Interesting case today, gentleman coming in w/ months of LLQ pain and intermittent diarrhea and a history of hip fx after a fall. On imaging he was noted to have pan colitis and a psoas abscess, which raised the question: could a bout of diverticulitis have led to the psoas absces itself?`
Retroperitoneal fistulas are a known complication of IBD. ANd there are case reports (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3669818/) of presentations of what would appear to be true articular hip pain that is actually a psoas abscess. So, keep it in mind as a mimicker of MSK hip pain especially in a patient with h/o IBD or suspicion of diverticulitis.
Couple of cool MSK imaging points from the case as well:
Acetabular protrusio: protrusion of the femoral head into the pelvis, usually caused by OA but can be idiopathic and more common in women, usually presenting as pain in younger ages. Secondary usually from OA, RA, post-THA complications (our patient), can also be seen in Marfan/Ehler Danlos.