What is Positive Obturator Sign – Acute Appendicitis

What is Positive Obturator Sign – Acute Appendicitis

Acute appendicitis refers to acute inflammation of the appendix, typically due to an obstruction of the appendiceal lumen. In both children and adults, it is the most common cause of acute abdomen requiring emergency surgical intervention.

The characteristic features of acute appendicitis are:

  • Periumbilical abdominal pain that migrates to the right lower quadrant (RLQ)
  • Anorexia (loss of appetite)
    • Hamburger sign: If there is no loss of appetite, appendicitis is unlikely.
  • Nausea
  • Fever
  • RLQ abdominal tenderness.

What is Positive Obturator Sign – Acute Appendicitis

Clinical signs of appendicitis

  • McBurney point tenderness (RLQ tenderness)
    • Tenderness at the junction of the lateral third and medial two-thirds of a line drawn from the right anterior superior iliac spine to the umbilicus
    • This point corresponds to the location of the base of the appendix.
  • RLQ guarding and/or rigidity
  • Rebound tenderness (Blumberg sign), especially in the RLQ
  • Rovsing’s sign: RLQ pain elicited on deep palpation of the LLQ
  • Psoas sign
    • Can be elicited on flexing the right hip against resistance
    • RLQ pain may be elicited on passive extension of the right hip
  • Obturator sign: RLQ pain on passive internal rotation of the right hip with the hip and knee flexed
  • Hyperesthesia within Sherren triangle: formed by the anterior superior iliac spine, umbilicus, and symphysis pubis
  • Lanz point tenderness: at the junction of the right third and left two-thirds of a line connecting both the anterior superior iliac spines
  • Pain in the Pouch of Douglas: pain elicited by palpating the rectouterine pouch on rectal examination
  • Baldwin sign: pain in the flank when flexing the right hip (suggests an inflamed retrocecal appendix)

What is Positive Obturator Sign – Acute Appendicitis


Laboratory testing:

Although limited in their ability to differentiate appendicitis from other causes of abdominal pain, the following studies are typically obtained in children suspected to have appendicitis:

  • White blood cell count (WBC): Will be elevated
  • Differential with calculation of the absolute neutrophil count (ANC): Will be elevated
  • C-reactive protein (CRP): Will be elevated
  • Urinalysis: mild pyuria may be present. Also to rule out urinary tract infection

Imaging studies:

  • Abdominal ultrasonography: is inexpensive, safe, and widely available. Diagnostic accuracy, reported to range from 71 to 97% and is highly dependent on operator skill. Ultrasonography is especially useful in women who are pregnant or of childbearing age, and in children. Major advantages to ultrasonography include non-invasiveness, short acquisition time, lack of radiation exposure, and potential for discovering other causes of abdominal pain (e.g., ovarian cysts, ectopic pregnancy, tubo-ovarian abscess).
  • Abdominal CT with IV contrast: is more precise than ultrasonography and more reproducible from hospital to hospital. It has a diagnostic accuracy rate for acute appendicitis of 93 to 98%.

What is Positive Obturator Sign – Acute Appendicitis


Conservative management, which includes bowel rest, antibiotics, and analgesics, is indicated in patients with an inflammatory appendiceal mass (phlegmon) or an appendiceal abscess because surgical intervention is associated with a higher risk of complications in these patient groups.

The current standard of management of acute appendicitis is emergency appendectomy (open or laparoscopic) and broad-spectrum antibiotics.

Interval appendectomy 6–12 weeks after resolution of the acute episode can be performed in these patients to prevent a recurrence.

Positive Rovsing’s Sign

How to look for Obturator Sign

The obturator sign is an indicator of irritation to the obturator internus muscle.

  • The technique for detecting the obturator sign, called the obturator test, is carried out on each leg in succession.
  • The patient lies on her/his back with the hip and knee both flexed at ninety degrees.
  • The examiner holds the patient’s ankle with one hand and knee with the other hand.
  • The examiner rotates the hip by moving the patient’s ankle away from the patient’s body while allowing the knee to move only inward. This is flexion and internal rotation of the hip.

The principles of the obturator sign in the diagnosis of appendicitis are similar to that of the psoas sign. The appendix is commonly located in the retrocecal or pelvic region. The obturator sign indicates the presence of an inflamed pelvic appendix.

What is Positive Obturator Sign - Acute Appendicitis - www.DailyMedEd.com

The obturator sign. Pain on passive internal rotation of the flexed thigh. Examiner moves lower leg laterally while applying resistance to the lateral side of the knee (asterisk), resulting in internal rotation of the femur.

What is Positive Obturator Sign – Acute Appendicitis


This video on Obturator sign has been provided by: MDforALL
What is Positive Obturator Sign – Acute Appendicitis

Other physical examinations that helps in diagnosing acute appendicitis are Psoas sign and Rovsing’s sign.

What is Positive Obturator Sign - Acute Appendicitis - DailyMedEd.com
Click on the button below for more Physical Examination Video Tutorials. Also, take advantage of many more FREE medical video tutorials.


Click on the Image below if you are having trouble with your Time Management:

Click on the Image below to view

USMLE Step 2 CS Mnemonics:

0 0 votes
Article Rating
Notify of

Inline Feedbacks
View all comments