Biomechanical Study of a Multifilament Stainless Steel Cable Crimp System Versus a Multistrand Ultra-High Molecular Weight Polyethylene Polyester Suture Krackow Technique for Achilles Tendon Rupture Repair

Currently, Achilles tendon rupture repair is surgically addressed with an open or minimally invasive approach using a heavy, nonabsorbable suture in a locking stitch configuration. However, these sutures have low stiffness and a propensity to stretch, which can result in gapping at the repair site. Our study compares a new multifilament stainless steel cable-crimp repair method to a standard Krackow repair using multistrand, ultra-high molecular weight polyethylene polyester sutures. Eight matched pairs of cadavers were randomly assigned for Achilles tendon repair using either Krackow technique with polyethylene polyester sutures or the multifilament stainless steel cable-crimp technique. Each repair was cyclically loaded from 10 to 50 N for 100 loading cycles, followed by a linear increase in load until complete failure of the repair. During cyclic loading, 4 of the 8 Krackow polyethylene polyester suture repairs failed, whereas none of the multifilament stainless steel cable crimp repairs failed. Load to failure was greater for the multifilament stainless steel cable crimp repairs (321.03 ± 118.71 N) than for the Krackow polyethylene polyester suture repairs (132.47 ± 103.39 N, p = .0078). The ultimate tensile strength of the multifilament stainless steel cable crimp repairs was also greater than that of the Krackow polyethylene polyester suture repairs (485.69 ± 47.93 N vs 378.71 ± 107.23 N, respectively, p = .12). The mode of failure was by suture breakage at the crimp for all cable-crimp repairs and by suture breakage at the knot, within the tendon, or suture pullout for the polyethylene polyester suture repairs. The multifilament stainless steel cable crimp construct may be a better alternative for Achilles tendon rupture repairs.     

Management of Acute Achilles Tendon Rupture Using the Krackow and Tendon-Bundle Techniques

Background Acute Achilles tendon rupture is a severe injury of the lower extremities;however,optimal treatment options are not yet available.This study aimed to investigate the surgical method and clinical effect of the Krackow and tendon-bundle techniques for managing acute Achilles tendon rupture.Methods This retrospective case series study analyzed 17 cases of acute Achilles tendon rupture at the Beijing Jishuitan Hospital from December 2012 to January 2020.There were 16 men and one woman,aged 27–45 years,with an average of 39.6 years.Thirteen patients were injured while playing basketball or badminton,and 4 patients were injured while participating in a football match or other sports.All injuries were repaired using the Krackow and tendon-bundle techniques.Postoperative evaluation indicators included active range of motion during ankle plantar flexion and dorsiflexion,height of single foot heel lifting,Amer-Lindholm Achilles tendon function score,and American Orthopedic Foot and Ankle Society(AOFAS)score.Results The patients were followed-up for 6–45 months(average,18.9 months).There was no re-rupture of the Achilles tendon,wound infection,or sural nerve injury.At the final follow-up,the affected and contralateral sides exhibited plantar flexion of 42.1±4.4°and 43.8±2.8°,dorsiflexion of 15.8±2.9°and 16.6±2.9°,respectively,and one foot exhibited a heel lifting height of 7.2±1.0 cm and 7.5±0.9 cm,respectively.There was no significant difference between the affected and contralateral sides(P>0.05).At the final follow-up,the Amer-Lindholm Achilles tendon function score was excellent in 94.1%(16/17)of the patients and good in 5.9%(1/17)of the patients.The AOFAS scores ranged from 90 to 100,with an average of 96.4±3.7.Conclusion Krackow and tendon-bundle techniques can improve the strength of the suture used for the Achilles tendon repair and ensure good matching for broken ends,and thus it is an effective repair method for closed Achilles tendon injury.     

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.     

A novel repair method for the treatment of acute Achilles tendon rupture with minimally invasive approach using button implant: A biomechanical study

BackgroundMinimally invasive Q3 repair has been proposed for acute Achilles tendon rupture with low rate of complications. However there are still controversies about optimal technique. In this study we aimed to describe Endobutton-assisted modified Bunnell configuration as a new Achilles tendon repair technique and evaluate its biomechanical properties comparing with native tendon and Krackow technique.Methods27 ovine Achilles tendons were obtained and randomly placed into 3 groups with 9 specimens ineach. The Achilles tendons were repaired with Endobutton-assisted modified Bunnell technique in group 1, Krackow suture technique in group 2 and group 3 was defined as the control group including native tendons. Unidirectional tensile loading to failure was performed at 25 mm/min. Biomechanicalproperties such as peak force to failure (N), stress at peak (MPa), elongation at failure, and Young'smodulus (GPa) was measured for each group. All groups were compared with each other using one-wayANOVA followed by the Tukey HSD multiple comparison test (a = 0.05).ResultsThe average peak force (N) to failure of group 1 and group 2 and control group was 415.6 ± 57.6, 268.1 ± 65.2 and 704.5 ± 85.8, respectively. There was no statistically significant difference between native tendon and group 1 for the amount elongation at failure (p > 0.05).ConclusionsRegarding the results, we concluded that Endobutton-assisted modified Bunnell technique provides stronger fixation than conventional techniques. It may allow early range of motion and can be easily applied in minimally invasive and percutaneous methods particularly for cases with poor quality tendon at the distal part of rupture.Level of evidenceLevel II, Biomechanical research study.     

Evaluation of a New Knotless Suture Anchor Repair in Acute Achilles Tendon Ruptures: A Biomechanical Comparison of Three Techniques

Acute ruptures of the Achilles tendon are a common injury, and debate has continued in published studies on how best to treat these injuries. Specifically, controversy exists regarding the surgical approaches for Achilles tendon repair when one considers percutaneous versus open repair. The present study investigated the biomechanical strength of 3 different techniques for Achilles tendon repair in a cadaveric model. A total of 36 specimens were divided into 3 groups, each of which received a different construct. The first group received a traditional Krackow suture repair, the second group was repaired using a jig-assisted percutaneous suture, and the third group received a repair using a jig-assisted percutaneous repair modified with suture anchors placed into the calcaneus. The specimens were tested with cyclical loading and to ultimate failure. Cyclical loading showed a trend toward a stronger repair with the use of suture anchors after 10 cycles (p = .295), 500 cycles (p = .120), and 1000 cycles (p = .040). The ultimate load to failure was greatest in the group repaired with the modified knotless technique using the suture anchors (p = .098). The results of the present study show a clear trend toward a stronger construct in Achilles repair using a knotless suture anchor technique, which might translate to a faster return to activity and be more resistant to an early and aggressive rehabilitation protocol. Further clinical studies are warranted to evaluate this technique in a patient population.     

Achilles Tendon Open Surgical Treatment With Platelet-Rich Fibrin Matrix Augmentation: Biomechanical Evaluation

The relationship between surgical technique and ankle biomechanical properties after surgery for acute rupture of the Achilles tendon (ATR) has not yet been fully investigated. Platelet-rich fibrin (PRF) matrices seem to play a central role in the complex processes of tendon healing. Our aim was to analyze the biomechanical characteristics, stiffness, and mechanical work of the ankle during walking in patients who had undergone surgery after ATR with and without PRF augmentation. We performed a retrospective review of all consecutive patients who had been treated with surgical repair after ATR. Of the 20 male subjects enrolled, 9 (45%) had undergone conventional open repair of the Achilles tendon using the Krackow technique (no-PRF) and 11 (55%) had undergone surgery with PRF augmentation. An additional 8 healthy subjects were included as a control group. A gait analysis evaluation was performed at 6 months after surgery. The percentage of the stance time of the operated leg, double-support time of the healthy leg, and net work of the ankle during the gait cycle showed statistically significant differences between the no-PRF and the healthy group (p < .005). No differences were found between the PRF and healthy groups. Treatment with suture and PRF augmentation could result in significant functional improvements in term of efficiency of motion.     

Treatment of acute achilles tendon rupture with the panda rope bridge technique

IntroductionAlthough nonsurgical methods and many surgical techniques have been developed for repairing a ruptured Achilles tendon, there is no consensus on its best treatment. In this article, a novel minimally invasive technique called the Panda Rope Bridge Technique (PRBT) is described.MethodsPatient with acute Achilles tendon rupture was operated on in the prone position. The PRBT begin with making the proximal bridge anchor (Krackow sutures in the myotendinous junction), the distal bridge anchor (two suture anchors in the calcaneus bone) and the ropes (threads of the suture anchors) stretched between the anchor sites. Then a small incision was made to debride and reattach the stumps of ruptured tendon. After the surgery, no cast or splint fixation was applied. All patients performed enhanced recovery after surgery (ERAS), which included immediate ankle mobilisation from day 1, full weight-bearing walking from day 5 to 7, and gradually take part in athletic exercises from 8 weeks postoperatively.ResultsPBRT was performed in 11patients with acute Achilles tendon rupture between June 2012 and June 2015. No wound infection, fistula, skin necrosis, sural nerve damage, deep venous thrombosis or tendon re-rupture was found. One year after the surgery, all patients reported 100 AOFAS ankle-hindfoot score points and the mean ATRS was 96.6.ConclusionThe PRBT is a simple, effective and minimally invasive technique, with no need for immobilisation of the ankle, making possible immediate and aggressive postoperative rehabilitation.     

Biomechanical Comparison of Tape Versus Suture in Simulated Achilles Tendon Midsubstance Rupture

As sutures have progressed in strength, increasing evidence supports the suture tendon interface as the site where most tendon repairs fail. We hypothesized that suture tape would have a higher load to failure versus polyblend suture due to its larger surface area. Eleven matched pairs of cadaveric Achilles tendons were sutured with 2 mm wide braided ultrahigh molecular weight polyethylene tape (Tape) or 2 mm wide braided ultrahigh molecular weight polyethylene suture (Suture) using a Krackow repair method. All Achilles repair constructs were cyclically loaded, after which they were loaded to failure. Change in suture footprint height, clinical and ultimate load to failure, and location of failure was recorded. Clinical loads to failure for Tape and Suture were 290.4 ± 74.8 and 231.7 ± 70.4 Newtons, respectively (p= .01). Ultimate loads to failure for Tape and Suture were 352.9 ± 108.1 and 289.8 ± 53.7 Newtons, respectively (p = .11). Cyclic testing resulted in significant changes in footprint height for both Tape and Suture, but the 2 sutures did not differ in terms of the magnitude of change in footprint height (p = .52). The suture tendon interface was the most common site of failure for both Tape and Suture. Our results suggest that Tape may provide added repair strength in vivo for Achilles midsubstance rupture.     

Strength of Different Krackow Stitch Configurations Using High-strength Suture

The purpose of the present study concerning high-strength sutures was to determine whether increasing the number of locking loops with different size sutures or decreasing the suture size with increased suture strands would have any influence on the strength of Achilles tendon repair. A total of 32 fresh bovine Achilles tendon specimens were randomly assigned to 4 groups. For 3 of the groups, 1 suture was used (no. 2 or no. 5 FiberWire? with 2 or 4 Krackow locking loops). For the fourth group, 2 sutures (2-0 FiberWire?) with 2 locking loops were used. After repair, the study groups underwent cyclic loading (0 to 200 N, 200 cycles) and then underwent tension to failure in a testing machine. Cyclic elongation, peak to peak displacement, ultimate load, stiffness, and failure mode were recorded for each specimen. The tendon width and thickness were measured in all specimens. The mean width, thickness, cyclic displacement, load to failure, and pull-out stiffness showed no differences among the 4 groups. The cyclic peak to peak displacements (0.01 ± 0.01 mm) were smallest with the no. 5 suture with 4 locking loops (p < .05), with no failure during cyclic loading, unlike in the other groups. In the group with 2-0 suture with 4 strands and 2 locking loops, 6 failed during cyclic loading. The number of locking loops used might have had an influence on the strength of the Krackow suture configuration using the larger diameter, high-strength sutures. However, decreasing the suture diameter, with a simultaneous increase in the number of strands, failed to improve the initial strength of the repair.     

Comparison of Four Methods for Percutaneous Achilles Tendon Lengthening: A Cadaveric Study

Percutaneous Achilles tendon lengthening can result in Achilles tendon rupture. This complication has been controversially linked to torsion effects in the Achilles tendon. Routine percutaneous triple-hemisection techniques (group A), rotary triple-hemisection (group B), distal double-hemisection (group C), and proximal double-hemisection (group D) were compared in cadaveric specimens to provide insights into the mechanism of uneven incision lengthening and inadvertent Achilles tendon rupture. The degree of Achilles tendon torsion on various planes was measured in 20 lower limb pairs from fresh cadavers. The increase in postoperative maximum ankle joint dorsiflexion degree and the length of the lengthened Achilles tendon were greater in group B (p < .05) and group C (p < .05) compared with the routine percutaneous triple-hemisection technique (group A). The width of the tensile gap of the distal incision was significantly greater in group B (p < .05) and group C (p < .05) compared with that in group A. Rotary triple-hemisection was shown to eliminate the effect of Achilles tendon torsion on percutaneous Achilles tendon lengthening. Because proximal double-hemisection is performed away from the distal Achilles tendon where the fibers rotate sharply, the technique results in more even extension of the incisions and achieves a greater increase in the maximum degree of ankle joint dorsiflexion. Uneven incision lengthening was observed with the routine percutaneous triple-hemisection and distal double-hemisection techniques. Achilles tendon torsion affected the surgical outcomes. Rotary triple-hemisection and proximal double-hemisection techniques resulted in more even extension of the incisions and achieved a greater increase in the degree of maximum ankle joint dorsiflexion.     

Rates of complications in Achilles tendon rupture repair using absorbable and nonabsorbable suture material; A systematic review

BackgroundThe impact of suture type on tensile strength, re-rupture rates and infection risk in Achilles tendon rupture repair is not been well established. The aim of this review is to evaluate existing literature on the associated risk of postoperative infection with absorbable and non-absorbable suture materials in Achilles tendon rupture repair.MethodsA systematic review of search databases PubMed; Google Scholar; and OVID Medline was made to identify studies related to complications associated with Achilles tendon rupture repair. PRISMA guidelines were utilised for this review. Meta-analysis was used to compare rupture rates and infections following rupture repair.Results12 studies with a total of 460 patients, 230 in both nonabsorbable and absorbable suture groups were included for analysis. Risk of wound complications was significantly higher in patients with non-absorbable sutures (p < 0.001).ConclusionNonabsorbable braided sutures is associated with the highest risk of postoperative wound complications following Achilles tendon rupture repair.     

Severe Functional Debilitations After Complications Associated With Acute Achilles Tendon Rupture With 9 Years of Follow-Up

The purpose of the present study was to investigate the long-term effect of deep infection, sural nerve injury, and repeat rupture in the treatment of acute Achilles tendon rupture. A total of 324 patients had made a claim to the Danish Patient Insurance Association from 1992 to 2010 for a complication after acute Achilles tendon rupture. Of the 324 patients, 119 (36.7%) (77 [64.7%] males and 42 [35.3%] females) returned the Achilles tendon total rupture score and the 36-item short-form survey questionnaires. Patients with deep infection (n = 10), sural nerve injury (n = 10), and repeat rupture (n = 16) participated in a follow-up investigation. The mean follow-up period was 8.9 (range 3 to 21) years. The mean Achilles tendon total rupture score was 49 ± 27. The summary scores of the physical component and mental components scales of the 36-item Short Form Survey were 43 ± 11 and 52 ± 11, respectively. No significant differences were found among the subpopulations with deep infection, injury to the sural nerve, or repeat rupture. The physical evaluation investigating tendon length and heel rise work revealed a statistically significant difference between the affected and unaffected limb after repeat rupture (p < .01) but not after injury to the sural nerve (p > .05) or deep infection (p > .05). In conclusion, patients with from a complication after acute Achilles tendon rupture had a remarkable reduction of the Achilles tendon total rupture score and physical component scale score at mean follow-up point of 9 years. Patients with repeat rupture had a significant elongation of the tendon and reduction of strength in the affected limb.     

Biomechanical comparison of the primary stability of suturing Achilles tendon rupture: a cadaver study of Bunnell and Kessler techniques under cyclic loading conditions

Introduction  Biomechanical studies investigating suture techniques for Achilles tendon repair used single load to failure tests in order to evaluate the maximal load capacity of the repaired construct. During early rehabilitation the repair is repetitively loaded such as exercise or daily living activities like walking. Cyclic loading seems to duplicate the physiological loading conditions more closely than single cycle failure tests. Aim of this study was to test the most commonly used Achilles tendon repair techniques (Bunnell and Kessler repair) under cyclic loading conditions. Materials and methods  Following tenotomy fresh human cadaveric tendons were sutured either with the Bunnell or Kessler technique. After repair, cyclic loading tests were performed with a uniaxial biomechanical testing machine Lloyd LR-5K Plus. Both groups were sutured with 0.7 mm PDS. Results  Except at maximum load we could not find significant differences between tendons sutured by Bunnell and Kessler techniques. During the cyclic testing there were no differences between both groups with respect to displacement. This applies also to the stiffness of the constructs, which we defined from the load to failure measurements. The failure modes in both groups differed; the tendons repaired by Kessler technique were cut by the tendons and in the Bunnell group the suture material tore in each specimen tested. Conclusion  In our study Bunnell and Kessler techniques showed similar biomechanical properties using the same suture material. The typical failure mode of the Bunnell technique shows potential to optimise biomechanical behavior by using stronger suture material.     

Endoscopic-assisted repair of acute Achilles tendon rupture with Krackow suture: An anatomic study

PurposeTo study the feasibility of applying Krackow locking stitches in the endoscopic-assisted repair of acute Achilles tendon rupture and the possible complications encountered.Type of studyAnatomic study.MethodsTwelve Achilles tendons in six cadavers were cut at 6 cm from its insertion and endoscopic-assisted repair of Achilles tendon was performed. These legs were then cut open in midline to study (i) the locking stitches formed and (ii) the relation of the sural nerve to the locking stitches.ResultWith endoscopic-assisted technique, Krackow-type locking stitches can be formed in eight legs. In four legs, the stitches fell into the ruptured gap and lie deep to the tendon. The tendon rupture end was grasped by the suture rather than forming a Krackow-type locking stitch when the suture was tightened. There was no sural nerve laceration noted. However, in two legs, the sural nerves were found trapped in the sutures at around the proximal portal.ConclusionsKrackow locking stitches can be formed by the minimally invasive technique. However, there are risks of stitches falling into the ruptured gap and lie deep to the tendon and risk of sural nerve entrapment at the proximal medial portal. The original technique is not suitable for clinical application. Modification of the technique by grasping the tendon end with Allis tissue forceps before passing the suture may prevent the suture from falling into the ruptured tendon gap.     

Repair of Achilles Tendon Rupture Using Autologous Semitendinosus Graft in a Kidney Transplant Recipient

Insertional Achilles tendon injuries can be difficult to treat when minimal tendon tissue remains for anastomosis. Moreover, in the chronic case with tendon shortening, operative repair can be more difficult than acute rupture. It is particularly desirable to reinforce the tendons, in addition to performing primary repair, in patients with renal or systemic diseases because of the accelerated collagen degeneration. Many techniques have been described for the surgical management of Achilles tendon rupture; however, none has shown clear superiority. We report the case of a 50-year-old renal transplant patient with a spontaneous distal Achilles tendon injury that we repaired using the pull-out technique reinforced with an autologous semitendinosus graft. At 2 years postoperatively, the ankle-hindfoot scale score was 92 points, and the postoperative course was without complication. We believe that the free hamstring tendon autograft is advantageous for this repair, because it is easy to handle, has limited donor site morbidity, and preserves the structures around the ankle.     

Open Re-rupture of the Achilles Tendon Following Minimally Invasive Repair: A Case Report

In this report, we describe a rare complication of an open re-rupture of the Achilles tendon following a minimally invasive Achilles tendon repair on a healthy 29-year-old active male. The reinjury happened 19 weeks following the primary surgical repair of a spontaneous rupture, performed by minimally invasive technique with the help of a jig using partially absorbable sutures and four locking stitches. The wound of the open re-rupture was transverse, in a perpendicular orientation relative to the longitudinal approach used in the index procedure. Increased scar tissue formation, the absence of an adequate layer of paratenon overlying the primary tendon repair, and foreign-body reaction to the suture may have been involved in the occurrence of this unusual complication in the surgical treatment of Achilles tendon rupture.     

自制器械辅助微创手术治疗陈旧性跟腱断裂的疗效分析

目的观察应用自制器械辅助微创手术治疗陈旧性跟腱断裂的临床效果。方法回顾性分析自2017-05—2018-12应用自制器械辅助微创手术治疗的9例陈旧性跟腱断裂,术中将自制器械由卵圆孔端置入皮下组织与腱周组织间隙辅助改良Bunnell缝合法完成对跟腱断端缝合操作。末次随访时采用Arner-Lindholm评分标准对踝关节功能进行评价。结果本组手术时间(31.0±5.9)min,切口长度(3.5±0.6)cm。9例均获得随访,随访时间平均14.1(12~18)个月。术后1例出现切口皮缘部分坏死,经换药后愈合并于术后18 d拆线,其余患者切口均一期愈合。所有患者均无排异反应、腓肠神经损伤、下肢深静脉血栓形成等并发症发生。术后12个月随访时采用Arner-Lindholm评分标准评价踝关节功能:优6例,良2例,可1例。结论采用自制器械辅助微创手术治疗陈旧性跟腱断裂具有手术时间短、切口小、术后并发症少、踝关节功能恢复好等优点,临床疗效满意,值得推广应用。     

Biomechanical comparison of new Achilles tendon rupture repair technique the “Giftbox” versus the Krackow technique in New Zealand white rabbits: An experimental animal study

IntroductionTo compare the strength between the Achilles tendons repaired with the “Giftbox” and the Krackow techniques in New Zealand white rabbits post six weeks of tendon healing.Materials and MethodsEight rabbits were randomized into Giftbox and Krackow groups. Tenotomy was performed on the Achilles tendon of one side of the lower limb and repaired with the respective techniques. The contralateral limb served as control. Subjects were euthanized six weeks post-operative, and both repaired and control Achilles tendons were harvested for biomechanical tensile test.ResultsThe means of maximum load to rupture and tenacity in the Giftbox group (156.89 ± 38.49 N and 159.98 ± 39.25 gf/tex) were significantly different than Krackow's (103.55 ± 27.48 N and 104.91 ± 26.96 gf/tex, both p = 0.043).ConclusionThe tendons repaired with Giftbox technique were biomechanically stronger than those repaired with Krackow technique after six weeks of tendon healing.     

Initial Achilles tendon repair strength-synthesized biomechanical data from 196 cadaver repairs

Purpose

The study aim was to describe what kind of operative technique performs best with respect to initial strength after the surgical repair of acute Achilles tendon ruptures.

Methods

We performed a systematic search of the keywords “Achilles tendon AND (suture strength OR biomechanics) AND (cadaver NOT animal)” in the online databases PubMed, EMBASE, CINAHL, and the Cochrane Library. We included studies that employed open, mini-open, or percutaneous Achilles tendon repair in human cadavers, and assessed some measure of tensile strength as a primary outcome.

Results

Our search produced 11 relevant papers reporting results for Kessler, Bunnell, and Krackow sutures in open repair, as well as the Achillon device, the Ma-Griffith repair technique, the triple bundle technique and the “giftbox” technique. The weighted tensile strengths ranged from 81 to 453 N (mean 222.7 N) with the Triple Bundle technique in combination with # 2 Ethibond performing best with a mean of 453 N.

Conclusions

Due to the small sample sizes, different study designs, and heterogeneity of strength measurement techniques, definite recommendations on surgical technique cannot be made but presented information might help in the decision making process for foot and ankle surgeons.     

Spiral-shaped Metallic Implant in the Treatment of Achilles Tendon Ruptures: An Experimental Study on the Achilles Tendon of Sheep

There are 2 main factors contributing to the strength of tendon repair: the tensile strength of the material used in repair and the tendon-holding capacity of the suture configuration. In the current study, we aimed to find a technique with high repair strength by increasing both the tensile strength of the material and the tendon-holding capacity of the configuration. We developed metal implants (models 1 and 2) made from stainless-steel wire with 2 different spiral-shaped configurations. We measured tendon-holding capacities of these alternative implants biomechanically and compared them with frequently used suture techniques, the Bunnell and locking loop, which were achieved with 5 Ticron sutures. Sixty-four sheep Achilles' tendons were used in the study as 16 tendons in each group. Model 2 was more resistant to deformation under loading when compared with model 1. The results demonstrated that model 2 was superior to model 1 and both suture techniques. This study could be accepted as a step for reaching a strong tendon repair technique. It should be emphasized that the technique needs to be improved technically to make it convenient for clinical use.