orthopedic pathology (spinal pathologies) Flashcards
1
Q
scoliosis
A
Abnormal lateral curvature of the spine
On x-ray, spine may look more like an “S” or a “C” than a straight line
2
Q
left vs right scoliosis
(levoscoliosis vs dextroscoliosis)
A
Named according to convexity
Left more common in L-spine
Right more common in T-spine
3
Q
May also involve rotational component
A
esp in thoracic spine (“RIB HUMP”)
SPs face toward concave side (thoracic)
4
Q
terms related to classification
A
Right thoracic scoiosis
left lumbar scoliosis
right THORACO-LUMBAR scoliosis (both)
right thoracic - left lumbar scoliosis
5
Q
classifiction via etiology
A
Idiopathic scoliosis (80%)
–> MOST COMMON
osteopathic scoliosis
–> Due to bone abnormality (STRUCTURAL SCOLIOSIS)
myopathic scoliosis
–> Due to muscle weakness (could be FUNCTIONAL SCOLIOSIS ??)
Neurologic/Neuropathic SCOLIOSIS
6
Q
classificaiton according to age of onset
A
Congenital
Infantile
Juvenile
Adolescent
Adult
7
Q
Structural scoliosis
A
Fixed curvature of the spine associated with vertebral rotation and asymmetry of the ligaments
Can be caused by congenital, neuromuscular, musculoskeletal, idiopathic
ALSO, vertebral deformities / malformation (???)
8
Q
note vertebral malformation vs structural scoliosis
A
PARTIAL UNILATERAL FAILURE OF FORMATION (WEDGE)
COMPLETE UNILATERAL FAILURE OF FORMATION (HEMIVERTEBRA)
UNILATERAL FAILURE OF SEGMENTATION (CONGENITAL BAR)
BILATERAL FAILURE OF SEGMENTATION (BLOCK VERTEBRA)
9
Q
what percentage children need intervention? (SURGICAL???)
A
2.5 %
1/10 Children diagnosed ——> 25% of those require intervention
—-> Rest sorts itself out on its own (???)
10
Q
what conditions increase incidence of Scoliosis in children?
A
Incidence increases with cerebral palsy, spina bifida, neurofibromatosis, muscular dystrophy
11
Q
male vs female difference?
A
Equal in males and females but females are more likely to develop severe curvatures that require intervention
12
Q
Idiopathic adolescent scoliosis
A
Idiopathic
Seems to have a genetic component – Recurrence among relatives
13
Q
WHY???? (Idiopathic adolescent scoliossi)
A
Common theory is that sensory information is either misinterpreted or incorrect resulting in inappropriate output regarding body orientation.
——-> SAME THEORY AS CHARCOT’S NEUROPATHY
14
Q
WHY NOT (idiopathic adolescent scoliosis)
A
REACTION NOT A CAUSE
Muscular imbalances in activity or strength do not seem to be a cause. Evidence suggests that these imbalances are reactions to the curve rather than a cause.
15
Q
Idiopathic adolescent Scoliosis, female vs male
A
GENETIC COMPONENT
FEMALES
Most common form is adolescent idiopathic scoliosis,
has a genetic component and is more common in females
16
Q
Cobb Angle Test
A
The Cobb angle is the most widely used measurement to quantify the magnitude of spinal deformities, especially scoliosis, on plain radiographs.
Scoliosis is a lateral spinal curvature with a Cobb angle of >10° 4.
The Cobb angle technique can also assess the degree of kyphosis or lordosis in the sagittal plane 7.
17
Q
Idiopathic adolescecnt scoliosis vs COBB ANGLE
A
Prevalence of AIS is approx 2-3% with less than 10% on screening evaluation requiring treatment (based on 10 degree cobb angle)
18
Q
symptoms/presentation
A
Asymptomatic
Pain
Uneven musculature
A rib “hump” and/or a prominent shoulder blade
Uneven hip, rib cage, and shoulder levels
Asymmetric size or location of breast
Uneven distance between arm and body
19
Q
Diagnosis
A
Presentation
Adam’s (forward bend) test
Scoliometer measurements (measures rib hump)
X-ray
20
Q
Forward bend test
A
NOTE THAT SOME PATIENTS CANNOT CURVE THEIR BACK (BEND FORWARD WITH FLAT BACK)
—-> shortened spinal cord = prevents back curving to create shortest distance in vertebral canal for (congenitally?) shorter spinal cord
21
Q
APEX scoliosis
A
most protruding vertebra
22
Q
Prognosis Scoliosis
A
Depends on likelihood of progression
Generally larger curves carry a higher risk of progression than smaller curves
Thoracic curves carry a higher risk of progression than lumbar or thoracolumbar curves
Patients who have not reached skeletal maturity have a higher likelihood of progression.
—–> Risser’s Sign
—–> Onset before (first menstruation) menarche
Males with similar sized curves have less likelihood of progression
23
Q
WHICH CURVE HAS GREATER RISK OF PROGRESSION
A
THORACIC CURVE*****
24
Q
Risser’s sign
A
The Risser sign is an indirect measure of skeletal maturity, whereby the degree of ossification of the iliac apophysis by x-ray evaluation is used to judge overall skeletal development.
I.e.
Growth plate not closed = less mature skeleton = more likelihood of scoliosis progressing/worsening
(Starting earlier = worse)
25
which gender likelihood of progression
females
26
Management/treatment
Observation
Bracing
Surgery
Management is complex and is determined by the severity of the curvature and degree of skeletal maturity, which together help predict the likelihood of progression
27
surgery scoliosis
insert plates/screws
incision/open every once a in a while to tighten screws to continue manipulating direction of spine
----> similar concept to dental braces
28
Fucntional scoliosis
Have no permanent rotary component
not related to structure ---> more likely to be fixable/treatable
Correct themselves on positional changes
Compensation for biomechanical problems or due to a muscle spasm
E.g. pain, poor posture, leg length discrepancy, disc herniation, etc
Disappear if the cause is remedied
29
strucutral vs functional scoliosis
Positional change (adams test, bend towards convexity)
Pain (especially with forward bending)
Idiopathic Adolescent Scoliosis is usually asymptomatic until later in life
30
BENDING TOWARD CONVEXITY
If bending toward convexity, curve persist ==> STRUCTURAL SCOLIOSIS
IF BENDING TOWARD convexity, curve temporarily disappears or is reduced, could be FUNCTIONAL SCOLIOSIS
---> Not as result of malformation of vertebral structures
31
Cervical spine
**
32
Whiplash
Acceleration-deceleration injury to head and neck relative to body
Cervical flexion-extension sprain/strain injury
Trauma esp. MVA esp. rear-impact collisions
Contributing factors – active TrPs in SCMs; other concurrent health conditions
33
MOI (FYI)
Vehicle is struck from behind
Seat pushes torso as vehicle moves forward
Head is fixed
Torso moves upward
***
Vehicle and torso reach peak forward acceleration
Seat recoils to original position
Head and neck stay in place
Anterior neck mm and ligaments overstretched
***
Head and neck at peak forward acceleration
Vehicle and torso slowing down
***
Head and torso at full deceleration
Shoulder harness restrains torso
Head and neck continue to flex forward
Head moves into hyperflexion
Most stress places on lower C-spine and upper T-spine
34
Other factors to consider (whiplash) ----> (TO ASK PATIENTS)
--> gives more context/info to potential questions like which structures affected
Head position
Seatbelts
Headrest position
Seat position
Stature
Airbags
Front or side impact
35
tissues involved
Cervical-spine, Thoracic-spine, head
Vertebrae
DISKS
Facet joints
Joint capsules/ligaments
TMJ
ALL, PLL (ANTEIROR/posterior longitudinal lig)
36
other tissue involved
Lymphatics
Fascia
Blood vessels
Nerve roots
Cranial nerves
ANS
Spinal cord
37
muscles involved
suboccipitals
rotatores, multifidi, semispinalis cervicis, longissimus cervicis
upper trapezius, levator scapulae
***
rectus capitis anterior, longus capitis, longus colli
SCM, platysma
mylohyoid, omohyoid, suprahyoid, infrahyoid
***
rectus capitis lateralis
anterior, middle, posterior scalene
***
Muscles of mastication
CAN BE AFFECTED
THORAX --> intercostals, posterior spinal muscles, diaphragm
38
which two groups of muscles also can be affected (whiplash) ??
Muscles of mastication
CAN BE AFFECTED
THORAX --> intercostals, posterior spinal muscles, diaphragm
39
FOUR GRADES OF WHIPLASH DECRI)BED BY
Four grades of Whiplash-Associated Disorder were defined by the Quebec Task Force on Whiplash-associated disorders (WADs):
40
FOUR GRADES
Grade 0: no neck pain, stiffness, or any physical signs are noticed
Grade 1: neck complaints of pain, stiffness or tenderness only but no physical signs are noted by the examining physician.
---> E.g.
no loss of ROM, or tenderness upon palpation
Grade 2: neck complaints and the examining physician finds decreased range of motion and point tenderness in the neck.
Grade 3: neck complaints plus neurological signs such as decreased deep tendon reflexes, weakness and sensory deficits.
---> NEUROLOGICAL Sx
Grade 4: neck complaints and fracture or dislocation, or injury to the spinal cord.
---> Fx, dislocation, spinal cord injury
41
Clinical manifestiation (acute)
Spasm
Strain
Contracture
Facet joint irritation
Fracture
Nerve tractioning
42
other acute clinical manifestation
Loss of consciousness
Headache
Edema
Tenderness
Deafness, dizziness, dysphagia, memory loss, nausea, TMJ pain, TOS, tinnitus,
Decreased strength
43
IMPORTANT FEATURES TO NOTE
ear-related symptoms:
tinniitus
deafness
dizziness
(ear proprioceptors)
ALSO:
Nausea
(Vestibular system = ear)
44
Chronic clinical manifestations
Pain
Headache
Contracture
Spasms
TMJ dysfunction
Trigger points
**
Reduced ROM
Adhesions
Hypermobility
Decreased strength
Atrophy
DDD or DJD
45
Treatment
Chiropractic, physiotherapy, massage
Stretching/strengthening
Hydrotherapy
Mobilization
Traction
Meds
Surgery
46
Torticollis
twisted
neck
47
what is "
Abnormal positioning of head and neck relative to body (wry neck)
48
typical presentaiton
Lateral flexion towards the affected side
Rotation away from affect side
Shoulder on affected side is raised
Neck may be in flexion or extension
49
Lateral flexion towards the affected side
Rotation away from affect side
SCM
50
Acute acquired torticollis
Painful unilateral shortening or spasm of neck muscles resulting in an abnormal head position
Any age
51
Causes "
Activation of latent trigger points
Ispilateral SCMs, scalenes, levator scapula
Subluxation of C1-C2 due to trauma
Facet joint irritation
Infection or inflammation
Disc pain due to DJD
52
Clinical manifestations
Usually sudden onset
Typical position
Affected muscles are shortened and in spasm
Pain especially with movement
53
Clinical manifestations
Tinnitus
Nausea
(ear-related symptoms)
Lacrimation (pressure on Lacrimal glands
Referred pain
54
Torticollis treatment
Medication (analgesics, m. relaxants)
Chiropractic, physiotherapy, massage
Hydrotherapy
Breathing exercises
Stretching, strengthening (PT)
Time (self-limiting condition)
55
SPASMODIC TORTICOLLIS (aka CERVICAL DYSTONIA)
Localized dystonia resulting in an involuntary spasm of cervical muscles and abnormal head position
Worse under stress
56
dystonia
a state of abnormal muscle tone resulting in muscular spasm and abnormal posture, typically due to neurological disease or a side effect of drug therapy.
57
Etiology (Cervical dystonia)
Idiopathic
CNS lesions (SPASMS??)
Malformation at C0-C1
Postural dysfunction
Trauma
Iatrogenic (anti-psychotic/anti-nausea tx/med ??)
58
Contributing factors
Depression
Stress
Social/personal upheavals
Occupational positioning of head
59
Clinical manifestations
Adult onset
Typical torticollis position
Affected muscles in neck twitch and jerk
Affected shoulder shrugs
Twitching may spread to facial and arm muscles (CNS LESIONS?????)
60
other clinical manifestation
Intermittent or permanent or spontaneous remittance or increasing severity
Intensity varies according to head position
Exacerbated by social stress/head position
Improved by certain positions
61
Tx (Spasmodic torticollis, Cervical dystonia)
Antispasmodic meds
Botox
Biofeedback
Agonist contraction, relaxation
Postural retraining
Passive stretching
Relaxation courses
Breathing exercise
AROM exercises
62
Congenital torticollis
A contracturing of one SCM muscle resulting in an abnormal head position
Present from infancy
63
etiology (congenital torticollis)
Idiopathic
Theories
Trauma in birth process causing inflammation and fibrosing of SCM
Malposition of fetus in utero
Torsion of fetal cranial bones
64
Clinical manifestation (congenital torticollis)
Present from infancy
Typical torticollis positioning
Contracture, thickening and shortening of one SCM muscle, scalenes, associated fascia
Palpable mass in muscle
Postural dysfunction
65
late clinical manifestations
Compression on cranial nerves and vasculature
TMJ dysfunction on affected side
DDD (C-spine)
OA (C-spine)
66
TMJ?
TMJ and related disorders of the jaw system can put pressure on nerves in the jaw, and it can lead to the inefficient working of the jaw muscles or overexertion, both of which increase demands on the neck muscles. As a result, TMJ might have a role in causing torticollis.
67
Tx (congenital torticollis)
Massage (neuromuscular therapy)
Physiotherapy
Stretching/strengthening
ROM exercises
Craniosacral
Surgery
68
Cervical rib
Separate piece of bone that articulates with the transverse process of one or more cervical vertebrae
Most common at C7, C6, C5
0.5% - prevalence
Females>males (2:1)
Bilateral (66%)
69
cervical rib ...
Often asymptomatic until middle age when shoulders begins to droop
May result in neurovascular compression (TOS)
---> Subclavian vessels (artery/vein)
---> Brachial plexus
70
TMJ dysfunction
Disorder of the muscles of mastication, the temporomandibular joints, and associated structures
Most common age of onset 20 - 50
Women>men (5:1)
71
Causes TMJD
Imbalances in muscles of mastication
Muscle overuse
Cranial bone/C-spine misalignment
Postural dysfunction
Stress/trauma
Joint pathology
Sinus blockage/infection
72
muscles of throat/nasal cavity TMJD
TMJ disorder can cause nasal discharge. The muscles responsible for chewing and jaw movement are connected to the muscles in the throat and nasal cavities.
When these muscles become tight or inflamed due to TMJ disorder, they can cause a sensation of congestion.
73
contributing/risk factors (TMJD)
Genetic predisposition
Trauma to neck, face, jaw
Tissue alteration
Stress/grinding/clenching
Teeth crowding/misalignment
Missing teeth
Playing musical instruments
chewing/smoking
74
clinical presentation (TMJD)
Unilateral or bilateral
Pain
Clicking, popping with jaw movement
Headache
Spasm/hypertonicity/trigger points – temporalis, masseter, medial pterygoid, lateral pterygoid, digastric, mylohyloid, genoihyoid, infrahyoid, C-spine
75
clinical presentation (TMJD) 2
Decreased ROM
Catching/locking
Ear dysfunction
Inflammation, edema, swelling
Tinnitus
Lacrimation
Paresthesia
Contracture/DJD (late)
76
ear related sx (TMJD)
Ear dysfunction
Tinnitus
77
TMJD lacrimation
When TMJ syndrome causes tension in the muscles and surrounding tissues, it can sometimes effect this nerve resulting in blurred vision, watery eyes and light sensitivity.
78
Management TMJD
Diagnosis
Dentist, chiropractor, MD
History, Physical exam, imaging
79
tx TMJD
Massage, chiropractic, physiotherapy, exercises, mobilization, dental splints, meds, surgery, stress management, modification of ADLs
80
Scheuermann's Disease
Most common cause of structural kyphosis in adolescents
81
Scheuermann's etiology
Etiology is idiopathic, but probably multifactorial
82
Scheuermann's when
Usually begins in puberty (age 13 – 16)
83
Scheuermann's gender
mostly males
84
Scheuermann's how common?
Uncommon (less than 1%)
85
osteochondrosis
Osteochondrosis is a self-limiting developmental derangement of normal bone growth, primarily involving the centers of ossification in the epiphysis.
It usually begins in childhood as a degenerative or necrotic condition.
By definition, osteochondrosis is an aseptic ischemic necrosis.
86
osteochondrosis define 2
Osteochondrosis is the descriptive term given to a group of disorders affecting an ossification centre in a child or adolescent resulting in alteration of endochondral ossification.
a disease especially of children and young animals in which an ossification center especially in the epiphyses of long bones undergoes degeneration followed by calcification
87
what were examples of osteochondrosis we saw?
Legg-Calvé-Perthes disease
Sever disease
88
Scheuermann's & osteochondrosis
Considered part of a larger group of diseases called osteochondrosis
89
Scheuermann's pathogenesis
Growth ossification centres stop receiving adequate blood supply, leading to degeneration and necrosis
Blood supply is regrown and bone continues to grow, but not without structural deformity
90
Scheuermann's often seen @
Lower thoracic or upper lumbar vertebrae affected first
91
Scheuermann's -- what type of structural deformity?
How is the structural deformity quantified?
Structural deformity characterized by anterior wedging of five degrees or more of three adjacent thoracic bodies
92
Scheuermann's features
Affected children are tall with advanced skeletal maturity and poor posture
thoracic Hyperkyphosis
93
note gender of 3 osteochondroses we learned
Legg-Calve Perthes
Sever's
Scheuermann's
boys > girls
94
Scheuermann's -- how about lateral deformity?
Possible scoliosis
95
Scheuermann's -- pain or no?
May be painful or asymptomatic
Course is mild but long (years)
96
Scheuermann's treatment
Treatment – rest, bracing, surgery (plates/screws), physical therapy, meds
97
Sprengel's deformity
Congenital malposition of the scapula
Scapula begin near the c-spine and descend during development
With Sprengel’s deformity, the scapula fails to descend
98
What diseases associated with Sprengel's deformity
Spina bifida
Klippel-Feil syndrome
Hemivertibrae (scoliosis)
99
Omovertebral bone
The omovertebral bone (os omovertebrale) is present in ~35% (range 19-47%) of cases of Sprengel deformity.
Bone extending off of one side of bifid SP of a cervical vertebra
connect to scapula (??)
"Omo" = shoulder/scapula
100
Sprengel's deformity most common in which gender
Girls > boys (3:1)
101
Sprengel's deformity treatment
Treated with physical therapy and possibly surgery
102
Pectus excavatum
Most common deformity of chest wall
Aka funnel chest
Midline depression of sternum
103
Pectus carinatum
Anterior protrusion of sternum
Prominent sternum
Aka pigeon breast
104
carinatum
From the Latin carina, meaning keel
105
Barrel chest
Barrel chest – increase in the antero-posterior dimensions of the chest wall; most commonly associated with emphysema
106
emphysema define
Emphysema is a lung condition that causes shortness of breath.
In people with emphysema, the air sacs in the lungs (alveoli) are damaged.
Over time, the inner walls of the air sacs weaken and rupture — creating larger air spaces instead of many small ones.
107
Central Stenosis
Note "Mass effect"
Narrowing of the spinal canal
108
Central stenosis primary vs secondary
Can be primary (congenital)
Can be secondary due to DJD (m/c),
subluxation,
edema,
disc herniation/DDD,
tumour,
osteoporosis, etc.
109
osteoporosis and central stenosis
compression fractures (?)
"Osteoporosis predisposes patients to fracture, progressive spinal deformities, and stenosis"
110
where is central stenosis most common
May affect any portion of the spine, but is most common in the lumbar spine
111
Stenosis and neurological signs/symptoms
Stenosis can lead to neurological symptoms including:
Numbness, tingling and weakness to the lower extremities
Bowel and bladder changes, such as incontinence
112
central stenosis and paralysis
in severe cases, paralysis can occur due to spinal cord damage
113
Spondylosis, Spondylitis, Spondylolysis, Spondylolisthesis
Spondulos = vertebra
osis = condition/pathological state
itis = inflammation
lysis = degeneration/disintegration
listhesis = slipping/sliding
114
Pars interarticularis
"The pars interarticularis, or pars for short, is the part of a vertebra located between the inferior and superior articular processes of the facet joint."
115
Pars interarticularis etymology
"The pars interarticularis means the 'part between the articulations' in Latin and is the bony bridge that joins these two upper and lower facets."
116
Spondylitis define
Note "Ankylosing Spondylitis"
"inflammation of the joints of the backbone."
117
Ankylosis/Ankylose etymology
"(of bones or a joint) be or become stiffened or united by ankylosis."
"From Ancient Greek ἀγκύλωσις (ankúlōsis, “a stiffening of the joints”), from ἀγκυλόειν (ankulóein, “to crook, bend”), from ἀγκύλος (ankúlos, “bent, crooked”)."
118
Spondylosis define
"a painful condition of the spine resulting from the degeneration of the intervertebral disks."
"Most often, the term spondylosis is used to describe osteoarthritis of the spine, but it is also commonly used to describe any manner of spinal degeneration."
"Neck or back pain that develops as we age may be a sign of spondylosis, a degenerative condition that affects the spine. Spondylosis is a normal, age-related condition."
119
Spondylolysis define
1
"Spondylolysis is a fracture (crack or break) in a vertebra (bone in the spine). It can happen from repetitive stress or injuries to the spine."
2
"Spondylolysis is a stress fracture through the pars interarticularis of the lumbar vertebrae."
3
"“Spondylolysis” is the medical term for a small crack (fracture) between two vertebrae in your spine."
120
spondylolisthesis define
Spondylolisthesis is a displacement of a vertebra in which the bone slides out of its proper position onto the bone below it.
Most often, this displacement occurs following a break or fracture.
Surgery may be necessary to correct the condition if too much movement occurs and the bones begin to press on nerves.
In severe cases that are not treated, paralysis can occur
121
note description of spondylosis on class notes
Broad term describing vertebral column degeneration
Most commonly used to refer to vertebral osteoarthritis
122
Spondylolysis (class notes)
“Pars defect”
Interruption/malformation of the pars interarticularis
Can be unilateral or bilateral
Can be asymptomatic
May lead to spondylolisthesis
123
Where is Spondylolysis most common?
Most often occurs at L5-S1
124
Spondylolisthesis class notes
The gap at the pars defect widens
May be asymptomatic
May cause back pain
125
which postural defect can occur in Spondylolisthesis
May cause hyperlordosis
126
where is spondylolisthesis MOST COMMON
Can occur at any spinal level, but most commonly at L5-S1
127
which shift direction is most common in spondylolisthesis
The shift can occur in any direction, but most commonly anterior/posterior shift
--> Anterolisthesis
--> Posterolisthesis
128
spondylolisthesis, neurological symptoms and treatment
May cause neurological symptoms
---> severe untreated cases can lead to paralysis
"Treatment depends on clinical presentation and degree of instability"
129
Schmorl's nodes
Projection of the intervertebral disc into the vertebral body end plate ("Physeal plate" ??)
digs into bone (??)
Associated with conditions such as Scheuermann’s disease
Heritable link (etiology)
130
Physis
ancient Greek term for "nature", from the verbal noun φύσις, "phusis", meaning "growing", "becoming", itself from φύω, "to grow", "to appear".
EPI-physis
META-physis
Meta =
meta- 6. a prefix appearing in loanwords from Greek, with the meanings “after,” “along with,” “beyond,” “among,” “behind,”
131
Scheuermann's disease -- Schmorl's nodes
With Scheuermann's disease, there are sometimes additional abnormalities of the affected vertebrae. These abnormalities are called "Schmorl's nodes".
These nodes are areas where the disc (cushion) between each vertebra pushes through the bone at the bottom and the top of the vertebra.
132
Schmorl's nodes -- why?
and why with Scheuermann's?
Researchers believe that the weakening of the vertebral endplates causes Schmorl's nodes.
However, these nodes may also have links to other conditions, such as: Scheuermann's disease, which causes the vertebra to grow unevenly during childhood. metabolic diseases.
133
Butterfly vertebrae
Non-union of the two halves of the vertebral body
Extremely rare
Associated with some congenital diseases not seen in this course
134
Degenerative Disc Disease (DDD)
Degenerative joint changes at the intervertebral disc
Common musculoskeletal condition
135
intervertebral disc
Functions as a shock absorber and to allow movement between vertebrae
136
what does ddd do to discs -- how does it affect discs
Degeneration causes alterations in volume, shape, structure and composition
These will decrease motion and alter mechanical properties of the spine
137
two components of discs
Annulus fibrosus
annulus = ring
Concentric layers of collagen
Posterior side is thinner and less firmly attached to endplates
138
which side is thinner and elss firmly attached to vertebral body (endplate)
(more mobile?)
Posterior side is thinner and less firmly attached to endplates (MORE MOBILE)
RECALL medial meniscus --> posteiror side is LESS mobile (MOST COMMONLY INJURED)
139
two components of discs
Nucleus pulposus
Jelly-like material in the center of the disc
Has a high-water content and is quite viscous
Moves slightly with movement of spine
140
2
Annulus fibrosus
Nucleus pulposus
141
how is separation of vertebrae determined
Internal pressure of disc maintains:
Separation of vertebrae
142
discs, innervation
Only posterior peripheral aspect of annulus fibrosus is innervated
143
discs, blood supply
Discs are hypovascular
Slow repair process
Only periphery is vascularized
144
how does rest of disc received O2/nutrients
Rest of disc receives nutrition by diffusion through vertebral endplates
145
disc changes with age
Considered a “normal” degenerative process (wear and tear)
1) Fibrous changes within nucleus
2) Changes in organization of annulus fibrosus
3) Disappearance of the cartilaginous endplates
146
what happens to nucleus pulposus
AT WHAT AGE?
Number of cells and the concentration of proteoglycans and water decreases
Gradually nucleus changes to a fibrous material similar to the annular fibers
Typically occurs around 40-50 years of age
147
proteoglycan
a compound consisting of a protein bonded to glycosaminoglycan groups, present especially in connective tissue.
148
what is the result of fibrosis of nucleus pulposus
Results in decreased disc height and reduced range of motion
149
what happens to annular fibers with age?
Annular fibers become weaker and less elastic
Fibers compress and bulge
Creates tension in outer layers
150
what can weakened fibrous layers (annulus fibrosus) lead to
Clefts appear between annular layers and progress to gaps and larger tears
This can allow nucleus to protrude (DISC HERNIATION)
151
which side of disc weaker?
Posterolateral portion of disc weakens first
affecting which movements?
---> Flexion and rotational movements
152
what happens at edges of vertebral bodies?
Altered disc mechanics encourages bone formation at edges of vertebrae
Osteophytes (exostosis)
153
what can compression of vertebral discs do to nerve roots?
compression = pain, numbness/tingling, and other neurological symptoms
154
DDD risk factors
Genetics
Age
Weight
Atherosclerosis
Repetitive mechanical loading
Trauma
Muscle imbalances
155
atherosclerosis and DDD (?)
poor blood supply = poor regeneration/nutrition of discs, which already have limited blood supply
156
which ages is herniation most common?
Most common at 30 – 45 years of age
Annular fibers are weakened and disc is still hydrated
157
which ages is herniation less common?
Rupture is less likely after age 50
Disc is usually fibrosed
158
where do majority of disc herniations occur
98% of lumbar herniations occur at L4-L5 and L5-S1 levels.
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what is herniation?
which direction most common?
which movement most common MOI?
Herniation is commonly used to describe a disc injury that results from a rupture of annular fibers
Disc most commonly bulges posterolaterally and may compress nerve roots and ligaments that are pain sensitive
Suggested mechanism of injury is flexion and rotational/torsional forces
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disc herniation and mass effect
may compress nerve roots and ligaments that are pain sensitive
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Disc herniation, single event, or repetitive use (?)
May be a single traumatic event, repeated minor strains or sustained flexion
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4 stages of disc herniation
1) degeneration
---> annulus fibrosus is degerating; minor displacement may be seen (?)
2) prolapse
---> annulus fibrosus is displaced; no break/protrusion of nucleus pulposus
3) extrusion
---> nucleus pulposus protruding from annulus fibrosus (displacement & break)
4) sequestration
---> protruding as well as fragmenting / "dripping"
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DDD SSx 1
Many cases are asymptomatic
Imaging does not always correlate with symptoms
Pain across the lower back and hips
Occasionally pain into the leg
Worse with prolonged activity
Typically a history of back injuries
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pain vs damage (?)
like OA, can be much pain with little damage, vs little pain with much damage
(???)
"Imaging does not always correlate with symptoms"
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DDD SSx 2
Pain
From compression of structures
Nerve roots, ligaments, dura mater (meninges), blood vessels
Starts centrally where disc is affected and may spread laterally and increase in intensity
Gluteal area, thigh, leg, foot
Usually worse in the morning
Usually deep and poorly localized
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Scoliosis and DDD (?)
Scoliosis
FUNCTIONAL SCOLIOSIS
90% have a lateral shift away from pain (reduce compression)
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Functional scoliosis and Disc herniation
Transient functional scoliosis is typically a temporary response to pain in the body, most often caused by a herniated disc.
An individual may completely change their posture based on the pain they are experiencing, which could cause a curve without rotation in their spine.
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DDD SSx 3
Neurological signs
---> Decreased sensation
---> Motor weakness
---> Decreased reflexes
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symptoms get worse with...
Symptoms typically worsen with:
Flexion, sitting, coughing, bearing down
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symptoms get better with...
Symptoms typically decrease with:
Extension, standing, walking
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Cauda Equina
Cauda Equina = “horse tail”
Formed by nerve roots caudal to the level of spinal cord termination at L2
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Cauda Equina Syndrome
Syndrome due to compression of cauda equina
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Cauda Equina Syndrome cause
Trauma, infection, tumour, DJD, DDD/herniation, spinal anesthesia, AS, idiopathic
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Cauda Equina Syndrome SSx
Pain, numbness and tingling, mm weakness, poor lower body reflexes, saddle anaesthesia
Severe cases can lead to paralysis if not treated
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Lumbarization
Nonfusion of the first and second segments of the sacrum
One additional articulated vertebra (L6)
Sacrum consists of one less segment
May be asymptomatic and clinically insignificant
May lead to altered biomechanics
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Sacralization
Developmental abnormality in which the first sacral segment becomes fused with the fifth lumbar vertebra
Leads to extra long sacrum and four lumbar vertebrae
May be asymptomatic and clinically insignificant
May lead to altered biomechanics
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