Functional and Patient-reported Outcome After Peroneal Tendon Surgery and Different Immobilization Protocols

Pain will be graded using Numeric Rating Scale (NRS) ranging from 0 to 10, whereas 0 is corresponding to no pain and 10 is corresponding to the worst pain imaginable.

Patients will be asked to select a corresponding number (0 - 10) to indicate the pain intensity they are experiencing during an average day, before taking the functional tests, during the tests and after taking the functional tests. In follow-ups that does not include any functional tests, the patients will only grade pain during an average day.

The widest part of the calf will be measured.

Range of motion (ROM) will be measured with inclinometer. Patients will be barefoot. ROM will be measured preoperative and postoperative after 6 weeks, 3 months, 6 months, 12 months and 24 months.

The first two measurements after surgery (6 weeks, 3 months) will be carried out unloaded. The subsequent measurements (6 months, 12 months, 24 months) will be carried out loaded.

The patients balance will be measured with stabilometry.

A biomechanical evaluation of the ankle, knee and hip kinematics and kinetics during walking, running, and jumping will be performed before and after surgery (6 months, 12 months and 24 months). For collection of the data, 16 Qualisys 7+ cameras (Qualisys AB, Gothenburg, Sweden) and 4 force plates will be used. 55 reflectors will be attached on the patient's body to be able to detect segmental movements. Kinetic data will be evaluated in power (watt) in ankle, knee and hip. Comparison will be performed between groups and limbs in power (LSI) - injured side/healthy side *100 expressed in percent. The range in LSI is between 0-100% and the higher value, the better outcome.

EMG electrodes on the medial and lateral Gastrocnemius, Soleus and Tibialis Anterior, Quadriceps and trunk muscles will be attached on the patient in order to measure how the muscles are recruited during walking, running and jumping. Both healthy and injured sides will be analyzed. The electrical activity in the muscles will be evaluated. Comparison will be performed between groups and limbs in power (LSI) - injured side/healthy side * 100 expressed in percent. The range in LSI is between 0-100% and the higher value, the better outcome.

Cutting test will be performed according to standard module.

Ankle plantar flexion endurance and heel-rise height will be evaluated using MuscleLab® during a heel-rise work test.

During all follow-ups (including preoperative) the patients will fill out questionnaires. The questionnaires contain questions concerning, for example, fear of physical activity, fear of re-injuring oneself, satisfaction with the treatment, whether they have experienced complications, time on sick leave, etc.

SEFAS is a questionnaire designed to evaluate disorders of the foot and ankle.

The score covers different constructs that are not reported separately in subscales: pain, function including limitations of function, and other symptoms. Each of the 12 multiple-choice questions is scored from 0 to 4; thus, 0 total points represents the most severe disability and 48 represents normal function.

The FAOS is a patient-reported foot- and ankle-specific questionnaire including 42 items in 5 subscales evaluating pain, symptoms, function of daily living (ADL), function in sport and recreation, and quality of life (QOL). Standardized answer options are provided, and each question is rated on a scale from 0 to 4. A score is calculated for each subscale after which raw scores for each subscale are transformed to a scale ranging from 0 to 100 and presented graphically as the FAOS profile. The minimum possible total score for each subscale is 0 points, a condition that represents the most severe disability, whereas the maximum of 100 points represents normal ankle function.

Physical activity questionnaire. A patient reported outcome used fot the purpose to evaluate the patients self estimated physical activity level. The scale is from 1 to 6 and the higher score, the better outcome.

Descriptive system comprises the following five dimensions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. Each dimension has three levels: no problems, some problems, and extreme problems. The EQ-5D index is a weighted total value of the score that is calculated after being adjusted for cultural differences.

The answers given to EQ-5D permit to find 243 unique health states or can be converted into EQ- 5D index an utility scores anchored at 0 for death and 1 for perfect health.