11. Case of the month: Right hip pain

Images Daniel Loui  Text Genevieve Carbonatto

A 60 year old lady presents with recurrent syncopes associated with frequent falls.

2 weeks prior to presentation she had a fall on her right buttock  causing  right hip pain. Subsequently she developed a small heamatoma over her right buttock and a larger right thigh haematoma. She presents with  severe pain on flexion of her right hip. Lying flat in bed also elicits severe right hip pain in her right inguinal area.

She states she is on  warfarin for a metallic valve as a consequence of infective endocarditis several years ago requiring a valve replacement.

Because of her pain she had been taking paracetamol. When she takes paracetamol she increases her warfarin because she says paracetamol  causes her INR to drop. She increased her warfarin from 4 mg to 6 mg.

Since her fall 2 weeks ago she is having increasing presyncopal episodes and has now presented after another fall.

On examination she has no bony tenderness or deformity to her right thigh. There is a large medial thigh haematoma with a small yellowing bruise  above her right buttock.

On examination she is able to flex her right hip to 30 degrees but no more due to pain. She is unable to lie completely flat in bed. She can lie back to 45 degrees.

An Xray of her pelvis and right hip and femur shows no fracture.

A point of care ultrasound is performed to look for free fluid in the abdomen.

There is no fluid in the right and left upper quadrants or in the pelvis.

This is her scan over the area of pain

This is the image with colour Doppler

How would you describe these clips?

Whenever you are not quite sure at what you are looking at it is best to simply just  describe what you see.

Here there is an area of mixed echogenicity.   There is no movement in this area.  There is no blood  flow within the area of mixed echogenicity.

This could be either an abscess or a haematoma. It is not muscle (the structure is not organised). It is not bowel (it doesn’t move). It is in the area of the psoas muscle. It is either part of the psoas or in the retroperitoneal space.

On the basis of the scan a CT scan is ordered which shows a  large psoas haematoma with a smaller volume in the retroperitoneal space.

What structures lie in the retroperitoneal space and how is the retroperitoneal space divided ?

The retroperitoneal space lies between the parietal peritoneum and the transversalis fascia. It is divided into 3 compartments seperated by fascia between which communication is possible between the spaces and peritoneum and the pelvis according to the theory of interfascial spread (1) . The fascial planes however greatly limit the spread of retroperitoneal collections such as haematomas and abcesses. The retroperitoneum contains the adrenals, the kidneys and ureters, the ascending and descending colon, the caecum , the duodenal loop,  the pancreas and the great vessels and their branches.

It is divided into 3 compartments

  • the anterior pararenal space
  • the perirenal space
  • the posterior pararenal space

Is the EFAST exam good at detecting retroperitoneal haemotomas?

The EFAST exam is insensitive in detecting retroperitoneal haematomas including pelvic haematomas from a fractured pelvis for example.

In trauma, with a negative EFAST exam in a hypootensive patient it is important to consider retroperitoneal bleeding.

It is possible to have some  communication between the retroperitoneum and the peritoneal cavity but the amount of free fluid will not explain the clinical signs.

CT is the best modality to look for injury in the retroepritoneum. Note that in this case, there was no free fluid in the peritoneal cavity but a large haematoma visible on ultrasound.

Her haemoglobin comes back as 80. Her INR  at > 10.  The haematoma explains the pain on hip flexion and the difficulty in being able to lie flat with the leg fully extended.

She is given 3mg of Vit K , her warfarin is withheld and she is admitted.

 

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