Elective lumbar fusion in the United States: national trends in inpatient complications and cost from 2002-2014

Spinal fusion surgery use among adults with low back pain enrolled in a digital musculoskeletal program: an observational study

OBJECTIVES

To compare 12-month spinal fusion surgery rates in the setting of low back pain among digital musculoskeletal (MSK) program participants versus a comparison cohort who only received usual care.

STUDY DESIGN

Retrospective cohort study with propensity score matched comparison cohort using commercial medical claims data representing over 100 million commercially insured lives.

METHODS

All study subjects experienced low back pain between January 2020 and December 2021. Digital MSK participants enrolled in the digital MSK low back program between January 2020 and December 2021. Non-participants had low back pain related physical therapy (PT) between January 2020 and December 2021. Digital MSK participants were matched to non-participants with similar demographics, comorbidities and baseline MSK-related medical care use. Spinal fusion surgery rates at 12 months post participation were compared.

RESULTS

Compared to non-participants, digital MSK participants had lower rates of spinal fusion surgery in the post-period (0.7% versus 1.6%; p < 0.001). Additionally, in the augmented inverse probability weighting (AIPW) model, digital MSK participants were found to have decreased odds of undergoing spinal fusion surgery (adjusted odds ratio: 0.64, 95% CI: 0.51-0.81).

CONCLUSIONS

This study provides evidence that participation in a digital MSK program is associated with a lower rate of spinal fusion surgery.

Long-term results and surgical strategy development for degenerative disease treatment in athletes: a retrospective single-center study

PURPOSE

To analyze of the results of spine surgical treatment of athletes with lumbar degenerative disease and development of a surgical strategy based on the preoperative symptoms and radiological changes in the lumbar spine.

METHODS

For 114 athletes with lumbar degenerative disease were included in the present study. Four independent groups were studied: (1) microsurgical/endoscopic discectomy (n = 35); (2) PRP therapy in facet joints (n = 41); (3) total disc replacement (n = 11); (4) lumbar interbody fusion (n = 27). We evaluated postoperative clinical outcomes and preoperative radiological results. The average postoperative follow-up was 5 (3;6), 3.5 (3;5), 3 (2;4) and 4 (3;5) years, respectively. The analysis included an assessment of clinical outcomes (initial clinical symptoms, chronic pain syndrome level according to the VAS, quality of life according to the SF-36 questionnaire, degree of tolerance to physical activity according to the subjective Borg Rating of Perceived Exertion Scale) and radiological data (Dynamic Slip, Dynamic Segmental Angle, degenerative changes in the facet joint according to the Fujiwara classification and disc according to the Pfirrmann classification; changes in the diffusion coefficient using diffusion-weighted MRI).

RESULTS

The median and 25-75% quartiles timing of return to sports were 12.6 (10.2;14.1), 2.8 (2.4;3.7), 9 (6;12), and 14 (9;17) weeks, respectively. We examined the type of surgical treatment utilized, as well as the preoperative clinical symptoms, severity of degenerative changes in the intervertebral disc and facet joint, the timing of return to sports, the level of pain syndrome, the quality of life according to SF-36, and the degree of tolerance to physical activity. We then developed a surgical strategy based on individual preoperative neurological function and lumbar morphological changes.

CONCLUSIONS

In this retrospective study, we report clinical results of four treatment options of lumbar spine degenerative disease in athletes. The use of developed patient selection criteria for the analyzed surgical techniques is aimed at minimizing return-to-play times.

A systematic review and update on diagnosis and treatment of new onset sacroiliac joint dysfunction after lumbar fusion

BACKGROUND

Sacroiliac joint dysfunction (SIJD) after lumbar/lumbosacral fusion has become increasingly recognized as the utilization of lumbar fusion has grown. Despite the significant morbidity associated with this condition, uncertainty regarding its diagnosis and treatment remains. We aim to update the current knowledge of the etiology, diagnosis, and treatment of post-lumbar surgery SIJD.

METHODS

PRISMA guidelines were used to search the PubMed/Medline, Web of Science, Cochrane Reviews, Embase, and OVID databases for literature published in the last 10 years. The ROBIS tool was utilized for risk of bias assessment. Statistical analyses were performed using the R foundation. A Fisher's exact test was performed to determine the risk of SIJD based on operative technique, gender, and symptom onset timeline. Odds ratios were reported with 95% confidence intervals. A p-value [Formula: see text] 0.05 was considered statistically significant.

RESULTS

Seventeen publications were included. The incidence of new onset SIJD was 7.0%. The mean age was 56 years, and the follow-up length was 30 months. SIJD was more common with fixed lumbar fusion vs floating fusion (OR = 1.48 [0.92, 2.37], p = 0.083), fusion of [Formula: see text] 3 segments (p < 0.05), and male gender increased incidence of SIJD (OR = 1.93 [1.27, 2.98], p = 0.001). Intra-articular injection decreased the Visual Analogue Scale (VAS) score by 75%, while radiofrequency ablation (RFA) reduced the score by 90%. An open approach resulted in a 13% reduction in VAS score versus 68 and 29% for SIJ fixation using the iFuse and DIANA approaches, respectively.

CONCLUSIONS

Lumbar fusion predisposes patients to SIJD, likely through manipulation of the SIJ's biomechanics. Definitive diagnosis of SIJD remains multifaceted and a newer modality such as SPECT/CT may find a future role. When conservative measures are ineffective, RFA and SIJ fixation using the iFuse System yield the greatest improvement VAS and ODI.

Are Clinical or Surgical Outcomes Different Based on Whether the Same Surgeon or Hospital System Performs the Spine Revision?

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To determine the effects of discontinuity in care by changing surgeons, health systems, or increased time to revision surgery on revision spine fusion surgical outcomes and patient-reported outcomes.

SUMMARY OF BACKGROUND INFORMATION

Patients undergoing revision spine fusion experience worse outcomes than those undergoing primary lumbar surgery. Those requiring complex revisions are often transferred to tertiary or quaternary referral centers under the assumption that those institutions may be more accustomed at performing those procedures. However, there remains a paucity of literature assessing the impact of discontinuity of care in revision spinal fusions.

METHODS

Patients who underwent revision 1-3 level lumbar spine fusion 2011-2021 were grouped based on (1) revision performed by the index surgeon versus a different surgeon, (2) revision performed within the same versus different hospital system as the index procedure, and (3) length of time from index procedure. Multivariate regression for outcomes controlled for confounding differences.

RESULTS

A total of 776 revision surgeries were included. An increased time interval between the index procedure and the revision surgery was predictive of a lower risk for subsequent revision procedure (odds ratio: 0.57, P =0.022). Revision surgeries performed by the same surgeon predicted a reduced length of hospital stay (β: -0.14, P =0.001). Neither time to revision nor undergoing by the same surgeon or same practice predicted 90-day readmission rates. Patients are less likely to report meaningful improvement in Mental Component Score-12 or Physical Component Score-12 if revision surgery was performed at a different hospital system.

CONCLUSIONS

Patients who have revision lumbar fusions have similar clinical outcomes regardless of whether their surgeon performed the index procedure. However, continuity of care with the same surgeon may reduce hospital length of stay and associated health care costs. The length of time between primary and revision surgery does not significantly impact patient-reported outcomes.

LEVEL OF EVIDENCE

Level III.

Spinolaminar locking plates improve fixation strength compared to pedicle screws: a biomechanical analysis

INTRODUCTION

Pedicle screw loosening is a significant complication of posterior spinal fixation, particularly among osteoporotic patients and in deformity constructs. In orthopedic trauma surgery, locking plates and screws have revolutionized the fixation of osteoporotic fractures. We have combined the traumatology principle of fixed-angle locking plate fixation with the spine principles of segmental instrumentation.

METHODS

A novel spinolaminar locking plate was designed based on morphometric studies of human thoracolumbar vertebrae. The plates were fixed to cadaveric human lumbar spines and connected to form 1-level L1-L2 or L4-L5 constructs and compared to similar pedicle screw constructs. Pure moment testing was performed to assess range of motion before and after 30,000 cycles of cyclic fatigue. Post-fatigue fixture pullout strength was assessed by applying a continuous axial tensile force oriented to the principal axis of the pedicle until pullout was observed.

RESULTS

Spinolaminar plate fixation resulted in superior pullout strength compared to pedicle screws (1,065 ± 400N vs. 714 ± 284N, p = 0.028). Spinolaminar plates performed equivalently to pedicle screws in range of motion reduction during flexion/extension and axial rotation. Pedicle screws outperformed the spinolaminar plates in lateral bending. Finally, no spinolaminar constructs failed during cyclic fatigue testing, whereas one pedicle screw construct did.

CONCLUSIONS

The spinolaminar locking plate maintained adequate fixation post-fatigue, particularly in flexion/extension and axial rotation compared to pedicle screws. Moreover, spinolaminar plates were superior to pedicle screw fixation with respect to cyclic fatiguing and pullout strength. The spinolaminar plates offer a viable option for posterior lumbar instrumentation in the adult spine.

In Vitro and In Vivo Evaluation of Ultrasound-Triggered Release From Novel Spinal Device

OBJECTIVES

Bacterial infection following spinal fusion is a major clinical concern with up to 20% incidence. An ultrasound-triggered bulk-release system to combat postsurgical bacterial survival was designed and evaluated.

METHODS

Polylactic acid (PLA) clips were loaded with vancomycin (VAN) and microbubbles (Sonazoid, GE HealthCare) in vitro. Stability was determined over 14 days. VAN-loaded clips were submerged in water and insonated using a Logiq E10 scanner (GE HealthCare) with a curvilinear C6 probe. Doppler-induced VAN release was quantified using spectrophotometry. For in vivo testing, clips were loaded with methylene blue (MeB) solution and Sonazoid. These clips were implanted into a rabbit along the spine at L2 and L5, as well as a pig at L1 and L3, then insonated in Doppler mode using the C6 probe.

RESULTS

Sonazoid microbubbles were better preserved when incubated in VAN compared with distilled water at 4°C, 25°C, and 37°C incubation temperatures (P = .0131). Contrast enhancement was observed from both solutions when incubated at 4°C storage conditions. Insonated clips achieved average cumulative VAN release of 101.8 ± 2.8% (81.4 ± 2.8 mg) after 72 hours. Uninsonated clips had only 0.3 ± 0.1% (0.3 ± 0.1 mg) average cumulative VAN release (P < .0001). Clips retrieved from the rabbit did not rupture with insonation nor produce MeB staining of surrounding tissues. In the pig, the PLA film was visibly ruptured and MeB tissue was observed following insonation, whereas the uninsonated clip was intact.

CONCLUSION

These results demonstrate ultrasound-triggered release of an encapsulated prophylactic solution and provide an important proof-of-concept for continuing large animal evaluations for translational merit.

Specialty Impact on Patient Outcomes: Paving a Way for an Integrated Approach to Spinal Disorders

Spinal surgical procedures are steadily increasing globally due to broad indications of certain techniques encompassing a wide spectrum of conditions, including degenerative spine disorders, congenital anomalies, spinal metastases, and traumatic spinal fractures. The two specialties, neurosurgery (NS) and orthopedic surgery (OS), both possess the clinical adeptness to perform these procedures. With the advancing focus on comparative effectiveness research, it is vital to compare patient outcomes in spine surgeries performed by orthopedic surgeons and neurosurgeons, given their distinct approaches and training backgrounds to guide hospital programs and physicians to consider surgeon specialty when making informed decisions. Our review of the available literature revealed no significant difference in postoperative outcomes in terms of blood loss, neurological deficit, dural injury, intraoperative complications, and postoperative wound dehiscence in procedures performed by neurosurgeons and orthopedic surgeons. An increase in blood transfusion rates among patients operated by orthopedic surgeons and a longer operative time of procedures performed by neurosurgeons was a consistent finding among several studies. Other findings include a prolonged hospital stay, higher hospital readmission rates, and lower cost of procedures in patients operated on by orthopedic surgeons. A few studies revealed lower sepsis rates unplanned intubation rates and higher incidence of urinary tract infections (UTIs) and pneumonia postoperatively among patient cohorts operated by neurosurgeons. Certain limitations were identified in the studies including the use of large databases with incomplete information related to patient and surgeon demographics. Hence, it is imperative to account for these confounding variables in future studies to alleviate any biases. Nevertheless, it is essential to embrace a multidisciplinary approach integrating the surgical expertise of the two specialties and develop standardized management guidelines and techniques for spinal disorders to mitigate complications and enhance patient outcomes.

Projected Lifetime Cancer Risk Associated With Intraoperative Computed Tomography for Lumbar Spine Surgery

STUDY DESIGN

Retrospective cross-sectional study.

OBJECTIVE

(1) To determine the incremental increase in intraoperative ionizing radiation conferred by computed tomography (CT) as compared with conventional radiography; and (2) to model different lifetime cancer risks contextualized by the intersection between age, sex, and intraoperative imaging modality.

SUMMARY OF BACKGROUND DATA

Emerging technologies in spine surgery, like navigation, automation, and augmented reality, commonly utilize intraoperative CT. Although much has been written about the benefits of such imaging modalities, the inherent risk profile of increasing intraoperative CT has not been well evaluated.

MATERIALS AND METHODS

Effective doses of intraoperative ionizing radiation were extracted from 610 adult patients who underwent single-level instrumented fusion for lumbar degenerative or isthmic spondylolisthesis from January 2015 through January 2022. Patients were divided into those who received intraoperative CT (n=138) and those who underwent conventional intraoperative radiography (n=472). Generalized linear modeling was utilized with intraoperative CT use as a primary predictor and patient demographics, disease characteristics, and preference-sensitive intraoperative considerations ( e.g. surgical approach and surgical invasiveness) as covariates. The adjusted risk difference in radiation dose calculated from our regression analysis was used to prognosticate the associated cancer risk across age and sex strata.

RESULTS

(1) After adjusting for covariates, intraoperative CT was associated with 7.6 mSv (interquartile range: 6.8-8.4 mSv; P <0.001) more radiation than conventional radiography. (2) For the median patient in our population (a 62-year-old female), intraoperative CT use increased lifetime cancer risk by 2.3 incidents (interquartile range: 2.1-2.6) per 10,000. Similar projections for other age and sex strata were also appreciated.

CONCLUSIONS

Intraoperative CT use significantly increases cancer risk compared with conventional intraoperative radiography for patients undergoing lumbar spinal fusions. As emerging technologies in spine surgery continue to proliferate and leverage intraoperative CT for cross-sectional imaging data, strategies must be developed by surgeons, institutions, and medical technology companies to mitigate long-term cancer risks.

Efficacy of Transforaminal Endoscopic Lumbar Discectomy in Elderly Patients Over 65 Years of Age Compared to Young Adults

OBJECTIVE

Spine surgery rates are increasing in the elderly population due to social aging, and it is known that prognoses related to surgery are worse for the elderly compared to younger individuals. However, minimally invasive surgery, such as full endoscopic surgery, is considered safe with low complication rates due to minimal damage to surrounding tissues. In this study, we compared outcomes of transforaminal endoscopic lumbar discectomy (TELD) in elderly and younger patients with disc herniation in the lumbosacral region.

METHODS

We retrospectively analyzed the data of 249 patients who underwent TELD at a single center between January 2016 to December 2019, with a minimum follow-up of 3 years. Patients were allocated to 2 groups: a young group aged ≤ 65 years (n = 202) or an elderly group aged > 65 years (n = 47). We evaluated baseline characteristics, clinical outcomes, surgery-related outcomes, radiological outcomes, perioperative complications, and adverse events during the 3-year follow-up period.

RESULTS

Baseline characteristics, including age, general condition based on American Society of Anesthesiologist physical status classification grade, age-Charlson Comorbidity Index, and disc degeneration, were worse in elderly group (p < 0.001). However, except for leg pain at 4 weeks after surgery, overall outcomes, including pain improvement, radiological change, operation time, blood loss, and hospital stay, were not different between the 2 groups. Furthermore, the rates of perioperative complications (9 patients [4.46%] in the young group and 3 patients [6.38%] in the elderly group, p = 0.578) and adverse events over the 3-year follow-up period (32 patients [15.84%] in the young group and 9 patients [19.15%] in the elderly group, p = 0.582) were comparable in the 2 groups.

CONCLUSION

Our findings suggest that TELD produces similar outcomes in both elderly and younger patients with a herniated disc in the lumbosacral region. TELD can be considered a safe option for appropriately selected elderly patients.

Intraoperative Complications During Orthopaedic Spinal Surgery in a Polypharmacy Patient With Multiple Comorbidities

Orthopedic spinal surgeries, such as laminectomies or decompressions, have the potential to significantly increase quality of life for patients suffering from a spectrum of health issues ranging from neuropathy to chronic pain. Patients suffering from neurological symptoms such as weakness or neuropathy may lose significant function and become unable to perform the activities of daily living, however these delicate surgical interventions also come with significant risks to the health and well-being of those same patients. This is especially true with patients who have predisposing health conditions. Here, we discuss the effects of surgery on a patient with severe obesity, multiple confounding pre-existing conditions, and significant polypharmacy. An initially unremarkable spinal laminectomy and decompression surgery resulted in severe intraoperative complications that necessitated direct admission to the intensive care unit for significant post-operative management before he was able to be discharged safely. Although not a case of incredible rarity, we hope it can contribute to the growing body of data about the role of predisposing health conditions and polypharmacy in calculating and understanding the risks of orthopaedic surgery.

Projected lifetime cancer risk for patients undergoing spine surgery for isthmic spondylolisthesis

BACKGROUND CONTEXT

Radiographs, fluoroscopy, and computed tomography (CT) are increasingly utilized in the diagnosis and management of various spine pathologies. Such modalities utilize ionizing radiation, a known cause of carcinogenesis. While the radiation doses such studies confer has been investigated previously, it is less clear how such doses translate to projected cancer risks, which may be a more interpretable metric.

PURPOSE

(1) Calculate the lifetime cancer risk and the relative contributions of preference-sensitive selection of imaging modalities associated with the surgical management of a common spine pathology, isthmic spondylolisthesis (IS); (2) Investigate whether the use of intraoperative CT, which is being more pervasively adopted, increases the risk of cancer.

STUDY DESIGN/SETTING

Retrospective cross-sectional study carried out within a large integrated health care network.

PATIENT SAMPLE

Adult patients who underwent surgical treatment of IS via lumbar fusion from January 2016 through December 2021.

OUTCOME MEASURES

(1) Effective radiation dose and lifetime cancer risk associated with each exposure to ionizing radiation; (2) Difference in effective radiation dose (and lifetime cancer risk) among patients who received intraoperative CT compared to other intraoperative imaging techniques.

METHODS

Baseline demographics and differences in surgical techniques were characterized. Radiation exposure data were collected from the 2-year period centered on the operative date. Projected risk of cancer from this radiation was calculated utilizing each patient's effective radiation dose in combination with age and sex. Generalized linear modeling was used to adjust for covariates when determining the comparative risk of intraoperative CT as compared to alternative imaging modalities.

RESULTS

We included 151 patients in this cohort. The range in calculated cancer risk exclusively from IS management was 1.3-13 cases of cancer per 1,000 patients. During the intraoperative period, CT imaging was found to significantly increase radiation exposure as compared to alternate imaging modalities (adjusted risk difference (ARD) 12.33mSv; IQR 10.04, 14.63mSv; p<.001). For a standardized 40 to 49-year-old female, this projects to an additional 0.72 cases of cancer per 1,000. For the entire 2-year perioperative care episode, intraoperative CT as compared to other intraoperative imaging techniques was not found to increase total ionizing radiation exposure (ARD 9.49mSv; IQR -0.83, 19.81mSv; p=.072). The effect of intraoperative imaging choice was mitigated in part due to preoperative (ARD 13.1mSv, p<.001) and postoperative CTs (ARD 22.7mSv, p<.001).

CONCLUSIONS

Preference-sensitive imaging decisions in the treatment of IS impart substantial cancer risk. Important drivers of radiation exposure exist in each phase of care, including intraoperative CT and/or CT scans during the perioperative period. Knowledge of these data warrant re-evaluation of current imaging protocols and suggest a need for the development of radiation-sensitive approaches to perioperative imaging.

The Risk of Venous Thromboembolism after Thoracolumbar Spine Surgery: A Population-Based Cohort Study

Background: Although venous thromboembolism (VTE) is rare, including deep vein thrombosis (DVT) and pulmonary embolism (PE), it is a catastrophic complication after spinal surgery. This study was aimed to investigate the risk factors and incidence of VTE after thoracolumbar spine surgery (TLSS). Methods: We retrieved the data of 8697 patients >20 years old who underwent TLSS between 2000 and 2013 from Taiwan’s Longitudinal Health Insurance Database 2000. Each patient was randomly frequency-matched with four individuals who did not undergo TLSS by age, sex, and index year (the control group). Results: The incidence rates of VTE in the TLSS and control groups were 1.84 and 0.69 per 1000 person-years, respectively. The TLSS group had a higher VTE risk (adjusted HR (aHR): 2.13, 95% confidence interval [95%CI]: 1.41−3.21), DVT (aHR: 2.20, 95%CI: 1.40−3.46), and PE (aHR: 1.60, 95%CI: 0.68−3.78) than the control group. The correlated risk factors of VTE included older age (50−64 years: aHR: 2.16, 95%CI: 1.14−4.09; ≥65 years: aHR: 3.18, 95%CI: 1.65−6.13), a history of cancer (aHR: 2.96, 95%CI: 1.58−5.54), heart failure (aHR: 2.19, 95%CI: 1.27−3.78), and chronic kidney disease (aHR: 1.83, 95%CI: 1.18−2.83). Conclusions: The overall VTE risk following TLSS was less than 2% but correlated with certain risk factors. This information could help the spine surgeon help the patient prevent this fatal complication.

Lumbar dynamic pedicle-based stabilization versus fusion in degenerative disease: a multicenter, double-blind, prospective, randomized controlled trial

OBJECTIVE

Fusion is the standard of treatment for degenerative lumbar symptomatic instabilities. Dynamic stabilization is a potential alternative, with the aim of reducing pathological motion. Potential advantages are a reduction of surgical complexity and morbidity. The aim of this study was to assess whether dynamic stabilization is associated with a higher degree of functional improvement while reducing surgical complexity and thereby surgical duration and perioperative complications in comparison with lumbar fusion.

METHODS

This was a multicenter, double-blind, prospective, randomized, 2-arm superiority trial. Patients with symptomatic mono- or bisegmental lumbar degenerative disease with or without stenosis and instability were randomized 1:1 to instrumented fusion or pedicle-based dynamic stabilization. Patients underwent either rigid internal fixation and interbody fusion or pedicle-based dynamic stabilization. The primary endpoint was the Oswestry Disability Index (ODI) score, and secondary endpoints were pain, health-related quality of life, and patient satisfaction at 24 months.

RESULTS

Of 293 patients randomized to fusion or dynamic stabilization, 269 were available for analysis. The duration of surgery was significantly shorter for dynamic stabilization versus fusion, and the blood loss was significantly less for dynamic stabilization (380 ml vs 506 ml). Assessment of primary and secondary outcome parameters revealed no significant differences between groups. There were no differences in the incidence of adverse events.

CONCLUSIONS

Dynamic pedicle-based stabilization can achieve similar clinical outcome as fusion in the treatment of lumbar degenerative instabilities. Secondary failures are not different between groups. However, dynamic stabilization is less complex than fusion and is a feasible alternative.

5-Year Revision Rates After Elective Multilevel Lumbar/Thoracolumbar Instrumented Fusions in Older Patients: An Analysis of State Databases

OBJECTIVE

The purpose of this study wasto evaluate cause-specific 5-year revision rates and risk factors for revision after elective multilevel lumbar instrumented fusion in older patients.

METHODS

Older patients (>60 years) who underwent elective multilevel (3+) lumbar instrumented fusions were identified in Healthcare Cost and Utilization Project state inpatient databases and followed for 5 years for revision operations because of mechanical failure, degenerative disease (DD), infection, postlaminectomy syndrome, and stenosis. Cox proportional hazards multivariate analyses were conducted to determine risk factors associated with revision for each diagnostic cause.

RESULTS

The cohort included 5,636 patients (female-3,285; average age-71.6 years). Most of the operations were 3 to 7 levels (97.4%), and the mean length of stay was 5.4 days. The overall 5-year revision rate was 16.5% with predominant etiologies of DD (50.7%), mechanical failure (32.2%), and stenosis (8.0%). The revision procedure at the index operation was associated with an increased revision risk for DD (hazards ratio [HR] = 1.59, 95% confidence interval [CI], 1.29 to 1.98, P < 0.001) and mechanical failure (HR = 1.56, 95% CI, 1.19 to 2.04, P = 0.020). Male sex was associated with a significantly reduced revision risk for DD (HR = 0.75, 95% CI, 0.62 to 0.91, P = 0.04). Age, race, and number of comorbidities had no notable effect on the overall or cause-specific risk of revision.

DISCUSSION

In this large database analysis, DD and mechanical failure were the most common etiologies comprising a 5-year revision rate of 16.5% after elective multilevel lumbar instrumented fusion in older patients. Revision operations and female patients carried the strongest risks for revision.

Factors Associated with Pain Intensity and Walking Disability After Lumbar Fusion: A Longitudinal Study

STUDY DESIGN

Retrospective longitudinal study.

OBJECTIVE

To identify the preoperative factors associated with postoperative lumbar fusion recovery in back or leg pain, self-reported walking time, and gait speed over a 6-month period.

SUMMARY OF BACKGROUND DATA

The demand for lumbar fusion surgeries has significantly increased over the years. Yet, some patients report persistent postsurgical pain and poor functional outcomes. Unfortunately, the associated risk factors are not well understood.

METHODS

The study analyzed 232 subjects with mono- or bisegmental lumbar fusion surgery who underwent standardized assessment preoperatively and at 4, 12, and 24weeks postoperatively. Preoperative variables collected were demographic, clinical, and psychological variables. Back or leg pain was measured by the Numeric Pain Rating Scale. Walking disability was measured by self-reported walking time and performance-based fast gait speed. Risk factors of pain and walking disability over time were identified using ordinal and linear mixed-effects modeling.

RESULTS

At 6 months post-surgery, 17% of patients reported having moderate or severe back/leg pain and 24% were unable to walk longer than 30 minutes. Greater preoperative self-reported leg weakness frequency and body-mass-index (BMI) were strongly associated with greater pain and walking disability. Additionally, greater preoperative depression symptoms were associated with greater back/leg pain (adjusted odds ratio = 4.0) and shorter walking time (adjusted odds ratio = 2.7)-but not with slower gait speed (difference = 0.01 m/s). Old age and female gender were strongly associated with gait speed but not with self-reported walking time.

CONCLUSION

A sizable proportion of patients had poor pain and walking outcomes even at 6 months post-surgery. Preoperative leg weakness and BMI were consistent risk factors and patients with greater depression symptoms may have poorer self-reported outcomes. Although requiring validation, our study has identified potentially modifiable risk factors which may give clinicians an opportunity to provide early (preoperative) and targeted intervention strategies to optimize postoperative outcomes.

Level of Evidence: NA.

Isthmic Spondylolisthesis is Associated with Less Revisions for Adjacent Segment Disease After Lumbar Spine Fusion Than Degenerative Spinal Conditions: A 10-Year Follow-Up Study

STUDY DESIGN

Prospective, follow-up study.

OBJECTIVE

We aim to compare the rate of revisions for ASD after LSF surgery between patients with IS and DLSD.

SUMMARY OF BACKGROUND DATA

ASD is a major reason for late reoperations after LSF surgery. Several risk factors are linked to the progression of ASD, but the understanding of the underlying mechanisms is imperfect. If IS infrequently becomes complicated with ASD, it would emphasize the role of the ongoing degenerative process in spine in the development of ASD.

METHODS

365 consecutive patients that underwent elective LSF surgery were followed up for an average of 9.7 years. Surgical indications were classified into 1) IS (n = 64), 2) DLSD (spinal stenosis with or without spondylolisthesis) (n = 222), and 3) other reasons (deformities, postoperative conditions after decompression surgery, posttraumatic conditions) (n = 79). All spinal reoperations were collected from hospital records. Rates of revisions for ASD were determined using Kaplan-Meier methods.

RESULTS

Altogether, 65 (17.8%) patients were reoperated for ASD. The incidences of revisions for ASD in subgroups were 1) 4.8% (95% CI: 1.6%-22.1%); 2) 20.5% (95% CI: 15.6%-26.7%); 3) 20.6% (95% CI: 12.9%-31.9%). After adjusting the groups by age, sex, fusion length, and the level of the caudal end of fusion, when comparing with IS group, the other groups had significantly higher hazard ratios (HR) for the revision for ASD [2) HR (95% CI) 3.92 (1.10-13.96), P = 0.035], [3) HR (95% CI) of 4.27 (1.11-15.54), P = 0.036].

CONCLUSION

Among patients with IS, the incidence of revisions for ASD was less than a 4th of that with DLSD. Efforts to prevent the acceleration of the degenerative process at the adjacent level of fusion are most important with DLSD.Level of Evidence: 3.

C-reactive protein in spinal surgery: more predictive than prehistoric

PURPOSE

In spinal surgery, surgical site infections (SSI) after dorsal spondylodesis lead to severe short- and long-term complications. Despite various clinical and serological evidence, the detection of a postoperative SSI remains crucial. In this retrospective cohort study, we determined the prognostic value of C-reactive protein (CRP) kinetics after open reduction and dorsal spondylodesis in the development of a SSI.

METHODS

We retrospectively analyzed 192 patients from 2016 to 2018 undergoing open reduction and dorsal spondylodesis with and without SSI for 20 days at a level-I trauma center and assessed their serological and clinical characteristics.

RESULTS

On day 7 and 8 after surgery, patients who developed a SSI displayed significantly higher CRP levels. A second peak after the initial maximum of CRP and a restricted failure to decline as well as a maximum CRP of more than 225 mg/l predict an infectious complication with a sensitivity of 92.9%, and a specificity of 78.2%. A binary logistic regression leads to 85.7% and 69.7%, respectively. A one-phase decay exponential regression can predict 75.6% of the variance after the initial peak of CRP.

CONCLUSION

Our study demonstrates a high value of postoperative CRP kinetics in SSI detection after dorsal spondylodesis. Moreover, we observed typical CRP levels with a specific course as indicative predictors that may facilitate an early SSI detection in clinical practice.