Minimally Invasive Achilles Repair Techniques

The top 50 most cited articles on minimally invasive Achilles tendon repair: a bibliometric analysis

PURPOSE

Achilles tendon rupture is an increasingly common injury seen in athletic and active populations which can be corrected through strategic operative techniques. The purpose of this study is to identify and review the top 50 most cited articles discussing minimally invasive Achilles tendon repair with regards to the operative technique, outcomes, and complications.

METHODS

Scopus database was used to search for publications focusing on minimally invasive Achilles tendon repair. The top 50 most cited articles were screened for inclusion criteria and reviewed for year published, journal of publication, country of origin, study type, level of evidence, and citation density.

RESULTS

The total number of citations from the top 50 most cited articles was 1,415 with a range of five to 168 citations per article. The year of publication ranged from 2004 to 2020, with the majority (n = 33) being published from 2010 to 2020. The most common level of evidence rating was III (25 articles), most of which were cohort studies. The next most common level of evidence rating was IV (11 articles), which were mostly case series. The articles were written across 18 countries, most commonly the United Kingdom (18%), and were published in 28 journals with Foot and Ankle International being the most prolific journal (n = 8).

CONCLUSION

The results of this study highlighted the prevalence of cohort studies, case series, and technical notes for minimally invasive Achilles tendon repair research. This demonstrates the need for more research with higher level, controlled studies to examine minimally invasive Achilles tendon repair techniques, outcomes, and complications in the future.

Functional outcomes following minimally invasive Achilles rupture repair: a retrospective comparative study of PARS and midsubstance speedbridge techniques

BACKGROUND

Prior studies have compared patient-reported outcomes between open repair and one of either the two minimally invasive techniques for Achilles tendon rupture: Percutaneous Achilles Repair System (PARS) and Midsubstance Speedbridge Implant System (MSB). However, no study has compared patient-reported outcomes measured by Patient Reported Outcomes Measurement Information System (PROMIS) physical function (PF) and PROMIS pain interference (PI) and the Achilles Tendon Total Rupture Score (ATRS) between PARS and MSB. Our study compared patient-reported outcomes measured by PROMIS and ATRS scores between PARS and MSB. We hypothesized that patient-reported outcomes would be similar between groups.

METHODS

This was a retrospective review of 434 patients who underwent Achilles rupture repair from 2018 to 2023 at a single institution. Tendinopathies, open injuries, concomitant fractures, tendon transfers, gastrocnemius recessions, and open repairs were excluded. A total of 316 patients met inclusion criteria and were contacted to complete a postoperative questionnaire containing PROMIS and ATRS. 119 (78 PARS and 41 MSB) completed all surveys and were included for final analysis. Wilcoxon rank-sum and Kruskal-Wallis tests were used to assess differences in mean scores. Chi-squared and Fisher's exact tests were used to compare incidence of complications. All tests were conducted at a significance level of α = 0.05.

RESULTS

Average follow-up was 30 months at time of survey completion. There were no significant differences in PROMIS PF, PROMIS PI, and ATRS measures between groups (p > 0.05). Mean PARS PROMIS PF, PROMIS PI, and ATRS were 58.8, 44.2, and 86.0, respectively. Mean MSB PROMIS PF, PROMIS PI, and ATRS were 55.3, 44.0, and 82.5, respectively. No significant differences existed in incidence of each postoperative complication between groups (p > 0.05).

CONCLUSION

In the largest study to compare patient-reported outcomes between PARS and MSB, outcomes were similar between both groups. Both techniques resulted in PROMIS PF greater than the population mean and PROMIS PI lower than the population mean. Each had similar ATRS scores. Overall, both MSB and PARS were safe and effective strategies for surgically managing Achilles ruptures.

The Medial Mini-Open Supine Achilles Repair: Outcomes of a Medially Based Mini-Open Technique Compared With Prone Techniques

BACKGROUND

Achilles tendon rupture treatment has changed substantially in the past decade, with an evolution toward less-invasive techniques and more convenient patient positioning. This review aims to report on the 1-year clinical outcomes of a medially based, mini-open, supine, Achilles tendon repair technique.

METHODS

In this retrospective review, all patients who underwent surgical management of an Achilles tendon rupture were included and analyzed based on approach, including (1) standard open prone technique, (2) mini-open repair, prone, and (3) medial mini-open repair, supine. Primary outcomes were the Patient-Reported Outcome Measures Information Systems (PROMIS) Physical Function, PROMIS Pain Interference, and PROMIS Depression scores. Secondary outcomes of interest were surgical time and complications.

RESULTS

Seventy-eight patients were included in this study who underwent Achilles tendon repair and were seen in follow-up at least 1-year postoperatively. Demographics are displayed in Table 1. No statistical difference was observed regarding sex, laterality, age, and mechanism between those with 1-year follow-up data and those who were lost to follow-up before the 1-year mark. Primary outcomes were notable for statistically significant difference in the PROMIS Depression score between the mini-open repair, prone group, and the mini-open repair, supine group. The remainder of the primary outcomes of interest were not statistically significant. Secondary outcomes were notable for markedly shorter surgical time for the mini-open repair, supine group compared with both the standard open prone and mini-open repair, prone groups, with times being 89, 72, and 58 minutes, respectively. Surgical time was defined as starting from the time the patient was anesthetized in the room and included positioning and time up until extubation.

CONCLUSION

The medial mini-open repair, supine technique shows promise as a noninferior surgical option for acute Achilles tendon rupture repair with markedly decreased operating room time and 1-year outcomes with comparable results to both open and mini-open prone techniques.

Global burden of disease for musculoskeletal disorders in all age groups, from 2024 to 2050, and a bibliometric-based survey of the status of research in geriatrics, geriatric orthopedics, and geriatric orthopedic diseases

BACKGROUND

Orthopaedic diseases in the elderly pose a significant disease burden, and the number of research papers on the subject is increasing every year.

METHODS

The GBD database was used to analyze the global disease burden of musculoskeletal disorders in all age groups from 2024 to 2050. The source for bibliometrics was the WoSCC SCI-E database.

RESULTS

Global disability-adjusted life years (DALYs) for musculoskeletal disorders by age were dominated by those aged 70 years and older, but the rate of change in DALYs between 2024 and 2050 was approximately ± 1%. We performed a descriptive analysis of 164,521 geriatrics articles, and 7155 geriatric orthopedics and geriatric orthopedic articles, and performed clustering, co-citation, collaborative network, and burst citation analyses based on Citespace and VOSviewer. Seven clustering tags containing hot content and 26 burst citation keywords containing hot content were finally targeted.

CONCLUSION

DALY in older adults over 70 years of age accounts for a significant portion of the disease burden of musculoskeletal disorders. Possible future research hotspots in geriatric orthopedics and geriatric bone diseases include three directions: (1) novel clinical procedures and postoperative management (2) various comorbidities caused by SARS-CoV-2 infections and other pathogens; and (3) effectiveness of Stem Cell Therapy in Clinical Applications and Biological Mechanisms of Stem Cell Therapy.

Long-Term Outcomes Following Surgical Intervention for Achilles Tendon Rupture: A Systematic Review With a Minimum Five-Year Follow-Up

Achilles tendon (TA) rupture is a common injury. However, there is limited evidence on the long-term outcomes following surgical repair. This systematic review aims to evaluate the efficacy and complications associated with surgical management of TA rupture with a minimum five-year follow-up duration. A literature search of Medline OVID, EMBASE, and Cochrane databases was performed adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The outcomes measured focused on postoperative complications, rates of re-rupture, contralateral rupture, and revision surgery. Six studies including 806 patients were included. Surgical repair demonstrated low re-rupture rates (4.2%) and revision rates (3.7%) at five years follow-up. Contralateral ruptures were uncommon (N=5), and 30 patients required revision surgery. However, complications such as deep vein thrombosis (6.3%) and wound infections (3.6%) were observed. Surgical repair of TA rupture demonstrates excellent long-term outcomes, including low rates of re-rupture and revision over a minimum of five years. While complications such as deep vein thrombosis and wound infections are observed, this systematic review highlights the reliability, durability, and overall success of surgical intervention in effectively treating this condition.

Achilles Rupture Repair: Modified Gift-Box With a Proximal Myotendinous Backup Fixation Technique

Achilles tendon tears are not an uncommon injury, with a predominance in explosive athletes and weekend warriors in the third to fifth decade of life. Consideration of operative intervention is commonplace in young athletes, whereas less active and older individuals may opt for nonsurgical treatment. Surgical treatment is reported to improve functional outcomes in high-demand individuals and demonstrates increased plantarflexion power, better return to sports rates, and a reduced rerupture rate. Traditionally, a primary end-to-end repair of the Achilles tendon was the surgical treatment of choice. More recently, alternative advanced techniques and minimally invasive constructs have been proposed in an effort to improve repair construct while reducing soft tissue complications. This technical note describes a technique that combines a modified gift-box primary repair with backup fixation using calcaneal anchors. This technique is performed with a small, medially based incision that reduces wound and nerve complications, while promoting end-to-end tendon healing by reducing tension across the repair site through the calcaneal backup fixation.

Ultrasound-Guided Percutaneous Achilles Tendon Repair for Acute Achilles Tendon Rupture: Modified Percutaneous Achilles Repair System Procedure for Achilles Tendon Repair Without a Jig

Surgical methods for treating Achilles tendon ruptures include open and minimally invasive surgery (MIS). MIS offers notable advantages, including reduced rates of infection and wound necrosis; however, it also introduces the risk of sural nerve injury. Intraoperative ultrasonography can mitigate this risk by providing real-time visualization of the sural nerve and Achilles tendon, improving clinical outcomes. This article introduces a novel ultrasound-guided suturing technique for Achilles tendon repair using a percutaneous Achilles repair system (PARS). This technique does not require the use of a jig, which is conventionally used in the standard PARS procedure to ensure accurate and controlled percutaneous suture placement in the Achilles tendon, making it less invasive than conventional methods. Additionally, it allows for more precise intraoperative visualization of the sural nerve using ultrasonography, enabling safer Achilles tendon repair.

Mini-open versus percutaneous surgical repair for acute Achilles tendon rupture: a systematic review and meta-analysis

PURPOSE

To compare the clinical outcomes and complications of mini-open (MOT) and percutaneous techniques (PT) in the surgical repair of acute Achilles tendon rupture (AATR).

METHODS

We systematically searched PubMed, Scopus, Web of Science, Clinical Trials, and the Cochrane Library for studies comparing MOT with PT for AATR. We assessed functional outcomes, complication rates, and operation time. Statistical analyses were performed using RevMan Web. Odds ratios (ORs) and mean difference (MD) with 95% confidence intervals (CIs) were pooled with a fixed-effects model for dichotomous and continuous endpoints, respectively. Heterogeneity was evaluated with I2 statistics.

RESULTS

Eight studies, comprising 484 patients, were included, of whom 226 (46%) underwent MOT. MOT was associated with a significantly lower re-rupture rate (1.48% vs. 6.11%; OR 0.28; 95% CI 0.09-0.86; p = 0.03; I2 = 6%) and sural nerve injury rate (0.57% vs. 5.64%; OR 0.24; 95% CI 0.07-0.81; p = 0.02; I2 = 0%). No significant differences were observed in venous thrombosis (OR 0.81; 95% CI 0.17-3.94; p = 0.33; I2 = 0%), wound infection (OR 0.56; 95% CI 0.12-2.62; p = 0.46; I2 = 0%), or operation time (MD 1.83 min; 95% CI -1.13-4.79; p = 0.23; I2 = 88%). Functional outcomes showed higher American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot scores in the MOT group (MD 1.52 points; 95% CI 0.62-2.42; p = 0.001; I2 = 3%), while (Achilles Tendon Total Rupture Score) ATRS, time to return to activities, and ankle plantar and dorsiflexion were comparable.

CONCLUSIONS

MOT for AATR repair seems to reduce re-ruptures and sural nerve injuries while improving AOFAS scores, with no significant differences in other complications compared to PT. These findings suggest that the MOT may offer a safer and equally effective alternative to PT for AATR.

The option of transosseous distal suture placement during minimally invasive Achilles tendon repair for high-risk patients can improve outcomes, however does not prevent re-rupture

PURPOSE

Achilles tendon ruptures (ATRs) close to the insertion, in high-level athletes, and in patients at high risk of re-rupture, may be better suited to operative repair. Minimally Invasive Repair (MIR) of the Achilles tendon has excellent outcome and low complication rates. Traditionally MIR has showed lower repair strength, failing due to suture pull-out from the distal tendon stump. The aim of this study was to describe the outcome of ATR patients who received transosseous distal suture placement using a standard technique as a reference.

METHODS

Following ATR, patients were evaluated for pre-injury activity level, body weight, location of the tear and size of the distal Achilles tendon stump. Patients considered to be at high-risk of re-rupture: Tegner level ≥ 8, body weight ≥ 105Kg and distal ATR, received transosseous (TO) distal suture placement (n = 20) rather than the usual transtendinous (TT) technique (n = 55). Patient reported outcome measures and functional evaluation was performed at 12 months following repair.

RESULTS

At 12 months follow up both methods resulted in good median (IQR) Achilles tendon Total Rupture Score TO 83.8 (74-88.3) vs. TT 90 (79-94), low increased relative Achilles Tendon Resting Angle TO -3.5˚ (3.6) vs. TT -3.5˚ (3.3) and mean (SD) Single leg Heel-Rise Height Index TO 88.2% (9.9) vs. TT 85.6% (9.9) (n.s.). There were 4 re-ruptures in the high-risk group and 2 in the group receiving TT distal suture placement. All but one of these were traumatic in nature. The mode of failure following TO distal suture placement was proximal suture pull out.

CONCLUSIONS

To distal suture placement during minimally-invasive Achilles tendon repair for higher-risk patients can lead to results equivalent to those in lower-risk patients treated with a standard TT MIR technique, except for the re-rupture rate which remained higher. There may be factors that have greater influence on outcome other than suture placement following ATR.

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.

Percutaneous Achilles Tendon Repair Using Ultrasound Guidance: An Intraoperative Ultrasound Technique

Rupture of the Achilles tendon is a common injury seen in patients of varying ages and activity levels. There are many considerations for treatment of these injuries, with both operative and nonoperative management providing satisfactory outcomes in the literature. The decision to proceed with surgical intervention should be individualized for each patient, including the patient's age, future athletic goals, and comorbidities. Recently, a minimally invasive percutaneous approach to repair the Achilles tendon has been proposed as an equivalent alternative to the traditional open repair, while avoiding wound complications associated with larger incisions. However, many surgeons have been hesitant to adopt these approaches due to poor visualization, concern that suture capture in the tendon is not as robust, and the potential for iatrogenic sural nerve injury. The purpose of this Technical Note is to describe a technique using high-resolution ultrasound guidance intraoperatively during minimally invasive repair of the Achilles tendon. This technique minimizes the drawbacks of poor visualization associated with percutaneous repair, while providing the benefit of a minimally invasive approach.

Operative Versus Nonoperative Treatment of Acute Achilles Tendon Rupture: A Propensity Score-Matched Analysis of a Large National Dataset

Background

No consensus exists regarding the superiority of operative versus nonoperative management for Achilles tendon ruptures, as multiple randomized controlled trials conducted since the advent of early mobilization protocols have found outcomes for these 2 interventions to be more similar than were previously held.

Purpose

To use a large national database to (1) compare reoperation and complication rates between operative and nonoperative treatment of acute Achilles tendon ruptures and (2) evaluate trends in treatment and cost over time.

Study Design

Cohort study; Level of evidence, 3.

Methods

The MarketScan Commercial Claims and Encounters database was used to identify an unmatched cohort of 31,515 patients who sustained primary Achilles tendon ruptures between 2007 and 2015. Patients were stratified into operative and nonoperative treatment groups, and a propensity score-a matching algorithm-was used to establish a matched cohort of 17,996 patients (n = 8993 per treatment group). Reoperation rates, complications, and aggregate treatment costs were compared between groups with an alpha level of .05. A number needed to harm (NNH) was calculated from the absolute risk difference in complications between cohorts.

Results

The operative cohort experienced a significantly larger total number of complications within 30 days of injury (1026 vs 917; P = .0088). The absolute increase in cumulative risk was 1.2% with operative treatment, which resulted in an NNH of 83. Neither 1-year (1.1% [operative] vs 1.3% [nonoperative]; P = .1201) nor 2-year reoperation rates (1.9% [operative] vs 2% [nonoperative]; P = .2810) were significantly different. Operative care was more expensive than nonoperative care at 9 months and 2 years after injury; however, there was no difference in cost between treatments at 5 years. Before matching, the rate of surgical repair for Achilles tendon rupture remained stable, from 69.7% to 71.7% between 2007 and 2015, indicating little change in practice in the United States.

Conclusion

Results indicated no differences in reoperation rates between operative and nonoperative management of Achilles tendon ruptures. Operative management was associated with an increased risk of complications and higher initial costs, which dissipated over time. Between 2007 and 2015 the proportion of Achilles tendon ruptures managed operatively remained similar despite increasing evidence that nonoperative management of Achilles tendon rupture may provide equivalent outcomes.

Outcomes of Percutaneous Achilles Repair Compared With Endoscopic Flexor Hallucis Longus Tendon Transfer to Treat Achilles Tendon Ruptures

BACKGROUND

Both percutaneous and endoscopically assisted methods are reported to produce good results in the surgical management of acute Achilles tendon ruptures. The aim of this retrospective study was to compare between a percutaneous method and a recently described isolated endoscopically assisted flexor hallucis longus (FHL) transfer method as surgical means of management in patients with acute Achilles tendon ruptures.

METHODS

One hundred seventeen patients were included in the current study and divided into 2 groups: 59 patients who underwent percutaneous Achilles repair (PAR Group) and 58 patients who underwent isolated endoscopic FHL transfer (FHL Group) were compared. Patients were clinically evaluated using American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, Achilles tendon Total Rupture Score (ATRS), and Achilles tendon resting angle (ATRA) measures. In addition, ankle plantarflexion power, FHL dynamometry, Tegner activity levels, and return to previous levels of activity were also documented for all patients.

RESULTS

Nine months after surgery, patients in the FHL transfer group were more likely to be able to return to normal activities (91% vs 73%, P < .01). Thirty months after surgical treatment, we found no difference in ATRS, AOFAS, ATRA, ankle plantarflexion strength, or Tegner activity scores between study groups. Overall complications were reported in 6 patients in the FHL group (10.3%) and in 8 patients in the PAR group (13.6%). No major neurovascular or skin complications were encountered.

CONCLUSION

The current study demonstrated satisfactory and comparable results and complications when comparing isolated endoscopic FHL tendon transfer or percutaneous Achilles tendon repairs in the surgical management of acute Achilles tendon ruptures.

LEVEL OF EVIDENCE

Level III, retrospective controlled trial.

Slowed-Down Rehabilitation Following Percutaneous Repair of Achilles Tendon Rupture

BACKGROUND

Following percutaneous repair of acute Achilles tendon (AT) ruptures, early postoperative weightbearing is advocated; however, it is debatable how aggressive rehabilitation should be. We compared the clinical and functional outcomes in 2 groups of patients who followed either our "traditional" or a "slowed down" rehabilitation after percutaneous surgical repair.

METHODS

Sixty patients were prospectively recruited to a slowed down (29 patients) or a traditional (31 patients) rehabilitation program. Both groups were allowed immediate weightbearing postoperatively; a removable brace with 5 heel wedges was applied at 2 weeks. In the slowed-down group, 1 wedge was removed after 4 weeks. Gradual removal of the boot took place after 4 wedges were kept for 4 weeks. In the traditional group, 1 wedge was removed every 2 weeks, with removal of the boot after 2 wedges had been kept for 2 weeks. The AT Resting Angle (ATRA) evaluated tendon elongation. Patient reported functional outcomes were assessed using the AT Rupture Score (ATRS). Calf circumference difference and the isometric plantarflexion strength of the gastro-soleus complex were evaluated.

RESULTS

At the 12-month follow-up, both ATRA and ATRS were more favorable in the slowed-down group. The isometric strength and the calf circumference were more similar to the contralateral leg in the slowed-down group than in the traditional one.

CONCLUSION

Following percutaneous repair of acute Achilles tendon patients undergoing slowed down rehabilitation performed better than the traditional one. These conclusions must be considered within the limitations of the present study.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

Mechanical and Shape Memory Properties of Electrospun Polyurethane with Thiol-Ene Crosslinking

The ability to treat complex medical issues often requires dynamic and versatile materials. Electrospinning is a fabrication technique which produces nano-/microfibers that can mimic the extracellular matrix of many biological tissues while shape memory polymers allow for geometric changes in devices upon implantation. Here, we present the fabrication of electrospun polyurethane which exhibits the shape memory effect. To improve the mechanical and shape memory properties of this system, we incorporate vinyl side chains in the polymer backbone which enable crosslinking via thiol-ene click chemistry post fabrication. We also discuss a novel technique to improve photoinitiated crosslinking for electrospun materials. A material with these properties is potentially beneficial for various medical applications, such as vascular anastomosis, and the characterization of this material will be valuable in directing those applications.

Comparison of mini-open repair system and percutaneous repair for acute Achilles tendon rupture

Background

To reduce incision complications, minimally invasive operative approaches for treatment with acute Achilles tendon rupture have been developed, such as Mini-open repair and percutaneous repair. Which technique is the better surgical option? In the present study, we compared the two surgical procedures— modified Mini-open repair versus percutaneous repair—in the treatment of acute Achilles tendon rupture.

Methods

From January 2016 to November 2018, 68 matched patients with acute Achilles tendon rupture were divided into treatment group (Mini-open with modified Ma-Griffith technique) and control group (the Ma–Griffith technique). The patients were then treated with different surgical techniques and followed up for no less than 24 months, and the functional outcome scores and complications were retrospectively evaluated.

Results

The mean follow-up time in Mini-open repair group was 29.0±2.9 months, and that in control group was 27.9±2.9 months (P=0.147). The Mini-open repair group showed reliably higher American Orthopedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Score and Achilles tendon Total Rupture Score (ATRS) than the control group in functional assessment (95.0±3.8 vs. 92.3±5.3, P=0.000; 93.8±3.8 vs. 90.9±4.5,P=0.000). There was no cases of sural nerve injury in Mini-open repair group, whereas the percutaneous repair group had 5 cases of the same (P=0.027). No significant differences were found in the calf circumference (32.3±3.9 vs. 31.8±3.6) (P=0.564), range of motion of the ankle (51.3±4.8 vs. 50.5±4.2, P=0.362), or wound complications (34/0 vs. 34/0) (P=1.000) between the two groups at the end of the follow-up time. However, the percutaneous repair group had a shorter average operating time (23.1±5.2 min) than that of the Mini-open repair group (27.7±4.3 min) (P=0.000).

Conclusions

Acute Achilles tendon ruptures may be treated successfully with a new Mini-open repair system or percutaneous repair technique. However, the Mini-open repair system may represent a superior surgical option, since it offers advantages in terms of direct visual control of the repair, AOFAS Ankle-Hindfoot Score, Achilles tendon Total Rupture Score and risk of sural nerve palsy.

Study design

Case-control studies, Level of evidence, 3.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04802-8.

Jigless knotless internal brace versus other open Achilles tendon repairs using a progressive rehabilitation protocol: a biomechanical study

BACKGROUND

The jigless knotless internal brace surgery (JKIB), a modified minimal invasive surgery (MIS) for acute Achilles tendon injury, has advantages of preventing sural-nerve injury in MIS and superficial wound infection in open surgery, as demonstrated in previous clinical research. However, to date, biomechanical testing has not yet been validated.

MATERIALS AND METHODS

Sixty fresh porcine Achilles tendons were used to compare the JKIB with other open surgery techniques, the four-stranded Krackow suture (4sK) and the triple-bundle suture (TBS) in biomechanical testing with cyclic loading set at 1 Hz. This approach simulated a progressive rehabilitation protocol where 20-100 N was applied in the first 1000 cycles, followed by 20-190 N in the second 1000 cycles, and then 20-369 N in the third 1000 cycles. The cycles leading to repair gaps of 2 mm, 5 mm, and 10 mm were recorded. The survival cycles were defined as repair gap of 10 mm.

RESULTS

With respect to survival cycles, a significant difference was found among the three groups, in which the TBS was the most robust, followed by the JKIB and the 4sK, where the mean survived cycles were 2639.3 +/- 263.55, 2073.6 +/- 319.92, and 1425.25 +/- 268.96, respectively. Significant differences were verified via a post hoc analysis with the Mann-Whitney U test after the Bonferroni correction (p < 0.017).

CONCLUSIONS

The TBS was the strongest suture structure in acute Achilles tendon repair. However, the JKIB could be an option in acute Achilles tendon repair with the MIS technique due to it being more robust than the 4sK, which has been typically favored for use in open repair.

Modified mini-incision "internal splinting" versus percutaneous repair technique of acute Achilles tendon rupture: five year retrospective case-controlled study

PURPOSE

Several kinds of minimally invasive surgical techniques are applied to acute Achilles tendon rupture. The risks of sural never injury and re-ruptures are still major issues. The purpose of this study was to compare the middle-term results of two different minimally invasive repair techniques for acute Achille tendon rupture.

METHODS

Twenty-four cases underwent the modified mini-incision "internal splinting" repair technique in group A, and 29 cases underwent a percutaneous repair technique in group B and were evaluated. The intra-operative data, complications, the time of recovery, and the post-operative magnetic resonance imaging were analyzed. At the final follow-up, the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and Thermann score were evaluated.

RESULTS

The mean follow-up time was 59.96 ± 4.16 months (range 48-67). At the final follow-up, the AOFAS score and Thermann score in both groups had similar feedback. No nerve injury, infection, or re-rupture was encountered in group A, except two cases with anchor irritation. One case with sural nerve injury and one with a re-rupture were recorded in group B, respectively. The final MRI showed thicker regeneration of the tendon in both groups.

CONCLUSIONS

The middle-term results indicated the modified mini-incision "internal splinting" technique for acute Achilles tendon rupture is similar to the percutaneous repair technique. A lower risk of sural nerve injury and re-rupture may be advantages.

Histological evaluation of the effect of low-frequency electric stimulation on healing Achilles tendons in rats

PURPOSE

Histologically evaluate the effects of low frequency electrical stimulation in the treatment of Achilles tendon injuries in rats.

METHODS

Thirty-four rats underwent Achilles tendon tenotomy and tenorrhaphy. They were randomly allocated in two groups. Half of the sample constituted the experiment group, whose lesions were stimulated with 2 Hz, nonpolarized current and 1 mA, for 14 days. The other animals formed the control group. They were evaluated at 2, 4 and 6 weeks. The histological study was carried out, the collagen density and the wound maturity index were measured.

RESULTS

The healing score was higher in the group stimulated at the 6th week (p = 0.018). The density collagen 1 was higher in the group treated at the three times (p = 0.004) and that collagen 3 was higher in the group treated at 6 weeks (p = 0.004). Together, collagen 1 and 3 were higher in the group stimulated at 4 and 6 weeks (p = 0.009, p = 0.004). The maturity index was higher in this group at the three moments (p = 0.017 p = 0.004 and p = 0.009).

CONCLUSION

Low frequency electric stimulation improved healing and increased the quantity of collagen.

Tensiometric evaluation of the effect of lowfrequency electric stimulation on healing Achilles tendons in rats

PURPOSE

To evaluate the effects of low-frequency electric stimulation on biomechanics following surgical treatment of the Achilles tendon in rats.

METHODS

Forty-two rats were divided into two groups. One was given electric stimulation and the other was not. All were submitted to Achilles tenotomy and tenorrhaphy performed with a modified Kessler stitch. The experiment group underwent electric stimulation with 2 Hz, a nonpolarized current of 1 mA intensity for 14 days. The animals were euthanized at 2, 4 and 6 weeks for the biomechanical study.

RESULTS

The work performed, that is, the tendon's capacity to absorb energy until rupture, was greater in the electrically stimulated group in the 2nd (p = 0.032) and in the 6th week (p = 0.010). The maximum tension, which is the capacity to support a load, was higher in the treated group in the 2nd (p = 0.030) and the 6th week (p = 024). These results indicate greater resistance of the electrically stimulated tendons. An analysis of the elastic module showed no differences.

CONCLUSION

Low-frequency electric stimulation increased the resistance of the tendons at 2 and 6 weeks of evolution in rats.