Blood Flow Restriction Exercise in Patients With an Achilles Tendon Rupture

Patient's ability to perform a Single-Leg Heel-rise, defined as the ability to raise the heel of the injured leg at least 2 cm while keeping the knee straight. The test is performed with patients standing on a flat surface with the ankle in a neutral position. Patients will be allowed to keep their balance by lightly touching a wall.

The ATRS is a validated patient-reported, injury-specific questionnaire regarding physical activity and symptoms. The ATRS consists of 10 items scored from 0 (major limitations) to 10 (no limitations), resulting in a score between 0 (worst) to 100 (best).

The unilateral 30 second Sit to Stand test (unilateral 30STS) is a clinical test of lower extremity function. The unilateral 30STS tests how many correct repetitions of a sit to stand from a chair, a patient can complete in 30 seconds

The calf circumference is measured in centimeters (cm) on both legs using a tape measure 15 cm below the medial palpable joint line of the knee. Repeated measurements will be made until a consistent measurement is found.

Thigh circumference is measured in centimeters (cm) on both legs using a tape measure 10 cm proximal to the apex patella. During measurement patients lay supine on an examination table with knees bent in a 90-degree angle.

The Achilles tendon length is indirectly measured by the Achilles tendon resting angle (ATRA), measuring the difference in passive dorsiflexion when lying prone with knees in a 90-degree angle.

Patient's maximum heel-rise height measured in cm. The test is performed with patients standing on a flat surface with the ankle in a neutral position. Patients will be allowed to keep their balance by lightly touching a wall.

The maximal number of correct single-leg heel-rise repetitions is measured. The test is performed with patients standing on a flat surface with the ankle in a neutral position. Patients will be allowed to keep their balance by lightly touching the wall.

The TSK-13 is a 13-item self-reported measure for fear of movement or reinjury, that has previously been used in patients with Achilles tendon rupture.

The IPAQ-SF consists of 7 items on physical activity as time spent performing vigorous and moder-ate activities, the time spent walking, and time spent sitting during the past week. The IPAQ pro-vides an estimate of the total weekly physical activity measured in MET-minutes per week and total minutes spent sitting.

The number of adverse events and serious adverse events will be recorded and reported to a Data Safety Monitoring Board. Adverse events are defined as unexpected medical events related to the initial treatment. Serious adverse event are complications requiring further inpatient care, such as re-rupture of the Achilles tendon, non-union of the Achilles tendon, or deep venous thromboembolism and pulmonary embolism. Muscle soreness or mild pain following exercise is expected and not con-sidered an adverse event.

Patients are asked on a questionnaire whether they think their current symptom state is satisfactory (yes/no).

Perceived effect of intervention is rated on a 7-point likert scale from significantly worse to significantly better.

Patients' adherence with the exercise sessions (completed sessions) and progression during the intervention period will be recorded in self-reported exercise diaries by the patients. Exercise diaries will also be provided to patients in the control group, to monitor usual care exercise.

Descriptive demographic data.

The pressure required to fully occlude arterial inflow to the working limb will be measured. 80% of the total occlusion pressure will be calculated and applied during exercise.

Number of participants who drop out from the trial during the study-period.

Exercise diaries detailing what exercises are performed during usual care after hospital treatment.

The EQ-5D-5L is a generic self-reported measure for health-related quality of life consisting of five dimensions (mobility, self-care, usual activities, pain/discomfort, and anxiety/depression) with five severity levels each. The total score of the descriptive index and EuroQol Visual Analogue Scale (EQ-VAS) ranges from -0.624 (worst) to 1.000 (best) and 0 (worst imaginable health) to 100 (best imaginable health), respectively.