Diabetes Does Not Adversely Affect Neurological Recovery and Reduction of Neck Pain After Posterior Decompression Surgery for Cervical Spondylotic Myelopathy: Results From a Retrospective Multicenter Study of 675 Patients

The significance of metabolic disease in degenerative cervical myelopathy: a systematic review

Introduction

Degenerative cervical myelopathy (DCM) is a form of chronic spinal cord injury, with a natural history of potential for progression over time. Whilst driven by mechanical stress on the spinal cord from degenerative and congenital pathology, the neurological phenotype of DCM is likely to be modified by multiple systemic factors. The role of metabolic factors is therefore of interest, particularly given that ischaemia is considered a key pathological mechanism of spinal cord injury. The objective was therefore to synthesise current evidence on the effect of metabolism on DCM susceptibility, severity, and surgical outcomes.

Methods

A systematic review in MEDLINE and Embase was conducted following PRISMA guidelines. Full-text papers in English, with a focus on DCM and metabolism, including diabetes, cardiovascular disease, anaemia, and lipid profile, were eligible for inclusion. Risk of methodological bias was assessed using the Joanna Briggs Institute (JBI) critical assessment tools. Quality assessments were performed using the GRADE assessment tool. Patient demographics, metabolic factors and the relationships between metabolism and spinal cord disease, spinal column disease and post-operative outcomes were assessed.

Results

In total, 8,523 papers were identified, of which 57 met criteria for inclusion in the final analysis. A total of 91% (52/57) of included papers assessed the effects of diabetes in relation to DCM, of which 85% (44/52) reported an association with poor surgical outcomes; 42% of papers (24/57) discussed the association between cardiovascular health and DCM, of which 88% (21/24) reported a significant association. Overall, DCM patients with diabetes or cardiovascular disease experienced greater perioperative morbidity and poorer neurological recovery. They were also more likely to have comorbidities such as obesity and hyperlipidaemia.

Conclusion

Metabolic factors appear to be associated with surgical outcomes in DCM. However, evidence for a more specific role in DCM susceptibility and severity is uncertain. The pathophysiology and natural history of DCM are critical research priorities; the role of metabolism is therefore a key area for future research focus.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42021268814.

Adaptation and Limitations of painDETECT Questionnaire Score Approach Before and After Posterior Cervical Decompression Surgery

BACKGROUND

The painDETECT questionnaire (PDQ) is one of the available screening tools for neuropathic pain (NeP), with a cut-off score of 13. This study aimed to investigate changes in PDQ scores in patients undergoing posterior cervical decompression surgery for degenerative cervical myelopathy (DCM).

METHODS

Patients with DCM undergoing cervical laminoplasty or laminectomy with posterior fusion were recruited. They were asked to complete a booklet questionnaire including PDQ and Numerical Rating Scales (NRS) for pain at baseline and one year after surgery. Patients with a preoperative PDQ score ≥13 were further investigated.

RESULTS

A total of 131 patients (mean age = 70.1 years; 77 male and 54 female) were analyzed. After posterior cervical decompression surgery for DCM, mean PDQ scores decreased from 8.93 to 7.28 (P = 0.008) in all patients. Of the 35 patients (27%) with preoperative PDQ scores ≥13, mean PDQ changed from 18.83 to 12.09 (P < 0.001). Comparing the NeP improved group (17 patients with postoperative PDQ scores ≤12) with the NeP residual group (18 patients with postoperative PDQ scores ≥13), the NeP improved group showed less preoperative neck pain (2.8 vs. 4.4, P = 0.043) compared to the NeP residual group. There was no difference in the postoperative satisfaction rate between the two groups.

CONCLUSIONS

Approximately 30% of patients exhibited preoperative PDQ scores ≥13, and about half of these patients demonstrated improvements to below to the cut-off value for NeP after posterior cervical decompression surgery. The PDQ score change was relatively associated with preoperative neck pain.

Electrophysiological evidence of diabetes' impacts on central conduction recoveries in degenerative cervical myelopathy after surgery

OBJECTIVES

To assess the impact of diabetes mellitus (DM) on the postoperative motor and somatosensory functional recoveries of degenerative cervical myelopathy (DCM) patients.

METHODS

Motor and somatosensory evoked potentials (MEP and SSEPs) and modified Japanese Orthopedic Association (mJOA) scores were recorded in 27 diabetic (DCM-DM group) and 38 non-diabetic DCM patients (DCM group) before and 1 year after surgery. The central motor (CMCT) and somatosensory (CSCT) conduction time were recorded to evaluate the conductive functions of the spinal cord.

RESULTS

The mJOA scores, CMCT and CSCT improved (t test, p < 0.05) in both of the DCM-DM and DCM groups 1 year after surgery. The mJOA recovery rate (RR) and CSCT recovery ratio were significantly worse (t test, p < 0.05) in the DCM-DM group compared to the DCM group. DM proved to be a significant independent risk factor for poor CSCT recovery (OR = 4.52, 95% CI 2.32-7.12) after adjusting for possible confounding factors. In DCM-DM group, CSCT recovery ratio was also correlated with preoperative HbA1 level (R =  - 0.55, p = 0.003). Furthermore, DM duration longer than 10 years and insulin dependence were risk factors for lower mJOA, CMCT and CSCT recoveries among all DCM-DM patients (t test, p < 0.05).

CONCLUSIONS

DM may directly hinders spinal cord conduction recovery in DCM patients after surgery. Corticospinal tract impairments are similar between DCM and DCM-DM patients, but significantly worsened in chronic or insulin-dependent DM patients. The dorsal column is more sensitively affected in all DCM-DM patients. Deeper investigation into the mechanisms and neural regeneration strategies is needed.

Does Diabetes Affect the Surgical Outcomes in Cases With Cervical Ossification of the Posterior Longitudinal Ligament? A Multicenter Study From Asia Pacific Spine Study Group

STUDY DESIGN

Retrospective multicenter study.

OBJECTIVES

To evaluate the surgical outcomes of cervical ossification of the posterior longitudinal ligament (OPLL) in diabetes mellitus (DM) patients.

METHODS

Approximately 253 cervical OPLL patients who underwent surgical decompression with or without fixation were registered at 4 institutions in 3 Asian countries. They were followed up for at least 2 years. Demographics, imaging, and surgical information were collected, and cervical Japanese Orthopaedic Association (JOA) scores and the visual analog scale (VAS) for the neck were used for evaluation.

RESULTS

Forty-seven patients had DM, showing higher hypertension and cardiovascular disease prevalence. Although they presented worse preoperative JOA scores than non-DM patients (10.5 ± 3.1 vs. 11.8 ± 3.2; P = 0.01), the former showed comparable neurologic recovery at the final follow-up (13.9 ± 2.9 vs. 14.2 ± 2.6; P = 0.41). No correlation was noted between the hemoglobin A1c level in the DM group and the pre- and postoperative JOA scores. No significant difference was noted in VAS scores between the groups at pre- and postsurgery. Regarding perioperative complications, DM patients presented a higher C5 palsy frequency (14.9% vs. 5.8%; P = 0.04). A similar trend was observed when surgical procedure was limited to laminoplasty.

CONCLUSIONS

This is the first multicenter Asian study to evaluate the impact of DM on cervical OPLL patients. Surgical results were favorable even in DM cases, regardless of preoperative hemoglobin A1c levels or operative procedures. However, caution is warranted for the occurrence of C5 palsy after surgery.

Prognostic Factors Impacting Surgical Outcomes in Patients With Cervical Spondylotic Myelopathy

The purpose of surgical decompression in patients who have CSM is to stop the progression of symptoms and hopefully improve function. It is critical to understand prognostic factors that affect the outcome. Factors intrinsic to the patient that can adversely affect outcomes include diabetes, older age, tobacco use, the presence of mental health disease, and obesity. MRI imaging findings of T2 hyperintensity and clinical duration and severity of symptoms is also associated with poorer outcomes. Patients should be counseled regarding the efficacy of decompressive procedures for CSM and given realistic expectations based on their unique biophysical profiles.

Effect of diabetes on patient-reported outcome measures at one year after laminoplasty for cervical spondylotic myelopathy

Although patients with diabetes reportedly have more peripheral neuropathy, the impacts of diabetes on postoperative recovery in pain and patient-reported outcome measures (PROMs) after laminoplasty for cervical spondylotic myelopathy (CSM) is not well characterized. The authors aimed to elucidate the effects of diabetes on neck/arm/hand/leg/foot pain and PROMs after laminoplasty CSM. The authors retrospectively reviewed 339 patients (82 with diabetes and 257 without) who underwent laminoplasty between C3 and C7 in 11 hospitals during April 2017 –October 2019. Preoperative Numerical Rating Scale (NRS) scores in all five areas, the Short Form-12 Mental Component Summary, Euro quality of life 5-dimension, Neck Disability Index, and the Core Outcome Measures Index-Neck) were comparable between the groups. The between-group differences were also not significant in NRS scores and PROMs one year after surgery. The change score of NRS hand pain was larger in the diabetic group than the nondiabetic group. The diabetic group showed worse preoperative score but greater improvement in the Short Form-12 Physical Component Summary than the nondiabetic group, following comparable score one year after surgery. These data indicated that the preoperative presence of diabetes, at least, did not adversely affect pain or PROMs one year after laminoplasty for CSM.

Influence of Intervertebral Level of Stenosis on Neurological Recovery and Reduction of Neck Pain After Posterior Decompression Surgery for Cervical Spondylotic Myelopathy: A Retrospective Multicenter Study with Propensity Scoring

STUDY DESIGN

Retrospective multicenter study.

OBJECTIVE

To identify the impact of the intervertebral level of stenosis on surgical outcomes of posterior decompression for cervical spondylotic myelopathy (CSM).

SUMMARY OF BACKGROUND DATA

As the upper affected cervical levels in elderly patients result from degenerative changes in the lower cervical levels with aging, it is usually difficult to determine the influence of the upper affected cervical levels on surgical outcomes after posterior decompression for CSM in older age.

METHODS

This study involved 636 patients with CSM who underwent posterior decompression. According to the most stenotic intervertebral level, patients were divided into upper (n = 343, the most stenotic intervertebral level was C2/3, C3/4, or C4/5) and lower (n = 293, the most stenotic intervertebral level was C5/6, C6/7, or C7/T1) cervical stenosis groups. Propensity score matching of the baseline factors (characteristics, comorbidities, and neurological function) was performed to compare surgical outcomes, the Japanese Orthopaedic Association (JOA) scores, and visual analog scale (VAS) for neck pain between the upper (n = 135) and lower (n = 135) cervical stenosis groups.

RESULTS

Before propensity score matching, age at surgery was older and pre- and postoperative JOA scores were lower in the upper cervical stenosis group (P < 0.001, P < 0.001, and P < 0.001, respectively). Following matching, baseline factors were comparable between the groups. Postoperative JOA scores, preoperative-to-postoperative changes in the JOA scores, and the JOA score recovery rate were not significantly different between the groups (P = 0.866, P = 0.825, and P = 0.753, respectively). No differences existed in postoperative VAS for neck pain and preoperative-to-postoperative changes in VAS for neck pain between the groups (P = 0.092 and P = 0.242, respectively).

CONCLUSION

The intervertebral level of stenosis did not affect surgical outcomes after posterior decompression for CSM.Level of Evidence: 3.

Impact of Diabetes Mellitus on Cervical Spine Surgery for Ossification of the Posterior Longitudinal Ligament

Ossification of the posterior longitudinal ligament (OPLL) is commonly associated with diabetes mellitus (DM); however, the impact of DM on cervical spine surgery for OPLL remains unclear. This study was performed to evaluate the influence of diabetes DM on the outcomes following cervical spine surgery for OPLL. In total, 478 patients with cervical OPLL who underwent surgical treatment were prospectively recruited from April 2015 to July 2017. Functional measurements were conducted at baseline and at 6 months, 1 year, and 2 years after surgery using JOA and JOACMEQ scores. The incidence of postoperative complications was categorized into early (≤30 days) and late (>30 days), depending on the time from surgery. From the initial group of 478 patients, 402 completed the 2-year follow-up and were included in the analysis. Of the 402 patients, 127 (32%) had DM as a comorbid disease. The overall incidence of postoperative complications was significantly higher in patients with DM than in patients without DM in both the early and late postoperative periods. The patients with DM had a significantly lower JOA score and JOACMEQ scores in the domains of lower extremity function and quality of life than those without DM at the 2-year follow-up.