Tissue memory in healing tendons: short loading episodes stimulate healing

2009 ◽  
Vol 107 (2) ◽  
pp. 417-421 ◽  
Author(s):  
Therese Andersson ◽  
Pernilla Eliasson ◽  
Per Aspenberg
Keyword(s):  
Achilles Tendon ◽  
Mechanical Loading ◽  
Achilles Tendon Rupture ◽  
Peak Force ◽  
Treadmill Running ◽  
Female Rats ◽  
Full Time ◽  
Time Activity ◽  
Cage Activity ◽  
Daily Training

Intact tendons adapt slowly to changes in mechanical loading, whereas in healing tendons the effect of mechanical loading or its absence is dramatic. The longevity of the response to a single loading episode is, however, unknown. We hypothesized that the tissue has a “memory” of loading episodes and that therefore short loadings are sufficient to elicit improved healing. The Achilles tendon of 70 female rats was transected and unloaded by tail suspension for 12 days (suspension started on day 2 after surgery). Each day, the rats were let down from suspension for short daily training episodes according to different regimes: 15 min of cage activity or treadmill running for 15, 30, 60, or 2 × 15 min. Rats with transected Achilles tendons and full-time cage activity served as controls. The results demonstrated that full-time cage activity increased the peak force over three times compared with unloading. Short daily loading episodes (treadmill running) increased the peak force about half as much as full-time activity. Prolongation of treadmill running above 15 min or dividing the daily training in two separate episodes had minimal further effect. This mechanical stimulation increased the cross-sectional area but had no effect on the mechanical properties of the repair tissue. The findings indicate that once the tissue had received information from a certain loading type and level, this is “memorized” and leads to a response lasting many hours. This suggests that patients might be allowed early short loading episodes following, e.g., an Achilles tendon rupture for a better outcome.

scholarly journals Different gene response to mechanical loading during early and late phases of rat Achilles tendon healing

2017 ◽  
Vol 123 (4) ◽  
pp. 800-815 ◽  
Author(s):  
M. Hammerman ◽  
P. Blomgran ◽  
A. Dansac ◽  
P. Eliasson ◽  
P. Aspenberg
Keyword(s):  
Transcription Factors ◽  
Achilles Tendon ◽  
Mechanical Loading ◽  
Tendon Healing ◽  
Treadmill Running ◽  
Inflammatory Phase ◽  
Gene Response ◽  
Healing Phase ◽  
Two Phases ◽  
The Right

Mechanical loading stimulates tendon healing both when applied in the inflammatory phase and in the early remodeling phase of the process, although not necessarily via the same mechanisms. We investigated the gene response to mechanical loading in these two phases of tendon healing. The right Achilles tendon in rats was transected, and the hindlimbs were unloaded by tail suspension. The rats were exposed to 5 min of treadmill running 3 or 14 days after tendon transection. Thereafter, they were resuspended for 15 min or 3 h until euthanasia. The controls were suspended continuously. Gene analysis was first performed by microarray analysis followed by quantitative RT-PCR on selected genes, focusing on inflammation. Fifteen minutes after loading, the most important genes seemed to be the transcription factors EGR1 and C-FOS, regardless of healing phase. These transcription factors might promote tendon cell proliferation and differentiation, stimulate collagen production, and regulate inflammation. Three hours after loading on day 3, inflammation was strongly affected. Seven inflammation-related genes were upregulated according to PCR: CCL20, CCL7, IL-6, NFIL3, PTX3, SOCS1, and TLR2. These genes can be connected to macrophages, T cells, and recruitment of leukocytes. According to Ingenuity Pathway Analysis, the recruitment of leukocytes was increased by loading on day 3, which also was confirmed by histology. This inflammation-related gene response was not seen on day 14. Our results suggest that the immediate gene response after mechanical loading is similar in the early and late phases of healing but the late gene response is different. NEW & NOTEWORTHY This study investigates the direct effect of mechanical loading on gene expression during different healing phases in tendon healing. One isolated episode of mechanical loading was studied in otherwise unloaded healing tendons. This enabled us to study a time sequence, i.e., which genes were the first ones to be regulated after the loading episode.

scholarly journals Effect of Running with Different Intensities on Lubricin Expression of Achilles Tendon in a Rat Model

2020 ◽  
Author(s):  
Shao-Yong Xu ◽  
Cheng-Xian Song ◽  
Song-Yun Deng ◽  
Sheng-Yao Liu ◽  
Wei Liu ◽  
...  
Keyword(s):  
Achilles Tendon ◽  
Mechanical Loading ◽  
Rat Model ◽  
Biochemical Analysis ◽  
Tendon Rupture ◽  
Transmission Efficiency ◽  
Treadmill Running ◽  
Histological Observation ◽  
And Control ◽  
Tgf Β1

Abstract Background: Lubricin is well known to facilitate the movement of tendon fascicles gliding and recoil against the surrounding tissues in tendons. However, little is known about its response under various mechanical loading conditions. This study was aimed to understand the effect of treadmill running with different exercise intensities on the alternations of lubricin content in rat Achilles tendon.Methods: In this study, eighteen rats were randomly divided into three groups, strenuous treadmill running (STR), moderate treadmill running (MTR), and control (CON). Rats in two running groups were subjected to treadmill running (8 weeks) protocol. Histological observation and biochemical analysis were conducted using the collected Achilles tendons.Results: After 8 weeks, the morphologies of collagen fibers are relatively parallel, crimping and elastic in the CON and MTR groups, but more ruptured in the STR group. The cell density in Achilles tendon sections markedly increased in MTR group than CON group, whereas considerably decreased in STR group than CON or MTR group. Additionally, compared to the CON group, the content of lubricin was dramatically increased in MTR group. However, the lubricin content in STR group was markedly decreased compared with that in CON or MTR group. Moreover, the TGF-β1 expression was upregulated in MTR group in contrast to CON group, while significantly downregulated in STR group than that in CON or MTR group. Conversely, the expression of IL-1 was statistically downregulated in MTR group compared with CON group, but statistically upregulated in STR group than that in CON or MTR group. Conclusions: These results suggest that moderate treadmill running might induce the increase of lubricin by the up-regulation of TGF-β1 expression to improved lubrication, and enhance the loading transmission efficiency. Whereas, strenuous treadmill running could result in the decrease of lubricin as a result of the dramatically increased expression of IL-1 to enhance interfascicular tribology, and predispose to tendinopathy even tendon rupture.

scholarly journals Operative Outcome of Side-Locking Loop Suture Technique Accompanied by Autologous Semitendinosus Tendon Grafting for Chronic Rupture of Achilles Tendon

2021 ◽  
Vol 6 (2) ◽  
pp. 247301142110035
Author(s):  
Keisuke Tsukada ◽  
Youichi Yasui ◽  
Maya Kubo ◽  
Shinya Miki ◽  
Kentaro Matsui ◽  
...  
Keyword(s):  
Achilles Tendon ◽  
Scale Score ◽  
Tendon Rupture ◽  
Plantar Flexion ◽  
Achilles Tendon Rupture ◽  
Case Series ◽  
Semitendinosus Tendon ◽  
Level Of Evidence ◽  
Operative Outcomes

Background: The purpose of this retrospective study was to clarify the operative outcomes of the side-locking loop suture (SLLS) technique accompanied by autologous semitendinosus tendon grafting for chronic Achilles tendon rupture. Methods: A chart review was conducted of consecutive patients treated with the SLLS technique at our department from 2012 to 2017. Postoperatively, a below-knee splint was applied for 2 weeks in 20 degrees of plantar flexion and then active range of motion exercise was started. Partial weightbearing exercise was allowed at 4 weeks according to patient tolerance, and full weightbearing without crutches was allowed at 8 weeks. The American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scale score and the Achilles tendon rupture score (ATRS) were used to evaluate clinical outcomes preoperatively and at the final follow-up. Results: Ten patients (6 men, 4 women) were included in the analysis. Mean AOFAS ankle-hindfoot scale score increased significantly from 64.2 ± 5.6 points preoperatively to 95.0 ± 5.3 points at the final follow-up ( P < .001). The mean ATRS also increased significantly from 29.8 ± 4.4 points to 86.2 ± 7.7 points, respectively ( P < .001). Mean time between surgery and ability to perform 20 continuous double-leg heel raises of the operated foot was 13.5 ± 3.4 (range 10-18) weeks. One patient complained of postoperative hypoesthesia in the foot, which had spontaneously resolved by 3 months after surgery. Conclusion: The SLLS technique accompanied by autologous semitendinosus tendon grafting provided successful operative outcomes for patients with chronic Achilles tendon rupture regardless of the size of the defect, and thus long-term orthotic use was not needed after surgery. Level of Evidence: Level IV, retrospective case series.

scholarly journals Concomitant Partial Achilles Tendon Rupture and Lateral Luxation of the Superficial Digital Flexor Muscle Tendon in a Dog

VCOT Open ◽  
2021 ◽  
Vol 04 (01) ◽  
pp. e37-e40
Author(s):  
Hélène Dosseray ◽  
Claire Deroy-Bordenave
Keyword(s):  
Achilles Tendon ◽  
Achilles Tendon Rupture ◽  
Simultaneous Occurrence ◽  
Flexor Muscle ◽  
Screw Insertion ◽  
Superficial Digital Flexor Tendon ◽  
Fixation Screw ◽  
Pelvic Limb ◽  
The Right

AbstractThe aim of this study was to report a posttraumatic partial Achilles tendon (AT) rupture associated with lateral luxation of the superficial digital flexor tendon (SDFT) in a Whippet. This article is a brief communication. A Whippet was presented with posttraumatic plantigrade stance and non-load-bearing lameness of the right pelvic limb. The objective findings consisted in partial AT rupture and SDFT lateral luxation. Surgical treatment ensued: tenorrhaphy of the torn tendons and calcaneo-tibial screw insertion for tarsal immobilization, followed by suturing of the SDFT retinaculum. A casting bandage was employed for additional immobilization. Nonetheless, a bandage complication prompted the premature removal of the fixation screw and casting wrap. Complete functional recovery was achieved by the 20th postoperative week. The simultaneous occurrence of SDFT luxation and partial AT tear has not been reported in the literature before. The long-term postoperative functional outcome was highly satisfactory.

Sign in / Sign up

Export Citation Format

Share Document