Efficacy of repair techniques of the Achilles tendon: A meta-analysis of human cadaveric biomechanical studies

2-Octyl cyanoacrylate adjuvant use in calcaneal tendon repair: A comparative experimental study in rabbits

Purpose

The treatment of Achilles tendon (AT) rupture can be conservative or surgical; the latter is better indicated in high-performance athletes. The pursuit of faster recovery and reductions in skin complications and re-ruptures have improved the tendon repair technique and early assisted rehabilitation programs. Our goal was to check whether or not the adjuvant use of 2-octyl cyanoacrylate (CA) provides additional mechanical resistance to the calcaneal tenorrhaphy when compared to sutures alone.

Methods

In the study, 45 rabbits were used, and distributed into three groups of 15 animals each. They underwent two surgical procedures at a 30-day interval. In the first, a complete AT section was done on the right side and then was repaired using three different techniques: suture alone in Group 1, suture with 2-octyl CA in Group 2 and 2-octyl CA alone in Group 3. After 30 days, the rabbits were euthanized, and their right-side calcaneal tendon was resected, and sent the specimen for pathology analysis. Then, a cross-section of the left calcaneal tendon was performed, and the same three repair techniques were used. After 15 min, the repaired tendons to the linear traction mechanical strength test were done.

Results

The results from the linear strength test showed that suture with glue outperformed suture alone (p = 0.0427), and glue alone (p < 0.0001). The pathology results were evaluated according to inflammation, repair process and tendon thickness. The report mentioned a high-intensity mixed inflammatory pattern (acute and chronic), outstanding neovascularization, tissue necrosis and abscess in most of the cases that used CA. However, there were no local or systemic clinical signs of an infectious process.

Conclusions

2-octyl CA added immediate mechanical strength to the calcaneal tendon repair in the rabbits, without increasing local complications, despite pathological changes up to 30 days after the repair.

Level of Evidence

NA study.

Suture techniques in the surgical management of flexor tendon, Achilles tendon and cruciate ligament injuries: a systematic review

OBJECTIVE

To provide clinicians with reliable recommendations for the selection of appropriate suturing techniques for surgical management of common musculoskeletal soft tissue injuries.

METHODS

A systematic search of PubMed, Springer, Web Science, Vip Database, China National Knowledge, and Wanfang Data for in vitro biomechanical studies on suture techniques in the surgical treatment of musculoskeletal soft tissue injuries covering relevant studies from April 2009 to April 2024 was performed. A generalized classification was made based on the characteristics of the techniques, and recommendations for the selection of suture techniques were made according to the GRADE concept.

RESULTS

The search strategy returned 1015 articles, of which 66 were included. These studies presented moderate and high levels of evidence-based evidence and provided varying recommendations for the choice of suturing techniques in the treatment of three common musculoskeletal soft tissue injuries. Categorizing suturing techniques according to their structural principles further increases the reliability of opinions.

CONCLUSION

The ideal suture technique must be a compromise between the complexity and strength of the repair, which is a great challenge for clinicians. This review can provide an objective and reliable clinical guide for making suture technique choices for common musculoskeletal soft tissue repair.

All-inside endoscopic semiautomatic running locked stitch technique shows favourable outcomes for acute Achilles tendon ruptures

PURPOSE

The safety and reliability of endoscopic Achilles tendon rupture repair are still concerning aspects. This study's aim is to evaluate an all-inside endoscopic semiautomatic running locked stitch (Endo-SARLS) technique.

METHODS

Forty cases with acute Achilles tendon rupture were treated with the all-inside Endo-SARLS technique between 2020 and 2021. Under endoscopic control, the proximal tendon stumps were stitched with the running locked method using a semiautomatic flexible suture passer. The threads of the high-strength suture were grasped through the paratenon subspace and then fixed into calcaneal insertion with a knotless anchor. Magnetic resonance imaging (MRI), surgical time and complications were assessed. Achilles Tendon Total Rupture Score (ATRS), Achilles Tendon Resting Angle (ATRA) and Heel Rise Height Scale (HRHS) were utilised to evaluate final outcomes.

RESULTS

The average follow-up time was 25.4 ± 0.4 (range: 24-32) months. Appropriate tendon regeneration was observed on MRI after 12 months. At the final follow-up, the median value of ATRS score was 95 (interquartile range: 94, 98). Furthermore, there is no significant difference between the injured and contralateral side in the average ATRA (18.2 ± 1.8 vs. 18.3 ± 1.9°, ns) and median value of HRHS [14.5 (13.3, 15.5) vs. 14.8 (13.5, 15.6) cm, ns]. No infection and nerve injuries were encountered. Thirty-nine patients reported that they resumed casual sports activity after 6 months. One patient had a slight anchor cut-out, due to an addition injury, which was removed after 5 months.

CONCLUSIONS

An all-inside Endo-SARLS technique showed promising clinical results for acute Achilles tendon ruptures. This procedure reduces the risk of sural nerve injuries while establishing a reliable connection between the tendon stumps.

LEVEL OF EVIDENCE

Level IV.

No difference in operative time, outcomes, cosmesis, or return to activity and/or sport after minimally invasive versus open repair of primary Achilles ruptures: a retrospective review

PURPOSE

To compare clinical outcomes and the rate of return to sport among patients that have undergone minimally invasive repair versus open approach of an acute Achilles tendon rupture.

METHODS

Patients who underwent surgical repair of acute Achilles tendon rupture at a single urban academic institution from 2017 to 2020 with minimum 2-year follow-up were reviewed retrospectively. Preinjury sport participation and preinjury work activity information, the Achilles tendon Total Rupture Score (ATRS), the Tegner Activity Scale, Patient-Reported Outcomes Measurement Information System for mobility and pain interference were collected.

RESULTS

In total, 144 patients were initially included in the study. Of these, 63 patients were followed with a mean follow-up of 45.3 ± 29.2 months. The mean operative time did not significantly differ between groups (p = 0.938). Patients who underwent minimally invasive repair returned to sport at a rate of 88.9% at a mean of 10.6 ± 5.8 months, compared to return rate of open procedures of 83.7% at 9.5 ± 5.5 months. There were no significant differences in ATRS (p = 0.246), Tegner (p = 0.137) or VAS pain (p = 0.317) scores between groups. There was no difference in cosmetic satisfaction between PARS and open repair groups (88.4 vs. 76.0; p = 0.244).

CONCLUSION

Patients who underwent minimally invasive repair of acute Achilles tendon ruptures demonstrate no significant differences with respect to cosmesis, operative time, patient-reported outcomes and the rate and level of return to activities when compared to an open approach.

LEVEL OF EVIDENCE

III.

Biomechanical comparison of different suture materials with different techniques in tendon repair: An ex-vivo study

OBJECTIVES

Sheep Achilles tendons are used as an effective preclinical model of flexor tendon repair in plastic surgery, due to their biomechanical properties, which are similar to humans. The aim of this study was to examine the efficacy and biomechanical outcomes of suture materials and tendon repair techniques in flexor tendon repair.

MATERIAL AND METHODS

72 sheep tendons were obtained for a total of 12 different scenarios. Tendons were repaired using 4 different suture types and 3 different suture techniques. After repair, the tendons were fixed at both ends and subjected to biomechanical tests. Ultimate Failure Load (UFL) and 2-mm Gap Load (GL) per scenario were compared statistically within and between groups.

RESULTS

UFL and GL of all sutures were significantly different between the modified Kessler, Bunnell and Krackow techniques (P < 0.05), and between Monosorb, Ti-Cron and V-loc sutures (P < 0.05). UFL and GL according to repair technique were not significantly different for the Propilen suture (P > 0.05).

CONCLUSION

When UFL and GL were considered together, our findings indicate that optimal strength scenarios were for the modified Kessler technique using Monosorb or V-loc sutures.

Outcomes and Complications of Open Versus Minimally Invasive Repair of Acute Achilles Tendon Ruptures: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND

An acute Achilles tendon rupture is one of the most common sports injuries, affecting 18 per 100,000 persons, and its operative repair has been evolving and increasing in frequency since the mid-1900s. Traditionally, open surgical repair has provided improved functional outcomes, reduced rerupture rates, and a quicker recovery and return to activities at the expense of increased wound complications such as infections and skin necrosis compared with nonoperative management. In 1977, Ma and Griffith introduced the percutaneous approach, and over the following decades, multiple improved techniques, and modifications thereof, have been described with comparable outcomes with open repair.

PURPOSE

The current study aimed to provide updated level 1 evidence comparing open repair with minimally invasive surgery (MIS) through a comprehensive search of the literature published in English, Arabic, Spanish, Portuguese, and German while avoiding limitations of previous studies such as heterogeneous study designs and a small number of included trials.

STUDY DESIGN

Meta-analysis; Level of evidence, 1.

METHODS

Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, 2 independent team members searched several databases to identify randomized controlled trials (RCTs) comparing open repair and MIS of Achilles tendon ruptures. The primary outcomes were (1) functional outcomes, (2) reruptures, (3) sural nerve injuries, and (4) infections (deep/superficial), whereas the secondary outcomes were (1) skin complications, (2) adhesions, (3) other complications, (4) ankle range of motion, and (5) surgical time.

RESULTS

There were 10 RCTs that qualified for the meta-analysis with a total of 522 patients. Overall, 260 (49.8%) patients underwent open repair, while 262 (50.2%) underwent MIS. The mean postoperative AOFAS score was 94.8 and 95.7 for open repair and MIS, respectively, with a nonsignificant difference (mean difference [MD], -0.73 [95% CI, -1.70 to 0.25]; P = .14; I² = 0%). The pooled mean total complication rate was 15.5% (0%-36.4%) for open repair and 10.4% (0%-45.5%) for MIS, with a nonsignificant statistical difference (odds ratio [OR], 1.50 [95% CI, 0.87-2.57]; P = .14; I² = 40%). The mean rerupture rate was 2.5% (0%-6.8%) for open repair versus 1.5% (0%-4.6%) for MIS, with a nonsignificant statistical difference (OR, 1.56 [95% CI, 0.42-5.70]; P = .50; I² = 0%). No cases of sural nerve injuries were reported in the open repair group. The mean sural nerve injury rate was 3.4% (0%-7.3%) in the MIS group, which was statistically significant (OR, 0.16 [95% CI, 0.03-0.46]; P = .02; I² = 0%). The mean overall superficial infection rate was 6.0% (0%-18.2%) and 0.4% (0%-4.5%) for open repair and MIS, respectively, with a statistically significant difference (OR, 5.70 [95% CI, 1.80-18.02]; P < .001; I² = 0%). The mean overall deep infection rate reported in the open repair group was 1.4% (0%-5.0%), while no deep infection was reported in the MIS group, with no statistically significant difference (OR, 3.14 [95% CI, 0.48-20.54]; P = .23; I² = 0%). There were no significant differences between the open repair and MIS groups in the skin necrosis and dehiscence rate, adhesion rate, or keloid scar rate. The mean surgical time was 51.0 and 29.7 minutes for open repair and MIS, respectively, with a statistically significant difference (MD, 21.13 [95% CI, 15.50-26.75]; P < .001; I² = 15%).

CONCLUSION

Open Achilles tendon repair was associated with a longer surgical time, higher risk of superficial infections, and higher risk of ankle stiffness, while MIS was associated with a greater risk of temporary sural nerve palsy. The rerupture rate and functional outcomes were mostly equivalent. We found MIS to be a safe and reliable technique. However, high-quality standardized RCTs are still needed before recommending MIS as the gold standard for managing Achilles tendon ruptures.

Review of Achilles Tendon Reattachment Using Double-Row Knotted and Knotless Techniques in the Management of Insertional Achilles Tendinopathy

Insertional Achilles tendinopathy represents a chronic degenerative condition affecting the insertion of the Achilles. Surgery is indicated in recalcitrant cases and often involves extensive debridement followed by subsequent repair of the insertion. In the present study, we evaluate the results of knotted and knotless double-row suture systems for Achilles reattachment. Despite the popularity of double-row repairs, there is a relative paucity of clinic data regarding efficacy of the available implants. In a retrospective cohort study, 38 patients (40 Achilles tendons) who received double-row repairs between November 2012 and December 2016 were evaluated. In addition to demographic information, preoperative pain scores and symptom duration were recorded. Perioperative and postoperative records were reviewed, and telephone interviews were conducted to assess patient satisfaction, functional status, postoperative pain, and information regarding surgical complications. At a mean follow-up of 32.5 months, 35 (92.1%) patients reported satisfaction with the outcome. Decreased pain levels were reported in 38 (95%) ankles, with 21 (52.5%) ankles being rated pain-free postoperatively. Of the patients working prior to surgery, 20 (95.2%) were able to return to normal work duties, and all 11 (100%) patients who engaged in sports preoperatively were able to return to the same level of activity. Two patients developed postoperative infections, one of which required operative debridement. No Achilles avulsions were encountered. No significant differences were noted between the 2 operative techniques. Considering the available biomechanical data, along with high patient satisfaction rates and low rate of complications, double-row repair offers a viable option for recalcitrant insertional Achilles tendinopathy.

A Critical Biomechanical Evaluation of Foot and Ankle Soft Tissue Repair

The objective of this article is to review the biomechanical stresses that occur during normal physiologic function of lower extremity soft tissue anatomic structures and to use this as a baseline for a critical analysis of the medical literature because it relates to surgical reconstruction following injury. The Achilles tendon, anterior talofibular ligament, plantar plate, and spring ligament are specifically evaluated.

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

BACKGROUND

The 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.

METHODS

A 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.

RESULTS

12 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).

CONCLUSION

Nonabsorbable braided sutures is associated with the highest risk of postoperative wound complications following Achilles tendon rupture repair.

Endoscopic resection of enthesopathy via a direct midline transtendinous approach with associated reattachment of the Achilles tendon (endo-REDMTART): a cadaveric feasibility study

PURPOSE

The aim of our study was to determine the feasibility of an all-posterior endoscopic resection of enthesopathy via direct midline transtendinous approach with detachment and reattachment of the Achilles tendon (endo-REDMTART).

MATERIALS & METHODS

Endo-REDMTART was performed in 10 ankles by two foot and ankle surgeons. Posterolateral and posteromedial portals were utilized. Three accessory, more distal portals were utilized (one posterolateral, one posteromedial, and one midline transtendinous). We measured the quality of the resection of the calcaneal spur and the length of tendon that was able to be reattached to the calcaneus.

RESULTS

The procedure was successful in all 10 cases. The mean minimum thickness of resected calcaneal spur was 7 mm (5-9 mm) thick, and the mean anteroposterior distance was 23 mm (20-25 mm). In all 10 cases, the maximum distance between the distal Achilles tendon and calcaneus was 1 mm (0-1 mm), with good tendon-bone contact.

CONCLUSIONS

The data here suggest that endo-REDMTART is feasible. This procedure provides all of the advantages of endoscopic technique without compromising the efficacy of Haglund deformity resection.

TRIAL REGISTRATION

No Clinical Trials Registration or IRB is required.

LEVEL OF EVIDENCE

Anatomy study; cadaveric dissection.

Achilles Tendon Rip-Stop SpeedBridge Repair

Achilles tendon injuries have been on the rise secondary to our increased participation in sports, increase in societal obesity rates, and the growing elderly population. There has been disagreement in recent years about whether to treat injuries such as Achilles tendon ruptures operatively or nonoperatively with aggressive functional rehabilitation. For those opting to surgically manage Achilles tendon ruptures, insertional Achilles tendonitis, or augment the described SpeedBridge Achilles tendon repair, we propose a modified rip-stop technique. The goal of this technique is to provide a biomechanical advantage to our current operative interventions for these injuries, a greater load-to-failure and a speedier, more reliable return to sport in our athletic populations.

Modified triple Kessler with least risk of elongation among Achilles tendon repair techniques: a systematic review and network meta-analysis of human cadaveric studies

PURPOSE

Current treatment recommendations emphasize early loading, with preservation of tendon length and physiologic tension. The objective of this systematic review and network meta-analysis was to compare failure load and elongation after cyclic loading of Achilles tendon repair techniques at time-zero.

METHODS

The databases PubMed, CENTRAL and Web of Science were searched for all published in-vitro studies comparing Achilles tendon repair techniques, or augmentation with autografts/biomaterials, and reports of failure load or elongation after cyclic loading. Only studies using human cadaveric Achilles tendons and matched pairs, or randomized specimen allocation, were selected for quantitative synthesis. A network meta-analysis per primary outcome was performed. Results were summarized as P score rankings and their validity was assessed using statistical methods.

RESULTS

Sixteen studies, comprising 367 tendon repairs, were included. The following repair techniques were used (n = number of studies): Krackow (n = 8), Achillon (n = 4), double Krackow (n = 3), Bunnell (n = 3), Percutaneous Achilles Repair System (n = 3), Percutaneous Achilles Repair System Midsubstance (n = 2), Kessler (n = 3), double Kessler (n = 1), modified triple Kessler (n = 1), triple bundle (n = 1), a multifilament stainless steel cable-crimp technique (n = 1) and a double loop knot stitch (n = 1). Five studies assessed augmentation with autografts/biomaterials. Regarding the failure load, biomaterial augmented Krackow repairs occupied the first four positions in the ranking, followed by the multifilament stainless steel cable-crimp and Percutaneous Achilles Repair System Midsubstance techniques. Concerning elongation after cyclic loading, the triple Kessler was ranked first, followed by the Achillon and Percutaneous Achilles Repair System Midsubstance techniques. A negligible correlation between ranks was found (r_s = 0.11; p = 0.75n.s.), meaning that a higher repair tensile strength is not necessarily related to improved performance in regard to avoidance of elongation.

CONCLUSION

In the failure load network meta-analysis, biomaterial augmented Krackow repairs ranked highest, but noticeable statistical heterogeneity was found. Regarding elongation with cyclic loading, the modified triple Kessler stitch showed the highest probability of ranking first.

LEVEL OF EVIDENCE

Level IV.

Open versus minimally-invasive surgery for Achilles tendon rupture: a meta-analysis study

INTRODUCTION

Despite the presence of various different surgical procedures, the preferable technique for repair of acute Achilles tendon ruptures is unknown and, therefore, object of discussions. The purpose of this meta-analysis was to compare clinical outcomes and complication-rates between the minimally invasive and the standard open repair of acute Achilles tendon ruptures.

MATERIALS AND METHODS

This meta-analysis was performed according to the PRISMA guidelines. In September 2019 the main databases were accessed. All clinical trials of evidence level I to III comparing minimally invasive vs. open surgery of Achilles tendon rupture were included in the present study. Only articles reporting quantitative data under the outcomes of interest were included. Missing data under the outcomes of interest warranted the exclusion from the present work. For the statistical analysis we referred to the Review Manager Software Version 5.3. (The Nordic Cochrane Centre, Copenhagen). Continuous data were analysed through the inverse variance method. For the effect estimate the mean difference was used. Dichotomous data were analysed through the Mante-Haenszel method via odd ratio effect measure. The confidence interval was set at 95% in all the comparisons. Values of P < 0.05 were considered statistically significant.

RESULTS

A total of 25 articles were included for meta-analysis. The funnel plot revealed poor data dispersion, attesting to this study a low risk of publication bias. The quality of the methodological assessment was moderate. Data from 2223 (1055 open, 1168 minimally invasive) surgical procedures were extracted. The mean follow-up was of 24.29 ± 22.4 months. The open group reported a lower value of post-operative palpable knot at last follow-up and a lower rate of sural nerve palsy. In the minimally-invasive group a shorter surgery duration and a lower rate of post-operative wound necrosis and reduced risk of wound scarring and adhesions has been evidenced. The minimally-invasive cohort detected the lowest values of superficial and deep infections. In both groups no significant difference was shown in re-rupture rate.

CONCLUSIONS

Compared to the minimally-invasive Achilles tendon reconstruction, the open procedure evidenced a lower rate of sural nerve palsy and postoperative palpable knot, whereas in the minimally-invasive reconstruction group quicker surgery duration, a lower rate of post-operative wound necrosis, superficial and deep infections and less scar tissue adhesions could be observed. No relevant discrepancies were detected among the two techniques in terms of post-operative re-rupture.

Biomechanical Comparison of All-Soft Suture Anchor Single-Row vs Double-Row Bridging Construct for Insertional Achilles Tendinopathy

BACKGROUND

Two common operative fixation techniques for insertional Achilles tendinopathy are the use of all-soft suture anchors vs synthetic anchors with a suture bridge. Despite increasing emphasis on early postoperative mobilization, the biomechanical profile of these repairs is not currently known. We hypothesized that the biomechanical profiles of single-row all-soft suture anchor repairs would differ when compared to double-row suture bridge repairs.

METHODS

Achilles tendons were detached from their calcaneal insertions on 6 matched-pair, fresh-frozen cadaver through-knee amputation specimens. Group 1 underwent a single-row repair with all-soft suture anchors. Group 2 was repaired with a double-row bridging suture bridge construct. Achilles-calcaneal displacement was tracked while specimens were cyclically loaded from 10 to 100 N for 2000 cycles and then loaded to failure. Linear mixed models were used to analyze the independent effects of age, body mass index, tendon morphology, repair construct, and footprint size on clinical and ultimate failure loads, Achilles-calcaneal displacement, and mode of failure.

RESULTS

The suture bridge group was independently associated with an approximately 50-N increase in the load to clinical failure (defined as more than 5 mm tendon displacement). There was no difference in ultimate load to failure or tendon/anchor displacement between the 2 groups.

CONCLUSION

This cadaveric study found that a double-row synthetic bridge construct had less displacement during cyclic loading but was not able to carry more load before clinical failure when compared to a single-row suture anchor construct for the operative repair of insertional Achilles tendinopathy.

CLINICAL RELEVANCE

Our data suggest that double-row suture bridge constructs increase the load to clinical failure for operative repairs of insertional Achilles tendinopathy. It must be noted that these loads are well below what occurs during gait and the repair must be protected postoperatively without early mobilization. This study also identified several clinical factors that may help predict repair strength and inform further research.

No difference in strength and clinical outcome between early and late repair after Achilles tendon rupture

PURPOSE

This retrospective study aimed to determine the patient-reported and functional outcome of patients with delayed presentation, who had received no treatment until 14 days following injury of Achilles tendon rupture repaired with minimally invasive surgery and were compared with a group of sex- and age-matched patients presenting acutely. Based on the outcomes following delayed presentation reported in the literature, it was hypothesized that outcomes would be inferior for self-reported outcome, tendon elongation, heel-rise performance, ability to return to play, and complication rates than for acutely managed patients.

METHODS

Repair was performed through an incision large enough to permit mobilisation of the tendon ends, core suture repair consisting of a modified Bunnell suture proximally and a Kessler suture distally and circumferential running suture augmentation.

RESULTS

Nine patients presented 21.8 (14.9) days (range 14-42 days) after rupture. The rate of delayed presentation was estimated to be 1 in 10. At 12 months following repair, patients with delayed treatment had median (range) ATRS score of 90 (69-99) compared with 94 (75-100) in patients treated acutely presenting 0.66 (1.7) (0-5) days. There were no significant differences between groups: ATRA [mean (SD) delayed: - 6.9° (5.5), acute: - 6° (4.7)], heel-rise height index [delayed: 79% (20), acute: 74% (14)], or heel-rise repetition index [delayed: 77% (20), acute: 71% (20)]. In the delayed presentation group, two patients had wound infection and one iatrogenic sural nerve injury.

CONCLUSIONS

Patients presenting more than 2 weeks after Achilles tendon rupture may be successfully treated with minimally invasive repair.

LEVEL OF EVIDENCE

III.

Biomechanical comparison of Bunnell, modified Kessler, and Tsuge tendon repair techniques using two suture types

OBJECTIVE

The aim of this study was to compare the biomechanical properties of modified Kessler, Bunnell and Tsuge techniques in sheep Achilles tendon tear repaired using polyester and polydioxanone sutures which are also compared.

METHODS

Sixty sheep Achilles tendons were cut transversely as a substitute for rupture and repaired using modified Kessler, Bunnell and Tsuge techniques with No. 2 braided polyester and monofilament polydioxanone sutures. Specimens were loaded to failure. Four biomechanical parameters - ultimate strength (US), strength to 2 mm gap (S2G), strength to 5 mm gap (S5G) and Young's modulus (YM) - were recorded for statistical analysis.

RESULTS

The Tsuge-Polyester group demonstrated the highest results regarding S2G (21.24±4.75 N) (p=.002) and S5G (38.91±7.45 N) (p=.002). According to YM, the Bunnell-Polyester group was the most superior (1929.9±512.28 kilopascal) (p=.009). In the repairs with the polydioxanone suture, Bunnell technique achieved the best purchase with regard to S2G (18.14±6.86 N) (p=.006) and S5G (35.69±13.49 N) (p=.015). The difference between the three repair techniques with the polydioxanone suture was statistically insignificant regarding US (p=.252) and YM (p=.338). Concerning the repairs with the polyester suture, the repair techniques demonstrated no statistically significant difference in terms of US (p=.195), S2G (p=.667), S5G (p=.689) and YM (p=.195). Regarding the mean S2G and S5G values, the polyester suture was significantly superior to the polydioxanone suture in modified Kessler repairs (S2G: p<.001, S5G: p=.001) and Tsuge repairs (S2G: p<.001, S5G: p=.009). The polyester suture was also significantly superior to the polydioxanone suture in the modified Kessler repairs with respect to YM (p=.003).

CONCLUSION

This study supports the opinion that Tsuge technique is a promising procedure in Achilles tendon repair (ATR). For Tsuge and modified Kessler repairs, braided polyester suture use appears more advantageous compared to monofilament polydioxanone suture use in biomechanical terms.

The elastic capacity of a tendon-repair construct influences the force necessary to induce gapping

PURPOSE

Most biomechanical investigations of tendon repairs were based on output measures from hydraulic loading machines, therefore, accounting for construct failure rather than true gapping within the rupture zone. It was hypothesized that the elastic capacity of a tendon-repair construct influences the force necessary to induce gapping.

METHODS

A tendon-repair model was created in 48 porcine lower hind limbs, which were allocated to three fixation techniques: (1) Krackow, (2) transosseous and (3) anchor fixation. Loading was performed based on a standardized phased load-to-failure protocol using a servohydraulic mechanical testing system MTS (Zwick Roell, Ulm, Germany). Rupture-zone dehiscence was measured with an external motion capture device. Factors influencing dehiscence formation was determined using a linear regression model and adjustment performed as necessary. A 3-mm gap was considered clinically relevant. Analysis of variance (ANOVA) was used for comparison between groups.

RESULTS

The elastic capacity of a tendon-repair construct influences the force necessary to induce gapping of 3 mm (F_3mm) [β = 0.6, confidence interval (CI) 0.4-1.0, p < 0.001]. Furthermore, the three methods of fixation did not differ significantly in terms of maximum force to failure (n.s) or F_3mm (n.s).

CONCLUSION

The main finding of this study demonstrated that the higher the elastic capacity of a tendon-repair construct, the higher the force necessary to induce clinically relevant gapping.

LEVEL OF EVIDENCE

Controlled biomechanical study.

Does elasticity of Achilles tendon change after suture applications? Evaluation of repair area by acoustic radiation force impulse elastography

Background

Achilles tendon injuries are one of the most common tendon injuries. Surgical treatment is preferred in young and active patients. Although there are studies which evaluate the repair area with magnetic resonance imaging and ultrasonography after surgical treatment, there are very few studies which analyzes the elasticity of the tendon by quantitative methods. ARFI (acoustic radiation force impulse) elastography is a simple and non-invasive method that can quantitatively measure the elasticity of the soft tissues. Our study aims to evaluate the elasticity in the repair area of the surgically treated Achilles tendons, compare them to the non-injured side, and evaluate the effect of the suture method to the elasticity of the repaired tendons by using ARFI elastography.

Methods

In our retrospectively designed study, 19 patients who underwent surgical treatment with Krackow and modified Kessler suture methods after the Achilles tendon rupture between 2006 and 2014 were included. Shear wave velocity (SWV) of the repaired and non-injured Achilles tendons were measured by ARFI elastography in four different positions of the ankle.

Results

It was determined that SWV in the surgically repaired tendons were significantly higher in each four different position of the ankle, compared to the non-injured side (p < 0.01), indicating less elasticity in the repaired tendons. There was no statistically significant difference between the SWV of Krackow and modified Kessler suture method groups at four different positions of the ankle (p > 0.05). AOFAS Ankle-Hindfoot, VISA-A, VAS, and FAOS scores were not also statistically different between these two suture methods (p > 0.05).

Conclusions

In the repaired Achilles tendon, there is a decrease in the elasticity compared to the non-injured side. The functional and elastographic results of Krackow and modified Kessler suture methods are similar in long-term follow-ups of the patients.