Repair Of Achilles Tendon Rupture Research Articles

Limited open repair for achilles tendon rupture in the setting of co-morbidities: A case series and technique review

An acute Achilles tendon rupture poses a difficult treatment strategy in both young and old patients. Commonly considered an injury of the middle aged “weekend warrior,” an Achilles tendon tear in a sedentary patient is quite debilitating. An open surgical repair has many advantages including direct tendon visualization as well as the ability to interlock the suturing technique. Unfortunately, the extensive incision needed for proper tendon exposure creates a tenuous scenario primed for an increased risk of complications. The classic surgical incision disrupts the paratenon, the main blood supply to the watershed area of the tendon at the rupture site which is the weakest point of the repair. The minimal subcutaneous layer between the distal skin incision and the tendon has notoriously been a site of dehiscence. An infection in this area spreads quickly along the tendon planes with devasting consequences. These grave complications have led to a paradigm shift in repair techniques. Minimally invasive procedures utilize a percutaneous jig suturing system placed through a small incision at the site of rupture. Unfortunately, a distinct set of complications are associated with blind placement of fiber wire including sural nerve entrapment and incomplete tendon capture in the repair technique. A new technique merges the advantages of a small incision with the ability to directly visualize the tendon repair. The paratenon is maintained at the rupture site while being able to utilize an asymmetric offset classic suturing technique to add strength to the repair.

Traditional Open Repair and Reconstruction of Achilles Tendon Rupture

Despite the development of minimally invasive techniques and more effective nonoperative functional rehabilitation protocols, traditional open approaches remain viable options for both acute and chronic Achilles tendon rupture repair and reconstruction. Here, techniques for open Achilles tendon repair and reconstruction are discussed, along with outcomes, possible complications, and brief comparisons to other management options.Level of Evidence:Level V.

Quantitative Assessment of Calf Muscle Volume, Strength, and Quality After Achilles Tendon Rupture Repair: A 1-Year Prospective Follow-up Study

Background: A number of studies have reported that calf muscle atrophy is a common long-term problem after Achilles tendon repair; however, there is still a lack of data concerning early postoperative morphological changes in the calf muscle after surgery. Purpose: To investigate changes over time in calf muscle volume and fatty degeneration during 1 year after Achilles tendon repair. Study Design: Cohort study; Level of evidence, 2. Methods: A prospective 1-year serial magnetic resonance imaging study was carried out with 20 patients who underwent tendon repair for unilateral acute Achilles tendon rupture. The magnetic resonance imaging assessment in addition to clinical and functional evaluations was performed at 1, 3, 6, and 12 months after surgery. The muscle volume of the medial and lateral gastrocnemius, soleus, and flexor hallucis longus (FHL) and fatty degeneration of the medial and lateral gastrocnemius and soleus were measured for the calf muscles, and the relative volume and fatty degeneration changes in the affected leg compared with the healthy contralateral leg were calculated as a percentage ([injured/healthy control] × 100) to assess structural changes over time. Results: Muscle volumes of the medial gastrocnemius, lateral gastrocnemius, soleus, and FHL were 92.3%, 92.8%, 84.6%, and 95.9% at 12 months after surgery, respectively. Medial and lateral gastrocnemius and FHL muscle volumes improved over time and recovered to almost equal to that of the healthy side at 12 months after surgery. The soleus muscle volume did not recover significantly over time and was statistically significantly smaller than that of the healthy side at 12 months (P = .029). Fatty degeneration rates of the medial gastrocnemius, lateral gastrocnemius, and soleus were 118.2%, 113.9% and 121.1% at 12 months after surgery, respectively. Fatty degeneration of the medial and lateral gastrocnemius did not change significantly, but there was a statistically significant increase in fatty degeneration of the soleus over time (P < .001). Conclusion: Within the triceps surae muscle, the soleus was the most negatively affected by injury and repair for both muscle volume and fatty degeneration. Postoperative management to recover the soleus muscle function before a return to sporting activities should be considered in the future.

Early Tendon Morphology as a Biomarker of Long-term Patient Outcomes After Surgical Repair of Achilles Tendon Rupture: A Prospective Cohort Study

Background: Patient outcome after acute Achilles tendon rupture (ATR) varies and is difficult to predict. Whether early variations in healing, visualized with ultrasonography, can predict long-term patient outcome is unclear. Purpose: To (1) examine the associations of Achilles tendon cross-sectional area (CSA) and elongation (TE) during healing of ATR repair with patient outcomes at 12 months postoperatively and (2) investigate the predictive or diagnostic capacity of the morphological biomarkers. Study Design: Cohort study; Level of evidence, 2. Methods: This study was based on previously collected data from 86 patients who underwent acute standardized ATR repair between 2013 and 2018 and who were included in a prior randomized trial investigating early functional mobilization (EFM). In the EFM group, loading was allowed immediately after surgery, while in the comparison group, loading was allowed first at 2 weeks postoperatively. Achilles tendon CSA and length were measured with ultrasound at 6 weeks, 6 months, and 12 months postoperatively. CSA ratio and absolute difference in the length of the healthy and injured tendons were calculated. Patient-reported outcome was registered with the validated Achilles tendon Total Rupture Score and functional outcome with the heel-rise endurance test at 12 months postoperatively. The limb symmetry index (LSI) was calculated for maximum heel-rise height (HRHmax) and total concentric work. Multiple linear regression adjusted for age was used, and the area under the receiver operating characteristic curve (AUC) was calculated to evaluate predictive capacity. Results: A larger CSA ratio at 6 weeks was associated with higher LSI HRHmax at 12 months ( R2, 0.35; P &lt; .001) and exhibited good predictive capacity (AUC, 0.82). More TE at 12 months was associated with lower LSI total concentric work at 12 months ( R2, 0.21; P = .001) and exhibited acceptable predictive capacity (AUC, 0.71). Conclusion: Greater Achilles tendon CSA seen on ultrasound 6 weeks after surgical repair had good clinical prediction for long-term functional outcome. TE at 12 months was predictive of inferior functional outcome. Registration: NCT02318472 (ClinicalTrials.gov identifier).

Achilles tendon thickening does not affect elasticity and functional outcome after surgical repair of Achilles rupture: A retrospective study

PurposePrevious studies have confirmed that Achilles tendon occurs Achilles thickening after repair surgery of the rupture. Although this mechanism has been elucidated in the laboratory, there are few reports on its impact on clinical function. We designed a retrospective study to investigate the Achilles thickening after Achilles tendon rupture repair and its correlation between the elasticity and postoperative function. MethodsIn this retrospective analysis, patients who underwent surgical treatment for acute Achilles tendon rupture from April 2016 to April 2020 were included. All the patients were regularly followed up at 3 months, 1 year, and 2 years after surgery. American Orthopaedic Foot Ankle Surgeon (AOFAS) scale and Leppilahti score were used to evaluate functional outcomes. Achilles elasticity was measured by ultrasound shear wave of elasticity. Achilles thickening was calculated as maximal transverse and longitudinal diameter in cross-sectional plane of magnetic resonance scan. Sample t-tests was used for different follow-up periods. Correlation between Achilles thickening and other factors were analyzed using Pearson's method. p < 0.05 indicates a statistically significant difference. ResultsAOFAS scale and Leppilahti score at 1 year were significantly higher than at 3 months postoperatively (both p < 0.001). These functional scales were also improved at 2-year follow-up significantly (both p < 0.001). The dorsiflexion difference showed gradually recovery in each follow-up period (t = −17.907, p < 0.001). The elasticity of the Achilles appeared to continuously decreases during the postoperative follow-up period in all position sets (p < 0.001). In thickening evaluation, the cross-sectional area of the thickest plane of Achilles was significantly higher at 1 year postoperatively (310.5 ± 25.2) mm2 than that at 3 months postoperatively ((278.0 ± 26.2) mm2, t = −8.219, p < 0.001) and became thinner in 2-year magnetic resonance scan ((256.1 ± 15.1) mm2, t = 16.769, p < 0.001). The correlations between Achilles thickening, elasticity, and functional outcome did not show statistical significance (p > 0.05) in every follow-up period. ConclusionAchilles tendon thickens after surgery in the 1st year, but begins to gradually return to thinning about 2 years after surgery. There was no significant correlation between the increase and decrease of thickening and the patients' clinical function scores, Achilles elasticity, and bilateral ankle dorsiflexion difference.

The Association Between Distressed Community Index and Clinical Outcomes Following Surgical Repair of Acute Achilles Tendon Rupture

Category: Ankle; Other Introduction/Purpose: Operative management of acute Achilles tendon ruptures can be associated with a myriad of complications1,2. Demographics and comorbidities have been previously explored in relation to outcomes after operative management of Achilles tendon ruptures3,4. However, the relationship between socioeconomic factors and postoperative outcomes in these patients has not been explored. Distressed community index (DCI) is a score that represents a community’s level of well-being across the United States, with higher scores representing greater distress experienced in the community. Independent socioeconomic deprivation factors have been shown to be associated with suboptimal postoperative outcomes for patients undergoing certain orthopedic surgeries6–9. The purpose of this study is to determine if there is any association between DCI scores and short-term complication rates and functional outcomes following ruptured Achilles tendon repair. Methods: Patients who underwent surgical repair of ruptured Achilles tendon between 2015 and 2019 were identified. Patients’ residence zip codes were obtained and matched to corresponding DCI scores (0-100) based on data provided by the Economic Innovation Group for the same time period (2015-2019). Scores were divided into quintiles. Patient age, race, ethnicity, alcohol and smoking history, need for assistance with activities of daily living, ambulation status unrelated to injury, and access to transportation were also noted. Complications such as re-rupture, superficial or deep infection, wound complications, and deep vein thrombosis within 1-year since date of surgery were noted. Preoperative Foot and Ankle Ability Measure and Visual Analogy Pain scales were compared to postoperative scores at 6 months, 1 year, and 2 years. Analysis of variance (ANOVA) was used to determine the statistical significance of differences in the rate of complications and FAAM-VAS scores between quintiles. Results: Patients in the 2nd DCI quintile experienced the highest rate (9.25%) of total complications while patients in the 5th quintile experienced the lowest rate (3.33%). Difference in complication rates across DCI quintiles was not statistically significant (p=0.925). Out of the 17 patients who experienced complications, 12 (70.6%) patients belonged to the 1st and 2nd quintile while 2 patients (11.7%) belonged to the 4th and 5th quintiles. The differences in FAAM and VAS pain scores were not significantly different at preoperative and at 1-year and 2-year postoperative time points across quintiles. However, patients in the 5th and 4th quintiles experienced the greatest improvement in FAAM Overall scores at 1-year and 2-year postoperative time points, respectively. Conclusion: Patients living in more distressed communities did not experience greater postoperative complication rates or report lower patient-reported outcomes up to 2 years following operative repair of Achilles tendon rupture.

Postoperative Rehabilitation Protocols May Affect Rates of Achilles Tendon Re-Rupture after Acute Surgical Repair: A Systematic Review

Category: Ankle; Hindfoot Introduction/Purpose: Acute achilles tendon ruptures (AATR) are the most common tendon rupture in the lower limb with an incidence of up to 37 patients per 100,000 patient population annually. Several different guidelines exist on time to full weight bearing after AATR repair. Advantages of surgical management of AATR repairs are to maximize function of the tendon and reduce post-operative complications such as re-ruptures. A systematic review of the literature was performed which evaluated post-operative rehabilitation protocols, their complications and if an optimal post-operative treatment algorithm can be determined. Methods: In October 2022, MEDLINE, EMBASE and Cochrane Library databases were systematically reviewed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The level of evidence (LOE) and quality of evidence (QOE) were evaluated, and statistics on clinical outcomes, post-operative management and complications were calculated. Results: Eleven studies with 437 patients were included. Two studies were LOE I, three were LOE II, three were LOE III and three studies were LOE IV. Mean post-operative follow-up was 33.4 ± 31.2 months. Weighted mean post-operative return to full-weight bearing (FWB) was 4.8 ± 6.4 weeks. Post-operative return to neutral ankle position was achieved at an average of 4.6 ± 3.9 weeks. The overall complication rate was 3.0% (16 of 420 patients) with surgical wound infection (1.9%) and re-rupture (1.2%) the most common. Seven studies described an early rehabilitation protocol that commenced within 4 weeks from surgery. Subgroup analysis showed that early full weight-bearing (≤4 weeks) was associated with a higher re-rupture rate: 1.5% versus 0.7%. Conclusion: This systematic review demonstrated marked heterogenicity in reported rehabilitation protocols after AATR repair. While the risk of re-ruptures after surgical repair are low, we found that rehabilitation protocols that incorporate early weight- bearing within 4 weeks have a markedly increased risk of re-rupture. While there is increasing use of early rehabilitation after surgical repair of achilles tendon ruptures, further study is required to determine the optimal protocol to optimise outcome while decreasing the risk of failure.

Biomechanical Comparison of Open vs Percutaneous Techniques for Primary Mid-Substance Achilles Tendon Repair: A Systematic Review and Meta-Analysis

Category: Hindfoot; Basic Sciences/Biologics Introduction/Purpose: Primary repair of mid-substance Achilles tendon rupture may be performed using an open or a percutaneous technique. Previous meta-analyses of clinical data comparing the two techniques have demonstrated mostly equivalent functional outcomes and re-rupture rates. Individual cadaveric studies have also compared the biomechanical properties of the two approaches. However, the results of these studies have been heterogeneous, and there is currently no consensus as to whether one technique may be biomechanically superior. The purpose of this meta-analysis was to evaluate the biomechanical properties of open versus percutaneous Achilles tendon repair. Methods: A systematic review of original research articles was performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. To qualify for study inclusion, articles were required to be published in English, utilized a cadaveric laboratory design, and had to directly compare the biomechanical properties of open Achilles repair using a Krackow or Kessler technique versus percutaneous repair using either the PARS (Arthrex) or Achillon (Integra) tendon repair systems. Evaluated outcomes included displacement (mm), load to failure (N), and stiffness (N/m). Results: Nine studies met inclusion criteria, including 190 cadaveric specimens (open: 83, PARS: 56; Achillon: 51) that underwent primary mid-substance Achilles tendon repair. Pooled analysis demonstrated no statistically significant difference in displacement (p = 0.418; Figure 1), load to failure (p = 0.923; Figure 2), or stiffness (p = 0.195; Figure 3) between the open and percutaneous techniques. Among the percutaneous approaches, there was no difference in displacement (p = 0.109; Figure 4) between the PARS and Achillon tendon repair systems. Conclusion: The results of this study suggest that both open and percutaneous techniques are biomechanically viable approaches for primary mid-substance Achilles tendon repair. These biomechanical findings must be interpreted in the context of clinical outcomes data as well as the differing complication profiles of the two techniques to best inform the surgical decision-making process for primary mid-substance Achilles tendon repair.

Absorbable vs Nonabsorbable Sutures for Achilles Tendon Repair: A Systematic Review and Meta-analysis.

Nonabsorbable sutures are still the main choice for acute Achilles tendon rupture (AATR) repair due to strength provided. However, the rerupture rates, infection risks, foreign body reaction, and postsurgical recovery differences between absorbable and nonabsorbable suture materials in AATR repair have not been carefully reviewed. A systematic review was done on PubMed, EBSCO, Cochrane Central Register of Controlled Trials, and Embase to find research studies in relation to complications associated with AATR repair using the PRISMA guidelines. The risk of bias from each study included will be assessed using the Cochrane Risk of Bias Tool for randomized study (RoB 2) and Risk of Bias in Non-Randomized Studies of Interventions (ROBINS-I) for nonrandomized study. Five studies with a total of 255 patients, 105 in the absorbable suture group and 150 in the nonabsorbable suture group, were included for analysis. Risk of rerupture, infection, and foreign body reaction shown no significant difference between groups, and the mean difference of recovery scores were similar. Existing literature shows that absorbable sutures appear to be associated with similar outcomes to nonabsorbable sutures regarding rates of rerupture, infection, foreign body reaction, and outcomes grading following surgical repair of acute Achilles tendon repair.

The Influence of Patient Characteristics and Social Determinants of Health on Post-Operative Complications Following Achilles Tendon Ruptures

Category: Sports; Hindfoot Introduction/Purpose: While patient comorbidities are known to affect surgical complication rates after Achilles tendon rupture (ATR) repair, the correlation between social determinants of health (SDH) and postoperative complication rates is poorly understood. Two validated indices representative of SDH include the Area Deprivation Index (ADI), which ranks neighborhoods by social disadvantage, and the Social Vulnerability Index (SVI), which uses 16 US census variables to identify communities at risk before or after natural disasters. In this study, we aim to determine whether there is any correlation between patient demographics, SDH, and postoperative complication rates following surgical treatment of ATR. Methods: A retrospective chart review identified 521 patients who underwent surgical repair of an acute ATR between 2015 and 2021. Inclusion criteria included age ≥ 18 years, a minimum 30 day follow up, and patients who underwent acute repair within 28 days of ATR. Collected variables included patient demographics, time to surgery (TTS), injury characteristics, and postoperative complications sub-categorized into venous thromboembolism (VTE), re-rupture, surgical site infection (SSI), wound dehiscence, and sural nerve injury. SDH variables included age, race, smoking status, insurance status, level of education, and employment status. The ADI and SVI measurements of patient deprivation or vulnerability were also extracted from the data. A univariate regression test was performed to determine the correlation between each complication and each SDH indicator. Variables that showed significance (p &lt; 0.05) were then included in a multivariate regression to determine the correlation coefficients and significance. Results: Sixty-eight complications occurred in 59 patients (11.3%). Multivariate regression showed higher ADI was associated with VTE occurrence (OR = 0.39, 95% CI: 0.16 –0.91, p = 0.03). Female patients and open surgical approach correlated with decreased VTE occurrence (OR = 0.24, 95% CI: 0.09 – 0.66, p&lt; 0.01), (OR = 0.15, 95% CI: 0.04 – 0.55, p&lt; 0.01), respectively. Higher BMI was associated with VTE (OR = 1.62, 95% CI: 1.05 – 2.51, p=0.03) and re-rupture (OR = 3.86, 95% CI: 1.51 – 9.08, p&lt; 0.01). Women experienced decreased wound dehiscence rates (OR = 0.25, 95% CI: 0.09 – 0.69, p&lt; 0.01) and SSI (OR = 0.31, 95% CI: 0.11 – 0.93, p=0.04) compared to men. TTS correlated with sural nerve injuries (OR=2.09, 95% CI: 1.32 – 3.31, p&lt; 0.01). Conclusion: This study found that SDH, such as ADI, impacts complication rates after ATR repair, though the nature of this relationship remains unclear. Patient demographic and anthropometric factors such as gender and BMI also have an impact. Future studies should include a larger, more diverse sample population to better understand the impact of these factors on surgical outcomes.

Post-Operative Complications after Acute Achilles Tendon Rupture Repair: A Survival Analysis of Minimally Invasive vs Open Techniques

Category: Sports; Ankle Introduction/Purpose: Acute Achilles tendon ruptures (ATRs) can be treated surgically through either open repair or minimally invasive surgical techniques (MIS). While the relative complication rates between these techniques, including wound dehiscence, re-rupture, and sural nerve injury, have been debated, many studies demonstrate no significant difference between these two approaches. In this study, we conducted a Kaplan-Meier survival analysis to compare the incidence and timing of complications between open and MIS repair of acute ATRs and examine factors that may influence these rates. Methods: A retrospective study was conducted to evaluate the outcomes of patients (≥18 years) who underwent surgical intervention for acute ATR within a four-week period following injury, with a minimum follow-up of three months. Data on demographic variables, type of surgical procedure (MIS or open approach), and the occurrence and timing of postoperative complications were collected. Postoperative complications were classified as venous thromboembolism (VTE), re-rupture, surgical site infecti+D2on (SSI), wound dehiscence, and sural nerve injury.The Kaplan-Meier method was employed to compare the complication rates between the MIS and open repair groups. The log-rank test was used to test the equality of survivor functions. The Cox proportional hazards model was employed to determine predictors of complications. Results: In total, 417 patients were included in the final analysis. The MIS group had a higher proportion of patients with tobacco use. Fifty-two complications in 50 patients were recorded (Table 1). We found no significant difference in the complication rates between the MIS and open repair groups. However, Cox proportional hazards modeling revealed that body mass index (BMI) was a significant predictor of re-ruptures (HR 1.2, 95% CI = 1.05–1.4) and that surgical delay was found to be a significant predictor of wound dehiscence (HR 1.2, 95% CI =1.01–1.3) and sural nerve injury (HR 1.2, 95% CI =1.1–1.3). A surgical delay of more than 2 weeks was noted to have a positive likelihood ratio of 2.3 for wound dehiscence and 3.1 for sural nerve injury. Conclusion: The results of this study indicate that MIS and open repair techniques for acute ATRs demonstrate comparable complication rates. However, patients with elevated BMI exhibit an increased risk of re-rupture. Those with surgical delay beyond two weeks have an elevated likelihood of wound dehiscence and sural nerve injury, presumptively due to associated scaring and the requisite tissue manipulation. Surgeons and patients may consider these variables when formulating a surgical treatment plan.

The effect of smoking on 30-day complications following primary repair of Achilles tendon ruptures.

There exists a gap in the knowledge of the impact of smoking on Achilles tendon rupture repair. This study evaluates perioperative and postoperative complications associated with smoking to allow for a more informed evaluation and discussion with the patients when considering the surgical management of Achilles tendon repair in this patient population. The National Surgical Quality Improvement Program database was queried for patients undergoing Achilles tendon rupture repair from 2006 to 2019. Two patient cohorts were defined in this retrospective study: smokers and patients who did not smoke. The various patient demographics, medical comorbidities, and postoperative outcomes were compared using bivariate and multivariate analyses between the smoking and non-smoking groups. Of 4209 patients who underwent Achilles tendon repair, 3662 patients (87%) did not smoke, whereas 547 patients (13%) were smokers. Patients who were smokers were more likely to be younger and have a higher body mass index. Following multivariate analyses, those who smoked had an increased risk of experiencing wound dehiscence (OR 3.57; p = 0.013) and urinary tract infections (OR 1.21; p = 0.033) compared to non-smoking patients. Despite the rate of complications being relatively low in the short-term perioperative period, individuals who smoke should be counseled on the surgical risks they may experience following Achilles tendon repair, including wound dehiscence and urinary tract infections. Discussion preoperatively between the physician and patient who smoke can include ways in which postoperative care will be done to minimize the risk of adverse events, ultimately reducing costs for both the patient and the hospital.

Methods of Immobilization after Achilles Tendon Rupture Repair: A Comparative Study in Rat Model.

The Achilles tendon (AT) is the most frequently ruptured in the human body. Literature describing different immobilization methods' impact on tendon healing after AT repair is lacking. We compare plaster cast, splint, and K-wire to determine which is the most stable and has the fewest complications. Sixty rats aged 5-6 months were selected to establish Achilles tendon injury in two hind legs model. After suturing the ends of the AT together with a modified "Kessler" method (Prolene 5-0). The skin incision was interrupted and sutured with 1-0 thread. Rats were divided into three immobilization methods (plaster cast group, splint group, and K-wire group). In plaster cast group, the hind leg was cast with plaster in the extended position of the hip and knee joints, and the ankle joint was at 150°. Splint and K-wire group used splints and 0.8-mm K-wires, separately. The fixed period was 4 weeks. The incidence of stability and complications (death, necrosis of the legs, necrosis of the skin, and incisional infection) were recorded. Differences were detected using the chi-square test. Within 4 weeks observation, K-wires showed better stability (90%) compared with the other two ways (40% in plaster cast group, 65% in splint group; p < 0.05). Rats immobilized with K-wires (10%) suffered significantly lower complications compared with plaster cast and splint group (15%; p < 0.05). K-wire has better stability, lower complication rate than other methods. Immobilization with K-wire may be a promising tool in future clinical Achilles tendon rupture applications.

Correlation between the Coaptation and Regeneration of Tendon Stumps in Endoscopic Assisted Achilles Tendon Rupture Repair.

When the endoscopic Achilles tendon repair technique is utilized, direct stitching of the ruptured site is challenging due to the frayed tendon stumps. To explore whether undesirable coaptation of the tendon stumps influences the generation of the tendons. This study is a retrospective analysis of 46 patients who underwent a modified endoscopic Achilles tendon rupture repair from October 2018 to June 2020. Patients were divided into two groups according to the coaptation of tendon stumps on postoperative ultrasonography. Group 1 included 17 cases with undesirable coaptation (<50%), and Group 2 included 29 cases with appropriate coaptation (≥50%). Magnetic resonance imaging (MRI) was obtained postoperatively at 3, 6, and 12 months to evaluate the tendon morphological construction. Clinical evaluations were performed using the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hind foot score, the Achilles Tendon Total Rupture Score (ATRS), muscle power, and the Achilles tendon resting angle at the final follow-up. Complications were also encountered. The Student's t-test and the Mann-Whitney U-test were used to assess differences among both groups. The mean follow-up time was 37.5 ± 10.6 months in Group 1 and 39.0 ± 11.6 months in Group 2, respectively. The average age in Group 1 is slightly older than in Group 2 (37.3 ± 6.1 vs. 32.7 ± 6.3, p = 0.021). The tendon cross-section areas and thickness increased initially and decreased later on postoperative MRI evaluation. It also showed a significantly higher signal/noise quotient (SNQ) in Group 1 at postoperative 3 months. At postoperative 6 and 12 months, the SNQ between both groups was similar. The AOFAS score (95.9 ± 5.1 vs. 96.2 ± 4.9, p = 0.832), ATRS score (97.0 ± 3.6 vs. 97.7 ± 3.3, p = 0.527), and muscle power (21.38 vs. 24.74, p = 0.287) were not significantly different between both groups. However, the resting angle of Group 1 was significantly larger than that of Group 2 (4.6 ± 2.4 vs. 2.4 ± 2.3, p = 0.004). There was no difference in the complications (p = 0.628). Although complete regeneration can be finally achieved, the early stage of tendon stump regeneration can be prolonged due to undesirable coaptation when endoscopic Achilles tendon repair technique is applied. The prolonged high signal duration on MRI indicates the less-than-ideal regeneration of the tendon, which might lead to elongation of the tendon.

Case study: The influence of Achilles tendon rupture on knee joint stress during counter-movement jump – Combining musculoskeletal modeling and finite element analysis

BackgroundPresently, the current research concerning Achilles tendon rupture repair (ATR) is predominantly centered on the ankle joint, with a paucity of evidence regarding its impact on the knee joint. ATR has the potential to significantly impede athletic performance and increase tibiofemoral contact forces in athletes. The purpose of this study was to prognosticate the distribution of stress within the knee joint during a countermovement jump through the use of a simulation method that amalgamated a musculoskeletal model of a patient who underwent Achilles tendon rupture repair with a finite element model of the knee joint. MethodsA male elite badminton player who had suffered an acute Achilles tendon rupture in his right leg one year prior was selected as our study subject. In order to analyze his biomechanical data, we employed both the OpenSim musculoskeletal model and finite element model to compute various parameters such as joint angles, joint moments, joint contact forces, and the distribution of knee joint stress. ResultsDuring the jumping phase, a significantly lower knee extension angle (p < 0.001), ankle dorsiflexion angle (p = 0.002), peak vertical ground reaction force (p < 0.001), and peak tibiofemoral contact force (p = 0.009) were observed on the injured side than on the uninjured side. During the landing phase, the ankle range of motion (ROM) was significantly lower on the injured side than on the uninjured side (p = 0.009), and higher peak vertical ground reaction forces were observed (p = 0.012). Additionally, it is logical that an injured person will put higher load on the uninjured limb, but the finite element analysis indicated that the stresses on the injured side of medial meniscus and medial cartilage were significantly greater than the uninjured side. ConclusionsAn Achilles tendon rupture can limit ankle range of motion and lead to greater joint stress on the affected area during countermovement jumps, especially during the landing phase. This increased joint stress may also transfer more stress to the soft tissues of the medial knee, thereby increasing the risk of knee injury. It is worth noting that this study only involves the average knee flexion angle and load after ATR in one athlete. Caution should be exercised when applying the conclusions, and in the future, more participants should be recruited to establish personalized knee finite element models to validate the results.

Republication of "A Biomechanical Comparison of Limited Open Versus Krackow Repair for Achilles Tendon Rupture".

Soft tissue complications after Achilles tendon repair has led to increased interest in less invasive techniques. Various limited open techniques have gained popularity as an alternative to open operative repair. The purpose of this study was to biomechanically compare an open Krackow and limited open repair for Achilles tendon rupture. We hypothesized that there would be no statistical difference in load to failure, work to failure, and initial linear stiffness. A simulated Achilles tendon rupture was created 4 cm proximal to its insertion in 18 fresh-frozen cadaveric below-knee lower limbs. Specimens were randomized to open or limited open PARS Achilles Jig System repair. Repairs were loaded to failure at a rate of 25.4 mm/s to reflect loading during normal ankle range of motion. Load to failure, work to failure, and initial linear stiffness were compared between the 2 repair types. The average load to failure (353.8 ± 88.8 N vs 313.3 ± 99.9 N; P = .38) and work to failure (6.4 ± 2.3 J vs 6.3 ± 3.5 J; P = .904) were not statistically different for Krackow and PARS repair, respectively. Mean initial linear stiffness of the Krackow repair (17.8 ± 5.4 N/mm) was significantly greater than PARS repair (11.8 ± 2.5 N/mm) (P = .011). No significant difference in repair strength was seen, but higher initial linear stiffness for Krackow repair suggests superior resistance to gap formation, which may occur during postoperative rehabilitation. With equal repair strength, but less soft tissue devitalization, the PARS may be a favorable option for patients with risk factors for soft tissue complications.

Republication of "Open Repair of Acute Achilles Tendon Ruptures: Is the Incidence of Clinically Significant Wound Complications Overestimated?"

Conflicting evidence exists regarding the optimal management of acute Achilles tendon ruptures. Operative repair is thought to afford patients a lower risk of rerupture, albeit at a higher overall risk of wound complications. A retrospective chart review of 369 consecutive patients undergoing open repair of acute Achilles tendon ruptures performed by a single foot and ankle fellowship-trained orthopedic surgeon was undertaken. Healing was classified as no complications, complications without prolonging treatment, complications requiring prolonged local treatment, and complications requiring operative intervention. A statistical analysis comparing the rates of complications in this cohort to that reported in the literature was conducted. There were a total of 33 (8.94%) wound complications. Compared to the rates reported in the literature, no significant difference was detected (P = .3943; CI 6.24-12.33). However, when the complications not requiring additional treatment or prolonged care were excluded, only 9 wound complications (2.44%) were identified-a significantly lower complication rate than that reported in the literature (P < .0001; CI 1.12-4.58). There were only 2 (0.54%) major complications requiring operative intervention, also a significantly lower rate than in the literature (P < .0001; CI 0.067-1.94). In the past, wound-healing complications have been cited as a concern when treating patients operatively. We found that when solely looking at healing complications prolonging the patients' overall recovery, a significantly lower rate of complications existed compared to that reported in the literature. Level IV.

Poster 354: Biomechanical Comparison of Open versus Percutaneous Techniques for Primary Mid- Substance Achilles Tendon Repair: A Systematic Review and Meta-Analysis

Objectives: Primary repair of mid-substance Achilles tendon rupture may be performed using an open or a percutaneous technique. Previous meta-analyses of clinical data comparing the two techniques have demonstrated mostly equivalent functional outcomes and re-rupture rates. Individual cadaveric studies have also compared the biomechanical properties of the two approaches. However, the results of these studies have been heterogeneous, and there is currently no consensus as to whether one technique may be biomechanically superior. The purpose of this meta-analysis was to evaluate the biomechanical properties of open versus percutaneous Achilles tendon repair. Methods: A systematic review of original research articles was performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. To qualify for study inclusion, articles were required to be published in English, utilized a cadaveric laboratory design, and had to directly compare the biomechanical properties of open Achilles repair using a Krackow or Kessler technique versus percutaneous repair using either the PARS (Arthrex) or Achillon (Integra) tendon repair systems. Evaluated outcomes included displacement (mm), load to failure (N), and stiffness (N/m). Results: Nine studies met inclusion criteria, including 190 cadaveric specimens (open: 83, PARS: 56; Achillon: 51) that underwent primary mid-substance Achilles tendon repair. Pooled analysis demonstrated no statistically significant difference in displacement (p = 0.418; Figure 1), load to failure (p = 0.923; Figure 2), or stiffness (p = 0.195; Figure 3) between the open and percutaneous techniques. Conclusions: The results of this study suggest that both open and percutaneous techniques are biomechanically viable approaches for primary mid-substance Achilles tendon repair. These biomechanical findings must be interpreted in the context of clinical outcomes data as well as the differing complication profiles of the two techniques to best inform the surgical decision-making process for primary mid-substance Achilles tendon repair.

Biomechanical Comparison of Nonlocked Minimally Invasive and Locked Open Achilles Tendon Simulated Rupture Repairs.

Open repair of Achilles tendon ruptures is associated with a risk of infection and other wound complications. Although percutaneous repairs reduce these complications, they may increase the risk of nerve injury. This study was designed to determine whether a percutaneous nonlocking repair can approach the gapping resistance offered by a standard open repair under conditions approximating typical postoperative physiotherapy. Ten pairs of cadavers Achilles tendons were transected in situ 5 cm above the insertion. One tendon from each pair was repaired using an open 4-strand Krackow locking loop, and the contralateral tendon was repaired with the Achillon system using the same suture material. Displacement transducers were attached to the medial, lateral, anterior, and posterior aspects of the tendon, spanning the repair. Each tendon underwent 1000 tensile loading cycles to 86.5 N, simulating passive ankle range-of-motion physiotherapy. Gapping was documented on the 1st, 50th, 100th, 500th, and 1000th cycles. The ultimate tensile strength of each repaired tendon was then measured by distracting until gross failure occurred. Gapping of the percutaneous repairs exceeded that of conventional open repairs on the first, 500th, and 1000th load cycles. All 10 conventionally repaired tendons withstood 1000 load cycles without gross failure, but 4 of 10 percutaneous minimally invasive repairs failed, one on the 9th load cycle and the others between the 100th and 500th cycles. On average, tendons repaired with the open technique withstood 66% greater tensile load in failure testing than those repaired with the percutaneous technique. Open Krackow Achilles tendon repairs may better withstand more aggressive postoperative physiotherapy than nonlocked percutaneous repairs. The study suggests that surgeons should consider locking suture approaches to avoid loss of repair integrity with early motion.

Reverse Fragility Index Comparing Rates of Rerupture After Open Achilles Tendon Repair Versus Early Functional Rehabilitation: A Systematic Review of Randomized Controlled Trials

Background: Despite similar published rates of rerupture among patients treated with early functional rehabilitation and open repair for acute Achilles tendon rupture, uncertainty still exists regarding the optimal treatment modality. The reverse fragility index (RFI) is a statistical tool that provides an objective measure of the study’s neutrality by determining the number of events that need to change for a nonsignificant result to be significant. Purpose: The purpose was to utilize the RFI to appraise the strength of neutrality of randomized controlled trials (RCTs) comparing the rerupture rates of acute Achilles tendon ruptures treated with open repair versus early functional rehabilitation. Study Design: Systematic review; Level of evidence, 1. Methods: A systematic review was performed including all RCTs comparing the rerupture rates after operative repair and early functional rehabilitation for acute Achilles tendon ruptures. Studies were included that explicitly used early functional rehabilitation, defined as weightbearing and exercise-based interventions initiated within 2 weeks, as compared with open repair and reported a nonsignificant difference in rerupture rates. The RFI, with rerupture as the primary outcome, was calculated for each study (significance threshold, P < .05). The RFI quantifies a study’s strength of neutrality and is defined as the minimum number of event reversals necessary to change a nonsignificant result to statistically significant. Results: Nine RCTs were included, with 713 patients and 46 reruptures. The median (interquartile range) rerupture rate was 7.69% (6.38%-9.64%) overall, 4.00% (2.33%-7.14%) in the operative group, and 10.00% (5.26%-12.20%) in the nonoperative group. The median RFI was 3, indicating that an outcome reversal of 3 patients was necessary to change the results from nonsignificant to statistically significant. The median number of patients lost to follow-up was 6 (3-7). Of 9 studies, 7 (77.8%) had a loss to follow-up greater than or equal to its RFI. Conclusion: The statistical nonsignificance of studies reporting equivalent rerupture rates in the management of acute Achilles tendon ruptures with open repair versus nonoperative management with early functional rehabilitation can be reversed by changing the outcome status of only a few patients.