Is Lumbar Fusion Necessary for Chronic Low Back Pain Associated with Degenerative Disk Disease? A Meta-Analysis

Development of a patient decision aid for people with chronic low back pain and degenerative disc disease considering lumbar fusion: A mixed-methods study

OBJECTIVES

To develop and user-test a patient decision aid providing evidence-based information for people with chronic low back pain (LBP) and degenerative disc disease considering lumbar fusion.

DESIGN

Convergent parallel mixed methods study.

SETTING

A prototype patient decision aid was developed, guided by the International Patient Decision Aid Standards (IPDAS) criteria, a multidisciplinary steering committee, and insights from previous studies. Participants were recruited via social media and the authors' collaborative networks to refine and evaluate the decision aid.

PARTICIPANTS

Individuals who underwent lumbar fusion for chronic LBP and health professionals who manage these patients were purposively sampled.

PRIMARY AND SECONDARY OUTCOMES

Semi-structured interviews and questionnaires were used to gather feedback and assess the decision aid's acceptability, usability, and preparedness for decision-making. Framework analysis was used for interview data and descriptive analysis for questionnaires.

RESULTS

Sixteen clinicians (5 physiotherapists, 2 rheumatologists, 2 surgeons, 7 general practitioners) and seven patients participated, most rating the prototype's acceptability as 'excellent' or 'good'. Usability (mean [SD], health professionals: 78 [16], patients: 72 [8]) and preparedness for decision-making (health professionals: 73 [14], patients: 72 [10]) also scored highly. However, some viewed the prototype as biased against lumbar fusion, and suggestions to include more personalised information were made.

CONCLUSIONS

This study showed that our prototype patient decision aid is acceptable, useful, and prepares patients to make informed decisions about spinal fusion for chronic LBP and degenerative disc disease. Future studies will assess the clinical impact of our decision aid and its optimal distribution timing.

Healthcare Professionals' Decision-Making Regarding Lumbar Fusion Surgery or Conservative Care for Adults With Severe, Persistent Low Back Pain: An Australian Cross-Sectional Survey Using Case Vignettes

STUDY DESIGN

Cross-sectional Survey.

OBJECTIVES

The objective of this study was to describe clinicians' decision-making regarding suitability of patient cases for lumbar fusion surgery or conservative care and the level of equipoise to randomise participants into a randomised controlled trial (RCT).

METHODS

An online survey distributed via Australian professional networks to clinicians involved in low back pain care, collected data on clinical discipline, clinical experience, practice setting and preferred care of five patient case vignettes (ranging in age, pain duration, BMI, imaging findings, neurological signs/symptoms). Clinicians were asked about preferred clinical care and willingness to randomise each case.

RESULTS

Of 101 respondents (31 orthopaedic surgeons, 17 neurosurgeons, 50 allied health professionals (AHPs), 1 pain physician, 1 nurse), 44% worked in public health services only, 36.4% in both public and private, 19.2% in private only. 46.5% had over 20 years clinical experience. Conservative care was preferred for all cases (83.1%-90.9%). Surgeons preferred an anterior approach to lumbar fusion (range 40.6%-68.4%). On average 51.9% (range: 47%-55%) indicated willingness to randomise cases, with orthopaedic (61.5%) and neurosurgeons (64.9%) more willing than AHPs (44.4%). Willingness to randomise was highest in younger cases with shorter pain duration, no neurological symptoms/signs and localised degeneration, and lowest when cases had high BMI, longer pain duration, and inadequate conservative management. Willingness to randomise was higher in those in private (70.3%) vs public health care services (43.6%).

CONCLUSIONS

Over half of respondents reported willingness to randomise cases, indicating sufficient clinical equipoise for a future RCT.

Which Kind of Prognosis is Better in the Treatment of Cervical and Lumbar Disc Herniation with Coblation Nucleoplasty?

Introduction

Coblation nucleoplasty is a minimally invasive procedure developed for the treatment of symptomatic disc herniation.

Methods

We evaluated 118 cases of cervical and lumbar intervertebral discs treated with coblation nucleoplasty. The clinical results were assessed using the visual analogue scale (VAS), modified MacNab criteria, and efficacy. Complications and the re-surgery rate were also evaluated. The procedure was carried out under CT guidance, and the patients were followed up for 1 day, 1 month, 6 months, and 5 years postoperative.

Results

At the 5-year follow-up, the VAS score in the cervical and lumbar groups significantly decreased from 6.20 to 2.43 and 6.11 to 3.29, respectively. While MacNab scores were indistinguishable at the 6-month follow-up, they differed significantly between the cervical (58.2%) and lumbar (34.9%) groups at the 5-year follow-up. At the 5-year follow-up, 6 patients in the cervical group and 11 in the lumbar group underwent conventional operation. The efficacy of coblation nucleoplasty at the 5-year follow-up was higher in cervical group (81.82%) compared with lumbar group (61.90%).

Conclusion

The results of this study suggest that coblation nucleoplasty is a safe and effective treatment option for patients with cervical and lumbar disc herniation. The long-term benefits of this procedure were more pronounced in patients with cervical disc herniation.

Clinical Trial Registration

The trial was registered on ClinicalTrials.gov (ChiCTR2400089145).

Biologic Therapies for Discogenic Pain

PURPOSE OF REVIEW

The purpose of this review is to provide an update on recent developments in the field of regenerative medicine, specifically focusing on emerging data related to biologics, including platelet-rich plasma and mesenchymal cells, for the treatment of discogenic back pain.

RECENT FINDINGS

There has been a notable surge of interest in biologics, as evidenced by a wealth of recent reviews and studies. While serious adverse events are generally uncommon, considerable heterogeneity exists in study designs. More robust investigations are warranted to thoroughly evaluate the safety and efficacy of biologics in treating discogenic back pain. Continued research and funding are needed to better understand the underlying mechanisms of disc degeneration and to develop targeted therapies that can alleviate and reduce the burden of this debilitating condition. Biologics may offer effective treatments for discogenic pain; however, more multi-center, prospective, double-blinded, randomized placebo-controlled trials are essential to further establish their effectiveness.

Lumbar spine fusion surgery versus best conservative care for patients with severe, persistent low back pain

Aims

People with severe, persistent low back pain (LBP) may be offered lumbar spine fusion surgery if they have had insufficient benefit from recommended non-surgical treatments. However, National Institute for Health and Care Excellence (NICE) 2016 guidelines recommended not offering spinal fusion surgery for adults with LBP, except as part of a randomized clinical trial. This survey aims to describe UK clinicians' views about the suitability of patients for such a future trial, along with their views regarding equipoise for randomizing patients in a future clinical trial comparing lumbar spine fusion surgery to best conservative care (BCC; the FORENSIC-UK trial).

Methods

An online cross-sectional survey was piloted by the multidisciplinary research team, then shared with clinical professional groups in the UK who are involved in the management of adults with severe, persistent LBP. The survey had seven sections that covered the demographic details of the clinician, five hypothetical case vignettes of patients with varying presentations, a series of questions regarding the preferred management, and whether or not each clinician would be willing to recruit the example patients into future clinical trials.

Results

There were 72 respondents, with a response rate of 9.0%. They comprised 39 orthopaedic spine surgeons, 17 neurosurgeons, one pain specialist, and 15 allied health professionals. Most respondents (n = 61,84.7%) chose conservative care as their first-choice management option for all five case vignettes. Over 50% of respondents reported willingness to randomize three of the five cases to either surgery or BCC, indicating a willingness to participate in the future randomized trial. From the respondents, transforaminal interbody fusion was the preferred approach for spinal fusion (n = 19, 36.4%), and the preferred method of BCC was a combined programme of physical and psychological therapy (n = 35, 48.5%).

Conclusion

This survey demonstrates that there is uncertainty about the role of lumbar spine fusion surgery and BCC for a range of example patients with severe, persistent LBP in the UK.

Failed back surgery syndrome-terminology, etiology, prevention, evaluation, and management: a narrative review

Amid the worldwide increase in spinal surgery rates, a significant proportion of patients continue to experience refractory chronic pain, resulting in reduced quality of life and escalated healthcare demands. Failed back surgery syndrome (FBSS) is a clinical condition characterized by persistent or recurrent pain after one or more spinal surgeries. The diverse characteristics and stigmatizing descriptions of FBSS necessitate a reevaluation of its nomenclature to reflect its complexity more accurately. Accurate identification of the cause of FBSS is hampered by the complex nature of the syndrome and limitations of current diagnostic labels. Management requires a multidisciplinary approach that may include pharmacological treatment, physical therapy, psychological support, and interventional procedures, emphasizing realistic goal-setting and patient education. Further research is needed to increase our understanding, improve diagnostic accuracy, and develop more effective management strategies.

An evaluation of the effectiveness of platelet rich plasma epidural injections for low back pain suspected to be of disc origin - A pilot study with one-year follow-up

Summary of background data

Low back pain of disc origin is common yet challenging to treat. Intradiscal platelet rich plasma (PRP) has been advocated, but is associated with risk of discitis. Epidural PRP is less invasive and avoids this risk. Few studies exist evaluating effectiveness and safety of epidural PRP for discogenic low back pain without radiculopathy and the follow-up of the studies tends to be short.

Objective

Prospectively evaluate for 12 months the effectiveness of PRP epidural injections for patients with low back pain without radiculopathy, suspected to be of disc origin.

Methods

11 consecutive patients with refractory low back pain suspected to be of disc origin (compatible clinical assessment; negative lumbosacral medial branch blocks (MBBs) and/or magnetic resonance imaging (MRI) with high intensity zone (HIZ), Modic 1 or 2 changes) participated. Each underwent one (n = 5) or two (n = 6) epidural injections (caudal or interlaminar). The PRP was leukocyte/red cell depleted with an average platelet concentration of ∼2X whole blood. Numerical rating scale (NRS), Pain Disability Quality-Of-Life Questionnaire (PDQQ) score, Oswestry Disability Index (ODI) score, effect on analgesic intake, treatment satisfaction and endorsement were recorded prior to and at 3, 6 and 12-months post-treatment.

Results

Significant improvements in pain and disability were documented post-treatment. Pre-, 3, 6, and 12-month post mean(sd) NRS scores were 7.8(1.8), 5.8(2.7), 5.1(2.5), 4.9(2.8) respectively (F = 7.2; p = 0.002). At 12 months post PRP epidural, the mean improvement in NRS was 36%, 36% had experienced ≥50% pain relief (95% confidence interval (CI): 2%, 70%), and 73% achieved minimal clinically important differences (MCID) (95% CI: 41%, 100%). Similar magnitude improvements in disability (PDQQ and ODI) were documented. At 1-year post, 50% of analgesic users had reduced intake, 91% were satisfied with the treatment and would recommend the procedure to family and friends. No complications were reported.

Discussions/conclusion

This pilot project suggests that PRP epidural injections provide modest yet significant improvements in pain and disability that lasts at least 12 months in patients with low back pain suspected to be of disc origin. Additional research including larger sample size and robust study design is encouraged.

Pacific Spine and Pain Society (PSPS) Evidence Review of Surgical Treatments for Lumbar Degenerative Spinal Disease: A Narrative Review

INTRODUCTION

Interventional treatment options for the lumbar degenerative spine have undergone a significant amount of innovation over the last decade. As new technologies emerge, along with the surgical specialty expansion, there is no manuscript that utilizes a review of surgical treatments with evidence rankings from multiple specialties, namely, the interventional pain and spine communities. Through the Pacific Spine and Pain Society (PSPS), the purpose of this manuscript is to provide a balanced evidence review of available surgical treatments.

METHODS

The PSPS Research Committee created a working group that performed a comprehensive literature search on available surgical technologies for the treatment of the degenerative spine, utilizing the ranking assessment based on USPSTF (United States Preventative Services Taskforce) and NASS (North American Spine Society) criteria.

RESULTS

The surgical treatments were separated based on disease process, including treatments for degenerative disc disease, spondylolisthesis, and spinal stenosis.

CONCLUSIONS

There is emerging and significant evidence to support multiple approaches to treat the symptomatic lumbar degenerative spine. As new technologies become available, training, education, credentialing, and peer review are essential for optimizing patient safety and successful outcomes.

Lumbar Epidural Hematoma as a Rare Complication From Minimally Invasive Lumbar Decompression

Lumbar spinal stenosis (LSS) is a common and debilitating pathology globally. Conservative and surgical treatment options exist for patients. Recently, minimally invasive lumbar decompression (MILD) has been described as a less invasive technique for the treatment of early spinal stenosis ≥2.5mm ligamentum thickening or in patients at high risk for general anesthesia. Often, MILD is performed by interventional pain providers and shows low complication rates. We describe a 76-year-old woman who presented to the emergency department immediately after undergoing a MILD procedure at an outside surgery center with lower back/sacral pain resulting from an acute epidural hematoma extending from T12-L3. Early recognition and surgical evacuation resulted in a good outcome with no complications. Our goal is to increase awareness of this rare complication and encourage multidisciplinary approaches to managing LSS between spine surgeons and pain providers.

Treatment of Refractory Low Back Pain Using Passive Recharge Burst in Patients Without Options for Corrective Surgery: Findings and Results From the DISTINCT Study, a Prospective Randomized Multicenter Controlled Trial

OBJECTIVE

Spinal cord stimulation (SCS) is effective for relieving chronic intractable pain conditions. The Dorsal spInal cord STImulatioN vs mediCal management for the Treatment of low back pain study evaluates the effectiveness of SCS compared with conventional medical management (CMM) in the treatment of chronic low back pain in patients who had not undergone and were not candidates for lumbar spine surgery.

METHODS AND MATERIALS

Patients were randomized to passive recharge burst therapy (n = 162) or CMM (n = 107). They reported severe pain and disability for more than a decade and had failed a multitude of therapies. Common diagnoses included degenerative disc disease, spondylosis, stenosis, and scoliosis-yet not to a degree amenable to surgery. The six-month primary end point compared responder rates, defined by a 50% reduction in pain. Hierarchical analyses of seven secondary end points were performed in the following order: composite responder rate (numerical rating scale [NRS] or Oswestry Disability Index [ODI]), NRS, ODI, Pain Catastrophizing Scale responder rate, Patient Global Impression of Change (PGIC) responder rate, and Patient-Reported Outcome Measure Information System-29 in pain interference and physical function.

RESULTS

Intention-to-treat analysis showed a significant difference in pain responders on NRS between SCS (72.6%) and CMM (7.1%) arms (p < 0.0001). Of note, 85.2% of those who received six months of therapy responded on NRS compared with 6.2% of those with CMM (p < 0.0001). All secondary end points indicated the superiority of burst therapy over CMM. A composite measure on function or pain relief showed 91% of subjects with SCS improved, compared with 16% of subjects with CMM. A substantial improvement of 30 points was observed on ODI compared with a

CONCLUSIONS

This study found substantial improvement at six months in back pain, back pain-related disability, pain-related emotional suffering, PGIC, pain interference, and physical function in a population with severe, debilitating back pain for more than a decade. These improvements were reported in conjunction with reduced opioid use, injection, and ablation therapy.

CLINICAL TRIAL REGISTRATION

The Clinicaltrials.gov registration number for the study is NCT04479787.

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Key Words

• composite outcomes
• persistent spinal pain syndrome
• refractory chronic low back pain
• spinal cord stimulation

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MESH Headings

• Humans
• Low Back Pain/therapy
• Low Back Pain/psychology
• Treatment Outcome
• Prospective Studies
• Back Pain
• Spinal Cord Stimulation/methods
• Chronic Pain/diagnosis
• Chronic Pain/therapy

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Grants

• K08 CA228039 NCI NIH HHS

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Affiliation(s)

Timothy Deer The Spine and Nerve Center of the Virginias, Charleston, WV, USA
Christopher Gilligan Brigham & Women's Hospital, Boston, MA, USA
Steven Falowski Center for Interventional Pain & Spine, Lancaster, PA, USA
Mehul Desai International Spine, Pain & Performance Center, Washington, DC, USA
Julie Pilitsis Florida Atlantic University, FL, USA
Jessica Jameson Axis Spine Center, ID, USA
Susan Moeschler Mayo Clinic, Rochester, NY, USA
Robert Heros Spinal Diagnostics, OR, USA
Edward Tavel Clinical Trials of South Carolina, Charleston, SC, USA
Anne Christopher Saint Louis Pain Consultants, Chesterfield, MO, USA
Denis Patterson Nevada Advanced Pain Specialists, Reno, NV, USA
Sayed Wahezi Montefiore Medical Center-Waters Place, New York, NY, USA
Jacqueline Weisbein Napa Valley Orthopedic Medical Group, Napa, CA, USA
Ajay Antony The Orthopaedic Institute, FL, USA
Robert Funk Indiana Spine Group, IN, USA
Mohab Ibrahim Banner University Medical Center Tucson Campus, Tucson, AZ, USA
Chi Lim Carolina Orthopaedic & Neurosurgical Associates, SC, USA
Derron Wilson Goodman Campbell Brain & Spine, IN, USA
Michael Fishell Advanced Pain Care, NV, USA
Keith Scarfo Rhode Island Hospital, Providence, RI, USA
David Dickerson Northshore University HealthSystem, Chicago, IL, USA
Edward Braun Kansas University Medical Center, KS, USA
Patrick Buchanan Spanish Hills Interventional Pain Specialists, Camarillo, CA, USA
Robert M Levy Anesthesia Pain Care Consultants-Tamarac
Nathan Miller Coastal Pain & Spinal Diagnostics Medical Group, Carlsbad, CA, USA
Jonathan Duncan Burkhart Research Institute for Orthopaedics, San Antonio, TX, USA
Jijun Xu The Cleveland Clinic Foundation, OH, USA
Kenneth Candido Chicago Anesthesia Associates, SC, Chicago, IL, USA
Scott Kreiner Barrow Brain & Spine-Ahwatukee, Phoenix, AZ, USA
Marie E Fahey Abbott Labs, Austin, TX, USA
James Yue Connecticut Orthopaedics, CT, USA

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Review: Discogenic Back Pain: Update on Treatment

Purpose of Review

Lower back pain (LBP) has a lifetime prevalence of 80% in the United States population. Discogenic back pain (DBP), a subcategory of LBP, occurs as a result of the interverbal disc degeneration without disc herniation. Diagnosis relies on history, physical exam, and imaging such as MRI, provocative discography, or CT discography.

Recent Findings

Treatment of DBP involves a multifaceted approach with an emphasis on conservative measures including behavioral modification, pharmacologic management, and other non-pharmacologic interventions with invasive therapy reserved for select patients. Due to the paucity of data on the treatment of DBP, treatment also relies on data derived from treatment of chronic LBP (CLBP).

Summary

Despite the scarcity of data for the treatment of DBP, treatments do exist with varying efficacy for DBP. Novel techniques such as the use of biologics may provide another avenue for treatment though further studies are needed to better evaluate the most efficacious regimen for both novel and existing treatments.

Clinical Outcomes of Bariatric Surgery Before Spinal Fusion: A Systematic Review

INTRODUCTION

Morbidly obese patients are at increased risk for intraoperative and postoperative complications following spinal fusion. Preoperative weight loss can improve clinical outcomes. The present systematic literature review is aimed to evaluate the hypothesis that bariatric surgery before spinal fusion surgery is associated with higher rates of complications and revisions.

METHODS

Three databases were queried for literature pertaining to bariatric surgery prior to spinal fusion. A 2-author screening process was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Methodologic index for non-randomized studies criteria was used to objectively assess the methodologic quality of the studies reviewed. Retrospective cohort studies in which the patients underwent bariatric surgery were included.

RESULTS

Four retrospective cohort studies consisting of a total of 180,090 patients were included. Length of stay was significantly shorter for the bariatric surgery (BS) group patients than the control (C) groups patients (P = 0.009). There were no significant differences in 1-year mortality rate (P = 1.0), readmission rate (P = 0.86), overall postoperative complications (P = 0.83), and postoperative infections (P = 0.97) between the BS and C groups.

CONCLUSIONS

There were no consistent differences in rates of postoperative complications, infections, hospital readmission, and mortality between obese patients with bariatric surgery prior to spinal fusion and control group patients. The present study does not support the hypothesis that bariatric surgery before spinal fusion contributes to a higher rate of postoperative complications in patients undergoing spinal fusion.

The impact of physical and psychological pain management training on pain intensity, anxiety and disability in patients undergoing lumbar surgeries

BACKGROUND/CONTEXT

Lumbar surgery is one of the interventions performed for patients with degenerative conditions.

PURPOSE

This study aimed to investigate the effect of pain management education on pain intensity, anxiety, and disability after the lumbar surgery.

STUDY DESIGN/SETTING

This randomized controlled trial was performed on seventy 30 to 65-year-old patients with lumbar canal stenosis and lumbar disc herniation from 2018 to 2019.

PATIENT SAMPLE

Seventy participants were randomly divided into a control and an intervention group by a randomized block design. Participants in the intervention group received in-person pain management training twice a week for seven 60 to 90-minute sessions.

OUTCOME MEASURES

All participants in the two groups completed the study instruments (numeric rating scale [NRS], Oswestery disability index [ODI], and pain anxiety symptoms scale [PASS]) before, immediately after, and 3 months after the study.

METHODS

Participants in the intervention group received in-person pain management training twice a week for seven 60 to 90-minute sessions. To analyze the treatment effects, repeated-measures multivariate analysis of variance (MANOVA) and effect sizes were used where appropriate and calculated by Partial ɳ². Clinical outcome (MDC) for pain intensity and PASS was also reported. For participants lost to follow-up, we also used an "intention-to-treat" (ITT) approach.

RESULTS

The results of MANOVA indicated that there were significant differences between the two groups on ratings of pain intensity, anxiety, and disability. According to the MDC, the mean differences of pain intensity for the intervention group was also clinically improved. Meanwhile, the mean differences in pain anxiety between three different times in the two groups were not above the MDC (20.14), suggesting that the clinical improvements were not significant. The results were confirmed for all outcome measures; a statistically significant difference was found between the groups in ITT analyses (p<.001).

CONCLUSIONS

Physical and psychological pain management education was shown to be effective in decreasing pain intensity, anxiety, and disability. This strategy may be beneficial for such patients. Variables such as smoking behavior, past history of psychological disorders, and previous surgeries should be considered in future studies.

Bone morphogenic protein-2 signaling in human disc degeneration and correlation to the Pfirrmann MRI grading system

BACKGROUND CONTEXT

Back and neck pain secondary to disc degeneration is a major public health burden. There is a need for therapeutic treatments to restore intervertebral disc (IVD) composition and function.

PURPOSE

To quantify ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens collected from patients undergoing surgery for disc degeneration, to correlate ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens to the 5-level Pfirrmann MRI grading system, and to compare ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression between cervical and lumbar degenerative disc specimens.

STUDY DESIGN

An immunohistochemical study assessing ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in human control and degenerative IVD specimens.

METHODS

Human IVD specimens were collected from surgical patients who underwent discectomy and interbody fusion at our institution between 1/2015 and 8/2017. Each patient underwent MRI prior to surgery. The degree of disc degeneration was measured according to the 5-level Pfirrmann MRI grading system. Patients were categorized into either the 1) control group (Pfirrmann grades I-II) or 2) degenerative group (Pfirrmann grades III-V). Histology slides of the collected IVD specimens were prepared and immunohistochemical staining was performed to assess ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in the control and degenerative specimens. Expression levels were also correlated to the Pfirrmann criteria. Lastly, the degenerative specimens were stratified according to their vertebral level and expression levels between the degenerative lumbar and cervical discs were compared.

RESULTS

Fifty-two patients were enrolled; however, 2 control and 2 degenerative patients were excluded due to incomplete data sets. Of the remaining 48 patients, there were 12 control and 36 degenerative specimens. Degenerative specimens had increased expression levels of BMP-2 (p=.0006) and pSMAD1/5/8 (p<.0001). Pfirrmann grade 3 (p=.0365) and grade 4 (p=.0008) discs had significantly higher BMP-2 expression as compared to grade 2 discs. Pfirrmann grade 4 discs had higher pSMAD1/5/8 expression as compared to grade 2 discs (p<.0001). There were no differences in ALK3 or MMP-13 expression between the control and degenerative discs (p>.05). Stratifying the degenerative specimens according to their vertebral level showed no significant differences in expression levels between the lumbar and cervical discs (p>.05).

CONCLUSIONS

BMP-2 and pSMAD1/5/8 signaling activity was significantly upregulated in the human degenerative specimens, while ALK3 and MMP-13 expression were not significantly changed. The expression levels of BMP-2 and pSMAD1/5/8 correlate positively with the degree of disc degeneration measured according to the Pfirrmann MRI grading system.

CLINICAL SIGNIFICANCE

BMP-SMAD signaling represents a promising therapeutic target to restore IVD composition and function in the setting of disc degeneration.