Incidence and risk factors of persistent low back pain following posterior decompression and instrumented fusion for lumbar disk herniation

Fatty Infiltration in Paraspinal Muscles: Predicting the Outcome of Lumbar Surgery and Postoperative Complications

Lumbar spine disorders often cause lower back pain, lower limb radiating pain, restricted movement, and neurological dysfunction, which seriously affect the quality of life of middle-aged and older people. It has been found that pathological changes in the spine often cause changes in the morphology and function of the paraspinal muscles (PSMs). Fatty infiltration (FI) in PSMs is closely associated with disc degeneration and Modic changes. And FI causes inflammatory responses that exacerbate the progression of lumbar spine disease and disrupt postoperative recovery. Magnetic resonance imaging can better distinguish between fat and muscle tissue with the threshold technique. Three-dimensional magnetic resonance imaging multi-echo imaging techniques such as water-fat separation and proton density are currently popular for studying FI. Muscle fat content obtained based on these imaging sequences has greater accuracy, visualization, acquisition speed, and utility. The proton density fat fraction calculated from these techniques has been shown to evaluate more subtle changes in PSMs. Magnetic resonance spectroscopy can accurately reflect the relationship between FI and the degeneration of PSMs by measuring intracellular and extracellular lipid values to quantify muscle fat. We have pooled and analyzed published studies and found that patients with spinal disorders often exhibit FI in PSMs. Some studies suggest an association between FI and adverse surgical outcomes, although conflicting results exist. These suggest that clinicians should consider FI when assessing surgical risks and outcomes. Future studies should focus on understanding the biological mechanisms underlying FI and its predictive value in spinal surgery, providing valuable insights for clinical decision-making.

Multifidus lesions: A possible pathological component in patients with low back pain after posterior lumbar surgery

There are few histological studies on multifidus after lumbar surgery, and it is not clear whether multifidus changes affect the clinical outcome after lumbar surgery. The aim of this study was to investigate the relationship between multifidus changes and clinical outcomes after lumbar surgery. Patients underwent internal fixation removal after lumbar posterior surgery were enrolled. Patients were divided into a low back pain (LBP) group (n = 15) and a non-low back pain (non-LBP) group (n = 10).The Oswestry disability index (ODI) and visual analog scale (VAS) were completed. 18 patients with lumbar fracture surgery were included as the control group. Multifidus morphological changes were observed by hematoxylin and eosin and Masson staining. The expression of TGF-β1 was observed by immunohistochemistry, immunofluorescence and Western blot. The cross-sectional area (CSA) of the multifidus in the non-LBP group and the control group were greater than those in the LBP group. TGF-β1 expression and gray value ratio in the non-LBP group and the control group were lower than those in the LBP group. The multifidus CSA and TGF-β1 expression in multifidus were strongly correlated with ODI and VAS. Patients with LBP after posterior lumbar surgery suffered from atrophy and fibrosis lesions in the multifidus, and the degree of multifidus lesions was closely related to dysfunction and pain, which might be one of the causes of LBP after posterior lumbar surgery.

Management of recurrent lumbar disc herniation: a comparative analysis of posterior lumbar interbody fusion and repeat discectomy

Background

For recurrent lumbar disc herniation, many experts suggest a repeat discectomy without stabilization due to its minimal tissue manipulation, lower blood loss, shorter hospital stay, and lower cost, recent research on the role of instability in disc herniation has made fusion techniques popular among spinal surgeons. The authors compare the postoperative outcomes of posterior lumbar interbody fusion (PLIF) and repeat discectomy for same-level recurrent disc herniation.

Methods

The patients included had previously undergone discectomy and presented with a same-level recurrent lumbar disc herniation. The patients were placed into two groups: 1) discectomy only, 2) PLIF based on the absence or presence of segmental instability. Preoperative and postoperative Oswestry disability index scores, duration of surgery, blood loss, duration of hospitalization, and complications were analyzed.

Results

The repeat discectomy and fusion groups had 40 and 34 patients, respectively. The patients were followed up for 2.68 (1-4) years. There was no difference in the duration of hospitalization (3.73 vs. 3.29 days P=0.581) and operative time (101.25 vs. 108.82 mins, P=0.48). Repeat discectomy had lower intraoperative blood loss, 88.75 ml (50-150) versus 111.47 ml (30-250) in PLIF (P=0.289). PLIF had better ODI pain score 4.21 (0-10) versus 9.27 (0-20) (P-value of 0.018). Recurrence was 22.5% in repeat discectomy versus 0 in PLIF.

Conclusion

PLIF and repeat discectomy for recurrent lumbar disc herniation have comparable intraoperative blood loss, duration of surgery, and hospital stay. PLIF is associated with lower durotomy rates and better long-term pain control than discectomy. This is due to recurrence and progression of degenerative process in discectomy patients, which are eliminated and slowed, respectively, by PLIF.

Analysis of Chronic Low Back Pain Caused by Lumbar Microinstability After Percutaneous Endoscopic Transforaminal Discectomy: A Retrospective Study

Objective

Chronic low back pain (CLBP) after percutaneous endoscopic transforaminal discectomy (PTED) surgery may be caused by preoperative lumbar microinstability (MI). However, there is a paucity of research on the relationship between lumbar microinstability and chronic low back pain. The purpose of this article is to assess the preoperative radiographic characteristics of patients and evaluate the effects of lumbar microinstability on patient-reported outcomes among single-level lumbar disc herniation (LDH) patients who underwent PTED.

Methods

This study retrospectively reviewed the radiographic characteristics of a consecutive series of 127 patients with low back pain and leg pain caused by single-level LDH underwent PTED from August 2018 to March 2021. They were divided into three groups according to the radiographic parameters: the stable group (Group S), the dysfunctional group (Group D), and the microinstability group (Group M). The visual analogue scale (VAS) scores for leg and low back pain and Oswestry Disability Index (ODI) were evaluated preoperatively and postoperatively. Logistic regression analysis was used to identify independent risk factors for CLBP.

Results

Compared with Group D and Group S, Group M had the highest ODI scores (P < 0.01) and VAS scores (low back pain) (P < 0.01) after 1 year, while there were no significant differences in the VAS scores for leg pain at different time points after surgery (P > 0.05). In addition, the logistic regression analysis results regarding CLBP revealed that muscle fatty degeneration on MRI (95% CI, 1.20-8.51, P = 0.02), and facet tropism (95% CI, 1.39 -11.37, P = 0.01) may be independent risk factors.

Conclusion

Patients with lumbar microinstability may have CLBP after PTED, so patients with lumbar microinstability may need to take internal fixation surgery to solve their symptoms.

The Association Between Sagittal Spinopelvic Alignment and Persistent Low Back Pain After Posterior Lumbar Interbody Fusion for Treatment of Mild L5-S1 Spondylolisthesis: A Retrospective Study

Introduction

The aim of this study was to explore the association between sagittal spinopelvic alignment and persistent low back pain (PLBP) following posterior decompression and instrumented fusion for mild L5-S1 spondylolisthesis.

Methods

By retrieving medical records from January 2015 to April 2020, 200 patients following PLIF for mild L5-S1 spondylolisthesis were retrospectively reviewed. Patients were divided into two groups: PLBP group and non-PLBP group. The baseline characteristics and radiographic parameters were analyzed and compared between groups.

Results

The PLBP group comprised 26 patients, and the non-PLBP group comprised 174 patients. No significant differences in preoperative spinopelvic parameters were found between the two groups (p > 0.05). There were statistically significant differences between the preoperative and postoperative variations of LL, SL, LSA, SD, and HOD spinopelvic parameters, regardless of group (p < 0.05). Postoperative PT and SS differed significantly between the PLBP group and non-PLBP group (p < 0.05). In the PLBP group, there were no significant differences between preoperative and postoperative PT; the same applied to SS. However, significant differences were found for the variations in preoperative and postoperative PT and SS between the two groups. The ΔPT was found as an independent risk factor for postoperative PLBP.

Conclusion

Patients with mild L5-S1 spondylolisthesis with PLBP after posterior lumbar spinal fusion had decreased SS and increased PT.

VAS and NRS, Same or Different? Are Visual Analog Scale Values and Numerical Rating Scale Equally Viable Tools for Assessing Patients after Microdiscectomy?

Objectives

To compare the viability of the numerical rating scale (NRS) and the visual analogue scale (VAS) as a pain assessment tools among a large cohort of patients who underwent microdiscectomy. Summary of Background Data. The pain intensity (PI) reduction is a parameter of surgical treatment efficacy. The two most commonly used scales of PI are NRS and VAS. Many studies have shown strong similarities between those two scales, but the direct interchange is difficult.

Methods

Patients, who underwent microdiscectomy, were prospectively enrolled into the study and assessed using VAS and NRS for the back (NRS-B) and the leg (NRS-L), Short Form of McGill Pain Questionnaire (SF-MPQ) included Pain Rating Index (PRI) and Oswestry Disability Index (ODI) 1 day before and 1 month and 3 months after the procedure.

Results

131 patients were included in the study. NRS-L, NRS-B, VAS, and ODI were significantly lower (p < 0.001) 1 month after microdiscectomy. NRS-L and NRS-B ratings remained at a similar level while VAS and ODI decreased after 3 months. The rate of decline of PI measured by NRS-L correlated statistically significant (rs = 0.366; p < 0.001) with ODI 1 month after surgery. Before surgery, the most significant correlation was found between ODI and NRS-L (rs = 0.494; p < 0.001), the lowest with NRS-B (rs = 0.319; p < 0.001). 3 months after surgery, there was higher correlations between ODI and VAS (rs = 0.634) than NRS-L (rs = 0.265). PRI correlated significantly (p < 0.001) and more stronger with VAS than with NRS-L and NRS-B in every points of assessment.

Conclusion

The results showed that PI measurements by NRS-L/NRS-B and VAS mutually correlate and impair functionality evaluated by ODI (convergent validity) but in different modes (differential validity). NRS and VAS are not parallel scales and assess different aspects of pain. The measurement of NRS-L 1 month after microdiscectomy seems to give quick insight into the effectiveness of the procedure.

The effect of posterior lumbar dynamic fixation and intervertebral fusion on paraspinal muscles

BACKGROUND

The aim of this study was to analyze the effect of unilateral K-rod dynamic internal fixation on paraspinal muscles for lumbar degenerative diseases.

METHODS

This study retrospectively collected 52 patients who underwent lumbar surgery with the K-rod group or PLIF. The operation time, intraoperative blood loss, postoperative drainage volume, postoperative exercise time were compared in the two groups. The visual analog scale (VAS) score and the oswestry dysfunction index (ODI) were employed to evaluate the clinical outcomes. The functional cross-sectional area (FCSA) of the paraspinal muscles and paraspinal muscles fat infiltration were measured to assess on the paraspinal muscles.

RESULTS

As compared with the PLIF group, the operation time, the postoperative time in the field, and the average postoperative hospital stay in the K-rod internal fixation group were significantly shortened. At the last follow-up, both the groups showed significant improvement in the VAS score and ODI. The FCSA atrophy of the upper and lower adjacent segments (UAS and LAS) of the K-rod internal group was significantly less than that of the PLIF group. The extent of increase in the fatty infiltration of the paraspinal muscles in the K-rod group was significantly lesser than that in the PLIF group. The postoperative low back pain of the two groups of patients was significantly positively correlated with the FCSA atrophy.

CONCLUSIONS

As compared to PLIF, the posterior lumbar unilateral K-rod dynamic internal fixation showed significantly lesser paraspinal muscle atrophy and fatty infiltration, which were significantly positively correlated with postoperative low back pain.

Return to work in patients with lumbar disc herniation undergoing fusion

BACKGROUND

Lumbar disc herniation (LDH) is a common problem. When surgical treatment is required, the intervention is typically decompression without fusion. Successful return-to-work (RTW) is a standard expectation with these limited procedures. Occasionally, the size or location of the disc herniation suggests the need for fusion, but the inability to RTW is a significant concern in these cases. The purpose of this study is to determine if the addition of lumbar fusion, as compared to decompression alone, will substantially diminish RTW in patients with lumbar disc herniation.

METHODS

This is a longitudinal cohort study using prospectively collected data from the Quality and Outcomes Database (QOD). Patients with LDH, eligible to RTW (not retired, a student, or on disability) with complete 12-month follow-up data, were identified. Standard demographic and surgical variables, patient-reported outcomes (PROs), and RTW status at 3 and 12 months were collected.

RESULTS

Of the 5062 patients identified, 4560 (90%) had decompression alone and 502 (10%) had a concurrent fusion. Age and gender were similar in the two groups. The fusion group had worse back pain (NRS 6.52 vs. 5.96) and less leg pain (6.31 vs. 7.01) at baseline compared to the no fusion group. Statistically significant improvement in all PROs was seen in both groups. RTW at 3 months post-op was seen in 85% of decompression cases and 66% of cases with supplemental fusion. At 12 months post-op, RTW increased to 93% and 82%, respectively.

CONCLUSION

The need for fusion in LDH cases is unusual, seen in only 10% of cases in this series. The addition of fusion decreased the RTW rate from 85 to 66% at 3 months and from 93 to 82% at 12 months post-op. While the difference is significant, the ultimate deterioration in RTW may be less than anticipated. A reasonable RTW rate can still be expected in the rare patient who requires fusion as part of their treatment for LDH.

Influence of Preoperative Difference in Lumbar Lordosis Between the Standing and Supine Positions on Clinical Outcomes After Single-level Transforaminal Lumbar Interbody Fusion: Minimum 2-year Follow-up

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim of this study was to investigate whether a preoperative difference in lumbar lordosis (D-LL) between the standing and supine positions is associated with clinical outcomes after transforaminal lumbar interbody fusion (TLIF).

SUMMARY OF BACKGROUND DATA

Several factors have been reported to be associated with surgical outcomes after TLIF. However, the association between preoperative D-LL and clinical outcomes after TLIF is unknown.

METHODS

We enrolled 45 lumbar degenerative disease patients (mean age: 65.7 ± 11.3 years old; 24 males) treated with single-level TLIF. Surgical outcomes were assessed using Oswestry disability index, visual analog scale (VAS; low back pain [LBP], lower-extremity pain, numbness, LBP in motion, in standing, and in sitting), Japanese Orthopaedic Association Back Pain Evaluation Questionnaire, Japanese Orthopaedic Association score for intermittent claudication (JOA score), and Nakai's scoring system. The preoperative D-LL between the standing radiograph and computed tomography (CT) in the supine position was defined as LL in supine CT-standing radiograph. Patients were divided into two groups according to D-LL value (D-LL >-4°, and D-LL ≤-4°). Clinical outcomes were compared between the groups, and correlations between preoperative D-LL and clinical outcomes were analyzed.

RESULTS

There were no significant differences in preoperative clinical parameters between the two groups. Postoperative VASs for lower extremity pain, numbness, LBP in standing, and JOA score in D-LL >-4° group were significantly worse than in the D-LL ≤-4° group (P < 0.05). Preoperative D-LL showed a weak correlation with postoperative lower extremity pain and numbness (P < 0.05).

CONCLUSION

This study revealed that lumbar degenerative disease patients, who have greater preoperative kyphotic lumbar alignment in the standing versus supine position, tend to have postoperative residual symptoms after TLIF. A preoperative comparison of lateral radiographs between the standing and supine positions is useful to predict patients' postoperative residual symptoms.Level of Evidence: 3.

Comparative Study between Transforaminal Lumbar Interbody Fusion and Posterolateral Fusion for Treatment of Spondylolisthesis: Clinical Outcomes and Spino-Pelvic Sagittal Balance Parameters

Objective This retrospective study aims to compare the clinical and radiological outcomes of posterolateral fusion (PLF) with transforaminal lumbar interbody fusion (TLIF + PLF) for the treatment of patients with low-grade spondylolisthesis.

Methodology A total of 77 adult patients ≥18 years with low-grade spondylolisthesis, Meyerding grades I and II, were assigned into two groups: 36 patients treated with PLF and 41 patients treated with TLIF + PLF. The PLF group is composed of the patients that were operated with pedicle screw and the TLIF + PLF group is composed of the ones that were operated with fixation and TILF by autografting. Clinical evaluation was performed using the spino-pelvic sagittal balance, Numeric Rating Scale, Oswestry Disability Index, blood loss, operation times, and postoperative hospital stay of the PLF vs TLIF groups. The incidences of postoperative low back pain and radicular pain in the two groups were also recorded. Radiography was performed preoperatively and postoperatively to assess spino-pelvic parameters.

Results Significant restoration of spino-pelvic sagittal balance was observed in the TLIF group after surgery, and all spino-pelvic sagittal balance parameters showed significant improvement in the TLIF group after surgery, while in the PLF group, all spino-pelvic sagittal parameters had improved except the segmental angle lordosis (p = 0.316), which showed no significant difference after surgery in the PLF group. Postoperative pelvic incidence and pelvic tilt significantly improved in the TLIF group in comparison to PLF groups. Hence, TLIF can achieve better postoperative spino-pelvic sagittal balance parameters than PLF. There was no difference in the complication rates for each group. Both groups achieved significant improvement in postoperative clinical outcomes, and there was no significant difference in the incidence of postoperative low back pain or radicular pain between the two groups.

Conclusion Both surgical procedures PLF and TLIF were effective. PLF and TLIF can result in improved clinical and radiological outcomes for patients treated for low-grade spondylolisthesis. TLIF can achieve better restoration of spino-pelvic sagittal balance parameters than PLF alone.

Analysis of Spinopelvic Sagittal Balance and Persistent Low Back Pain (PLBP) for Degenerative Spondylolisthesis (DS) following Posterior Lumbar Interbody Fusion (PLIF)

Objective

To investigate the change of spinopelvic sagittal balance and clinical outcomes after posterior lumbar interbody fusion (PLIF) in patients with degenerative spondylolisthesis (DS), especially the relationship between sagittal spinopelvic parameters and persistent low back pain (PLBP).

Methods

107 patients who were diagnosed with DS and underwent PLIF in our department were enrolled retrospectively in the present study. Sagittal spinopelvic parameters including lumbar lordosis (LL), segmental lordosis (SL), height of the disc (HOD), sacral slope (SS), pelvic incidence (PI), and pelvic tilt (PT) were recorded pre- and postoperatively. Sagittal balance and clinical outcomes were compared between patients with and without PLBP. Pearson correlation was used to analyze the change of sagittal balance parameters and clinical functions. Logistic regression analysis was performed to examine the risk factors of PLBP.

Results

It showed significant improvements of SL, HOD, and PT postoperatively. Both the Numeric Rating Scale (NRS) and Oswestry Disability Index (ODI) had significant improvement postoperatively. Change of PT and SL also differed observably between patients with and without PLBP. SL and PT were correlated with NRS and ODI, and insufficient restoration of PT was an independent factor for PLBP.

Conclusion

The sagittal balance parameters and clinical outcomes can be improved markedly via PLIF for treating DS. Restoration of SL and PT was correlated with satisfactory outcomes, and adequate improvement of PT may have positive impact on reducing PLBP.

Reattachment of the Multifidus Tendon in Lumbar Surgery to Decrease Postoperative Back Pain: A Technical Note

The posterior midline approach to the lumbar spine requires significant manipulation of the paraspinal muscles. Muscle detachment and retraction results in iatrogenic damage such as crush injury, devascularization, and denervation, all of which have been associated with postoperative pain. The muscle most directly affected by the posterior approach is the lumbar multifidus (LM), the largest and most medial of the deep lumbar paraspinal muscles. The effects of the posterior approach on the integrity of the LM is concerning, as multiple studies have demonstrated that intraoperative injuries sustained by the LM lead to postoperative muscle atrophy and potentially worsening low back pain. Given the inevitability of intraoperative paraspinal muscle manipulation when using the posterior approach, this technical note describes methods by which surgeons may minimize LM tissue disruption and restore the anatomical position of the LM to ultimately expedite recovery, minimize postoperative pain, and improve patient satisfaction.

Risk Factors and Prevention Strategies for Postoperative Opioid Abuse

Worldwide, 80% of patients who undergo surgery receive opioid analgesics as the fundamental agent for pain relief. However, the irrational use of opioids leads to excessive drug dependence and drug abuse, resulting in an increased mortality rate and huge economic loss. The crisis of opioid overuse remains a great challenge. In this review, we summarize several key factors in opioid abuse, including race, region, income, genetic factors, age and gender, smoking and alcohol abuse, history of chronic pain and analgesic drug abuse, surgery, neuropsychiatric illness, depression and antidepressant use, human factors, national policies, hospital regulations, and health insurance under treatment of pain. Furthermore, we present several prevention strategies, such as perioperative measures, opioid substitutes, treatment of the primary illness, emotional regulation, use of opioid antagonists, efforts of the state, hospitals, doctors and pharmacy benefit managers, gene therapy, and vaccines. Greater understanding and better assessment are required of the risks associated with opioid abuse to ensure the safety and analgesic effects of pain treatment after surgery.

Biomechanical effect of bone resorption of the spinous process after single-segment interspinous dynamic stabilization device implantation: A finite element analysis

This study aims to explore the influence of bone resorption of the spinous process after single-segment interspinous process device (IPD) implantation on the biomechanics of the lumbar spine.The 3D finite element model of the lumbar spine (L3-L5) was modified, and 2 models that simulated the presence and absence of bone resorption of the spinous process were developed using an IPD (Wallis). Its biomechanical effects, such as change in range of motion (ROM) and intervertebral disc and facet stress, were introduced at operative (L4/5) and adjacent (L3/4) levels.Compared with the INT model, the Wallis model and Wallis-BR model had similar ROMs in lateral flexion and rotation. However, the Wallis model had a lower L3-5 ROM in flexion (20.4% lower) and extension (26.4% lower), and L4-L5 ROM in flexion (74.1% lower) and extension (70.8% lower), while the overall ROM of the Wallis-BR model was greater than that of the Wallis model. The stress on the L3/L4 intervertebral disc and facets was similar for all 3 models. Compared with the INT model and Wallis-BR model, the stress on the L4/L5 intervertebral disc and facets under all movements significantly decreased in the Wallis model. The stress on the L5 process was greater than that on the L4 process in both the Wallis model and Wallis-BR model, and the load on the processes that underwent bone resorption was lower than that of the Wallis model.The function of the IPD slowly decreased with the occurrence of bone resorption of the interspinous process. This bone remodeling may be associated with high stress after IPD implantation.