plate data using center of pressure with high correlation without the use of motion capture in healthy controls and a variety of spine patients. This could lower the entry burden for measurement of the CoE in patients, enabling widespread use. This would provide surgeons objective global balance data, along with Haddas' CoE classification system, that could assist with surgical decision-making and facilitate objective monitoring surgical outcomes.

Validity of a pre-surgical algorithm to predict pain, functional disability, and emotional functioning 1 year after spine surgery.

Psychopathology has been associated with patient reports of poor outcome and an algorithm has been useful in predicting short-term outcomes. The objective of this study is to investigate whether a pre-surgical psychological algorithm could predict 1-year spine surgery outcome reports, including pain, functional disability, and emotional functioning. A total of 1,099 patients consented to participate. All patients underwent spine surgery (e.g., spinal fusion, discectomy, etc.). Pre-operatively, patients completed self-report measures prior to surgery. An algorithm predicting patient prognosis based on data from the pre-surgical psychological evaluation was filled out by the provider for each patient prior to surgery. Post-operatively, patients completed self-report measures at 3- and 12-months after surgery. Longitudinal latent class growth analysis (LCGA) was used to derive patient outcome groups. These outcome groups were then compared to pre-surgical predictions made. LCGA analyses derived three groups of patients from the reported outcome data (entropy = .84): excellent outcomes, good outcomes, and poor outcomes. The excellent and good groups demonstrated improvements over time, but the poor outcome groups, on some measures, reported worsening of pain, functional disability, and emotional functioning over time. The pre-surgical algorithm yielded good concordance with the statistically derived outcome groups (Kendall's W = .81). Using a pre-surgical psychological evaluation algorithm for predicting long-term spine surgery outcomes can identify patients who are unlikely to report good outcomes, and point to areas for psychological intervention that can either improve surgery results or to be utilized as alternatives to elective spine surgery. (PsycInfo Database Record (c) 2021 APA, all rights reserved).