Morbidly Obese Patients Have Similar Clinical Outcomes and Recovery Kinetics After Minimally Invasive Decompression

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To study the impact of class 2/3 obesity (body mass index, BMI >35) on outcomes following minimally invasive decompression.

SUMMARY OF BACKGROUND DATA

No previous study has analyzed the impact of class 2/3 obesity on outcomes following minimally invasive decompression.

METHODS

Patients who underwent primary minimally invasive decompression were divided into 4 cohorts based on their BMI: normal (BMI 18.5 to <25), overweight (25 to <30), class 1 obesity (30 to <35), and class 2/3 obesity (BMI >35). Outcome measures were: 1) intraoperative variables: operative time, estimated blood loss (EBL); 2) patient reported outcome measures (PROMs) (Oswestry Disability Index, ODI; Visual Analog Scale, VAS back and leg; 12-Item Short Form Survey Physical Component Score, SF-12 PCS); 3) global rating change (GRC), minimal clinically important difference (MCID), and patient acceptable symptom state (PASS) achievement rates; 4) return to activities; and 5) complication and reoperation rates.

RESULTS

838 patients were included (226 normal, 357 overweight, 179 class 1 obesity, 76 class 2/3 obesity). Class 1 and 2/3 obesity groups had significantly greater operative times compared to the other groups. Class 2/3 obesity group had worse ODI, VAS back and SF-12 PCS preoperatively, worse ODI, VAS back, VAS leg and SF-12 PCS at <6 months, and worse ODI and SF-12 PCS at >6 months. However, they had significant improvement in all PROMs at both postoperative timepoints and the magnitude of improvement was similar to other groups. No significant differences were found in MCID and PASS achievement rates, likelihood of betterment on the GRC scale, return to activities, and complication/reoperation rates.

CONCLUSIONS

Class 2/3 obese patients have worse PROMs pre- and post-operatively. However, they show similar improvement in PROMs, MCID and PASS achievement rates, likelihood of betterment, recovery kinetics, and complication/reoperation rates as other BMI groups following minimally invasive decompression.

Temporal Trends of Improvement After Minimally Invasive Transforaminal Lumbar Interbody Fusion

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

To analyze temporal trends in improvement after minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).

SUMMARY OF BACKGROUND DATA

Although several studies have shown that patients improve significantly after MIS TLIF, evidence regarding the temporal trends in improvement is still largely lacking.

METHODS

Patients who underwent primary single-level MIS TLIF for degenerative conditions of the lumbar spine and had a minimum of 2-year follow-up were included. Outcome measures were: 1) patient reported outcome measures (PROMs) (Oswestry Disability Index, ODI; Visual Analog Scale, VAS back and leg; 12-Item Short Form Survey Physical Component Score, SF-12 PCS); 2) global rating change (GRC); 3) minimal clinically important difference (MCID); and 4) return to activities. Timepoints analyzed were preoperative, 2 weeks, 6 weeks, 3 months, 6 months, 1 year, and 2 years. Trends across these timepoints were plotted on graphs.

RESULTS

236 patients were included. VAS back and VAS leg were found to have statistically significant improvement compared to the previous timepoint up to 3 months after surgery. ODI and SF-12 PCS were found to have statistically significant improvement compared to the previous timepoint up to 6 months after surgery. Beyond these timepoints, there was no significant improvement in PROMs. 80% of patients reported feeling better compared to preoperative by 3 months. >50% of patients achieved MCID in all PROMs by 3 months. Most patients returned to driving, returned to work, and discontinued narcotics at an average of 21, 20, and 10 days, respectively.

CONCLUSIONS

Patients are expected to improve up to 6 months after MIS TLIF. Back pain and leg pain improve up to 3 months and disability and physical function improve up to 6 months. Beyond these timepoints, the trends in improvement tend to reach a plateau. 80% of patients feel better compared to preoperative by 3 months after surgery.

The Impact of Posterior Intervertebral Osteophytes on Patient-Reported Outcome Measures After L5-S1 Anterior Lumbar Interbody Fusion and Transforaminal Lumbar Interbody Fusion

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

(1) To develop a reliable grading system to assess the severity of posterior intervertebral osteophytes and (2) to investigate the impact of posterior intervertebral osteophytes on clinical outcomes after L5-S1 decompression and fusion through anterior lumbar interbody fusion (ALIF) and minimally-invasive transforaminal lumbar interbody fusion (MIS-TLIF).

BACKGROUND

There is limited evidence regarding the clinical implications of posterior lumbar vertebral body osteophytes for ALIF and MIS-TLIF surgeries and there are no established grading systems that define the severity of these posterior lumbar intervertebral osteophytes.

PATIENTS AND METHODS

A retrospective analysis of patients undergoing L5-S1 ALIF or MIS-TLIF was performed. Preoperative and postoperative patient-reported outcome measures of the Oswestry Disability Index (ODI) and leg Visual Analog Scale (VAS) at 2-week, 6-week, 12-week, and 6-month follow-up time points were assessed. Minimal clinically important difference (MCID) for ODI of 14.9 and VAS leg of 2.8 were utilized. Osteophyte grade was based on the ratio of osteophyte length to foraminal width. "High-grade" osteophytes were defined as a maximal osteophyte length >50% of the total foraminal width.

RESULTS

A total of 70 consecutive patients (32 ALIF and 38 MIS-TLIF) were included in the study. There were no significant differences between the two cohorts in patient-reported outcome measures or achievement of MCID for Leg VAS or ODI preoperatively or at any follow-ups. On multivariate analysis, neither the surgical approach nor the presence of high-grade foraminal osteophytes was associated with leg VAS or ODI scores at any follow-up time point. In addition, neither the surgical approach nor the presence of high-grade foraminal osteophytes was associated with the achievement of MCID for leg VAS or ODI at 6 months.

CONCLUSION

ALIF and MIS-TLIF are both valid options for treating degenerative spine conditions and lumbar radiculopathy, even in the presence of high-grade osteophytes that significantly occupy the intervertebral foramen.

LEVEL OF EVIDENCE

3.

Practical Answers to Frequently Asked Questions in Anterior Cervical Spine Surgery for Degenerative Conditions

INTRODUCTION

Surgical counseling enables shared decision making and optimal outcomes by improving patients' understanding about their pathologies, surgical options, and expected outcomes. Here, we aimed to provide practical answers to frequently asked questions (FAQs) from patients undergoing an anterior cervical diskectomy and fusion (ACDF) or cervical disk replacement (CDR) for the treatment of degenerative conditions.

METHODS

Patients who underwent primary one-level or two-level ACDF or CDR for the treatment of degenerative conditions with a minimum of 1-year follow-up were included. Data were used to answer 10 FAQs that were generated from author's experience of commonly asked questions in clinic before ACDF or CDR.

RESULTS

A total of 395 patients (181 ACDF, 214 CDR) were included. (1, 2, and 3) Will my neck/arm pain and physical function improve? Patients report notable improvement in all patient-reported outcome measures. (4) Is there a chance I will get worse? 13% (ACDF) and 5% (CDR) reported worsening. (5) Will I receive a significant amount of radiation? Patients on average received a 3.7 (ACDF) and 5.5 mGy (CDR) dose during. (6) How long will I stay in the hospital? Most patients get discharged on postoperative day one. (7) What is the likelihood that I will have a complication? 13% (8% minor and 5% major) experienced in-hospital complications (ACDF) and 5% (all minor) did (CDR). (8) Will I need another surgery? 2.2% (ACDF) and 2.3% (CDR) of patients required a revision surgery. (9 & 10) When will I be able to return to work/driving? Most patients return to working (median of 16 [ACDF] and 14 days [CDR]) and driving (median of 16 [ACDF] and 12 days [CDR]).

CONCLUSIONS

The answers to the FAQs can assist surgeons in evidence-based patient counseling.

Psoas Muscle Health is Correlated with Time to Achieve MCID in Patients with Predominant Axial Back Pain Following Decompression Surgery: Early Results

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To determine the impact of psoas muscle health (cross-sectional area, CSA) on achieving minimal clinically important differences (MCID) in patient-reported outcome measures (PROMs) following laminectomy for patients with predominant back pain (PBP) and leg pain (PLP).

SUMMARY OF BACKGROUND DATA

Psoas muscle health is linked to postoperative outcomes in decompression patients, with MRI-based grading of psoas CSA correlating with these outcomes. However, evidence on its impact on symptomatic recovery, measured by PROMs, is lacking.

METHODS

106 patients with PBP (VAS back >VAS leg) and 139 patients with PLP (VAS leg >VAS back) who underwent laminectomy from 2017-2021 were included. Axial T2 MRI images were analyzed for psoas CSA using a validated method. Based on the lowest-quartile normalized total psoas area (NTPA) thresholds, patients were divided into "Good" and "Poor" muscle health groups. The correlation analyses were performed between the psoas CSA and changes in PROMs. Kaplan-Meier survival analysis was conducted to determine the probability of achieving MCID as a function of time.

RESULTS

Of 106 PBP patients, 83 (78.3%) had good muscle health, 23 (21.6%) had poor muscle health. Of 139 PLP patients, 54 (38.8%) had good muscle health, 85 (61.1%) had poor muscle health. In the PBP group, older age was associated with poor muscle health (69.70±9.26 vs. 59.92±15.01, P=0.0002). For both cohorts, there were no differences in the rate of MCID achievement for any PROMs between the good and poor muscle health groups. In the PBP group, Kaplan-Meier analysis showed patients with good psoas health achieved MCID-VAS back and Oswestry Disability Index (ODI) in median times of 14 and 42 days (P=0.045 and 0.015), respectively.

CONCLUSION

Good psoas muscle health is linked to faster attainment of MCID, especially in patients with PBP compared to PLP after decompression surgery.

LEVEL OF EVIDENCE

3.

Clinical and Radiological Predictors of Slower and Non-Improvement Following Surgical Treatment of L4-5 Degenerative Spondylolisthesis: Preliminary Results

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To identify the predictors of slower and non-improvement following surgical treatment of L4-5 degenerative lumbar spondylolisthesis (DLS).

SUMMARY OF BACKGROUND DATA

There is limited evidence regarding clinical and radiological predictors of slower and non-improvement following surgery for L4-5 DLS.

METHODS

Patients who underwent minimally invasive decompression or fusion for L4-5 DLS and had a minimum of 1-year follow-up were included. Outcome measures were: (1) minimal clinically important difference (MCID), (2) patient acceptable symptom state (PASS), and (3) global rating change (GRC). Clinical variables analyzed for predictors were age, gender, body mass index (BMI), surgery type, comorbidities, anxiety, depression, smoking, osteoporosis, and preoperative patient reported outcome measures (PROMs) (Oswestry Disability Index, ODI; Visual Analog Scale, VAS back and leg; 12-Item Short Form Survey Physical Component Score, SF-12 PCS). Radiological variables analyzed were slip percentage, translational and angular motion, facet diastasis/cyst/orientation, laterolisthesis, disc height, scoliosis, main and fractional curve Cobb angles, and spinopelvic parameters.

RESULTS

233 patients (37% decompression, 63% fusion) were included. At <3 months, high pelvic tilt (PT) (OR 0.92, P 0.02) and depression (OR 0.28, P 0.02) were predictors of MCID non-achievement and GRC non-betterment, respectively. Neither retained significance at >6 months and hence, were identified as predictors of slower improvement. At >6 months, low preoperative VAS leg (OR 1.26, P 0.01) and high facet orientation (OR 0.95, P 0.03) were predictors of MCID non-achievement, high L4-5 slip percentage (OR 0.86, P 0.03) and L5-S1 angular motion (OR 0.78, P 0.01) were predictors of GRC non-betterment, and high preoperative ODI (OR 0.96, P 0.04) was a predictor of PASS non-achievement.

CONCLUSIONS

High PT and depression were predictors of slower improvement and low preoperative leg pain, high disability, high facet orientation, high slip percentage, and L5-S1 angular motion were predictors of non-improvement. However, these are preliminary findings and further studies with homogeneous cohorts are required to establish these findings.

Ninety Percent of Patients Are Satisfied With Their Decision to Undergo Spine Surgery for Degenerative Conditions

STUDY DESIGN

Cross-sectional survey and retrospective review of prospectively collected data.

OBJECTIVE

To explore how patients perceive their decision to pursue spine surgery for degenerative conditions and evaluate factors correlated with decisional regret.

SUMMARY OF BACKGROUND DATA

Prior research shows that one-in-five older adults regret their decision to undergo spinal deformity surgery. However, no studies have investigated decisional regret in patients with degenerative conditions.

METHODS

Patients who underwent cervical or lumbar spine surgery for degenerative conditions (decompression, fusion, or disk replacement) between April 2017 and December 2020 were included. The Ottawa Decisional Regret Questionnaire was implemented to assess prevalence of decisional regret. Questionnaire scores were used to categorize patients into low (<40) or medium/high (≥40) decisional regret cohorts. Patient-reported outcome measures (PROMs) included the Oswestry Disability Index, Patient-reported Outcomes Measurement Information System, Visual Analog Scale (VAS) Back/Leg/Arm, and Neck Disability Index at preoperative, early postoperative (<6 mo), and late postoperative (≥6 mo) timepoints. Differences in demographics, operative variables, and PROMs between low and medium/high decisional regret groups were evaluated.

RESULTS

A total of 295 patients were included (mean follow-up: 18.2 mo). Overall, 92% of patients agreed that having surgery was the right decision, and 90% would make the same decision again. In contrast, 6% of patients regretted the decision to undergo surgery, and 7% noted that surgery caused them harm. In-hospital complications (P=0.02) and revision fusion (P=0.026) were significantly associated with higher regret. The medium/high decisional regret group also exhibited significantly worse PROMs at long-term follow-up for all metrics except VAS-Arm, and worse achievement of minimum clinically important difference for Oswestry Disability Index (P=0.007), Patient-Reported Outcomes Measurement Information System (P<0.0001), and VAS-Leg (P<0.0001).

CONCLUSIONS

Higher decisional regret was encountered in the setting of need for revision fusion, increased in-hospital complications, and worse PROMs. However, 90% of patients overall were satisfied with their decision to undergo spine surgery for degenerative conditions. Current tools for assessing patient improvement postoperatively may not adequately capture the psychosocial values and patient expectations implicated in decisional regret.

Chat Generative Pretraining Transformer Answers Patient-focused Questions in Cervical Spine Surgery

STUDY DESIGN

Review of Chat Generative Pretraining Transformer (ChatGPT) outputs to select patient-focused questions.

OBJECTIVE

We aimed to examine the quality of ChatGPT responses to cervical spine questions.

BACKGROUND

Artificial intelligence and its utilization to improve patient experience across medicine is seeing remarkable growth. One such usage is patient education. For the first time on a large scale, patients can ask targeted questions and receive similarly targeted answers. Although patients may use these resources to assist in decision-making, there still exists little data regarding their accuracy, especially within orthopedic surgery and more specifically spine surgery.

METHODS

We compiled 9 frequently asked questions cervical spine surgeons receive in the clinic to test ChatGPT's version 3.5 ability to answer a nuanced topic. Responses were reviewed by 2 independent reviewers on a Likert Scale for the accuracy of information presented (0-5 points), appropriateness in giving a specific answer (0-3 points), and readability for a layperson (0-2 points). Readability was assessed through the Flesh-Kincaid grade level analysis for the original prompt and for a second prompt asking for rephrasing at the sixth-grade reading level.

RESULTS

On average, ChatGPT's responses scored a 7.1/10. Accuracy was rated on average a 4.1/5. Appropriateness was 1.8/3. Readability was a 1.2/2. Readability was determined to be at the 13.5 grade level originally and at the 11.2 grade level after prompting.

CONCLUSIONS

ChatGPT has the capacity to be a powerful means for patients to gain important and specific information regarding their pathologies and surgical options. These responses are limited in their accuracy, and we, in addition, noted readability is not optimal for the average patient. Despite these limitations in ChatGPT's capability to answer these nuanced questions, the technology is impressive, and surgeons should be aware patients will likely increasingly rely on it.

Comparison of the Safety of Inpatient Versus Outpatient Lumbar Fusion : A Systematic Review and Meta-Analysis

STUDY DESIGN

Systematic Review and Meta-analysis.

OBJECTIVE

The objective of this study is to synthesize the early data regarding and analyze the safety profile of outpatient lumbar fusion.

SUMMARY OF BACKGROUND DATA

Performing lumbar fusion in an outpatient or ambulatory setting is becoming an increasingly employed strategy to provide effective value-based care. As this is an emerging option for surgeons to employ in their practices, the data is still in its infancy.

METHODS

This study was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies that described outcomes of inpatient and outpatient lumbar fusion cohorts were searched from PubMed, Medline, The Cochrane Library, and Embase. Rates of individual medical and surgical complications, readmission, and reoperation were collected when applicable. Patient-reported outcomes (PROMs) were additionally collected if reported. Individual pooled comparative meta-analysis was performed for outcomes of medical complications, surgical complications, readmission, and reoperation. PROMs were reviewed and qualitatively reported.

RESULTS

The search yielded 14 publications that compared outpatient and inpatient cohorts with a total of 75,627 patients. Odds of readmission demonstrated no significant difference between outpatient and inpatient cohorts [OR=0.94 (0.81-1.11)]. Revision surgery similarly was no different between the cohorts [OR=0.81 (0.57-1.15)]. Pooled medical and surgical complications demonstrated significantly decreased odds for outpatient cohorts compared with inpatient cohorts [OR=0.58 (0.34-0.50), OR=0.41 (0.50-0.68), respectively]. PROM measures were largely the same between the cohorts when reported, with few studies showing better ODI and VAS Leg outcomes among outpatient cohorts compared with inpatient cohorts.

CONCLUSION

Preliminary data regarding the safety of outpatient lumbar fusion demonstrates a favorable safety profile in appropriately selected patients, with PROMs remaining comparable in this setting. There is no data in the form of prospective and randomized trials which is necessary to definitively change practice.

Impact of Metabolic Syndrome on Early Postoperative Outcomes After Cervical Disk Replacement: A Propensity-matched Analysis

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To compare the demographics, perioperative variables, and complication rates following cervical disk replacement (CDR) among patients with and without metabolic syndrome (MetS).

SUMMARY OF BACKGROUND DATA

The prevalence of MetS-involving concurrent obesity, insulin resistance, hypertension, and hyperlipidemia-has increased in the United States over the last 2 decades. Little is known about the impact of MetS on early postoperative outcomes and complications following CDR.

METHODS

The 2005-2020 National Surgical Quality Improvement Program was queried for patients who underwent primary 1- or 2-level CDR. Patients with and without MetS were divided into 2 cohorts. MetS was defined, according to other National Surgical Quality Improvement Program studies, as concurrent diabetes mellitus, hypertension requiring medication, and body mass index ≥30 kg/m2. Rates of 30-day readmission, reoperation, complications, length of hospital stay, and discharge disposition were compared using χ2 and Fisher exact tests. One to 2 propensity-matching was performed, matching for demographics, comorbidities, and number of operative levels.

RESULTS

A total of 5395 patients were included for unmatched analysis. Two hundred thirty-six had MetS, and 5159 did not. The MetS cohort had greater rates of 30-day readmission (2.5% vs. 0.9%; P=0.023), morbidity (2.5% vs. 0.9%; P=0.032), nonhome discharges (3% vs. 0.6%; P=0.002), and longer hospital stays (1.35±4.04 vs. 1±1.48 days; P=0.029). After propensity-matching, 699 patients were included. All differences reported above lost significance (P>0.05) except for 30-day morbidity (superficial wound infections), which remained higher for the MetS cohort (2.5% vs. 0.4%, P=0.02).

CONCLUSIONS

We identified MetS as an independent predictor of 30-day morbidity in the form of superficial wound infections following single-level CDR. Although MetS patients experienced greater rates of 30-day readmission, nonhome discharge, and longer lengths of stay, MetS did not independently predict these outcomes after controlling for baseline differences in patient characteristics.

LEVEL OF EVIDENCE

Level III.

Feasibility of Saphenous Nerve Somatosensory-Evoked Potential Intraoperative Monitoring during Lumbar Spine Surgery: Early Results

STUDY DESIGN

Retrospective review.

OBJECTIVE

Assess the feasibility of saphenous nerve somatosensory evoked potentials (SN-SSEP) monitoring in lumbar spine surgeries.

BACKGROUND CONTEXT

SN-SSEPs have been proposed for detecting lumbar plexus and femoral nerve injury during lateral lumbar surgery where tibial nerve (TN)SSEPs alone are insufficient. SN-SSEPs may also be useful in other types of lumbar surgery, as stimulation of SN below the knee derives solely from the L4 root and provides a means of L4 monitoring, whereas TN-SSEPs often do not detect single nerve root injury. The feasibility of routine SN-SSEP monitoring has not been established.

METHODS

A total of 563 consecutive cases using both TN and SN-SSEP monitoring were included. Anesthesia was at the discretion of the anesthesiologist, using an inhalant in 97.7% of procedures. SN stimulation was performed using 13 mm needle electrodes placed below the knee using 200-400 μsec pulses at 15-100 mA. Adjustments to stimulation parameters were made by the neurophysiology technician while obtaining baselines. Data were graded retrospectively for monitorability and cortical response amplitudes were measured by two independent reviewers.

RESULTS

98% of TN-SSEPs and 92.5% of SN-SSEPs were monitorable at baseline, with a mean response amplitude of 1.35 μV for TN-SSEPs and 0.71 μV for SN-SSEPs. A significant difference between the stimulation parameters used to obtain reproducible TN and SN-SSEPs at baseline was observed, with SN-SSEPs requiring greater stimulation intensities. Body mass index (BMI) is not associated with baseline monitorability. Out of 20 signal changes observed, 11 involved SN while TN-SSEPs were unaffected.

CONCLUSION

With adjustments to stimulation parameters, SN-SSEP monitoring is feasible within a large clinical cohort without modifications to the anesthetic plan. Incorporating SN into standard intraoperative neurophysiological monitoring (IONM) protocols for lumbar spine procedures may expand the role of SSEP monitoring to include detecting injury to the lumbar plexus.

LEVEL OF EVIDENCE

3.

Impact of Frailty and Cervical Radiographic Parameters on Postoperative Dysphagia Following Anterior Cervical Spine Surgery

STUDY DESIGN

Retrospective review of a prospectively collected registry.

OBJECTIVE

The purpose of the present study was to investigate the impact of frailty and radiographical parameters on postoperative dysphagia after anterior cervical spine surgery (ACSS).

SUMMARY OF BACKGROUND DATA

There is a growing body of literature indicating an association between frailty and increased postoperative complications following various surgeries. However, few studies have investigated the relationship between frailty and postoperative dysphagia after anterior cervical spine surgery.

MATERIALS AND METHODS

Patients who underwent anterior cervical spine surgery for the treatment of degenerative cervical pathology were included. Frailty and dysphagia were assessed by the modified Frailty Index-11 (mFI-11) and Eat Assessment Tool 10 (EAT-10), respectively. We also collected clinical demographics and cervical alignment parameters previously reported as risk factors for postoperative dysphagia. Multivariable logistic regression was performed to identify the odds ratio (OR) of postoperative dysphagia at early (2-6 weeks) and late postoperative time points (1-2 years).

RESULTS

Ninety-five patients who underwent ACSS were included in the study. Postoperative dysphagia occurred in 31 patients (32.6%) at the early postoperative time point. Multivariable logistic regression identified higher mFI-11 score (OR, 4.03; 95% CI: 1.24-13.16; P =0.021), overcorrection of TS-CL after surgery (TS-CL, T1 slope minus C2-C7 lordosis; OR, 0.86; 95% CI: 0.79-0.95; P =0.003), and surgery at C3/C4 (OR, 12.38; 95% CI: 1.41-108.92; P =0.023) as factors associated with postoperative dysphagia.

CONCLUSIONS

Frailty, as assessed by the mFI-11, was significantly associated with postoperative dysphagia after ACSS. Additional factors associated with postoperative dysphagia were overcorrection of TS-CL and surgery at C3/C4. These findings emphasize the importance of assessing frailty and cervical alignment in the decision-making process preceding ACSS.

Erector Spinae Plane Block Reduces Immediate Postoperative Pain and Opioid Demand After Minimally Invasive Transforaminal Lumbar Interbody Fusion

STUDY DESIGN

Matched cohort comparison.

OBJECTIVE

To determine perioperative outcomes of erector spinae plane (ESP) block for minimally invasive transforaminal lumbar interbody fusion (MI-TLIF).

SUMMARY OF BACKGROUND DATA

There is a paucity of data on the impact of lumbar ESP block on perioperative outcomes and its safety in MI-TLIF.

MATERIALS AND METHODS

Patients who underwent 1-level MI-TLIF and received the ESP block (group E ) were included. An age and sex-matched control group was selected from a historical cohort that received the standard-of-care (group NE). The primary outcome of this study was 24-hour opioid consumption in morphine milligram equivalents. Secondary outcomes were pain severity measured by a numeric rating scale, opioid-related side effects, and hospital length of stay. Outcomes were compared between the two groups.

RESULTS

Ninety-eight and 55 patients were included in the E and NE groups, respectively. There were no significant differences between the two cohorts in patient demographics. Group E had lower 24-hour postoperative opioid consumption ( P = 0.117, not significant), reduced opioid consumption on a postoperative day (POD) 0 ( P = 0.016), and lower first pain scores postsurgery ( P < 0.001). Group E had lower intraoperative opioid requirements ( P < 0.001), and significantly lower average numeric rating scale pain scores on POD 0 ( P = 0.034). Group E reported fewer opioid-related side effects as compared with group NE, although this was not statistically significant. The average highest postoperative pain score within 3 hours postprocedurally was 6.9 and 7.7 in the E and NE cohorts, respectively ( P = 0.029). The median length of stay was comparable between groups with the majority of patients in both groups being discharged on POD 1.

CONCLUSIONS

In our retrospective matched cohort, ESP blocks resulted in reduced opioid consumption and decreased pain scores on POD 0 in patients undergoing MI-TLIF.

LEVEL OF EVIDENCE

Level 3.

Perception of Robotics and Navigation by Spine Fellows and Early Attendings: The Impact of These Technologies on Their Training and Practice

BACKGROUND

There is scant data on the role that robotics and navigation play in spine surgery training and practice of early attendings. This study aimed to assess the impact of navigation and robotics on spine surgery training and practice.

METHODS

A survey gathering information on utilization of navigation and robotics in training and practice was administered to trainees and early attendings.

RESULTS

A total of 51 surveys were returned completed: 71% were attendings (average practice years: 2), 29% were trainees. During training, 22% were exposed to only fluoroscopy, 75% were exposed to navigation, 51% were exposed to robotics, and 40% were exposed to both navigation and robotics. In our sample, 87% and 61% of respondents who had exposure to navigation and robotics, respectively, felt that it had a positive impact on their training. In practice, 28% utilized only fluoroscopy, 69% utilized navigation, 30% utilized robotics, and 28% utilized both navigation and robotics. The top 3 reasons behind positive impact on training and practice were: 1) increased screw accuracy, 2) exposure to upcoming technology, and 3) less radiation exposure. The top 3 reasons behind negative impact were: 1) compromises training to independently place screws, 2) time and personnel requirements, and 3) concerns about availing it in practice. In sum, 76% of attendings felt that they will be utilizing more navigation and robotics in 5 years' time.

CONCLUSIONS

Navigation and robotics have a perceivably positive impact on training and are increasingly being incorporated into practice. However, associated concerns demand spine surgeons to be thoughtful about how they integrate these technologies moving forward.

Association Between Patient Reported Outcomes Measurement Information System Physical Function With Postoperative Pain, Narcotics Consumption, and Patient-Reported Outcome Measures Following Lumbar Microdiscectomy

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To determine association between preoperative Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS-PF) scores with postoperative pain, narcotics consumption, and patient-reported outcome measures (PROMs) following single-level lumbar microdiscectomy.

METHODS

Consecutive patients who underwent single-level lumbar microdiscectomy were identified from May 2017-May 2020. Patients were grouped by their preoperative PROMIS-PF scores: mild disability (score≥40), moderate disability (score 30-39.9), and severe disability (score<30). Preoperative PROMIS-PF subgroups were tested for association with inpatient postoperative pain, total inpatient narcotics consumption, time to narcotic use cessation as well as improvements in postoperative PROMIS-PF, ODI, VAS-Leg Pain, VAS-Back Pain, SF-12 Physical Component Score (PCS), SF-12 Mental Component Score (MCS) at 2-, 6-, 12-weeks, 6-month, 1-year, 2-year follow-up.

RESULTS

A total of 127 patients were included. Patients with greater disability reported higher inpatient maximum Visual Analog Scale (VAS) pain scores (P = .023) and total inpatient narcotics consumption (P = .008) but no difference in time to narcotic cessation after surgery (P = .373). However, patients with greater preoperative disability also demonstrated greater improvement from baseline in PROMIS-PF, ODI, SF-12 PCS, and SF-12 MCS at 2-week follow-up (P < .05). These higher improvements from baseline for patients with greater preoperative disability were sustained for PROMIS-PF, ODI, and VAS-Leg Pain at 2-year follow-up (P < .05).

CONCLUSIONS

Patients with greater preoperative disability, as measured by PROMIS-PF, had increased inpatient postoperative pain and narcotics consumption, but also higher improvement from baseline in long-term PROMs. This data can be utilized for patient counseling and setting expectations.

Recovery Kinetics After Cervical Spine Surgery

STUDY DESIGN

Retrospective review of a prospectively maintained multisurgeon registry.

OBJECTIVE

To study recovery kinetics and associated factors after cervical spine surgery.

SUMMARY OF BACKGROUND DATA

Few studies have described return to activities cervical spine surgery. This is a big gap in the literature, as preoperative counseling and expectations before surgery are important.

MATERIALS AND METHODS

Patients who underwent either anterior cervical discectomy and fusion (ACDF) or cervical disk replacement (CDR) were included. Data collected included preoperative patient-reported outcome measures, return to driving, return to working, and discontinuation of opioids data. A multivariable regression was conducted to identify the factors associated with return to driving by 15 days, return to working by 15 days, and discontinuing opioids by 30 days.

RESULTS

Seventy ACDF patients and 70 CDR patients were included. Overall, 98.2% of ACDF patients and 98% of CDR patients returned to driving in 16 and 12 days, respectively; 85.7% of ACDF patients and 90.9% of CDR patients returned to work in 16 and 14 days; and 98.3% of ACDF patients and 98.3% of CDR patients discontinued opioids in a median of seven and six days. Though not significant, minimal (odds ratio (OR)=1.65) and moderate (OR=1.79) disability was associated with greater odds of returning to driving by 15 days. Sedentary work (OR=0.8) and preoperative narcotics (OR=0.86) were associated with decreased odds of returning to driving by 15 days. Medium (OR=0.81) and heavy (OR=0.78) intensity occupations were associated with decreased odds of returning to work by 15 days. High school education (OR=0.75), sedentary work (OR=0.79), and retired/not working (OR=0.69) were all associated with decreased odds of discontinuing opioids by 30 days.

CONCLUSIONS

Recovery kinetics for ACDF and CDR are comparable. Most patients return to all activities after ACDF and CDR within 16 days. These findings serve as an important compass for preoperative counseling.

Risk factors for failure to achieve minimal clinically important difference following cervical disc replacement

BACKGROUND CONTEXT

While cervical disc replacement (CDR) has been emerging as a reliable and efficacious treatment option for degenerative cervical spine pathology, not all patients undergoing CDR will achieve minimal clinically important difference (MCID) in patient-reported outcome measures (PROMs) postoperatively-risk factors for failure to achieve MCID in PROMs following CDR have not been established.

PURPOSE

To identify risk factors for failure to achieve MCID in Neck Disability Index (NDI, Visual Analog Scale (VAS) neck and arm following primary 1- or 2-level CDRs in the early and late postoperative periods.

STUDY DESIGN

Retrospective review of prospectively collected data.

PATIENT SAMPLE

Patients who had undergone primary 1- or 2-level CDR for the treatment of degenerative cervical pathology at a single institution with a minimum follow-up of 6 weeks between 2017 and 2022.

OUTCOME MEASURES

Patient-reported outcomes: Neck disability index (NDI), Visual analog scale (VAS) neck and arm, MCID.

METHODS

Minimal clinically important difference achievement rates for NDI, VAS-Neck, and VAS-Arm within early (within 3 months) and late (6 months to 2 years) postoperative periods were assessed based on previously established thresholds. Multivariate logistic regressions were performed for each PROM and evaluation period, with failure to achieve MCID assigned as the outcome variable, to establish models to identify risk factors for failure to achieve MCID and predictors for achievement of MCID. Predictor variables included in the analyses featured demographics, comorbidities, diagnoses/symptoms, and perioperative characteristics.

RESULTS

A total of 154 patients met the inclusion criteria. The majority of patients achieved MCID for NDI, VAS-Neck, and VAS-Arm for both early and late postoperative periods-79% achieved MCID for at least one of the PROMs in the early postoperative period, while 80% achieved MCID for at least one of the PROMs in the late postoperative period. Predominant neck pain was identified as a risk factor for failure to achieve MCID for NDI in the early (OR: 3.13 [1.10-8.87], p-value: .032) and late (OR: 5.01 [1.31-19.12], p-value: .018) postoperative periods, and VAS-Arm for the late postoperative period (OR: 36.63 [3.78-354.56], p-value: .002). Myelopathy was identified as a risk factor for failure to achieve MCID for VAS-Neck in the early postoperative period (OR: 3.40 [1.08-10.66], p-value: .036). Anxiety was identified as a risk factor for failure to achieve MCID for VAS-Neck in the late postoperative period (OR: 6.51 [1.91-22.18], p-value: .003). CDR at levels C5C7 was identified as a risk factor for failure to achieve MCID in NDI for the late postoperative period (OR: 9.74 [1.43-66.34], p-value: .020).

CONCLUSIONS

Our study identified several risk factors for failure to achieve MCID in common PROMs following CDR including predominant neck pain, myelopathy, anxiety, and CDR at levels C5-C7. These findings may help inform the approach to counseling patients on outcomes of CDR as the evidence suggests that those with the risk factors above may not improve as reliably after CDR.

Predictors of Subsidence and its Clinical Impact After Expandable Cage Insertion in Minimally Invasive Transforaminal Interbody Fusion

STUDY DESIGN

Retrospective review of prospectively collected multisurgeon data.

OBJECTIVE

Examine the rate, clinical impact, and predictors of subsidence after expandable minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) cage.

SUMMARY OF BACKGROUND DATA

Expandable cage technology has been adopted in MI-TLIF to reduce the risks and optimize outcomes. Although subsidence is of particular concern when using expandable technology as the force required to expand the cage can weaken the endplates, its rates, predictors, and outcomes lack evidence.

MATERIALS AND METHODS

Patients who underwent 1 or 2-level MI-TLIF using expandable cages for degenerative lumbar conditions and had a follow-up of >1 year were included. Preoperative and immediate, early, and late postoperative radiographs were reviewed. Subsidence was determined if the average anterior/posterior disc height decreased by >25% compared with the immediate postoperative value. Patient-reported outcomes were collected and analyzed for differences at the early (<6 mo) and late (>6 mo) time points. Fusion was assessed by 1-year postoperative computed tomography.

RESULTS

One hundred forty-eight patients were included (mean age, 61 yr, 86% 1-level, 14% 2-level). Twenty-two (14.9%) demonstrated subsidence. Although statistically not significant, patients with subsidence were older, had lower bone mineral density, and had higher body mass index and comorbidity burden. Operative time was significantly higher ( P = 0.02) and implant width was lower ( P < 0.01) for subsided patients. Visual analog scale-leg was significantly lower for subsided patients compared with nonsubsided patients at a >6 months time point. Long-term (>6 mo) patient-acceptable symptom state achievement rate was lower for subsided patients (53% vs . 77%), although statistically not significant ( P = 0.065). No differences existed in complication, reoperation, or fusion rates.

CONCLUSIONS

Of the patients, 14.9% experienced subsidence predicted by narrower implants. Although subsidence did not have a significant impact on most patient-reported outcome measures and complication, reoperation, or fusion rates, patients had lower visual analog scale-leg and patient-acceptable symptom state achievement rates at the >6-month time point.

LEVEL OF EVIDENCE

Level 4.

Preoperative Disability Influences Effectiveness of MCID and PASS in Predicting Patient Improvement Following Lumbar Spine Surgery

STUDY DESIGN

Retrospective cohort.

SUMMARY OF BACKGROUND DATA

Although minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) are utilized to interpret Oswestry Disability Index (ODI), it is unclear whether there is a clearly better metric between the two and if not, which metric should be utilized when.

OBJECTIVE

To compare the characteristics of MCID and PASS when interpreting ODI after lumbar spine surgery.

METHODS

Patients who underwent primary minimally invasive transforaminal lumbar interbody fusion or decompression were included. The ODI and global rating change data at 1 year were analyzed. The global rating change was collapsed to a dichotomous outcome variable-(a) improved, (b) not improved The sensitivity, specificity, positive predictive value and negative predictive value of MCID and PASS were calculated for the overall cohort and separately for patients with minimal, moderate, and severe preoperative disability. Two groups with patients who achieved PASS but not MCID and patients who achieved MCID but not PASS were analyzed.

RESULTS

Two hundred twenty patients (mean age 62 y, 57% males) were included. PASS (86% vs. 69%) and MCID (88% vs. 63%) had significantly greater sensitivity in patients with moderate and severe preoperative disability, respectively. Nineteen percent of patients achieved PASS but not MCID and 10% of patients achieved MCID but not PASS, with the preoperative ODI being significantly greater in the latter. Most of these patients still reported improvement with no significant difference between the 2 groups (93% vs. 86%).

CONCLUSION

Significant postoperative clinical improvement is most effectively assessed by PASS in patients with minimal or moderate preoperative disability and by MCID in patients with severe preoperative disability. Adequate interpretation of ODI using the PASS and MCID metrics warrants individualized application as their utility is highly dependent on the degree of preoperative disability.

Quality of Spine Surgery Information on Social Media: A DISCERN Analysis of TikTok Videos

OBJECTIVE

The use of social media applications to disseminate information has substantially risen in recent decades. Spine and back pain-related hashtags have garnered several billion views on TikTok. As such, these videos, which share experiences, offer entertainment, and educate users about spinal surgery, have become increasingly influential. Herein, we assess the quality of spine surgery content TikTok from providers and patients.

METHODS

Fifty hashtags encompassing spine surgery ("#spinalfusion," "#scoliosissurgery," and "#spinaldecompression") were searched using TikTok's algorithm and included. Two independent reviewers rated the quality of each video via the DISCERN questionnaire. Video metadata (likes, shares, comments, views, length) were all collected; type of content creator (musculoskeletal, layperson) and content category (educational, patient experience, entertainment) were determined.

RESULTS

The overall DISCERN score was, on average, 24.4. #Spinalfusion videos demonstrated greater engagement, higher average likes (p = 0.02), and more comments (p < 0.001) compared to #spinaldecompression and #scoliosissurgery. #Spinaldecompression had the highest DISCERN score (p < 0.001), likely explained by the higher percentage of videos that were educational (p < 0.001) and created by musculoskeletal (MSK) professionals (p < 0.001). Compared to laypersons, MSK professionals had significantly higher quality videos (p < 0.001). Similarly, the educational category demonstrated higher quality videos (p < 0.001). Video interaction trended lower with MSK videos and educational videos had the lowest interaction of the content categories (likes: p = 0.023, comments: p = 0.005).

CONCLUSION

The quality of spine surgery videos on TikTok is low. As the influence of the new social media landscape governs how the average person consumes information, MSK providers should participate in disseminating high-quality content.

Preoperative Disability Influences Effectiveness of Minimal Clinically Important Difference and Patient Acceptable Symptom State in Predicting Patient Improvement Following Cervical Spine Surgery

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To compare the characteristics of the minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) metrics when interpreting Neck Disability Index (NDI) following cervical spine surgery.

METHODS

Patients who underwent primary cervical fusion, discectomy, or laminectomy were included. NDI and global rating change (GRC) data at 6 months/1 year/2 years were analyzed. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of MCID and PASS in predicting improvement on GRC were calculated for the overall cohort and separately for patients with minimal (NDI <30), moderate (NDI 30 - 49), and severe (NDI ≥ 50) preoperative disability. Two groups with patients who achieved PASS but not MCID and patients who achieved MCID but not PASS were analyzed.

RESULTS

141 patients (206 responses) were included. PASS had significantly greater sensitivity for the overall cohort (85% vs 73% with MCID, P = .02) and patients with minimal disability (96% vs 53% with MCID, P < .001). MCID had greater sensitivity for patients with severe disability (78% vs 57% with PASS, P = .05). Sensitivity was not significantly different for PASS and MCID in patients with moderate preoperative disability (83% vs 92%, P = .1). 17% of patients achieved PASS but not MCID and 9% of patients achieved MCID but not PASS. Most of these patients still reported improvement with no significant difference between the 2 groups (89% vs 72%, P = .13).

CONCLUSION

PASS and MCID are better metrics for patients with minimal and severe preoperative disability, respectively. Both metrics are equally effective for patients with moderate preoperative disability.

Female Sex and Supine Proximal Lumbar Lordosis Are Associated With the Size of the LLIF "Safe Zone" at L4-L5

STUDY DESIGN

Retrospective chart review.

OBJECTIVE

Identify demographic and sagittal alignment parameters that are independently associated with femoral nerve position at the L4-L5 disk space.

SUMMARY OF BACKGROUND DATA

Iatrogenic femoral nerve or lumbar plexus injury during lateral lumbar interbody fusion (LLIF) can result in neurological complications. The LLIF "safe zone" is the anterior half to two third of the disk space. However, femoral nerve position varies and is inconsistently identifiable on magnetic resonance imaging. The safe zone is also narrowest at L4-L5.

METHODS

An analysis of patients with symptomatic lumbar spine pathology and magnetic resonance imaging with a visibly identifiable femoral nerve evaluated at a single large academic spine center from January 1, 2017, to January 8, 2020, was performed. Exclusion criteria were transitional anatomy, severe hip osteoarthritis, coronal deformity with cobb >10 degrees, > grade 1 spondylolisthesis at L4-L5 and anterior migration of the psoas.Standing and supine lumbar lordosis (LL) and its proximal (L1-L4) and distal (L4-S1) components were measured. Femoral nerve position on sagittal imaging was then measured as a percentage of the L4 inferior endplate. A stepwise multivariate linear regression of sagittal alignment and LL parameters was then performed. Data are written as estimate, 95% CI.

RESULTS

Mean patient age was 58.2±14.7 years, 25 (34.2%) were female and 26 (35.6%) had a grade 1 spondylolisthesis. Mean femoral nerve position was 26.6±10.3% from the posterior border of L4. Female sex (-6.6, -11.1 to -2.1) and supine proximal lumbar lordosis (0.4, 0.1-0.7) were independently associated with femoral nerve position.

CONCLUSIONS

Patient sex and proximal LL can serve as early indicators of the size of the femoral nerve safe zone during a transpsoas LLIF approach at L4-L5.

Percutaneous Transforaminal Endoscopic Discectomy Learning Curve: A CuSum Analysis

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

To describe the learning curve for percutaneous transforaminal endoscopic discectomy (PTED) and demonstrate its efficacy in treating lumbar disc herniation.

SUMMARY OF BACKGROUND DATA

The learning curve for PTED has not yet been standardized in the literature.

PATIENTS AND METHODS

Consecutive patients who underwent lumbar PTED by a single surgeon between December 2020 and 2022 were included. Cumulative sum analysis was applied to operative and fluoroscopy time to assess the learning curve. Inflection points were used to divide cases into early and late phases. The 2 phases were analyzed for differences in operative and fluoroscopy time, length of stay, complications, and patient-reported outcome measures (PROMs). Patient characteristics and operative levels were also compared. PROMs entailed the Oswestry Disability Index, Patient-Reported Outcomes Measurement Information System, Visual Analog Scale Back/Leg, and 12-item Short Form Survey at preoperative, early postoperative (<6 mo), and late postoperative (≥6 mo) time points. PROMs between PTED cases and a comparable cohort of tubular microdiscectomy cases, performed by the same surgeon, were compared.

RESULTS

Fifty-five patients were included. Cumulative sum analysis indicated that both operative and fluoroscopy time diminished rapidly after case 31, suggesting a learning curve of 31 cases (early phase: n = 31; late phase: n = 24). Late-phase cases exhibited significantly lower operative times (85.7 vs . 62.2 min, P = 0.001) and fluoroscopy times (131.0 vs . 97.2 s, P = 0.001) compared with the early-phase cases. Both early and late-phase cases showed significant improvement in all PROMs. There were no differences in PROMs between the patients who underwent PTED and tubular microdiscectomy.

CONCLUSION

The PTED learning curve was found to be 31 cases and did not impact PROMs or complication rates. Although this learning curve reflects the experiences of a single surgeon and may not be broadly applicable, PTED can serve as an effective modality for the treatment of lumbar disc herniation.

Surgeon Experience Influences Robotics Learning Curve for Minimally Invasive Lumbar Fusion: A Cumulative Sum Analysis

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

To analyze the learning curves of three spine surgeons for robotic minimally invasive transforaminal lumbar interbody fusion (MI-TLIF).

SUMMARY OF BACKGROUND DATA

Although the learning curve for robotic MI-TLIF has been described, the current evidence is of low quality with most studies being single-surgeon series.

MATERIALS AND METHODS

Patients who underwent single-level MI-TLIF with three spine surgeons (years in practice: surgeon 1: 4, surgeon 2: 16, and surgeon 3: two) using a floor-mounted robot were included. Outcome measures were operative time, fluoroscopy time, intraoperative complications, screw revision, and patient-reported outcome measures. Each surgeon's cases were divided into successive groups of 10 patients and compared for differences. Linear regression and cumulative sum (CuSum) analyses were performed to analyze the trend and learning curve, respectively.

RESULTS

A total of 187 patients were included (surgeon 1: 45, surgeon 2: 122, and surgeon 3: 20). For surgeon 1, CuSum analysis showed a learning curve of 21 cases with the attainment of mastery at case 31. Linear regression plots showed negative slopes for operative and fluoroscopy time. Both learning phase and postlearning phase groups showed significant improvement in patient-reported outcome measures. For surgeon 2, CuSum analysis demonstrated no discernible learning curve. There was no significant difference between successive patient groups in either operative time or fluoroscopy time. For surgeon 3, CuSum analysis demonstrated no discernible learning curve. Even though the difference between successive patient groups was not significant, cases 11 to 20 had an average operative time of 26 minutes less than cases 1-10), suggesting an ongoing learning curve.

CONCLUSIONS

Surgeons who are well-experienced can be expected to have no or minimal learning curve for robotic MI-TLIF. Early attendings are likely to have a learning curve of around 21 cases with the attainment of mastery at case 31. Learning curve does not seem to impact clinical outcomes after surgery.

LEVEL OF EVIDENCE

Level 3.

Improvement in predominant back pain following minimally invasive decompression for spinal stenosis

OBJECTIVE

The objective of this study was to assess the outcomes of patients with predominant back pain (pBP) undergoing minimally invasive decompression surgery compared with patients with nonpredominant back pain (npBP).

METHODS

This was a retrospective cohort study. Patients were divided into two groups based on the presenting complaint: 1) pBP, defined as visual analog scale (VAS) back pain score > VAS leg pain score; and 2) npBP. Changes in patient-reported outcome measures (PROMs) were compared at the early (< 6 months) and late (≥ 6 months) postoperative time points. Outcomes measures were: 1) PROMs (Oswestry Disability Index [ODI], VAS back and leg pain scores, 12-Item Short-Form Health Survey Physical Component Score [SF-12 PCS], and Patient-Reported Outcomes Measurement Information System Physical Function [PROMIS PF]), and 2) minimal clinically important difference (MCID) achievement rate and time. For the late MCID achievement point, a second analysis was conducted restricting VAS back and leg pain scores only to patients with preoperative scores ≥ 5.

RESULTS

Three hundred ninety patients were included (126 with pBP and 264 with npBP). There were no differences in patient demographics and operated levels. There were no differences in preoperative ODI, SF-12 PCS, and PROMIS PF scores. The pBP cohort had a significantly greater preoperative VAS back pain score than the npBP cohort, whereas the npBP cohort had a significantly greater preoperative VAS leg pain score than the pBP cohort. There were no differences in the absolute values or changes in ODI, VAS back pain, SF-12 PCS, and PROMIS PF scores at any time point. There was a significant difference in the early VAS leg pain scores (greater in npBP) that disappeared by the late postoperative time point. There was no difference in the MCID achievement rate in the ODI, SF-12 PCS, or PROMIS PF scores. By the late postoperative time point, 51.2% and 55.3% achieved an MCID on the ODI, 58.1% and 62.7% on the SF-12 PCS, 60% and 67.6% on the PROMIS PF, 81.1% and 73.2% on VAS back pain scores for those with preoperative scores ≥ 5, and 72% and 83.6% on VAS leg pain scores for those with preoperative scores ≥ 5 for the pBP and npBP cohorts, respectively. Additionally, there were no differences in time to MCID achievement for any PROMs.

CONCLUSIONS

The pBP and npBP cohorts showed similar improvement in PROMs and MCID achievement rates. This result shows that minimally invasive laminectomy is equally effective for patients presenting with pBP or npBP.

Comparison of Robotics and Navigation for Clinical Outcomes After Minimally Invasive Lumbar Fusion

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To compare navigation and robotics in terms of clinical outcomes after minimally invasive transforaminal lumbar interbody fusion (MI-TLIF).

SUMMARY OF BACKGROUND DATA

Although robotics has been shown to have advantages like reduced radiation exposure, greater screw size, and slightly better accuracy over navigation, none of the studies has compared these two modalities in terms of clinical outcomes.

METHODS

Patients who underwent single-level MI-TLIF using robotics or navigation and had a minimum of 1-year follow-up were included. The robotics and navigation groups were compared for improvement in patient-reported outcome measures (PROMs), minimal clinically important difference, patient-acceptable symptom state, response on the global rating change scale, and screw-related complication and reoperation rates.

RESULTS

A total of 278 patients (143 robotics, 135 navigation) were included. There was no significant difference between the robotics and navigation groups in the baseline demographics, operative variables, and preoperative PROMs. Both groups showed significant improvement in PROMs at below six and six months or above, with no significant difference in the magnitude of improvement between the two groups. Most patients achieved minimal clinically important difference and patient-acceptable symptom state and reported feeling better on the global rating change scale, with no significant difference in the proportions between the robotics and navigation groups. The screw-related complication and reoperation rates also showed no significant difference between the two groups.

CONCLUSIONS

Robotics did not seem to lead to significantly better clinical outcomes compared with navigation following MI-TLIF. Although the clinical outcomes may be similar, robotics offers the advantages of reduced radiation exposure, greater screw size, and slightly better accuracy over navigation. These advantages should be considered when determining the utility and cost-effectiveness of robotics in spine surgery. Larger multicenter prospective studies are required in the future to further investigate this subject.

Postoperative Radiculitis After L5-S1 Anterior Lumbar Interbody Fusion

STUDY DESIGN

Retrospective chart review.

OBJECTIVE

This study aimed to examine postoperative radiculitis after isolated L5-S1 anterior lumbar interbody fusion (ALIF), determine which factors contribute to its development, and investigate the comparative outcomes of patients with versus without postoperative radiculitis.

SUMMARY OF BACKGROUND DATA

Both standalone and traditionalALIF are common and safe lumbar spine fusion techniques. Although optimal safety and effectiveness are achieved through appropriate patient selection, postoperative radiculitis after L5-S1 ALIF is a potential complication that seems to be the least predictable in the absence of iatrogenic injury.

PATIENTS AND METHODS

All adult patients (18-80 yr) with preoperative radiculopathies who underwent L5-S1 ALIF by 9 board-certified spine surgeons at a single academic institution from January 2016 to December 2021 with a minimum of 3 months follow-up were included. Patient records were assessed for data on clinical characteristics and patient-reported outcome scores (patient-reported outcome measures). All patient records were evaluated to determine whether postoperative radiculitis developed. Radiographic measurements using x-rays were completed using all available pre and postoperative imaging. Multivariable logistic regressions were performed utilizing radiculitis as the dependent variable and various independent predictor variables.

RESULTS

One hundred forty patients were included, 48 (34%) patients developed postoperative radiculitis, with symptom onset and resolution occurring at 14.5 and 83 days, respectively. The two groups had no differences in preoperative or postoperative radiographic parameters. Multivariable regression showed 3 independent predictors of postoperative radiculitis: methylprednisolone use [OR: 6.032; (95% CI: 1.670-25.568)], increased implant height [OR: 1.509; (95% CI: 1.189-1.960)], and no posterior fixation [OR: 2.973; (95% CI: 1.353-0.806)].

CONCLUSIONS

Of the 34% of patients who developed postoperative radiculitis after L5-S1 ALIF, it resolved on average within 3 months of surgery. These findings may help reduce the risk of undue short-term morbidity after isolated L5-S1 ALIF by informing preoperative counseling and intraoperative decision-making.

Severe Obesity Is an Independent Risk Factor of Early Readmission and Nonhome Discharge After Cervical Disc Replacement

OBJECTIVE

Despite growing interest in cervical disc replacement (CDR) for conditions such as cervical radiculopathy, limited data exists describing the impact of obesity on early postoperative outcomes and complications. These data are especially important as nearly half of the adult population in the United States is expected to become obese (body mass index [BMI] ≥ 30 kg/m2) by 2030. The goal of this study was to compare the demographics, perioperative variables, and complication rates following CDR.

METHODS

The 2005-2020 American College of Surgeons National Surgical Quality Improvement Program datasets were queried for patients who underwent primary 1- or 2-level CDR. Patients were divided into 3 cohorts: Nonobese (BMI: 18.5-29.9 kg/m2), Obese class-I (BMI: 30-34.9 kg/m2), Obese class-II/III (BMI ≥ 35 kg/m2). Morbidity was defined as the presence of any complication within 30 days postoperatively. Rates of 30-day readmission, reoperation, morbidity, individual complications, length of stay, frequency of nonhome discharge disposition were collected.

RESULTS

A total of 5,397 patients were included for analysis: 3,130 were nonobese, 1,348 were obese class I, and 919 were obese class II/III. There were more 2-level CDRs performed in the class II/III cohort compared to the nonobese group (25.7% vs. 21.5%, respectively; p < 0.05). Class-II/III had more nonhome discharges than class I and nonobese (2.1% vs. 0.5% vs. 0.7%, respectively; p < 0.001). Readmission rates differed as well (nonobese: 0.5%, class I: 1.1%, class II/III: 2.1%; p < 0.001) with pairwise significance between class II/II and nonobese. Class II/III obesity was an independent risk factor for both readmission (odds ratio [OR], 3.32; p = 0.002) and nonhome discharge (OR, 2.51; p = 0.02). Neither 30-day reoperation nor morbidity rates demonstrated significance. No mortalities were reported.

CONCLUSION

Although obese class-II/III were risk factors for 30-day readmission and nonhome discharge, there was no significant difference in reoperation rates or morbidity. CDR procedures can continue to be safely preformed independent of obesity status.

Single-position Minimally Invasive Surgery for Correction of Adult Spinal Deformity

Minimally invasive adult spinal deformity (MIS ASD) surgery may offer benefits over conventional techniques in select circumstances. The success of the procedure is based on proper patient selection, restoring adequate alignment, and optimizing fusion. In the past, MIS techniques were limited because of the need to reposition the patient-a source of increased surgical time and potentially patient risk. New developments now allow for single-position, MIS correction of adult deformity. Additional research will be needed to determine the ideal patient for minimally invasive adult spinal deformity surgery and whether prone or lateral single-position confers the best outcomes.

Why Didn't You Walk Yesterday? Factors Associated With Slow Early Recovery After Adult Spinal Deformity Surgery

STUDY DESIGN

This is a retrospective case-control study.

OBJECTIVES

The objectives of this study are to identify (1) risk factors for delayed ambulation following adult spinal deformity (ASD) surgery and (2) complications associated with delayed ambulation.

METHODS

One-hundred and ninety-one patients with ASD who underwent posterior-only fusion (≥5 levels, LIV pelvis) were reviewed. Patients who ambulated with physical therapy (PT) on POD2 or later (LateAmb, n = 49) were propensity matched 1:1 to patients who ambulated on POD0-1 (NmlAmb, n = 49) based on the extent of fusion and surgical invasiveness score (ASD-S). Risk factors, as well as inpatient medical complications were compared. Logistic regressions were used to identify risk factors for late ambulation.

RESULTS

Of the patients who did not ambulate on POD0-1, 32% declined participation secondary to pain or dizziness/fatigue, while 68% were restricted from participation by PT/nursing due to fatigue, inability to follow commands, nausea/dizziness, pain, or hypotension. Logistic regression showed that intraoperative estimated blood loss (EBL) >2L (OR = 5.57 [1.51-20.55], P = .010) was independently associated with an increased risk of delayed ambulation, with a 1.25 times higher risk for every 250 mL increase in EBL (P = .014). Modified 5-Item Frailty Index (mFI-5) was also independently associated with delayed ambulation (OR = 2.53 [1.14-5.63], P = .023). LateAmb demonstrated a higher hospital LOS (8.4 ± 4.0 vs 6.2 ± 2.6, P < .001). The LateAmb group trended toward an increase in medical complications on POD3+ (14.3% vs 26.5%, P = .210).

CONCLUSIONS

EBL demonstrates a dose-response relationship with risk for delayed ambulation. Delayed ambulation increases LOS and may impact medical complications.

Provider Referral Patterns and Surgical Utilization Among New Patients Seen in Spine Clinic

STUDY DESIGN

Retrospective chart review.

OBJECTIVE

The objective of this study was to elucidate the demographics of patient referrals from different sources and identify factors that affect a patient's likelihood of undergoing surgery.

SUMMARY OF BACKGROUND DATA

Despite baseline factors for surgical consideration, such as attempting conservative management, surgeons encounter many patients who are not surgically indicated. Overreferrals, that is, a patient referred to a surgeon that does not need surgery, can result in long wait times, delayed care, worse outcomes, and resource waste.

MATERIALS AND METHODS

All new patients at a single academic institution seen in the clinic by eight spine surgeons between January 1, 2018, and January 1, 2022, were analyzed. Referral types included self-referral, musculoskeletal (MSK), and non-MSK provider referral. Patient demographics included age, body mass index (BMI), zip code as a proxy for socioeconomic status, sex, insurance type, and surgical procedures undergone within 1.5 years postclinic visit. Analysis of variance and a Kruskal-Wallis test was used to compare means among normally and non-normally disturbed referral groups, respectively. Multivariable logistic regressions were run to assess demographic variables associated with undergoing surgery.

RESULTS

From 9356 patients, 84% (7834) were self-referred, 3% (319) were non-MSK, and 13% (1203) were MSK. A statistically significant association with ultimately undergoing surgery was observed with MSK referral type compared with non-MSK referral [odds ratio (OR)=1.37, CI: 1.04-1.82, P =0.0246]. Additional independent variables observed to be associated with patients undergoing surgery included older age (OR=1.004, CI: 1.002-1.007, P =0.0018), higher BMI (OR=1.02, CI: 1.011-1.029, P <0.0001), high-income quartile (OR=1.343, CI: 1.177-1.533, P <0.0001), and male sex (OR=1.189, CI: 1.085-1.302, P =0.0002).

CONCLUSIONS

A statistically significant association with undergoing surgery was observed with a referral by an MSK provider, older age, male sex, high BMI, and a high-income quartile home zip code. Understanding these factors and patterns is critical for optimizing practice efficiency and reducing the burdens of inappropriate referrals.

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.

Poor Muscle Health and Low Preoperative ODI are Independent Predictors for Slower Achievement of MCID After Minimally Invasive Decompression

BACKGROUND CONTEXT

Although some previous studies have analyzed predictors of non-improvement, most of these have focused on demographic and clinical variables and have not accounted for radiological predictors. In addition, while several studies have examined the degree of improvement after decompression, there is less data on the rate of improvement.

PURPOSE

To identify the risk factors and predictors (both radiological and non-radiological) for slower as well as non-achievement of minimal clinically important difference (MCID) after minimally invasive decompression.

DESIGN

Retrospective cohort PATIENT SAMPLE: Patients who underwent minimally invasive decompression for degenerative lumbar spine conditions and had a minimum of 1-year follow-up were included. Patients with preoperative Oswestry Disability Index (ODI) <20 were excluded.

OUTCOME MEASURE

MCID achievement in ODI (cut off 12.8).

METHODS

Patients were stratified into two groups (achieved MCID, did not achieve MCID) at two timepoints (early ≤3 months, late ≥6 months). Non-radiological (age, gender, BMI, comorbidities, anxiety, depression, number of levels operated, preoperative ODI, preoperative back pain) and radiological (MRI - Schizas grading for stenosis, dural sac cross-sectional area, Pfirrmann grading for disc degeneration, psoas cross-sectional area and Goutallier grading, facet cyst/effusion; X-ray - spondylolisthesis, lumbar lordosis, spinopelvic parameters) variables were assessed with comparative analysis to identify risk factors and with multiple regression models to identify predictors for slower achievement of MCID (MCID not achieved by ≤3 months) and non-achievement of MCID (MCID not achieved at ≥6 months).

RESULTS

338 patients were included. At ≤3 months, patients who did not achieve MCID had significantly lower preoperative ODI (40.1 vs. 48.1, p<0.001) and worse psoas Goutallier grading (p=0.048). At ≥6 months, patients who did not achieve MCID had significantly lower preoperative ODI (38 vs. 47.5, p<0.001), higher age (68 vs. 63 years, p=0.007), worse average L1-S1 Pfirrmann grading (3.5 vs. 3.2, p=0.035), and higher rate of pre-existing spondylolisthesis at the operated level (p=0.047). When these and other probable risk factors were put into a regression model, low preoperative ODI (p=0.002) and poor Goutallier grading (p=0.042) at the early timepoint and low preoperative ODI (p<0.001) at the late timepoint came out as independent predictors for MCID non-achievement.

CONCLUSION

After minimally invasive decompression, low preoperative ODI and poor muscle health are risk factors and predictors for slower achievement of MCID. For non-achievement of MCID, low preoperative ODI, higher age, greater disc degeneration, and spondylolisthesis are risk factors and low preoperative ODI is the only independent predictor.

Topical oxygen therapy in acute traumatic musculoskeletal wounds of the foot and ankle

OBJECTIVE

To quantify the reduction in wound size and change in wound quality following low-cost topical oxygen therapy (TOT) in patients with acute traumatic musculoskeletal wounds of the foot and ankle.

METHOD

This prospective interventional study included patients with acute traumatic musculoskeletal wounds of the foot and ankle of <3 weeks' duration after they had undergone debridement and required subsequent wound coverage. A sterile C-Arm cover was used to cover the wound and 100% oxygen was administered at 1 atm, at a rate of 10l/min for 90 minutes on each of four consecutive days, through a suction catheter connected to an oxygen cylinder. The cycle was repeated after a three-day break. Wound surface area (by plotting on graph paper) and wound quality (by modified wound infection checklist score and swabs for culture and Gram staining) were assessed before and after TOT application.

RESULTS

The study cohort included 20 patients ≥18 years of age. There was a statistically significant (p<0.001) reduction in mean wound surface area from 79.3cm² at baseline to 69.6cm² after two cycles of TOT. The mean modified wound infection checklist score was 13.6 and 0.8, respectively, before and after two cycles of TOT, suggesting statistically significant improvement (p=0.02) in wound quality. All patients showed no growth in their wound culture after TOT.

CONCLUSION

TOT appears to be a promising and cost-effective alternative in the management of traumatic wounds. However, future studies with larger sample sizes and control groups for comparison are needed to establish the benefit of TOT in acute traumatic musculoskeletal wounds.

The Role of Intraoperative Neuromonitoring Modalities in Anterior Cervical Spine Surgery

Background: Intraoperative neuromonitoring (IONM) is frequently used during spine surgery to mitigate the risk of neurological injuries. Yet, its role in anterior cervical spine surgery remains controversial. Without consensus on which anterior cervical spine surgeries would benefit the most from IONM, there is a lack of standardized guidelines for its use in such procedures. Purpose: We sought to assess the alerts generated by each IONM modality for 4 commonly performed anterior cervical spinal surgeries: anterior cervical diskectomy and fusion (ACDF), anterior cervical corpectomy and fusion (ACCF), cervical disk replacement (CDR), or anterior diskectomy. In doing so, we sought to determine which IONM modalities (electromyography [EMG], motor evoked potentials [MEP], and somatosensory evoked potentials [SSEP]) are associated with alert status when accounting for procedure characteristics (number of levels, operative level). Methods: We conducted a retrospective review of IONM data collected by Accurate Neuromonitoring, LLC, a company that supports spine surgeries conducted by 400 surgeons in 8 states, in an internally managed database from December 2009 to September 2018. The database was queried for patients who underwent ACCF, ACDF, anterior CDR, or anterior diskectomy in which at least 1 IONM modality was used. The IONM modalities and incidence of alerts were collected for each procedure. The search identified 8854 patients (average age, 50.6 years) who underwent ACCF (n = 209), ACDF (n = 8006), CDR (n = 423), and anterior diskectomy (n = 216) with at least 1 IONM modality. Results: Electromyography was used in 81.3% (n = 7203) of cases, MEP in 64.8% (n = 5735) of cases, and SSEP in 99.9% (n = 8844) of cases. Alerts were seen in 9.3% (n = 671), 0.5% (n = 30), and 2.7% (n = 241) of cases using EMG, MEP and SSEP, respectively. In ACDF, a significant difference was seen in EMG alerts based on the number of spinal levels involved, with 1-level ACDF (6.9%, n = 202) having a lower rate of alerts than 2-level (10.0%, n = 272), 3-level (15.2%, n = 104), and 4-level (23.4%, n = 15). Likewise, 2-level ACDF had a lower rate of alerts than 3-level and 4-level ACDF. A significant difference by operative level was noted in EMG use for single-level ACDF, with C2-C3 having a lower rate of use than other levels. Conclusions: This retrospective review of anterior cervical spinal surgeries performed with at least 1 IONM modality found that SSEP had the highest rate of use across procedure types, whereas MEP had the highest rate of nonuse. Future studies should focus on determining the most useful IONM modalities by procedure type and further explore the benefit of multimodal IONM in spine surgery.

Step-by-step guide to robotic-guided minimally invasive transforaminal lumbar interbody fusion (MI-TLIF)

Robotics in spinal surgery offers a promising potential to refine and improve the minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) technique. Suitable surgeons for this technique include those who are already familiar with robotic-guided lumbar pedicle screw placement and want to advance their skillset by incorporating posterior-based interbody fusion. We provide a step-by-step guide for robotic-guided MI-TLIF. The procedure is divided into 7 practical and detailed techniques. The steps in sequential order include: (I) planning trajectories for pedicle screws and the tubular retractor; (II) robotic-guided pedicle screw placement; (III) placement of tubular retractor; (IV) unilateral facetectomy using the surgical microscope; (V) discectomy & disc preparation; (VI) interbody implant insertion; and (VII) percutaneous rod placement. We standardize surgeon training in robotic MI-TLIF by teaching our spine surgery fellows these 7 key technical steps highlighted in this guide. Current-generation robotics offers integrated navigation capability, K-wireless placement of pedicle screws through a rigid robotic arm, compatibility with tubular retractor systems to perform facetectomy, and allows for placement of interbody devices. We have found robotic-guided MI-TLIF to be a safe procedure that allows for accurate and reliable pedicle screw placement, less collateral damage to the soft tissues of the low back, and decreased radiation exposure.

Improvement following minimally invasive transforaminal lumbar interbody fusion in patients aged 70 years or older compared with younger age groups

OBJECTIVE

The goal of this study was to assess the outcomes of minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) in patients ≥ 70 years old and compare them to younger age groups.

METHODS

This was a retrospective study of data that were collected prospectively. Patients who underwent primary single-level MI-TLIF were included and divided into 3 groups: age < 60, 60-69, and ≥ 70 years. The outcome measures were as follows: 1) patient-reported outcome measures (PROMs) (i.e., visual analog scale [VAS] for back and leg pain, Oswestry Disability Index [ODI], 12-Item Short-Form Health Survey Physical Component Summary [SF-12 PCS]); 2) minimum clinically important difference (MCID) achievement; 3) return to activities; 4) opioid discontinuation; 5) fusion rates; and 6) complications/reoperations.

RESULTS

A total of 147 patients (age < 60 years, 62; 60-69 years, 47; ≥ 70 years, 38) were included. All the groups showed significant improvements in all PROMs at the early (< 6 months) and late (≥ 6 months) time points and there was no significant difference between the groups. Although MCID achievement rates for VAS leg and ODI were similar, they were lower in the ≥ 70-year-old patient group for VAS back and SF-12 PCS. Although the time to MCID achievement for ODI and SF-12 PCS was similar, it was greater in the ≥ 70-year-old patient group for VAS back and leg. There was no significant difference between the groups in terms of return to activities, opioid discontinuation, fusion rates, and complication/reoperation rates.

CONCLUSIONS

Although patients > 70 years of age may be less likely and/or take longer to achieve MCID compared to their younger counterparts, they show an overall significant improvement in PROMs, a similar likelihood of returning to activities and discontinuing opioids, and comparable fusion and complication/reoperation rates following MI-TLIF.

Practical answers to frequently asked questions in minimally invasive lumbar spine surgery

BACKGROUND CONTEXT

Surgical counseling enables shared decision-making (SDM) by improving patients' understanding.

PURPOSE

To provide answers to frequently asked questions (FAQs) in minimally invasive lumbar spine surgery.

STUDY DESIGN

Retrospective review of prospectively collected data.

PATIENT SAMPLE

Patients who underwent primary tubular minimally invasive lumbar spine surgery in form of transforaminal lumbar interbody fusion (MI-TLIF), decompression alone, or microdiscectomy and had a minimum of 1-year follow-up.

OUTCOME MEASURES

(1) Surgical (radiation exposure and intraoperative complications) (2)Immediate postoperative (length of stay [LOS] and complications) (3) Clinical outcomes (Visual Analog Scale- back and leg, VAS; Oswestry Disability Index, ODI; 12-Item Short Form Survey Physical Component Score, SF-12 PCS; Patient-Reported Outcomes Measurement Information System Physical Function, PROMIS PF; Global Rating Change, GRC; return to activities; complications/reoperations) METHODS: The outcome measures were analyzed to provide answers to ten FAQs that were compiled based on the authors' experience and a review of literature. Changes in VAS back, VAS leg, ODI, and SF-12 PCS from preoperative values to the early (<6 months) and late (>6 months) postoperative time points were analyzed with Wilcoxon Signed Rank Tests. % of patients achieving minimal clinically important difference (MCID) for these patient-reported outcome measures (PROMs) at the two time points was evaluated. Changes in PROs from preoperative values too early (<6 months) and late (≥6 months) postoperative time points were analyzed within each of the three groups. Percentage of patients achieving MCID was also evaluated.

RESULTS

Three hundred sixty-six patients (104 TLIF, 147 decompression, 115 microdiscectomy) were included. The following FAQs were answered: (1) Will my back pain improve? Most patients report improvement by >50%. About 60% of TLIF, decompression, and microdiscectomy patients achieved MCID at ≥6 months. (2) Will my leg pain improve? Most patients report improvement by >50%. 56% of TLIF, 67% of decompression, and 70% of microdiscectomy patients achieved MCID at ≥6 months. (3) Will my activity level improve? Most patients report significant improvement. Sixty-six percent of TLIF, 55% of decompression, and 75% of microdiscectomy patients achieved MCID for SF-12 PCS. (4) Is there a chance I will get worse? Six percent after TLIF, 14% after decompression, and 5% after microdiscectomy. (5) Will I receive a significant amount of radiation? The radiation exposure is likely to be acceptable and nearly insignificant in terms of radiation-related risks. (6) What is the likelihood that I will have a complication? 17.3% (15.4% minor, 1.9% major) for TLIF, 10% (9.3% minor and 0.7% major) for decompression, and 1.7% (all minor) for microdiscectomy (7) Will I need another surgery? Six percent after TLIF, 16.3% after decompression, 13% after microdiscectomy. (8) How long will I stay in the hospital? Most patients get discharged on postoperative day one after TLIF and on the same day after decompression and microdiscectomy. (9) When will I be able to return to work? >80% of patients return to work (average: 25 days after TLIF, 14 days after decompression, 11 days after microdiscectomy). (10) Will I be able to drive again? >90% of patients return to driving (average: 22 days after TLIF, 11 days after decompression, 14 days after microdiscectomy).

CONCLUSIONS

These concise answers to the FAQs in minimally invasive lumbar spine surgery can be used by physicians as a reference to enable patient education.

Improvement following minimally invasive lumbar decompression in patients 80 years or older compared with younger age groups

OBJECTIVE

The objective of this study was to assess the outcomes of minimally invasive lumbar decompression in patients ≥ 80 years of age and compare them with those of younger age groups.

METHODS

This was a retrospective cohort study. Patients who underwent primary unilateral laminotomy for bilateral decompression (ULBD) (any number of levels) and had a minimum of 1 year of follow-up were included and divided into three groups by age: < 60 years, 60-79 years, and ≥ 80 years. The outcome measures were 1) patient-reported outcome measures (PROMs) (visual analog scale [VAS] back and leg, Oswestry Disability Index [ODI], 12-Item Short-Form Health Survey [SF-12] Physical Component Summary [PCS] and Mental Component Summary [MCS] scores, and Patient-Reported Outcomes Measurement Information System Physical Function [PROMIS PF]); 2) percentage of patients achieving the minimal clinically important difference (MCID) and the time taken to do so; and 3) complications and reoperations. Two postoperative time points were defined: early (< 6 months) and late (≥ 6 months).

RESULTS

A total of 345 patients (< 60 years: n = 94; 60-79 years: n = 208; ≥ 80 years: n = 43) were included in this study. The groups had significantly different average BMIs (least in patients aged ≥ 80 years), age-adjusted Charlson Comorbidity Indices (greatest in the ≥ 80-year age group), and operative times (greatest in 60- to 79-year age group). There was no difference in sex, number of operated levels, and estimated blood loss between groups. Compared with the preoperative values, the < 60-year and 60- to 79-year age groups showed a significant improvement in most PROMs at both the early and late time points. In contrast, the ≥ 80-year age group only showed significant improvement in PROMs at the late time point. Although there were significant differences between the groups in the magnitude of improvement (least improvement in ≥ 80-year age group) at the early time point in VAS back and leg, ODI, and SF-12 MCS, no significant difference was seen at the late time point except in ODI (least improvement in ≥ 80-year group). The overall MCID achievement rate decreased, moving from the < 60-year age group toward the ≥ 80-year age group at both the early (64% vs 51% vs 41% ) and late (72% vs 58% vs 52%) time points. The average time needed to achieve the MCID in pain and disability increased, moving from the < 60-year age group toward the ≥ 80-year age group (2 vs 3 vs 4 months). There was no significant difference seen between the groups in terms of complications and reoperations except in immediate postoperative complications (5.3% vs 4.8% vs 14%).

CONCLUSIONS

Although in this study minimally invasive decompression led to less and slower improvement in patients ≥ 80 years of age compared with their younger counterparts, there was significant improvement compared with the preoperative baseline.

Association between muscle health and patient-reported outcomes after lumbar microdiscectomy: early results

BACKGROUND CONTEXT

Poor muscle health has been implicated as a source of back pain among patients with lumbar spine pathology. Recently, a novel magnetic resonance imaging (MRI)-based lumbar muscle health grade was shown to correlate with health-related quality of life scores. However, the impact of muscle health on postoperative functional outcomes following spine surgery remains to be investigated.

PURPOSE

To determine whether muscle health grade measured by preoperative psoas and paralumbar muscle cross-sectional areas impact the achievement of minimal clinically important difference (MCID) following lumbar microdiscectomy.

STUDY DESIGN/SETTING

Retrospective cohort study.

PATIENT SAMPLE

Consecutive patients who underwent 1-level lumbar microdiscectomy in a single institution between 2017 and 2021.

OUTCOME MEASURES

Rate of MCID achievement, time to MCID achievement, PROMs including Oswestry Disability Index (ODI), visual analog scale for back pain (VAS back), VAS leg, Short Form 12 Physical Component Summary (SF-12 PCS), SF-12 Mental Component Summary (SF-12 MCS), and Patient Reported Outcomes Measurement Information System Physical Function (PROMIS PF).

METHODS

Two previously validated methods for muscle health grading were applied. Axial T2 MRI were analyzed for muscle measurements. The psoas-based method utilized the normalized total psoas area (NTPA), which is the psoas cross-sectional area divided by the square of patient height (mm²/m²). Patients were divided into low and high NTPA groups based on sex-specific lowest quartile NTPA thresholds. The paralumbar-based method incorporated the paralumbar cross-sectional area normalized by body mass index (PL-CSA/BMI) and Goutallier classification. Score of 1 was added for either PL-CSA/BMI >130 or Goutallier class of ≤2. "Good" muscle health was defined as score of 2, and "poor" muscle health was defined as score of 0 to 1. Prospectively collected PROMs were analyzed at 2-week, 6-week, 3-month, 6-month, 1-year, and 2-year postoperative timepoints. The rate of and time to MCID achievement were compared among the cohorts. Bivariate analyses were performed to assess for correlations between psoas/paralumbar cross-sectional areas and change in PROM scores from baseline.

RESULTS

The total cohort included 163 patients with minimum follow-up of 6 months and mean follow-up of 16.5 months. 40 patients (24.5%) were categorized into the low NTPA group, and 55 patients (33.7%) were categorized into the poor paralumbar muscle group. Low NTPA was associated with older age, lower BMI, and greater frequencies of Charlson Comorbidity Index (CCI) ≥1. Poor paralumbar muscle health was associated with older age, female sex, higher BMI, and CCI ≥1. There were no differences in rates of MCID achievement for any PROMs between low versus high NTPA groups or between poor versus good paralumbar groups. Low NTPA was associated with longer time to MCID achievement for ODI, VAS back, VAS leg, and SF-12 MCS. Poor paralumbar muscle health was associated with longer time to MCID achievement for VAS back, VAS leg, and SF-12 PCS. NTPA negatively correlated with change in VAS back (6-week, 12-week) and VAS leg (6-month). PL-CSA/BMI positively correlated with change in PROMIS-PF at 3 months follow-up.

CONCLUSIONS

Among patients undergoing lumbar microdiscectomy, patients with worse muscle health grades achieved MCID at similar rates but required longer time to achieve MCID. Lower NTPA was weakly correlated with larger improvements in pain scores. PL-CSA/BMI positively correlated with change in PROMIS-PF. Our findings suggest that with regards to functional outcomes, patients with worse muscle health may take longer to recuperate postoperatively compared to those with better muscle health.

Outcomes of cervical disc replacement in patients with neck pain greater than arm pain

BACKGROUND CONTEXT

Although anterior cervical discectomy and fusion is believed to positively impact a patient's radicular symptoms as well as axial neck pain, the outcomes of cervical disc replacement (CDR) with regards to neck pain specifically have not been established.

PURPOSE

Primary: to assess clinical improvement following CDR in patients with neck pain greater than arm pain. Secondary: to compare the clinical outcomes between patients undergoing CDR for predominant neck pain (pNP), predominant arm pain (pAP), and equal neck and arm pain (ENAP).

STUDY DESIGN

Retrospective review of prospectively collected data.

PATIENT SAMPLE

Patients who had undergone one- or two-level CDR for the treatment of degenerative cervical pathology and had a minimum of 6-month follow-up were included and stratified into three cohorts based on their predominant location of pain: pNP, pAP, and ENAP.

OUTCOME MEASURES

Patient-reported outcomes: Neck Disability Index (NDI), Visual Analog Scale (VAS) neck and arm, Short Form 12-Item Physical Health Score (SF12-PHS), Short Form 12-Item Mental Health Score (SF12-MHS), minimal clinically important difference (MCID).

METHODS

Changes in Patient-reported outcomes from preoperative values to early (<6 months) and late (≥6 months) postoperative timepoints were analyzed within each of the three groups. The percentage of patients achieving MCID was also evaluated.

RESULTS

One hundred twenty-five patients (52 pNP, 30 pAP, 43 ENAP) were included. The pNP cohort demonstrated significant improvements in early and late NDI and VAS-Neck, early SF-12 MCS, and late SF-12 PCS. The pAP and ENAP cohorts demonstrated significant improvements in all PROMs, including NDI, VAS-Neck, VAS-Arm, SF-12 PCS, and SF-12 MCS, at both the early and late timepoints. No statistically significant differences were found in the MCID achievement rates for NDI, VAS-Neck, SF-12 PCS, and SF-12 MCS at the late timepoint amongst the three groups.

CONCLUSIONS

CDR leads to comparable improvement in neck pain and disability in patients presenting with neck pain greater than arm pain and meeting specific clinical and radiographic criteria.

Factors Causing Delay in Discharge in Patients Eligible for Ambulatory Lumbar Fusion Surgery

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

To analyze the postoperative factors that led delayed discharge in patients who would have been eligible for ambulatory lumbar fusion (ALF).

SUMMARY OF BACKGROUND DATA

Assessing postoperative inefficiencies is vital to increase the feasibility of ALF.

MATERIALS AND METHODS

Patients who underwent single-level minimally invasive transforaminal lumbar interbody fusion and would have met the eligibility criteria for ALF were included. Length of stay (LOS); time in postanesthesia recovery unit (PACU); alertness and neurological examination, and pain scores at three and six hours; type of analgesia; time to physical therapy (PT) visit; reasons for PT nonclearance; time to per-oral (PO) intake; time to voiding; time to readiness for discharge were assessed. Time taken to meet each discharge criterion was calculated. Multiple regression analyses were performed to study the effect of variables on postoperative parameters influencing discharge.

RESULTS

Of 71 patients, 4% were discharged on the same day and 69% on postoperative day 1. PT clearance was the last-met discharge criterion in 93%. Sixty-six percent did not get PT evaluation on the day of surgery. Seventy-six percent required intravenous opioids and <60% had adequate pain control. Twenty-six percent had orthostatic intolerance. The median postoperative LOS was 26.9 hours, time in PACU was 4.2 hours, time to PO intake was 6.5 hours, time to first void was 6.3 hours, time to first PT visit was 17.7 hours, time to PT clearance was 21.8 hours, and time to discharge readiness was 21.9 hours. Regression analysis showed that time to PT clearance, time to PO intake, time to voiding, time in PACU, and pain score at three hours had a significant effect on LOS.

CONCLUSIONS

Unavailability of PT, surgery after 1  pm , orthostatic intolerance, inadequate pain control, prolonged PACU stay, and long feeding and voiding times were identified as modifiable factors preventing same-day discharge.

LEVEL OF EVIDENCE

4.

Efficacy of Single Injection of Platelet-Rich Plasma in Shoulder Impingement Syndrome

Introduction

To analyze the change in Visual Analog Scale (VAS), QuickDASH score, and the range of motion at the shoulder joint following a single injection of platelet-rich plasma (PRP) in shoulder impingement syndrome.

Methods

Twenty patients (21 shoulders) of either sex above the age of 18 years with a clinical diagnosis of shoulder impingement having a positive shoulder impingement test (positive Hawkins-Kennedy impingement test and/or positive Neer's impingement sign), ultrasonographic confirmation of shoulder impingement, and a failure to respond to standard non-operative methods for a minimum period of four weeks were included in this prospective interventional study. PRP was injected at the proposed site. At three months after the injection, the changes in the VAS, QuickDASH score, and the range of motion at the shoulder joint were analyzed.

Results

There were significant changes in the VAS, QuickDASH score, and range of motion at the shoulder joint following a single injection of PRP.

Conclusions

Platelet-rich plasma (PRP) injection results in a significant decrease in pain and improvement in the range of motion and an overall excellent functional outcome in shoulder impingement syndrome. However, future studies with a bigger sample size and longer follow-up are needed.

Chronic Kidney Disease Presenting With Brown Tumors in the Mandible

A 45-year-old man with stage 4 chronic kidney disease (CKD) on controlled dialysis presented with right-sided painful jaw swelling and protruding into the oral cavity for one year. Examination revealed a 3 x 2.5-cm hard, fixed, and tender swelling of the right mandible. Imaging showed expansile radiolucent lesions in bilateral retromolar regions of the mandible, local destruction of the basal bone, and diffuse osteopenia of the skull. Laboratory investigations revealed elevated parathyroid hormone (PTH), elevated serum calcium, normal serum phosphorous, and elevated alkaline phosphatase (ALP). A provisional diagnosis of tertiary hyperparathyroidism (HPT) causing brown tumors was made, which was confirmed on histopathology. Surgical removal of the lesion and subtotal parathyroidectomy were done followed by cinacalcet and controlled dialysis. This case report highlights the possibility of encountering multiple focal brown tumors in a patient and the importance of their differentiation from malignancy.

Rapid Recurrence of Giant Cell Tumour of C2 Vertebra After Long-Term Denosumab Following Surgical Resection

A 25-year-old man presented with symptoms of cervical myelopathy for 10 days. Imaging revealed an expansile, lytic lesion involving the C2 vertebra completely and compressing the spinal cord, suggestive of giant cell tumor (GCT). Tumor resection and posterior stabilization from C1-C4 were done. Histopathology confirmed the diagnosis of GCT. The patient was kept on adjuvant Denosumab (D-ab) for two years with no signs of recurrence. However, discontinuation of D-ab therapy led to recurrence of the tumor within three months, which was managed with repeated surgical resection and anterior instrumentation followed by radiotherapy. To the best of our knowledge, this is the first reported case of GCT involving the upper cervical spine with rapid recurrence following the stoppage of D-ab therapy.

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.

Sagittal Balance, Pulmonary Function, and Spinopelvic Parameters in Severe Post-Tubercular Thoracic Kyphosis

Study Design

Cross-sectional study.

Purpose

To evaluate sagittal balance, pulmonary function, and spinopelvic parameters in patients with healed spinal tuberculosis with severe thoracic kyphosis.

Overview of Literature

Deterioration of neurological function is an absolute indication of surgical intervention in severe post-tubercular kyphosis, but the relationship of compromise in lung function and spinal alignment with severity of kyphosis is still unclear.

Methods

Twenty patients (age, 14–60 years) with healed spinal tuberculosis with thoracic kyphosis >50° were included. Lateral-view radiography of the whole spine, including both hips, was performed for assessment of kyphotic angle (K angle), sagittal balance, lumbar lordosis, and spinopelvic parameters. Pulmonary function was assessed by measuring the forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and their ratio (FEV1/FVC) by spirometry.

Results

A positive correlation between severity of kyphosis and sagittal imbalance was noted, with compensatory mechanisms maintaining the sagittal balance in only up to 80° of dorsal kyphosis. In >80° of kyphosis, FVC was found to be markedly decreased (mean FVC=50.6%). The mean K angle was lower in subjects with lower thoracic kyphosis. In lower thoracic kyphosis, due to short lordotic and long kyphotic curves, both lumbar lordosis and pelvic retroversion worked at compensation, whereas, in middle thoracic kyphosis, due to long lordotic curve, only lumbar lordosis was required. Normal pulmonary function (mean FVC, 83.0%) and lesser kyphotic deformity (mean K angle in adolescents, 69.8°; in adults, 94.4°) were found in adolescents.

Conclusions

In >80° of thoracic kyphosis, there is sagittal imbalance and a markedly affected pulmonary function. Such patients should be offered corrective surgery if they are symptomatic and medically fit to undergo the procedure. However, whether the surgical procedure would result in improved pulmonary function and sagittal balance needs to be evaluated by a follow-up study.

Osteosynthesis in femoral neck fracture in two patients with ipsilateral lower limb amputation

Femoral neck fracture in lower limb amputees poses treatment problems. The altered biomechanics of the hip in amputees, stump length, associated osteoporosis and difficulty in positioning these patients on the operation table are few of the technical challenges faced by an operating surgeon especially while salvaging the native hip joint. We report a case series of two lower limb amputee patients with fracture neck of femur in whom we salvaged the native hip joint by performing osteosynthesis. We observed satisfactory results of osteosynthesis in both of our patients on follow-up, with both achieving pretrauma ambulatory status in 6-8 weeks postoperatively. We concluded that each lower limb amputee patient with fracture neck of femur should be carefully evaluated on presentation and managed individually. These patients can be positioned and managed by osteosynthesis on a standard operating table or fracture table without requiring any special operating theatre set-up (traction devices).