No clinically relevant difference between operative and non-operative treatment in tendon elongation measured with the Achilles tendon resting angle (ATRA) 1 year after acute Achilles tendon rupture

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.

Current Concepts in Achilles Tendon Ruptures

The Achilles tendon has a high incidence of ruptures often occurring in weekend warriors and the aging population. Based on anatomic studies of the Achilles tendon, ruptures are commonly found in the watershed area proximal to the insertion site. Traditionally, treatment options included conservative therapy with immobilization and a prolonged non-weight-bearing phase versus surgical treatment. Surgical treatment can vary between open, minimally invasive, or percutaneous approaches. In more recent years, early functional rehabilitation with or without surgery has shown to have successful results.

1.7 cm elongated Achilles tendon did not alter walking gait kinematics 4.5 years after non-surgical treatment

PURPOSE

The aim of the present study was to evaluate Achilles tendon length after non-surgical treatment of acute Achilles tendon rupture (aATR), and to evaluate indirect effects of possible persistent elongation on kinematics.

METHODS

The study was performed as a cross-sectional study based on a population of patients from an RCT regarding non-operative treatment of aATR. Thirty-seven patients out of the 56 in the original RCT participated with at a follow up of 4-5 years after aATR. Primary outcome was Achilles tendon elongation. Additional outcomes were Achilles tendon resting angle (ATRA), calf circumference, passive ankle plantar and dorsiflexion and loading pattern. Foot pressure mapping was performed to measure plantar loading distribution pattern; medial and lateral forefoot peak pressure, heel peak pressure, medial versus lateral loading pattern and timing of heel lift during roll over process. The healthy leg was used as a control.

RESULTS

The injured Achilles tendon was significantly elongated by 1.7 (SD 1.6) cm compared to the non-injured leg. A slight delay of 2.6% (SD 6.0) was measured in heel lift in the injured side compared to the non-injured leg. We found no significant difference in forefoot peak pressure, medial and lateral peak pressure as well as heel peak pressure, and no correlation was found between Achilles tendon length and pressure measurements. Finally, dorsiflexion was 1.9°(SD1.28) larger, ATRA 8.1°(SD6.7) larger, and calf circumference 1.6 cm (SD1.1) lower on the injured leg.

CONCLUSION

The Achilles tendon was 1.7 cm elongated 4.5 years after the initial injury and significant changes in ATRA, calf circumference and passive dorsiflexion was present. Except for a slight delay in heel lift-off, kinematics during walking was symmetrical between injured and healthy leg, even with an elongated tendon on the injured leg. The clinical relevance of the Achilles tendon elongation is uncertain.

LEVEL OF EVIDENCE

II.

CLINICAL TRIALS IDENTIFIER

NCT02760784.

Early Tensile Loading in Nonsurgically Treated Achilles Tendon Ruptures Leads to a Larger Tendon Callus and a Lower Elastic Modulus: A Randomized Controlled Trial

BACKGROUND

Early tensile loading improves material properties of healing Achilles tendon ruptures in animal models and in surgically treated human ruptures. However, the effect of such rehabilitation in patients who are nonsurgically treated remains unknown.

HYPOTHESIS

In nonsurgically treated Achilles tendon ruptures, early tensile loading would lead to higher elastic modulus 19 weeks after the injury compared with controls.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 2.

METHODS

Between October 2015 and November 2018, a total of 40 nonsurgically treated patients with acute Achilles tendon rupture were randomized to an early tensile loading (loaded group) or control group. Tantalum bead markers were inserted percutaneously into the tendon stumps 2 weeks after the injury to allow high-precision measurements of callus deformation under mechanical testing. The loaded group used a training pedal twice daily to produce a gradual increase in tensile load during the following 5 weeks. Both groups were allowed full weightbearing in an ankle orthosis and unloaded range of motion exercises. Patients were followed clinically and via roentgen stereophotogrammetric analysis and computed tomography at 7, 19, and 52 weeks after the injury.

RESULTS

The mean ± standard deviation elastic modulus at 19 weeks was 95.6 ± 38.2 MPa in the loaded group and 108 ± 45.2 MPa in controls (P = .37). The elastic modulus increased in both groups, although it was lower in the loaded group at all time points. Tendon cross-sectional area increased from 7 weeks to 19 weeks, from 231 ± 99.5 to 388 ± 142 mm² in the loaded group and from 188 ± 65.4 to 335 ± 87.2 mm² in controls (P < .001 for the effect of time). Cross-sectional area for the loaded group versus controls at 52 weeks was 302 ± 62.4 mm² versus 252 ± 49.2 mm², respectively (P = .03). Gap elongation was 7.35 ± 13.9 mm in the loaded group versus 2.86 ± 5.52 mm in controls (P = .27).

CONCLUSION

Early tensile loading in nonsurgically treated Achilles tendon ruptures did not lead to higher elastic modulus in the healing tendon but altered the structural properties of the tendon via an increased tendon thickness.

REGISTRATION

NCT0280575 (ClinicalTrials.gov identifier).

The epidemiology of Achilles tendon re-rupture and associated risk factors: male gender, younger age and traditional immobilising rehabilitation are risk factors

PURPOSE

The aim of this study was to describe the epidemiology of Achilles tendon re-rupture. Secondary aims were to identify factors predisposing to increased Achilles tendon re-rupture risk, at the time of primary Achilles tendon rupture.

METHODS

A retrospective review of all patients with primary Achilles tendon rupture and Achilles tendon re-rupture was undertaken. Two separate databases were compiled: the first included all Achilles tendon re-ruptures presenting during the study period and described epidemiology, mechanisms and nature of the re-rupture; the second was a case-control study analysing differences between patients with primary Achilles tendon rupture during the study period, who did, or did not, go on to develop re-rupture, with minimum review period of 1.5 years.

RESULTS

Seven hundred and eighty-three patients (567 males, 216 females) attended with primary Achilles tendon rupture and 48 patients (41 males, 7 females) with Achilles tendon re-rupture. Median time to re-rupture was 98.5 days (IQR 82-122.5), but 8/48 re-ruptures occurred late (range 3 to 50 years) after primary Achilles tendon rupture. Males were affected more commonly (OR = 7.40, 95% CI 0.91-60.15; p = 0.034). Mean Achilles tendon re-rupture incidence was 0.94/100,000/year for all ages and 1.16/100,000/year for adults (≥ 18 years). Age distribution was bimodal for both primary Achilles tendon rupture and re-rupture, peaking in the fifth decade, with secondary peaks in older age. Incidence of re-rupture was higher in less socioeconomically deprived sub-populations (OR = 2.01, 95%CI 1.01-3.97, p = 0.04). The majority of re-ruptures were low-energy injuries. Greater risk of re-rupture was noted for patients with primary rupture aged < 45 years [adjusted odds ratio (aOR) 1.96; p = 0.037] and those treated with traditional cast immobilisation (aOR 2.20; p = 0.050).

CONCLUSION

The epidemiology of Achilles tendon re-rupture is described and known trends (e.g. male predilection) are confirmed, while other novel findings are described, including incidence of a small but significant number of late re-ruptures, occurring years after the primary injury and an increased incidence of re-rupture in less socioeconomically deprived patients. Younger age and traditional immobilising cast treatment of primary Achilles tendon rupture were independently associated with Achilles tendon re-rupture.

LEVEL OF EVIDENCE

III.

Achilles tendon resting angle is able to detect deficits after an Achilles tendon rupture, but it is not a surrogate for direct measurements of tendon elongation, function or symptoms

PURPOSE

The aim of this study was to investigate how the Achilles tendon resting angle (ATRA), an indirect measurement of tendon elongation, correlates with ultrasonography (US) measurements of the Achilles tendon length 6 and 12 months after an acute ATR and relates to other clinical outcome measurements such as heel-rise height, jumping ability and patient-reported outcome measurements (PROMs).

METHODS

Patients were included following acute Achilles tendon rupture (ATR). Achilles tendon length, ATRA, heel-rise height (HRH), drop countermovement jump (Drop CMJ) and PROMs (Achilles tendon total rupture score (ATRS) and physical activity scale (PAS)) were evaluated 6 and 12 months after injury. Achilles tendon length was evaluated using US, while the ATRA was measured with a goniometer.

RESULTS

Sixty patients (13 women, 47 men), mean (SD) age 43 (9) years, with an acute ATR undergoing either surgical (35%) or non-surgical (65%) treatment were evaluated. A negative correlation (r = - 0.356, p = 0.010) between relative ATRA and tendon elongation was seen at 12 months after ATR. There were also significant positive correlations at 6 and 12 months between relative ATRA and HRH (r = 0.330, p = 0.011 and r = 0.379, p = 0.004). There were no correlations between ATRA and ATRS or ATRA and Drop CMJ, at either 6 or 12 months after the injury.

CONCLUSION

In combination with other clinical evaluations such as HRH and US, ATRA could be a clinical tool for indirect measurements of tendon elongation. However, ATRA cannot be recommended as a direct surrogate for US for determining Achilles tendon length.

LEVEL OF EVIDENCE

III.