Dichotomizing sensory nerve fibers innervating both the lumbar vertebral body and the area surrounding the iliac crest: a possible mechanism of referred lateral back pain from lumbar vertebral body

Unilateral and Bilateral Percutaneous Vertebroplasty for Thoracolumbar Osteoporotic Vertebral Compression Fracture with Distant Lumbosacral Pain: A Single-Center Retrospective Analysis

BACKGROUND

Previous studies have found that percutaneous vertebroplasty (PVP) can effectively improve the local pain (LP) of the affected vertebra caused by thoracolumbar osteoporotic vertebral compression fracture (OVCF) regardless of unilateral or bilateral puncture, but there are few reports on whether it is equally effective for the accompanying distant lumbosacral pain. The objective of this study was to analyze the clinical efficacy of unilateral or bilateral PVP in the treatment of thoracolumbar OVCF with distant lumbosacral pain.

METHODS

The clinical data of patients with single-stage OVCF treated with PVP in our hospital from March 2019 to March 2023 were retrospectively analyzed. According to different intraoperative puncture methods, the whole cohort of patients was divided into unilateral puncture group (52 cases) and bilateral puncture group (40 cases). Preoperative, postoperative, and final follow-up were evaluated using a visual analogue scale (VAS) to assess the degree of LP in the fractured vertebrae and distant lumbosacral pain, respectively. The Oswestry Disability Index (ODI) was used to evaluate functional impairment. At the last follow-up, the proportion of patients who achieved the minimum clinical importance difference and acceptable symptom status on these measures was evaluated.

RESULTS

The average follow-up time of the 92 patients was 20.1 ± 7.6 months, and the LP, lumbosacral pain VAS score and ODI index at 3 days after surgery, and the last follow-up were significantly improved compared with those before surgery, with statistical differences (P < 0.05), but there was no statistical difference between the above indexes at 3 days after surgery and the last follow-up (P > 0.05). There were no significant differences in LP, lumbosacral pain VAS scores and ODI scores between unilateral puncture group and bilateral puncture group at different time points after surgery (P > 0.05). At the last follow-up, there were no statistically significant differences in the minimum clinical significance of LP, lumbosacral pain VAS score and ODI index and the rate of patients achieving acceptable symptom status between the two groups (P > 0.05).

CONCLUSIONS

PVP can not only improve the LP and ODI index of the responsible vertebra of OVCF in the thoracolumbar region, but also improve the accompanying distant lumbosacral pain symptoms, and the puncture approach does not affect the improvement of postoperative pain and function.

Referred pain: characteristics, possible mechanisms, and clinical management

Purpose of this review

Referred pain is a common but less understood symptom that originates from somatic tissues. A comprehensive recognition of referred pain is important for clinicians when dealing with it. The purpose of this study is to summarize the current understanding of referred pain, including its pathogenesis, characteristics, diagnosis, and treatment.

Recent findings

Referred pain arises not only from pathologies primarily involving local tissue but also from lesions in distant structures. Central sensitization of convergent neurons and peripheral reflexes of dichotomizing afferent fibers are two theories proposed to explain the pathological mechanism of referred pain. Because syndromes related to referred pain of different origins overlap each other, it is challenging to define referred pain and identify its originating lesions. Although various approaches have been used in the diagnosis and treatment of referred pain, including conservative treatment, blockade, radiofrequency, and surgery, management of referred pain remains a clinical challenge.

Summary

Unlike radicular pain and neuropathic pain, referred pain is a less studied area, despite being common in clinics. Referred pain can derive from various spinal structures, and blockage helps identify the primary pathology. Due to the heterogeneity of referred pain, treatment outcomes remain uncertain. Further studies are needed to improve our understanding of referred pain.

A Pain That is Easily Overlooked: Referred Pain Caused by OVCF

Purpose

The objective of this study was to analyze the clinical characteristics and the therapeutic effects of treatment at our spinal center in OVCF patients associated with referred pain. The underlying goals were to deepen the understanding of referred pain caused by OVCFs, improve the currently low early diagnosis rate of OVCFs, and improve the effectiveness of treatment.

Methods

The patients who had referred pain from OVCFs and met the inclusion criteria were retrospectively analyzed. All patients were treated with percutaneous kyphoplasty (PKP). Visual analog scale (VAS) scores and Oswestry Disability Index (ODI) were used to evaluate the therapeutic effect at different time points.

Results

There were 11 males (19.6%) and 45 females (80.4%). Their corresponding mean bone mineral density (BMD) value was -3.3 ± 0.4. The regression coefficient of BMD in the linear regression equation was -4.51 (P<0.001). According to the classification system for referred pain in OVCFs, there were 27 cases of type A (48.2%), 12 cases of type B (21.2%), 8 cases of type C (14.3%), 3 cases of type D (5.4%), and 6 cases of type E (10.7%). All patients were followed up for at least 6 months, and both VAS scores and ODI were found to be significantly better postoperatively than preoperatively (P<0.001). There was no significant difference in VAS scores and ODI between different types preoperatively or 6 months postoperatively (P > 0.05). Within each type, there were significant differences in VAS scores and ODI between the pre- and postoperative timepoints (P < 0.05).

Conclusion

Attention should be paid to referred pain in OVCF patients, which is not uncommon in clinical practice. Our summary of the characteristics of referred pain caused by OVCFs can improve the early diagnosis rate of OVCFs patients and provide a reference for their prognosis after PKP.