Lumbar Degenerative Disc Disease and Dynamic Stabilization

By Dr. Ali Fahir Özer and Dr. Murat Coşar

PREFACE

Lumbar degenerative disc disease is one of the most discussed topics in spine surgery. The degeneration is a natural result of aging, and the etiology of the very common symptom, back and leg pain. Problems of diagnosis, indications and the type of surgery are still discussed.

This book “Lumbar Degenerative Disc Disease and Dynamic Stabilization” is a very well written text containing answers to those questions. The authors of the textbook stay on the side of dynamic fixation of the spine and find it a very valuable option for the treatment of degenerative disease in comparison to fusion surgery.

The authors are from Turkish spine surgeons and also well-known international names. I congratulate the editors Dr.Ali Fahir Özer and Dr.Murat Coşar for creation of this textbook and discussing that very challenging subject.

Mehmet Zileli, M.D.

Professor of Neurosurgery

Past President of the Turkish Neurosurgical Society

Past President of the World Spinal Column Society

Honorary President of the Middle East Spine Society

• Language: English
• Publisher: Dr. Ali Fahir Özer
• Release date: Jan 3, 2017
• ISBN: 9786055004071

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Dr. Ali Fahir Özer, Dr. Murat Coşar

Lumbar Degenerative Disc Disease and Dynamic Stabilization

ISBN: 978-605-5004-07-1

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Intro

1. THE DEVELOPMENT OF THE VERTEBRA AND THE INTERVERTEBRAL DISC

2. LUMBAR DISC DEGENERATION

3. BIOMECHANICS OF THE LUMBAR SPINE AND LUMBAR DISC

4. BIOMECHANICS OF DEGENERATIVE VERTEBRAL COLUMN AND SEGMENTAL-MULTISEGMENTAL INSTABILITY

5. DIFFERENCES BETWEEN OVERT AND CHRONIC INSTABILITY AND THE REFLECTION OF THESE DIFFERENCES IN TREATMENT

6. BIOMECHANICAL COMPARISON OF POSTERIOR DYNAMIC STABILIZATION WITH RIGID STABILIZATION

7. WHAT SHOULD BE THE IDEAL DYNAMIC SYSTEM?

8. CONTRIBUTIONS OF THE RIGID AND DYNAMIC SYSTEMS TO SPINE BIOMECHANICS: A PERSPECTIVE FROM FINITE ELEMENTS ANALYSIS

9. CONTRIBUTION OF LUMBAR DISC PROSTHESIS TO SPINE BIOMECHANICS AND FINITE-ELEMENT MODELLING

10. SAGITTAL AND CORONAL BALANCE IN THE SPINE

11. DEGENERATIVE DISC DISEASE IN THE LUMBAR SPINAL COLUMN

12. RADIOLOGICAL EVALUATION OF DYNAMIC INSTRUMENTATION

13. LUMBAR SEGMENTAL INSTABILITY

14. PHYSIOPATHOLOGY OF PAIN IN CHRONIC INSTABILITY

15. PATHOLOGIES OF CHRONIC INSTABILITIES

16. THE IMPORTANCE OF LUMBAR STABILIZATION EXERCISES AND SELECTED EXERCISE PROGRAMS

17. TREATMENT METHODS FOR LUMBAR PAIN AND THEIR MECHANISMS OF ACTION

18. DYNAMIC STABILIZATION AND SPORTS

19. HOW FAR HAS CLINICAL TREATMENT COME IN DEGENERATIVE DISC DISEASE?

20. STABILIZATION WITHOUT FUSION, WITH DYNESYS

21. MINIMALLY INVASIVE PAIN TREATMENT

22. ANESTHESIA IN SPINAL SURGERY

23. CHRONIC INSTABILITY AND FUSION SURGERY IN LUMBAR DEGENERATIVE DISC DISEASE

24. DISADVANTAGES, COMPLICATIONS AND TREATMENT OF FUSION SURGERY

25. HISTORICAL DEVELOPMENT OF FUSION, RIGID AND DYNAMIC INSTRUMENTATION

26. TEN YEARS EXPERIENCE IN DYNAMIC STABILIZATION

27. THE PHILOSOPHY OF DYNAMIC STABILIZATION

28. DYNAMIC STABILIZATION OF THE SPINE: A NEW CLASSIFICATION SYSTEM

29. INTERSPINOUS SPACERS

30. TOTAL DISC REPLACEMENT

31. UNILATERAL FACET JOINT REPLACEMENT: THE USE OF DYNAMIC SCREWS AND DYNAMIC ROD

32. ANTERIOR APPROACH TO LUMBAR SPINE

33. POSTERIOR DYNAMIC STABILIZATION IN CHRONIC INSTABILITY

34. TOTAL 325 DISC PROSTHESIS AND CLINICAL RESULTS OF POSTERIOR DYNAMIC SYSTEMS

35. PATIENT SELECTION IN LUMBAR NON-FUSION SURGERY

36. POSTERIOR PERCUTANEOUS TRANSPEDICULAR LUMBAR DYNAMIC STABILIZATION

37. ANTERIOR, POSTERIOR DYNAMIC SYSTEMS AND THEIR ADVANTAGES AND DISADVANTAGES

38. LUMBAR POSTERIOR HYBRID DYNAMIC STABILIZATION AND FUSION SYSTEMS

39. GENETIC APPROACHES AND BIOLOGICAL TREATMENTS IN DEGENERATIVE DISC DISEASE

40. THE FUTURE OF MOTION PRESERVATION SURGERY IN LUMBAR DEGENERATIVE SPINE DISEASES

Intro

Editor: Ali Fahir Özer

Co Editor: Murat Coşar

Publishers: Intertıp Yayınevi (Intertip publishing house)

Copyright©2016, Turkey

The scientific rights of this book and its contents belongs to the editors while rights pertaining to its printing, publication, distribution and sale belongs to İntertıp Publishers.

Unless written permission of the above mentioned persons and/or the publishers is obtained the whole or parts of this book cannot be reproduced and/or printed by means of mechanical, electronic, photocopying, magnetic paper and/or any other methods and cannot be distributed by any means or methods. Similarly, pictures, drawings and graphics contained in this book can not be used without permission of the publishers.

Editorial Coordinator: Hüseyin ÖZKAN

Project Coordinator: E. Armağan KARAAĞAÇLIOĞLU

Print-design-layout: İntertıp graphic workshop İZMİR

Date of Publication: 2016

Publisher Certificate number: KTB-22009

Print: Hermes Ofset Tanıtım

Printing the certificate number: KTB-14847

İntertıp Yayınevi (Intertip publishing house)

web site: www.intertipyayinevi.com

e-mail: [e-mail]

Customer service: [phone]

ISBN: 978-605-5004-07-1

Akgün, Enis M.D. Koc University, Faculty of Machinery Engineering, Istanbul - Turkey

Akman, Tarık M.D. Canakkale 18 March University, Faculty of Medicine, Department of Neurosurgery, Canakkale - Turkey

Alkan, Bahadır M.D. Canakkale 18 March University, Faculty of Medicine, Department of Neurosurgery, Canakkale - Turkey

Aras, Adem Bozkurt M.D. Canakkale 18 March University, Faculty of Medicine, Department of Neurosurgery, Canakkale - Turkey

Arık, Kasım M.D. Canakkale 18 March University, Faculty of Medicine, Department of General Surgery, Canakkale - Turkey

Artukluoğlu Feyzi M.D. VKV American Hospital, Department of Anesthesiology and Algology, Istanbul - Turkey

Asenjo, Juan Francisco M.D. Mcgill University, Health Center, Canada

Ataker, Yaprak M.D. VKV American Hospital, Department of Physical Therapy and Rehabilitation, Istanbul - Turkey

Aydın, Ahmet Levent M.D. 70. Year Physical Therapy and Rehabilitation Hospital, Department of Neurosurgery, Istanbul - Turkey

Aydın, Sabri M.D. Istanbul University, Cerrahpasa Medical Faculty, Department of Neurosurgery, Istanbul - Turkey

Bozdoğan, Çağlar M.D. Medeniyet University, Faculty of Medicine, Department of Neurosurgery, Istanbul - Turkey

Bozkuş, Hakan M.D., Ph.D. VKV American Hospital, Department of Neurosurgery, Istanbul - Turkey

Bulutçu, Erhan M.D. VKV American Hospital, Department of Anesthesiology and Algology, Istanbul - Turkey

Çalışaneller, Arif Tarkan M.D. Umraniye Education and Research Hospital, Department of Neurosurgery, Istanbul - Turkey

Calvosa, Giuseppe M.D. U.O. Ortopedia E Traumatologia. Ospedale Santa Maria Maddalena, Volterra, Italy

Canbulat, Nazan M.D. VKV American Hospital, Department of Physical Therapy and Rehabilitation, Istanbul - Turkey

Carilli, Senol M.D. VKV American Hospital Department of General Surgery, Istanbul - Turkey

Çavdar, Safiye M.D. Koc University, Department of Anatomy, Istanbul - Turkey

Çerezci, Önder M.D. VKV American Hospital, Department of Physical Therapy and Rehabilitation, Istanbul - Turkey

Coşar, Murat M.D., Ph.D. Canakkale 18 March University, Faculty of Medicine, Department of Neurosurgery, Canakkale - Turkey

Dalbayrak, Sedat M.D. Neurospinal Academy, Istanbul - Turkey

Dubois, Gilles G. M.D. Neurosurgeon Clinique De L’union Saint Jean, France

Düren, Rahşan M.D. VKV American Hospital, Department of Psychiatry, Istanbul - Turkey ul - rkey

Ece, Kubilay M.D. Avrasya Hospital, Department of Neurosurgery Istanbul - Turkey

Elias, Cimen M.D. Medeniyet University, Faculty of Medicine, Department of Neurosurgery, Istanbul - Turkey

Erbulut, Deniz U Ph.D. Koc University, Center of Manufacturing Automation and Research Center (MARC), Department of Mechanical Engineering, Istanbul - Turkey

Erçelen, Nesrin M.D. Istanbul Science University, Faculty of Medicine, Department of Medical Biology and Genetic, Istanbul - Turkey

Erçelen, Ömür M.D.

VKV American Hospital, Department of Anesthesiology and Algology, Istanbul - Turkey

Eser, Olcay M.D. Balıkesir University, Faculty of Medicine, Department of Neurosurgery, Balikesir - Turkey

Galgani, Matteo M.D. U.O. Ortopedia E Traumatologia. Ospedale Santa Maria Maddalena, Volterra, Italy

Gömleksiz, Cengiz M.D. Erzincan University, Faculty of Medicine, Department of Neurosurgery, Erzincan - Turkey

Gümüş, Terman M.D. VKV American Hospital, Department of Radiology, Istanbul - Turkey

Güven, Mustafa M.D. Canakkale 18 March University, Faculty of Medicine, Department of Neurosurgery, Canakkale - Turkey

Kaçar, Anıl Şafak M.D. Koc University, Faculty of Medicine, Istanbul - Turkey

Kaner, Tuncay M.D. Medeniyet University, Faculty of Medicine, Department of Neurosurgery, Istanbul - Turkey

Karaarslan, Öznur M.D. Canakkale 18 March University, Faculty of Medicine, Department of Neurosurgery, Canakkale - Turkey

Kiraz, Hasan Ali M.D. Canakkale 18 March University, Faculty of Medicine, Department of Anesthesiology and Reanimation, Canakkale - Turkey

Kömürcü, Erkam M.D. Canakkale 18 March University, Faculty of Medicine, Department of Orthopedics, Canakkale - Turkey

Lazoğlu, İsmail Ph.D. Koc University, Center of Manufacturing Automation and Research Center (MARC), Department of Mechanical Engineering, Istanbul - Turkey

Naderi, Sait M.D. Umraniye Education and Research Hospital, Department of Neurosurgery, Istanbul - Turkey

Nusran, Gürdal M.D. Canakkale 18 March University, Faculty of Medicine, Department of Orthopedics, Canakkale - Turkey

Öktenoğlu, Tunç M.D. VKV American Hospital, Department of Neurosurgery, Istanbul - Turkey

Okutan, M. Özerk M.D. Medicana Hospital, Department of Neurosurgery, Konya - Turkey

Özer, Ali Fahir M.D. Koc University, Faculty of Medicine, Department of Neurosurgery, Istanbul - Turkey

Özer, Erdinç M.D. Medipol University, Faculty of Medicine, Department of Neurosurgery, Istanbul - Turkey

Özkul, Faruk M.D. Canakkale 18 March University, Faculty of Medicine, Department of General Surgery, Canakkale - Turkey

Şafak, Özbey M.D. Canakkale 18 March University, Faculty of Medicine, Department of Neurosurgery, Canakkale - Turkey

Sarioğlu, Ali Çetin M.D. VKV American Hospital, Department of Neurosurgery, Istanbul - Turkey

Sasani, Mehdi M.D. VKV American Hospital, Department of Neurosurgery, Istanbul - Turkey

Şenol, Mehmet M.D. Medeniyet University, Faculty of Medicine, Department of Neurosurgery, Istanbul - Turkey

Solaroğlu, İhsan M.D. Koc University, Department of Neurosurgery, Istanbul - Turkey

Solmaz, Bilgehan M.D. Istanbul Education and Researh Hospital, Department of Neurosurgery, Istanbul - Turkey

Süzer, Tuncer M.D. VKV American Hospital, Department of Neurosurgery, Istanbul - Turkey

Tenucci, Miria M.D. U.O. Ortopedia E Traumatologia. Ospedale Santa Maria Maddalena, Volterra, Italy

Tura, Alper Ptr. VKV American Hospital, Department of Physical Therapy and Rehabilitation, Istanbul - Turkey

Ünal Kabaoğlu, Zeynep M.D. VKV American Hospital, Department of Radiology, Istanbul - Turkey

Vural, Metin M.D. VKV American Hospital, Department of Radiology, Istanbul - Turkey

Yazıcıoğlu, Tolga Ali M.D. VKV American Hospital, Department of General Surgery, Istanbul - Turkey

PREFACE

Lumbar degenerative disc disease is one of the most discussed topics in spine surgery. The degeneration is a natural result of aging, and the etiology of the very common symptom, back and leg pain. Problems of diagnosis, indications and the type of surgery are still discussed.

This book Lumbar Degenerative Disc Disease and Dynamic Stabilization is a very well written text containing answers to those questions. The authors of the textbook stay on the side of dynamic fixation of the spine and find it a very valuable option for the treatment of degenerative disease in comparison to fusion surgery.

The authors are from Turkish spine surgeons and also well-known international names. I congratulate the editors Dr.Ali Fahir Özer and Dr.Murat Coşar for creation of this textbook and discussing that very challenging subject.

Mehmet Zileli, M.D.

Professor of Neurosurgery

Past President of the Turkish Neurosurgical Society

Past President of the World Spinal Column Society

Honorary President of the Middle East Spine Society

1. THE DEVELOPMENT OF THE VERTEBRA AND THE INTERVERTEBRAL DISC

Safiye ÇAVDAR

P r e cartilage Stage (Mesenchymal S tage)

The vertebral column develops from the mesen- chymal cells that accumulate around the notochord during the 4th week of the embryonic period. At the end of the 4th week the mesenchymal cells that de- rive from the sclerotome of the somites accumulates in 3 major regions (1-3)

1.a . Region Surounding the N o t ochor d

In the 4th week of the embryonic period the sclerotomes accumulate around the notochord as paired mesen- chymal cells. Each of the sclerotome cells are grouped loosely at cranial and compact at caudal levels. Some of the dense cell groups migrate cranially and form the intervertebral disc. The rest of the dense cells group together with the caudal loose sclerotome forms the mesenchymal vertebral centrum. Each centrum is formed by two adjacent sclerotome and forms an intersegmental structure.

The nerves are closely related to the intervertebral disc and the segmental arteries which are closely lo- calized to the body side (corpus) of the vertebrae.

At the thoracic levels the dorsal intersegmental ar- teries are converted to intercostal arteries. The notochord around the developing vertebral body degenerates and vanishes. The notochord in between the vertebrae expands and forms the gelat- inous part of the intervertebral disc. This is called the ‘nucleus pulposus’. The nucleus pulposus is surrounded by regular circular fibers called the ‘annulus fibrosus’. The nucleus pulposus plus the annulus fibrosus form the intervertebral disc. Some remnants of the notochord may remain within the intervertebral disc which can result in ‘chordoma’. This neoplasm frequently occurs at the base of the skull and in the lumbosacral region (1-3).

1. b . Region Surrounding the Neural T ube

The mesenchymal cells in this region give rise to the vertebral arches.

1. c . Region Surrounding the C orpus

The mesenchymal cells in this region gives rise to the costal processes. The costal processes will give rise to the ribs in thoracic region (1-3).

2 . Cartilage S tage

In the 6th week of the embryonic stage the mesenchymal cells form the central cartilage of the vertebrae. At the end of this embryonic period the two centers of the centrum unite to form the cartilage centrum. At the same time the centrum of the arch of the vertebra unite with each other. The elongation of the cartilage centers of the arches forms the ‘spinous processes’ and ‘transvers processes’ (Figure 1).

3 . Ossification S tage

The typical vertebra ossification begins in this embryonic period and continues until 25 years of age (1-3).

4. Prenatal Stage

The centrum consists of two primary ossification cen­ters (ventral and dorsal). The two ossification centers unite to form a single center. At the end of this em­bryonic period 3 basic ossification centers develop. One of these is located at the centrum and the other two are located at the vertebral arches of each ver­tebra. The ossification of the arches become more prominent in the 81" week. At birth each vertebra is composed of 3 parts and each portion is connected to each other via cartilage

5.Postnatal Stage

The arch of each half of the vertebra fuses between 3-5 weeks. The fusion of the lumbar arches contin­ues until 6 years of age. First fusion takes place at the arches of the lumbar levels and then the lamina of the upper level vertebrae fuse. The union of the arches of the vertebrae with the centrum forms the neurocentral joint. These joints allow the enlarge­ment of the vertebral arches during development of the spinal cord (medulla spinalis). Between 3-6 years of age the union of centrum and the vertebral arch disappears.After puberty, 5 ossification centers are defined; one at the tip of the spinous process and two at the tip of the transverse process, two at the epiphysis (anular epiphysis). The two epiphysis, one is located superior and the other is located on the inferior surface of the body of the vertebrae (Fig­ure2). The superior and inferior surface of the body of the vertebrae is formed by anular epiphysis and in between there is a bony structure. The centrum is present in the body of the vertebrae, part of the vertebral arch and costal heads contain articular fac­ets. The secondary ossification centers ossify by the end of 25 years of age together with the vertebrae. The ossification age can show variations according to the individual. The secondary ossification cen­ters should not be confused with persistent epiph­ysis fractures

6. Variations in the Number of Vertebrae

Approximately 90% of the people have 12 thoracic, 5 lumbar, 5 sacral and 3-4 coccygeal vertebrae. In ap­proximately 3% there may be 1or 2 extra or fewer vertebrae (Figure2). The vertebral column should be evaluated as a whole because fewer vertebrae at one segment level can be compensated by extra verte­ brae at another segment level. For example the nwn­ ber of thoracic vertebrae may be 11, however the number of lumbar vertebrae may be 6 <4 ) (Figure 2).

Figure 1: Development of vertebrae and embryonic disc

a) Notochord, b) Nucleus pulposus and intervertebral disc, c) Mature intervertebral disc

Figure 2: Vertebral Column    Development Anomalies

7. Abnormal Development of the Vertebral  Column (Spina Bifida Occulta)

In the case of spina bifida the vertebral arches do not develop and do not unite on the mid-line. This congenital abnormality can occur in the form of total absence to partial absence of the vertebral arch (2,3).

1.a. General Vertebra Features

The vertebra, has a inner trabecular and outer compact bone structure. The compact part is thinner at the corpus and thicker at the arcus and processus part of the vertebra. The vertebral column is composed of 33 jointed vertebrae. Each vertebral column has 7 cervical, 12 thoracic, 5 lumbar, 1 sacral and 1 coccygeal vertebrae. The vertebral column supports the body and extremities and also has a strong elastic structure.

The stability of the vertebral column is achieved by the intervertebral disc, ligaments and the muscles. During movements of the vertebral column the function of the discs are to absorb shock. For this reason the shape and volume of the vertebrae changes according to the segmental level. A typical vertebra anteriorly is composed of a body and posteriorly an arch.

The projections extending posteriorly from the body are called the ‘pedicles’. The pedicles extending further posteriorly become flat and they are called ‘lamina’. The body, pedicle and lamina encircle a foramen called the ‘vertebral foramen’.

In an articulated vertebral column the vertebral foramen pile on top of each other and form a canal called the ‘vertebral canal’ (Figure 3a,b). Within this canal are located the spinal cord, meninx and the roots of the spinal nerves. Where the pedicle meets the lamina there are 3 pairs of processes called ‘superior articular processes,’ ’inferior articular processes‘ and ‘transverse process’. Where the two lamina meets there is a single process which extends posteriorly called the ‘spinous process’.

The superior articular process extends superiorly and has an articular surface on its posterior surface. This articular surface articulates with the articular surface of the inferior articular process of the vertebrae above. The inferior articular process extends inferiorly and has an articular surface on its anterior surface (⁵,⁶)

(Figure 3a,b). It articulates with the articular surface on the superior articular process of the vertebrae below. The movement (facet joint or zygapophysial joint) capacity of this joint is highly restricted and varies according to the vertebral level. 

The transvers process extends horizontally and it receives the attachments of the muscles which produce the rotation and lateral flexion of the trunk. The transverse processes of the thoracic vertebra has an articular surface which articulates with the ribs. The transverse processes are formed by the union of real transverse processes and costal elements (⁵,⁶) . When we view the vertebrae from the lateral side, pedicle and the superior articular process form a notch called the ‘ superior vertebral notch ’. Similarly, pedicle and the inferior articular process form another notch called the ‘ inferior vertebral notch ’ (Figure 3a,b). The inferior vertebral notch is deeper than the superior (⁵,⁶) . In an articulated vertebral column the inferior vertebral notch of the vertebra above and the superior notch of the vertebrae below forms a complete foramen called the ‘ intervertebral foramen ’. The roots of the spinal nerves exit from these foramina (Figure 3a,b).

Figure 3: Anatomy of lumbar vertebrae. a) Coronal b) Lateral

8. The Anatomy of the Lumbar Vertebrae

The number of lumbar vertebra varies from 5 to 6. The characteristic features of the lumbar vertebra is that they are very large compared to the rest of the vertebrae. They do not have articular surfaces on their transverse processes for articulation with the ribs and do not have a foramen in their transvers processes. The transverse diameter of the corpus of the lumbar vertebra are larger compared to the other vertebrae. The vertebral foremen of the lumbar vertebrae is triangular in shape and it is larger than thoracic but smaller than cervical vertebrae. The pedicles of the lumbar vertebrae are small. The spinous processes are directed horizontally and are quadrangular in shape. The superior articular processes of the lumbar vertebrae contain a concave articular facet on the posteromedial surface.

On the posterior surface of the superior articular processes is located the ‘mammillary process’. On the anterolateral surface of the inferior articular process is a convex articular facet (Figure 3a,b). The transvers processes of the 5th lumbar vertebrae (L5) are thinner and longer compared to the other vertebrae. At the base of the transverse process is a small bony spine called the ‘accessory process’ (Figure 3a,b). Measurements were made on the 3rd (L3) and 4th (L4) lumbar vertebrae of 338 female and males subjects, age ranged between 20 to 90. The results of these measurements showed that in male the width of the body of the vertebrae showed reduction related to age. In both sexes the anterior height of the body of the vertebrae showed reduction corresponding to the width reduction (⁷).

Twomey et al. (⁸) studied 93 adult vertebral columns and reported loss of bone density in the body of the lumbar vertebrae related to age. The loss in females was more pronounced compared to males. This loss can be due to the loss in the transverse trabecular bone. Amonoo-Kuofi (⁹,¹⁰) measured the distance between the two pedicles (the width of the vertebrae) and compared the results of 150 male and 140 female subjects. These results showed significant difference between male and female, however in nigerians it was constant in the two sexes. He concluded that the width of the vertebrae can show racial differences. Ratcliffe (¹¹) performed a detailed studied on the development of the body of the vertebrae from 29th prenatal week until 15 years of age. He reported that the transverse processes of 5th.

(L5) lumbar vertebra was the longest and the body was the largest among the lumbar vertebrae. Further, in order to contribute to the sacrovertebral angle the 5th lumbar vertebra is located more anteriorly compared to the rest of the lumbar vertebrae. To the anterior and posterior aspect of the body of the vertebrae is attached the ‘longitudinal ligament’. The crus of the diaphragm is attached to the anterolateral aspect of the longitudinal ligaments of upper lumbar vertebrae (3rd on the right, 2nd on the left). The psoas major muscle is attached to the sides of the body of all lumbar vertebrae. The vertebral canal of the 1st (L1) lumbar vertebrae contains the conus medullaris portion of the spinal cord, cauda equina and the meninx. Extending postero-laterally from the body is the paired pedicle. The superior vertebral notch of the lumbar vertebrae is shallow whereas the inferior vertebral notch is deep. The lamina of the lumbar vertebrae are large and short. The spinous processes do not overlap each other like the thoracic vertebrae. The thoracolumbar fascia, M.erector spinalis, M. spinalis thoracis, M. multifidus, M. interspinalis and interspinalis and supraspinous ligaments are attached to the spinous processes of lumbar vertebrae. The spinous process of the 5th (L5) is the smallest of the lumbar vertebrae and the tip of the spinous process is round and it is directed backwards. The distance between the two superior articular processes of the upper lumbar vertebrae is larger than the distance between the inferior articular processes. This difference between the distances reduces at the 4th lumbar vertebra (L4), and almost disappears at the 5th lumbar vertebra (L5). The articular surfaces on the superior and inferior articular processes are opposite (concave on the superior articular process and convex the inferior articular process) to one another. This joint allows a small amount of rotation, flexion and extension. Except for the 5th (L5) lumbar vertebra the transverse processes are flat extend dorsoventrally and elongates dorsolaterally (⁵,⁶). The lower border of the transverse processes of 5th (L5) vertebra is angulated, it extends more laterally then superolaterally. The angle at the lower border of the transverse processes represents the costal elements and its lateral ends represent the real transverse processes.

The transverse processes of 1st (L1) to 3rd (L3) lumbar vertebrae become larger from top to bottom. However, the transverse processes of 4th (L4) and 5th (L5) lumbar vertebrae are smaller. On the anterior surface of the tip of the transverse processes of lumbar vertebrae is a vertical line which attaches the anterior layer of the thoracolumbar fascia. To the medial aspect of this vertical line the psoas major muscle and to its lateral aspect the quadratus lumborum muscle are attached. The middle layer of the thoracolumbar fascia, the lateral and medial arcuate ligaments (lumbocostal arch) and the iliolumbar ligaments are attached to the tips of the transverse processes of the lumbar vertebrae. To the posterior surface of the transverse processes the muscular fibers of the deep back muscles and the longissimus muscles are attached. The lateral intertransversus muscles are attached to the lower and upper border of the transverse processes. The mammillary process is a homolog to the 12th superior tubercle of the 12th thoracic vertebra, to which the multifidus and the medial intertransversus muscles are attached. It is hard to define the accessory process, if present the medial intertransversus muscle is attached to it (⁵,⁶).

9. The Anatomy of the Lumbar Vertebrae Disc

There are a total of 23 intervertebral disc, 6 cervical, 12 thoracic and 5 lumbar discs (⁵,⁶). There are no intervertebral discs between atlas (C1), axis (C2) and between coccygeal vertebrae. The lumbar intervertebral disc in human subjects forms approximately one fourth of the length of the vertebral column. The lumbar intervertebral disc is approximately 7-8 mm thick and has a diameter of 4 cm. The shape of the intervertebral disc corresponds to the shape of the body of the vertebrae. The thickness of the intervertebral disc varies according to the segmental levels. Further, the thickness of the intervertebral disc shows regional differences within each disc. The intervertebral disc of cervical and lumbar vertebrae is anteriorly thick and posteriorly thin.

This structure increases the convexity of the vertebral column in the cervical and lumbar regions. The thickness of the intervertebral disc of the thoracic segments is even within the disc. The anterior concavity of this region is formed by the body of the vertebrae. The intervertebral disc at the upper thoracic levels are thin, while they are thickest at lumbar levels. The upper and lower surfaces of the intervertebral discs are covered with hyaline cartilage. Externally the intervertebral discs are composed of ‘annulus fibrosus’ and internally ‘nucleus pulposus’. The external (annulus fibrosus) portion of the intervertebral disc is supplied by the peripheral vessels. However, the internal portion is avascular and is supplied by diffusion from the trabecular bone of the body of the vertebrae. The reaction to trauma of the vascular and avascular portions of the intervertebral disc are different. The annulus fibrosus is attached to the edges of the body of the vertebrae and to the anterior and posterior longitudinal ligaments. The nucleus pulposus is attached to the hyaline joint cartilage. The nucleus pulposus absorbs the axial shocks and becomes flattened when squeezed. During flexion, extension and lateral flexion of the vertebral column the disc resembles a ball semi filled with liquid.

9.a. The Development of the Disc

Nucleus pulposus is derived from primitive notochord, while annulus fibrosus and the vertebrae are derived from the end plate. It is formed by proteoglycans, collagens and water in varying compositions. All intervertebral discs are attached to the anterior and posterior longitudinal ligaments. The intervertebral discs in the thoracic segments are also attached to the head of the rib laterally via intra-articular ligaments.

The Nucleus Pulposus

The nucleus pulposus is more developed in the cervical and lumbar segments. It is localized at the central and posterior surface of the disc (⁵,⁶). At birth it is composed of soft gelatinous and mucoid material. It can possess a few notochord cells and fibers from the annulus fibrosus. Later in development the notochord cells disappear and in time the mucoid material develops into the hyaline cartilage. With increasing age the nucleus pulposus cannot be separated from the rest of the disc reduces and becomes less hydrated and more fibrous in structure. Cross bandings are formed between collagen and the proteoglycan. Also reduces the water holding capacity of the discs and becomes harder and more vulnerable to trauma (Figure 4). The nucleus pulposus is in the form of gelatinous structure and it is under high pressure in sitting position. It has a function of transferring the load in an axial direction and in lower body movements it acts as the movement axis. The third function is to act like a ligament to hold the vertebrae together.

Figure 4: Anatomy of intervertebral disc

Annulus Fibrosus

Annulus fibrosus is more fibrous and has less water and more collagen than the nucleus pulposus (⁵,⁶). It surrounds the nucleus pulposus which is under high pressure and holds it in the appropriate position (Figure 4). Annulus fibrosus is composed of approximately 15-25 collagen rings and are called ‘lamella’. Between these lamellar structures are located elastin fibers. These elastin fibers support the disc during bending. These lamellar fibers are aligned parallel to each other and aligned vertically forming 65⁰ between vertebrae. The vertical fibers may be loose on the posterior aspect and may be vulnerable to trauma. This standard structure of the annulus fibrosus may not be present in all levels of the vertebral column (Figure 5).

Figure 5: Intervertebral disc herniation

9.b. The Arterial Supply of the Intervertebral Disc

It is supplied by 2 sources: First is by way of bone marrow diffusion from small foramina located on the hyaline cartilage overlying the body of the vertebrae and the second source is by way of diffusion from peripheral blood vessels. Due to the two different structures of the intervertebral disc their reactions to trauma are different (¹¹).

10. The Ligaments of the Vertebral Column

The ligaments of the vertebral column are divided into 3 groups; external craniocervical, internal craniocervical and vertebral ligaments.

10.a. External Craniocervical Ligaments

These ligaments connect cranium to the atlas (C1) and axis (C2). These ligaments are quite loose so that the cranium can move freely (⁵,⁶).

The Anterior Atlantooccipital Membrane

The anterior atlantooccipital membrane extends between the upper borders of the anterior arch of the atlas and the anterior border of the foramen magnum. It is a thick fibroelastic membrane. Laterally this ligament is continues with the capsule of the atlantooccipital joint. Anteriorly this ligament is strengthened by the course of the anterior longitudinal ligament (⁵,⁶).

The Posterior Atlantooccipital Membrane

This larger and thinner than the anterior atlantooccipital membrane. It extends between the upper borders of the posterior arch of the atlas and the posterior border of the foramen magnum. This membrane on each side arches over the vertebral artery and forms an opening for the course of the vertebral artery towards the atlas and for the exit of the 1st (C1) cervical spinal nerves (⁵,⁶).

Joint Capsule

The joint capsule extends between the condyles of the occipital bone and superior articular facets of the atlas. The capsule is quite loose and allows the movement of the head. The joint capsule is thin at the center and thick at the sides. The thickening on the sides is also called ‘lateral atlantooccipital ligament’. The lateral atlantooccipital ligament restricts the lateral flexion of the head.

Anterior Longitudinal Ligament

The anterior longitudinal ligament extends from the base of the skull to the sacrum (Figure 6). The upper part of this ligament medially supports the anterior atlantooccipital membrane in the midline. The part between the anterior tubercle of the atlas and the anterior median ridge on the axis have lateral extension called the ‘atlantoaxial’ ligament (epistrophic ligament).

Nuchal Ligament

The nuchal ligament a fibroelastic membrane which extends between the external occipital protuberance of the occipital bone and the posterior tubercle of atlas and spinous processes of cervical vertebrae. This ligament forms a septum in the midline and provides muscle attachments (⁵,⁶).

Ligamentum Flavum

This a yellowish elastic membrane that extends between the lamina of two neighboring vertebrae. It extends between the posterior arch of the atlas and the lamina of the axis. It is absent between the atlas and the occipital bone (⁵,⁶) (Figure 6).

10.b. Internal Craniocervical Ligaments

Internal craniocervical ligaments are located at the posterior surface of the body of the vertebrae. They strengthen the craniocervical region and prevent the extensive movements of the head. They restrict the medial and lateral rotation of the head around the atlantoaxial joint (⁵,⁶).

Tectorial Membrane

Tectorial membrane is located within the vertebral canal. It is the upper continuation of the posterior longitudinal ligament. It extends from the posterior surface of the body of the axis to the anterior and lateral edge of the foramen magnum, and superiorly blends with the dura mater. The tectorial membrane added to the other ligaments has a supportive function for the spinal cord and medulla oblongata (⁵,⁶).

Transverse Ligament of Atlas

Transverse ligament of atlas is a strong ligament passing transversely posterior to the dense of the axis. On each side, it attaches to the ‘tubercle’ on the medial aspect of the lateral mass of the atlas. From the midpoint of the dense it extends upwards and downwards to the base of the occipital to be fixed respectively, to the basilar part of the occipital bone between the tectorial membrane and the apical ligament of the dense and the posterior surface of the body of the axis- the superior and inferior longitudinal fascicles. The transverse and the vertical bands are collectively called the ‘cruciform ligament’ (⁵,⁶).

Apical Ligament

The apical ligament extends from the apex of the dense to the anterior mid portion of the foramen magnum. It extends between the atlantooccipital membrane and the superior longitudinal fibers of the cruciform ligament.

Alar Ligament

The alar ligament extends upwards and laterally from the superolateral aspect of dense to the medial surface of the condyles of the occipital bone. It controls the excessive rotation around the atlantooccipital joint.

Accessory Ligament

It extends from the base of the dense to the lateral masses (close to the attachments of the transverse ligament) of the atlas. It restricts the excessive rotation around the atlantoaxial joint.

10.c. Vertebral Ligaments  Anterior Longitudinal Ligament

This is a band-shaped ligament extending between the anterior tubercle of the atlas and sacrum. It becomes wider from top to bottom. The anterior longitudinal ligament is closely attached to the anterior surface of the body of the vertebrae and to the intervertebral disc during it’s course. It is composed of superficial and deep fibers. The short fibers connect the neighboring two vertebrae and the intervertebral disc, whereas long fibers connect several vertebrae. The anterior longitudinal ligament is thickest in the at thoracic segment. This ligament prevents the hyperextension of the vertebral column (Figure 6).

Posterior Longitudinal Ligament

The posterior longitudinal ligament is wide at upper vertebral levels and narrow at the lower segments of the vertebral column. It is located at the posterior aspect of the body of the vertebrae within the vertebral canal. It extends between the axis and the sacrum. The upper portion of the posterior longitudinal ligament is continues with the tectorial membrane. The sides of the posterior longitudinal ligament specially in thoracic and lumbar regions extends laterally and fuses with the annulus fibrosus fibers of the intervertebral disc. Between the posterior longitudinal ligament and the posterior surface of the body of the vertebrae is located the basivertebral vein. The posterior longitudinal ligament prevents the hyperflexion of the vertebral column (⁵,⁶) (Figure 6).

Ligamentum Flavum

Ligamentum flavum connects two neighboring lamina of the vertebrae. It extends between the anteroinferior border of the lamina of the vertebra above and the posterosuperior border of the lamina of the vertebra below. The medial aspect of the ligament contains openings for the exit of the external and internal venous plexus. The thickness of the ligamentum flavum increases from cervical to lumbar levels (⁵,⁶) (Figure 6).

Supraspinal Ligaments

Supraspinal ligaments extend between the spinous processes of 7th (C7) cervical vertebra to the sacrum. The supraspinal ligaments superiorly continue with the ligamentum nuchae, anteriorly with the anterior interspinal ligaments. The thickness of the supraspinal ligaments increases from cervical to lumbar levels (⁵,⁶) (Figure 6).

Interspinous Ligaments

Interspinous ligaments fill the space between two spinous processes. The interspinous ligaments are most developed at lumbar levels (⁵,⁶) (Figure 6).

Intertransverse Ligaments

Intertransverse ligaments fill the space between two transverse processes. This ligament is in the form of filamentous structure at lumbar levels, however, at thoracic levels it is in the form of dense thick bands (⁵,⁶) (Figure 6).

Figure 6: Ligaments of vertebral column

10.d. Ligaments of the Coccyx and Sacrum  Ventral Sacroiliac Ligament (Anterior Sacroiliac Ligament)

It arises from the pelvic and alar surface of the sacrum and attaches to the ileum. This ligament is thin and fibrous in structure and has a function of strengthening the joint capsule.

Dorsal Sacroiliac Ligament (Posterior Sacroiliac Ligament)

It extends on the dorsal surface. Superficially it is composed of long and deep ligamentous bundles. The long superficial bundles of the sacroiliac ligament extends from the posterior superior iliac spine and attach to the lateral aspects of 3rd and 4th sacral segments. The fibers of this ligament which are externally located fuses with the sacrotuberous ligament. The deep short fibers of the dorsal sacroiliac ligament extend from the medial surface of the ileum and attaches to the lateral surface of the 1st and 2nd sacral vertebrae. The deep short fibers of the dorsal sacroiliac ligament are also called ‘interosseous ligament’.

Interosseous Sacroiliac Ligament

This is composed of short thick fiber bundles. It extends between the tubercles of the ileum and forms a firm band between the two bones. It is located deep in the dorsal sacroiliac ligament and is one of the strongest ligaments within the body.

Sacrotuberous and Sacrospinous Ligaments

Sacrotuberous and sacrospinous ligaments are accessory ligaments of the sacroiliac joint. Both ligaments assists the movements of this joint. Anterior, dorsal and lateral sacrococcygeal ligament binds the sacrum to the coccyx.

11. Joints of the Vertebral Column

The joint between the bodies of the vertebrae between C2 and S1 are cartilaginous. The joint between articular processes are synovial type (zygapophyses) and the joint between the lamina, transverse processes and spinous processes are fibrous type.

11.a. The Joint Between the Body of the Vertebrae

The bodies of the vertebrae articulate with the anterior, posterior longitudinal ligament and the fibrocartilaginous intervertebral discs.

11.b. Facet (Zygapophyseal) Joint

This joint is located between the superior and inferior articular process. This joint is also called the zygapophyseal joint. The articular surfaces are flat and covered with hyaline cartilage. The facet joints have thin articular capsule. These capsules are long and loose in the cervical region compared to thoracic and lumbar levels. This enables the cervical levels to produce a large amount of flexion and extension. The facet joints of the cervical and lumbar vertebrae together with the intervertebral disc has a function of carrying weight. Further, they control the flexion, extension and rotation movements of the cervical and lumbar levels. The facet joints are innervated by the medial branches of the dorsal ramus of the spinal nerve.

11.c. Atlantooccipital Joint

This is the joint between the lateral masses of the atlas and the condyle of the occipital bone. The articular surface of the atlas is concave and sometimes this articular surface is divided into two. The joint capsule enclosing the two bones fuse with the anterior and posterior atlantooccipital membrane. The nodding movement of the head is achieved by this joint.

11.d. Atlantoaxial Joint

There are two synovial joints between the atlas and axis. The lateral atlantoaxial joint is a plane type of joint, located between the atlas and the body of the axis. It is located between the inferior articular surface of the atlas and the superior articular surface of the axis. The medial atlantoaxial joint is located between the anterior arch of the atlas and the dense of the axis and it is a pivot type joint.

11.e. Lumbosacral Joint

Lumbosacral joint is located between the 5th (L5) lumbar and the 1st (S1) sacral vertebrae and the intervertebral disc. Lumbosacral joint is supported anteriorly and posteriorly by the anterior and posterior longitudinal ligament. Additionally, the 5th (L5) lumbar vertebra is connected to the ileum and sacrum by the iliolumbar ligament.

11.f. Sacrococcygeal Joint

Sacrococcygeal joint is located between the apex of the sacrum and the base of the coccyx. It is composed of lateral, dorsal and ventral ligaments.

12. Curvature of the Vertebral Column

The vertebral column in the male is approximately 70 cm and in the female is 60 cm in length. Twelve cm is cervical, 28 cm is thoracic, 18 cm lumbar and 12 cm is sacral and coccygeal. The vertebral column anteroposteriorly consists of 4 curvatures. When the vertebral column is viewed from anterior the thoracic and sacral segments are concave and cervical and lumbar segments are convex. The thoracic and sacral curvatures develop in the embryonic period and are called ‘primary curvatures’ (Figure 7). Cervical and lumbar curvatures develop in the fetal period, become prominent childhood and are called ‘secondary curvatures’ (Figure 7). The cervical curvature develops when the child keeps the head erect and the lumbar curvature develops when the child starts walking. Abnormal development of the curvature results in excessive kyphosis, lordosis and scoliosis.

Figure 7: Vertebral column curves

13. Movement of the Vertebral Column

The movements of the vertebral column are achieved by the nucleus pulposus of the intervertebral disc and the facet joints. Although the capacity for movement of the vertebrae are highly restricted by the ligaments, various movements occur around these joints. The cervical and lumbar portions of the vertebral column are the most mobile portions. The vertebral column can produce flexion, extension, lateral flexion, rotation and circumduction.

13.a. Flexion Movement

The anterior longitudinal ligament relaxes and the posterior longitudinal ligaments, ligamentum flavum, interspinous and subspinous ligaments produce flexion as much as these ligaments allow. At the same time the anterior border of the intervertebral disc is compressed the distance between the lamina increases and the superior articular processes glide on the inferior articular processes. The tension of the extensor muscles are important in limiting the flexion movement. Cervical segments can produce extensive flexion.

13.b. Extension Movement

Exactly the opposite events occur in the case of extension movement. The anterior longitudinal ligament contracts, posterior borders of the intervertebral disc are compressed, the distance between the spinous processes decreases. The extension movement is present at cervical and lumbar segments. At thoracic levels due to the thin intervertebral disc and inappropriate muscular and skeletal structure a limited amount of extension occurs.

13.c. Lateral Flexion Movement

During lateral flexion the intervertebral disc of one side compresses while the other side extends. The antagonist muscles and ligaments limit lateral flexion. Lateral flexion can occur together with rotation. Lateral flexion can occur at cervical and lumbar levels.

13.d. Rotation Movement

This movement occurs by the rotation of the vertebral bodies one on top of the other. Most of the rotation occurs at upper thoracic levels while least rotation occurs at the cervical and lumbar level.

13.e. Circumduction Movement

This is limited movement of the vertebral column. It is the combination of flexion, lateral flexion and extension movements (⁵,⁶).

14. Muscles Producing Movements of the Vertebral Column

The movements of the vertebral column are produced by 2 groups of muscles. The first group of muscles are the ones that are attached directly to the vertebral column; they are called ‘intrinsic muscles’. The second group of muscles are attached to the bony structures other than the vertebral column, these muscles indirectly assist the movement of the vertebral column and are called ‘extrinsic muscles’.

The flexion movement is achieved by M. longus coli, M. sternocleidomastoid and M. rectus abdominus muscles. The extension movement is achived by M. erector spinalis, M. splenius, M. semispinalis capitis and M. trapezius muscle (⁴,⁵) (Figure 8).

Figure 8:  The muscles of the vertebral body and the posterior element, allow movement of the vertebral column in three planes. Movements of vertebral column:Flexion, extension, rotation

15. Arterial Supply and Venous Drainage of the Lumbar Vertebrae

15.a. The Arterial Supply

The vertebral column and the soft tissue is supplied by the dorsal ramus of the embryonic intersegmental somatic arteries (¹¹,¹²) (Figure 9). Thoracic segments are supplied by posterior intercostal arteries of the descending aorta. The abdominal segments are supplied by lumbar arteries from the abdominal aorta. Both lumbar arteries surround the body of the vertebrae and have periosteal and equatorial branches. These arteries also divide into dorsal branches and from the dorsal branches arise spinal branches. The spinal branches enter through the intervertebral foramen and supply the facet joints, posterior surface of the lamina, muscles, skin and subcutaneous tissue (¹¹-¹⁴) (Figure 9). At cervical and sacral segments there are longitudinally oriented spinal arteries. These spinal arteries supply the bony vertebrae, dura and epidural structures. Additionally, the radicular arteries supply the spinal cord and roots of the spinal nerves (Figure 9). The spinal arteries entering vertebral canal divide into postcentral, prelaminar and radicular arteries. The postcentral branch supplies the surface of the vertebra body and the intervertebral disc and anastomosis with similar arteries of the opposite side. This artery also supplies the anterior epidural tissue and dura (Figure 9). The posterior vertebral arch, posterior epidural tissue, dura, posterior wall of the vertebral canal and ligamentum flavum are supplied by prelaminar and anastomotic branches (¹¹-¹⁴).

15.b. Venous Drainage of Lumbar Vertebrae

The venous drainage of the vertebral column is via external and internal venous plexus which extends throughout the vertebral column (¹¹-¹⁴). There are no valves in both external and internal venous plexuses. Both external and internal venous plexuses anastomose with each other and drain into the intervertebral veins. In the early fetal period, the external and internal venous plexuses connect with the longitudinal veins. After the completion of development, these plexuses drain into the caval and lumbar azygos system. These veins are also connected to the cranial venous sinuses, deep veins of the neck and pelvis (¹¹-¹⁴). The veins of the vertebral column have a large amount of dilatation capacity. Further, patients with major obstruction of the thoracic and abdominal veins can develop alternative drainage pathways. Because there are no valves, the malign diseases or sepsis can spread to large areas. The pressure difference in the body cavities can be conveyed to the cerebrospinal fluid (CSF) via the venous plexuses. However, the spinal cord can protect itself from this kind of congestion by the small veins that drain into the internal venous plexus.

16. The External Vertebral Plexus

The external vertebral plexus is divided into anterior and posterior groups. These veins have free anastomosis and are mostly developed at cervical levels (Figure 9). The anterior external vertebral plexus located at the anterior aspect of the body of the vertebrae. They are connected to the basivertebral and intervertebral veins. They drain the venous blood from the body of the vertebrae. The posterior external vertebral plexus is located at the posterior aspect of the vertebral lamina, spinal processes, transverse processes and the articular processes. They have anastomosis with the internal venous plexus. It has connections with the vertebral veins, posterior intercostal vein, and lumbar vein.

17. The Internal Vertebral Plexus

The internal vertebral plexus is located between the dura mater and the vertebrae. It collects the venous blood from the bone marrow and the spinal cord (Figure 9). The external plexus is more dense. There are 4 vertical coursing longitudinal veins (2 anterior and 2 posterior), which have interconnections with each other. The anterior external plexus is large venous plexus located on the posterior surface of the body of the vertebrae and the intervertebral disc. These veins drain into the basivertebral veins via the transverse veins. The posterior internal plexus anastomoses with the external plexus. The internal venous plexus forms a ring around the vertebrae and anastomoses with itself. It is connected to the vertebral vein around the foramen magnum, occipital and sigmoid sinus, basilar plexsus, venous plexus around the hypoglossal canal and emissary veins (¹¹-¹⁴).

17.a. Basivertebral Veins

The basivertebral veins are located within the bone and are similar to the diploic veins of the cranium in having a tortuous structure (¹¹-¹⁴). They exit through the small foramen located in the body of the vertebrae and drain into the anterior external vertebral plexus located within the vertebral foramen

(Figure 9). They form one or two trunks that connect the posterior transverse and anterior internal vertebral plexus. The basivertebral veins show dilatations in old age.

17.b. Intervertebral Veins

The intervertebral veins accompany the spinal nerves within the intervertebral foramen. They collect the venous blood from the internal and external vertebral plexus and drain into the posterior intercostal vein, lumbar vein and lateral sacral vein (Figure 9). In the upper levels; the posterior intercostal veins drain into the brachiocephalic veins then to the cava system; the intercostal veins of the lower levels drain into the azygos system. The lumbar veins drain into the ascending lumbar veins which course longitudinally on the anterior surface of the transverse processes. They may sometimes encircle the body of the vertebrae and drain into the inferior vena cava. It is not known whether the basivertebral and the intervertebral veins have active functioning valves. Experimental research has shown that the blood can flow in a backward direction. This explains how prostate cancer or pelvic neoplasm can cause metastasis to the body of the vertebrae. The cancer cells can spread by the connections of the internal vertebral plexus with the pelvic veins. Due to postural changes or an increase in the intraabdominal pressure reverse flow of the blood may occur and result in spread of the cancer cells.

Figure 9: Arterial supply and venous drainage of lumbar vertebrae

17.c. Lymphatic Drainage

The lymphatic vessels drain into the deep lymphatic vessels which accompany the arteries. The cervical portion of the vertebral column drains into the deep cervical lymph nodes, thoracic portion to the posterior intercostal lymph nodes and lumbar portion into the lateral aortic or retroaortic lymph nodes. The pelvic portion of the vertebral column drains into the lateral sacral and internal iliac lymph nodes (¹¹-¹⁴).

17.d. Innervation of the Vertebral Column

The innervation of the vertebral column and the soft tissue surrounding it at lumbar levels is via segmental spinal nerves. Also, branches from the gray ramus communicans of the thoracic sympathetic ganglia supplies the sympathetic innervations. Important nerve fibers innervating the vertebral column are dorsal ramus of spinal nerve, recurrent branches from the meningeal branches and from sinuvertebral nerves.

References

1- Hamilton WJ, Mossman HW: Human embryology. (4th ed), Williams and Wilkans 1972, pp 437, 526

2- Moore K: The developing human. (4th ed), WB Saunders, 1988, pp 334-340, 364-401

3- Wendel CP, Williams PL, Treadgold S: Basic human embryology. (3rd ed), Pitman Pub Ltd, 1984, pp 102-143

4- Standring S: Gray’s anatomy: The anatomical basis of clinical practice. (2nd ed), Churchill Livingston, 2008, pp 723-728

5- Williams P, Warwick R, Dyson M, Bannister LH: Gray’s anatomy. (37th ed), Chur-Chill Livingstone Longmann Group, 1989, pp 315-489, 919-948

6- Netter FH: The Ciba collection of medical illustrations. CIBA Pharma, Vol 1, 1983 pp:11-20

7- Ericksen MF: Some aspects of aging in the lumbar spine. Am J Phys Anthropol 45:575-580, 1976

8- Twomey L, Taylor J, Furniss B: Age changes in the bone density and structure of the lumbar vertebral column. J Anat 136:15-25, 1983

9- Amonoo-Kuofi HS: Maximum and minimum lumbar interpedicular distance in normal adult Nigerians. J Anat 135:225-233, 1982

10- Amonoo-Kuofi HS: The sagittal diameter of the lumbar vertebral canal in normal adult Nigerians. J Anat 140:69-78, 1985

11- Ratcliffe FF: Arterial anatomy of the developing human dorsal and lumbar vertebral body: A microarteriographic study. J Anat 133:625-638, 1981

12-  Carpenter MB: Core text of neuroanatomy. (3 rd ed), Williams Wilkins, 1985, pp 53-95

13- Afifi AD, Bergman RA: Basic neuroscience. (2nd ed), Urban, Schwarzenberg Inc, 1986, pp 43-91

14- Snell RS: Clinical neuroanatomy for medical students. (2nd ed), Boston, Little, Brown and

2. LUMBAR DISC DEGENERATION

Ali Çetin SARIOĞLU, Tuncay KANER, Çimen ELIAS

Vertebral degeneration is a process that also includes degeneration of bony and ligamentous structures. Vertebral corpus, facet articulations, intervertebral discs (IVD) and ligaments are the structures affected. Concordantly degeneration related to the vertebral column aging process and vertebral column degeneration disease must be distinguished. In clinical evaluation, there are no certain symptoms to distinguish the aging process from degenerative disease. Nevertheless to understand the natural aging process of the vertebral column as a systematic process, it is also important to understand lumbar disc degeneration pathophysiology. Biomechanical and biochemical changes play a role in IVD degeneration including intrinsic, extrinsic and genetic factors. Compression and torsional injuries of the vertebral column, excessive pressure and congenital anomalies cause excess pressure on IVD. In addition to these factors atherosclerosis, vascular disease, anemia, immobilization, diabetes and tobacco usage increase disc degeneration. The best known and most important reason for chronic low back pain is IVD degeneration.

As is well-known degenerative disc disease is thought to be the primary reason for instability in vertebral segments. Finally in degenerative disc disease segmental instability was found to be responsible for low