How to evaluate a hamstring strain (muscle injury)?

From the Guidelines

To evaluate a torn hamstring, it is essential to prioritize rest and limiting the use of the injured extremity, as well as applying cold therapy to decrease pain and swelling, as recommended by the 2024 American Heart Association and American Red Cross guidelines for first aid 1. When evaluating a torn hamstring, it is crucial to assess the injury through a comprehensive approach.

• The RICE protocol can be applied: Rest the affected leg, apply Ice for 15-20 minutes every 2-3 hours, use Compression with an elastic bandage, and Elevate the leg when possible.
• Note the location and severity of pain, any bruising or swelling, and your ability to bear weight or move the leg. A healthcare provider should evaluate moderate to severe injuries, especially if you heard a popping sound, have significant pain, cannot walk, or see substantial bruising, as they will likely perform a physical examination, testing range of motion and strength, and may order imaging such as an ultrasound or MRI for severe cases, as cold application has been shown to improve pain scores and edema in the acute time period, but not function or time to recovery 1. Hamstring tears are graded from 1 (mild strain) to 3 (complete tear), and proper evaluation is crucial as returning to activity too soon can lead to re-injury and chronic problems.
• Grade 1 injuries typically heal with conservative treatment in 1-3 weeks,
• while grade 3 tears may require surgical intervention and 3-6 months recovery. It is also important to note that cold therapy should be limited to 20 to 30 minutes for 3 to 4 times daily, and ice should not be placed directly on the skin to prevent cold injury, as recommended by experts 1.

From the Research

Evaluation of a Torn Hamstring

To evaluate a torn hamstring, the following steps can be taken:

• Magnetic resonance imaging (MRI) remains the gold standard for diagnosis and may help guide treatment 2
• Patients may present with ecchymoses, pain, and weakness, and the location and severity of the injury can be assessed through physical examination and imaging studies
• The specific tendon(s) injured, tear location, severity, and chronicity can be evaluated to determine the best course of treatment

Treatment Options

Treatment options for a torn hamstring include:

• Nonoperative measures such as activity modification and physical therapy, which can be successful in managing many hamstring injuries 2
• Platelet-rich plasma (PRP) injections, which have shown conflicting evidence regarding their effectiveness in reducing recovery time and improving outcomes 3, 4, 5, 6
• Operative treatment, which is traditionally reserved for 2-tendon injuries with >2 cm of retraction, 3-tendon injuries, or injuries that do not improve with 6 months of nonoperative management 2

Considerations for Treatment

When considering treatment options, the following factors should be taken into account:

• The location and severity of the injury, as well as the patient's overall health and activity level
• The potential benefits and risks of each treatment option, including the use of PRP injections
• The need for a comprehensive rehabilitation program to promote healing and prevent reinjury 2, 6