Majima T, Yasuda K, Fujii T, Yamamoto N, Hayashi K, Kaneda K
Department of Orthopaedic Surgery, Hokkaido University School of Medicine, Sapporo, Japan.
J Orthop Res. 1996 May;14(3):377-83. doi: 10.1002/jor.1100140306.
A rabbit model was used to discover whether the effects of stress shielding on the mechanical properties of the patellar tendon depend on the degree of stress reduction. Ninety mature female Japanese White rabbits were divided into three groups: completely stress-shielded partially stress-shielded and sham-operation and contralateral controls. In the experimental groups, tension applied to the patellar tendon was 0%, approximately 30%, and 100% of the normal tension, respectively, with a polyester artificial ligament. Tensile tests were carried out on patella-patellar tendon-tibia complexes harvested 1, 2, 3, 6, or 12 weeks after surgery. The tensile strength decreased in comparison with the sham-operation group to 50.2, 13.5, 9.7, and 20.7% in the completely stress-shielded group and to 75.2, 57.6, 59.6, 57.3, and 72.9% in the partially stress-shielded group. The tensile strength in the completely stress-shielded group was significantly less than that in the partially stress-shielded group at 1, 2, 3, and 6 weeks. The cross-sectional area of the patellar tendon significantly increased to 132, 206, 237, and 136% in the completely stress-shielded group and to 136, 170, 175, 155, and 127% in the partially stress-shielded group compared with the sham-operation group. The cross-sectional area of the completely stress-shielded tendon was significantly larger than that of the partially stress-shielded tendon at 1, 2, and 3 weeks. This study demonstrated that effects of stress shielding on the mechanical properties of the patellar tendon were dependent on the degree of stress shielding.
采用兔模型来探究应力屏蔽对髌腱力学性能的影响是否取决于应力降低程度。90只成年雌性日本白兔被分为三组：完全应力屏蔽组、部分应力屏蔽组、假手术组及对侧对照组。在实验组中，通过聚酯人工韧带分别向髌腱施加0%、约30%和100%的正常张力。对术后1、2、3、6或12周采集的髌-髌腱-胫骨复合体进行拉伸试验。与假手术组相比，完全应力屏蔽组的拉伸强度分别降至50.2%、13.5%、9.7%和20.7%，部分应力屏蔽组分别降至75.2%、57.6%、59.6%、57.3%和72.9%。在术后1、2、3和6周时，完全应力屏蔽组的拉伸强度显著低于部分应力屏蔽组。与假手术组相比，完全应力屏蔽组髌腱的横截面积显著增加至132%、206%、237%和136%，部分应力屏蔽组分别增加至136%、170%、175%、155%和127%。在术后1、2和3周时，完全应力屏蔽组髌腱的横截面积显著大于部分应力屏蔽组。本研究表明，应力屏蔽对髌腱力学性能的影响取决于应力屏蔽程度。
