Individuals Post Achilles Tendon Rupture Exhibit Asymmetrical Knee and Ankle Kinetics and Loading Rates During a Drop Countermovement Jump

Functional Performance and Tendon Morphology After Operative or Nonoperative Treatment of Achilles Tendon Ruptures

Background

While controversy remains as to the relative benefit of operative (OM) versus non-operative management (NOM) of Achilles tendon (AT) ruptures (ATR), few studies have examined the effect on high impact maneuvers such as jumping and hopping.

Hypothesis/Purpose

The purpose of this study was to determine if functional performance including strength, jumping, and hopping outcomes differed between OM and NOM of acute ATR. The secondary objective was to assess the degree of association between AT morphology and performance outcomes.

Study Design

Retrospective cohort with a single prospective evaluation.

Methods

All patients were treated at an institutional secondary care center. Eligible participants (n=12 OM; 12 NOM) who were treated with OM or NOM of ATR within three weeks of injury were evaluated a minimum 20 months following ATR. AT length, thickness and gastrocnemius muscle thickness were assessed with B-mode ultrasound. Isokinetic plantar flexor strength, hop tests and countermovement and drop jumps were completed. Two-way ANOVAS were completed on all tests with unilateral values, independent t-tests were used for bilateral outcomes, and linear regressions were completed to assess the relationship between normalized AT length and performance.

Results

Affected limb AT was elongated and thickened (p\<0.01), gastrocnemius was atrophied (p\< 0.01) and angle-specific plantar flexor torque was reduced at 120°/s when measured at 20° plantar flexion (p = 0.028). Single leg drop vertical jump was higher in OM (p = 0.015) with no difference for hop and jump tests. AT length was related to plantar flexor torque but had no relationship with hopping performance.

Conclusions

Hop test performance was maintained despite plantarflexion weakness, gastrocnemius atrophy, and AT elongation. This may be the result of compensatory movement patterns. AT length holds limited explanatory power in plantar flexor strength, although this relationship should be evaluated further.

Level of Evidence

Level III.

Return-to-performance in elite soccer players after Achilles tendon ruptures: a study using a weighted plus/minus metric and matched-control analysis

PURPOSE

Studies have shown decreased match participation and shortened careers in athletes suffering Achilles tendon ruptures (ATRs), but assessment using a true performance metric is lacking. Plus/minus (PM) metrics provide a practical and objective approach to player performance assessment and are commonly used in other sports. This study aimed to quantify and compare individual player performance variations in elite football league players who sustained ATRs and returned to play within 1 year compared to those without ATRs, using a PM metric.

METHODS

Player and team data were sourced from Transfermarkt.com. Male players sustaining ATRs between 2007 and 2018 were identified through injury reports. A control group (CTRL) was matched by position, age, height, and league, with a 6:1 ratio of controls to ATR subjects. The day of injury was considered "time zero". Year -1 corresponds to the 360 days preceding injury, and Year 1 to the interval between 360 and 720 days after. Performance in the player's main team was evaluated using a previously validated weighted PM metric. Only data from Year -1 and Year 1 were used for ATR versus CTRL group comparisons. Statistical significance was set at p < 0.05.

RESULTS

The ATR group included 125 athletes. Data from more than 76,000 matches were analyzed. No statistically significant differences in net weighted PM metric between Year -1 and Year 1 were found.

CONCLUSION

No differences were found between athletes suffering from ATRs and controls regarding the weighted PM metric.

LEVEL OF EVIDENCE

III.

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

BACKGROUND

Presently, 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.

METHODS

A 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.

RESULTS

During 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.

CONCLUSIONS

An 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.

What is the Incidence of Subsequent Adjacent Joint Injury After Patellofemoral Pain?

OBJECTIVE

To investigate the incidence of subsequent lumbar spine, hip, and ankle-foot injuries after a diagnosis of patellofemoral pain.

DESIGN

Retrospective cohort study.

SETTING

Military Health System.

PARTICIPANTS

Individuals (n = 92,319) ages 17-60 diagnosed with patellofemoral pain between 2010-2011.

INTERVENTIONS

Therapeutic exercise.

MAIN OUTCOME MEASURES

Frequency of adjacent joint injuries in the 2-year period after initial patellofemoral pain injury, and hazard ratios (HR) with 95% confidence interval (CI) and Kaplan-Meier survival curves for risk of adjacent joint injury based on receiving therapeutic exercise for the initial injury.

RESULTS

After initial patellofemoral pain diagnosis, 42,983 (46.6%) individuals sought care for an adjacent joint injury. Of these, 19,587 (21.2%) were subsequently diagnosed with a lumbar injury, 2837 (3.1%) a hip injury, and 10,166 (11.0%) an ankle-foot injury. One in five (19.5%; n = 17,966) received therapeutic exercise which reduced the risk of having a subsequent lumbar (HR = 0.78, 95% CI 0.76-0.81), hip (HR = 0.93, 95% CI 0.87-0.98) or ankle-foot (HR = 0.86, 95% CI 0.83-0.90) injury.

CONCLUSION

The results suggest that a high number of individuals with patellofemoral pain will sustain an adjacent joint injury within 2 years although causal relationships cannot be determined. Receiving therapeutic exercise for the initial knee injury reduced the risk of sustaining an adjacent joint injury. This study helps provide normative data for subsequent injury rates in this population and guide development of future studies designed to understand causal factors.

No effects of early functional mobilization on gait patterns after acute Achilles tendon rupture repair

This study aimed to compare recovery of gait patterns in patients treated with early functional mobilization (EFM) or standard treatment (ST) after Achilles tendon rupture repair. Second, this study aimed to explore associations between gait patterns and tendon elongation and calf muscle atrophy, respectively. Forty-seven patients (12 females), mean age 38.7 (7.3) years, were included. Patients were postoperatively randomized to EFM (n = 29), including immediate weightbearing and ankle motion for 6 weeks, or ST (n = 18), with 2 weeks of unloading in a plaster cast followed by 4 weeks of weightbearing in an orthosis. Three-dimensional gait analyses were performed at 8 weeks and 6 months postoperatively to evaluate ankle and knee kinematics and kinetics. Ultrasound imaging was performed to assess tendon length and calf muscle atrophy. At 8 weeks, there were no significant group differences in ankle and knee kinematics and kinetics, while side-to-side differences between injured and uninjured side were present within both groups. At 6 months, the ST group exhibited higher generating ankle power and greater peak moments in ankle and knee compared to the EFM group. In both groups, peak ankle dorsiflexion angle was greater on the injured side compared to the uninjured side. No correlations were found between ankle joint gait deviations and degree of tendon elongation or muscle atrophy. Clinical significance: The accelerated rehabilitation regimen with EFM did not result in a more symmetrical gait pattern. The gait pattern deviations in the ankle joint were not related to the degree of muscle atrophy or tendon elongation.

Ground Reaction Forces during Vertical Hops Are Correlated with the Number of Supervised Physiotherapy Visits after Achilles Tendon Surgery

The objective of this study was to assess the effectiveness of, and the correlation between, an average of 42 supervised physiotherapy (SVPh) visits for the vertical ground reaction forces component (vGRF) using ankle hops during two- and one-legged vertical hops (TLH and OLH, respectively), six months after the surgical suturing of the Achilles tendon using the open method (SSATOM) via Keesler’s technique. Hypothesis: Six months of supervised physiotherapy with a higher number of visits (SPHNVs) was positively correlated with higher vGRF values during TLH and OLH. Group I comprised male patients (n = 23) after SSATOM (SVPh x = 42 visits), and Group II comprised males (n = 23) without Achilles tendon injuries. In the study groups, vGRF was measured during TLH and OLH in the landing phase using two force plates. The vGRF was normalized to the body mass. The limb symmetry index (LSI) of vGRF values was calculated. The ranges of motion of the foot and circumferences of the ankle joint and shin were measured. Then, 10 m unassisted walking, the Thompson test, and pain were assessed. A parametric test for dependent and independent samples, ANOVA and Tukey’s test for between-group comparisons, and linear Pearson’s correlation coefficient calculations were performed. Group I revealed significantly lower vGRF values during TLH and OLH for the operated limb and LSI values compared with the right and left legs in Group II (p ≤ 0.001). A larger number of visits correlates with higher vGRF values for the operated limb during TLH (r = 0.503; p = 0.014) and OLH (r = 0.505; p = 0.014). An average of 42 SVPh visits in 6 months was insufficient to obtain similar values of relative vGRF and their LSI during TLH and OLH, but the hypothesis was confirmed that SPHNVs correlate with higher relative vGRF values during TLH and OLH in the landing phase.

Indirect Structural Muscle Injuries of Lower Limb: Rehabilitation and Therapeutic Exercise

Muscle injuries are the most common trauma in team and individual sports. The muscles most frequently affected are those of the lower limb, and in particular hamstrings, adductors, rectus femoris and calf muscles. Although several scientific studies have tried to propose different rehabilitation protocols, still too often the real rehabilitation process is not based on scientific knowledge, especially in non-elite athletes. Moreover, the growing use of physical and instrumental therapies has made it increasingly difficult to understand what can be truly effective. Therefore, the aim of the present paper is to review proposed therapeutic algorithms for muscle injuries, proposing a concise and practical summary. Following a three-phase rehabilitation protocol, this review aims to describe the conservative treatment of indirect structural muscle injuries, which are the more routinely found and more challenging type. For each phase, until return to training and return to sport are completed, the functional goal, the most appropriate practitioner, and the best possible treatment according to current evidence are expressed. Finally, the last section is focused on the specific exercise rehabilitation for the four main muscle groups with a structured explanatory timetable.

Functional Ankle Range of Motion but Not Peak Achilles Tendon Force Diminished With Heel-Rise and Jumping Tasks After Achilles Tendon Repair

BACKGROUND

Deficits in sporting performance after Achilles tendon repair may be due to changes in musculotendinous unit structure, including tendon elongation and muscle fascicle shortening.

PURPOSE/HYPOTHESIS

The purpose was to discern whether Achilles tendon rupture reduces triceps surae muscle force generation, alters functional ankle range of motion, or both during sports-related tasks. We hypothesized that individuals who have undergone Achilles tendon repair lack the functional ankle range of motion needed to complete sports-related tasks.

STUDY DESIGN

Descriptive laboratory study.

METHODS

The study included individuals 1 to 3 years after treatment of Achilles tendon rupture with open repair. Participants (n = 11) completed a heel-rise task and 3 jumping tasks. Lower extremity biomechanics were analyzed using motion capture. Between-limb differences were tested using paired t test.

RESULTS

Pelvic vertical displacement was reduced during the heel-rise (mean difference, -12.8%; P = .026) but not during the jumping task (P > .1). In the concentric phase of all tasks, peak ankle plantarflexion angle (range of mean difference, -19.2% to -48.8%; P < .05) and total plantar flexor work (defined as the area under the plantar flexor torque - ankle angle curve) (range of mean difference, -9.5% to -25.7%; P < .05) were lower on the repaired side relative to the uninjured side. No significant differences were seen in peak Achilles tendon load or impulse with any of the tasks. There were no differences in plantar flexor work or Achilles tendon load parameters during eccentric phases.

CONCLUSION

Impaired task performance or increased demands on proximal joints were observed on the repaired side in tasks isolating ankle function. Tasks that did not isolate ankle function appeared to be well recovered, although functional ankle range of motion was reduced with rupture. Reduced plantar flexor muscle-tendon unit work supports previous reports that an elongated tendon and shorter muscle fascicles caused by Achilles tendon rupture constrain functional capacity. Achilles tendon peak load and impulse were not decreased, suggesting that reduced and shifted functional ankle range of motion (favoring dorsiflexion) underlies performance deficits.

CLINICAL RELEVANCE

These findings point to the need to reduce tendon elongation and restore muscle length of the triceps surae after Achilles tendon rupture in order to address musculature that is short but not necessarily weak for improved performance with sports-related activities.

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.

Achilles tendon elongation after acute rupture: is it a problem? A systematic review

PURPOSE

Rupture of the Achilles tendon (AT) is a common injury. Strength deficits may persist over the long term, possibly owing to elongation of the tendon or inferior mechanical properties. This study aimed to provide a systematic review of the literature on the prevalence and consequences of tendon elongation in patients after acute AT rupture treatment. It was hypothesized that an elongated tendon would be associated with a worse clinical outcome.

METHODS

The databases for MEDLINE, CENTRAL and Web of Science were searched. Clinical studies related to AT rupture reporting tendon elongation and clinical or functional outcomes, with a minimum follow-up of 6 months, were eligible for inclusion. Only studies testing for statistical correlations (SCs) between AT elongation and other outcomes were eligible, with the exception of biomechanical studies in which statistically significant AT elongation was found to be a generalized finding in the study group. For these studies to be eligible, the study group had to be compared with a healthy control group, or the injured limb compared with the uninjured limb, regarding biomechanical parameters.

RESULTS

Twenty-eight papers were selected for inclusion. Mean AT elongation measured with imaging techniques ranged from 0.15 to 3.1 cm (n = 17). Ten studies investigated SCs with Patient Reported Outcome Measures (PROMs), in which two found SCs with tendon elongation. Five studies reported strength and power evaluations and their correlation with AT elongation, with two having found SCs between decreased strength and tendon elongation. In ten studies reporting data on biomechanical tests, nine found influence of tendon elongation. In this group, four out of five studies found SCs with biomechanical parameters.

CONCLUSION

Fair evidence of the influence of tendon elongation in biomechanical parameters was found. In a general population, evidence of a detrimental effect of tendon elongation on PROMs or functional strength at follow-up was not found in this review.

LEVEL OF EVIDENCE

Level IV.

A Pilot Study of Musculoskeletal Abnormalities in Patients in Recovery from a Unilateral Rupture-Repaired Achilles Tendon

The purpose of this study was to compare the inter-limb joint kinematics, joint moments, muscle forces, and joint reaction forces in patients after an Achilles tendon rupture (ATR) via subject-specific musculoskeletal modeling. Six patients recovering from a surgically repaired unilateral ATR were included in this study. The bilateral Achilles tendon (AT) lengths were evaluated using ultrasound imaging. The three-dimensional marker trajectories, ground reaction forces, and surface electromyography (sEMG) were collected on both sides during self-selected speed during walking, jogging and running. Subject-specific musculoskeletal models were developed to compute joint kinematics, joint moments, muscle forces and joint reaction forces. AT lengths were significantly longer in the involved side. The side-to-side triceps surae muscle strength deficits were combined with decreased plantarflexion angles and moments in the injured leg during walking, jogging and running. However, the increased knee extensor femur muscle forces were associated with greater knee extension degrees and moments in the involved limb during all tasks. Greater knee joint moments and joint reaction forces versus decreased ankle joint moments and joint reaction forces in the involved side indicate elevated knee joint loads compared with reduced ankle joint loads that are present during normal activities after an ATR. In the frontal plane, increased subtalar eversion angles and eversion moments in the involved side were demonstrated only during jogging and running, which were regarded as an indicator for greater medial knee joint loading. It seems after an ATR, the elongated AT accompanied by decreased plantarflexion degrees and calf muscle strength deficits indicates ankle joint function impairment in the injured leg. In addition, increased knee extensor muscle strength and knee joint loads may be a possible compensatory mechanism for decreased ankle function. These data suggest patients after an ATR may suffer from increased knee overuse injury risk.

Achilles tendon cross-sectional area at 12 weeks post-rupture relates to 1-year heel-rise height

PURPOSE

Achilles tendon rupture leads to long-term plantar flexor deficits, but some patients recover functional performance better than others. Early indicators of tendon healing could be helpful in establishing patient prognosis and making individualized decisions regarding rehabilitation progression. The purpose of this study was to investigate relationships between early tendon morphology and mechanical properties to long-term heel-rise and jumping function in individuals after Achilles tendon rupture.

METHODS

Individuals after Achilles tendon rupture were assessed at 4, 8, 12, 24, and 52 weeks post-injury. Tendon cross-sectional area, length, and mechanical properties were measured using ultrasound. Heel-rise and jump tests were performed at 24 and 52 weeks. Correlation and regression analysis were used to identify relationships between tendon structural variables in the first 12 weeks to functional outcomes at 52 weeks, and determine whether the addition of tendon structural characteristics at 24 weeks strengthened relationships between functional performance at 24 and 52 weeks. Functional outcomes of individuals with < 3 cm of elongation were compared to those with > 3 cm of elongation using a Mann-Whitney U test.

RESULTS

Twenty-two participants [mean (SD) age = 40 (11) years, 17 male] were included. Tendon cross-sectional area at 12 weeks was the strongest predictor of heel-rise height (R² = 0.280, p = 0.014) and work symmetry (R² = 0.316, p = 0.008) at 52 weeks. Jumping performance at 52 weeks was not significantly related to any of the tendon structural measures in the first 12 weeks. Performance of all functional tasks at 24 weeks was positively related to performance on the same task at 52 weeks (r = 0.456-0.708, p < 0.05). The addition of tendon cross-sectional area improved the model for height LSI (R² = 0.519, p = 0.001). Tendon elongation > 3 cm significantly reduced jumping symmetry (p < 0.05).

CONCLUSION

Tendon cross-sectional area and excessive elongation related to plantar flexor performance on functional testing after Achilles tendon rupture. Once an individual is able to perform function-based testing, tendon structural measures may inform long-term prognosis. Ultrasound-based measures of tendon structure early in recovery seem to relate to later performance on functional testing. Clinically, assessing tendon structure has the potential to be used as a biomarker of tendon healing early in recovery and better predict patients at risk of negative functional outcome.

LEVEL OF EVIDENCE

II.

Italian consensus statement (2020) on return to play after lower limb muscle injury in football (soccer)

Return to play (RTP) decisions in football are currently based on expert opinion. No consensus guideline has been published to demonstrate an evidence-based decision-making process in football (soccer). Our aim was to provide a framework for evidence-based decision-making in RTP following lower limb muscle injuries sustained in football. A 1-day consensus meeting was held in Milan, on 31 August 2018, involving 66 national and international experts from various academic backgrounds. A narrative review of the current evidence for RTP decision-making in football was provided to delegates. Assembled experts came to a consensus on the best practice for managing RTP following lower limb muscle injuries via the Delphi process. Consensus was reached on (1) the definitions of 'return to training' and 'return to play' in football. We agreed on 'return to training' and RTP in football, the appropriate use of clinical and imaging assessments, and laboratory and field tests for return to training following lower limb muscle injury, and identified objective criteria for RTP based on global positioning system technology. Level of evidence IV, grade of recommendation D.

Changes in gait mechanics and muscle activity with wedge height in an orthopaedic boot

BACKGROUND

Orthopaedic boots with wedging are commonly used in the treatment of individuals with Achilles tendon rupture to immobilize the foot in plantar flexion and approximate tendon ends.

RESEARCH QUESTION

To describe changes in muscle activity of the triceps surae and gait mechanics with the use of wedges in an orthopaedic boot immediately and after an accommodation period.

METHODS

Muscle activity of the triceps surae and gait parameters (vertical ground reaction force, knee extension power, gait speed) were collected using surface electromyography and motion capture in 12 healthy individuals. Participants walked in an instrumented orthopaedic boot with 0, 3, and 5 wedges tested in random order. Participants were provided a one hour accommodation period where time spent walking was collected. This was followed by a repeat assessment of triceps surae activity and gait.

RESULTS

Peak and integrated EMG in the medial gastrocnemius (p = 0.001, p < 0.001) and soleus (p = 0.010, p < 0.001) significantly decreased with increasing number of wedges. Peak and integrated EMG had a slight but non-significant decrease with increasing number of wedges in the lateral gastrocnemius (p = 0.151, p = 0.077). Vertical ground reaction force decreased (p = 0.019) and peak knee extension power increased (p = 0.003) with increasing number of wedges. There were no statistically significant differences in gait speed with wedges (p = 0.450). There were no significant changes in EMG or gait parameters from pre- to post-accommodation period.

SIGNIFICANCE

A combination of factors yield decreased triceps surae activity in individuals wearing an orthopaedic boot with wedges - decreasing loading on the immobilized limb and shifting power generation proximally.