Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Anatomy of the Individual > Skeletal Variation > Flashcards

Skeletal Variation Flashcards

(105 cards)

Start Studying
1
Q

How can bone remodelling be described generally?

A

Bone formation and degradation as an ongoing process throughout life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where is bone created?

A

In skeletal tissues that are supposed to ossify

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What condition is the formation of bony in tissues that are not normally bony?

A

Myositis ossificans circumscripta:

- Traumatica

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Give examples of studies into formation of bone in non-bony tissues?

A

Sodl et al., (2008):
- Repeated trauma to quadriceps during college hazing resulted in myositis ossificans circumscripta
Salter, (1999)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How can myositis ossificans circumscripta appear on imaging?

A

Opacity on x-ray

Oedema on MRI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What type of bone is formed following trauma?

A

Woven

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Give examples of studies that show the difference between bony variation and bony pathology?

A

Chakraborty and Bhattacharya, (2012):
- Describe brachydactyly of 3rd and 4th digits in right foot
- VARIATION
Singh and Downing, (2005):
- ‘Empty’ toe
- Closed degloving injury displacing 5th toe medially
- NOT variation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How do sternal foramina arise?

A

Incomplete fusion of multiple ossification centres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What risks do sternal foramina pose?

A

Risk of injury to deep structures during:

  • Bone marrow aspiration
  • Acupuncture
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the study on sternal foramina by Lloret, (2004)?

A

Anthropological study
Two holes in sternum:
- One with irregular edged and fracture lines = Gunshot wound
- One with smooth, rounded edges (sternal foramen)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What potential reason do Kumarasamy and Agrawal, (2011) give for a large sternal foramen?

A

Two failed ossification centres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Os odontoideum is an area of debate as to whether or not its variation or traumatic. What is the reasoning behind both?

A

Variation:
- Congenital condition representing centrum of pro-atlas or atlas
OR
Trauma:
- Chronic non-united fracture of odontoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What can os odontoideum result in according to 3 case studies by Limo et al., (2008)?

A

Flexion-extension may cause ossicle and C1 movement relative to C2:
- Results in atlantoaxial instability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What was measured to quantify the instability in the case studies by Limo et al., (2008)?

A

Interval between:
- Posterior margin of anterior tubercle of C1
AND
- Anterior margin of base of dens and body of C2
This interval is then compared to neutral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does the study by Candan et al., (2014) describe?

A

Traumatic os odontoideum in a 3 year old boy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What do non-metric traits result from?

A

Genetic factors

Environmental factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are non-metric traits?

A

Traits that are either present or not

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Regarding the uses for skeletal variation, what did Eroglu, (2008) use?

A

Used frequency of metopism to obtain information about gene flow in Anatolian populations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is metopism?

A

Presence of a persistent frontal suture = A metopic suture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What did Ajmani et al., (1983) study?

A

Incidence of metopic suture in adult Nigerian skulls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What did Dodo, (1974) study?

A

Hyperostotic features more common in AInu than Japanese population

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What supernumerary ossicle variations of the skull were described by Hanihara and Ishida, (2001a)?

A

Ossicle at the lambda
Parietal bone notch
Asterionic bone
Occipitomastoid bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What hypostotic variations of the skull were described by Hanihara and Ishida, (2001b)?

A 
Tympanic dehiscence
Ovale-spinosum confluence
Metopism
Transverse zygomatic suture vestige
Biasteronic suture
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What variations in the bony structure of the skull did Seema and Mahajan, (2014) find?

A 
Metopism
Multiple Wormian (intrasutral) bones at lambda
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What variation do Udupi and Srinivasan, (2011) describe?
Large interparietal bone
26
What did Karau et al., (2010) investigate?
Prevalence of atlas vertebral bridges in Kenyans: | - Bony outgrowths over V3 segment of vertebral artery
27
What were the results of the Karau et al., (2010) study?
Complete atlas vertebral bridges more common in females: | Atlas vertebral bridges predispose to vertebrobasilar insufficiency
28
What did Nambiar et al., (1999) study?
Variation in frontal sinuses for forensic indentification
29
What is the postcranial axial skeleton formed from?
Somites: | - Mesenchyme = Mesenchymal origin
30
What part of the somite does connective tissue of the skin form from?
Lateral and superficial dermatome
31
What part of the somite does muscle form from?
Myotome
32
What part of the somite does the axial skeleton (including vertebrae and ribs) form from?
Medial and ventral sclerotome
33
What does sclerotome growth towards midline form?
Vertebral body
34
What does dorsal sclerotome growth do?
Encloses neural tube
35
What does ventrolateral sclerotome growth form?
Costal processes
36
What do the costal processes form in the cervical region?
Fuse with transverse process and vertebral body = Foramen transversarium
37
What do the costal processes form in the thoracic region?
Ribs
38
What do the costal processes form in the lumbar region?
Fuse with transverse processes
39
What do the costal processes form in the sacral region?
Pars lateralis (flat plates)
40
What genes regulate what the costal processes form in each region?
Hox genes
41
What study investigated the fates of costal processes depending on location?
Chernoff and Rogers, (2004)
42
Regarding the cervical prevalence of supernumerary ribs, what are the results of a study by Kurihara et al., (1999)?
Cervical (C7) rib in 0.5% of population | C7 rib more common in females
43
Regarding the prevalence of cervical supernumerary ribs, what are the results of a study by Viertal et al., (2012)?
Cervical ribs in 2% of population Twice as common in females 40.3% bilateral Higher incidence in African American population
44
How do cervical supernumerary ribs present according to the study by Viertal et al., (2012)?
``` Often asymptomatic Brachial plexus/Subclavian vessel compression: - Thoracic outlet syndrome - In 8.3% of cervical rib patients Underreported on CT ```
45
What are the types of intrathoracic ribs? (Reference?)
Type I = Supernumerary intrathoracic rib arising from: - Ia = Vertebral body - Ib = Part of rib close to vertebral body Type II = Bifid intrathoracic rib Type III = Rib locally depressed into thoracic cavity (Kamano et al., 2006)
46
How do intrathoracic ribs present?
Often asymptomatic | Pain if attached to diaphragmatic pleura
47
How many cases of intrathoracic rib have been reported?
40 cases in literature since 1947
48
What might an intrathoracic rib be mistaken for?
A bone tumour Pleural calcified plaque Pulmonary vein variant
49
What is the prevalence of lumbar ribs?
0.04-2.0%
50
Describe sacral/pelvic ribs
Sacral/Pelvic ribs develop bone (with cortex) in soft tissues adjacent to sacrum which may pseudoarticulate
51
In what state might sacral or pelvic ribs cause issues?
Pregnancy
52
What does the Schumacher et al., (1992) study show is linked to rub anomalies?
Rib anomalies associated with malignancy: - 242 rib anomalies in 218/1000 kids with tumours (21.8%) - Only 11/200 kids without malignancy had rib anomalies (5.5%)
53
What are cervical ribs associated with according to the Schumacher et al., (1992) study?
``` Brain tumours (27.4%) Leukaemia (26.8%) ```
54
How did the patient of a Kazanci et al., (2012) study present?
No functional issues | Presented following injury
55
What was the variation seen in the Kazanci et al., (2012) case study?
Unilateral C6 hyperplasia of lamina Schisis of spinal process: - Gap between 2 parts of process Spinous process 15cm long (when removed)
56
How could the case seen in the Kazanci et al., (2012) study be differentiated from trauma by imaging?
CT would show: - No pseudoarthritis - No ossifying haematoma MRI would show no ossifying haematoma
57
What is the average length of the styloid process and where does the tip lie?
2.5cm long | Tip between ECA and ICA
58
Regarding a styloid process, what did the case study by Kolagi et al., (2010) describe?
8cm long styloid process: - 5cm bone - 3cm ossified stylohyoid ligament
59
What implications can styloid processes longer than 3cm have?
Difficulty swallowing Carotid artery compression Foreign body sensation
60
What features of a long styloid process are important regarding whether or not it will result in signs/symptoms?
Direction | Curvature
61
What are the epidemiological stats for hyperplasia of the styloid process (Kolagi et al., 2010)?
Prevalence = 4-7% 4x more common in males 75% of cases are bilateral
62
What are the types of upper limb dysplasias?
Osseous Musculotendinous Neuromuscular
63
What does radial deficiency result in?
Longitudinal deficiency in embryonic limb bun leading to defects of: - Radius - Carpals - Radial rays (especially thumb)
64
What does ulnar deficiency result in?
Longitudinal deficiency in embryonic limb bun leading to defects of: - Ulna - Carpals
65
What other systems may be affected in radial and ulnar deficiency?
Renal Cardiac GI
66
Regarding radial and ulnar deficiency, what did radiographs in a study by Manske, (1996) show?
``` Radiograph of ulnar deficiency: - Abnormal radius - Absent carpals Radiograph of radial absence: - Centralised ulna (surgically) = More stable wrist ```
67
What ribs are usually affected as shortened midthoracic ribs?
6, 7 or 8
68
What is the prevalence of shortened midthoracic ribs?
16% Right side = 8% Left side = 1% Bilateral = 7%
69
What is the reference for shortened midthoracic ribs?
Kurihara et al., (1999)
70
What is the embryological origin of shortened midthoracic ribs?
Early fusion of epiphyseal centre
71
What are the clinical issues associated with shortened midthoracic ribs?
There are none
72
What are the functions of bone?
Protection/Support Muscle attachment Movements (joints
73
What are the surgical implications of bony variation?
Transplantation issues | Implantation of prostheses/Fixation
74
What variation is described in a case study by Varrichio et al., (2013)?
Obturator nerve running in osseous tunnel from near ischial spine to normal pelvic aspect of the obturator canal
75
What are the implications of the variation described by Varrichio et al., (2013)?
None in this case | May result in issues if pelvic fracture
76
What is the prevalence of bifid ribs?
0.15-3.4%
77
What sort of defect is bifid ribs? What other defects may it be associated with because of this?
Mesenchymal Other defects: - Cardiac - Renal
78
What are the implications of bifid ribs?
Often asymptomatic | May affect NVB branching and rib counting
79
What can syntosis (fusion) of ribs result in? (Reference?)
Compression of intercostal NVB Reduced chest expansion = Respiratory issues (Gupta et al., 2009)
80
What does bony absence result in?
Leaves soft tissues vulnerable to damage
81
How does spina bifida occulta arise?
Incomplete midline dorsal bony fusion
82
What is a possible clinical implication of spina bifida occulta? (Reference?)
Unprotected spinal cord: - Dural puncture if given epidural anaesthesia (Senoglu et al., 2008)
83
According to a study by Senoglu, (2007), how can a missing posterior arch of the atlas present?
Asymptomatic | Transient neurological symptoms
84
Bony variation may also result in what issues?
Joint instability | Risk of injury during sport
85
What variations may result in joint instability and how?
Aplasia = No bone to form joint | Malformations of articular surface
86
What did Tubbs et al., (2005) study regarding bony variation and joint stability?
Duplication of occipital condyles
87
What were the findings in the Tubbs et al., (2005) study?
Extra occipital condyles results in craniocervical instability Additional bony prominences form in an attempt to stabilise
88
What study disagrees with the Tubbs et al., (2005) study on atlanto-occipital joint stability in the presence of additional condyles?
Kunicki and Ciszek, (2005)
89
What did Hemamalini, (2014) study?
Atlanto-occipital fusion
90
What anomalies of the atlanto-occipital joint are major enough to affect movement at the joint according to the Hemamalini, (2014) study?
Assimilation of the atlas | Occipitalisation of the atlas
91
What can atlanto-occipital fusion affect?
``` Can alter course of or compress: - Vertebral artery - C1 nerve (As both pass over C1 usually) Cord compression (if affecting foramen magnum) Flexion-extension of head ```
92
What bony variations may compress neurovascular structures?
Foramina overgrowth Bony tunnels Bony spurs
93
Apart from a variant bone itself compressing a neurovascular structure, what else may compress nerves/vessels? Examples?
Ligamentous material associated with it Examples: - Supracondylar spur of humerus and ligament of Struthers (Krishnamurthy and Lakshmiminarayan, 2013) - Compression of median nerve by ligament of Struthers (Suranyi, 1983)
94
What can additional bones be mistaken for?
Avulsion fracture | Disease pathology
95
What 'normal' anatomy may be mistaken for variation?
Accessory ossicles Sesamoid bones in: - Hands - Feet
96
In a study of 984 feet by Coskun et al., (2009), what did they find?
209 accessory ossicles: - 10.9% of females - 10.2% of males
97
What are the implications of an interphalangeal sesamoid bone according to Davies et al., (2003)?
Painful calluses | Migrations into a dislocated joint
98
How can bony variation affect dental procedures?
Bony landmarks | Foramina for neurovascular structures inside bone used for anaesthesia
99
What did the Hasan et al., (2010) study find that may affect dental procedures?
Bilateral absence of mental foramen
100
What racial differences are seen in the termination of mental canals?
Caucasians = More medial (1st/2nd premolar) Mongoloid population = 2nd premolar Black population = 2nd premolar/1st molar
101
How can variation affect dental implants?
Osteotomy for implant may damage inferior alveolar or mental nerve resulting in altered lip sensation
102
What are the 4 common forms of the pterion?
Sphenoparietal Sphenoparietal plus Wormian bone Frontotemporal Epipteric
103
What did Ma et al., (2012) investigate regarding the pterion?
Its relation to the middle meningeal artery
104
What did Ma et al., (2012) find regarding the thickness of the skull at the pterion?
Not always the thinnest part: - Midpoint is 4.4mm thick vs thinnest part of squamous temporal bone which is 1.1mm on lateral wall of middle cranial fossa
105
What did Ma et al., (2012) find regarding the pterion and the middle meningeal artery?
Anterior branch of MMA; - Overlies pterion in only 2/3 - Is posterior to pterion in 1/3 - Is enclosed by protective bony tunnel in 70%

Anatomy of the Individual (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions