Gait analysis combined with the expression of TGF-β1, TGF-β3 and CREB during Achilles tendon healing in rat

PurposeTo observe the changes of gait behavior and the expression of wound healing factors of transforming growth factor-β1 (TGF-β1), TGF-β3 and cAMP response element binding protein-1 (CREB-1) during the healing of Achilles tendon in a rat model, and to investigate whether gait analysis can be used to evaluate the tendon healing.MethodsAchilles tendon of 40 healthy male Sprague-Dawley rats were transected and sutured to establish the Achilles tendon injury (ATI) model. They were randomly divided into 4 groups based on the observational time point at 1, 2, 4 and 6 weeks after injury (n = 10 for each group). Before modeling, 9 rats were randomly selected for CatWalk gait analysis, which contained step cycle, single stance time and average speed. Data were recorded as the normal controls. After then, ATI models were established in the left hind limbs of the all 40 rats (ATI group), while the right hind limbs were only cut and sutured without injury of the Achilles tendon (sham operation group). At 1, 2, 4 and 6 weeks after injury, the gait behavior of the corresponding group of rats (n = 9) as observed and recorded by CatWalk platform. After then, the rats were sacrificed and Achilles tendon of both limbs was harvested. The tendon healing was observed by gross anatomy and histological examination, and the protein and mRNA expression of TGF-β1, TGF-β3, CREB-1 were observed by immunohistochemistry and qPCR. The results of tendon gross grading were analyzed by Wilcoxon rank sum test, and other data were analyzed by one-way analysis of variance among multiple groups.ResultsCompared with normal controls, all gait indexes (step cycle, single stance time and average speed) were greatly affected following ATI, which however improved with time. The step cycle was significantly lower at 1, 2 and 4 weeks after ATI (compared with normal controls, all p < 0.05), but almost returned to the normal level at 6 weeks ((0.694 ± 0.102) vs. (0.503 ± 0.094) s, p > 0.05). The single stance time of the ATI group was significantly shorter at 1 and 2 weeks after operation ((0.078 ± 0.010) s at 1 week, (0.078 ± 0.020) s at 2 weeks, all p < 0.001) and revealed no significant difference at 4 weeks (p = 0.120). The average speed of ATI group at 1, 2, 4, 6 weeks was significantly lower than that in the normal control group (all p < 0.001).Gross observation showed that the grade of local scar adhesion in ATI group increased significantly at 2, 4 and 6 weeks, compared with the sham operation group (all p < 0.001). Extensive adhesion was formed at 6 weeks after ATI. The results of HE staining showed that the number of fibroblast increased gradually and arranged more orderly in ATI group at 1, 2 and 4 weeks (all p < 0.001), and decreased at 6 weeks, but it was still significantly higher than that of the sham operation group (p < 0.001). Immunohistochemistry showed that the positive expression of TGF-β1, TGF-β3, CREB-1 in ATI group was higher than that in the sham operation group at 4 time points (all p < 0.05), which reached the peak at 2 weeks after operation and decreased at 4 weeks (p = 0.002, p < 0.001, p = 0.041, respectively). The results of qPCR suggested that the mRNA expression of TGF-β1, TGF-β3, CREB-1 in ATI group was higher than that in the sham operation group at all-time points (all p < 0.05), which reached the peak at 2 weeks after operation, decreased at 4 weeks, and significantly decreased at 6 weeks (all p < 0.001).ConclusionGait behavior indexes are associated with Achilles tendon healing. The study gives an insight of TGF-β1, TGF-β3, CREB-1 changes in the coursing of Achilles tendon healing and these cytokines may be able to be used to regulate the Achilles tendon healing.     

Gait analysis combined with the expression of TGF-β1, TGF-β3 and CREB during Achilles tendon healing in rat

PurposeTo observe the changes of gait behavior and the expression of wound healing factors of transforming growth factor-β1 (TGF-β1), TGF-β3 and cAMP response element binding protein-1 (CREB-1) during the healing of Achilles tendon in a rat model, and to investigate whether gait analysis can be used to evaluate the tendon healing.MethodsAchilles tendon of 40 healthy male Sprague-Dawley rats were transected and sutured to establish the Achilles tendon injury (ATI) model. They were randomly divided into 4 groups based on the observational time point at 1, 2, 4 and 6 weeks after injury (n = 10 for each group). Before modeling, 9 rats were randomly selected for CatWalk gait analysis, which contained step cycle, single stance time and average speed. Data were recorded as the normal controls. After then, ATI models were established in the left hind limbs of the all 40 rats (ATI group), while the right hind limbs were only cut and sutured without injury of the Achilles tendon (sham operation group). At 1, 2, 4 and 6 weeks after injury, the gait behavior of the corresponding group of rats (n = 9) as observed and recorded by CatWalk platform. After then, the rats were sacrificed and Achilles tendon of both limbs was harvested. The tendon healing was observed by gross anatomy and histological examination, and the protein and mRNA expression of TGF-β1, TGF-β3, CREB-1 were observed by immunohistochemistry and qPCR. The results of tendon gross grading were analyzed by Wilcoxon rank sum test, and other data were analyzed by one-way analysis of variance among multiple groups.ResultsCompared with normal controls, all gait indexes (step cycle, single stance time and average speed) were greatly affected following ATI, which however improved with time. The step cycle was significantly lower at 1, 2 and 4 weeks after ATI (compared with normal controls, all p < 0.05), but almost returned to the normal level at 6 weeks ((0.694 ± 0.102) vs. (0.503 ± 0.094) s, p > 0.05). The single stance time of the ATI group was significantly shorter at 1 and 2 weeks after operation ((0.078 ± 0.010) s at 1 week, (0.078 ± 0.020) s at 2 weeks, all p < 0.001) and revealed no significant difference at 4 weeks (p = 0.120). The average speed of ATI group at 1, 2, 4, 6 weeks was significantly lower than that in the normal control group (all p < 0.001).Gross observation showed that the grade of local scar adhesion in ATI group increased significantly at 2, 4 and 6 weeks, compared with the sham operation group (all p < 0.001). Extensive adhesion was formed at 6 weeks after ATI. The results of HE staining showed that the number of fibroblast increased gradually and arranged more orderly in ATI group at 1, 2 and 4 weeks (all p < 0.001), and decreased at 6 weeks, but it was still significantly higher than that of the sham operation group (p < 0.001). Immunohistochemistry showed that the positive expression of TGF-β1, TGF-β3, CREB-1 in ATI group was higher than that in the sham operation group at 4 time points (all p < 0.05), which reached the peak at 2 weeks after operation and decreased at 4 weeks (p = 0.002, p < 0.001, p = 0.041, respectively). The results of qPCR suggested that the mRNA expression of TGF-β1, TGF-β3, CREB-1 in ATI group was higher than that in the sham operation group at all-time points (all p < 0.05), which reached the peak at 2 weeks after operation, decreased at 4 weeks, and significantly decreased at 6 weeks (all p < 0.001).ConclusionGait behavior indexes are associated with Achilles tendon healing. The study gives an insight of TGF-β1, TGF-β3, CREB-1 changes in the coursing of Achilles tendon healing and these cytokines may be able to be used to regulate the Achilles tendon healing.     

富血小板血浆对大鼠跟腱断裂早期愈合的影响

目的富血小板血浆(platelet-rich plasma,PRP)具有促进损伤组织修复作用。通过观察PRP局部注射对大鼠跟腱断裂早期愈合的影响,为临床应用提供实验依据。方法 SPF级SD大鼠46只,雌雄不限,体重190～240 g。取10只大鼠心脏动脉血制备PRP及贫血小板血浆(platelet-poor plasma,PPP);其余36只随机分为3组(n=12),分别为空白对照组、PPP组及PRP组。大鼠制备双侧跟腱断裂模型后,PPP组和PRP组跟腱周围局部对应注射PPP及PRP,每侧100μL,每周1次至处死;空白对照组不作处理。术后观察大鼠一般情况,于1、2、3、4周取双侧跟腱,行大体、组织学及免疫组织化学染色观察,测量新生跟腱Ⅰ型胶原纤维含量;并于4周行生物力学测试。结果大鼠均存活至实验完成。随着时间延长,各组大鼠跟腱水肿逐渐减退,滑动性逐渐改善;术后3周内各组跟腱粘连逐渐加重,4周时减轻,1、4周时各组跟腱粘连程度分级差异均无统计学意义(P>0.05)。术后1周PRP组炎性细胞浸润、毛细血管及胶原纤维增殖较空白对照组、PPP组明显,之后炎性反应及毛细血管生成逐渐减少。各时间点各组均可见Ⅰ型胶原纤维阳性表达,术后1、2、3周PRP组Ⅰ型胶原纤维阳性密度值多于空白对照组和PPP组(P<0.05),4周时3组差异无统计学意义(P>0.05)。生物力学测试:术后4周3组跟腱最大滑动距离比较,差异均无统计学意义(P>0.05);PRP组跟腱弹性模量及最大抗拉力明显高于空白对照组及PPP组(P<0.05)。结论大鼠跟腱断裂早期于断端周围注射PRP能促进跟腱愈合。     

Pulsed ultrasound treatment accelerates the repair of Achilles tendon rupture in rats.

A rat tenotomy model was used to investigate the effect of combined conservative management and pulsed ultrasound (PUS) on the repair of tenotomized Achilles tendon. Hemitenotomy of right medial Achilles tendon was performed in 48 rats without suture, and patella tenotomy was performed to mimic immobilization and limb disuse of an injured limb. PUS and sham PUS were applied to the healing wound for the treatment group and control group for 5 min, 3 times per week for 2 or 4 weeks, respectively. Tensile tests showed that the ultimate tensile strength (UTS) and stiffness of the repaired tendon in the treatment group at 2 weeks reached 48.92+/-8.39% and 62.48+/-32.46% of the contralateral normal tendon strength, which were significantly higher than those of the control group (UTS, 30.36+/-15.46%; stiffness, 33.90+/-17.59; p<0.05). At 4 weeks, UTS increased to 77.09+/-15.31% and stiffness to 92.48+/-31.12% in the treatment group, significantly higher than those in the control group (UTS, 54.33+/-18.40%, p<0.01; stiffness, 65.02+/-25.48%, p<0.05). Light microscopy revealed more regular, denser, and better aligned collagen fibers in the healing scar of the PUS-treated healing tendons. The findings suggested that PUS were able to accelerate the healing of the ruptured tendons.     

Early rehabilitation after open repair for patients with a rupture of the Achilles tendon

PurposeAs outdoor activities participation increase, Achilles tendon rupture incidence also tends to increase. There are a number of treatment and rehabilitation options for a ruptured Achilles tendon. However, the optimal rehabilitation protocols are still under debate. The purpose of this study is to determine whether early rehabilitation is more effective than conventional rehabilitation.MethodsMedical records of 56 patients who had been treated with open repair after a ruptured Achilles tendon were retrospectively reviewed. 24 patients were treated postoperatively with below knee cast immobilization for four weeks, and they started tolerable weight-bearing rehabilitation at four weeks’ follow-up. The remaining 32 patients were managed postoperatively with short leg splint immobilization for two weeks and started the tolerable weight-bearing at two weeks’ follow-up. We evaluated the patients several times to identify when the single heel raise was possible and measured the American Orthopedic Foot and Ankle Society (AOFAS) scores and Achilles tendon total rupture scores (ATRS) as a functional outcome.ResultsThe single heel raise test was positive in all patients at the last assessment. But there were no statistically significant differences between the groups (p = 0.137). The patients in the Cast group took significantly more time to return to work than did the patients in the Splint group (p = 0.032). And AOFAS scores and ATRS were slightly higher in the Splint group than in the Cast group. There were statistically significant differences (p = 0.042, p = 0.028) between the two groups.ConclusionThe early rehabilitation did not lead to greater endurance, but it showed better results in the return to work and the Achilles functional score. Early rehabilitation after open repair for patients with a ruptured Achilles tendon is helpful for functional recovery.Type of study / Level of evidence: Therapeutic, Level III.     

Biomechanical and histologic comparison of Achilles tendon ruptures reinforced with intratendinous and peritendinous plantaris tendon grafts in rabbits: an experimental study

Introduction We hypothesized that the closer the reinforcing graft was to the repair zone, the more strength the healed tendon would achieved. Therefore, we compared the ruptured rabbit Achilles tendons reinforced with intratendinous and peritendinous plantaris grafts.Materials and methods The experimental study was performed on Achilles tendons of 20 rabbits. First, they were divided into two groups: group I (n=10) underwent intratendinous graft and end-to-end tenorraphy, and group P (n=10) were repaired end-to-end and then reinforced with a peritendinous plantaris graft. An above-knee cast was applied during 6 weeks postoperatively. The two groups were compared to each other biomechanically and histologically. Seven randomly selected rabbits from each group were used for biomechanical evaluation. The remaining six rabbits (three from each group) were used for histologic comparison. Non-operated sides (n=20) served as the control group.Results The mean maximum load at rupture of the repaired and control groups was 159.9±31 N, 83±7.5 N, and 207.5±35 N for group I, group P, and the control group, respectively. Values between groups were significantly different considering maximum load and absorbed energy to rupture. There was no significant difference between groups I and P in respect to strain. Control group tendons (groups I-C and P-C) had significantly more lengthening capability than operated tendons. Macroscopically, group I tendons were thicker and stiffer than group P tendons. Histologically, differences between the group I and group P specimens revealed that the healing process was faster in tendons augmented intratendinously.Conclusions In reinforcing Achilles tendon repair, the site of the tendon graft affected the result. When the graft was used intratendinously, the healed tendon was more similar biomechanically to normal tendon and had more graft-tendon orientation histologically than the tendon augmented peritendinously.This study was performed at the Biomechanic Laboratory of Middle East Technical University (METU) and Animal Experimental Research Laboratory of Osmangazi University in Turkey. The experiments comply with the current law of our country     

Investigation of the biomechanical and histopathological effects of autologous conditioned serum on healing of Achilles tendon

Objective

The aim of this study to evaluate the effects of autologous conditioned serum (ACS) on the healing of transected rat Achilles tendons via the assessment of biomechanical and histological parameters.

Sex matters in the establishment of murine tendon composition and material properties during growth

The existence of sex‐based differences in tendon and ligament injury rates has led investigators to test the hypothesis that sex plays a significant role in modulating tendon and ligament composition and material properties. To date, no studies have attempted to characterize how such differences develop during the course of normal tissue maturation and growth. Thus, the primary aim of the present study was to use a murine model to test the hypothesis that sex‐based differences in the normal age‐related development of tendon composition and material properties exist by assessing these parameters in the Achilles and tail tendons from 4‐, 6‐, 9‐, 12‐, and 15‐week‐old male and female C57Bl/6J mice. Despite significantly lower levels of total collagen content in females subsequent to sexual maturity (p < 0.0001), as well as a significant effect of sex on glycosaminoglycan content (p < 0.0001), Achilles tendon elastic modulus was not compromised in females. Female Achilles tendons did exhibit a significantly higher failure strain (p = 0.0201) and strain energy density (p = 0.0004) than did males, as well as a trend toward higher ultimate strength (p = 0.0556). In contrast to the high load‐bearing environment of the Achilles tendon site, sex did not have a statistically significant effect on any compositional or material property in the low load‐bearing tendon fascicles of the tail. These data support recent studies by others, which suggest that male and female tendons have a differential adaptational response to their local mechanical loading environment. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:631–638, 2010     

Residual substance P levels after capsaicin treatment correlate with tendon repair

The aim of the study was to assess healing after capsaicin‐induced substance P (SP) depletion during rat Achilles tendon repair by biomechanical testing. Capsaicin treatment reduced the concentrations of SP by ～60% and calcitonin gene‐related peptide by ～40% as compared with the control group, as assessed by radioimmunoassay in the dorsal root ganglia, at 1 and 4 weeks post‐tendon rupture. Also, the peripheral neuronal presence of SP and calcitonin gene‐related peptide, as assessed by immunohistochemistry, was lower at both weeks 1 and 4. The decreased peripheral neuronal presence of SP at week 1 correlated with the corresponding levels in the dorsal root ganglia (r = 0.54, p = 0.018). The reduced presence of SP/calcitonin gene‐related peptide after capsaicin treatment was verified by a decreased sensitivity to painful mechanical and thermal stimuli (p < 0.05). Correlation analyses between individual residual SP levels and biomechanical tissue properties were performed because of differences in failure mode between the groups and high individual variations in the SP levels after capsaicin treatment. Thus, the residual SP levels in the dorsal root ganglia correlated with transverse area, ultimate tensile strength, and stress at failure (r = 0.39, p = 0.036; r = 0.53, p = 0.005; and r = 0.43, p = 0.023, respectively). Furthermore, individual pain sensitivity at week 2 correlated with peripheral occurrence of SP and was correlated with tensile strength and stress at failure (r = 0.89, p = 0.006 and r = 0.78, p = 0.015) at week 4. In conclusion, rats with higher residual SP levels after capsaicin‐induced neuropathy develop improved tensile strength and stress at failure in the healing of Achilles tendon.     

双小切口手术修复急性闭合性跟腱断裂

目的:评价手术治疗急性闭合性跟腱断裂的切口新方案.方法:自2009年1月至2014年1月采用保留跟腱断端皮桥、2个微创切口手术治疗急性跟腱断裂21例,男16例,女5例;年龄21~57岁,平均44.3岁.观察术后并发症,测量术后1年踝关节运动范围、双侧小腿最大周径、跟腱断裂平面周径、恢复工作及伤前体育活动的时间,采用美国足与踝关节协会(AOFAS)踝与后足功能评分方法进行评分.结果:21例均获随访,时间6~36个月,平均14个月.切口均Ⅰ期愈合,无皮肤坏死、切口感染、深静脉血栓、再断裂等并发症,腓肠神经支配区皮肤感觉正常.术后1年AOFAS评分94.3±5.5较术前65.1±6.9提高(t=7.672,P=0.013);患足踝关节活动范围(55.4±6.5)°与健足(56.3±3.7)°差异无统计学意义(t=0.872,P=0.325).21例均恢复伤前工作与学习,恢复工作时间平均10周(6~15周);15例恢复伤前体育活动,恢复伤前体育活动时间平均21周(18~24周).小腿最大周径伤侧较对侧平均减少0.45 cm(0.3~0.8 cm),跟腱断裂平面周径伤侧较对侧平均增粗0.4 cm(0.2~0.7 cm).结论:采用2个微创切口技术保存跟腱及其断端皮桥区软组织血液供应,并发症少.     

三种手术方法治疗新鲜跟腱断裂比较研究

目的比较传统切开跟腱吻合术、经皮微创跟腱吻合术以及应用跟腱吻合器有限切开术治疗新鲜闭合性跟腱断裂的疗效,为临床治疗方式的选择提供参考依据。方法 2007年12月-2010年3月将69例符合纳入标准的新鲜闭合性跟腱断裂患者随机分为3组,其中采用传统切开跟腱吻合术23例(传统切开组),经皮微创跟腱吻合术23例(经皮微创组),应用跟腱吻合器有限切开治疗23例(有限切开组)。3组患者性别、年龄、损伤机制、美国足踝外科协会(AOFAS)踝-后足评分等一般资料比较,差异均无统计学意义(P>0.05),具有可比性。结果经皮微创组及有限切开组住院时间及失血量明显优于传统切开组(P<0.01)。术后传统切开组发生2例(8.7%)切口感染坏死,其余两组患者切口均Ⅰ期愈合;传统切开组术后腱旁组织并发症发生率高于其余两组(P<0.05)。经皮微创组及有限切开组各1例(4.3%)发生跟腱再断裂,传统切开组跟腱再断裂发生率(0)低于其余两组(P<0.05)。69例均获随访,随访时间12～18个月,平均14.9个月。术后12个月3组踝关节AOFAS评分均>90分,较同组术前显著改善(P<0.05),组间比较差异无统计学意义(P>0.05)。结论 3种手术方式均能有效治疗新鲜跟腱断裂,有限切开或经皮微创手术方法创伤小,伤口愈合好,住院时间少,术后腱旁组织并发症少,但跟腱再断裂风险增加。     

Effects of low-voltage microamperage stimulation on tendon healing in rats

STUDY DESIGN: Randomized controlled prospective experimental study. OBJECTIVES: To examine the effects of transcutaneous low-voltage microamperage stimulation (LVMAS) on the mechanical strength of Achilles tendon repair in rats at 4 weeks after injury. BACKGROUND: Understanding the effect of LVMAS on the healing of injured tendons is hampered by the lack of related experimental studies, especially from the aspect of biomechanical outcome measures. METHODS AND MEASURES: Fourteen 3-month-old male Sprague-Dawley rats received surgical transection to the medial portion of their right Achilles tendon. The rats were divided into a LVMAS group (n = 7) and control group (n = 7). From day 6 postsurgery onwards, the LVMAS group received daily treatment of transcutaneous LVMAS (2.5 V, 100 microA/cm2, 10 pulses per second, positive current) for a total of 22 sessions, while the control group received placebo LVMAS by the same investigator during that period. On day 31, the Achilles tendons were harvested for biomechanical testing for load relaxation, stiffness, and ultimate tensile strength along the longitudinal direction. RESULTS: The normalized Achilles tendon ultimate tensile strength of the LVMAS group (mean +/- SD, 110.5% +/- 25.0%) was higher than that of the control group (75.3% +/- 20.8%) (P = .014), but no significant difference was found in normalized stiffness and load relaxation between the 2 groups (P = .239 and .350, respectively). CONCLUSION: The results of this study suggest that the administration of transcutaneous LVMAS could improve healing and consequently the tensile strength of partially transected Achilles tendons of rats at 4 weeks after injury.     

塑型卵圆钳经皮缝合与切开缝合治疗新鲜闭合性跟腱断裂的对照研究

目的 比较塑型卵圆钳经皮微创缝合技术和切开缝合技术治疗新鲜闭合性跟腱断裂的临床疗效。方法 回顾性研究自2014年1月至2016年10月收治的73例新鲜闭合性跟腱断裂病人,最终入组共70例,根据手术方式的不同分为两组：微创组（36例）借助自制的塑型卵圆钳,通过小切口经皮缝合修复跟腱;常规组（34例）采用常规跟腱内侧纵行切口,连续锁边缝合修复跟腱。记录两组手术时间、术中出血量、术后并发症、恢复至伤前运动水平的时间、末次随访时的美国足踝外科医师协会（American Orthopedic Foot and Ankle Society, AOFAS）踝与后足功能评分,术后1年复查MRI评估跟腱修复状况。结果 两组病人获得16~44个月（平均30个月）随访,其中微创组手术时间为（45.34±6.73） min,术中出血量为（15.12±4.11） ml;常规组手术时间为（69.33±13.44） min,术中出血量为（25.47±7.19） ml,两组比较,差异均有统计学意义（P均＜0.05）。微创组2例病人切口延迟愈合,2例出现线结刺激症状,1例腓肠神经损伤,1例于术后半年外伤后再断裂;常规组3例伤口浅表感染,2例出现深部感染,无腓肠神经损伤及跟腱再断裂。末次随访AOFAS评分：微创组为（95.81±2.35）分,常规组为（93.61±4.83）分;微创组有29例病人（21.0±4.7）周（20~24周）恢复至伤前运动水平,常规组有26例（23.0±3.5）周（21~31周）恢复至伤前运动水平;上述指标比较,差异均无统计学意义（P均＞0.05）。术后1年MRI均显示跟腱连续性完整,未观察到跟腱囊性变。结论 自制塑型卵圆钳经皮缝合技术修复新鲜闭合性跟腱断裂手术时间短,术后恢复更快,且并不增加跟腱再断裂发生率。     

Comparison of static and dynamic splinting regimens for extensor tendon repairs in zones V to VII

Abstract

The aim of this prospective, randomised, controlled trail was to compare two methods of rehabilitating extensor tendon repairs in zones V–VII. Patients who incurred simple and complete lacerations of their extensor tendons in zones V–VII enrolled into the study and underwent either static splinting (n = 25) or dynamic splinting (n = 27) after primary acute repair of tendons. Extension lag, flexion deficit, total active motion (TAM), grip strength, and functional status of upper extremities were measured. TAM was improved in the dynamic group when compared with the static group in the injured digits at 4 weeks (p = 0.001), at 12 weeks (p = 0.05), and at 6 months (p = 0.001). Grip strength outcomes demonstrated improved grip force for the dynamic group when compared with the static group at 12 weeks (p = 0.001). There were no ruptures in either group. Also, a better functional level was found in the dynamic splinting group at 6 months (p = 0.001). The findings of the current study suggest that dynamic splinting of complex lacerations of the extensor tendons in zones V–VII provides improved functional outcomes at 4 and 12 weeks and 6 months when compared with static splinting.     

Prospective randomized clinical trial of aggressive rehabilitation after acute Achilles tendon ruptures repaired with Dresden technique

BackgroundRupture of the Achilles tendon is a common injury during working years. Aggressive rehabilitation may provide better outcomes, but also a greater chance of re-rupture.ObjectiveTo determine if aggressive rehabilitation has better clinical outcomes for Achilles tendon function, Triceps surae function, one-leg heel rise capacity and lower complication rate during twelve weeks after percutaneous Achilles tendon repair compared to conventional rehabilitation.DesignRandomized controlled trial.MethodThirty-nine patients were prospectively randomized. The aggressive group (n = 20, 41.4 ± 8.3 years) received rehabilitation from the first day after surgery. The conventional group (n = 19, 41.7 ± 10.7 years) rested for 28 days, before rehabilitation started. The statistical parameters were the Achilles tendon rupture score (ATRS), verbal pain scale, time to return to work, pain medication consumption, Achilles tendon strength, dorsiflexion range of motion (RoM), injured-leg calf circumference, calf circumference difference, one-leg heel rise repetition and difference, re-rupture rate, strength deficit rate, and other complication rates. Mixed-ANOVA and Bonferroni's post hoc test were performed for multiple comparisons. Student's t-test was performed for parameters measured on the 12th week.ResultsThe aggressive group with respect to the conventional group had a higher ATRS; lower verbal pain score; lower pain medication consumption; early return to work; higher Achilles tendon strength; higher one-leg heel rise repetitions; and lower one-leg heel rise difference. The re-rupture rate was 5% and 5%, the strength deficit rate was 42% and 5%, and other complications rate was 11% and 15% in the conventional and aggressive group, respectively.ConclusionPatients with Dresden repair and aggressive rehabilitation have better clinical outcomes, Achilles tendon function and one-leg heel rise capacity without increasing the postoperative complications rate after 12 weeks compared to rehabilitation with immobilization and non-weight-bearing during the first 28 days after surgery.     

Treatment outcome at 1 year did not differ between use of cast or walker in the first 3 weeks after an acute Achilles tendon rupture. A registry study of 1304 patients from the Danish Achilles tendon database

BackgroundThe best choice of orthosis in the treatment of acute Achilles tendon rupture is still under debate.ObjectiveTo investigate if choice of orthosis in the first 3 weeks of treatment affected patient reported outcome (Achilles tendon Total Rupture Score (ATRS)), tendon elongation (Achilles Tendon Resting Angle (ATRA) and Heel Rise Height (HRH)) and re-rupture.MethodsRegistry study in the Danish Achilles tendon Database. Patients treated with cast and patients treated with walker in the first 3 weeks of treatment were compared using a linear mixed-effects model adjusted for potential confounders.Results1304 patients were included in the study. No clinically relevant difference was found: Adjusted mean difference (using walker the whole period as reference)(95% CI) ATRS after 1 year = 0.1(?3.0; 4.1), ATRS after 6 months = 2.0(?4.5; 5.8), ATRS after 2 years = 3.0(?0.7; 7.0), HRH difference = 0.6(?6.6; 8.2), ATRA difference = 0.03°(?1.5; 1.6), re-rupture(odds ratio) = 0.812(0.4; 1.61).ConclusionPatients treated with cast the first 3 weeks after acute Achilles tendon rupture did not have better treatment outcome than patients treated with walker.     

跟腱断裂术后即刻功能锻炼的临床研究

目的:通过与跟腱断裂术后2周进行功能锻炼及下地部分负重行走的比较,探讨跟腱断裂术后即刻功能锻炼及下地部分负重行走对患肢功能及跟腱再断裂的影响。方法:将2012年3月至2013年3月收治的64例闭合性跟腱断裂手术患者分为两。治疗组34例,男18例,女16例;年龄(41.4±7.6)岁;于术后第2天即行功能锻炼及佩戴支具下地部分负重行走。对照组30例,男16例,女14例;年龄(39.9±7.6)岁;术后予患肢短腿石膏跖屈位固定2周,2周后行功能锻炼及佩戴支具下地部分负重行走。两组患者由同一组医生采用相同的手术方式处理,观察并比较两组患者AOFAS踝关节功能评分、跟腱再断裂及伤口并发症情况。结果 :术后2个月AOFAS评分治疗组74.3±3.9,对照组71.7±4.2,治疗组高于对照组;术后1年治疗组93.3±3.9,对照组92.0±4.1,两组比较差异无统计学意义。术后治疗组无跟腱再断裂,对照组1例发生跟腱再断裂;术后治疗组2例发生伤口并发症,对照组1例发生并发症,差异无统计学意义。结论:跟腱断裂术后患者即刻功能锻炼,踝关节AOFAS功能评分优于固定2周后再行功能锻炼,同时不增加术后跟腱再断裂率及并发症发生率,有利于患肢功能恢复。     

Mechanical evaluation of different techniques for Achilles tendon repair

Introduction One aim of the surgical treatment of acute Achilles tendon ruptures is to obtain a maximum primary stability of the sutured tendon. Therefore, we investigated the primary stability of sutured human Achilles tendons depending on different applied techniques. Methods The strength of 60 repaired cadaveric human Achilles tendons was tested depending on either the suture technique (Bunnell or Kessler), the suture material (PDS-thread or PDS-cord) or an additional plantaris tendon augmentation (PDS-thread with or without augmentation). Following anatomic reconstruction the repaired specimens were loaded to failure. Results The use of Bunnell's technique resulted in a stronger primary suture stability compared to Kessler's technique. Sutures carried out with a PDS-thread were of lower strength than those accomplished with a PDS-cord (Bunnell: thread 139 N ± 29.8; cord 291 N ± 55.2/Kessler: thread 137 N ± 37.3; cord 180 N ± 41.1). Sutures performed according to Bunnell's technique with a PDS-thread and an additional autologous plantaris tendon augmentation reached the highest primary stability (326 N ± 124.9). Conclusions The findings identify the Achilles tendon suture with a PDS-cord according to Bunnell's technique as a mechanically strong method. A plantaris tendon augmentation in addition to a PDS-thread can even add more stability to the Achilles tendon suture.     

Diabetes mellitus alters the mechanical properties of the native tendon in an experimental rat model

The purpose of this study was to determine the effect of the diabetic phenotype on the mechanical properties of the native patellar tendon and its enthesis. Diabetes was induced via intraperitoneal injection of streptozotocin in Lewis rats. Control (n = 18) and diabetic animals (n = 20) were killed at 12 and 19 days for analysis. Statistical comparisons were performed using Student's t‐tests and a two‐tailed Fisher test with significance set at p < 0.05. Pre‐ and post‐injection intraperitoneal glucose tolerance tests demonstrated significant impairment of glycemic control in the diabetic compared to control animals (p = 0.001). Mean serum hemoglobin A1c levels at 19 days was 10.6 ± 2.7% and 6.0 ± 1.0% for the diabetic and control groups, respectively (p = 0.0001). Fifteen of sixteen diabetic animals demonstrated intrasubstance failure of the patellar tendon, while only 7 of 14 control specimens failed within the tendon substance. The Young's modulus of the diabetic tendon was significantly lower than control specimens by 19 days post‐induction (161 ± 10 N m^?2 compared to 200 ± 46 N m^?2, respectively) (p = 0.02). The metabolic condition of poorly controlled diabetes negatively affects the mechanical properties of the native patellar tendon. These altered structural properties may predispose diabetic patients to a greater risk of tendinopathy and/or traumatic rupture. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:880–885     

Sodium cromolyn reduces expression of CTGF,ADAMTS1, and TIMP3 and modulates post‐injury patellar tendon morphology

The purpose of this study was to determine whether administration of a mast cell inhibitor (sodium cromolyn, SC) would influence tendon repair and extracellular matrix gene expression following acute injury. CD1 mouse patellar tendons were unilaterally injured and mast cell prevalence was determined. The effect of SC injection on tendon hypercellularity, cross‐sectional area, collagen organization, and expression of extracellular matrix‐related genes was examined. Mast cell prevalence was markedly increased in injured patellar tendons (p = 0.009), especially at 8 weeks post‐injury (p = 0.025). SC injection increased collagen organization compared to uninjected animals at 4 weeks and attenuated the development of tendon hypercellularity and tendon thickening post‐injury. Expression of CTGF, ADAMTS1, and TIMP3 in injured tendon was reduced in the SC group. SC injections moderated the structural alterations of healing tendon in association with downregulation of several genes associated with tendon fibrosis. This work corroborates previous findings pointing to a role of mast cells in tendon repair. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:678–683, 2011