Shoulder dystocia is a specific case of
dystociaDystocia is an abnormal or difficult childbirth or labour. Approximately a fifth of human labors have dystocia. Dystocia may arise due to incoordinate uterine activity, abnormal fetal lie or presentation, absolute or relative cephalopelvic disproportion, or a massive fetal tumor such as a...
whereby after the delivery of the head, the anterior
shoulderIn human anatomy, the shoulder joint comprises the part of the body where the humerus attaches to the scapula. The shoulder refers to the group of structures in the region of the joint....
of the
infantAn infant or baby is the term used to refer to the very young offspring of humans and other primates.-Infant:The term infant derives from the Latin word infans, meaning "unable to speak."...
cannot pass below the pubic symphysis, or requires significant manipulation to pass below the
pubic symphysisThe pubic symphysis is the midline cartilaginous joint uniting the superior rami of the left and right pubic bones. It is located anterior to the urinary bladder and superior to the external genitalia; for females it is above the vulva and for males it is above the penis. In males, the suspensory...
. It is diagnosed when the shoulders fail to deliver shortly after the fetal head. In shoulder dystocia, it is the chin that presses against the walls of the
perineumIn human anatomy, the perineum is generally defined as the surface region in both males and females between the pubic symphysis and the coccyx. The perineum is the region of the body inferior to the pelvic diaphragm and between the legs. It is a diamond-shaped area on the inferior surface of the...
One often described feature is the
turtle sign, which involves the appearance and retraction of the fetal head (analogous to a turtle withdrawing into its shell), and the erythematous, red puffy face indicative of facial flushing.
Shoulder dystocia is a specific case of
dystociaDystocia is an abnormal or difficult childbirth or labour. Approximately a fifth of human labors have dystocia. Dystocia may arise due to incoordinate uterine activity, abnormal fetal lie or presentation, absolute or relative cephalopelvic disproportion, or a massive fetal tumor such as a...
whereby after the delivery of the head, the anterior
shoulderIn human anatomy, the shoulder joint comprises the part of the body where the humerus attaches to the scapula. The shoulder refers to the group of structures in the region of the joint....
of the
infantAn infant or baby is the term used to refer to the very young offspring of humans and other primates.-Infant:The term infant derives from the Latin word infans, meaning "unable to speak."...
cannot pass below the pubic symphysis, or requires significant manipulation to pass below the
pubic symphysisThe pubic symphysis is the midline cartilaginous joint uniting the superior rami of the left and right pubic bones. It is located anterior to the urinary bladder and superior to the external genitalia; for females it is above the vulva and for males it is above the penis. In males, the suspensory...
. It is diagnosed when the shoulders fail to deliver shortly after the fetal head. In shoulder dystocia, it is the chin that presses against the walls of the
perineumIn human anatomy, the perineum is generally defined as the surface region in both males and females between the pubic symphysis and the coccyx. The perineum is the region of the body inferior to the pelvic diaphragm and between the legs. It is a diamond-shaped area on the inferior surface of the...
Signs
One often described feature is the
turtle sign, which involves the appearance and retraction of the fetal head (analogous to a turtle withdrawing into its shell), and the erythematous, red puffy face indicative of facial flushing. This occurs when the baby's shoulder is obstructed by the maternal pelvis.
Procedures
A number of obstetrical maneuvers are sequentially performed in attempt to facilitate delivery at this point, including :
- McRoberts maneuver
The McRoberts maneuver is employed in case of shoulder dystocia during childbirth and involves hyperflexing the mother's legs tightly to her abdomen. This widens the pelvis, and flattens the spine in the lower back . If this maneuver does not succeed, an assistant applies pressure on the lower...
;
- suprapubic pressure (or Rubin I)
- Rubin II or posterior pressure on the anterior shoulder
Anterior shoulder in Obstetrics refers to that shoulder of the fetus that faces the vagina of the mother during delivery. Depending upon the original position of the fetus, either the left or the right shoulder can be the anterior shoulder. It is known as the anterior shoulder as it faces the...
, which would bring the fetus in an oblique position with head somewhat towards the vagina
- Woods' screw maneuver
Woods' screw maneuver is practiced in Obstetrics when dealing with shoulder dystocia—a condition in which the fetal shoulders cannot easily pass through the pelvic inlet or outlet. In this maneuver the anterior shoulder is pushed towards the baby's chest, and the posterior shoulder is...
which leads to turning the anterior shoulder to the posterior and vice versa (somewhat the opposite of Rubin II maneuver)
- Jacquemier's maneuver (also called Barnum's maneuver), or delivery of the posterior shoulder
Posterior shoulder in Obstetrics refers to the shoulder of the fetus other than the anterior shoulder. Thus, the posterior shoulder faces the rectum of the mother during delivery. Whether left or the right shoulder becomes the posterior shoulder is dependent upon the original position of the...
first, in which the forearm and hand are identified in the birth canal, and gently pulled.
- Gaskin maneuver, named after Certified Professional Midwife, Ina May Gaskin
Ina May Gaskin is a Certified Professional Midwife , who has been described as "the mother of authentic midwifery."-Family:Gaskin was born to an Iowa Protestant family . Her father, Talford Middleton, was raised on a large Iowa farm, which was lost to a bank not long after his father’s accidental...
, involves moving the mother to an all fours position with the back arched, widening the pelvic outlet.
More drastic maneuvers include
- Zavanelli's maneuver, which involves pushing the fetal head back in with performing a cesarean section. or internal cephalic replacement followed by Cesarean section
- intentional clavicular fracture, which reduces the diameter of the shoulder girdle that requires to pass through the birth canal.
- symphysiotomy
Symphysiotomy is a surgical procedure in which the cartilage of the symphysis pubis is divided to widen the pelvis allowing childbirth when there is a mechanical problem.- Introduction :...
, which makes the opening of the birth canal laxer by breaking the connective tissue between the two pubesThe android pubic bone is the ventral and anterior of the three principal bones composing either half of the pelvis.It is covered by a layer of fat, which is covered by the mons pubis.It is divisible into a body, a superior ramus and an inferior ramus....
bones facilitating the passage of the shoulders.
- abdominal rescue, described by O'Shaughnessy, where a hysterotomy
A hysterotomy is an incision in the uterus, commonly combined with a laparotomy during a caesarean section. Hysterotomies are also performed during fetal surgery.- See also :* Hysterotomy abortion* Hysterectomy...
facilitates vaginal delivery of the impacted shoulder
Management
Management of shoulder dystocia has become a focus point for many obstetrical nursing units in North America. Courses such as the Canadian
More-OB program encourage nursing units to do routine drills to prevent delays in delivery which adversely affect both mother and fetus. A common treatment algorithm is ALARMER
- A sk for help. This involves requesting the help of an obstetrician, anesthesia and pediatrics for subsequent resuscitation of the infant.
- L eg hyperflexion (McRoberts' maneuver)
- A nterior shoulder disimpaction (suprapubic pressure)
- R ubin maneuver
- M anual delivery of posterior arm
- E pisiotomy
- R oll over on all fours
The advantage of proceeding in the order of ALARMER is that it goes from least to most invasive, thereby reducing harm to the mother in the event that the infant delivers with one of the earlier maneuvers. Unfortunately, the most effective maneuver, the Gaskin Maneuver, is considered last by those practicing under the medical model, because it interferes with the positioning of the woman with legs up in the stirrups for the convenience of the physicians. How unfortunate it is that the simple rolling over of the mother onto all fours would be considered only after a physician has performed more invasive maneuvers. In the event that these maneuvers are unsuccessful, a skilled obstetrician may attempt some of the additional procedures listed below. Intentional clavicular fracture is a final attempt at nonoperative vaginal delivery prior to Zavanelli's maneuver or symphisiotomy, both of which are considered extraordinary treatment measures.
Risk factors
Although the definition is imprecise, it occurs in approximately 1% of vaginal births. There are well-recognised risk factors, such as diabetes, fetal macrosomia, and
maternal obesity-What is considered obese?:Nearly two-thirds of Americans are considered overweight and one in three are obese, meaning they have a body mass index of 30 or greater...
, but it is often difficult to predict. Despite appropriate obstetric management, fetal injury (such as brachial plexus injury) or even fetal death can be a complication of this obstetric emergency.
Recurrence rates are relatively high and low most of the short time.
Complications
The major concern of shoulder dystocia is damage to the upper
brachial plexusThe brachial plexus is an arrangement of nerve fibers, running from the spine, formed by the ventral rami of the lower cervical and upper thoracic nerve root, specifically from below the fifth cervical vertebra to above the first thoracic vertebra...
nerves. These supply the sensory and motor components of the shoulder, arm and hands. The aetiology of injury to the foetus is debated, but a probable mechanism is manual stretching of the nerves, which in itself can cause injury. Furthermore, excess tension may physically tear the nerve roots out from the neonatal spinal column, resulting in total dysfunction. The ventral roots (motor pathway) are most prone to injury, as they are in the plane of greatest tension (anterior, sensory nerves are somewhat protected due to the usual inward movement of the shoulder).
- Klumpke paralysis
Named named after Augusta Déjerine-Klumpke, Klumpke's paralysis is a variety of partial palsy of the lower roots of the brachial plexus. The brachial plexus is a network of spinal nerves that originates in the back of the neck, extends through the axilla , and gives rise to nerves to the upper...
- Erb's Palsy
Erb's Palsy is a paralysis of the arm caused by injury to the upper group of the arm's main nerves, specifically, spinal roots C5-C7. These form part of the brachial plexus, comprising the ventral rami of spinal nerves C5-C8, and T1. These injuries arise most commonly, but not exclusively, from...
- Foetal hypoxia
- Foetal death
- Cerebral palsy
- Maternal post partum haemorrhage
Obstetrical hemorrhage refers to heavy bleeding during pregnancy, labor, or the puerperium. Bleeding may be vaginal and external, or, less commonly but more dangerously, internal, into the abdominal cavity...