Chapman Kenneth B, Tupper Connor, Vissers Kris C, van Helmond Noud, Yousef Tariq
Spine & Pain Institute of New York, New York, New York, USA.
Department of Anesthesiology, New York University Langone Medical Center, New York, New York, USA.
Pain Pract. 2023 Mar;23(3):317-324. doi: 10.1111/papr.13180. Epub 2022 Dec 8.
Dorsal root ganglion stimulation (DRG-S) has recently emerged as a novel therapy in neuromodulation that demonstrated a higher rate of success than spinal cord stimulation (SCS) in a prospective, head-to-head randomized comparative trial to treat complex regional pain syndrome (CRPS) and causalgia. In contrast to SCS, DRG-S also shows promise in treating conditions that are not purely neuropathic such as axial low back pain, which has a prominent nociplastic pain component. It is not known to what extent the effectiveness of DRG-S for such indications is due to effective treatment of the neuropathic pain component versus the effects of DRG-S on mechanical pain. Although rarely studied, reporting outcomes of DRG-S to treat predominantly mechanical/nociceptive pain may help point toward expanding the utility of this therapy. Here, we present five cases of refractory mechanical pain treated with DRG-S.
A retrospective analysis of all patients who underwent a successful DRG-S trial and implant between September 2017 and September 2021 at our institute was performed. Patients who had intractable joint pain without strong evidence of neuropathic pain were included in this case series. The Budapest criteria for CRPS, the Douleur Neuropathique 4 Questions (DN4) survey, or a definable nerve injury were used to determine the presence of neuropathic pain. Baseline assessments for pain (Numeric Rating Scale [NRS]), function (Oswestry Disability Index [ODI]), quality of life (EuroQol-5 Dimension [EQ-5D]), and other applicable joint surveys were extracted from pre-trial baseline and follow-up appointments.
Five patients were identified and included. Patient diagnoses consisted of refractory joint pain of the hip, knee, or ankle. Mean NRS pain scores improved by 74% from 9.2 at baseline to 2.4 at the last follow-up (mean = 28 months post-implant). From baseline to the last follow-up, mean ODI scores improved by 65% from 66 to 23 and EQ-5D scores more than doubled from an average of 0.371 to 0.797.
This clinical report illustrates the potential utility DRG-S has in treating pain that clinically presents as predominantly refractory mechanical joint pain without a significant neuropathic component. The physiological reasons for our observations may be that DRG-S is able to directly influence the conduction of nociceptive signaling at the DRG and within the spinal cord. Further investigations are warranted to determine if DRG-S is a potential treatment option for chronic mechanical pain.
背根神经节刺激术（DRG-S）最近已成为神经调节领域的一种新型疗法，在一项前瞻性、直接对比的随机对照试验中，该疗法治疗复杂性区域疼痛综合征（CRPS）和灼性神经痛的成功率高于脊髓刺激术（SCS）。与SCS不同，DRG-S在治疗并非单纯神经性疼痛的疾病方面也显示出前景，比如具有明显的伤害性感受性疼痛成分的轴性下腰痛。目前尚不清楚DRG-S对这些适应症的有效性在多大程度上归因于对神经性疼痛成分的有效治疗，还是归因于DRG-S对机械性疼痛的影响。尽管很少有研究，但报告DRG-S治疗以机械性/伤害性疼痛为主的结果可能有助于指出扩大该疗法应用范围的方向。在此，我们介绍5例接受DRG-S治疗的难治性机械性疼痛病例。
对2017年9月至2021年9月在我院成功进行DRG-S试验并植入装置的所有患者进行回顾性分析。本病例系列纳入了患有顽固性关节疼痛且无强有力的神经性疼痛证据的患者。采用CRPS的布达佩斯标准、神经病理性疼痛4项问题（DN4）调查问卷或可明确的神经损伤来确定是否存在神经性疼痛。从试验前基线和随访预约中提取疼痛（数字评定量表[NRS]）、功能（Oswestry功能障碍指数[ODI]）、生活质量（欧洲五维健康量表[EQ-5D]）的基线评估以及其他适用的关节调查结果。
确定并纳入了5例患者。患者诊断包括髋、膝或踝关节的顽固性关节疼痛。平均NRS疼痛评分从基线时的9.2改善了74%，至最后一次随访时为2.4（平均植入后28个月）。从基线到最后一次随访，平均ODI评分从66改善了65%，至23，EQ-5D评分从平均0.371增加了一倍多，至0.797。
本临床报告说明了DRG-S在治疗临床上主要表现为难治性机械性关节疼痛且无明显神经性成分的疼痛方面的潜在效用。我们观察结果的生理原因可能是DRG-S能够直接影响背根神经节和脊髓内伤害性信号的传导。有必要进行进一步研究以确定DRG-S是否是慢性机械性疼痛的一种潜在治疗选择。
