Trends in Indications and Contraindications for Cervical Disk Arthroplasty from 2009 to 2019.

STUDY DESIGN: Cross-sectional study. OBJECTIVE: Assess trends of indications and contraindications for the use of Cervical Disk Arthroplasty (CDA). SUMMARY OF BACKGROUND DATA: As spine surgeons become more familiar with CDA, there have been expansions in indications. METHODS: The Medicare Provider Analysis and Review Limited Data Sets for 2009, 2014, and 2019 were utilized. Patients undergoing elective CDA were included. Diagnosis for index surgery and "contraindications" as defined by original CDA Investigative Device Exemption (IDE) criteria were assessed. Variables were identified by the International Classification of Diseases (ICD)-9 or ICD-10 diagnosis and procedural codes. RESULTS: A total of 1067 elective CDA patients were included. There were 230 patients in 2009, 300 patients in 2014, and 537 patients in 2019. The proportion of patients aged >65 increased from 35% to 51% (P<0.001). Incidence of CDA for radiculopathy increased from 57% to 69% (P<0.001), myelopathy increased from 23% to 78% (P<0.001), and spondylosis without radiculopathy or myelopathy decreased from 19% to 3% (P<0.001). There were increased incidences of ankylosing spondylitis (0.4% to 2.8%, P=0.007), long-term steroid use (1% to 2%, P=0.039), morbid obesity (2% to 6%, P=0.019), and osteoporosis (1% to 5%, P=0.014). The incidence of hybrid CDA and anterior cervical discectomy and fusion (ACDF) decreased from 28% to 23% (P=0.007). CONCLUSION: From 2009 to 2019, the number of CDA performed in older patients increased. An increase in the use of CDA for the treatment of myelopathy and radiculopathy and a decrease in the treatment of isolated cervical spondylosis was observed. The proportion of CDA performed in patients with original IDE trial "contraindications" increased. Further research into the efficacy of CDA for patients with contraindications is warranted.

Resource Utilization following Anterior Versus Posterior Cervical Decompression and Fusion for Acute Central Cord Syndrome.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The purpose of this study is to compare the impact of anterior cervical decompression and fusion (ACDF) versus posterior cervical decompression and fusion (PCDF) for the treatment of acute traumatic central cord syndrome (CCS) on hospital episodes of care in terms of (1) cost, (2) length of hospital stay, and (3) discharge destination. SUMMARY OF BACKGROUND DATA: Acute traumatic CCS is the most common form of spinal cord injury in the United States. CCS is commonly treated with surgical decompression and fusion. Hospital resource utilization based on surgical approach remains unclear. METHODS: Patients undergoing ACDF and PCDF for acute traumatic CCS were identified using the 2019 Medicare Provider Analysis and Review Limited Data Set and Centers for Medicare and Medicaid Services 2019 Impact File. Multivariate models for hospital cost of care, length of stay, and discharge destination were performed, controlling for confounders. Subanalysis of accommodation and revenue center cost drivers was performed. RESULTS: There were 1474 cases that met inclusion criteria: 673 ACDF (45.7%) and 801 PCDF (54.3%). ACDF was independently associated with a decreased cost of $9802 (P<0.001) and a 59.2% decreased risk of discharge to nonhome destinations (adjusted odds ratio: 0.408, P<0.001). The difference in length of stay was not statistically significant. On subanalysis of cost drivers, ACDF was associated with decreased charges ($55,736, P<0.001) compared with PCDF, the largest drivers being the intensive care unit ($15,873, 28% of total charges, P<0.001) and medical/surgical supply charges ($19,651, 35% of total charges, P<0.001). CONCLUSIONS: For treatment of acute traumatic CCS, ACDF was associated with almost $10,000 less expensive cost of care and a 60% decreased risk of discharge to nonhome destination compared with PCDF. The largest cost drivers appear to be ICU and medical/surgical-related. These findings may inform value-based decisions regarding the treatment of acute traumatic CCS. However, injury and patient clinical factors should always be prioritized in surgical decision-making, and increased granularity in reimbursement policies is needed to prevent financial disincentives in the treatment of patients with CCS better addressed with posterior approach-surgery.

Left-digit bias in surgical decision-making for lumbar spinal stenosis.

BACKGROUND CONTEXT: Left-digit bias is a behavioral heuristic or cognitive "shortcut" in which the leftmost digit of a number, such as patient age, disproportionately influences surgical decisions. PURPOSE: To determine if left-digit bias in patient age influences the decision to perform arthrodesis with instrumentation vs decompression in lumbar spinal stenosis (LSS). DESIGN: Retrospective cohort. PATIENT SAMPLE: Patients with an ICD-10 diagnosis of lumbar stenosis or spondylolisthesis identified in the 2017-2021 National Surgical Quality Improvement Program (NSQIP) database. OUTCOME MEASURES: The primary outcome was the percent of patients who underwent arthrodesis with instrumentation (AwI). Matched age group comparisons without left-digit differences (ie, 76/77 vs 78/79, 80/81 vs 82/83, etc.) were performed to isolate the effect of the heuristic. Secondary outcomes including peri-operative events and complications were also compared within AwI and decompression cohorts. METHODS: Using CPT codes, procedures were classified as either AwI or decompression. Patients were grouped into 6 cohorts based on 2-year age windows (74/75, 76/77, 78/79, 80/81, 82/83, 84/85). The cohorts were propensity matched with neighboring age groups based on the presence of spondylolisthesis, demographics, and comorbidities. The primary comparison was between those aged 78/79 vs 80/81. RESULTS: After matching, the primary cohort consisted of two groups of 1,550 patients (aged 78/79 and 80/81). Patients aged 80/81 were less likely to undergo AwI than patients aged 78/79 (23.5% vs 27.2%, p=.021). AwI procedures occurred at similar rates between age groups with the same left digit. Within the decompression and AwI cohorts, there were no differences in secondary outcomes between patients aged 78/79 and 80/81. CONCLUSIONS: LSS patients aged 80/81 are less likely to undergo AwI than patients aged 78/79, regardless of comorbidities. This was not seen when comparing patients with similar left digits in age. Until objective measures of physiologic capacity are established, left-digit bias may influence clinical decisions.

Elective Single-Level Primary Anterior Cervical Decompression and Fusion for Degenerative Spondylotic Cervical Myelopathy is Associated With Decreased Resource Utilization Versus Posterior Cervical Decompression and Fusion.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To compare elective single-level anterior cervical discectomy and fusion (ACDF) versus posterior cervical decompression and fusion (PCDF) for degenerative cervical myelopathy (DCM) in terms of (1) cost, (2) length of hospital stay, and (3) discharge destination in Medicare patients. A sub-analysis of potential cost drivers was also performed. BACKGROUND: In the era of value-based medicine, there is substantial interest in reducing the cost of care. Both ACDF and PCDF are used to treat DCM but carry different morbidity and risk profiles that can impact hospital resource utilization. However, this has not been assessed on a national level. METHODS: Patients undergoing single-level elective ACDF and PCDF surgery were identified using the 2019 Medicare Provider Analysis and Review (MedPAR) Limited Data Set (LDS) and Centers for Medicare and Medicaid Services (CMS) 2019 Impact File. Multivariate models of hospital cost of care, length of stay, and discharge destination were performed, controlling for confounders. A univariate sub-analysis of 9 revenue centers was performed. RESULTS: In all, 3942 patients met the inclusion criteria. The mean cost of elective single-level cervical fusion for myelopathy was $18,084±10,783, and the mean length of stay was 2.45±2.95 d. On multivariate analysis, ACDF was independently associated with decreased cost of $5,814 (P<0.001), shorter length of stay by 1.1 days (P<0.001), and decreased risk of nonhome discharge destination by 58% (adjusted odds ratio: 0.422, P<0.001).On sub-analysis of 9 revenue centers, medical/surgical supply ($10,497, 44%), operating room charges ($5401, 23%), and accommodations ($3999, 17%) were the largest drivers of charge differences. CONCLUSIONS: Single-level elective primary ACDF for DCM was independently associated with decreased cost, decreased hospital length of stay, and a lower rate of nonhome discharge compared with PCDF. Medical and surgical supply, operating room, and accommodation differences between ACDF and PCDF are potential areas for intervention. Increased granularity in reimbursement structures is warranted to prevent the creation of disincentives to the treatment of patients with DCM with pathology that is better addressed with PCDF. LEVEL OF EVIDENCE: Level-III Retrospective Cohort Study.

Telemedicine in Spine Patients: Utilization and Satisfaction Remain High Even After Easing of COVID-19 Lockdown Restrictions.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The objectives of the present study were to (1) define telemedicine utilization rates during and after the initial height of the COVID-19 lockdown period and (2) determine patient satisfaction with telemedicine during and after the initial height of the COVID-19 lockdown period for spine patients at an orthopedic specialty hospital. SUMMARY OF BACKGROUND DATA: Previous studies have shown high patient satisfaction with telemedicine during the initial height of the COVID-19 pandemic. However, there exists limited data about spine telemedicine utilization and patient satisfaction after the reopening of in-person office visits and the easing of restrictions on elective surgical care. MATERIALS AND METHODS: All patients who had an in-person or telemedicine visit at an urban tertiary specialty hospital from April 1, 2020 to April 15, 2021 were identified. Rates of overall telemedicine utilization over time were delineated. Patient satisfaction with telemedicine, as assessed through a series of questionnaires, was also evaluated over time. RESULTS: Overall, 60,368 patients were identified. Of these, 19,568 patients (32.4%) had telemedicine visit. During the peak initial coronavirus lockdown period, the rate of overall telemedicine utilization, on average, was greater than 90%. After the peak period, the rate of overall telemedicine utilization on average was at ~29% of all visits per month. The percentage of patients who would have been definitely comfortable if the telemedicine visit had been in-person increased over the entire study period ( P <0.001). Despite this, patient satisfaction based on survey responses remained statistically similar throughout the study period ( P >0.05). CONCLUSION: The rate of telemedicine utilization in spine patients remains high, at ~one-third of all visits, even after the initial peak coronavirus lockdown period. In addition, patient satisfaction with telemedicine remained consistent throughout the study period, regardless of pandemic restrictions on in-person visits. LEVEL OF EVIDENCE: 3.

Floor-Mounted Robotic Pedicle Screw Placement in Lumbar Spine Surgery: An Analysis of 1,050 Screws.

OBJECTIVE: To analyze the usage of floor-mounted robot in minimally invasive lumbar fusion. METHODS: Patients who underwent minimally invasive lumbar fusion for degenerative pathology using floor-mounted robot (ExcelsiusGPS) were included. Pedicle screw accuracy, proximal level violation rate, pedicle screw size, screw-related complications, and robot abandonment rate were analyzed. RESULTS: Two hundred twenty-nine patients were included. Most surgeries were primary single-level fusion. Sixty-five percent of surgeries had intraoperative computed tomography (CT) workflow, 35% had preoperative CT workflow. Sixty-six percent were transforaminal lumbar interbody fusion, 16% were lateral, 8% were anterior, and 10% were a combined approach. A total of 1,050 screws were placed with robotic assistance (85% in prone position, 15% in lateral position). Postoperative CT scan was available for 80 patients (419 screws). Overall pedicle screw accuracy rate was 96.4% (prone, 96.7%; lateral, 94.2%; primary, 96.7%; revision, 95.3%). Overall poor screw placement rate was 2.8% (prone, 2.7%; lateral, 3.8%; primary, 2.7%; revision, 3.5%). Overall proximal facet and endplate violation rates were 0.4% and 0.9%. Average diameter and length of pedicle screws were 7.1 mm and 47.7 mm. Screw revision had to be done for 1 screw (0.1%). Use of the robot had to be aborted in 2 cases (0.8%). CONCLUSION: Usage of floor-mounted robotics for the placement of lumbar pedicle screws leads to excellent accuracy, large screw size, and negligible screw-related complications. It does so for screw placement in prone/lateral position and primary/revision surgery alike with negligible robot abandonment rates.

Trends in costs, reimbursements, and surgeon payments for cervical disc arthroplasty cost of care from 2009 to 2019.

OBJECTIVE: The use of cervical disc arthroplasty (CDA) continues to increase in the Medicare population. As healthcare costs continue to rise, payors have begun to implement bundled payment structures for spine surgery. While Medicare has steadily decreased reimbursements for cervical fusions, Medicare reimbursements for CDA have not been studied. The purpose of this study was to assess trends in 1) hospital costs and reimbursement, 2) physician reimbursement, and 3) potential cost drivers for CDA in a Medicare population. METHODS: This is a retrospective longitudinal study of CDA in Medicare patients. The Medicare Provider Analysis and Review Limited Data Sets for 2009, 2014, and 2019 were used for this study. Patients undergoing elective CDA were included. Corresponding Inpatient Prospective Payment System files were used to calculate cost through cost-to-charge ratios. Physician fees were obtained from the Medicare Physician Fee Schedule Look-Up Tool. All financial data were adjusted for inflation to 2019 values based on the Consumer Price Index for All Urban Consumers. Demographic, comorbidity, surgical, and hospital trends were assessed. Trends in revenue center-level charges were also assessed. RESULTS: Adjusted for inflation, from 2009 to 2019, mean total hospital charges for elective CDA increased from $64,609 ± $45,787 to $111,874 ± $78,611 (73% increase, p < 0.001) and the mean total cost for index hospital admission increased from $19,665 ± $13,414 to $24,682 ± $13,818 (26% increase, p < 0.001). Over the same period, Medicare reimbursement increased from a mean of $11,154 ± $11,684 to $12,879 ± $13,613 (15% increase, p = 0.003), while total reimbursement increased from a mean of $15,005 ± $15,684 to $15,547 ± $15,829 (4% increase, p = 0.040). The mean hospital profit decreased from -$4076 ± $14,041 to -$9023 ± $16,084 (-121%, p < 0.001). Surgeon reimbursement for CDA decreased from a mean of $1850 ± $165 (2009) to $1722 ± $138 (2019) (7% decrease, p < 0.001). On multivariate analysis, increasing year of surgery (p < 0.001), increasing age (p = 0.001), increasing length of stay (p < 0.001), rural hospital setting (p = 0.027), and hospital geography (p < 0.001) were independently associated with cost of care. Medical/surgical supplies and operating room charges increased 71.6% (p < 0.001) and 98.5% (p < 0.001) and accounted for 41.1%-42.5% and 30.6%-35.1% of total charges, respectively. CONCLUSIONS: From 2009 to 2019, costs of care for elective inpatient CDA increased disproportionately to reimbursement. Hospitals operated at increasing losses and surgeon reimbursement decreased. Cost of care was independently associated with year of surgery, increasing age, length of stay, hospital setting, and hospital geography. The main charge drivers were medical/surgical supplies and operating room charges. These results may have implications for the future financial feasibility of inpatient CDA for Medicare patients and targets to improve the value of CDA. Further study is necessary to provide fair reimbursement for CDA in Medicare patients and prevent financially based bias against use of CDA in Medicare patients.

Location of the Femoral Nerve in the Lateral Decubitus Versus Prone Position.

STUDY DESIGN: Cadaveric study. OBJECTIVE: To compare the position of the femoral nerve within the lumbar plexus at the L4-L5 disc space in the lateral decubitus vs prone position. METHODS: Seven lumbar plexus specimens were dissected and the femoral nerve within the psoas muscle was identified and marked with radiopaque paint. Lateral fluoroscopic images of the cadaveric specimens in the lateral decubitus vs prone position were obtained. The location of the radiopaque femoral nerve at the L4-L5 disc space was normalized as a percentage of the L5 vertebral body (0% indicates posterior location and 100% indicates anterior location at the L4-L5 disc space). The location of the femoral nerve at L4-L5 in the lateral decubitus vs prone position was compared using a paired t test. RESULTS: In the lateral decubitus position, the femoral nerve was located 28% anteriorly from the posterior edge of the L4-L5 disc space, and in the prone position, the femoral nerve was relatively more posterior, located 18% from the posterior edge of the L4-L5 disc space (P = .037). CONCLUSIONS: The femoral nerve was on average more posteriorly located at the L4-L5 disc space in the prone position compared to lateral decubitus. This more posterior location allows for a larger safe zone at the L4-L5 disc space, which may decrease the incidence of neurologic complications associated with Lateral lumbar interbody fusion in the prone vs lateral decubitus position; however, further studies are needed to evaluate this possible clinical correlation.

Complications and Revisions After Spine Surgery in Patients With Skeletal Dysplasia: Have We Improved?

STUDY DESIGN: Retrospective case series. OBJECTIVE: To report contemporary rates of complications and subsequent surgery after spinal surgery in patients with skeletal dysplasia. METHODS: A case series of 25 consecutive patients who underwent spinal surgery between 2007 and 2017 were identified from a single institution's skeletal dysplasia registry. Patient demographics, medical history, surgical indication, complications, and subsequent surgeries (revisions, extension to adjacent levels, or for pathology at a non-contiguous level) were collected. Charlson comorbidity indices were calculated as a composite measure of overall health. RESULTS: Achondroplasia was the most common skeletal dysplasia (76%) followed by spondyloepiphyseal dysplasia (20%); 1 patient had diastrophic dysplasia (4%). Average patient age was 53.2 ± 14.7 years and most patients were in excellent cardiovascular health (88% Charlson Comorbidity Index 0-4). Mean follow up after the index procedure was 57.4 ± 39.2 months (range). Indications for surgery were mostly for neurologic symptoms. The most commonly performed surgery was a multilevel thoracolumbar decompression without fusion (57%). Complications included durotomy (36%), neurologic complication (12%), and infection requiring irrigation and debridement (8%). Nine patients (36%) underwent a subsequent surgery. Three patients (12%) underwent a procedure at a non-contiguous anatomic zone, 3 (12%) underwent a revision of the previous surgery, and another 3 (12%) required extension of their previous decompression or fusion. CONCLUSIONS: Surgical complication rates remain high after spine surgery in patients with skeletal dysplasia, likely attributable to inherent characteristics of the disease. Patients should be counseled on their risk for complication and subsequent surgery.

Robotic-Assisted Single-Position Prone Lateral Lumbar Interbody Fusion: Indications, Techniques, and Outcomes.

Background: Lateral lumbar interbody fusion (LLIF) is a widely utilized minimally invasive surgical procedure for anterior fusion of the lumbar spine. However, posterior decompression or instrumentation often necessitates patient repositioning, which is associated with increased operative time and time under anesthesia1-3. The single-position prone transpsoas approach is a technique that allows surgeons to access both the anterior and posterior aspects of the spine, bypassing the need for intraoperative repositioning and therefore optimizing efficiency4. The use of robotic assistance allows for decreased radiation exposure and increased accuracy, both with placing instrumentation and navigating the lateral corridor. Description: The patient is placed in the prone position, and pedicle screws are placed prior to interbody fusion. Pedicle screws are placed with robotic guidance. After posterior instrumentation, a skin incision for LLIF is made in the cephalocaudal direction, orthogonal to the disc space, with use of intraoperative (robotic) navigation. Fascia and abdominal muscles are incised to enter the retroperitoneal space. Under direct visualization, dilators are placed through the psoas muscle into the disc space, and an expandable retractor is placed and maintained with use of the robotic arm. Following a thorough discectomy, the disc space is sized with trial implants. The expandable cage is placed, and intraoperative fluoroscopy is utilized to verify good instrumentation positioning. Finally, posterior rods are placed percutaneously. Alternatives: An alternative surgical approach is a traditional LLIF with the patient beginning in the lateral position, with intraoperative repositioning from the lateral to the prone position if circumferential fusion is warranted. Additional alternative surgical procedures include anterior or posterior lumbar interbody fusion techniques. Rationale: LLIF is associated with reported advantages of decreased risks of vascular injury, visceral injury, dural tear, and perioperative infection5,6. The single-position prone transpsoas approach confers the added benefits of reduced operative time, anesthesia time, and surgical staffing requirements7. Other potential benefits of the prone lateral approach include improved lumbar lordosis correction, gravity-induced displacement of peritoneal contents, and ease of posterior decompression and instrumentation8-11. Additionally, the use of robotic assistance offers numerous benefits to minimally invasive techniques, including intraoperative navigation, instrumentation templating, a more streamlined workflow, and increased accuracy in placing instrumentation, while also providing a reduction in radiation exposure and operative time. In our experience, the table-mounted LLIF retractor has a tendency to drift toward the floor-i.e., anteriorly-when the patient is positioned prone, which may, in theory, increase the risk of iatrogenic bowel injury. The rigid robotic arm is much stiffer than the traditional retractor, thereby reducing this risk. Expected Outcomes: Compared with traditional LLIF, with the patient in the lateral and then prone positions, the single-position prone LLIF has been shown to have several benefits. Guiroy et al. performed a systematic review comparing single and dual-position LLIF and found that the single-position surgical procedure was associated with significantly lower operative time (103.1 versus 306.6 minutes), estimated blood loss (97.3 versus 314.4 mL), and length of hospital stay (1.71 versus 4.08 days)17. Previous studies have reported improved control of segmental lordosis in the prone position, which may be advantageous for patients with sagittal imbalance18,19. Important Tips: Adequate release of the deep fascial layers is critical for minimizing deflection of retractors and navigated instruments.The hip should be maximally extended to maximize lordosis, allowing for posterior translation of the femoral nerve and increasing the width of the lateral corridor.A bolster is placed against the rib cage to provide resistance to the laterally directed force when impacting the graft.The cranial and caudal limits of the approach are bounded by the ribcage and iliac crest; thus, surgery at the upper or lower lumbar levels may not be feasible for this approach. Preoperative radiographs should be evaluated to determine the feasibility of this approach at the intended levels.When operating at the L4-L5 disc space, posterior retraction places substantial tension on the femoral nerve. Thus, retractor time should be minimized as much as possible and limited to a maximum of approximately 20 minutes20-22.A depth of field (distance from the midline to the flank) of approximately 20 cm may be the limit for this approach with the current length of retractor blades19.In robotic-assisted surgical procedures, minor position shifts in surface landmarks, the robotic arm, or the patient may substantially impact the navigation software. It is critical for the patient and navigation components to remain fixed throughout the operation.In addition to somatosensory evoked potential and electromyographic monitoring, additional motor evoked potential neuromonitoring or monitoring of the saphenous nerve may be considered22.In the prone position, the tendency is for the retractor to migrate superficially and anteriorly. It is critical to be aware of this tendency and to maintain stable retractor positioning. Acronyms and Abbreviations: LLIF = lateral lumbar interbody fusionMIS = minimally invasive surgeryPTP = prone transpsoasy.o. = years oldASIS = anterior superior iliac spinePSIS = posterior superior iliac spineALIF = anterior lumbar interbody fusionTLIF = transforaminal lumbar interbody fusionMEP = motor evoked potentialSSEP = somatosensory evoked potentialEMG = electromyographyCT = computed tomographyMRI = magnetic resonance imagingOR = operating roomPOD = postoperative dayIVC = inferior vena cavaA. = aortaPS. = psoas.

Cervical Disk Arthroplasty: Surgical Technique.

PURPOSE: Cervical disk arthroplasty (CDA) has emerged as a promising alternative to anterior cervical discectomy and fusion for the management of cervical disk degeneration causing neurological symptoms. This manuscript and accompanying digital content demonstrate the senior author's preferred surgical technique for a single-level CDA. METHODS: CDA is performed using a standard, left-sided Smith Robinson approach. A complete discectomy is performed, with resection of the posterior longitudinal ligament and decompression of the neuroforamina bilaterally. Careful endplate preparation and trial is performed, and the final implant is impacted under a combination of direct visualization and fluoroscopy. Postoperatively, a soft collar is worn for comfort, and the patient is discharged on postoperative day 1 or 2. RESULTS: This video, Supplemental Digital Content 1, http://links.lww.com/CLINSPINE/A254 presents the case of a 43-year old woman with mild cervical spondylosis with a paracentral disk herniation causing left C6 radiculopathy refractory to conservative measures. A C5-6 cervical disk arthroplasty was performed. CONCLUSIONS: CDA presents a motion-sparing alternative to anterior cervical discectomy and fusion and has the potential to reduce adjacent segment disease, though further studies are needed to fully determine its benefits and expanding indications. Careful patient selection and proper surgical technique, as demonstrated here, remain crucial in optimizing outcomes.

Does Low Back Pain Improve Following Total Hip Arthroplasty?

BACKGROUND: Frequently, patients indicated for total hip arthroplasty (THA) present with low back pain (LBP) and hip pain. The purpose of this study was to compare patients whose back pain resolved after THA with those where back pain did not resolve and identify how to predict this using spinopelvic parameters. METHODS: We reviewed a series of 500 patients who underwent THA for unilateral hip osteoarthritis by 2 surgeons. Patients underwent biplanar standing and sitting EOS radiographs pre-operatively. Patients with previous spine surgery or femoral neck fracture were excluded. Demographic data was analyzed at baseline. The Oswestry Disability Index (ODI) scores were calculated pre-operatively and at 1 year postoperatively. Spinopelvic parameters included, pelvic incidence and sacral slope (SS) change from standing to sitting. RESULTS: Two hundred and four patients (41%) had documented LBP before THA. The Oswestry Disability Index (ODI) for patients improved from 38.9 ± 17.8 pre-operatively to 17.0 ± 10.6 at 1 year post-operatively (P < .001). At 1- and 2-year follow-up, resolution of back pain occurred in 168 (82.4%) and 187 (91.2%) patients, respectively. Pelvic incidence was not predictive of back pain resolution. All patients whose back pain resolved had a sacral slope change from standing to sitting of >10°, while those patients whose back pain did not resolve had a change of <10°. CONCLUSION: This study demonstrates that symptomatic low back pain (LBP) resolves in 82% of patients after THA. The results of this study may be used to counsel patients on back pain and its resolution following total hip replacement.

Does robot-assisted navigation influence pedicle screw selection and accuracy in minimally invasive spine surgery?

OBJECTIVE: The accuracy of percutaneous pedicle screw placement has increased with the advent of robotic and surgical navigation technologies. However, the effect of robotic intraoperative screw size and trajectory templating remains unclear. The purpose of this study was to compare pedicle screw sizes and accuracy of placement using robotic navigation (RN) versus skin-based intraoperative navigation (ION) alone in minimally invasive lumbar fusion procedures. METHODS: A retrospective cohort study was conducted using a single-institution registry of spine procedures performed over a 4-year period. Patients who underwent 1- or 2-level primary or revision minimally invasive surgery (MIS)-transforaminal lumbar interbody fusion (TLIF) with pedicle screw placement, via either robotic assistance or surgical navigation alone, were included. Demographic, surgical, and radiographic data were collected. Pedicle screw type, quantity, length, diameter, and the presence of endplate breach or facet joint violation were assessed. Statistical analysis using the Student t-test and chi-square test was performed to evaluate the differences in pedicle screw sizes and the accuracy of placement between both groups. RESULTS: Overall, 222 patients were included, of whom 92 underwent RN and 130 underwent ION MIS-TLIF. A total of 403 and 534 pedicle screws were placed with RN and ION, respectively. The mean screw diameters were 7.25 ± 0.81 mm and 6.72 ± 0.49 mm (p < 0.001) for the RN and ION groups, respectively. The mean screw length was 48.4 ± 4.48 mm in the RN group and 45.6 ± 3.46 mm in the ION group (p < 0.001). The rates of "ideal" pedicle screws in the RN and ION groups were comparable at 88.5% and 88.4% (p = 0.969), respectively. The overall screw placement was also similar. The RN cohort had 63.7% screws rated as good and 31.4% as acceptable, while 66.1% of ION-placed screws had good placement and 28.7% had acceptable placement (p = 0.661 and p = 0.595, respectively). There was a significant reduction in high-grade breaches in the RN group (0%, n = 0) compared with the ION group (1.2%, n = 17, p = 0.05). CONCLUSIONS: The results of this study suggest that robotic assistance allows for placement of screws with greater screw diameter and length compared with surgical navigation alone, although with similarly high accuracy. These findings have implied that robotic platforms may allow for safe placement of the "optimal screw," maximizing construct stability and, thus, the ability to obtain a successful fusion.

The Spine Physical Examination Using Telemedicine: Strategies and Best Practices.

STUDY DESIGN: Technical note. OBJECTIVES: To provide spine surgeons new to telemedicine with a structured physical examination technique based on manual motor testing principles. METHODS: Expert experience describing a series of specific maneuvers for upper and lower extremity strength testing that can be performed using a telemedicine platform. In addition, we offer instruction on "setting up" for these visits and highlight special tests that can be used to diagnose specific cervical and lumbar spine conditions. RESULTS: From our experiences in conducting telemedicine visits, we provide a means of testing and scoring upper and lower extremity strength for interpretation of weakness in the context of traditional manual motor testing. Also, we acknowledge the limitations of a remote examination and discuss maneuvers that cannot be performed remotely. CONCLUSIONS: COVID-19 has drastically altered the delivery of care for patients with spine-related complaints. The need for social distancing has led to the widespread adoption of telemedicine. This technical note provides an urgently needed framework for the standardization of the remote physical exam. Validation of the exam as a diagnostic tool will be a crucial next step in studying the impact of telemedicine.

Indirect Lumbar Decompression Combined With or Without Additional Direct Posterior Decompression: A Systematic Review.

STUDY DESIGN: Systematic review. OBJECTIVE: Indirect decompression via lateral lumbar interbody fusion (LLIF) can ameliorate central and foraminal lumbar stenosis. In severe central stenosis, additional posterior direct decompression is utilized. The aim of this review is to synthesize existing literature on these 2 techniques and identify significant differences in outcomes between isolated indirect decompression via LLIF and combined indirect decompression supplemented with direct posterior decompression. METHODS: A database search algorithm was utilized to query MEDLINE, COCHRANE, and EMBASE to identify literature reporting adult decompression study groups that involved an oblique or lateral fusion approach through September 2020. Improvement in outcomes measures and complication rates were pooled and tested for significance. RESULTS: A total of 110 publications were assessed with 15 studies meeting inclusion criteria, including 557 patients and 1008 levels. Mean age was 63.1 years with BMI of 27.5 kg/m2. For the combined indirect and direct decompression cohort, lumbar lordosis (LL) increased 133.9%, from 22.8o to 48.7o, while the indirect decompression cohort LL increased 8.9%, from 41.9o to 45.5o. Difference in LL improvement between cohorts was insignificant (P > .05). Oswestry Disability Index (ODI) decreased from 36.5 to 19.4 in the combined indirect and direct decompression cohort, and from 44.4 to 23.1 in the indirect decompression cohort. ODI reduction was insignificant (P = .053). CONCLUSIONS: Prior studies of both indirect decompression as well as combined indirect and direct decompression of lumbar spine stenosis are limited by small samples, heterogeneous populations, and lack of direct comparisons. Both procedures result in improved function and pain postoperatively with direct decompression restoring more lordosis in patients with worse preoperative alignment.

Telemedicine in research and training: spine surgeon perspectives and practices worldwide.

PURPOSE: To utilize a global survey to elucidate spine surgeons' perspectives towards research and resident education within telemedicine. METHODS: A cross-sectional, anonymous email survey was circulated to the members of AO Spine, an international organization consisting of spine surgeons from around the world. Questions were selected and revised using a Delphi approach. A major portion of the final survey queried participants on experiences with telemedicine in training, the utility of telemedicine for research, and the efficacy of telemedicine as a teaching tool. Responses were compared by region. RESULTS: A total of 485 surgeons completed the survey between May 15, 2020 and May 31, 2020. Though most work regularly with trainees (83.3%) and 81.8% agreed that telemedicine should be incorporated into clinical education, 61.7% of respondents stated that trainees are not present during telemedicine visits. With regards to the types of clinical education that telemedicine could provide, only 33.9% of respondents agreed that interpretation of physical exam maneuvers can be taught (mean score = - 0.28, SD = ± 1.13). The most frequent research tasks performed over telehealth were follow-up of imaging (28.7%) and study group meetings (26.6%). Of all survey responses provided by members, there were no regional differences (p > 0.05 for all comparisons). CONCLUSIONS: Our study of spine surgeons worldwide noted high agreement among specialists for the implantation of telemedicine in trainee curricula, underscoring the global acceptance of this medium for patient management going forward. A greater emphasis towards trainee participation as well as establishing best practices in telemedicine are essential to equip future spine specialists with the necessary skills for navigating this emerging platform.

Surgical Management of Thoracolumbar Burst Fractures: Surgical Decision-making Using the AOSpine Thoracolumbar Injury Classification Score and Thoracolumbar Injury Classification and Severity Score.

The management of thoracolumbar burst fractures is controversial with no universally accepted treatment algorithm. Several classification and scoring systems have been developed to assist in surgical decision-making. The most widely accepted are the Thoracolumbar Injury Classification and Severity Score (TLICS) and AOSpine Thoracolumbar Injury Classification Score (TL AOSIS) with both systems designed to provide a simple objective scoring criteria to guide the surgical or nonsurgical management of complex injury patterns. When used in the evaluation and treatment of thoracolumbar burst fractures, both of these systems result in safe and consistent patient care. However, there are important differences between the 2 systems, specifically in the evaluation of the complete burst fractures (AOSIS A4) and patients with transient neurological deficits (AOSIS N1). In these circumstances, the AOSpine system may more accurately capture and characterize injury severity, providing the most refined guidance for optimal treatment. With respect to surgical approach, these systems provide a framework for decision-making based on patient neurology and the status of the posterior tension band. Here we propose an operative treatment algorithm based on these fracture characteristics as well as the level of injury.