中国医科大学：《妇产科学》课程教学资源（PPT课件讲稿，英文版）Dystocia Second part：abnormalities of birth canal

Dys dystocia Second part: abnormalities of birth canal

Dystocia Second part: abnormalities of birth canal

Pelvic contraction Birth canal bony canal Soit cana abnormal bony canal: pelvic contraction any contraction of the pelvic diameters that diminishes the capacity of the pelvis can creat dystocia during labor

Pelvic contraction Birth canal – bony canal – soft canal abnormal bony canal: pelvic contraction – any contraction of the pelvic diameters that diminishes the capacity of the pelvis can creat dystocia during labor

Classification Contraction of the pelvic inlet contraction of the midpelvis and pelvic outlet general contraction of the pelvis pelvic deformities

Classification Contraction of the pelvic inlet contraction of the midpelvis and pelvic outlet general contraction of the pelvis pelvic deformities

Contracted pelvic inlet Anteroposterior d<lOcm diagonal conjugate d<1l.5cm external conjugate d<l 8cm simple flat pelvIs rickets flat pelvis

Contracted pelvic inlet Anteroposterior d<10cm diagonal conjugate d<11.5cm external conjugate d<18cm – simple flat pelvis – rickets flat pelvis

Contracted midpelvis Midpelvis: from inferior margin of the symphysis pubis through the ischial spines touches the sacrum near the junction of the 4th and 5th vertebrae contraction: interischial spinous diameter is smaller than &cm(spines are prominent, the pelvic Side walls converge or the sacrosciatic notch is narrow)

Contracted midpelvis Midpelvis: from inferior margin of the symphysis pubis through the ischial spines,touches the sacrum near the junction of the 4th and 5th vertebrae contraction: interischial spinous diameter is smaller than 8cm(spines are prominent, the pelvic side walls converge or the sacrosciatic notch is narrow)

Contracted pelvic outlet Defination diminution of the interischial tuberous diameter to &cm or less 2 triangles baseof both interischial tuberous diameter anterior triangle posterior triangle

Contracted pelvic outlet Defination: diminition of the interischial tuberous diameter to 8cm or less. 2 triangles: – baseof both: interischial tuberous diameter – anterior triangle – posterior triangle

picture 1 CHAPTER 19 DYSTOCIA DUE TO PELVIC CONTRACTION 465> Ant sagittal 7.7 cm 55cm系 FIPost. sagittal outlet of case shown in Figure 19-4. Eye is quite narrow (5.5 cm), vaginal delivery is possible because of the long(10 cm)posterior sagittal diameter. (int tth diam. intertuberous diameter, Sym. s symphysis pubis: S-5= fifth sacri

picture1

Outlet contraction without concomitant midplane contraction is rare Funnel shaped pelvis transversely contracted pelvis

Outlet contraction without concomitant midplane contraction is rare Funnel shaped pelvis transversely contracted pelvis

General contraction of the pelvis 2cm or more shorter than normal e Pelvic deformities osteomalacic pelvis obliquely contracted pelvis

•General contraction of the pelvis •2cm or more shorter than normal •Pelvic deformities •osteomalacic pelvis •obliquely contracted pelvis

Effects on mather and fetus MOTHER Inlet Malpresentation and malposition prolonged labor insufficient uterine contraction midpelvis and outlet persistant occipitotransverse or occipitoposterior position fistula formation Intrapartum infection threatening rupture or rupture

Effects on mather and fetus MOTHER:Inlet – Malpresentation and malposition – prolonged labor – insufficient uterine contraction midpelvis and outlet – persistant occipitotransverse or occipitoposterior position – fistula formation – intrapartum infection – threatening rupture or rupture