The investigators hypothesize that a single injection of platelet-poor plasma (PPP) into an acute muscle injury will significantly improve local muscle regeneration and patient outcomes compared to the standard of care using only ultrasound-guided hematoma aspiration. Muscle regeneration will be assessed through quantitative MRI analysis. The investigators anticipate that PPP injections will lead to a measurable reduction in scar tissue and an increase in regenerated muscle tissue at the injury site over a six-month period.

Inclusion Criteria:

• Age between 18 and 45 years
• Diagnosis of a muscle strain in the lower extremities, including but not limited to hamstring, quadriceps, and gastrocnemius
• Injury occurred within 10 days of the initial clinical evaluation
• Injury occurred while engaging in athletic or sporting activities
• Participants must be willing to undergo prescribed physical therapy
• Participants have agreed to standard-of-care management for their injury, which may include ultrasound-guided aspiration with or without a platelet-poor plasma injection

Exclusion Criteria:

• Previous injection at the injury site.
• Pregnant or breastfeeding women, or women who may become pregnant during the study duration
• Injuries resulting from puncture or crush trauma
• Injuries occurring more than 10 days prior to the injection date
• Injuries not caused by athletic or sporting activity
• Previous muscle injury in the same muscle group within 6 months