Eccentric or Concentric Contralateral Training in Rehabilitation After Shoulder Surgery With Elbow Immobilization

The study is structured into four visits:

• Inclusion Visit (V0): During the pre-surgical consultation, patients are informed about the study and provided with an information sheet and consent form.
• Pre-Surgery Visit (V1, PRE): Conducted within 7 days before surgery, this visit includes baseline measurements on both arms (immobilized and non-immobilized). Assessments include:

• Isometric maximal voluntary strength of elbow flexors and extensors using an isokinetic dynamometer.
• 1-RM (one-repetition maximum) for elbow flexors and extensors.
• Arm circumference at 5, 10, and 15 cm from the elbow crease.
• Anatomical cross-sectional area of arm muscles using ultrasound.
• Forearm circumference at 5 cm from the elbow crease.
• Handgrip strength (finger flexors).
• Functional scores: DASH (Disabilities of the Arm, Shoulder, and Hand), Constant-Murley, joint position sense (proprioception), and muscle stiffness.
• Following surgery, patients enter a 4-6 weeks' immobilization period, during which they are randomly assigned to one of three groups:

• Control Group (CTRL): Receives standard care, including rehabilitation sessions three times per week.
• Eccentric Training Group (EXC): Performs standard care plus eccentric training of the non-immobilized arm.
• Concentric Training Group (CON): Performs standard care plus concentric training of the non-immobilized arm.

The training protocol involves 3 sessions per week, separated by 24-48 hours. Each session includes 4-6 sets of 10 repetitions of elbow flexion/extension exercises on the non-immobilized arm at 60-90% of 1-RM, depending on the week. Eccentric or concentric actions are performed based on group assignment, with controlled contraction duration (4 seconds) using a metronome. Rest periods of 2 seconds between repetitions and 2 minutes between sets are provided.

• Follow-Up Visits:

• V2 (POST): At the end of immobilization, the same measurements as V1 are repeated
• V3 (POST + 6 weeks): Measurements are repeated again.
• V4 (POST + 17 weeks): Measurements are repeated again.

Inclusion criteria

• Adult patient (≥ 18 years old) undergoing shoulder surgery (i.e., Bankart procedure, rotator cuff repair, arthroplasty)
• With an indication for immobilization, expected to last 4 to 6 weeks
• Free from any neurological pathology
• Having provided their informed consent before any participation in the research

Exclusion criteria

• Having a medical contraindication to the practice of physical and sports activities
• Presenting an expected modification of their physical activity of the non-immobilized limb
• Having suffered an injury to the upper limbs in the last 6 months
• Having already undergone surgery on the upper limbs
• Pregnant, parturient, and breastfeeding women
• Presenting a medically established alteration of their cognitive functions
• Subject under guardianship, curatorship, family empowerment, or judicial safeguard
• Not affiliated or beneficiary of health insurance coverage
• Any other reason that, in the investigator's opinion, could interfere with the evaluation of the study objectives