Experimental Study on the Application of a Hydroxyapatite Artificial Tendon Sheath to Prevent Adhesions after Tendon Repair

用羟基磷灰石(Hap)或氧化铝陶瓷(Alm)制成的人工腱鞘，对鸡2区肌腱断裂后肌腱周围粘连的形成进行了研究。在第2区的近端和远端滑车之间切除屈肌鞘，在纤维骨隧道中形成一个窗口。深部肌腱缝合后，在缝合部位周围放置Hap或Alm鞘，然后固定3周。并与术后不使用陶瓷鞘的对照组进行比较，Hap组与Alm组的结果进行比较。从生物力学和组织学两方面对粘连形成进行评估。Hap和Alm组的肌腱活动度在所有研究时段均好于对照组。HAP和Alm鞘在肉芽组织和肌腱表面的粘附性不强。陶瓷组去除陶瓷鞘后3、6、12周组织学显示肌腱表面有上皮样结构，包括肌腱缝合部位和较宽的间隙。这个空间的外缘由一层纤维细胞样细胞和胶原纤维组成，类似于新形成的肌腱鞘。术后12周，Hap组肌腱与周围组织的间隙明显大于Alm组。术后12周组织病理学检查发现，Alm组较Hap组新形成的纤维骨管内面有更多的瘢痕形成。对照组有明显的腱周围粘连。

The formation of adhesions around the lacerated flexor tendons in zone 2 was studied in chickens after using an artificial tendon sheath made of hydroxyapatite(Hap) or alumina ceramics(Alm). The flexor sheath was excised between the proximal and distal pulley in zone 2 to create a window in the fibro-osseous tunnel. After suturing the severed profundus tendon, an Hap or Alm sheath was placed around suture site followed by 3 weeks of immobilization. The results were compared with control in which no ceramic sheaths were used after operation and the results obtained from Hap group also compared with them from Alm group. Adhesion formation was assessed both biomechanically and histologically. The mobility of tendon in both Hap and Alm group was better than in control at all the periods studied. Hap and Alm sheath was not firmly adherent to either the granulation tissue or the surface of tendon. Histology at 3, 6, and 12 weeks in ceramics group revealed epithenon-like structure on the tendon surface including the tenorrhaphy site and a wide space around the tendon after ceramics sheath was removed. The outer margins of this space was lined by a layr of fibrocyte-like cells and collagen fibers resembling new formed tendon sheath. However, Hap group showed wider space between tendon and surrounding tissue than Alm group at 12weeks after operation. Histopathological findings at 12 weeks after operation revealed the tendency to more scar formation on the inner face of the new formed fibro-osseous tunnel in Alm group than in Hap group. In the cases of control, marked peritendinous adhesion were observed.