Case Report

Journal of Advanced Spine Surgery

JASS

J. of Advanced Spine Surgery Volume 4, Number 2, pp 58~63

Tentative Spinal Stabilization Before Total en Bloc Spondylectomy Chi Heon Kim, M.D., Ph.D., Chun Kee Chung, M.D., Ph.D. 1)

Department of Neurosurgery, Seoul National University College of Medicine, Neuroscience Research Institute, Seoul National University Medical Research Center, Clinical Research Institute, Seoul National University Hospital, Seoul, Korea

Purpose: Total en bloc spondylectomy (TES) is one of curative surgical methods used for solitary spinal tumors, if indicated. However, TES is a complex technique and prudent preparation is mandatory. However, elective TES is not always possible for patients with neurological and mechanical spinal instability. In such situations, percutaneous pedicle screw fixation, with the purpose of stabilizing the spine and gaining time before TES, may be used. Methods: The first patient was a 29-year-old female who visited the emergency room (ER) due to progressive paraparesis (motor grade III/V) and back pain. Magnetic resonance imaging (MRI) showed compression of the spinal cord by a tumor and a collapsed L1 body. The second patient was a 23-year-old female who came to the ER with severe back pain. MRI revealed compression of the spinal cord by a collapsed T11 vertebral body and a tumor. In both cases, neurological and mechanical instabilities were caused by a primary vertebral tumor. For both patients, TES was an optimal surgical technique, but TES was not possible on an emergency basis. Results: In both patients, percutaneous pedicle screw fixation, distraction, and biopsy were performed on an emergency basis. Subsequently, weakness and/or pain improved in both patients. Elective TES operations were successfully performed 3 weeks or 1 month later. Conclusions: If TES is indicated, but preparation time is insufficient, tentative spinal stabilization with a percutaneous technique may be utilized before TES. However, considering the need for additional surgery, skin incision, and cost, this surgical strategy should be selectively applied. Key Words: Spinal tumors, Total en bloc spondylectomy, Stabilization, Spine, Tentative

Introduction For primary spinal tumors, the goal of surgery is a curative, wide or marginal resection of the tumor.1,2) Total en block spondylectomy (TES) was introduced in early 1990s and now is regarded as a curative surgical method for solitary spinal tumors, if indicated. 1) Indications of TES are usually the presence of solitary primary or secondary spinal tumors.2,1) Although TES is a useful surgical technique, it requires complex surgical procedures and prudent preparation. Moreover, TES has the potential to produce major complications due to the closeness of the surgical site to vital structures, such as the spinal cord and large vessels;

58

thus, surgeons should be prepared for emergent critical situations.2) Therefore, TES should not be performed on an emergency basis.1,2) However, performing TES as an elective surgery is not always possible when patients present with neurological and mechanical spinal instability. Corresponding author: Chun Kee Chung, M.D., Ph.D. Department of Neurosurgery Seoul National University College of Medicine 28 Yeongeon-dong, Jongno-gu Seoul, 110-744, South Korea TEL: 82-2-2072-2352, FAX: 82-2-744-8459 E-mail: [email protected]

*‌This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (2012-0000996). This study is approved by institutional review board of Seoul National University Hospital (H-1109-125-377)

© Copyright 2014 Korean Society for the Advancement of Spine Surgery

Journal of Advanced Spine Surgery

Recently, with the development of appropriate instruments, percutaneous pedicle screw fixation (PPSF) became possible, allowing the spine to be stabilized with a less invasive technique.3) We applied PPSF in two patients with primary spinal tumors who visited a hospital emergency room with paraparesis and/or severe back pain due to pathologic compression fracture of the spinal column. Through PPSF, we achieved tentative spine fixation and compression reduction with the purpose of stabilizing the spine and gaining time to prepare for TES.

Clinical Presentation Case 1. A 29-year-old female patient visited the emergency room (ER) in the evening and reported progressive weakness and severe back pain. The back pain started 10 months prior to the ER visit. After the initial occurrence of severe back pain, the subject underwent percutaneous spine biopsy and vertebroplasty at L1 in another hospital (Fig. 1A, B). A giant cell tumor was diagnosed and radiotherapy (3000 cGy/10 fractions) was given. Severe back pain redeveloped 1 month prior to the ER visit and progressive paraparesis started 10 days before the ER visit. At ER presentation, the patient could not walk due to paraparesis (motor grade III/V) and severe back pain. Magnetic resonance imaging (MRI) at the ER showed tumor progression. The spinal cord was compressed by a collapsed vertebral body and the tumor (Fig. 1C, D). The tumor was osteolytic and further collapse was expected (Fig. 1E). TES seemed to be an optimal surgical technique, but, without preparation, it was not possible to perform that evening. To gain time for TES preparation, we decided to stabilize the spine tentatively with percutaneous pedicle screws fixation. Eight pedicle screws were inserted through the eight stab skin incisions to the T11, T12, L2 and L3 bodies, and the L1 body was distracted with pedicle screws and a rod system (Fig. 1F) under general anesthesia. Percutaneous biopsy was performed for histological diagnosis. The operation took 1.5 h and blood loss was less than 100 ml. Three days later, the patient was discharged with a cane for support. One month later, TES was performed via a posterior approach. During the waiting period, the patient’s weakness

improved (to normal strength) and her pain was markedly reduced. Initially, during the TES operation, the previously installed screws and rod were removed. The surgical procedures that followed were similar to those previously reported.1,2) During the operation, the poly-axial screws, which were removed at the beginning of the operation, were not re-used and eight new mono-axial screws were inserted through the holes made at the first operation. TES of L1 was successfully performed without intraoperative complication (Fig. 1G, H). The spine was reconstructed by using a titanium mesh cage filled with autologous rib graft. Although transient chylothorax occurred, it disappeared without starving in one week and the patient was discharged on foot at postoperative day ten. Pathologic results after TES indicated chondroblastoma. A postoperative computed tomography (CT) scan taken 6 months after TES surgery showed solid bony fusion without evidence of tumor recurrence (Fig. 1I). Case 2. A 23-year-old female patient visited the SNUH ER for assessment of severe back pain. MRI revealed spinal cord compression due to a collapsed T11 vertebral body and a tumor (Fig. 2A, B, C). The spine was at the risk of further collapse and neurological deterioration due to the presence of an osteolytic tumor. For spine stabilization and histological conformation, tentative spine fixation with percutaneous pedicle screws, distraction, and percutaneous spine biopsy were performed on an emergency basis under general anesthesia (Fig. 2D). The operation took 1.5 h and blood loss was less than 100 ml. The patient was discharged 3 days later with improved pain. MRI performed 3 weeks after PPSF showed that spinal compression was relieved by ligamentotaxis (Figs. 2E, F). The histological diagnosis was a giant cell tumor. Three weeks after PPSF, elective TES was successfully performed (Fig. 2G, H). The surgical procedures were similar to those used in Case 1. The spine was reconstructed with a titanium mesh cage filled with autologous iliac bone graft and all PPSF screws were replaced with mono-axial ones. The patient was discharged at postoperative day seven without complication. She was followed-up for 6 months without recurrence of tumor. During follow-up, a CT scan revealed that solid bony fusion was achieved (Fig. 2I).

59

Journal of Advanced Spine Surgery

A

E

B

C

F

G

D

H

Fig. 1. T2-weighted sagittal (A) and T1-weighted gadolinium enhanced axial (B) magnetic resonance imaging (MRI) shows a solitary mass at L1 level. MRI taken 4 months later shows growth of tumor and increased spinal cord compression (C, D). Sagittally reconstructed computed tomography (CT) scan showing an osteolytic tumor (E). Plain X-ray after percutaneous pedicle screw fixation (F). Results of total en bloc spondylectomy performed 1 month later (G). The spine reconstructed by using a titanium mesh cage filled with autologous rib graft (H). CT scan obtained 6 months later shows solid bony fusion (I).

I

Discussion Through PPSF, we achieved tentative spine fixation and compression reduction with the purpose of stabilizing the spine and gaining time to prepare for TES in two patients. Wide resection of a primary bone tumor is a curative treat-

60

ment of choice according to the concepts of the Enneking classification.4) Although wide resection of a spinal tumor is not easy, due to the proximity of the spinal cord and large vessels, and associated biomechanical problems, marginal resection can be achieved by utilizing an anatomical barrier such as periosteum, cartilage, endplate, and (pseudo)capsule

Journal of Advanced Spine Surgery

A

E

B

C

F

D

G

Fig. 2. T2-weighted sagittal (A) and T1-weightend gadolinium enhanced axial (B) MRI shows the spinal cord compressed by a collapsed vertebral body and tumor at the T11 level. Plain X-ray showing collapsed T11 vertebral body by osteolytic tumor (C). Pain X-ray taken after percutaneous pedicle screw fixation shows that height of vertebral body is increased by distraction by using a rod and screw system (D). T2-weighted sagittal (E) and T1-weighted axial (F) MRI taken 3 weeks later demonstrates decompression of spinal cord by ligamentotaxis (compare with Figs. 2a and 2b). Results of TES performed 3 weeks later (G). The spine is reconstructed by using a titanium cage and pedicle screw and rod system (H). Sagittally reconstructed CT scan taken 6 months later shows solid bony fusion (I).

H

I

of the tumor, according to the classification of surgical strategies of the Global Spine Tumor Study Group (GSTSG).2,4,5)

Marginal resection showed a significantly lower chance of recurrence than intralesional resection in a multicenter

61

Journal of Advanced Spine Surgery

cohort study.4) Giant cell tumor and chondroblastoma are locally aggressive with a high rate of local recurrence; thus, wide excision of such tumors at first operation is deemed the best treatment of choice.6,7) However, marginal resection of a primary spinal tumor requires technically demanding procedures and imposes a higher risk to the patient, when compared to the less complex intralesional resection procedure.4) TES, which was developed by Tomita’s surgical group1) is a useful surgical technique for marginal resection of primary spinal tumors.1,5) The feasibility, background, and clinical outcomes of TES have been previously reported.1,2) The basic concept of the TES surgical technique is minimal exposure of tumor tissue by preservation of an anatomical barrier such as periosteum, cartilage, endplate, and (pseudo) capsule of the tumor.1,2) However, tumor cells are exposed through the pedicle opening, which is an inevitable part of the surgical procedure required to preserve the spinal cord.1,2) Laboratory research and clinical outcome study has shown that contamination of tumor cells through the pedicle opening results in a low chance of tumor recurrence.1,2) However, TES is a complex surgical technique and potentially may result in a major complication, such as massive bleeding and/or neurological injury.2) Preoperative embolization may be necessary.2) On those bases, TES may not be performed on an emergency basis. We were presented with two young female patients with progressive paraparesis and severe back pain. In both, MRI results showed primary spinal tumors with collapsed vertebral bodies. Moreover, their spinal cords were severely compressed by the collapsed vertebral body and tumor. Although the patients were me-

and dura of the spinal cord in TES might be reduced with indirect spinal cord decompression achieved with PPSF. However, this two-staged operation requires additional surgery, incision, resources, and cost. Moreover, surgeons need to obtain experience in long-level, PPSF and stabilization. Nonetheless, successful elective TES could be performed with the prior help of tentative spine stabilization.

chanically and neurologically unstable, TES was not possible on an emergency basis. With the development of appropriate surgical instruments, PPSF and stabilization of the spine is possible. Thus, we adopted the PPSF technique for tentative spine stabilization in order to gain time for preparation of TES and to obtain histological diagnosis confirmation. In addition to stabilization, indirect decompression was achieved by ligamentotaxis (Fig. 2). Mechanical failure did not occur during the waiting time prior to TES (Case 1, 1 month; Case 2, 3 weeks) and functional improvement was achieved in both cases. We suppose that the neurological injury risks during dissection between capsule of tumor

invasive techniques. Prog Neurol Surg. 19:135-151.

62

Conclusion If TES is indicated, but additional time is needed for surgical preparation, tentative spine fixation with a percutaneous technique may be considered. Through PPSF, neurological and biomechanical stabilization can be obtained, allowing for additional TES preparation time. However, considering the additional surgery, skin incision, and resource utilization, this strategy should be applied in selected cases.

REFERENCES 1. Tomita K, Toribatake Y, Kawahara N, Ohnari H, Kose H (1994). Total en bloc spondylectomy and circumspinal decompression for solitary spinal metastasis. Paraplegia. 32 (1):36-46. doi:10.1038/sc.1994.7. 2. Kawahara N, Tomita K, Murakami H, Demura S (2009). Total en bloc spondylectomy for spinal tumors: surgical techniques and related basic background. Orthop Clin North Am. 40 (1):47-63. doi:S0030-5898(08)00070-9 [pii] 10.1016/j.ocl.2008.09.004. 3. Gerszten PC, Welch WC (2006). Spine: minimally doi:95188 [pii] 10.1159/000095188. 4. Enneking WF (1986). A system of staging musculoskeletal neoplasms. Clin Orthop Relat Res. (204):9-24. 5. Choi D, Crockard A, Bunger C, Harms J, Kawahara N, Mazel C, Melcher R, Tomita K (2010). Review of metastatic spine tumour classification and indications for surgery: the consensus statement of the Global Spine Tumour Study Group. Eur Spine J. 19 (2):215-222. doi:10.1007/s00586-009-1252-x. 6. Kim SA, Cho KJ, Park YK, Lee JS, Kwon HJ, Chung H, Kim MJ (2011). Chondroblastoma of the Lumbar Spine

Journal of Advanced Spine Surgery

- A Case Report and Review of the Literature. Korean Journal of Pathology. 45 (5):532-536. doi:10.4132/KoreanJPathol.2011.45.5.532. 7. Junming M, Cheng Y, Dong C, Jianru X, Xinghai Y, Quan H, Wei Z, Mesong Y, Dapeng F, Wen Y, Bin N,

Lianshun J, Huimin L (2008).Giant cell tumor of the cervical spine: a series of 22 cases and outcomes. Spine (Phila Pa 1976). 33 (3):280-288. doi:10.1097/BRS.0b013 e318162454f00007632-200802010-00010 [pii].

척추체 적출술 이전에 임시 고정을 통해 척추의 안정화를 도모한 수술 - 증례 보고 김치헌, 정천기 서울대학교병원 신경외과

목적: 경피적 척추경 나사 삽입술 및 고정술을 이용하여 척추체 적출술 이전에 임시로 안정화를 도모하는 전략에 대해 소개한다. 선행 문헌 요약: 척추체 전출술은 척추체에 국한된 종양의 경우 치유를 위한 수술 방법 중 하나이다. 하지만 본 수술은 매우 복잡하 여 특히 술 전에 색전술, 수술부, 마취과등 준비하여야 할 부분이 많아서 응급으로 진행하기에 무리가 있다. 만약 환자의 신경학적 상태가 불안정 하거나 척추체가 불안정 하여 정규 수술 날자 또는 조직 검사를 기다리는 시간 동안 신경학적으로 악화가 우려되는 경우에는 경피적 척추경나사 고정술을 이용하면 임시로 척추체의 안정을 도모할 수 있다. 대상 및 방법: 응급실로 내원하여 신경학적인 장애가 있거나 척수 압박이 있으면서 단일 척추체에 국한된 종양 환자 2명에서 임시로 경피적 척추경 나사 고정술을 이용하여 환자의 상태를 안정화 하고 조직 검사 확인 그리고 수술 전 준비를 위한 충분한 시간 여유를 얻었다. 결과: 척추체 적출술 전에 위약 또는 통증은 호전이 되었고 정규 수술을 기다리는 동안 병동 보행에 지장이 없었다. 한 명의 환자는 경피적 척추경 나사 고정술 이후 자기공명영상에서 간접적 감압을 확인하였다. 척추체 적출술은 Tomita 방법으로 하였고 술 후 특 별한 합병증은 없었으며 술 전의 임시 고정으로 인한 수술 시 장애는 없었다. 결론: 척추체 적출술이 필요하지만 환자의 상태의 안정화 또는 조직 검사결과를 기다리는 동안 척추체의 안정화를 위하여 임시로 경 피적 척추체 고정을 하고 정규 수술을 준비하는 전략이 가능함을 보고 한다. 하지만 이는 두 번의 수술을 해야 하므로 꼭 필요한 경 우에만 적용하도록 한다. 색인단어: 척추 종양, 척추체 적출술, 안정화, 척추, 임시

63