Medically reviewed by Amy Kwan, PT Key Takeaways Lower back and hip pain can be caused by injuries like muscle strains and overuse from repetitive movements.Arthritis is a common cause of one-sided ...

A muscle spasm — also known as a charley horse, muscle cramp or twitch — is a sudden, involuntary movement in one or more muscles. Common causes include stress, exercise, or dehydration, but nerve ...