Early Mobilization After Achilles Tendon Rupture

Study Overview
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Brief Summary
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The purpose of this study is to determine whether early mobilization after Achilles tendon rupture can speed up healing, prevent development of venous thromboembolism and improve patient outcome.

Detailed Description
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Patients with acute Achilles tendon rupture will be screened for eligibility at the Karolinska University Hospital and Södersjukhuset, Stockholm. One hundred-fifty patients will be included and enrolled and assigned to the interventions either by a third party nurse or by a research nurse. Randomisation will be performed with use of computer-generated random numbers in permuted blocks of four, through an independent software specialist, and consecutively numbered, sealed, opaque envelopes opened after surgery and prior to treatment. The patients will be randomized to undergo either treatment as usual using plaster cast treatment alone or direct post-operative functional mobilization with a weight-bearing orthosis with adjustable range of motion of the ankle. The power calculation was based upon data from a recent study reporting a 50% rate of CDU-verified DVT after ATR surgery (Domeij-Arverud et a. 2015). We estimated early functional mobilization (EFM) to confer a 50% risk reduction. Sixty-three patients in each group were required to detect a difference of 25% in the incidence of DVT (two-sided type-I error rate = 5%; power = 80%). We decided to include 150 patients to counteract drop-outs. On recommendations from the ethical committee, a ratio of 2:1 was chosen, since our hypothesis was that the EFM group would perform better. The endpoint of the first part of the study is tendon healing quantified at 2 weeks by microdialysis followed by quantification of markers for tendon repair. The sample size for the outcome in the microdialysis study was calculated on a difference of the glutamate metabolite of 12 µM between the two groups. For this power analysis, we used a glutamate standard difference of 15 µM resulting from a previous study. It was determined that a sample size of 25 patients per group would be necessary to detect the glutamate difference with 80% power when alpha was set equal to 5%. Anticipating that we would lose 10% of participants enrolled, we plan to enroll 27 patients in each group for microdialysis. The primary aim of the short-term follow up of this randomized, controlled trial was to assess the efficacy of EFM to reduce the DVT incidence after ATR surgery, at two and six weeks post-operatively, compared to treatment-as-usual, i.e. two weeks of plaster cast followed by four weeks' orthosis immobilization. The secondary aim was to evaluate the effect of patient intrinsic factors (age, BMI, calf circumference, ankle range of motion, pain and fear of movement) and patient extrinsic factors (amount of weightbearing, number of daily steps) on the risk of sustaining a DVT. The primary aim with the long-term follow up is to investigate the effect of early postoperative functional mobilization compared to immobilization on patient-reported function, health, fear of movement, physical activity level, and differences in functional capacity. The second aim is to explore if the occurrence of DVT postoperatively effects functional outcome in the long-term after surgical treatment of ATR. Additional aims: The primary aim of the second part of this study was to assess the number of steps and the amount of loading in a weight bearing orthosis during the first six weeks post-surgical ATR repair. A secondary purpose was to investigate if the amount of loading was correlated to fear of movement or/and pain. The aim with this substudy is to describe differences between the two groups over time regarding tendon elongation, differences in muscle cross-sectional area and differences in tendon cross-sectional area (on the injured side) and to examine if the differences can predict functional outcome in the long-term and if any of the follow-up occasions are most important for long-term functional outcome. Few studies have evaluated outcome more than one year after injury. The aim of this substudy is to investigate differences in outcome at 3 years after injury between the patients that sustained a DVT and those who did not sustain a DVT. Another aim is to compare the two intervention groups over 3-years time.

Official Title
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Effects of Direct Functional Mobilization After Achilles Tendon Rupture on Healing and Outcome

Conditions
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Achilles Tendon Rupture, Deep Venous Thrombosis

Intervention / Treatment
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* Device: VACOped orthosis
* Device: Plaster cast


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Acute unilateral ATR, operated on within 96 hours Age between 18 and 75 years Exclusion Criteria: Inability to give informed consent Current anticoagulation treatment (including high dose acetylsalicylic acid) Planned follow-up at other hospital Inability to follow instructions Known kidney failure Heart failure with pitting oedema Thrombophlebitis Thromboembolic event during the previous three months Other surgery during the previous month Known malignancy Haemophilia; and pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Early mobilization<br>Functional mobilization initiated directly post-operative with a weight-bearing VACOped orthosis with adjustable range of motion of the ankle | Device: VACOped orthosis<br>* Weight-bearing orthosis with adjustable range of motion of the ankle<br>|
| Active Comparator: Immobilization<br>Treatment as usual using plaster cast immobilization | Device: Plaster cast<br>* Lower limb plaster cast<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Deep venous thrombosis (DVT) | At 2 and 6 weeks postoperatively the number of participants with DVT will be assessed by compression duplex ultrasound (CDU) | Six weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Functional outcome - muscular endurance tests (heel-rise) | The functional outcome will be assessed at 26 and 52 weeks and 3-4 years postoperatively by validated muscular endurance test, i.e. heel rise test. | Four years | 
| Patient-reported outcome - ATRS | The patients' symptoms will be assessed using the reliable and valid score; the Achilles tendon Total Rupture Score (ATRS). 6, 12 months and 3-4 years postoperatively | Four years | 
| Patient-reported outcome - EQ-5D | The patients' symptoms will be assessed using the reliable and valid score; EuroQol Group's questionnaire (EQ-5D). | One year | 
| Physical activity - PAS | The patients' physical activity levels will be assessed a valid score; the Physical Activity scale (PAS). 6, 12 months and 3-4 years postoperatively | Four years | 
| Patient-reported outcome - The Foot and Ankle Outcome Score (FAOS) | The patients' symptoms will be assessed using the reliable and valid score; The Foot and Ankle Outcome Score. FAOS consists of 5 subscales; Pain, other Symptoms, Function in daily living (ADL), Functioning sport and recreation (Sport(Rec), and foot and ankle-related Quality of Life (QOL). Each question gets a score from 0 to 4. A normalized score (100 indicating no symptoms and 0 indicating extreme symptoms) is calculated for each subscale. Assessed 6 and 12 months postoperatively | One year | 
| Patient-reported outcome - RAND 36 Health and Quality of Life questionnaire | The patients' symptoms will be assessed using the reliable and valid score; The RAND-36 Health and Quality of Life. The questionnaire is composed of 36 items, scored from 1 to 2,3, 5 or 6, some items are scored reversed. The score is divided in 8 subscales (dimensions) as the SF-36 questionnarie. The software recodes the points to a scale of 0 (worst) to 100 (best) for each subscale. Assessed at 6 and 12 months postoperatively | One year | 
| Patient-reported outcome - Tampa Scale of Kinesiophobia, Swedish version, TSK-SV | The patients' symptoms will be assessed using the reliable and valid score; The Tampa Scale of Kinesiophobia-SV. The scale comprises of 17 items and a total score is computed. 4 items are inverted and rescaled Before summation. Each item are scored from 1 (strongly disagree) to 4 (strongly agree). The total sum is between 17 to 68, where a score of more than 37 is defined as kinesiophobia. Assessed at 2 and 6 weeks and 6 and 12 months postoperatively | One year | 
| Plantar force loading | Measured with mobile force sensors, insoles at 2 and 6 weeks postoperatively | Six weeks | 
| Patient-reported diary - self-reported loading | Estimation on daily self-reported loading on a VAS-scale, scored from 0 (non-weightbearing) to 100 (full weightbearing). Performed at home during the first 2 weeks postoperatively. The VAS scale is converted to percent (%) for analysis. | Two weeks | 
| Patient-reported diary - pain ratings | Pain ratings on a VAS-scale at home during the first week postoperatively. The patients are rating their pain from 0 (no pain) to 100 (worst imaginable pain) during activity and at rest. | Two weeks | 
| Patient-reported diary - steps/day | Measurement of number of steps taken each day with a valid pedometer at home during the first 2 weeks postoperatively | Two weeks | 
| Calf circumference | Measured with a tape measure at the thickest part of the calf in sitting position at 2 and 6 weeks and 6, 12 months and 3-4 years postoperatively | Four years | 
| Ankle dorsiflexion | Ankle range of motion in dorsiflexion, measured in sitting position with goniometer at 2 and 6 weeks postoperatively | Six weeks | 
| Tendon length measurement | Ultrasound measurement on Achilles tendon length, measured in centimeters, from the calcaneal bone to the gastrocnemius and the soleus muscles, with extended field-of-view images. Images taken at 2 and 6 weeks and 6 and 12 months and 3-4 years postoperatively | Four years | 
| Tendon thickness measurement | Ultrasound measurement on Achilles tendon circumference (thickness), measured in cm2, with B-mode images. Images taken at 2 and 6 weeks and 6 and 12 months postoperatively | One year | 
| Muscle volume of the calf muscles | Ultrasound measurement on muscle volume of the calf muscles (gastrocnemius), measured in cm2, with extended field-of-view images. Images taken at 2 and 6 weeks and 6 and 12 months postoperatively | One year | 
| Thickness of the calf muscles | Ultrasound measurement on thickness of the calf muscle (soleus). Measured in centimeter, with B-mode images. Images taken at 2 and 6 weeks and 6 and 12 months postoperatively | One year | 
| Achilles Tendon resting angle (ATRA) | A clinical measurement of indirect Tendon length with patient prone lying, measured with goniometer with arms parallell to fibula and MTP5, measured at 2 and 6 weeks and 6 and 12 months and 3-4 years postoperatively | Four years | 
| 3D gait analysis | Three-dimensional gait analysis, performed at 8 weeks and 6 months postoperatively, measurement of the quality of gait | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Microdialysis, Patient related outcome, Heel rise test, Immobilization, functional mobilization, Ultrasound