Lumbar Spine Flashcards
What are the 4 regions of curvature in a normal adult spine?
- Cervical lordosis
- Thoracic kyphosis
- Lumbar lordosis
- Sacrococcygral kyphosis
What is responsible for the permanent thoracic kyphosis?
The thoracic vertebral bodies are greater in height posteriorly than anteriorly.
How do vertebral bodies compensate for scoliosis?
They undergo rotation so that the spinous processes face the concavity of the curvature.
In erect posture the sacrum tilts forward which can cause L5 anterior displacement (slipping) on the sacrum, what factors help to prevent/limit this slipping?
- The L5 inferior facet faces anteriorly and the S1 superior facet faces posteriorly.
- Ligamentous support from supraspinous and interspinous ligaments.
- The iliolumbar ligament attaches the transverse processes of L5 to the ilium, anchoring L5 in place.
- The anterior longitudinal ligament also prevents anterior displacement
What is an idiopathic scoliosis?
This is a lateral curvature of the spine which develops spontaneously with no clear cause.
What are potential causes of postural/functional scolioses?
- Leg length discrepancies
- Muscle spasms
- Degenerative changes in intervertebral discs or apophyseal joints
- Osteoarthritic changes in the knee and hip
What classifies as anterior pelvic tilt?
This is when the vertical place of the ASIS is anterior to the vertical place of the pubic symphysis.
What classifies as posterior pelvic tilt?
This is where the vertical plane of the ASIS is posterior to the vertical plane of the pubic symphysis.
What classifies as lateral pelvic tilt?
This is where the iliac crest is higher on one side than another.
How many bony segments are there in the vertebral column?
33
How are the 33 bony segments of the vertebral column divided?
24 bones are mobile segments (7 cervical, 12 thoracic, 5 lumbar), 9 are fused (5 sacral, 4 coccygeal).
How long is the average vertebral column?
72-75cm
What percentage of the length of the vertebral column is intervertebral discs?
25%
What can diurnal differences in height be due to compression of intervertebral discs throughout the day?
Up to 2cm
How does vertebra size change going down the vertebral column?
The vertebrae become larger as you move down the spine which helps facilitate load bearing and shock absorbance. This is also associated with thicker intervertebral discs in the lumbar spine.
What spinal structural feature allows for balanced bipedal movement?
The lumbar lordosis helps transfer upper body mass over the pelvis for balance.
What protection function does the vertebral column serve?
The vertebral column forms a canal through which the spinal cord and conus medullaris runs, providing protection to it.
How much rotation is possible at the lumbar vertebrae and why?
2-3 degrees as the vertical orientation of the facet joints prevents further rotation.
Which factors facilitate extension in the lumbar spine?
- Short spinous processes enable extension without collision of the processes.
- Larger intervertebral discs in the lumbar region.
What structure limits the extension of the lumbar spine?
Anterior longitudinal ligament
Which structures limit the flexion of the lumbar spine?
- Posterior longitudinal ligament
- Supraspinous ligament
When assessing posture, what are the key features to look out for?
- Clavicle and shoulder alignment
- Sternum and umbilicus alignment
- ASIS height on both sides
- Knee alignment
- Foot positioning
These should all be checked from the front, side and back views
What are the postural elements of sway back?
- Posterior tilt of the pelvis
- Thoracic kyphosis
Which muscles have increased activity in sway back posture?
Rectus abdominis
Which muscles have decreased activity in sway back posture?
- Internal abdominal obliques
- Iliopsoas
- Gluteus maximus
Which muscles are lengthened by sway back posture?
- Erector spinae
- Scapular stabilisers (serratus anterior, rhomboids and lower/mid trapezius)
- Lower abdominal muscles
- Hip flexors (iliopsoas, rectus femoris and tensor fascia latae)
Which muscles are shortened by sway back posture?
- Suboccipital muscle
- Sternocleidomastoid
- Scalenes
- Pectoralis muscles
- Lower part of erector spinae
- Upper abdominal muscles
- Gluteus maximus
- Hamstrings
What is kypholordotic posture?
This is where there is excessive cervical lordosis, thoracic kyphosis, lumbar lordosis and anterior pelvic tilt. It is effectively an exaggeration of normal curves of the spine.
Which muscles are lengthened with kypholordotic posture?
- Upper back muscles
- Front of the neck
- Abdominal muscles
- External abdominal obliques
- Hamstrings
Which muscles are shortened by kypholordotic posture?
- Quadriceps
- Iliopsoas
- Lower back
- Back of the neck
How does kypholordotic posure reduce lumar apophyseal joint space?
This posture causes a slackening of the posterior longitudinal ligament resulting in apophyseal facets not being maintained apart under as much tension.
What is flatback posture?
This is where the natural curves of the spine are lost, reducing the shock absorbing capacity of the spine, putting the spine at greater risk of damage.
Which muscles are lengthened in flatback posture?
- Quadriceps
- Lumbar erector spinae
Which muscles are shortened in flatback posture?
- Abdominal
- Hamstrings
What are the common elements of all vertebrae below C2?
- Large weight-bearing vertebral body anteriorly
- Vertebral arch made from two laminae and two pedicles
- A transverse process originating laterally from the point where laminae and pedicles meet
- A superior and an inferior facet originating from the point where the laminae and pedicles meet
- A spinous process originating posteriorly from where two laminae meet
Where are pedicles positioned in relation to vertebral bodies?
Pedicles pass from the superoposterolateral parts of the vertebral body and pass posteriorly to meet the anterolateral extremity of corresponding lamina.
What space is created between adjacent pedicles?
Intervertebral foramina through which spinal nerves and blood vessels can pass.
Where are the start and end points of the anterior longitudinal ligament?
Starts at the occipital bone.
Ends at the sacrum.
What doese the anterior longitudinal ligament attach to throughout its length?
- Upper and lower edge of each vertebral body by binding loosely to periosteum and strongly to the fibrocartilage of disc end plates
- Intervertebral discs by binding to hyaline cartilage
- Margins of the vertebrae
What are the functions of the anterior longitudinal ligament?
- Protect the anterior aspects of the intervertebral joints
- Limits excessive extension
What is the structure of the anterior longitudinal ligament?
It is split into 3 layers:
* Deep fibres span one segment between vertebrae.
* Intermediate fibres span 2-3 segments between vertebrae.
* Superficial fibres span 3-4 segments between vertebrae.
Which condition is thought to be associated with excessive stretch followed by rapid recoil of the anterior longitudinal ligament?
Whiplash
Which is stronger: Anterior or Posterior Longitudinal Ligament?
Anterior Longitudinal Ligament
What are the start and end points of the posterior longitudinal ligament?
Starts at the body of C2.
Ends at the posterior surface of the sacrum (S2).
What is the posterior longitudinal ligament a continuation of?
The cruciform ligament between C1 and C2.
How does posterior longitudinal ligament width change as it descends down the spine?
The width of the posterior longitudinal ligament is consistent throughout the cervical and thoracic spine but widens in the lumbar region.
What does the posterior longitudinal ligament bind to in the spine?
- Annulus fibrosis
- Cartilage of vertebral endplates
- Margins of the vertebral bodies
What are the functions of the posterior longitudinal ligament?
- To provide support to the weaker posterior of intervertebral discs
- To prevent excessive spinal flexion
What is the structure of the posterior longitudinal ligament?
It has two layers of fibres: superficial and deep. Deep span one vertebral segment whilst superficial span 3-4 vertebral segments.
How does the connective tissue content of ligamentum flavum vary compared to other spinal ligaments?
It is more elasticated due to a higher concentration of elastin.
What is the function of ligamentum flavum?
It provides a “brake” to laminar separation and its elasticity supports return to upright posture without buckling into the spinal canal.
Where is the ligamentum flavum?
Its medial fibres pass posteroinferiorly from one lamina to the next from C2 to S1. Its lateral fibres attach to the anterior part of the superior and inferior apophyseal facets, forming the anterior part of the joint capsule.
What causes the tension in ligamentum flavum in a neutral position?
Muscles in the lumbar spine apply tension on the thoracolumbar fascia which holds ligamentum flavum under tension.
Where does the supraspinous ligament run?
It connects the apices of spinous processes from C7 to L3/4
What is the structure of the supraspinous ligament?
It is consistently thick through the thoracic spine but widens in the lumbar region. It has deep fibres which span adjacent spinous processes, intermediate fibres which span 2-3 spinous processes and deep fibres which span 3-4 spinous processes.
Which muscle reinforces the deeper layers of the supraspinous ligament?
Multifidus
What is the function of the supraspinous ligament?
- Prevents excessive spinal flexion
- Helps to maintain upright posture
- Prevents excessive separation of spinous processes during flexion
What are interspinous ligaments?
These are thin, sheet-like ligaments which connect spinous processes from C1 to S1.
Which other ligaments do the interspinous ligaments interact with?
Anteriorly they merge with ligamentum flavum and posteriorly they merge with supraspinous ligaments.
What is the function of interspinous ligaments?
Prevents excessive flexion by restricting separation of spinous processes.
What are intertransverse ligaments?
Intertransverse ligaments are thin, sheet-like ligaments which connect adjacent transverse processes and prevent excessive lateral flexion.
What are the 3 vertebropelvic ligaments?
- Iliolumbar
- Sacrotuberous
- Sacrospinous
What is the structure of the iliolumbar ligament?
It is a double band of connective tissue. The anterior band is broad and flat, originating from the inferolateral aspect of the L5 transverse process, fanning out and inserting into the anterior portion of the iliac tuberosity.
The posterior band originates from the apex of the L5 transverse process and inserts onto the anterior margin and apex of the iliac crest.
What is the function of the iliolumbar ligament?
It stabilises the lumbosacral spine on the pelvis by restricting lumbosacral and sacroiliac joint movements.
What is the pubic symphysis?
This is a fibrocartilaginous disc which forms the joint between the articulating surfaces of the pubic bones.
What is the function of the pubic symphysis?
It resists shearing and compressive forces and allows small amounts of movement, producing greater shock absorption.
What is the structure of the articular surfaces of the pubic bones?
The articulating surfaces of each pubic bone is ovular and slightly convex, coated in 1-3mm of hyaline cartilage.
Which ligaments reinforce the pubic symphysis?
- Superior pubic ligament
- Inferior pubic ligament
- Anterior pubic ligament
- Posterior pubic ligament
Where is the superior pubic ligament located?
It sits over the superior aspect of the pubic symphysis and attaches to the pubic crests as far laterally as the pubic tubercles.
What is the location of the inferior public ligament?
It forms an arch, spanning the inferior aspect of the pubic symphysis and providse fibres which blend with the disc itself.
What are the attachments of the anterior pubic ligament?
It attaches the two pubic rami anteriorly and binds the periosteum laterally.
What is the structure of the posterior pubic ligament?
It is made of a few thin fibres.
What are the origins of multifidus?
- Dorsal surface of the iliac spine
- Dorsal surface of the sacrum
- Mammilary processes of lumbar vertebrae
- Transverse processes of thoracic vertebrae
- Articulating processes of C4-C7
What are the insertions of multifidus?
Spinous processes of lumbar, thoracic and cervical vertebrae, 2-5 vertebrae above the origin.
Which actions are facilitated by multifidus?
- Trunk and neck extension
- Lumbar spine support
Which nerves supply mulitifidus?
Medial branches of posterior rami of cervical, thoracic and lumbar nerves.
Which blood vessels supply mulitifidus?
- Occipital artery
- Deep cervical artery
- Vertebral artery
- Posterior intercostal artery
- Lumbar artery
- Lateral sacral arteries
Which structures are deep to multifidus?
Rotatores muscles
Which structure are superficial to multifidus?
Erector spinae
Which structures are located laterally to multifidus?
Levatorus costarum muscles
Which structures are located medially to multifidus?
Interspinalis muscles
Which exercises can strengthen multifidus?
- Bird dog
- Superman
- Side plank
Which exercises can be used to stretch multifidus?
- Cat cow
- Bird dog
How do you palpate multifidus?
- Place your patient in prone lying
- Palpate the laminar groove (space between spinous and transverse processes) and you will mainly feel erector spinae
- Move slightly laterally, palpate deeply and then push inwards to feel multifidus.
Alternatively you can palpate the posterior surface of the sacrum and ask the patient to extend their trunk and neck and you can feel the origins of multifidus.
What type of muscle is multifidus?
Parallel, non-fusiform
What is the most common cause of multifidus injury?
Lifting heavy objects far away from the body e.g., a car battery
What did Shahidi et al 2017 discover about multifidus?
They found that in individuals with chronic, degenerative lumbar spine pathologies there was an increase in inflammatory markers and reduction in vascularisation in their multifidus muscles.
What are the origins of rectus abdominis?
- Pubic crest
- Pubic symphysis
What are the insertions of rectus abdominis?
- Xiphoid process
- Costal cartilages of ribs 5-7
What functions are mediated by rectus abdominis?
- Trunk flexion
- Compresses and provides support to adjacent abdominal structures
Which nerves supply rectus abdominis?
The anterior rami of 6th-12th thoracic nerves
Which blood vessels supply rectus abdominis?
- Superior epigastric artery
- Inferior epigastric artery
Which structures are located anteriorly to rectus abdominis?
Pyramidalis
Which structures are located laterally to rectus abdominis?
- External abdominal obliques
- Internal abdominal obliques
- Transversus abdominis
Which structure is medial to rectus abdominis?
Linea alba
Which exercises can be used to strengthen rectus abdominis?
- Sit-ups
- Crunches
- Flutter kicks
- Leg raises
Which exercises can be used to stretch rectus abdominis?
- Cat cow
- Updog
How do you palpate rectus abdominis?
- Place the patient in supine and palpate from the xiphoid process to the pubis with the patient relaxed
- Ask the patient to raise their head, neck and shoulders off the plinth and you will be able to feel activation of rectus abdominis
What type of muscle is rectus abdominis?
Parallel, fusiform muscle
What are the origins of pyramidalis?
- Body of pubic
- Anterior pubic ligament
What is the insertion of pyramidalis?
Linea alba
What function is mediated by pyramidalis?
Tensing of linea alba
Which nerves supply pyramidalis?
- Anterior ramus of 12th thoracic nerve
- Iliohypogastric nerve
- Ilioinguinal nerve
Which blood vessel supplies pyramidalis?
Inferior epigastric artery
Which structures are deep to pyramidalis?
Rectus abdominis
Which structures are superficial to pyramidalis?
The anterior layer of the rectus sheath
What type of muscle is pyramidalis?
Convergent
What are the origins of the internal abdominal obliques?
- Thoracolumbar fascia
- Iliac crest
- Inguinal ligament
What are the insertions of the internal abdominal obliques?
- Inferior margins of 10th-12th ribs and adjacent costal cartilages
- Linea alba
- Pecten pubis
Which actions are mediated by internal abdominal obliques?
- Trunk flexion
- Trunk lateral flexion
- Trunk rotation
- Compresses and provides support for adjacent abdominal structures
Which nerves supply the internal abdominal obliques?
- Anterior rami of 7th-12th thoracic nerves
- Ilioinguinal nerve
- Iliohypogastric nerve
Which blood vessels supply the internal abdominal obliques?
- Lower posterior intercostal artery
- Subcostal artery
- Deep circumflex iliac artery
- Superior epigastric artery
- Inferior epigastric artery
Which structures are deep to internal abdominal obliques?
Transversus abdominis
Which structures are superficial to internal abdominal obliques?
External abdominal obliques
Which structures are medial to internal abdominal obliques?
Rectus abdominis
Which exercises can be used to strengthen internal abdominal obliques?
- Side plank
- Weighted trunk rotation
- Russian twists
- Crunches with twist
How can you stretch internal abdominal obliques?
- Standing side bend
- Updog
- Both knees to 90 degrees in supine and allow hips to drop outwards
How do you palpate internal abdominal obliques?
- Place the patient in supine
- Palpate just below 10th-12th ribs
- Request the patient to lift their opposite shoulder towards the side you are palpating and you will feel clear activation of internal abdominal obliques.
Which structures do internal abdominal obliques contribute towards?
Internal abdominal obliques give rise to a broad aponeurosis which forms part of the rectus sheath, inguinal canal and Petit’s triangle.
What type of muscle are the internal abdominal obliques?
Parallel, non fusiform
What are the origins of the external abdominal obliques?
- External surface and inferior border of 5th-12th ribs
What are the insertions of the external abdominal obliques?
- ASIS
- Anterior half of iliac crest
- Pubic crest
- Pubic tubercle
- Linea alba
Which actions are mediated by external abdominal obliques?
- Trunk flexion
- Trunk lateral flexion
- Trunk rotation
- Compresses and supports surrounding abdominal structures
Which nerves innervate external abdominal obliques?
Anterior rami of 7th-12th ribs
Which blood vessels supply the external abdominal obliques?
- Lower posterior intercostal artery
- Subcostal artery
- Deep circumflex iliac artery
- Superior epigastric artery
- Inferior epigastric artery
Which structures are deep to external abdominal obliques?
- External intercostal muscles
- Internal abdominal obliques
- Transversus abdominis
Which structures are medial to external abdominal obliques?
Rectus abdominis
Which exercises can be used to strengthen external abdominal obliques?
- Side plank
- Weighted trunk rotation
- Russian twists
- Crunches with twist
How can you stretch external abdominal obliques?
- Standing side bend
- Updog
- Supine hip fallout
How do you palpate external abdominal obliques?
- Ask the patient to lie in supine
- Palpate along the lower ribs (5-12)
- Ask the patient to raise their shoulder on the side you are palpating and to bring it towards the opposite hip
You will clearly feel external abdominal obliques firing in this case
Which structure is formed from a broad aponeurosis of external abdominal obliques?
The inguinal ligament
Which muscles do external abdominal obliques interdigitate with near its origins?
- Serratus anterior
- Latissimus dorsi
What type of muscle are external abdominal obliques?
Parallel, non-fusiform
What are the origins of psoas minor?
- Vertebral bodies of T12-L1 (anterolateral aspect)
- T12-L1 intervertebral disc
What are the insertions of psoas minor?
- Iliopectineal eminence
- Pecten pubis
Which actions are mediated by psoas minor?
Trunk flexion
Which nerves innervate psoas minor?
Anterior ramus of 1st lumbar nerve
Which blood vessels supply psoas minor?
Lumbar arteries
Which structure are deep to psoas minor?
Psoas major
Which structures are superficial to psoas minor?
Ureter
Which structures are lateral to psoas minor?
Kidneys
Which structures are medial to psoas minor?
Lumbar vertebrae
Which movement is a good test of psoas strength?
Standing on one leg, lifting one knee as high as possible towards your chest and standing for 30 seconds
Which exercises can be used to strengthen psoas minor?
- Lunges
- Supine leg raises
- Tabletop opposite elbow to knee crunches
- Standing hip flexion
Which movements can be used to stretch psoas minor?
Anything that creates a posterior pelvic tilt e.g., posterior pelvic tilts, glute bridge with posterior pelvic tilt etc
How do you palpate psoas minor?
You don’t. It is beneath external abdominal oblique, internal abdominal oblique, transversus abdominis, the inguinal ligament and the digestive organs and so cannot be reached.
What percentage of people have a psoas minor muscle?
40%
What type of muscle is psoas minor?
Thin fusiform