Synovial cysts of the hip

Abstract

Background: Synovial cysts of the hip are relatively rare lesions comparing to other joints. Patients are usually asymptomatic, but in some cases symptoms such as pain and/or compression of vessels or nerve could be present. Purpose of the study was to define clinical features and optimal management of synovial cyst of the hip joint through an accurate review of the literature.

Methods: We present three consecutive cases treated with three different therapeutic strategies: surgical excision, wait-and-see and needle aspiration. An accurate review of the literature has been performed to identify patients who had been treated for synovial cyst of the hip.

Results: Due to the rarity of the disease, there are no significant data in literature supporting the gold standard of treatment. Treatment of the synovial cyst depends on their size, symptoms and comorbidities.

Conclusions: Most of the Authors recommend surgical treatment for symptomatic synovial cysts and needle aspiration as an option treatment in asymptomatic patients without vessel or nerve compression. In patients that referred symptoms in correspondence with the hip joint, not strictly related with radiograph findings, a CT or MRI examinations should be performed to exclude possible differential diagnosis.

Keywords: benign, arthritis, joint, ganglion cyst, iliopsoas bursitis.

Figure 1

Case 1. Magnetic resonance imaging (MRI) examination findings. A,B) Axial T1-weighted images showed low-intensity area, in front of the right hip joint (asterisk). It appears as a soft cystic lesion near the vascular bundle (white arrow). A communication with joint capsule is clearly identifiable (small white arrows). C) Tridimensional reconstruction has been performed to evaluate preoperatively the relations between cystic lesion (asterisk) and vascular bundle (white arrow)

Figure 2

Case 1. Intraoperative phases of surgical removal of the synovial cyst. A) patient in supine position. The longitudinal surgical approach has been drawn on the cutis. B) Surgical isolation of the femoral artery (white arrow) that appeared dislocated superficially. C) Surgical isolation of the femoral nerve (white head-arrow) that also appeared to be compressed by the mass. D) The synovial cyst (asterisk) has been detected deeper to femoral nerve and femoral vessels. E) Marginal excision of the synovial cyst through the cystic wall up to the joint capsule. F) Surgical field after excision of the synovial cyst

Figure 3

Case 2. Magnetic resonance imaging (MRI) examination findings. A,B) Coronal short tau inversion-recovery (STIR) image showing the full extent of a large synovial cyst arising from the right hip joints (asterisk). C) Sagittal T2-weighted MRI shows the extension of the cyst (asterisk) in the anterior part of the hip joint. D) Axial T2-weighted MRI shows the communication (small white arrows) between the cyst (asterisk) and the hip joint. The femoral vessels (white arrow) appear to be compressed and dislocated by the cyst, as evident comparing with the contralateral side