Tohyama Harukazu, Yasuda Kazunori, Kitamura Yoshiaki, Yamamoto Ei, Hayashi Kozaburo
Department of Sports Medicine and Joint Reconstruction Surgery, Hokkaido University School of Medicine, Kita-15 Nishi-7, Sapporo, 060-8638, Japan.
Clin Biomech (Bristol). 2003 Oct;18(8):765-72. doi: 10.1016/s0268-0033(03)00055-x.
To know the temporal changes of the mechanical properties of the regenerated and the residual tissues in the patellar tendon after removal of the central portion.Design. The regenerated and the residual tissues were compared to sham-operated tendons.
Although the structural properties of the whole patellar tendon after removal of the central portion have been investigated, no studies have distinguished between the regenerated and the residual tissues.Methods. For 52 skeletally mature rabbits, a full-thick, segmental defect was made at the central portion of the right patellar tendon, while a sham operation performed in the left tendon. At 3, 6, 12, and 24 weeks, we evaluated the mechanical properties and fibroblast density of the regenerated and the residual tissues as well as the blood flow and tissue dimensions of the patellar tendon. In addition, non-treated patellar tendons from six rabbits were served as the control for mechanical testing.
The tangent modulus and the tensile strength of the regenerated tissue progressively increased with time. On the other hand, these parameters of the residual tendinous portion decreased until 6 weeks, although they gradually increased thereafter. The tensile strength of the regenerated and the residual tissues at 24 weeks were approximately 80% and 75%, respectively, of the non-treated, control tendon. Abundant blood flow and cell proliferation were observed in the regenerative tissue until 6 weeks.
The mechanical properties of the regenerated and the residual tissues after removal of the central portion in the patellar tendon are much different from those of the original tendon.
The present study showed inferior mechanical properties of the residual and the regenerated tissues for up to 24 weeks after removal of the central portion in the patellar tendon. Therefore, the aggressive rehabilitation that applies excessive load to the patellar tendon should be avoided at an early stage after harvesting the tendon for ligament reconstruction.
了解髌腱中央部分切除后再生组织和残留组织力学性能的时间变化。设计。将再生组织和残留组织与假手术肌腱进行比较。
尽管已经对髌腱中央部分切除后整个髌腱的结构特性进行了研究，但尚无研究区分再生组织和残留组织。方法。对52只骨骼成熟的兔子，在右髌腱中央部分制造全层节段性缺损，而在左腱进行假手术。在3、6、12和24周时，我们评估了再生组织和残留组织的力学性能、成纤维细胞密度以及髌腱的血流和组织尺寸。此外，将6只兔子未经处理的髌腱用作力学测试的对照。
再生组织的切线模量和拉伸强度随时间逐渐增加。另一方面，残留腱部的这些参数在6周前下降，尽管此后逐渐增加。24周时再生组织和残留组织的拉伸强度分别约为未处理对照肌腱的80%和75%。直到6周时，在再生组织中观察到丰富的血流和细胞增殖。
髌腱中央部分切除后再生组织和残留组织的力学性能与原始肌腱有很大不同。
本研究表明，髌腱中央部分切除后长达24周，残留组织和再生组织的力学性能较差。因此，在采集肌腱用于韧带重建后的早期阶段，应避免对髌腱施加过大负荷的积极康复训练。
