Endoscopic Approaches To The Spine DEMO

Endoscopic Approaches To The Spine Editor: Dr. Salim Şentürk Associate Editors: Dr. İdris Avcı, Prof. Dr. Ali Fahir Özer US Akademi

Endoscopic Approaches To The Spine Editor: Dr. Salim Şentürk, Associate Editors: Dr. İdris Avcı, Prof. Dr. Ali Fahir Özer ©E-Book 2023 ©Print Book 2019 The contents and rights and responsibilities of this book are owned by the editor. Print, publication, distribution and sales rights belong to US Akademi. Mechanic, electronic, photocopy, magnetic prints or multiplication of this medium of any kind is restricted without the consent of the authors. Publication editor: Dr. Hüseyin Özkan Project coordinator: E. Armağan Karaağaçlıoğlu Design: US Akademi Graphics Department - Izmir/Turkey Print and publication: US Akademi Publication certificate number: 33511 Webpage: www.intertipyayinevi.com e-mail: [email protected], [email protected] Customer Service: [email protected] www.intertipyayinevi.com - www.usakademi.com ISBN: 978-605-9358-75-0 The contents of this medium are based on current knowledge in a medical field which is constantly variable and updating itself. But as the editors and publishers of this book, we cannot guarantee that all the information mentioned in it will be permanent and might contain human errors. The chapters in this book are based on the authors’ daily routine and experience. We want to emphasize that the medical diagnosis and treatment options of a pathology mentioned in this medium are responsibilities of the patient’s physicians in charge.

This book is dedicated to my beloved friend Op. Dr. Ersin Arslan who was killed on duty and to all other murdered physicians and their families. Dr. Salim Şentürk 20.03.2019

v Editor Salim Şentürk Associate Editors İdris Avcı, Ali Fahir Özer Authors Ahmet Gürhan Gürçay Kemal Paksoy Ali Dalgıç Koray Ur Ali Fahir Özer Mehdi Sasani Ali Güven Yörükoğlu Mesut Emre Yaman Ali Haluk Düzkalır Nitin Adsul Altay Sencer Onur Erdoğan Barış Arslan Onur Yaman Emrah Egemen Salim Şentürk Erkan Kaptanoğlu Seong-Hoon Oh Fatih Yakar Serdar Çevik Göktuğ Akyoldaş Timur Yıldırım Gülşah Öztürk Toğrul Cavadov Hikmet Uluğ Tolga Tolunay Hyen Sung Kim Tuncer Süzer Il-Tae Jang Tunç Laçin İdris Avcı Tunç Öktenoğlu İsmail Bozkurt Ülkün Ünlü Ünsal İsmail İştemen Yahya Güvenç Zeynep Turan

vii Authors Assoc. Prof. Dr. Ahmet Gürhan Gürçay Prof. Dr. Hikmet Uluğ Ankara Yıldırım Beyazıt University, Medical Neurology Center Merkezi, Istanbul – Turkey Faculty, Department of Neurosurgery, Ankara – Turkey Hyeun Sung Kim, MD, PhD Nanoori Hospital, Department of Neurosurgery, Assoc. Prof. Dr. Dr. Ali Dalgıç Seoul – South Korea Ankara Numune Training and Research Hospital, Department of Neurosurgery, Ankara – Turkey Il-Tae Jang MD, PhD Nanoori Hospital, Department of Neurosurgery, Prof. Dr. Ali Fahir Özer Seoul – South Korea Koç University Hospital, Spine Center, Istanbul – Turkey Dr. İdris Avcı Okmeydanı Training and Research Hospital, Dr. Ali Güven Yörükoğlu Department of Neurosurgery, Istanbul - Turkey RiwoSpine GmbH Clinical Manager Consultant and Neurosurgeon, Knittlingen - Germany Dr. İsmail Bozkurt Çankırı State Hospital, Department of Dr. Ali Haluk Düzkalır Neurosurgery, Çankırı - Turkey Lütfi Kırdar Kartal Training And Research Hospital, Department of Neurosurgery, Dr. İsmail İştemen Istanbul – Turkey Adana City Training And Research Hospital, Department of Neurosurgery, Adana – Turkey Prof. Dr. Altay Sencer Istanbul University Çapa Medical Faculty, Dr. Kemal Paksoy Department of Neurosurgery, Kaçkar State Hospital, Department of Istanbul – Turkey Neurosurgery, Rize – Turkey Dr. Barış Arslan Dr. Koray Ur Pamukkale University, Department of Çiğli District Training Hospital, Department of Neurosurgery, Denizli – Turkey Neurosurgery, Izmir – Turkey Dr. Emrah Egemen Prof. Dr. Mehdi Sasani Pamukkale University, Department of Koç University Hospital, Spine Center, Neurosurgery, Denizli – Turkey Istanbul – Turkey Prof. Dr. Erkan Kaptanoğlu Assoc. Prof. Dr. Mesut Emre Yaman Marmara University Medical Faculty, Department Gazi University Medical Faculty, Department of of Neurosurgery, Istanbul – Turkey Neurosurgery, Ankara – Turkey Dr. Fatih Yakar Nitin Adsul, MD Pamukkale University, Department of Nanoori Hospital, Department of Neurosurgery, Neurosurgery, Denizli – Turkey Seoul – South Korea Dr. Göktuğ Akyoldaş Dr. Onur Erdoğan Koç University Hospital, Spine Center, Marmara University Medical Faculty, Department Istanbul – Turkey of Neurosurgery, Istanbul – Turkey Dr. Gülşah Öztürk Assoc. Prof. Dr. Onur Yaman Acıbadem Halkalı Hospital, Department of Koç University Hospital, Spine Center, Neurosurgery, Istanbul – Turkey Istanbul – Turkey

viii Dr. Salim Şentürk Prof. Dr. Tuncer Süzer Koç University Hospital, Spine Center, Koç University Hospital, Spine Center, Istanbul – Turkey Istanbul – Turkey Seong-Hoon Oh, MD, PhD Assoc. Prof. Dr. Tunç Laçin Nanoori Hospital, Department of Neurosurgery, Marmara University Medical Faculty, Department Seoul – South Korea of Thoracic Surgery, Istanbul – Turkey Dr. Serdar Çevik Prof. Dr. Tunç Öktenoğlu Memorial Hospital, Department of Neurosurgery, Koç University Hospital, Spine Center, Istanbul – Turkey Istanbul – Turkey Assist. Prof. Dr. Timur Yıldırım Dr. Ülkün Ünlü Ünsal Ordu University Medical Faculty, Department of Manisa State Hospital, Department of Neurosurgery, Ordu – Turkey Neurosurgery, Manisa - Turkey Dr. Toğrul Cavadov Dr. Yahya Güvenç Marmara University Medical Faculty, Department Marmara University Medical Faculty, Department of Neurosurgery, Istanbul – Turkey of Neurosurgery, Istanbul – Turkey Dr. Tolga Tolunay Dr. Zeynep Turan Gazi University Medical Faculty, Department of Koç University Hospital, Department of Physical Orthopedics and Traumatology, Ankara – Turkey Therapy and Rehabilitation, Istanbul – Turkey

ix Contents 1. History of Endoscopic Spine Surgery 1 İsmail İştemen 5 2. Advantages and Disadvantages of Endoscopic Spine Surgery 11 Serdar Çevik 17 23 3. Set-up of the Operating Theater in Endoscopic Spine Surgery and 45 Surgical Instruments 51 Timur Yıldırım 61 69 4. Anesthesia in Endoscopic Spine Surgery 73 İsmail İştemen, Barış Arslan 81 5. Rehabilitation After Endoscopic Spine Surgery 93 Zeynep Turan 99 103 6. Endoscopic Anatomy of The Cervical Spine 107 Emrah Egemen, Fatih Yakar, Tuncer Süzer 111 7. Endoscopic Cervical Posterior Foraminotomy and Discectomy Hyen Sung Kim, Nitin Adsul, Il-Tae Jang, Seong-Hoon Oh, İdris Avcı 8. Percutaneous Endoscopic Cervical Laminoforaminotomy Ali Dalgıç 9. Complications of Endoscopic Cervical Surgery Tunç Öktenoğlu, Koray Ur 10. Endoscopic Anatomy of The Thoracic Spine Erkan Kaptanoğlu, Yahya Güvenç, Tunç Laçin, Toğrul Cavadov, Onur Erdoğan 11. Thoracoscopic Discectomy Ülkün Ünlü Ünsal, Ali Fahir Özer 12. Endoscopic Approaches to The Thoracic Spine Percutaneous Endoscopic Thoracic Discectomy (PETD) İsmail Bozkurt, Onur Yaman 13. Endoscopic Transpedicular Thoracic Discectomy Mesut Emre Yaman, Tolga Tolunay 14. Complications Associated with Endoscopic Thoracic Spinal Surgery Mehdi Sasani, Gülşah Öztürk 15. Endoscopic Anatomy of The Lumbar Spine Göktuğ Akyoldaş 16. Transforaminal Endoscopic Discectomy Hikmet Uluğ

x 129 135 17. Posterolateral Endoscopic Lumbar Discectomy 143 Ali Haluk Düzkalır, Salim Şentürk 151 167 18. Interlaminar Endoscopic Discectomy 171 Altay Sencer, Ali Güven Yörükoğlu 19. Endoscopic Approaches to Lumbar Spinal Stenosis Ülkün Ünlü Ünsal 20. Endoscopic Approaches to Various Spinal Pathologies Salim Şentürk 21. Complications of Endoscopic Lumbar Discectomy Kemal Paksoy, Ahmet Gürhan Gürçay Index

xi Preface Technical innovations are supposed to make a person’s life more comfortable. It is a continuous process. There are special factors a surgeon has to take notice of when a patient is confronted with a surgical treatment. Firstly, standardization of the treatment. Then avoidance of unnecessary anatomical damage. With special tools this avoidance of unnecessary damage is possible. A fasci- nating experience for me as a child was when I took my wrist watch for repair and the watchmaker examined my watch with a loupe for its possible error like diagnosing a patient. A watch containing hundreds of millimetric pieces which had to be magnified with a special tool to fix it, like a surgeon uses special surgical tools for treating a patient. Endoscopic approaches have been used for a century now, but in neurosurgery it became popu- lar after Yaşargil introduced the surgical microscope. Today’s microendoscopic procedures rely on Yaşargil’s nuances. All in all, the aim of endoscopic spine surgery is based on seeing a magnifica- tion of the surgical field with the endoscope, and treating the patient. Tissue damage is minimal compared to classic microsurgery and it is certain that in the future newer surgical tools will be developed to provide much better outcomes. In my faculty years, gastroenterologists could only observe the pathology, take images and biop- sies with endoscopic tools. Today, the editor of this book was able to remove a patient’s intradural tumor with the endoscope which is a quite challenging procedure. The authors of this book and the ones who contributed to it are those who practiced their art with love and provided an excellent end product with their work. I hereby congratulate Dr. Salim Şentürk for his contribution to Turkish medicine and wish him all the best for his bright future. Ali Fahir Özer

The History of Endoscopic Spinal Surgery 1 1 The History of Endoscopic Spinal Surgery •İsmail İştemen German physicist Philip Bozzini invented Minimal invasive approaches first started the conventional endoscopy in 1806.(1) Bozzi- with the chymopapain injection into the disc ni’s idea of Bozzini formed the fundamentals space by Lyment Smith in 1963 which was na- the fundamental for the classic open and en- med chemonucleolysis.(4) Kambin performed doscopic approaches of today. It revealed the a percutaneous discectomy by using a Craig’s idea of obtaining a clearer and wider surgical cannula to empty the disc with a posterolate- field of view by using a light source to penet- ral approach in 1970. Again, in that period, he rate into the natural openings of the body. In described the most important entrance area - 1853, Desmormoeaux, succeeded in reflecting Kambin’s triangle - for percutaneous minimal light directly by designing a lens with an al- invasive posterolateral approaches.(5,6) The- cohol-based liquid and increased the display reafter, Kambin described endoscopic laser quality.(2,3) In spite of those improvements at discectomy and arthroscopic microdiscectomy. the beginning of the 20th century, endoscopic (7,8) In 1975, Hijikata et al. stated the results approaches were not commonly used until the of posterolateral percutaneous central discec- 1990’s because of technological shortcomings tomy under local anesthesia. They published and growing complications. With the rapid de- a success rate of 64% and named the method velopment of the technology in 90’s, endosco- mechanic nucleotomy.(9) In 1983, Friedman pic surgery became popular again. described percutaneous discectomy in which he used a 40 Fr. thorax tube as a cannula for Surgical therapy for spinal diseases has evol- an alternative to chemonucleolysis which was ved to more minimal invasive techniques over frequently used in those years.(10) In 1985, Onik time with the improvements in displaying et al. described a percutaneous discectomy techniques and technological developments. performed with an automatic aspirator called Before mentioning endoscopic surgery in spi- nucleotomy probe. This probe had a length of nal surgery, one should consider the develop- 20.3 cm and a diameter of 2 mm and worked ments in minimal invasive approaches. as a system to cut the disc and aspirate it with water.(11)

Advantages and Disadvantages of Endoscopic Spinal Surgery 5 2 Advantages and Disadvantages of Endoscopic Spinal Surgery •Serdar Çevik Surgical treatment of spinal disc diseases has Endoscopic Cervical Spine Surgery rapidly evolved from conventional open spi- nal surgery to minimally invasive procedures. Symptoms of degenerative diseases of the Advances in high-resolution cameras, light cervical spine may present with disc hernia- sources, endoscopic optics, high-speed drills, tions, osteophytes, hypertrophied facet joints and irrigation systems have allowed lumbar, and thickened ligamentum flavum, and en- cervical, and thoracic endoscopic spine sur- trapment of the spinal cord within the inter- gery techniques to be performed through vertebral canal or of the spinal roots in the minimally invasive methods.(1-3) While endo- foramina. If conservative treatment is insuf- scopic lumbar, cervical, and thoracic surgical ficient or progressive neurological deficits techniques were at first used for disc herni- develop, surgical treatment is required. Since ations, improved techniques and technologies the middle of the twentieth century, conven- facilitated their use in surgical procedures for tional posterior or anterior approaches have spinal stenosis and fusion.(4-7) been described as safe and adequate surgical procedures for the treatment of symptomatic The high demand for maintaining daily liv- cytological degenerative diseases.(8,9) Howev- ing standards requires early postoperative er, the fact that endoscopic procedures such as healing and early resumption of every-day arthroscopy and laparoscopy have become the life duties. Therefore, the need for minimal- gold standard in a variety of therapeutic areas ly invasive methods increases day by day. and that improved clinical outcomes were ob- These techniques have important benefits tained from lumbar spinal endoscopic surgery such as less soft tissue damage, shorter sur- provided acceleration of the development of gery time, minimal blood loss, and shortened endoscopic techniques in cervical spine sur- hospital stay, all without compromising clini- gery.(10-17) In 1999 Fontenella described the cal outcomes. In addition, unlike epidural and anterior and posterior endoscopic technique nerve root injections, minimally invasive sur- to treat herniated cervical discs and achieved gical methods do not only target symptomatic good clinical outcomes.(18) Endoscopic anteri- treatment, but target effective treatment and or cervical interventions may be considered the same outcomes via nerve root decompres- as an appropriate alternative to conventional sion as from traditional surgical methods. anterior cervical discectomy and interbody fu-

Set-up of the Operating Theater in Endoscopic Spinal Surgery and Surgical Instruments 11 3 Set-up of the Operating Theater in Endoscopic Spinal Surgery and Surgical Instruments •Timur Yıldırım Introduction The Set Up of the Operating Room Low back pain ranks among the top health It is important that the endoscope and fluo- problems for which people seek medical help. roscopy monitors in the operating room are (1) Lumbar disc herniation is one of the reasons positioned and arranged in a way that is com- for low back pain ranking among the most fre- fortably and easily visible to the surgeon. The quent causes for visiting neurosurgery outpa- patient is put in prone position on a radiolu- tient clinics. It comprises 2-5% of all low back cent table with a pelvic and a thoracic roll to pain cases, but it actually is the majority in en- avoid compression of neurologic and vascular doscopic spinal surgery practice.(2) structures. The position of the surgeon and the operating table should be set according to Nowadays, in the field of spinal surgery, min- the side of the spinal pathology enabling the imally invasive surgical techniques are pre- surgeon to see both the C-arm and endoscope ferred, as they cause less postoperative pain, monitor at the same time (Figure 1). Prefera- have early recovery, less adhesion and scar bly, the endoscope monitor should stand right tissue, and better cosmetic outlook.(2,3,4) The in front of the surgeon and the C-arm monitor transition to minimally invasive approach in should be positioned just next to it. The C-arm spinal surgery became routine practice with should be set according to the position of the the definition of microdiscectomy by Yaşargil operating table to obtain both lateral and an- and Caspar, which is still the gold standard. terior-posterior images by allowing rotation In 1983 Kambin and Gellman defined the under the table. It is important that both sides posterolateral percutaneous endoscopic ap- of the C-arm are covered with sterile drapes, proach.(5,6,7) Many techniques have been devel- all the light sources for the camera are con- oped in time, particularly the full-endoscopic nected, and the imaging stand and scope interlaminar approach defined by Ruetten and monitor are positioned correctly. In many Choi in 2006 which has become a routine treat- centers, nowadays, imaging monitors hanging ment method.(4,7) down from the ceiling of the operating room are used instead of imaging stands occupying quite a large space next to the operating table.

Anesthesia in Endoscopic Spinal Surgery 17 4 Anesthesia in Endoscopic Spinal Surgery •İsmail İştemen •Barış Arslan General Review satisfaction. It does not need airway manip- ulation and multiple drug usage so that the The main goal in preoperative assessment is effect on the patient’s hemodynamics is min- the early diagnosis of risk factors which might imal and it provides quicker recovery in com- adversely affect the surgical therapy, decreas- parison with general anesthesia. If a deeper ing the preoperative care costs and recovering sedation occurs more than desired, it should the patient to the desired functions as soon as be foreseen that serious respiratory distress possible. All patients are subjected to an as- or cardiac depression might be caused. Rapid sessment system, which preoperatively clas- and proper actions should be taken to prevent sifies the patient, developed by the American hypoxic brain damage, cardiac arrest or even Society of Anesthesiologists (ASA) accepted death. While insufficient sedation/analgesia as the gold standard.(1,3) The main aims of the decreases the chances of success, it may lead preoperative assessment are consideration of to discomfort of the patient and even physio- the medical history of the patient, understand- logical and psychological damage. ing systemic findings thereof, detailed neuro- logical assessment, providing all comorbidity Monitored anesthesia care is a preferred optimizations and creating a proper and safe method with local anesthesia in transforam- anesthesia schedule.(2) inal minimal endoscopic surgery. The standard monitorization in form of anesthetic agent Basic Anesthesia Techniques monitorization, ECG, blood pressure, pulse oximetry, capnography, and body temperature As the sedation anesthesia, regional anesthe- should be done.(4) The capnograph allows the sia or general anesthesia can be used in mon- anesthetist to follow the respiration of the pa- itored anesthesia care, combined techniques tient during sedation.(5) might be used as well. Bispectral index monitorization derived from 1. Monitored Anesthesia Care electroencephalography can be of great bene- fit in determining the depth of intraoperative For monitored anesthesia care, we mean the anesthesia.(6) usage of intravenous sedative and analgesic drugs with local anesthesia. Its basic target is ensuring the patient’s safety, comfort and

Rehabilitation After Endoscopic Spinal Surgery 23 5 Rehabilitation After Endoscopic Spinal Surgery •Zeynep Turan The aim of percutaneous endoscopic spine The main objective of rehabilitation in the surgery is the decompression of neural struc- recovery period is to decrease pain, improve tures with minimal anatomic and physiologic stability, decrease potential mechanical stress- damage. The technique can be performed via es on the spinal structures, establish straight transforaminal, interlaminar or translaminar posture, and strengthen weak muscles. approach according to the case. Avoiding ex- tensive dissection preserves anatomical integ- Stabilization of the Spine and the rity of muscles, ligaments and bones, the load Structure of the Disc bearing system is not compromised; there- fore, the risk of instability is minimalized. Stabilization of the spine is provided by three The area of interest can be exposed through systems. The passive system is formed by ver- a 7 mm incision, decreasing traumatization of tebrae, discs and ligaments; the active system the surrounding tissue. As a result, shorter is formed by muscles and tendons, and the hospitalization time, early rehabilitation and neural control system is formed by the cen- earlier return to work can be ensured.(1) This tral nervous system.(4) The main objective is to approach which is less traumatic than other improve the active system following surgery. methods provides faster and more painless re- The most important muscle group in the active covery period and also better short- and long- system is the core muscles. The core center term outcomes.(2) comprises the abdominal muscles at the front, paraspinal and gluteal muscles at the back, Aim of Rehabilitation pelvic muscles at the bottom and diaphragm at the top. Co-contraction of the muscles in this Early return to normal activities (before 2 region acts as a corset, thereby supporting the weeks after surgery) and sitting for a long spine’s stability. According to the kinetic chain time may cause relapse during the first post- rehabilitation approach by simultaneously operative year.(3) Therefore, the aim of reha- exercising numerous parts of the body, these bilitation following endoscopic spine surgery three systems work together and rehabilita- is to improve the function of the patient and tion of the whole neuromuscular system can provide for a return to normal daily activities be provided.(5) as soon as possible without taking any risks.

Endoscopic Anatomy Of Cervical Spine 45 6 Endoscopic Anatomy of Cervical Spine •Emrah Egemen •Fatih Yakar •Tuncer Süzer Introduction specific anatomic structures can be utilized for determining the precise surgical level. Hyoid Comprehensive understanding of surgical bone, trachea, and the clavicular head (ster- anatomy for any procedure provides better noclavicular joint) are some of these critical surgical outcomes and avoids complications. anatomical structures other than the SCM. Of Consideration of three-dimensional topo- course, identification of the precise disk level graphic anatomy is essential, especially for utilizing C-arm fluoroscopy at the beginning minimally invasive procedures such as endo- of surgery just after positioning overcomes scopic approaches to the spine. Endoscopic any individual variations which may affect de- approaches to the cervical spine are evaluated cisions about the skin incision.(1) under four groups; anterior and posterior ap- proaches to the craniocervical junction, anteri- - The hyoid bone, is located 1.5 cm above the or and posterior approaches to the lower cer- thyroid cartilage and is at the level of the vical spine. Important anatomical structures body of the C3 vertebra. Therefore, the in- for the endoscopic approach to distinct areas ferior edge of the hyoid bone is targeted to of the lower cervical region are presented in approach the C3-4 intervertebral disc level. this chapter. The superior thyroid artery is located at that trace. Superficial Anatomy for Anterior Cervical Approach - The thyroid cartilage, is the most prom- inent midline structure that can be easily Comprehension of external anatomy is crucial distinguished especially in males after ado- for indicating the correct disc level and ap- lescence. The C4-5 intervertebral disc and propriate tracking of the needle to the inter- the carotid bifurcation are placed at same vertebral disc space. The sternocleidomastoid projection. The pharynx is located more me- (SCM) muscle is the most prominent anatomi- dially to the lateral edge of the thyroid car- cal structure which can be distinguished from tilage. Thus, the risk of pharyngeal injury is the outside and divides neck into the anterior less common at this level. and posterior triangle. However, neck length, body weight and con- struction of the chin can vary individually;

Endoscopic Cervical Posterior Foraminotomy and Discectomy 51 7 Endoscopic Cervical Posterior Foraminotomy and Discectomy •Hyen Sung Kim•Nitin Adsul•Il-Tae Jang•Seong-Hoon Oh•İdris Avcı Introduction Characteristics of nerve root: Cervical radiculopathy occurs when a nerve The rootlets (6-8 per level) run oblique lat- root is compressed or irritated where it erally and distally within the foramen where branches away from the thecal sac. The clini- they join to form ventral (motor) and dorsal cal presentations of this neurological condition (sensory) roots. The dorsal and ventral roots are vast and may include pain, sensory loss, are separated by the interradicular septum; motor deficits, diminished or absent reflexes, in addition, they are surrounded by a lateral or any combination of the above.(1) Compres- extension of the dura mater. Every dorsal root sion of the cervical nerve root may occur due has an oval enlargement, the spinal gangli- to disc prolapse or bony osteophytes that im- on, just distal to the foramen. Lateral to this pinge on the cervical nerve root. In most cas- ganglion, the dorsal and ventral roots unite to es, cervical radiculopathy responds well to form a spinal nerve. The cervical nerve root conservative treatment and few may require usually occupies the lower one-third of the surgery.(2) This chapter focuses on endoscopic neural foramina; the upper part is filled with cervical posterior foraminotomy and discecto- fat and related veins. Due to peculiar anato- my for patients with cervical radiculopathy. my, prolapsed disc usually causes ventral root compression, osteophytes from the facet joint Anatomy cause dorsal root compression and severe ca- nal compromised by either pathology can com- - Anterior: Uncinate process, the posterolat- press both roots. The cervical nerve roots en- eral portion of the intervertebral disc and ter the neuroforamina at the level of the disc the inferior portion of the vertebral body, and exit on top of the pedicle of the respective level, except for C8, which exits on top of the - Posterior: Facet joint and the superior artic- T1 pedicle. ular process of the inferior vertebral body, The usual site of compression of the radicular - Superior and inferior: Pedicles above and nerve is at the entry into the intervertebral fo- below ramen because: - Dimensions: 9-12 mm in height, 4-6 mm in width and 4-6 mm in length - Content: Nerve roots, fat and small veins.(3,4)

Percutaneous Endoscopic Cervical Lamino-Foraminotomy 61 8 Percutaneous Endoscopic Cervical Lamino-Foraminotomy •Ali Dalgıç The cervical region is the most mobile part In this section we will discuss the use of percu- of the spine. It is responsible for rotating the taneous endoscopic lamino-foraminotomy, one head like an antenna for aiming the organs re- of the posterior techniques, for surgical man- sponsible for sight, olfaction, and hearing to a agement of cases diagnosed with CDH. target for vital functions. In addition to bear- ing the head, it provides rotative movement History in three basic axes and their composite axes. Hence, developing cervical disc hernia (CDH) Surgical treatment methods targeting the as a result of the aging process and the result- cervical spine and CDH are older than the an- ing degeneration must be considered a natural terior approaches. In 1895 Sir Victor Horsley part of our lives. CDH affects the quality of became the pioneer of surgical treatment for life and usually requires treatment. cervical spine diseases after performing C6 laminectomy with favorable results. In 1928 Posterior lamino-foraminotomy is defined as Stookey published a clinical syndrome origi- the procedure of removing soft disc sequestra- nating from CDH; however, he reported that tions extending into the foramina and neural case as a chondroma or a tumor of notochord decompression via foraminotomy. It is usually origin. Subsequently, in 1929, Dandy revealed performed with an open technique, and hence that that chondroid material was actually nor- with wide muscle dissection, its effectiveness mal disc tissue.(4,5) during and after the operation was controver- sial. Therefore, it has lost its importance after The first anterior approach to the cervical the widespread use of anterior cervical discec- spine to perform discectomy was performed tomy. However, it re-gained its popularity after in 1954 by Smith and Robinson using a graft the invention of the surgical microscope and named after themselves. With the advent of tubular retractor systems have reduced the instrumentation systems, Caspar and col- use of muscle dissection. After the introduc- leagues started using stabilization in anteri- tion of the endoscopic discectomy technique, or cervical interventions. On the other hand, very favorable results have been achieved in Fager et al. and Scoville and Kahn started us- well-selected patients. ing the posterior approach again after it fell out of favor in the 1970s. With the introduction

Complications of Endoscopic Cervical Surgery 69 9 Complications of Endoscopic Cervical Surgery •Tunç Öktenoğlu •Koray Ur The aim of a surgical intervention is to treat a including the meticulous identification of eligi- particular pathologic lesion effectively, ensur- ble cases, the performance of interventions by ing that a minimal level of disruption occurs spinal surgeons who are experienced partic- to the normal anatomic structures.(1) Although ularly in endoscopic interventions, surgeons’ spinal surgeries have long been practiced, avoiding publication of any complications en- treatment with minimally invasive surgical countered, or lower frequency of complica- techniques has received attention in the most tions. recent 20 years.(2) The minimally invasive sur- gical interventions are increasingly preferred Jeffrey et al., compared the minimally-inva- since they carry a limited risk of adverse con- sive spinal surgeries with open surgery and sequences compared to conventional open reported decreased blood loss, shorter hospi- surgery. Minimal-invasive procedures lead to tal stay and lower use of postoperative anal- a shorter hospital stay and decreased used of gesics.(8) postoperative analgesics.(3) The introduction of cervical endoscopic surgery has led to it be- However, Epstein proposed that a negative coming the most commonly used minimally in- risk-to-benefit ratio is present in cervical vasive spinal surgery method in recent years, foraminotomies performed with minimally after advances due to newer technologies.(4) invasive surgery, supporting the use of open techniques. Epstein emphasized that the ac- Endoscopic cervical surgery was first de- tual complication rates are unknown and the scribed for cadavers in 2000. In the year 2001, morbidity and even mortality rates may be the first use in a clinical setting was report- high during relatively long periods of training ed.(5,6) Each individual surgical technique has for the minimally invasive surgical methods.(9) unique complications or limitations despite the recent advances in cervical disc surgery.(7) Potential Complications In the current literature, there are no detailed Vascular Injuries publications about the complications of cervi- cal endoscopic disk surgery. The reasons may The most fearsome and shunned complications be due to a constellation of several conditions, of endoscopic spinal surgeries involve per- forming the intervention in regions adjacent to the carotid sheath in the anterior approach

Endoscopic Anatomy of Thoracic Spine 73 10 Endoscopic Anatomy of Thoracic Spine •Erkan Kaptanoğlu •Yahya Güvenç •Tunç Laçin •Toğrul Cavadov •Onur Erdoğan Disorders of the thoracic spine can originate cess the anatomical region around the spinal from a wide range of pathologies. For these cord according to the localization of the pa- pathologies, a broad spectrum of surgical ap- thology. Non-anterior approaches cause in- proaches are described in the literature in- adequate and difficult field of view and desta- cluding discectomy, vertebral body biopsy, cor- bilization of the posterior region.(1) Anterior pectomy, and tumor resection. Thoracoscopic approaches provide adequate and direct field spine surgery is a minimally invasive surgical of view for the spinal cord, but more frequent procedure. Thoracoscopic spinal procedures complications are seen due to the opening of have improved rapidly in the last 20 years. It the thoracic region and the pleural cavity.(2,3) is well documented that thoracoscopic spinal procedures are superior to thoracotomy in re- Approach to the spinal region by anterior gard to complications. Of all the spinal instru- thoracotomy has significant morbidity due to mentations, thoracic disc herniation occurs postoperative pulmonary problems, risk of in 0.5-4%. With endoscopy assisted surgery, major vessel injury, risk of mediastinal injury, both anterior and posterior approaches are and severe and prolonged postoperative pain. feasible for the thoracic spine. Transthoracic (4,5) Studies about thoracoscopic methods have anterior approaches have a wide range of dif- been performed to obtain the best surgical ferent interventions including multiportal vid- approaches and surgical techniques that will eo-assisted thoracoscopic surgery (VATS) and be maximally distant from the thoracic and full-endoscopic uniportal thoracic surgery. An mediastinal areas to avoid damaging them. understanding of surgical functional anatomy Posterior approaches such as transpedicular of the thoracic spine is necessary to achieve and costotransversectomy in thoracoscopic optimal surgical outcomes for thoracoscopic surgery allow an anterolateral image and an- surgery. terior neuroanatomy similar to thoracotomy. Thus, the minimally invasive method of thora- Spinal cord manipulation during spinal cord coscopic spinal surgery, which is distant from decompression should be avoided at the tho- the thorax and mediastinum, allows for mini- racic level. There are various anterior ap- mal anatomic damage.(6) proaches and non-anterior approaches to ac-

Thoracoscopic Discectomy 81 11 Thoracoscopic Discectomy •Ülkün Ünlü Ünsal •Ali Fahir Özer Introduction et al. published in 2015 contained 12 articles and 545 patients, in which 488 patients were Thoracic disc herniations (TDH) are seen less symptomatic. The authors divided the symp- frequently than cervical and lumbar disc her- toms into five main categories where the most niations.(1) Therefore, its treatment represents common was radiculopathy (39.5%), followed a rare practice in surgery, constituting 0.15- by myelopathy (19.4%), mixed (19%), low-back 1.8% of all surgically treated discs.(1-2) Wide- pain (12.1%), and multidimensional symptoms spread use of magnetic resonance imaging and (other pain symptoms, paresthesia, walking computerized tomography have also accompa- problems, paralysis, or weakness).(4) Wait et nied the increase in the prevalence of TDH. al., in their study of 121 cases published in While no gender difference exists, it peaks 2012, reported 15.7% had intestinal and uri- around 30-50 years of age. Three-quarters of nary symptoms, and 6.6% had only urinary cases occur at T7-8 levels and below, whereas symptoms apart from those mentioned above. only 4% are seen at the level of T3-4.(24-25) (5) Successful results have been obtained with conservative treatments such as non-steroidal Clinical Presentation anti-inflammatory drugs, epidural steroid ad- ministration, and physical therapy in most pa- Although conservative treatment can be used tients with simple radicular symptoms. in TDH patients without severe neurologic deficits, most patients still complain of thorac- Indications ic, paraspinal, intercostal, upper abdominal, and chest wall pain. Unfortunately, in some There is no consensus in the literature regard- patients, the diagnosis is delayed or misdi- ing the surgical treatment of TDH. However, agnosed until the symptoms of myelopathy some indications are almost common for all emerge. The study by Anand et al. in 2002 re- surgical techniques: intractable acute and/or ported a series of 112 patients who had under- persistent pain, progressive radicular, or cen- gone thoracoscopic discectomy due to TDH, tral neurological deficits. This group may be where they classified patients presenting extended by atypical symptoms.(6-8) The tho- symptoms into six grades and the most com- racic spinal cord is highly sensitive to anteri- mon symptom was significant axial and tho- racic radicular pain.(3) The review by Elham

Endoscopic Approaches to the Thoracic Spine/Percutaneous Endoscopic Thoracic Discectomy (PETD) 93 12 Endoscopic Approaches to the Thoracic Spine Percutaneous Endoscopic Thoracic Discectomy (PETD) •İsmail Bozkurt •Onur Yaman Introduction Most recent research reveals that PETD has similar or even better results compared with Thoracic disk herniations (TDH) with an inci- classical thoracic disk herniation surgery.(6) dence of 0.25-0.75% have a lower occurrence rate compared with cervical and lumbar disk PETD was used as an alternative to classi- herniations, thus reducing overall surgery cal surgery with significantly better results rate and surgeon experience. The first thora- in some series. Advantages such as local an- coscopic surgery was performed by Jacobaeus esthesia possibility, less post+operative pain, in 1910 for pleural adhesions.(1) But the first reduced para spinal and thoracic structure cases of TDH treated with thoracoscopy were damage, reduced epidural scar formation and performed by Mack et al. in 1993 and Rosen- the protection of stability renders this method thal et al. in 1994.(2,3) superior.(7) However, this technique requires a rigorous learning curve where a surgeon must In order to reduce intraoperative tissue dam- first be able to perform endoscopic lumbar age and postoperative surgical complications, discectomy without difficulty. Minor compli- percutaneous endoscopic thoracic discectomy cations such as insufficient discectomy or de- (PETD) was developed. Jho described an en- compression and major complications such as doscopic transpedicular thoracic discectomy neurovascular tissue damage, pulmonary con- method where he used an incision as small tusion, spinal cord injury and spondylodiscitis as 1.5-2 cm with 0- and 70 degree 5 mm en- must be kept in mind. PETD (percutaneous doscopes without the need for drainage placed endoscopic thoracic discectomy) encompasses in the thoracic wall.(4) In the year 2010, Chiu the title of the chapter Endoscopic Approach- described a posterolateral endoscopic thorac- es To The Thoracic Spine. ic discectomy where he used 0- degree 4 mm endoscopes along with low energy nonablative laser to perform thermodiscoplasty.(5)

Endoscopic Transpedicular Thoracic Discectomy 99 13 Endoscopic Transpedicular Thoracic Discectomy •Mesut Emre Yaman •Tolga Tolunay In the past, thoracic disc herniations were tra- Jho described endoscopic transpedicular tho- ditionally treated with a midline posterior lam- racic discectomy in 1997.(9) This procedure was inectomy. However, this procedure was very a pioneer in endoscopic thoracic spine surgery, dangerous due to postoperative spinal cord but his described technique using a 70°-lens injuries.(1) Consequently, over the years, the endoscope was very unfamiliar and had a very surgical treatment of thoracic disc herniation extended learning curve for most surgeons.(1) through midline posterior laminectomy has More recently the transforaminal approach to changed to more posterolateral approaches the thoracic disc was defined and is now more like costotransversectomy, lateral extra-cavi- common in use.(10,11) With improvements in tary and transpedicular approaches.(1,2,3) These equipment quality and the availability of high improvements reduced the risk of spinal cord definition camera systems, both of these pro- damage and catastrophic comorbidities which cedures are popular in clinics experienced in came with them. The need to increase access endoscopic spinal surgery worldwide.(1,8) to the ventral spinal cord brought the trans- thoracic anterolateral approach to the agenda. This chapter briefly describes the technical (4) Although this procedure provides direct ac- nuances of endoscopic transpedicular thoracic cess to the anterior aspect of the spinal cord, discectomy defined in the relevant literature. it is more invasive.(1,2,4) In the last years there has been an exponential increase in endoscop- (5,9) ic spinal surgery practice.(5,6) Parallel to these minimal invasive surgical procedures, access Indications to the thoracic spine for disc herniation was defined in several ways.(7) Video-assisted tho- The indications for this procedure are; often racoscopic surgery (VATS) and different vari- pain along the thoracic spine, with associated ations of this approach were defined.(8) Risks radicular symptoms in the chest wall, inter- of entering the thorax and an extended learn- scapular, thoracolumbar, intercostal area or ing curve are the limitations of this approach. the lower back also, numbness and paresthe- sia with an intercostal distribution related to (1,8) thoracic disc herniation and no relief in intrac- table symptoms after a minimum of 12 weeks of conservative management. The symptoms have to correlate with the magnetic resonance

Complications Associated with Endoscopic Thoracic Spinal Surgery 103 14 Complications Associated with Endoscopic Thoracic Spinal Surgery •Mehdi Sasani •Gülşah Öztürk Anesthesia, lung-related, patient position- and The reasons for complications can be divided surgical technique-associated complications into six main groups.(2) may be encountered in endoscopic spinal sur- gery. In a study reviewing endoscopic spinal 1. Anesthesia and Lung-related surgery techniques and the associated com- Complications plications, the overall complication rate was reported to be 42.3%. It was observed that Preoperative imaging and detailed physical intercostal neuralgia and peritoneal lacera- examination must be performed and pres- tions were rare, whereas intraoperative in- ence of any preexisting chronic disease, such tensive blood loss, postoperative respiratory as chronic obstructive pulmonary disease or problems, and transient nerve injury were Marfan’s syndrome which may lead to possi- common.(1) In another case series involving 90 ble respiratory complications, should be re- patients, this rate was reported to be 24.4%. searched. One lung is ventilated during sur- (2) In a case series of 29 patients who under- gery, and if the lungs are not ventilated in the went thoracoscopic discectomy, the compli- long term, it can lead to accumulation of secre- cation rate was reported to be 20%, whereas tions, causing atelectasis and pneumonia.(5) In in one series of 371 patients who were diag- order to prevent pneumonia and atelectasis, it nosed with thoracic and lumbar fractures and is recommended that the collapsed lung be in- underwent thoracoscopic decompression and flated at intervals of 5-10 minutes every hour fusion, it was reported to be 10.9%.(3,4) The during surgery.(6) Shortening the duration of complication rates vary depending on the un- surgery and preoperative and postoperative derlying pathology, type of surgical approach, pulmonary physiotherapy reduce the risk of and endoscopic-surgery experience of the sur- this complication. geon. Watanabe et al. reported that intensive bleeding and respiratory complications that 2. Patient Position-associated occurred during his first 4 years of experience Complications statistically decreased in the later stages, showing that the complication rate decreases Although the position of the patient varies ac- with surgical experience.(1) cording the location of the disease the patient is often placed in the right lateral decubitus position. This position permits operation from the left side and is less risky in terms of inju-

Endoscopic Anatomy of the Lumbar Spine 107 15 Endoscopic Anatomy of the Lumbar Spine •Göktuğ Akyoldaş Introduction The mamillary processes are small tubercles on the posterior-superior aspect of the superi- Embryologically, the lower half of a vertebra or articular processes of the lumbar vertebrae. and the upper half of the one below origina- They are located approximately a finger brea- te from the same segment. Between them is dth (2 cm) lateral to the midline at the level of the disc, which is partly a remnant of the no- the spinous process of the vertebra above and tochord. are not readily palpable. Surface Anatomy Osseous Anatomy Although identifying the appropriate verteb- Vertebral Body ral level for a percutaneous procedure can be easily accomplished by fluoroscopy, knowled- The vertebral bodies are large, with a trans- ge of the surface anatomy is necessary for a verse diameter greater than the anteroposte- better topographic orientation for surgery. rior diameter. The spinous processes of L4 and L5 are shor- Pedicles ter than the other lumbar spinous processes and are difficult to palpate, especially the L5 The two pedicles of a vertebra originate poste- spinous process. The spinous process of L4 is riorly and attach to the cranial half of the body the most inferior spinous process that has pal- (Figure 1). From L1 to L5, the pedicles beco- pable movement with flexion and extension of me shorter and wider, and are more lateral. the trunk. This situation widens the transverse diameter and narrows the anteroposterior diameter of Usually it is in a horizontal plane with the su- the spinal canal from above downwards. The perior margin of the iliac crests, although in shape of the normal bony spinal canal forms approximately 20% of the population the iliac an ellipse at L1, is a triangle at L3 and more crests are even with the spinous process of or less a trefoil at L5. L5.(1) Transvers Process The tips of the transverse processes of the lum- bar vertebrae are located approximately 5 cm la- The transverse processes originate from the teral to the midline and usually are not palpable. junction of pedicle and the lamina on the same

Transforaminal Endoscopic Discectomy 111 16 Transforaminal Endoscopic Discectomy •Hikmet Uluğ Introduction Positioning the spinal needle, and subsequent placement of the working cannula at the cor- Transforaminal endoscopic discectomy has rect site without complications during the in- progressed from being an “blind intradiscal tervention carries much importance. “Placing decompression” to a “target-oriented inter- at the correct site” means to approach the tar- vention”.(1-9) The basics of the target-oriented geted point from the correct entrance point intervention is the use of the foraminal win- at the correct angle; and positioning the nee- dow to reach the herniation or in other words, dle “to the correct site without complication” performing the intervention through the fo- sums up the process of reaching the targeted raminal opening. point or the correct site without damaging the surrounding neural structures and tissues in Accumulation of experience in performing the the retroperitoneal area. Careless handling transforaminal approach together with the of the spinal needle or wrong planning of the advances in surgical instruments have made trajectory to the targeted site may cause dam- it possible to expose neural structures such as age to the neural structures (i.e. cauda equina, the cauda equina, traversing and exiting nerve traversing and exiting nerve roots) along the roots and dissect the herniated tissue when path of the needle. necessitated. Thus, enabling the exposure and dissection of neural structures has advanced The stage reached after the placement of the transforaminal intervention to its current lev- working cannula is the “discectomy” stage. el which may be called the “exposition and dis- Disc herniation does not only involve the her- section” period. The common point of the last niation of nucleus pulposus. Also, fragmentec- two stages is the use of the foraminal window tomy may be performed. to reach the herniated tissue and the neural structures; in other words, conducting the in- “Herniation is defined as a localized displace- tervention through the foraminal way. ment of disc material beyond the limits of the intervertebral disc space. The disc material Transforaminal intervention can be evaluated may be the nucleus, cartilage, fragmented in three stages of application: Landing; the apophyseal bone, annular tissue or any com- needle and the working cannula placement, bination of them. The disc space is defined discectomy and the finishing the intervention. (10)

Posterolateral Endoscopic Lumbar Discectomy 129 17 Posterolateral Endoscopic Lumbar Discectomy •Ali Haluk Düzkalır •Salim Şentürk The posterolateral extraspinal approach to The learning curve for spinal endoscopy is lumbar disc herniations was first performed steeper than the traditional microscope-as- by Kambin et al. and Hijikata in 1973.(1,2) The sisted open procedures with or without the use Posterolateral Endoscopic Lumbar Discecto- of tubular retractors. The first barrier is the my (PELD) technique is mainly based with percutaneous approach itself. Selection of the Kambin’s transforaminal approach.(3,4) This right patient is important (Figure 1). The skin approach is used mostly for foraminal and entry point requires precise localization be- extraforaminal lumbar disc herniations. Also cause the narrowly-defined trajectory corri- migrated discs can be operated on with this dor leads to a small annular target surrounded approach.(5,6,7) PELD has several advantages by bony obstacles and neural elements deep over open discectomy, such as preservation within the body. The endoscopic cannula func- of normal paraspinal structures, rapid recov- tions as a retractor. The cannula bevel docks ery, minimal postoperative pain, low risks of into the annulotomy site in its entirety or in postoperative epidural scar formation and part. The second barrier is the lack of oper- decreased iatrogenic instability.(8,9,10) The pro- ating workspace once the surgical tools are at tection of facet joints is the main advantage the target. The surgeon has to match the view of using the PELD technique for extraforam- on the endoscopic monitor the patient’s real inal disc herniations. Additionally, PELD can proportions because of the magnified output be done under local anesthesia with real-time on the screen. The third learning barrier is the feedback about nerve injury and it also has actual need to operate multiple operating tools good cosmetic effect.(11) The placement of the using both hands and one foot simultaneous- initial punctures and following working chan- ly. Working comfortably while simultaneously nel are the most crucial factors for the surgical looking at a screen comes with a certain level success of PELD.(11) This procedure heavily of experience. relies on the surgeons’ experience and repeat- ed fluoroscopy, which may increase radiation Preparation for Surgery exposure and decrease the risk of nerve root injury. There are a lot of surgical tools needed for the PELD technique. The room must be prepared not only for the comfort of the surgeon but also to avoid contamination. C-arm fluorosco-

Interlaminar Endoscopic Discectomy 135 18 Interlaminar Endoscopic Discectomy •Altay Sencer •Ali Güven Yörükoğlu Lumbar disc herniations are a major cause of in the first half of 1980s, endoscopic lumbar back pain as well as radiating leg pain. Accord- discectomy techniques showed improvement. ing to North American statistics, about 85% of (4,5,22,23,24,25) Major improvements were achieved the population has experienced back pain with with the introduction of “Yeung Endoscopic or without leg pain, at least once in their life. Spine System (YESS)” by Yeung(26,27) and the (1-8) A small but significant portion of those pa- full-endoscopic interlaminar technique de- tients with major or progressive neurologic scribed by Ruetten.(28) Today, providing high- problems or who do not benefit from medical er postoperative patient comfort, endoscopic management are candidates for major or mi- lumbar discectomy has become a significant nor surgical procedures. Microsurgical discec- alternative to conventional MD in the manage- tomies are the main standard for major open ment of lumbar disc herniations. discectomies. Minor surgical procedures on the other hand, include nucleoplasties and fo- Various techniques were described, but main- raminal injections, laser discectomies and full ly, minimally invasive endoscopic approach- endoscopic interlaminar and transforaminal es to the lumbar spine can be classified into discectomies.(9-19) two major categories: transforaminal (TF) and interlaminar (IL). IL approaches can be In the last three decades, minimally invasive summarized as endoscopy assisted techniques endoscopic surgical techniques have been and full endoscopic techniques. Endoscopy widely adopted in different fields of medicine, assisted IL approaches were pioneered and with the evolution and refinement of the surgi- popularized by Destandeu (also called after cal endoscope. Minimally invasive procedures him). These systems were further developed to the lumbar spine date back to 1948, as Valls by various companies and are still used. But et al. described a percutaneous technique for their main disadvantage is that the operation aspiration biopsy in the diagnosis of vertebral is performed not through the working channel body lesions.(20) In 1970’s, Hijikata and Kam- of the endoscope but through tubular dilators bin separately defined a posterolateral ap- and the endoscope is used only for visualiza- proach for percutaneous central nucleotomy. tion, like the microscope. Therefore, these ap- (17,21) After the first visualization of interver- proaches are called “endoscopy assisted” and, tebral disc space with a modified arthroscope because the purpose of this chapter is to de-

Endoscopic Approaches to Lumbar Spinal Stenosis 143 19 Endoscopic Approaches to Lumbar Spinal Stenosis •Ülkün Ünlü Ünsal Introduction nosis. These endoscopic approaches provide a number of advantages including reduced Symptomatic degenerative lumbar spinal or tissue and muscle dissection, lower blood foraminal stenosis unresponsive to conserva- loss, reduced epidural fibrosis and scar tis- tive treatment is often treated by direct sur- sue formation, lower risk of instability, short- gical decompression. Conventional open lam- er hospital stays, early functional recovery, inectomy or foraminotomy performed with increased quality of life, and better cosmetic surgical decompression or fusion have been appearance. With precise indications, proper shown to be effective procedures. However, diagnosis, and good training, endoscopic spine conventional procedures may require resec- surgery can provide equally good outcomes as tion of the lamina, facet joints, and the spinous open spine surgery.(8) Although endoscopy ad- process following the dissection of paraspinal ministered for degenerative lumbar spinal or muscles, which in turn may increase the risk foraminal stenosis in select patients is still un- of segmental instability and adjacent segment der development, this procedure can be per- degeneration, infection, muscular atrophy formed with three approaches: secondary to excessive muscle dissection, and scar formation in neural structures and in the • Central stenosis approach epidural space and also involves an amount of blood loss, thereby increasing the complexity • Lateral recess approach of surgery particularly in patients requiring revision surgery.(1-7) Due to the probability • Foraminal stenosis approach of these complications, in line with the grow- ing use of minimally invasive spinal surgery Indications within the last decade and the development of high-technology optical devices, high-defini- • Radiculopathy or neurogenic claudication tion (HD) video recording systems, high-speed unresponsive to conservative treatment drills, and advanced spray-irrigation systems, (with or without back pain) minimally invasive fully endoscopic approach- es have become popular in select patients with • Severe stenosis accompanied by clinical degenerative lumbar spinal or foraminal ste- symptoms as verified with magnetic reso- nance imaging (MRI) and/or computed to- mography (CT) (Figure 1), (Figure 4).

Endoscopic Approaches to Various Spinal Pathologies 151 20 Endoscopic Approaches to Various Spinal Pathologies •Salim Şentürk Endoscopic techniques have been used and sensory deficits which require decompressive developed in spinal surgery for the last 30 surgery. years. Today the use of the endoscope is com- monly used in lumbar disc herniation and lum- In patients who underwent spinal instrumen- bar stenosis surgery. Advances in technology tation surgery screw malposition is reported and the increase in experience of the surgeons to be between 9-80%.(6) Screw malposition can in this field has led to an increase in the usa- result in a variety of symptoms from simple ge of endoscopic devices. Less intraoperative radicular pain up to limb paresthesia or seri- blood loss, decreased hospital stay, decreased ous motor deficits. Most authors recommend risk of complications of major classic surgery early revision surgery in patients who have and a smaller incision makes endoscopy more radicular symptoms due to screw malposition. preferable.(1) Currently, percutaneous spinal (7) Open surgery in which the leaked cement endoscopes have begun to be used for cement is removed and the trajectory of the screw is leakages, burst fractures, metastases and spi- changed lead to a wider laminectomy defect nal tumors. In this chapter we will demonst- and can cause dural or nerve root injury, CSF rate the use of the endoscope in various other leakage and complications secondary to it.(8) spinal pathologies with some case reports. The pedicle might be weakened so that the whole system needs to be elongated. Endos- Endoscopic Approach to Cement copic removal of the leaked cement is a fairly Leakage and Screw Malposition new surgical technique and might be approa- ched transforaminally, interlaminary or trans- In some patients with osteoporotic vertebra laminary.(9,10) Removal of the cement and/or fractures the use of vertebroplasty of kyphop- drilling of the portion of the screw in contact lasty is widely accepted. Despite being a mi- with the nerve root has to be kept in mind as nimal invasive procedure, cement leakage to an alternative in these patients. the spinal canal or the foramen are reported between 5-80%.(2-5) If the cement leakage is Case 1: 44-year old female patient with an os- observed intraoperatively open surgery might teoporotic vertebra fracture underwent ver- be indicated, if not noticed the patient might tebroplasty. Due to severe postoperative pain complain of post-operative pain or motor or in her left leg a lumbar CT was scheduled in

Complications of Endoscopic Lumbar Discectomy 167 21 Complications of Endoscopic Lumbar Discectomy •Kemal Paksoy •Ahmet Gürhan Gürçay In recent years, parallel to the development neural injury usually occurs to the descending of minimal invasive methods in spinal sur- nerve root, while in ELD procedures, ascend- gery, endoscopic lumbar discectomy (ELD) ing nerve root or dorsal ganglion damage is is becoming increasingly common for surgical more common which can manifest in postoper- treatment of lumbar disc hernias. As with any ative pain and dysesthesia. Neural injury may surgical procedure, ELD has its own gener- occur during insertion of needles, dilators, or al and unique complications. Complications in cannulas at the beginning of the procedure, general are similar to classic microdiscectomy or with excessive manipulation of surgical in- surgeries.(1-3) struments or thermal damage due to the light source used.(3,6-9) Recurrence Dura Mater Injury Recurrent disc herniation is reported to be 3.6% after ELD procedures, 4.2% after en- Dural injury is one of the rare complications doscopic interlaminar discectomy, and 3.4% of ELD surgery with an incidence reported after endoscopic transforaminal discectomy. as 0.8-3.3%. More often, mechanical rupture As with conventional microdiscectomy, obesi- due to the use of surgical instruments or ther- ty, young age, and type of herniation are risk mal damage due the illuminating light source factors for recurrence after ELD surgery.(4,5) are the leading causes. The amount of open or closed cerebrospinal fluid (CSF) fistula is Damage to Neural Structures, very small compared to microdiscectomy op- Transient and Permanent erations. However, if a CSF leak is observed Paresthesia during surgery, the defect can be repaired us- ing an atraumatic suture with the help of a mi- Damage to neural structures mostly appears cro-portege. In addition, dural adhesives, fat in the form of temporary paresthesia. While or muscle tissue grafts can be used to repair root injuries are seen at the rate of 0.7%, tran- dural defects. Small incision area and no/mini- sient paresthesia is seen in 4%. It develops mal muscle damage are the reasons why CSF depending on the needle and working cannula fistula are rare in ELD procedures.(3,10-12) used during the approach. In microsurgery,