EM@3AM: Ovarian Torsion

Author: Rachel Bridwell, MD (@rebridwell, EM Resident Physician, San Antonio, TX) // Edited by: Brit Long, MD (@long_brit, EM Attending Physician, San Antonio, TX) and Alex Koyfman, MD (@EMHighAK, EM Attending Physician, UTSW / Parkland Memorial Hospital)

Welcome to EM@3AM, an emDOCs series designed to foster your working knowledge by providing an expedited review of clinical basics. We’ll keep it short, while you keep that EM brain sharp.

A 30-year-old female presents to the ED with right lower quadrant and flank pain that started 6 hours ago. The patient reports sudden onset pain that is progressively worsening, refractory to ibuprofen. She denies fevers, rigors, or dysuria, but endorses constant nausea and non-bloody, non-bilious emesis. Review of systems is unremarkable. Vital signs include BP 125/60, HR 107, T 100.2 oral, RR 15, SpO2 98% on room air.

Pertinent physical examination findings:
General: Alert and oriented x 3, though visibly uncomfortable
CV and lungs: Tachycardic, otherwise normal
Abdomen: Tender in RLQ, +rebounding, +guarding. No CVA tenderness //  Pelvic: Significant tenderness along right adnexa

What’s the next step in your evaluation and treatment?

Answer: Ovarian torsion1-18

Definition: Partial or complete rotation of ovary on ligamentous support within the abdomen/pelvis.



  • Most affected females are of reproductive age, most often associated with a cyst/mass
    • Right ovary more likely to twist; thought to be due to longer utero-ovarian ligament on the right and the sigmoid colon on left1
  • Tumor considerations: More likely to occur in benign tumor vs malignant, which occurs <2%2,6,7
    • 10 year retrospective review: cysts 51.9%, benign tumors 30.8%6
  • Size: Cysts 4-5 cm increase risk, though torsion has been documented for cysts <5 cm, ranging 1-30 cm1
    • Incidence of torsion decreases once mass is of significant size due to decreased maneuverability
  • 25% have no previously known pelvic pathology
  • Pediatric considerations:
    • 15% of torsions occur in pediatric patients
    • Average age of torsion in girls is 10 years old, with >50% of patients less than 15 years old presenting with torsion with normal ovaries2,3
  • Pregnancy considerations
    • 10-22% of torsion occurs in pregnancy, with increased risk at 10-17 weeks of gestation with >4 cm mass4,5
    • Those undergoing reproductive/infertility evaluation and treatment are at higher risk
  • 15% of cases occur in patients post menopause


Anatomy—Curse and blessing of double blood supply

  • Ovary encased in ligaments (infundibulopelvic and utero-ovarian ligaments) with a blood supply for each pole of ovary8
  • These ligaments are not fixed: Length of the infundibulopelvic ligament varies with age and shortens as women grow older
  • Once the ovary torses, blood flow decreases, starting with decreased venous outflow, followed by arterial compression. This can lead to tissue necrosis, and peritonitis may develop.
  • Superior and lateral blood supply—ovarian artery takes off from aorta8
  • Medial and inferior blood supply—uterine artery takes off from internal iliac artery
    • Even if torsion cuts off ovarian artery blood supply, uterine artery can provide doppler flow that is detectable8,9


Clinical Presentation:

  • Signs and symptoms
    • Unilateral pelvic pain in a female is torsion until proven otherwise
    • Tachycardia may be seen secondary to pain
    • Symptom presentation: stabbing pain 70%, nausea/vomiting 70%, sudden sharp in lower abdomen in 60%, pain radiates to back/flank/groin 51%, fever < 2%, peritoneal signs 30%1
    • Up to 30% of patients have no pain!
    • Differential: appendicitis, diverticulitis, PID/TOA, cervicitis, renal colic, nephrolithiasis, hemorrhagic ovarian cyst, bowel obstruction, ectopic pregnancy, mesenteric adenitis, ovarian hyperstimulation syndrome



  • Assess ABCs
    • Low grade fever may be present; late stage may have hypotension and tachycardia due to tissue necrosis10
  • Perform a complete physical examination. However, normal exam cannot exclude torsion!
    • Abdomen: May have tenderness in right or left lower quadrant
    • Pelvic:  May detect mass and/or pain along adnexa. However, sensitivity of pelvic exam for adnexal/ovarian mass is poor (ranging from 15-36%). Do not perform in premenarchal girls.
    • Up to 30% have no abdominal or pelvic tenderness on exam
  • Imaging:
    • US with Doppler studies is often preferred
      • TVUS: adult females
      • TAUS: pediatric with FULL bladder (sonographic window)
      • 50% ovarian torsion cases in children involve cysts
    • 1/3 cases of known ovarian torsion have normal Doppler flow on US
    • Most common finding: enlarged heterogeneous ovary9
      • Other findings: enlarged hyper or hypoechoic ovary secondary to generalized edema, peripherally displaced follicles with hyperechoic central stroma “string of pearls” sign, midline ovary, free fluid in pelvis10
      • Doppler: little or no venous flow (first to get cut off), absent arterial flow (less common, but diagnostic), no diastolic flow or reversed flow11
      • Focal tenderness with flow—does not exclude or diagnose torsion but shows vascular viability of ovary10
      • Whirlpool sign—shown to increase true positive rate of diagnosis11
      • Ultrasound in 41 cases of confirmed torsion, ovarian volume of affected ovary was 12x size of normal contralateral ovary9
    • CT: Common features seen on CT are enlarged ovary, uterine deviation towards torsion, smooth wall thickening of cystic mass, ascites, fallopian tube thickening10
      • In a case-control series of US vs CT in females presenting with torsion:
        • US: sensitivity 80% (58.4-91.9%) and specificity 95% (64%-99.1%)
        • CT: sensitivity 95% (69.9%-100.0%) and specificity 87.5% (64.0%-97.2%)13
      • MRI can be used if US equivocal14
        • Radiation sparing and provides soft tissue visualization of mass though not expedient4
      • Laboratory evaluation:
        • Not necessary for diagnosis, though HCG is important to obtain as it affects evaluation and differential diagnosis
        • HCG, CBC, CMP, UA
          • Leukocytosis associated with prompt surgical intervention; though cannot be relied on to rule in or out condition7
        • CA-125 may suggest ovarian malignancy4
        • IL-6 elevated in torsion, though not useful emergently15,16
          • Serum IL-6> 10.1 pg/mL had 16x increased risk of torsion16



  • Pain control, antiemetics, and IVF rehydration
  • Consult gynecology for emergent diagnostic laparoscopy and detorsion4
    • Goal is preservation of function and prevention of complications
    • Antibiotics recommended if sepsis present
    • Good outcomes up to 36 hours after onset in pediatric patients3
    • More recent evidence steering away from oophoropexy at the time of laparoscopy, may defer to later date or forgo17,18
    • In post-menopausal women, bilateral oophorectomy is recommend17
    • Intermittent torsion can occur and result in negative or inconclusive imaging. In patients with concerning presentation for torsion, discuss the case with OBGYN.



  • Emergent Gynecology consult for definitive surgical management
  • Consider in female patients with back, abdominal, or flank pain
  • 70% present without peritoneal signs, 30% present without pain1
  • Ovarian salvage time up to 36 hours3

A 27-year-old woman presents with acute onset of right pelvic pain and nausea that started six hours ago. She reports two prior episodes that were similar, but symptoms with those episodes resolved within one hour. On examination, she appears uncomfortable and is mildly tachycardic. She has tenderness to palpation of the right adnexa. A transvaginal ultrasound is ordered. What is the most common ultrasound finding in ovarian torsion?

A) Complete arterial obstruction

B) Heterogeneous appearance of the ovarian stroma

C) Ovarian enlargement

D) Whirlpool sign



Answer: C

Ovarian torsion is a gynecological emergency and is caused by the twisting of the ovary and fallopian tube on the vascular pedicle. While it can rarely occur with a normal ovary, the majority of cases are associated with some type of ovarian pathology (e.g., tumor, cyst, hyperstimulation syndrome secondary to infertility treatments). Patients present with acute onset of unilateral pelvic pain often accompanied by nausea and vomiting. They may relate previous episodes of similar pain due to intermittent torsion. Ultrasound is the test of choice for diagnosing ovarian torsion. The most common finding is ovarian enlargement due to venous and lymphatic engorgement. Complete arterial obstruction is unlikely due to the dual blood supply to the ovary from both the uterine and ovarian arteries. Therefore, in cases of high clinical suspicion, the finding of arterial flow does not eliminate the possibility of torsion. Gynecology consultation is warranted for all cases of confirmed or suspected ovarian torsion.

As noted above, complete arterial obstruction (A) is unlikely due to the dual blood supply to the ovary. Over half of surgically-proven ovarian torsion will have documented arterial flow on Doppler ultrasound. Heterogeneous appearance of the ovarian stroma (B) secondary to edema is a classic finding of torsion but is often absent, especially in cases of prolonged symptoms. The presence of the whirlpool sign (D), or coiled vessels, is nearly 90% accurate in diagnosing torsion, but it is not the most common finding on ultrasound.

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References/Further Reading:

  1. Houry D, Abbott JT. Ovarian torsion: A fifteen-year review. Ann Emerg Med. 2001;38(2):156-159. doi:10.1067/mem.2001.114303
  2. Tsafrir Z, Azem F, Hasson J, et al. Risk Factors, Symptoms, and Treatment of Ovarian Torsion in Children: The Twelve-Year Experience of One Center. J Minim Invasive Gynecol. 2012;19(1):29-33. doi:10.1016/j.jmig.2011.08.722
  3. Anders JF, Powell EC. Urgency of Evaluation and Outcome of Acute Ovarian Torsion in Pediatric Patients. Arch Pediatr Adolesc Med. 2005;159(6):532. doi:10.1001/archpedi.159.6.532
  4. Huang C, Hong M-K, Ding D-C. A review of ovary torsion. Tzu-chi Med J. 2017;29(3):143-147. doi:10.4103/tcmj.tcmj_55_17
  5. Yen C-F, Lin S-L, Murk W, et al. Risk analysis of torsion and malignancy for adnexal masses during pregnancy. Fertil Steril. 2009;91(5):1895-1902. doi:10.1016/j.fertnstert.2008.02.014
  6. White M, Stella J. Ovarian torsion: 10-year perspective. Emerg Med Australas. 2005;17(3):231-237. doi:10.1111/j.1742-6723.2005.00728.x
  7. Oltmann SC, Fischer A, Barber R, Huang R, Hicks B, Garcia N. Cannot exclude torsion—a 15-year review. J Pediatr Surg. 2009;44(6):1212-1217. doi:10.1016/j.jpedsurg.2009.02.028
  8. Standring S. Gray’s Anatomy : The Anatomical Basis of Clinical Practice.
  9. Servaes S, Zurakowski D, Laufer MR, Feins N, Chow JS. Sonographic findings of ovarian torsion in children. Pediatr Radiol. 2007;37(5):446-451. doi:10.1007/s00247-007-0429-x
  10. Chang HC, Bhatt S, Dogra VS. Pearls and Pitfalls in Diagnosis of Ovarian Torsion. RadioGraphics. 2008;28(5):1355-1368. doi:10.1148/rg.285075130
  11. Valsky D V., Esh-Broder E, Cohen SM, Lipschuetz M, Yagel S. Added value of the gray-scale whirlpool sign in the diagnosis of adnexal torsion. Ultrasound Obstet Gynecol. 2010;36(5):630-634. doi:10.1002/uog.7732
  12. Graif M, Itzchak Y. Sonographic evaluation of ovarian torsion in childhood and adolescence. Am J Roentgenol. 1988;150(3):647-649. doi:10.2214/ajr.150.3.647
  13. Swenson DW, Lourenco AP, Beaudoin FL, Grand DJ, Killelea AG, McGregor AJ. Ovarian torsion: Case-control study comparing the sensitivity and specificity of ultrasonography and computed tomography for diagnosis in the emergency department. Eur J Radiol. 2014;83(4):733-738. doi:10.1016/j.ejrad.2014.01.001
  14. Abeş M, Sarihan H. Oophoropexy in children with ovarian torsion. Eur J Pediatr Surg. 2004;14(3):168-171. doi:10.1055/s-2004-817887
  15. Cohen SB, Wattiez A, Stockheim D, et al. The accuracy of serum interleukin-6 and tumour necrosis factor as markers for ovarian torsion. Hum Reprod. 2001;16(10):2195-2197. http://www.ncbi.nlm.nih.gov/pubmed/11574515. Accessed February 15, 2019.
  16. Daponte A, Pournaras S, Hadjichristodoulou C, et al. Novel serum inflammatory markers in patients with adnexal mass who had surgery for ovarian torsion. Fertil Steril. 2006;85(5):1469-1472. doi:10.1016/j.fertnstert.2005.10.056
  17. Oelsner G, Shashar D. Adnexal torsion. Clin Obstet Gynecol. 2006;49(3):459-463. http://www.ncbi.nlm.nih.gov/pubmed/16885653. Accessed February 15, 2019.
  18. Breech LL, Hillard PJA. Adnexal torsion in pediatric and adolescent girls. Curr Opin Obstet Gynecol. 2005;17(5):483-489. http://www.ncbi.nlm.nih.gov/pubmed/16141762. Accessed February 15, 2019.

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