Ob-gyne: The Bony Pelvis
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Parts of the innominate bone, except:
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Ileum
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Ilium
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Ischium
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Pubis
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This OB-Gyne quiz focuses on the bony pelvis, exploring its anatomy through various questions. It assesses knowledge on pelvic joints, planes, and landmarks relevant to fetal presentation, crucial for medical students and professionals in obstetrics.
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- 2.
The ff are joints of the pelvis, except
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Saccroiliac joints
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Saccrovertebral joint
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Saccrococcygeal joint
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Symphysis pubis
Correct Answer
A. Saccrovertebral jointExplanation
The saccrovertebral joint is not a joint of the pelvis. The pelvis consists of the sacroiliac joints, saccrococcygeal joint, and symphysis pubis. The saccrovertebral joint refers to the joint between the sacrum and the vertebrae of the spine, which is not part of the pelvis.Rate this question:
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- 3.
The ff statements are true, except:
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The pelvic diameter is greatest in the dorsal lithotomy position
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The pelvic joints relaxes during pregnancy due to hormonal changes
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The increase in diameter of pelvic inlet is allowed when the sacrum rotates posteriorly
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This laxity began to regress immediately after parturition and that regression was completed within 3 to 5 months
Correct Answer
A. The increase in diameter of pelvic inlet is allowed when the sacrum rotates posteriorlyExplanation
It is the diameter of the pelvic outlet that is increased. This is most likely the reason that McRoberts maneuver is often successful in releasing an obstructed shoulder in shoulder dystocia.Rate this question:
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- 4.
It is the landmark used in assessing the level to which the presenting part of the fetus has descended into the true pelvis:
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Iliac spines
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Ischial tuberosity
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Iliopectinate line
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Ischial spines
Correct Answer
A. Ischial spinesExplanation
The ischial spines are used as a landmark to assess the level to which the presenting part of the fetus has descended into the true pelvis. These bony projections can be felt during a vaginal examination and provide information about the progress of labor and the position of the baby. By determining the position of the ischial spines, healthcare providers can gauge how far the baby's head has descended and make decisions regarding the management of labor.Rate this question:
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- 5.
Roomiest plane of the pelvis:
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Plane of the pelvic inlet
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Plane of the pelvic outlet
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Plane of the midpelvis
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Plane of greatest pelvic dimension
Correct Answer
A. Plane of greatest pelvic dimensionExplanation
The plane of greatest pelvic dimension refers to the widest part of the pelvis, which allows for the most spacious area within the pelvis. This plane is important for childbirth as it provides enough room for the baby to pass through the birth canal. It is also relevant for surgical procedures involving the pelvis, as it allows for easier access and maneuverability.Rate this question:
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- 6.
Plane with the least pelvic dimensions:
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Plane of the pelvic inlet
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Plane of the pelvic outlet
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Plane of the midpelvis
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Plane of greatest pelvic dimension
Correct Answer
A. Plane of the midpelvisExplanation
The plane of the midpelvis is the correct answer because it represents the middle section of the pelvis, which typically has smaller dimensions compared to the pelvic inlet and outlet. The pelvic inlet is the upper opening of the pelvis, while the pelvic outlet is the lower opening. These two planes usually have larger dimensions to accommodate childbirth. The plane of greatest pelvic dimension is not the correct answer because it implies the largest dimensions, which is not true for the midpelvis.Rate this question:
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- 7.
Boundaries of the pelvic inlet:
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Sacral promontory
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Iliopectinate lines
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Pubic symphysis
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All of the above
Correct Answer
A. All of the aboveExplanation
The boundaries of the pelvic inlet include the sacral promontory, iliopectinate lines, and pubic symphysis. These structures define the upper opening of the pelvis and help to separate the pelvic cavity from the abdominal cavity. The sacral promontory is a bony ridge on the sacrum, the iliopectinate lines are the junctions between the ilium and pubis bones, and the pubic symphysis is the joint between the two pubic bones. Together, these boundaries form the complete outline of the pelvic inlet.Rate this question:
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- 8.
True of the pelvic inlet:
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Obstetrical conjugate is the shortest AP diameter
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True conjugate is the shortest AP diameter
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Diagonal conjugate is the shortest AP diameter
Correct Answer
A. Obstetrical conjugate is the shortest AP diameterExplanation
The obstetrical conjugate refers to the distance between the sacral promontory and the back of the pubic symphysis. It is an important measurement in obstetrics as it determines the size of the pelvic inlet. In this case, the correct answer states that the obstetrical conjugate is the shortest AP (anteroposterior) diameter. This means that it is the shortest distance from the front to the back of the pelvic inlet.Rate this question:
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- 9.
Measured during pelvic examination:
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True conjugate
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Anatomic conjugate
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Obstetric conjugate
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Diagonal conjugate
Correct Answer
A. Diagonal conjugateExplanation
The diagonal conjugate is measured during a pelvic examination. It is the distance between the lower border of the symphysis pubis and the sacral promontory. This measurement is important in obstetrics as it helps determine the adequacy of the pelvic inlet for childbirth. It provides an estimation of the true conjugate, which is the narrowest diameter of the pelvic inlet. The diagonal conjugate measurement is commonly used in clinical practice to assess the pelvic dimensions and plan for a safe delivery.Rate this question:
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- 10.
The shortest AP diameter of the pelvic inlet:
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True conjugate
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Anatomic conjugate
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Obstetric conjugate
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Diagonal conjugate
Correct Answer
A. Obstetric conjugateExplanation
The shortest AP diameter of the pelvic inlet is referred to as the obstetric conjugate. This measurement is important in obstetrics as it determines the size of the pelvic inlet and whether a baby can pass through during childbirth. The obstetric conjugate is measured from the sacral promontory to the lower border of the pubic symphysis and is typically shorter than the true conjugate, which is measured from the sacral promontory to the upper border of the pubic symphysis. The anatomic conjugate is measured from the sacral promontory to the posterior surface of the pubic symphysis, while the diagonal conjugate is measured from the sacral promontory to the lower border of the pubic symphysis, but it is not the shortest AP diameter of the pelvic inlet.Rate this question:
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- 11.
Average length of the true conjugate:
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10 cm
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11 cm
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12 cm
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13 cm
Correct Answer
A. 11 cmExplanation
The average length of the true conjugate is 11 cm.Rate this question:
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- 12.
Average length of the obstetric conjugate:
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10 cm
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11 cm
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12 cm
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13 cm
Correct Answer
A. 10 cmExplanation
The average length of the obstetric conjugate is 10 cm. The obstetric conjugate is the smallest diameter of the pelvic inlet, and it is measured from the promontory of the sacrum to the upper border of the pubic symphysis. This measurement is important in obstetrics as it helps determine if the pelvis is adequate for vaginal delivery. A length of 10 cm suggests a relatively smaller pelvis, which may require further assessment to ensure a safe delivery.Rate this question:
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- 13.
Average length of the diagonal conjugate:
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10 cm
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11 cm
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12 cm
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13 cm
Correct Answer
A. 12 cmExplanation
The average length of the diagonal conjugate is 12 cm. This means that when you take the length of all the diagonal conjugates and add them together, and then divide that sum by the number of diagonal conjugates, the result is 12 cm.Rate this question:
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- 14.
A 22 y.o, G2P1 has 13 cm diagonal conjugate diameter. What are the lengths of the true and obstetric conjugates?
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11.8 cm and 11-11.5 cm
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11.5 cm and 11-11.8 cm
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11.5 cm and 11.5-11.8 cm
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11.8 cm and 11.5-11.8 cm
Correct Answer
A. 11.8 cm and 11-11.5 cmExplanation
The diagonal conjugate diameter is the distance from the sacral promontory to the lower border of the symphysis pubis. The true conjugate is the distance from the sacral promontory to the upper border of the symphysis pubis, while the obstetric conjugate is the distance from the sacral promontory to the midpoint of the symphysis pubis. In this case, the diagonal conjugate diameter is 13 cm, so the true conjugate would be slightly longer than that, around 11.8 cm. The obstetric conjugate would be slightly shorter, around 11-11.5 cm. Therefore, the answer is 11.8 cm and 11-11.5 cm.Rate this question:
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- 15.
The interspinous diameter is:
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10 cm or more
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11.5 cm
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11 cm
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12 cm
Correct Answer
A. 10 cm or moreExplanation
The interspinous diameter refers to the distance between the spinous processes of the vertebrae in the spine. The correct answer is "10 cm or more" because it indicates that the interspinous diameter should be equal to or greater than 10 cm. This suggests that the space between the spinous processes is wide enough, which is important for proper spinal alignment and movement.Rate this question:
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- 16.
The posterior sagittal diameter measures ___ in average
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3.5 cm
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4 cm
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4.5 cm
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5 cm
Correct Answer
A. 4.5 cmExplanation
The correct answer is 4.5 cm. The posterior sagittal diameter refers to the measurement of the distance from the back of the head to the sacrum, which is the triangular bone at the base of the spine. On average, this measurement is 4.5 cm.Rate this question:
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- 17.
The ff. statements are true if midpelvic contraction is suspected, except:
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Ischial spines are less prominent
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Pelvic sidewalls are convergent
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Concavity of the sacrum is shallow
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Bi-ischial diameter of the pelvic outlet is less than 8 cm
Correct Answer
A. Ischial spines are less prominentExplanation
If midpelvic contraction is suspected, the ischial spines would be more prominent rather than less prominent. This is because midpelvic contraction refers to a narrowing of the pelvic outlet, which would cause the ischial spines to become more prominent as they are pushed closer together. Therefore, the statement "ischial spines are less prominent" is not true if midpelvic contraction is suspected.Rate this question:
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- 18.
AP diameter of the pelvic outlet:
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9.5-10 cm
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9.5-10.5 cm
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9.5-11 cm
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9.5-11.5 cm
Correct Answer
A. 9.5-11.5 cmExplanation
The AP diameter of the pelvic outlet refers to the measurement from the front to the back of the pelvic outlet. The correct answer range of 9.5-11.5 cm indicates that this measurement can vary within this range. This range allows for individual variation in pelvic size and shape, accommodating for the passage of the baby during childbirth.Rate this question:
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- 19.
4 basic types of pelvices:
Correct Answer
gynecoid andthropoid android platypelloidExplanation
The given answer lists the four basic types of pelvis: gynecoid, andthropoid, android, and platypelloid. These types refer to different shapes and structures of the pelvis, which can have implications for childbirth and overall pelvic health. The gynecoid pelvis is the most common and ideal type for childbirth, while the andthropoid, android, and platypelloid pelvises have their own unique characteristics and potential challenges during childbirth.Rate this question:
- 20.
Most prevalent pelvic type:
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Gynecoid
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Anthropoid
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Android
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Platypelloid
Correct Answer
A. GynecoidExplanation
The most prevalent pelvic type is gynecoid. This type of pelvis is commonly found in women and is considered the most favorable for childbirth. The gynecoid pelvis has a round shape with a wide pelvic inlet and a generous pelvic outlet, allowing for easy passage of the baby during delivery. This pelvic type is associated with a lower risk of complications during childbirth compared to other types such as anthropoid, android, or platypelloid pelvis.Rate this question:
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- 21.
If the diagonal conjugate is greater than 11.5 cm, it is justifiable to assume that the pelvic inlet is of adequate size for vaginal delivery of a normal-sized fetus.
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True
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False
Correct Answer
A. TrueExplanation
If the diagonal conjugate, which is a measurement of the distance between the sacral promontory and the lower border of the symphysis pubis, is greater than 11.5 cm, it suggests that the pelvic inlet is large enough to allow for a normal-sized fetus to pass through during vaginal delivery. This measurement is commonly used to assess the adequacy of the pelvis for childbirth. Therefore, the statement is true.Rate this question:
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Current Version
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Mar 21, 2023Quiz Edited by
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Sep 18, 2010Quiz Created by
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