Mert Murat, Oztürkmen Yusuf, Unkar Ethem Ayhan, Erdoğan Sinan, Uzümcügil Onat
Department of Orthopaedics and Traumatology, H.M. Istanbul Education and Research Hospital, İstanbul, Turkey.
Int J Surg Case Rep. 2013;4(10):805-8. doi: 10.1016/j.ijscr.2013.07.008. Epub 2013 Jul 29.
Polyethylene (PE) wear debris after total hip arthroplasty (THA) may cause formation of a soft tissue mass due to inflammatory reaction. To the best of our knowledge we report the first case in whom the diagnosis was made after examination of the hip, pelvis and lumbar spine with detailed radiological methods and the plain radiographs showed no signs of loosening of the THA.
We report a 52 years-old woman who presented with a cyst causing sciatic irritation in her gluteal region due to wear debris after THA. Magnetic resonance imaging (MRI) was useful in detecting the cyst. Resolution of the cyst occured after subtotal cystectomy and revision of the acetabular components.
Although plain radiographs can show signs of the underlying pathology; such as osteolysis, loosening of the components and wear of the PE liner, they are unable to detect cystic lesions. Cystic lesions may be an early sign of wear debris.
This case shows us that sciatic neuropathy with no evidence of nerve root impingement on lumbar MRI in a patient with THA requires also examination of the hip and pelvis with detailed radiological methods, such as MRI, in addition to plain radiography. Removal of the source of debris via revision surgery following subtotal cystectomy leads to the resolution of the remaining portion of the cyst and also relief of the symptoms of sciatic nerve compression.
全髋关节置换术（THA）后聚乙烯（PE）磨损碎屑可能因炎症反应导致软组织肿块形成。据我们所知，我们报告了首例通过详细的放射学方法对髋部、骨盆和腰椎进行检查后确诊的病例，而普通X线片未显示THA松动迹象。
我们报告一名52岁女性，因THA后磨损碎屑在其臀区出现囊肿并引起坐骨神经刺激症状。磁共振成像（MRI）有助于检测囊肿。囊肿在次全囊肿切除和髋臼组件翻修后消退。
尽管普通X线片可显示潜在病理变化的迹象，如骨质溶解、组件松动和PE内衬磨损，但它们无法检测出囊性病变。囊性病变可能是磨损碎屑的早期迹象。
该病例表明，对于THA患者，若腰椎MRI无神经根受压证据但出现坐骨神经病变，除普通X线摄影外，还需用MRI等详细放射学方法对髋部和骨盆进行检查。次全囊肿切除后通过翻修手术清除碎屑来源可使囊肿其余部分消退，并缓解坐骨神经受压症状。
