Department of Orthopedic Surgery, University of Basel, Basel, Switzerland.
Rehabilitation Medicine Research Center, Mayo Clinic, Rochester, Minnesota, USA.
Am J Sports Med. 2019 Feb;47(2):462-467. doi: 10.1177/0363546518814534. Epub 2018 Dec 14.
The paratenon is important for Achilles tendon healing. There is much interest in the use of exogenous growth factors (GFs) as potential agents for accelerating the healing of damaged Achilles tendons.
PURPOSE/HYPOTHESIS: The present study used a rat model to study the responses of the injured Achilles tendon to GFs in the presence or absence of the paratenon. The hypothesis was that responses of the injured tendon to GFs would be lower in the absence of a paratenon.
Controlled laboratory study.
A 4-mm defect was created in the right Achilles tendon of 60 skeletally mature rats, which were treated with a validated combination of GFs (bFGF, BMP-12, and TGF-β1). Animals were randomly assigned to the intact paratenon (IP) group or resected paratenon (RP) group. Healing was studied anatomically, mechanically, and histologically after 1, 2, and 4 weeks.
IP tendons showed improved healing compared with RP tendons. IP tendons were significantly stronger (32.2 N and 48.9 N, respectively) than RP tendons (20.1 N and 31.1 N, respectively) after 1 and 2 weeks. IP tendons did not elongate as much as RP tendons and had greater cross-sectional areas (18.0 mm, 14.4 mm, and 16.4 mm, respectively) after 1, 2, and 4 weeks compared with RP tendons (10.5 mm, 8.4 mm, and 11.9 mm, respectively). On histology, earlier collagen deposition and parallel orientation of fibrils were found for IP tendons.
The paratenon is essential for efficient Achilles tendon healing. Healing with GFs in this Achilles tendon defect model was superior in the presence of the paratenon.
Biological approaches to tendon engineering using GFs are in vogue and have been shown to improve healing of the rat Achilles tendon, most likely by inducing progenitor cells located within the paratenon. Clinically, resection or incision of the paratenon has been proposed for wound closure. Our data demonstrate the fundamental importance of the paratenon, which therefore should be preserved during Achilles tendon repair, especially if augmented with products such as platelet-rich plasma or autologous conditioned serum that are rich in GFs.
滑囊对于跟腱愈合很重要。人们对使用外源性生长因子（GFs）作为加速受损跟腱愈合的潜在药物很感兴趣。
目的/假设：本研究使用大鼠模型研究了滑囊存在或不存在时，受伤跟腱对 GFs 的反应。假设是，如果没有滑囊，受伤跟腱对 GFs 的反应会降低。
对照实验室研究。
在 60 只骨骼成熟的大鼠右侧跟腱上造成 4mm 的缺损，并用经过验证的 GFs（bFGF、BMP-12 和 TGF-β1）混合物进行治疗。动物被随机分配到完整滑囊（IP）组或切除滑囊（RP）组。在 1、2 和 4 周后进行解剖学、力学和组织学研究。
IP 肌腱的愈合情况优于 RP 肌腱。IP 肌腱在 1 周和 2 周后分别比 RP 肌腱（分别为 20.1N 和 31.1N）更强壮（分别为 32.2N 和 48.9N）。IP 肌腱的伸长程度不如 RP 肌腱，在 1、2 和 4 周后，其横截面积也较大（分别为 18.0mm、14.4mm 和 16.4mm），而 RP 肌腱的横截面积分别为 10.5mm、8.4mm 和 11.9mm。组织学上，IP 肌腱的胶原沉积较早，纤维呈平行排列。
滑囊对跟腱的有效愈合至关重要。在滑囊存在的情况下，这种跟腱缺损模型中的 GFs 愈合效果更好。
使用 GFs 的肌腱工程生物学方法正在流行，并已被证明可改善大鼠跟腱的愈合，这很可能是通过诱导位于滑囊内的祖细胞。临床上，为了闭合伤口，已经提出了切除或切开滑囊。我们的数据证明了滑囊的基本重要性，因此在跟腱修复过程中应保留滑囊，特别是在使用富含 GFs 的富血小板血浆或自体条件血清等产品进行增强时。
