Chin M, Toth B A
Department of Oral and Maxillofacial Surgery, California Pacific Medical Center, USA.
Plast Reconstr Surg. 1997 Sep;100(4):819-30; discussion 831-2. doi: 10.1097/00006534-199709001-00001.
The purpose of this report is to demonstrate a practical clinical method for advancement of the midface using a combination of Le Fort III osteotomy and gradual distraction. Use of internal, submergible distraction devices and modification of the Ilizarov distraction protocol are presented. Case reports show the effect of departing from the Ilizarov protocol by eliminating the latency period, initiating distraction intraoperatively, and rapidly distracting the segments postoperatively. A method of controlling fragment distraction rate by regulating pressures within the osteotomy site is described. The design and surgical application of internal distraction devices are shown. Nine patients with midface hypoplasia related to craniofacial anomalies underwent Le Fort III osteotomies assisted by gradual distraction. Ages ranged from 4 to 13 years. Custom internal distraction devices were employed to meet the unique requirements of each patient. Activation of the distraction device was accomplished by a percutaneous pin that remained in place for 3 to 5 days. The rate of transport was determined by regulating the forces within the distraction site. The internal devices remained in place for 6 months for fixation of the transported fragment. Midface advancement, measured as the anterior displacement of the infraorbital rim, ranged from 16 to 30 mm, with a mean of 20 mm. The typical force required to produce incremental movement of the Le Fort III osteotomy was found to be between 7 and 9 kg as transport exceeded 10 mm. Four patients with obstructive sleep apnea prior to surgery had resolution of the disorder. All the midface advancements remained clinically stable. Establishment of osseous continuity was verified by surgical examination in the four patients in whom the distraction devices have been removed. Combining intraoperative advancement of the Le Fort III osteotomy with gradual distraction consistently resulted in larger movements than could be achieved with conventional osteotomies and rigid fixation alone. The pediatric craniofacial skeleton responds differently to distraction than does the orthopedic skeleton. Eliminating the latency period, establishing a substantial bone gap intraoperatively, and rapidly distracting the fragment postoperatively did not adversely affect the osseous union in these patients. The internal, submergible feature of the device design offers advantages in patient acceptance, fixation stability, and wound management. This method of Le Fort III midface advancement has been shown to be clinically practical and effective.
本报告的目的是展示一种结合Le Fort III截骨术和逐步牵引来推进中面部的实用临床方法。介绍了内部可潜入式牵引装置的使用以及对Ilizarov牵引方案的改良。病例报告显示了偏离Ilizarov方案的效果，即消除延迟期、术中开始牵引并在术后快速牵引各节段。描述了一种通过调节截骨部位内压力来控制骨块牵引速率的方法。展示了内部牵引装置的设计和手术应用。9例与颅面畸形相关的中面部发育不全患者接受了Le Fort III截骨术并辅以逐步牵引。年龄范围为4至13岁。采用定制的内部牵引装置以满足每位患者的独特需求。牵引装置的激活通过一根经皮钢针完成，该钢针保留3至5天。移位速率通过调节牵引部位内的力来确定。内部装置保留6个月以固定移位的骨块。中面部推进以眶下缘的向前移位衡量，范围为16至30毫米，平均为20毫米。当移位超过10毫米时，发现使Le Fort III截骨术产生渐进性移动所需的典型力在7至9千克之间。4例术前患有阻塞性睡眠呼吸暂停的患者该病症得到缓解。所有中面部推进在临床上均保持稳定。在已取出牵引装置的4例患者中，通过手术检查证实了骨连续性的建立。将Le Fort III截骨术的术中推进与逐步牵引相结合始终能产生比单独使用传统截骨术和坚固内固定更大的移位。小儿颅面骨骼对牵引的反应与矫形骨骼不同。消除延迟期、术中建立较大的骨间隙以及术后快速牵引骨块对这些患者的骨愈合没有不利影响。装置设计的内部可潜入式特点在患者接受度、固定稳定性和伤口处理方面具有优势。这种Le Fort III中面部推进方法已被证明在临床上实用且有效。
