Asj.2017.11.4.642Asian Spine J 2017;11(4):642-652
Total Page:16
File Type:pdf, Size:1020Kb
Asian Spine Journal 642 Jae HwanReview Cho et Article al. Asian Spine J 2017;11(4):642-652 • https://doi.org/10.4184/asj.2017.11.4.642Asian Spine J 2017;11(4):642-652 Neuropathic Pain after Spinal Surgery Jae Hwan Cho1, Jae Hyup Lee2, Kwang-Sup Song3, Jae-Young Hong4 1Department of Orthopedic Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea 2Department of Orthopedic Surgery, SMG-SNU Boramae Medical Center, Seoul National University College of Medicine, Seoul, Korea 3Department of Orthopaedic Surgery, Chung-Ang University College of Medicine, Seoul, Korea 4Department of Orthopaedic Surgery, Korea University Ansan Hospital, Ansan, Korea Neuropathic pain after spinal surgery, the so-called failed back surgery syndrome (FBSS), is a frequently observed troublesome disease entity. Although medications may be effective to some degree, many patients continue experiencing intolerable pain and functional disability. Only gabapentin has been proven effective in patients with FBSS. No relevant studies regarding manipulation or physiotherapy for FBSS have been published. Spinal cord stimulation (SCS) has been widely investigated as a treatment option for chronic neuropathic pain, including FBSS. SCS was generally accepted to improve chronic back and leg pain, physical function, and sleep quality. Although the cost effectiveness of SCS has been proved in many studies, its routine application is limited considering that it is invasive and is associated with safety issues. Percutaneous epidural adhesiolysis has also shown good clinical outcomes; however, its effects persisted for only a short period. Because none of the current methods provide absolute superiority in terms of clinical outcomes, a multidisciplinary approach is required to manage this complex disease. Further studies concerning the etiology, diagnosis, treatment, and cost effectiveness of FBSS are warranted to deepen our understanding of this condition. Keywords: Neuralgia; Failed back surgery syndrome; Spinal cord stimulation; Percutaneous adhesiolysis Introduction spinal surgery have not been identified in many studies, this disease entity has been termed failed back surgery Neuropathic pain after spinal surgery is a frequently ob- syndrome (FBSS) or post-lumbar surgery syndrome. served troublesome disease entity for both patients and However, this is a misnomer because it gives an impres- surgeons [1-3]. Patients complain of persistent back or sion of wrong surgery, although no definite evidence is leg pain, regardless of the absence of neural compres- usually found to provoke the symptoms [7]. In addition, sion. Neuropathic pain is frequently not matched with many patients with neuropathic pain did not undergo the dermatome and is characterized by its severity and spinal surgery. Only minor traumas, such as a mild traffic continuity [4]. Although medications may be effective accident or falling down, can cause such severe and per- to some degree, many patients continue experiencing sistent neuropathic pain. In this respect, neuropathic pain intolerable pain and functional disability, leading to psy- after spinal surgery might be related to some changes in chological disturbances such as depression or insomnia the pain modulation process [8-10], which is supported [5,6]. Because the exact causes of neuropathic pain after by literature showing the effectiveness of spinal cord Received Nov 21, 2016; Revised Dec 20, 2016; Accepted Jan 3, 2017 Corresponding author: Jae Hwan Cho Department of Orthopedic Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, Korea Tel: +82-2-3010-3549, Fax: +82-2-3010-8555, E-mail: [email protected] Copyright Ⓒ 2017 by Korean Society of Spine Surgery This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. ASJ Asian Spine Journal • pISSN 1976-1902 eISSN 1976-7846 • www.asianspinejournal.org Asian Spine Journal Failed back surgery syndrome 643 stimulation (SCS). Many studies have attempted to reveal Clinical Outcomes of Each Treatment the etiology, epidemiology, treatment, and outcomes of FBSS. However, differing definitions and involvements of 1. Medication heterogeneous populations make it difficult to interpret the findings of such studies. With the recent dramatic Only gabapentin has been proven effective in patients increase in understanding neuropathic pain, outcomes with FBSS. In one randomized controlled trial, gabapen- of various treatments for FBSS have improved. However, tin, at a daily maximal dose of 1,800 mg, showed more none of the treatments completely resolved this complex clinical efficacy than naproxen [23]. Oral gabapentin with disease entity. Thus, this study aimed to review the clini- an epidural steroid injection showed better results than cal efficacy, adverse effects, and cost effectiveness of each the injection alone [24]. Pregabalin also has a preventive treatment modality for patients with chronic neuropathic analgesic effect on postoperative neuropathic pain [25]. pain after spinal surgery. Nonsteroidal antiinflammatory drugs have minimal ef- fects on FBSS [23]. The effect of antidepressants has not Etiology and Diagnosis of Neuropathic been reported. Although oral opioid is frequently used to Pain after Spinal Surgery relieve severe pain, its effectiveness in patients with FBSS is limited [26]. Various causes such as residual stenosis, instability, a synovial cyst, a pseudomeningocele, internal disk disrup- 2. Exercise, manipulation, and physiotherapy tion, epidural fibrosis, facet syndrome, sacroiliac joint syndrome, reflex sympathetic dystrophy, arachnoiditis, Only few studies have reported regarding the effect of ex- and psychological problems have been suggested as possi- ercise, manipulation, or physiotherapy on FBSS. A recent ble etiologies of neuropathic pain after spinal surgery [11- study evaluating different exercise programs reported 13]. Determining the exact causes are frequently difficult that isokinetic or dynamic lumbar stabilization exercises using magnetic resonance imaging or neurophysiological were more effective than home exercises [27]. No relevant studies. In addition, sagittal imbalance or back muscle articles have been found regarding the effect of manipula- problems can be potential causes of persistent pain [14- tion or physiotherapy on FBSS. Only one retrospective 16]. The difficulties in diagnosis lead to easy failure of any study showed the efficacy of chiropractic management of treatment. Revision surgical treatment reportedly showed lumbar spine pain after spinal surgery [28]. an inferior efficacy if the structural causes were not pre- operatively identified [17,18]. Thus, careful history taking, 3. Spinal cord stimulation physical examination, and reviews of pre- and postopera- tive status are considered basic and fundamental criteria SCS has been widely investigated as a treatment option for diagnosing FBSS. for chronic neuropathic pain, including FBSS. SCS was The diagnosis of FBSS is somewhat vague and not generally accepted to improve chronic back and leg pain, universal and is considered to include heterogeneous pa- physical function, and sleep quality [29,30]. The degree tients who exhibit residual symptoms after spinal surgery. of evidence was qualified in one systematic review, which The difficulty in defining this complex disease entity has showed level II-1 or II-2 by the U.S. Preventive Services been well described [19]. However, doctors recognize this Task Force for long-term relief [31]. Moreover, numerous characteristic disease, which is supported by one survey studies have shown SCS effectiveness (Table 1) [31-53]. study [20]. Although the Douleur Neuropathique en 4 Two randomized controlled trials compared SCS effec- and Leeds Assessment of Neuropathic Symptoms have tiveness with other treatments. A 2-year follow-up study been suggested as screening tools for neuropathic pain demonstrated the effectiveness of SCS and medication [21], they are less reliable for identifying the neuropathic in 48% and 9% of patients, respectively [54]. In the other component of FBSS [22]. This diagnostic ambiguity is study, SCS was more effective than repeated spinal surgery an obstacle in the clinical effectiveness of each treatment (47% vs. 12%, p<0.01) [55]. Regardless of its invasiveness modality. and several complications, SCS is considered to be a rela- tively safe technique [56]. 644 Jae Hwan Cho et al. Asian Spine J 2017;11(4):642-652 Table 1. Observational studies to reveal the effectiveness of spinal cord stimulation for FBSS No. of Follow-up Study Specific methods Conclusion patients (yr) De La Porte et al. [32] 78 SCS with unipolar 4 The 64 patients were successful during trial period. wire-type electrode Among them, the 35 patients continued to experience at least 50% pain relief at the latest follow-up. de Vos et al. [33] 45 SCS with hybrid lead 0.5 Of 42 patients, the VAS of LBP and leg pain decreased from 8.0 and 7.5 to 3.2 and 3.5, respectively (p<0.001). Devulder et al. [34] 69 SCS with a radiofrequen- 13 Forty-three patients continued with the therapy and cy-coupled or battery experienced good pain relief. system LeDoux et al. [35] 32 SCS 2 74% of the 19 patients with stimulators still present at 2 years were experiencing