Brief Answer:
Muscle Sprain

Detailed Answer:
hi,

thanks for your question. if your X-rays were normal then a muscle sprain or tear is an explanation for your ongoing symptoms.

Typically, people with a strain experience pain, muscle spasm and muscle weakness. They can also have localized swelling, cramping, or inflammation and, with a more severe strain, some loss of muscle function. Patients typically have pain in the injured area and general weakness of the muscle when they attempt to move it. Severe strains that partially or completely tear the muscle or tendon are often very painful and disabling.

Grade I Strain: This is a mild strain and only some muscle fibers have been damaged. Healing occurs within two to three weeks.
Grade II Strain: This is a moderate strain with more extensive damage to muscle fibers, but the muscle is not completely ruptured. Healing occurs within three to six weeks.
Grade III Strain: This is a severe injury with a complete rupture of a muscle. This typically requires a surgical repair of the muscle; the healing period can be up to three months.

The treatment of muscle sprains and strains has two main goals. The first goal is to reduce swelling and pain; the second is to speed recovery and rehabilitation.
To reduce swelling it is recommended to follow use R.I.C.E. therapy (Rest, Ice, Compression and Elevation) for the first 24 to 48 hours after the injury.

An over the counter (or prescription) anti-inflammatory medication may also help decrease pain and inflammation.

The second stage of treating a sprain or strain is rehabilitation to restore normal function. When the pain and swelling are reduced you can generally begin gentle exercise. A custom program is often created by a physical therapist that prevents stiffness, improves range of motion, improves flexibility and builds strength. Depending on the type of injury you have, you may go to physical therapy for several weeks, or do the exercises at home.

I hope this answers your question

best wishes

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