Training eccentric external rotator strength is a prominent goal in shoulder rehabilitation. The external rotators need to be able to counter the strong internal rotators during throwing. In training or playing a match, actions like throwing, smashing, serving and so on, will result in strength increase of the internal rotators but not necessarily of the external rotators. A hypothesis for injury is the imbalance between concentric internal rotator strength and eccentric external rotator strength. The ratio between both strength values should approximate 1, meaning that eccentric external rotator strength should equal concentric internal rotator strength when measured at 90° abduction. A suggestion for progression of eccentric external rotator strenght training is presented with increasing challenge for stabilisation.
Exercise 1: Supine eccentric external rotation
- Before start, patient tilts scapula posteriorly in a way that a large part of the posterior scapular surface is in contact with the floor. He/she should not loose pelvic stabilisation and maintain some posterior tilt of the pelvis with contraction of the abdominal muscles.
- Next homolateral leg is flexed to take off the load from the theraband for the concentric phase
- Shoulder is brought to 90° abduction and external rotation, upper arm is supported on the floor (or towel roll when necessary to align humerus with scapula depending on your patient)
- Homolateral leg is extended to load the theraband
- Patient then slowly (5-7 seconds) moves the hand towards internal rotation
- At end range internal rotation, stabilisation of the scapula becomes more challenging. When it is no longer possible to keep the posterior surface of the scapula on the floor patient has reached the end of the movement.
Exercise 2: Supine eccentric external rotation with active glenohumeral stabilisation
- In the next progression we challenge the patient to actively stabilize the shoulder axis of rotation that runs through the humerus. The therapist can place one finger onto the olecranon showing the patient the axis of rotation that needs to stay in place.
Exercise 3: Standing eccentric external rotation with active scapular stabilisation
- Next progression in standing is more specific as this is the position in which throwing athletes use eccentric deceleration strength.
- Standing will activate shoulder abductors, working against gravity to keep the arm 90° abducted.
- There is no longer the feedback from floor contact for scapular stabilisation in posterior tilt so patient needs to switch to internal proprioceptive feedback.
- Again focus on maintaining axis of rotation of the humerus with the olecranon fixed at 1 point in space.
Exercise 4: Unipedal standing eccentric exernal rotation with active core stabilisation
When performed in unipedal stance, knee flexed and trunk bent over, the patient is ultimately challenged to not only stabilize at the glenohumeral and scapular level but in addition maintain balance and stabilize the core.
Written by: Annelies Maenhout