Reliability and validity of the Neck Disability Index among patients undergoing cervical surgery

Psychometric evaluation of the Japanese neck disability index by exploratory factor analysis in preoperative patients with cervical spondylotic myelopathy: impact of pain and numbness

BACKGROUND CONTEXT

The Neck Disability Index (NDI), a common Patient-Reported Outcome Measure (PROM) for neck pain, lacks sufficient study on its psychometric properties in preoperative patients with cervical spondylotic myelopathy (CSM).

PURPOSE

This study aims to address these gaps by conducting an exploratory factor analysis of the Japanese NDI. The objectives are 2-fold: (1) to scrutinize the psychometric properties and internal consistency of the Japanese NDI, and (2) to explore the specific regions of pain and numbness influencing the NDI.

STUDY DESIGN/SETTING

A single-center observational study.

PATIENT SAMPLE

A total of 100 preoperative patients with CSM.

OUTCOME MEASURES

The NDI and Numerical Rating Scale (NRS) were employed to assess preoperative neck disability and pain and numbness in various body regions.

METHODS

Demographic and clinical characteristics were collected, encompassing age, sex, body mass index, American Society of Anesthesiologists classification, smoking status, comorbidities, pain and numbness at various sites using the NRS, and NDI. For evaluating the psychometric properties and internal consistency of the NDI, exploratory factor analysis (EFA) and Cronbach's α coefficient were utilized. Furthermore, the impact of pain and numbness on NDI factors was examined through multivariable regression analysis.

RESULTS

EFA identified 2 factors-Physical and Mental-highlighting the dual nature of neck-related disability. Physical factors (std.β=0.724, p<.001) exerted a stronger impact on NDI scores compared to Mental factors (std.β=0.409, p<.001). Cronbach's α coefficient was 0.831 for physical factors and 0.723 for mental factors, indicating a high level of internal consistency. Numbness in the hand (std.β=0.338, p<.001) and pain in the neck (std.β=0.202, p=.035) were significant variables influencing Physical factor, while numbness in the hand (std.β=0.485, p<.001) and pain in the head (std.β=0.374, p<.001) impacted Mental factor.

CONCLUSION

This study contributes valuable insights into the psychometric properties of the NDI in preoperative patients with CSM. The identified factors emphasize the importance of addressing both physical and sensory symptoms in preoperative care.

Safety and Efficacy of Zero-Profile Polyetheretherketone (PEEK) Cages Filled with Biphasic Calcium Phosphate (BCP) in Anterior Cervical Discectomy and Fusion (ACDF): A Case Series

Background: In the evolving landscape of anterior cervical discectomy and fusion (ACDF), the integration of biomechanical advancements and proper fusion-enhancing materials is crucial for optimizing patient outcomes. This case series evaluates the efficacy and clinical implications of employing zero-profile polyetheretherketone (PEEK) cages filled with biphasic calcium phosphate (BCP) in ACDF procedures, focusing on fusion and subsidence rates alongside patient disability, residual pain, and quality of life. Methods: This case series comprises 76 consecutive patients, with a median follow-up of 581 days. The Bridwell classification system was used for assessing fusion rates while subsidence occurrence was recorded, correlating these radiographic outcomes with clinical implications. Results: The results demonstrated a satisfactory fusion rate (76.4% for grades I and II). The subsidence rate was low (6.74% of segments). Significant clinical improvements were observed in pain, disability, and quality-of-life metrics, aligning with the minimum clinically important difference thresholds; however, subgroup analyses demonstrated that subsidence or pseudoarthrosis group improvement of PROMs was not statistically significant with respect to baseline. ANOVA analyses documented that subsidence has a significant weight over final follow-up pain and disability outcomes. No dysphagia cases were reported. Conclusions: These findings underscore the efficacy of zero-profile PEEK cages filled with BCP in ACDF, highlighting their potential to improve patient outcomes while minimizing complications. Pseudoarthrosis and subsidence have major implications over long-term PROMs. The study reinforces the importance of selecting appropriate surgical materials to enhance the success of ACDF procedures.

The Subjective and Objective Improvement Using Chiropractic Biophysics® Protocols

The aim of this study is to describe the Chiropractic BioPhysics® (CBP®) (Chiropractic BioPhysics, Eagle, USA) technique in alleviating the persistent spine pain syndrome (PSPS) and dysfunction in a 50-year-old female who suffered for many years. The purpose of this study is to provide clinicians with a potential treatment option for failed back surgery syndrome (FBSS) and PSPS that doesn't respond to other treatments. The patient did not receive benefits from pharmaceutical and conservative therapies following a low back lifting injury in 2004. After several years of suffering from widespread spinal pain and dysfunction, she received a lumbosacral pedicle screw surgical fixation. The initial surgery was unsuccessful and a follow-up revision and expansion of the fusion failed to alleviate the pain and dysfunction as well. After treatment using CBP, the patient received subjective, objective, and radiographic improvements with long-term stability measured at follow-up. Given that spine pain and low back pain are the number one cause of disability in the world, having economical, repeatable, and measurable techniques to improve even difficult cases is important for astute clinicians treating spine pain.

Poor patient-reported mental health correlates with inferior patient-reported outcome measures following cervical disc replacement

PURPOSE

This study aims to assess the correlation between the patient-reported mental health and the self-reported outcome measures (PROMs) physical function, pain, and disability at different time points following disc replacement (CDR).

METHODS

A single-surgeon registry was searched for patients who had undergone CDR, excluding those with indication for infection, cancer, or trauma. One hundred fifty-one patients were included. PROMs were collected preoperatively as well as 6 weeks, 3 months, 6 months, and 1 year postoperatively. Mental health measures evaluated included 12-Item Short Form (SF-12), Mental Component Score (MCS), and Patient Health Questionnaire-9 (PHQ-9) which were individually assessed via Pearson's correlation tests in relation to Patient-Reported Outcome Measurement Information System Physical Function (PROMIS-PF), SF-12 Physical Component Score (PCS), visual analog scale (VAS) neck and arm pain, and Neck Disability Index (NDI).

RESULTS

SF-12 MCS positively correlated with PROMIS-PF (range: r = 0.369-0.614) and SF-12 PCS (range: r = 0.208-0.585) with significance found at two or more time points for each (p ≤ 0.009, all). SF-12 MCS negatively correlated with VAS neck (range: r = - 0.259 to - 0.464), VAS arm (range: r = - 0.281 to - 0.567), and NDI (range: r = - 0.474 to - 831) with significance found at three or more time points (p ≤ 0.028, all). PHQ-9 significantly negatively correlated with PROMIS-PF (range: r = - 0.457 to - 0.732) and SF-12 PCS (range: r = - 0.332 to - 0.629) at all time points (p ≤ 0.013, all). PHQ-9 positively correlated with VAS neck (range: r = 0.351-0.711), VAS arm (range: r = 0.239-0.572), and NDI (range: r = 0.602-0.837) at four or more periods (p ≤ 0.032, all).

CONCLUSION

Patients undergoing CDR who reported lower mental health scores via either SF-12 MCS or PHQ-9 were associated with increased perception of pain and disability. Disability level correlated with mental health at all time periods. Patients with optimized mental health may report higher outcome scores following CDR.

Importance of factors determining disability caused by neck pain may vary by gender and age

The objective was to investigate if age and gender affect the importance of domains of functioning when grading disability related to neck pain. Multi-group confirmatory factor analysis of register-based data on 392 patients undergoing cervical surgery was applied. The main outcome was item loadings on a common factor. The mean age was 55 years and 52% were women. The factor structure was different for both gender and age groups, P  < 0.0001. Reading, driving, pain intensity, and recreational activity had the highest loadings while headaches, lifting, and sleep placed the lowest. Reading and pain intensity had bigger weight among men than women, while recreational activity and driving had higher loadings in women. Reading and work were more important for the younger than for the older respondents, while recreational activity was more important for the older respondents. The importance of factors determining disability caused by neck pain may vary by gender and age.