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Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
Published on: May 1, 2018
Acute painless shoulder weakness during high-intensity athletic training.
Tyler Vachon1, Michael Rosenthal, Christopher B Dewing
1Naval Medical Center San Diego, Department of Orthopaedic Surgery, San Diego, CA 92134-1112, USA.
The American Journal of Sports Medicine
|January 7, 2009
Summary
Intense physical training can cause brachial plexus injuries, leading to rare painless shoulder weakness in Navy trainees. Early diagnosis and rehabilitation are key for recovery and return to duty.
Area of Science:
- Sports Medicine
- Neurology
- Occupational Health
Background:
- Repetitive athletic activities can cause brachial plexus injuries.
- Painless shoulder weakness is a rare symptom of these injuries.
Purpose of the Study:
- To present physical examination and electrodiagnostic findings in Navy trainees with acute painless shoulder weakness.
- To detail treatment and return-to-duty timelines for these injuries.
Main Methods:
- A case series of 11 US Navy special warfare trainees with acute painless shoulder weakness.
- Inclusion criteria: onset <3 weeks, no prior shoulder injury.
- Methods included serial examinations, electrodiagnostic testing, and rehabilitation.
Main Results:
- All trainees showed weakness in flexion and abduction.
- Electrodiagnostic studies confirmed C5-6 brachial plexus injury (axillary, suprascapular, musculocutaneous nerves).
- Mean recovery time was 21 weeks; 6 of 11 completed training.
Conclusions:
- Upper brachial plexus injuries in intense training can manifest as painless shoulder weakness.
- This condition can be debilitating, impacting military readiness.
- Findings offer guidance for future training principles and injury prevention.
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