Jukkala-Partio Kirsi, Laitinen Outi, Vasenius Jarkko, Partio Esa K, Toivonen Terttu, Tervahartiala Pekka, Kinnunen Jaakko, Rokkanen Pentti
Department of Orthopaedics and Traumatology, Helsinki University Central Hospital, PO Box 266 (Topeliuksenkatu 5), 00029 HUS, Helsinki, Finland.
Arch Orthop Trauma Surg. 2002 Jul;122(6):360-4. doi: 10.1007/s00402-001-0379-y. Epub 2002 Feb 27.
Subcapital femoral osteotomies of ten young adult sheep were fixed with two bioabsorbable, self-reinforced, poly- L-lactide (SR-PLLA) lag screws of 4.5 mm in diameter. At 3 weeks radiographs were taken to check the reduction and fixation achieved. After follow-up periods of 12 weeks, 1 year and 3 years with three sheep in each group, and of 7 years and 4 months with one sheep, the sheep were killed, and the healing of the osteotomies, degradation and tissue response of the implants were examined radiographically, histologically and microradiographically. All osteotomies healed with a firm bony union. There was no dislocation or wound infection. Histologically, there was no marked tissue response in the bone tissue. At 12 weeks the implants were grossly intact, at 1 year granulation tissue and new bone formation had started to penetrate into the implant, and at 3 years the implant area was mostly replaced by connective tissue and new bone, but implant material was still seen as little islands surrounded by some lymphocytes. At 7 years and 4 months, the implant material had been degraded and replaced by tight bone. Self-reinforced poly- L-lactide lag screws seem to possess adequate mechanical properties and good biocompatibility for this demanding fixation.
对10只成年绵羊进行股骨转子下截骨术，并用两枚直径4.5毫米的可生物吸收、自增强聚L-丙交酯（SR-PLLA）拉力螺钉进行固定。在术后3周拍摄X线片，检查骨折复位及固定情况。每组3只绵羊分别随访12周、1年和3年，1只绵羊随访7年4个月后，将绵羊处死，通过X线摄影、组织学和显微X线摄影检查截骨处的愈合情况、植入物的降解及组织反应。所有截骨处均实现牢固骨愈合。未发生脱位或伤口感染。组织学检查显示，骨组织中无明显组织反应。术后12周时，植入物大体完整；术后1年时，肉芽组织和新骨形成开始长入植入物；术后3年时，植入物区域大多被结缔组织和新骨替代，但仍可见植入物材料呈小片状被一些淋巴细胞包围。术后7年4个月时，植入物材料已降解，被致密骨替代。自增强聚L-丙交酯拉力螺钉似乎具备满足这种高要求固定所需的足够力学性能和良好生物相容性。
