Flat stenosis of birth canal

Introduction The shortening of any one or several of the pelvis is called pelvic stenosis. The pelvis can be narrowed simultaneously in one or more of the three planes of the entrance, the middle pelvis, and the exit. Stenosis at the entrance: Most of the performance is that the anteroposterior diameter of the entrance plane is narrow, ie flat stenosis.

Cause

Mostly the result of childhood rickets.

an examination

Related inspection

Obstetrics B super obstetric examination vaginal gynecological routine examination gynecological ultrasound examination gynecological examination

History

If you have the following medical history, such as vitamin D deficiency, osteomalosis, poliomyelitis, spinal and hip tuberculosis, severe thoracic or spinal deformity, pelvic fractures, and cesarean section, vaginal surgery midwifery, repeated hip A maternal, stillbirth, or neonatal birth injury in a position or position should be carefully examined for pelvic abnormalities.

2. Physical examination

(1) General examination: a short stature, less than 145cm of the mother, the possibility of small stenosis of the pelvis is greater. The body is thick, the neck is short, and the bones are masculine. It is not only affected by the thicker bone, but also the funnel-type stenosis. The lower limbs are unequal in length, which can lead to pelvic deformities. Therefore, it is necessary to carefully check whether there are any lower limb or spinal diseases that affect the pelvic morphology, whether there is vitamin D deficiency or sequelae of pelvic fractures.

(2) Pelvic measurement:

1 extra-pelvic measurement:

A. The outer diameter of the shame is <18cm, suggesting that the posterior diameter of the entrance is narrow, often a flat pelvis.

B. The diameter of the ischial tuberosity <7.5cm, the outlet diameter should be considered narrow, often accompanied by pelvic stenosis.

C. The ischial nodular diameter + posterior sagittal diameter <15cm or the pubic arch angle is acute and the pubic arch is low, also suggesting that the outlet is narrow.

D. Mie's diamond shape is asymmetrical, and the sides are not equal, which may be a skewed pelvis. E. Measurement of each diameter outside the pelvis is 2 cm or more smaller than the normal value, suggesting a small pelvic stenosis.

2 pelvic measurement: If pelvic stenosis is suspected when measuring outside the pelvis, intrapelvic measurements should be taken in late pregnancy or after delivery. The internal measurement shall be carried out after disinfection of the vulva and vagina after wearing the middle finger of the disinfecting glove and indicating the transvaginal examination.

A. Diagonal diameter: It is the distance from the lower edge of the pubic symphysis to the iliac crest. The normal value is 12.5~13cm. The diagonal diameter minus 1.5cm is equal to the back diameter of the pelvic entrance, which is the true combined diameter.

B. Ischial spine diameter: also known as the middle pelvis transverse diameter, this diameter is not easy to measure, the following methods can be used: a. measured with De-Lee pelvis measuring device, but the end of the device is difficult to fix, so it is difficult to check Accurate; b. It was suggested that the finger touched one side of the ischial spine in the internal diagnosis and swept to the other side. The length was estimated by the hand index, but it was not accurate enough. Clinical estimation methods can not be used to accurately understand the diameter of the ischial spine: a. Consider the diameter of the posterior superior iliac spine, ie, the diameter of the Mie diamond, plus 1 cm as the diameter of the ischial spine. b. An easier way is to divide the degree of tibial spine into 3 levels to indicate the length of the ischial spine. Grade I: The ischial spine is relatively flat, and the diameter of the ischial spine is longer; Grade II: the ischial spine is moderately prominent, and the ischial spine diameter is also medium length; Grade III: the ischial spine sharply protrudes, and the ischial spine diameter is short. c. Refer to the length of the ischial nodule diameter.

C. The anterior and posterior diameter of the pelvis: first determine the appendix joint, then use the internal fingertips to follow the joint upwards, and save the 1cm over the humerus. Here, the junction of the 4th and 5th atlas is the post-measure of the measurement. The site is still the lower edge of the pubic symphysis. The average anteroposterior diameter of the middle pelvis was 12.2 cm.

D. Middle pelvic sagittal diameter: This diameter can not be directly measured, but it can be represented by the width of the bottom of the sciatic notch. It can accommodate 3 horizontal fingers as normal. If 2 horizontal fingers indicate that the sagittal diameter of the middle pelvis is obviously shortened. The width of the notch is more accurate with the anal examination, and the vaginal examination is not easy to reach, especially the primipara.

E. Shame joint back angle: This angle should be >156o. If you feel that the back angle of the shame joint is wider, it means the female pelvis. If it is smaller, it is the sputum type or the male pelvis.

In summary, the clinical situation can be determined by the following conditions to determine the stenosis of the middle pelvis: A. sciatic spine grade II or III; B. sciatic notch bottom width <4.5cm (<3 horizontal finger); C. ischial tuberosity The diameter is 7.5cm. A diagnosis of middle pelvic stenosis can be diagnosed with 2 or more of them. Anal digital examination to understand the latter part of the pelvis is often more accurate than the vaginal examination, and simple and easy, actually a method of measurement in the pelvis.

Other auxiliary inspections:

1. X-ray pelvis measurement

2.B super pelvic measurement

3. Computed tomography (CT) pelvic measurement

4. Magnetic resonance imaging (MRI) pelvic measurement

Differential diagnosis

Should be identified with a simple flat pelvis. The project area is identified from the entrance plane, the anteroposterior diameter of the entrance plane, the plane below the entrance plane, and the concavity of the tibia. The simple flat inlet plane is horizontally flat and round, and the flattened flat is kidney-shaped; the anteroposterior diameter of the entrance plane is shortened, and the latter is shortened; the lower plane of the entrance plane is normal, the latter is gradually enlarged; the concavity of the tibia, the former has In a certain degree of curvature, the latter's tibia straightens back to the back.

History

If you have the following medical history, such as vitamin D deficiency, osteomalosis, poliomyelitis, spinal and hip tuberculosis, severe thoracic or spinal deformity, pelvic fractures, and cesarean section, vaginal surgery midwifery, repeated hip A maternal, stillbirth, or neonatal birth injury in a position or position should be carefully examined for pelvic abnormalities.

2. Physical examination

(1) General examination: a short stature, less than 145cm of the mother, the possibility of small stenosis of the pelvis is greater. The body is thick, the neck is short, and the bones are masculine. It is not only affected by the thicker bone, but also the funnel-type stenosis. The lower limbs are unequal in length, which can lead to pelvic deformities. Therefore, it is necessary to carefully check whether there are any lower limb or spinal diseases that affect the pelvic morphology, whether there is vitamin D deficiency or sequelae of pelvic fractures.

(2) Pelvic measurement:

1 extra-pelvic measurement:

A. The outer diameter of the shame is <18cm, suggesting that the posterior diameter of the entrance is narrow, often a flat pelvis.

B. The diameter of the ischial tuberosity <7.5cm, the outlet diameter should be considered narrow, often accompanied by pelvic stenosis.

C. The ischial nodular diameter + posterior sagittal diameter <15cm or the pubic arch angle is acute and the pubic arch is low, also suggesting that the outlet is narrow.

D. Mie's diamond shape is asymmetrical, and the sides are not equal, which may be a skewed pelvis.

E. Measurement of each diameter outside the pelvis is 2 cm or more smaller than the normal value, suggesting a small pelvic stenosis.

2 pelvic measurement: If pelvic stenosis is suspected when measuring outside the pelvis, intrapelvic measurements should be taken in late pregnancy or after delivery. The internal measurement shall be carried out after disinfection of the vulva and vagina after wearing the middle finger of the disinfecting glove and indicating the transvaginal examination. A. Diagonal diameter: It is the distance from the lower edge of the pubic symphysis to the iliac crest. The normal value is 12.5~13cm. The diagonal diameter minus 1.5cm is equal to the back diameter of the pelvic entrance, which is the true combined diameter.

B. Ischial spine diameter: also known as the middle pelvis transverse diameter, this diameter is not easy to measure, the following methods can be used: a. measured with De-Lee pelvis measuring device, but the end of the device is difficult to fix, so it is difficult to check Accurate; b. It was suggested that the finger touched one side of the ischial spine in the internal diagnosis and swept to the other side. The length was estimated by the hand index, but it was not accurate enough. Clinical estimation methods can not be used to accurately understand the diameter of the ischial spine: a. Consider the diameter of the posterior superior iliac spine, ie, the diameter of the Mie diamond, plus 1 cm as the diameter of the ischial spine. b. An easier way is to divide the degree of tibial spine into 3 levels to indicate the length of the ischial spine. Grade I: The ischial spine is relatively flat, and the diameter of the ischial spine is longer; Grade II: the ischial spine is moderately prominent, and the ischial spine diameter is also medium length; Grade III: the ischial spine sharply protrudes, and the ischial spine diameter is short. c. Refer to the length of the ischial nodule diameter.

C. The anterior and posterior diameter of the pelvis: first determine the appendix joint, then use the internal fingertips to follow the joint upwards, and save the 1cm over the humerus. Here, the junction of the 4th and 5th atlas is the post-measure of the measurement. The site is still the lower edge of the pubic symphysis. The average anteroposterior diameter of the middle pelvis was 12.2 cm.

D. Middle pelvic sagittal diameter: This diameter can not be directly measured, but it can be represented by the width of the bottom of the sciatic notch. It can accommodate 3 horizontal fingers as normal. If 2 horizontal fingers indicate that the sagittal diameter of the middle pelvis is obviously shortened. The width of the notch is more accurate with the anal examination, and the vaginal examination is not easy to reach, especially the primipara.

E. Shame joint back angle: This angle should be >156o. If you feel that the back angle of the shame joint is wider, it means the female pelvis. If it is smaller, it is the sputum type or the male pelvis.

In summary, the clinical situation can be determined by the following conditions to determine the stenosis of the middle pelvis: A. sciatic spine grade II or III; B. sciatic notch bottom width <4.5cm (<3 horizontal finger); C. ischial tuberosity The diameter is 7.5cm. A diagnosis of middle pelvic stenosis can be diagnosed with 2 or more of them. Anal digital examination to understand the latter part of the pelvis is often more accurate than the vaginal examination, and simple and easy, actually a method of measurement in the pelvis.

Other auxiliary inspections:

1. X-ray pelvis measurement

2.B super pelvic measurement

3. Computed tomography (CT) pelvic measurement

4. Magnetic resonance imaging (MRI) pelvic measurement

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