Table 1 Overview of usual rehabilitation care (control) and the Back in the Game intervention (experimental). All participants receive usual post-operative rehabilitation care

Name

Usual post-operative rehabilitation care

Back in the Game plus usual post-operative rehabilitation care

Why

Usual care reflects the real-world clinical context. Rehabilitation helps patients recover from surgery, gradually regain knee function, and prepare to return to sport.

Psychological factors such as confidence and anxiety about new injury, have strong influences on returning to sport after serious knee injury.

Rationale: supporting psychological readiness to return to sport, in addition to usual rehabilitation, will help athletes transition back to their sport. A self-directed approach will help target the specific challenges encountered by the individual.

What (materials)

Strength training equipment (e.g. free weights, machine weights, resistance bands, suspension cables), balance training equipment (e.g. BOSU ball) and aerobic training equipment (e.g. treadmill, stationary bicycle) as available in the usual care setting.

All content is provided on-demand through the Back in the Game smartphone application (see https://vimeo.com/345486299/6bba07cc11 for an overview [in Swedish]).

What (procedures)

Usual rehabilitation care for pivoting sports athletes typically comprises 4 phases [22]:

1. Acute phase aimed at reducing pain and swelling, improving knee movement, and recovering performance of activities of daily living (e.g. walking without aids).

2. Intermediate phase aimed at progressing muscle strength sport-specific tasks

3. Late phase

4. Injury prevention phase

The treating clinician and the patient collaborate to decide on the specific therapies and exercises, and the number of face-to-face, home-based and gymnasium-based treatment/training sessions required.

Users receive a notification at least every 2 weeks to complete tasks relevant to their stage of rehabilitation. The intervention is designed to be complementary to patients’ rehabilitation progression.

The 24-week programme is based on cognitive-behavioural therapy principles, and comprises 7 modules:

1. Goal setting

2. Confidence for recovery

3. Confidence for return to sport

4. Confidence for performance

5. Confidence to stay injury-free

6. Support to handle thoughts and emotions related to recovery and return to sport

7. Education about knee injury, recovery, return to sport, and safe sports participation

Who

Physiotherapist plus patient-directed home and/or gymnasium-based sessions

Patient-directed via custom application

How

Typically, individual face-to-face treatment sessions combined with independent sessions at home and/or gymnasium. Some clinicians may provide group rehabilitation sessions.

Internet-delivered (smartphone or desktop application)

Where

Swedish outpatient rehabilitation clinic (either public/primary care or private setting) plus home and/or gymnasium-based programme at a convenient location for the participant.

Users access the intervention on-demand via custom application

When

The duration of rehabilitation is highly varied. Post-operative rehabilitation programmes typically run for at least 6 months, and usually cease by 12 months.

A 24-week programme commencing one week following ACL reconstruction (i.e. in the first post-operative week). Users continue to have access in ‘read-only’ mode from the end of the active intervention period (24 weeks) up to 12 months following ACL reconstruction.

How much

Highly variable. Clinical practice guidelines recommend at least 3–4 sessions per week. In the early post-operative phase, rehabilitation sessions may be short duration and more frequent. In the late phase, rehabilitation sessions may be longer duration (minimum 40 min) and less frequent.

Minimum 30 min recommended training per week over the 24-week programme. Users receive up to 3 SMS reminders per new task.

Tailoring

The treating clinician directs rehabilitation content to focus on specific impairments or functional limitations as appropriate for the patient’s daily living and sport demands. We expect the exercises chosen will be highly variable but will cover the 4 broad rehabilitation phases.

Users choose the cognitive-behavioural therapy task they would like to practice each week from a task menu. Intervention modules are tailored to the progression of rehabilitation (e.g. focus on confidence in recovery during the early rehabilitation phase and confidence to perform well in sport during the late rehabilitation phase).

How well

Participants record how many sessions per week they attend of face-to-face rehabilitation, and how many home-based and gymnasium-based rehabilitation sessions they complete.

The research team will track use usage statistics.