Individualizing Radiofrequency Ablation Therapy in Two Patients with Bertolotti's Syndrome

Case Report

Individualizing Radiofrequency Ablation Therapy in Two Patients with Bertolotti's Syndrome

Philip A^* and Modzelewska M
Department of Anesthesiology and Physical Medicine and Rehabilitation, University of Rochester Medical Center, USA

^*Corresponding author: Annie Philip, Department of Anesthesiology and Physical Medicine and Rehabilitation, University of Rochester Medical Center, 601 Elmwood Avenue BOX 604 Rochester, NY-14642, USA

Published: 27 May, 2016
Cite this article as: Philip A, Modzelewska M. Individualizing Radiofrequency Ablation Therapy in Two Patients with Bertolotti's Syndrome. Ann Clin Case Rep. 2016; 1: 1004.

Abstract

Objective: Describe the clinical presentation, diagnostic evaluation, and successful treatment of two cases of Bertolotti's syndrome using radiofrequency ablation targeting levels based on the distribution of each individual patient's pain and radiological findings.
Case: We describe two cases of young patients with Bertolotti's syndrome resulting in axial low back pain. In case 1 the patient had Lumbarization of S1 vertebra hence the diagnostic block was performed with 0.5% bupivacaine along the pseudo-articulation and also we targeted the L5 medical branch and S1 lateral branch this resulted in complete pain relief. Radiofrequency ablation was performed of the same locations resulting in 100% pain relief for 10 months.
In case 2 the patient had partially sacralized L5 transitional vertebra hence the diagnostic block was performed with 0.5% bupivacaine along the pseudo-articulation and also we targeted the L4 and L5 medical branch this resulted in 80% pain relief. Radiofrequency ablation was performed of the same locations resulting in 80% pain relief which lasted for 7 months.
Conclusion: By describing these two cases of Bertolotti's syndrome we want to highlight how radiofrequency ablation therapy can be individualized depending on lumbarization or sacralization of the transitional vertebrae.

Keywords: Bertolotti's Syndrome; Pseudo articulation; Radiofrequency ablation

Background

Bertolotti's syndrome is defined as axial low back pain in the presence of lumbosacral transitional vertebrae, in which the enlarged transverse processes of the most caudal lumbar or the first sacral vertebrae either articulate or fuse with the sacrum or ilium to varying degrees. Bertolotti's syndrome is important to consider in the differential diagnosis of axial low back pain in young patients. This anatomical variant affects approximately 4-8% [1] of the population with a prevalence higher in males compared to females (28.1 vs 11.1%) [2]. Throughout literature the prevalence of individuals with lumbosacral transitional vertebrae seeking care for low back pain ranges from 4.6-35.6% [3-5]. The diagnosis of Bertolotti's syndrome is based on radiological findings and their clinical correlation [6].Plain X-rays of the lumbosacral spine in the anteroposterior view are usually sufficient. If patients present with radicular symptoms this may necessitate ordering of a lumbar spine MRI to rule out other etiologies.
As discussed previously, anatomic variations of lumbosacral transitional vertebrae have been described. The morphology can vary, from partial/complete L5 sacralization to partial/complete S1 lumbarization (Figure 1). Castellviet al. [7] classified LSTV into 4 types. Type I includes unilateral (Ia) or bilateral (Ib) dysplastic transverse processes, measuring at least 19 mm in width (craniocaudad dimension). Type II exhibits incomplete unilateral (IIa) or bilateral (IIb) lumbarization/ sacralizationwith an enlarged transverse process that has a diarthrodial joint between itself and the sacrum. Type III describes unilateral (IIIa) or bilateral (IIIb) lumbarization/sacralization with complete osseous fusion of the transverse process (es) to the sacrum. Type IV involves a unilateral type II transition with a type III on the contralateral side. Type I and Type II was the most common, accounting for 40% of the lumbosacral transitional vertebra. Type III accounted for 11.5% and Type IV for 5.25% [2].

Figure 1

Figure 1
Lumbarization of S1 vertebra.

Case 1

45 year old male with an eight year history of bilateral lumbar axial predominant low back pain. The patient described this as a burning pain, which was exacerbated with sitting or twisting while golfing. He rated his pain as 7-10/10. He denied any radiation of pain to his lower extremities and also denied any numbness or tingling in his lower extremities. The patient had participated in physical therapy and had been on antiinflammatory medication with minimal pain relief. Examination revealed reproduction of pain in the lower lumbar paravertebral region and in the upper sacral region. This pain was exacerbated by lateral rotation and extension. The patient's neurological exam did not reveal any deficits. Lumbar X-ray revealed lumbarization of the 1^st sacral vertebrae. Lumbar MRI did not reveal any significant pathology. Based on his physical exam and radiographic findings, the diagnosis of Berolottti's syndrome (Lumbosacraltransitional vertebra type IIb) was made. The decision was made to target the pseudoarticulation of the S1 transverse process and the sacral alae.
The first diagnostic block was performed under fluoroscopy using a 22 gauge 3.5 inch needle with 1cc each of 0.5% bupivacaine targeting the pseudo-articulation in the upper, middle and lower border of S1 transverse process and sacral alae bilaterally. Follow up phone call the next day revealed that patient had only 50% pain relief for 4 hours. A second diagnostic block was performed with 1cc of 0.5% bupivacaine at the L5 medical branch, 1cc of 0.5 % Bupivacaine at the S1 lateral branch and 1cc each of 0.5% bupivacaine along the pseudoarticulations in the upper, middle and lower border of S1 transverse process and sacral alae bilaterally. Follow up phone call after this procedure revealed that this provided him with 100% pain relief for 4 hours. Since he reported significant pain relief from the second diagnostic intervention, radiofrequency ablation was performed using a 20 gauge 10cm, 10mm RF needle at 80 degree centigrade for 80 seconds at the L5 medical branch, S1 lateral branch and three lesions along the upper, middle and lower border of the pseudo-articulations of the S1 transverse process and sacral alae bilaterally.
When the patient was seen for follow up 2 months after the procedure, he reported 100% pain relief lasting 10 months after the radiofrequency ablation, during which time patient was able to resume golfing.

Case 2

A 19 year old female presented to our clinic with axial predominant low back pain of three years duration. The patient described the pain as a burning, pressure like sensation in the lower lumbar region. She denied any radiation of pain down to her lower extremities. The pain was exacerbated by twisting, bending and sitting for prolonged period to time. She rated her pain 3-7/10. The patient had tried opioid medications, anti- inflammatory medications and physical therapy with minimal pain relief. On physical exam the pain was reproduced by palpation in the lumbar paravertebral region bilaterally. The pain was exacerbated by lumbar lateral rotation and extension bilaterally. Neurological exam did not reveal any deficits. Plain radiographs of her lumbar spine were obtained demonstrating a partially sacralized L5 transitional vertebra (Figure 2). Lumbar MRI showed minimal disc protrusion at L5-S1.
Her physical exam and review of the radiographic findings led to the diagnosis of Bertolotti's syndrome (lumbosacral transitional vertebrae type IIb). As the aforementioned case had provided positive results, the decision was made to target the pseudo-articulation of the L5 transverse process and the L4 and L5 medical branch.
The first diagnostic block was performed under fluoroscopy using a 22 gauge 3.5 inch needle with 1cc of 0.5% bupivacaine at L4 and L5 medial branches and also with 1cc each along the pseudo-articulation in the upper, middle and lower border bilaterally. Phone call after the procedure revealed that she had reported 80% pain relief after this intervention. Radiofrequency ablation was offered to provide sustained relief. Radiofrequency ablation was performed using 20 gauge 10cm, 10mm RF needle at 80 degrees centigrade for 80 seconds at the L4 and L5 medial branches and three lesions were performed along the upper, middle and lower border bilaterally at the pseudoarticulation.
When the patient was seen for her 2 month follow up, she continued to report 80% pain relief in the lower lumbar region which lasted for 7 months after the radiofrequency ablation. Medication usewas no longer necessary and the patient were able to return to full functionin school.

Figure 2

Figure 2
Partially sacralized L5 transitional vertebra.

Discussion

Lumbosacral transitional vertebrae are increasingly recognized as common anatomical variants associated with altered patterns of degenerative spine changes. The causes of back pain in Bertolotti's syndrome are multifactorial. Pseudo articulations between the transverse process and the sacrum create a "false joint" susceptible to arthritic changes and osteophyte formation potentially leading to nerve root entrapment. Abnormal mechanical stress can lead to facet arthropathy as a contributing factor [8]. Other causes include iliopsoas and quadratus lumborum strain, nerve root compression due to the narrowing of the intervertebral foramen,and disc protrusion or extrusion in the disc above the transitional L5 vertebra.
The other common differential diagnosis to be considered for axial predominant low back pain are muscle strain or ligamentous injury, degenerative disc disease, spondylolysis, facet mediated pain, primary or secondary neoplastic disease, infection and Baastrup's disease.
As the study by Bogduk and Long [9] indicated that medial branches transmit pain sensation from the capsule of the facet joints from the level above and same level, there has been numerous studies published about the efficacy of radiofrequency ablation for treatment of facet mediated low back pain. A systematic review of randomized controlled trials of radiofrequency ablation for lumbar facet joint pain [10] revealed 6studies. All six studies assessed pain reduction using a visual analogue scale. Five of the studies found evidence of statistically significant pain relief when compared to sham RFA. One of studies did not show any evidence of statistically significant benefit.
Although there have been multiple studies in the literature about radiofrequency ablation for lumbar facet pain, there has been only one case report by Burnham [11]in the literature describing the benefit of radiofrequency ablation for Berolotti's syndrome.

Conclusion

Bertolotti's syndrome should be considered in the differential diagnosis of young patients presenting with axial predominant low back pain. To date, there has been no consensus about the best method for the treatment of Bertolotti's syndrome. Radiofrequency ablation can be a successful option for management of pain in patients with Bertolotti's syndrome. The above mentioned cases demonstrate how this therapy can be individualized depending on lumbarization or sacralization of the transitional vertebrae.

Case Report