Aruwajoye Olumide O, Monte Felipe, Kim Audrey, Kim Harry K W
Department of Orthopaedics, Texas Scottish Rite Hospital for Children, Center for Excellence in Hip Disorders, University of Texas Southwestern Medical Center, TX.
J Pediatr Orthop. 2020 Apr;40(4):168-175. doi: 10.1097/BPO.0000000000001219.
Two operative procedures are currently advocated to stimulate the necrotic femoral head healing in children with Legg-Calve-Perthes disease: transphyseal neck-head tunneling (TNHT) and multiple epiphyseal drilling (MED). The purpose of this study was to compare the bone healing and physeal function after treatment with TNHT or MED in a piglet model of ischemic osteonecrosis.
Eighteen piglets were induced with osteonecrosis by surgically placing a ligature tightly around the right femoral neck. One week later, the piglets were assigned to 1 of 3 treatment groups (n=6/group): (1) local nonweight bearing only (NWB), (2) TNHT plus NWB, or (3) MED plus NWB. The unoperated left femoral heads were used as normal controls. The animals were euthanized at 8 weeks after osteonecrosis induction. Histologic, histomorphometric, radiographic, microcomputed tomography (CT), and calcein-labeling assessments were performed. Statistical analysis included a 1-way ANOVA.
Micro-CT analyses showed higher femoral head bone volume in the MED group compared with the TNHT and the NWB groups (P<0.01). The MED group had a higher mean trabecular number (P<0.001) and new bone formation (P=0.001) based on calcein-labeling parameters compared with the TNHT and the NWB groups. In addition, the osteoclast number per bone surface was lower in the MED group compared with the NWB group (P=0.001). Histologic and micro-CT assessments of the proximal femoral physis revealed a larger physeal disruption at the site of physeal drilling in the TNHT group compared with the MED group. However, no significant differences in physeal elongation (P=0.61) and femoral neck length (P=0.31) were observed between the treatment groups.
MED produced a higher bone volume and stimulated greater bone formation than the TNHT or the NWB alone. Both procedures did not produce a significant physeal growth disturbance during the study period.
This preclinical study provides evidence that MED produces more favorable bone healing than the TNHT in a large animal model of Legg-Calve-Perthes disease.
目前推荐两种手术方法来促进儿童Legg-Calve-Perthes病坏死股骨头的愈合：经骺颈-头隧道钻孔术（TNHT）和多处骨骺钻孔术（MED）。本研究的目的是在缺血性骨坏死的小猪模型中比较TNHT或MED治疗后的骨愈合和骨骺功能。
通过手术在18只小猪的右股骨颈紧密结扎诱导骨坏死。1周后，将小猪分为3个治疗组之一（每组n = 6）：（1）仅局部不负重（NWB），（2）TNHT加NWB，或（3）MED加NWB。未手术的左股骨头用作正常对照。在诱导骨坏死8周后对动物实施安乐死。进行组织学、组织形态计量学、放射学、微型计算机断层扫描（CT）和钙黄绿素标记评估。统计分析采用单因素方差分析。
微型CT分析显示，与TNHT组和NWB组相比，MED组的股骨头骨体积更高（P < 0.01）。基于钙黄绿素标记参数，与TNHT组和NWB组相比，MED组的平均小梁数量更高（P < 0.001）且新骨形成更多（P = 0.001）。此外，与NWB组相比，MED组每骨表面的破骨细胞数量更低（P = 0.001）。股骨近端骨骺的组织学和微型CT评估显示，与MED组相比，TNHT组骨骺钻孔部位的骨骺破坏更大。然而，治疗组之间在骨骺伸长（P = 0.61）和股骨颈长度（P = 0.31）方面未观察到显著差异。
与单独的TNHT或NWB相比，MED产生了更高的骨体积并刺激了更大的骨形成。在研究期间，两种手术均未产生明显的骨骺生长障碍。
这项临床前研究提供了证据，表明在Legg-Calve-Perthes病的大型动物模型中，MED比TNHT产生更有利的骨愈合。
