S2 iliosacral screw insertion technique / 中国骨伤

<p><b>OBJECTIVE</b>To introduce a technique pertaining to S2 iliosacral screw insertion.</p><p><b>METHODS</b>The screw pathway was first measured on the preoperative pelvic CT scan or the standard sacral lateral radiograph to make sure the existence of the "safe zone" in the S2 segment for screw insertion. Under general anesthesia, patients were positioned supine or prone, depending on the injury pattern of pelvic ring or associated injuries requiring concomitant operation. The operation field was routinely sterilized using iodine and subsequent alcohol solution and draped. The tip of a guide wire was inserted through a stab wound to the posterior outer iliac table, manipulated in the "safe zone" being enclosed by the anterior aspect of the S2 nerve root tunnel, the anterior aspect of the sacral vertebrae, and the inferior aspect of the S1 foramen under the guidance of the standard sacral lateral fluoroscopy, and then the tip was hammered one to two millimeters into the iliac cortex. The guide wire progressed along the trajectory between the inferior aspect of the S1 foramen and the superior aspect of the S2 foramen on the pelvic outlet fluoroscopic view, and then along the posterior to the anterior aspect of the S2 sacral vertebrae and alae on the pelvic inlet fluoroscopic view with a predetermined length. At that moment, in order to ensure the safety, another standard sacral lateral view was imaged to detect the guide wire's tip which should locate posterior to the anterior aspect of the sacral vertebrae and anterior to the anterior aspect of the S2 nerve root tunnel. Subsequently, the depth was measured, the trajectory was drilled and tapped, and the screw was inserted. Following the removal of the guide wire, the wound was irrigated and sutured.</p><p><b>RESULTS</b>Utilizing this insertion technique, there were 30 S2 iliosacral screws in total being placed to stabilize the injured and unstable posterior pelvic ring in 27 patients. Each S2 screw was accompanied by an ipsilateral S1 screw. The S2 screw location was completely intraosseous in all patients, which was verified by postoperative pelvic outlet and inlet radiographs and CT scans. The insertion accuracy was 100 percent in the present series.</p><p><b>CONCLUSION</b>The S2 iliosacral screw insertion technique is safe and reproducible to guide the placement of the S2 screw, enhancing the stability for the compromised posterior pelvic ring.</p>

Application of minimally invasive, decompression bone graft implantation combined with metal trabecular bone reconstruction system for early stage osteonecrosis of femoral head / 中国骨伤

<p><b>OBJECTIVE</b>To observe the application effect of minimally invasive decompression, bone graft implantation and metal trabecular bone reconstruction system for early stage osteonecrosis of femoral head and discuss the treatment of hip-salvage operation in early stage osteonecrosis of femoral head;</p><p><b>METHODS</b>From January 2010 to June 2011, 50 patients (62 hips) Which were osteonecrosis of femoral head of early stake,were treated with minimally invasive decompression, bone graft implantation and metal trabecular bone reconstruction system, including 31 males (40 hips), 19 females (22 hip) with an average age of 36.2 years old ranging from 22 to 54 years old. The course of disease was from 6 to 15 months (averaged 10.5 months). Among them, 19 cases (23 hips) were steroid-induced, 25 cases (33 hips) were alcohol-induced, 6 cases (6 hips) were idiopathic; According to ARCO stage, 28 hips were at stage I, 34 hips were at stage II. All of them were diagnosed as femoral head necrosis by imaging examination before operation. Then each patient was followed to assess by Harris hip score, curative effect, and conduct the femoral head survival analysis during the postoperation.</p><p><b>RESULTS</b>All patients had finished operation, the operation time was between 30 and 85 min, intraoperative blood loss was 50 to 220 ml, and 47 cases (58 hips) were follow-up from 24 to 46 months with an average of 34.05 months. As compared with preoperative, the Harris hip score at the last follow-up was improved, the difference was statistically significant (P<0.01). The Harris hip score, curative effect and survival time of femoral head in ARCO stage I was superior to these in ARCO Stage II, the difference was statistically significant (P< 0.05).</p><p><b>CONCLUSION</b>Effect of minimally invasive decompression,bone graft implantation combine with the metal trabecular bone reconstruction system for early stage osteonecrosis of femoral head was good,it could significantly improve the Harris hip score, increase the femoral head survival time, delay the hip replacement, and performance better in ARCO stage I.</p>