A 56-year-old male patient presented to the emergency department with intermittent claudication for the past 6 weeks after a work accident and hip joint trauma. He had no risk factors for atherosclerosis and upon examination there was no signs of peripheral vascular disease.
A computed tomography (CT) of the hips was undertaken which demonstrated a cystic lesion, anterior to the right common femoral artery (CFA) and vein (CFV) (Fig. 1).
To further assess the lesion, magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) of the hips was undertaken and demonstrated a fluid-filled cyst which originated from the right hip labrum and caused indentation of the right CFA on the MRA (Fig. 2).
After discussion with the patient, non-surgical treatment with CT guided aspiration was decided as the option of choice to relieve the patient of his symptoms (Fig. 3). However, ultrasound-guided aspiration of the cyst is another and possibly a better option than CT with the benefit of real-time and Doppler imaging.
The majority of vasculogenic intermittent claudication is due to endoluminal atherosclerosis with typical cardiovascular risk factors. Intermittent claudication in the absence of such factors should point towards a few uncommon but important causes of claudication that should be promptly diagnosed [1]. Some uncommon causes include vasculitis, cystic adventitial disease, popliteal entrapment syndrome, fibromuscular dysplasia and endofibrosis of the iliac artery [1, 2].
Paralabral cysts in the hip are rare and can be asymptomatic or associated with trauma, capsular laxity, degenerative disease and hip arthroplasty [3, 4]. It is even rarer for them to cause nerve or vascular compression. Select cases of paralabral cysts causing CFV [5] and sciatic nerve compression [6] have been described.
Cystic lesions that occur near the joint are classified as either ganglionic or synovial cysts and cannot be distinguished on MRI. Thus, acetabular paralabral cysts are named due to their proximity to the acetabular labrum.
Paralabral cysts associated with labral tears generally do not regress without intervention and can often grow over time leading to increased risk of neurovascular compression. Arthroscopic debridement or surgical excision of the cysts are the treatment of choice [5, 7, 8]. In this case, MRI for assessment of a labral tear was not performed but is very important for complete assessment and guiding management.
Peripheral venous [5], arterial [9] and nerve [6, 8, 9] compression due to paralabral cysts has been described. Bystrom et al have described the only case of CFA and CFV compression due to a paralabral cyst before. The exact pathophysiology is not clear but speculations are that loss of congruity between femoral head and acetabulum lead to increased intra-articular pressure which forces synovial fluid through the labral tear and forms a cyst [4, 7]. Non-operative treatment options for peri-articular ganglion cysts and paralabral cysts include image-guided aspiration, however, with recurrence rates of up to 44% [8].
Generally in the shoulder and knee, arthroscopic debridement and cyst evacuation results in much lower recurrence rates and resolution of neurovascular compression [8].
In this case, the patient opted for non-surgical management with CT-guided cyst evacuation and decompression of the arterial impingement. The patient was subsequently followed-up 4 weeks later with complete recovery from the hip pain and claudication symptoms.
CFA compression from acetabular paralabral cyst
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Based on the patient’s CT and MRI images, the following main features are observed:
Based on imaging findings and clinical presentation, potential diagnoses include:
Given the patient’s history of trauma, localized symptoms, and imaging demonstration of a periarticular hip cyst compressing the vessels, a paralabral cyst of the hip is highly likely.
Taking into account the patient’s age, symptoms (intermittent claudication after trauma), clear radiographic evidence of a periarticular cyst in the hip region compressing the femoral artery (or external iliac artery), and the differential from other conditions, the most likely diagnosis in this case is:
“Hip Paralabral Cyst causing Femoral Artery Compression, leading to Intermittent Claudication.”
Based on the final diagnosis of this case, the following treatment and rehabilitation strategies can be considered:
Disclaimer: This report is based on the provided medical history and imaging data for reference and does not replace in-person consultation and professional medical advice. If you have any questions or notice any changes in your symptoms, please consult a specialized physician promptly.
CFA compression from acetabular paralabral cyst
