Gonzalez Peter, Pepper Michelle, Sullivan William, Akuthota Venu
University of Colorado School of Medicine, Aurora, CO 80045, USA.
Pain Physician. 2008 May-Jun;11(3):327-31.
Of patients presenting to pain clinics, complaints are of low back or buttock pain with or without radicular leg symptoms is one of the most common. Piriformis syndrome may be a contributor in up to 8% of these patients. The mainstay of treatment is conservative management with physical therapy, anti-inflammatory medications, muscle relaxants, and correction of biomechanical abnormalities. However, in recalcitrant cases, a piriformis injection of anesthetic and/or corticosteroids may be considered. Because of its small size, proximity to neurovascular structures, and deep location, the piriformis muscle is often injected with the use of commuted tomography (CT), magnetic resonance imaging (MRI), ultrasound (US), fluoroscopy, electrical stimulators, or electromyography (EMG). Numerous techniques have been proposed using one or a combination of the above modalities. However, application of these techniques is limited by unavailability of CT, MRI, and EMG equipment as well as a paucity of trained physicians in US-guided procedures in many pain treatment centers throughout the United States. Fluoroscopy, however, is more widely available in this setting. This study utilized a cadaveric specimen to confirm proper needle placement for piriformis or peri-sciatic injection utilizing the previously documented landmarks for fluoroscopic guidance as described by Betts. An anteroposterior of the pelvis with inclusion of the acetabular region of the hip and the inferior aspect of the sacroiliac joint was obtained. The most superior-lateral aspect of the acetabulum and the inferior aspect of the sacroiliac joint were identified. A marker was placed one-third of the distance from the acetabular location to the inferior sacroiliac joint, indicating the target location. A 22-gauge, 3.5-inch spinal needle was directed through the gluteal muscles to the target location using intermittent fluoroscopic guidance. The posterior ileum was contacted and the needle was withdrawn 1 -2 mm. This approach found the needle within the piriformis muscle belly 2 -3 cm lateral to sciatic nerve. The present study was the first study, to our knowledge, that has confirmed the intramuscular position of the needle within the piriformis muscle of a cadaveric specimen using these anatomic landmarks and fluoroscopic guidance.
在前往疼痛诊所就诊的患者中，主诉为腰背部或臀部疼痛伴或不伴有腿部放射性症状是最常见的情况之一。梨状肌综合征在这些患者中所占比例可达8%。治疗的主要方法是采用物理治疗、抗炎药物、肌肉松弛剂以及纠正生物力学异常等保守治疗手段。然而，对于顽固病例，可考虑对梨状肌进行麻醉剂和/或皮质类固醇注射。由于梨状肌体积小、靠近神经血管结构且位置较深，在注射时常常借助计算机断层扫描（CT）、磁共振成像（MRI）、超声（US）、荧光镜检查、电刺激器或肌电图（EMG）。已经提出了许多使用上述一种或多种方式组合的技术。然而，由于CT、MRI和EMG设备的缺乏，以及在美国许多疼痛治疗中心缺乏接受过超声引导操作培训的医生，这些技术的应用受到限制。不过，荧光镜检查在这种情况下更为普及。本研究利用一具尸体标本，根据贝茨所描述的用于荧光镜引导的先前记录的体表标志，确认了梨状肌或坐骨神经周围注射时的正确进针位置。获取了包含髋关节髋臼区域和骶髂关节下侧的骨盆前后位图像。确定了髋臼最上外侧方面和骶髂关节下侧。在从髋臼位置到骶髂关节下侧距离的三分之一处放置一个标记，指示目标位置。使用间歇性荧光镜引导，将一根22号、3.5英寸的脊椎穿刺针穿过臀肌指向目标位置。穿刺针接触到回肠后部后，将针退出1 - 2毫米。这种方法发现针位于坐骨神经外侧2 - 3厘米处的梨状肌肌腹内。据我们所知，本研究是第一项使用这些解剖标志和荧光镜引导，在尸体标本的梨状肌内确认针的肌肉内位置的研究。
