-VISIT OUR OTHER FORUMS- OB-GYN-L Ultrasound Ultrasound History Fibroid Forum Physicians-in-Training Tech Talk OBSTET-L (portuguese) OBGIN-L (spanish) Nursing

Re: episiotomy and shoulder dystocia From: Jason Gardosi (jason.gardosi@nottingham.ac.uk) Thu May 1 06:14:38 1997 Messages sorted by: [ date ][ thread ][ subject ][ author ] Next message: Theresa333@aol.com: "perceptions of "old"" Previous message: paul297@juno.com: "Medicaid OB" Next in thread: Harvey S. Marchbein, M.D.: "Re: episiotomy and shoulder dystocia" Reply: Harvey S. Marchbein, M.D.: "Re: episiotomy and shoulder dystocia" At 22:59 30/04/97 -0500, you wrote: >What I don't quite get the grasp of is your "on >hands and knees" positon for the paatient with shoulder dystocia. As >much as I try, and I have tried (and even discussed it with my >partners), I can't envision that position giving more room for a >shoulder dystocia since every response to the list has stated that it is >a bony dystocia, not a soft tissue problem. I'm having trouble >understanding the mechanics behind a change in the mother's positon and >a change in the orientation/size of the bony pelvis which is restricting >the delivery of the infant's shoulders. Harvey - The anterio-posterior diameter is reduced in recumbent and lithotomy positions where the weight is taken on the sacrum. The sacrum is capable of rotational movement through an axis at the upper part of the sacro-iliac joint, about 5 cm below the sacral promontory (Weisl H: Acta Anat 1955;23:80-91). This movement results in an increase in the AP diameter of between 10 and 20 mm (Borrell V and Fernstrom I, Acta Obstet Gynec Scand 1957;36:42-57 and Acta Radiol 1957;47:365-70). As the sacrum is wedge-shaped in cross section, backwards movement will splay the iliac bones so that the transverse diameter also increases, as shown by JGB Russel's XRay studies (J Obstet Gynaecol Br Cmwlth 1969;76:817-20; Br J Obstet Gynecol 1982;89:712-5). In a vaginal ultrasound study published as part of my thesis, I have also found that upright positions increase the bispinous diameter (average 4mm). I think the first and best maneuvre in any suspected SD is to get the mother squatting or kneeling. Many good midwives already do this, before (and usually instead of) hitting the panic button. Jason -- ************************************************* Jason Gardosi MD FRCS MRCOG PRAM (Perinatal Research, Audit & Monitoring) Queen's Medical Centre, Nottingham NG7 2UH, U.K. Tel +44 115 9709211 Fax +44 115 9709791 http://www.nottingham.ac.uk/~mgzobgyn/PRAM/ Next message: Theresa333@aol.com: "perceptions of "old"" Previous message: paul297@juno.com: "Medicaid OB" Next in thread: Harvey S. Marchbein, M.D.: "Re: episiotomy and shoulder dystocia" Reply: Harvey S. Marchbein, M.D.: "Re: episiotomy and shoulder dystocia"

Return to

Mail a New Message to the Forum: ob-gyn-l@obgyn.net Forum Administrator: geffrey.klein@obgyn.net Report Technical Problems: webmaster@obgyn.net Last Updated: Mon Nov 2 05:21:59 2009

The American Medical Association is no longer designating CME hours for AMA Category II CME credit. However, physicians themselves may self designate learning activities as Category II CME credit hours if they feel it is of sufficient educational merit and meets the formal definitions of continuing medical education. OBGYN.net believes these interaction in this forum meets these criteria. For further information see the AMA web site.