1. Abdominal stabilization progression for TFR is applied to all cases with simultaneous breathing exercises for 8 weeks (24 sessions in total) (8). Exercises are performed 3 days a week, 45 minutes a day, starting from warm-up and recumbent position respectively, and the intensity is adjusted individually by observing tone and motivation.

The experimental group's routine physiotherapists also gave them a conventional rehabilitation program (the same protocol as in the active comparison arm) for 40 minutes per day, 2 days per week.

The control group is the group that receives conventional treatment 2 days a week, 40 minutes per session.

Conventional Rehabilitation Program Content: All sessions include the following rehabilitation program, supervised by a physiotherapist and individualized according to tolerance. Number of exercise repetitions: 10-20. The intensity is adjusted by observing motivation.

Abdominal stabilization progression for TFR is applied with simultaneous breathing exercise for 3 days a week, 45 minutes a day, 8 weeks (24 sessions in total)(8).

1. Basic Abdominal Stabilization Training, Task-Focused Exercises (without spinal diagonal and rotational components)(8,12).

   Warm-up: 5 minutes, Global Stretching and Relaxation(9,10,11). Extremity load, elastic band, and unstable surface are added as stabilization is achieved in neurodevelopmental positions. Task-oriented exercises(12).

   Cooling Down: Warm-up exercises are repeated.

2. General Posture and Asymmetry Training Brochure (includes adolescent, family, and team members)(13-17).

The exercise starts with 3 seconds and gradually progresses to 10 seconds, 10 repetitions, and 3 sets.

The TFR group also receives Conventional Treatment 2 days a week, 40 minutes per day, for 8 weeks. The same treatment protocol is applied as the control group). Routine physiotherapists apply conventional treatment.

Trunk Impairment Scale: It consists of coordination, dynamic and static sections. In the static section, the responses in actively and passively crossing the legs with the feet in a supported position are recorded. In the dynamic section, unilateral hip movements and lateral flexion of the trunk are evaluated. In the coordination section, the upper and lower body are asked to move. Coordination consists of dynamic and static sections. The maximum scores that can be obtained from the tests are 7 for the static section, 10 for the dynamic section, and 6 for the coordination section. The score range is 0-23. The total score for TIS ranges between 0 for a minimal performance to 23 for a perfect performance.

Spinal Mobility and Alignment Assessment (Sagittal Plane): Spinal Mouse (SM) measurements are taken at the same time of day, in an environment where the patient is resting, distrubating their weight equally between their two feet as much as possible, and standing symmetrically, while the patient is standing upright in an anatomical position, by moving downwards at a constant speed over the SM spinal criterion points (from C7 spinous process to S3) by the physiotherapist. The spine is measured 3 times in the sagittal plane. The average value of the measurements is used for analysis.

Jebsen Taylor Hand Function Test (JTHFT): Writing, card turning, picking up small objects, large and heavy objects skills and durations are assessed in both hands. 7 items are repeated for both hands. The completion time of each task is recorded separately. The score for the subtest is equal to the time in seconds required to complete the task, the maximum score for the subtest is 120. The total score is equal to the sum of points for all subtests and is calculated separately for each hand. The lower the score, the better the child's hand function.

The 1-minute walk test (1-MWT) is a valid and simple assessment for monitoring changes in walking capacity in children with chronic conditions. While performing the 1-MWT, children are asked to walk as fast as they can on a circular track. Running is prohibited. They may use mobility aids if necessary. The distance they travel on the track is recorded.