A patient injures the medial collateral ligament with tenderness to palpation, minimal bruising, mild effusion, and a negative valgus stress test. Which grade of sprain does this most likely indicate?

• A. Grade I sprain
• B. Grade II sprain
• C. Grade III sprain
• D. Complete rupture

Answer: (A)

Grading a medial collateral ligament (MCL) sprain is based on how much tearing occurred and whether the knee remains stable to a valgus load. A Grade I sprain means only minimal tearing or stretching of the fibers with no significant laxity, so the joint stays stable when tested.

Here, tenderness along the MCL with only minimal bruising and a mild effusion fits a mild tissue injury. The key detail is the negative valgus stress test, which shows there is no abnormal medial instability. That combination points to a mild sprain where the ligament is damaged but still functioning well, i.e., a Grade I sprain.

If the injury were more severe, you’d expect a positive valgus test with noticeable laxity (Grade II) or even gross instability with complete rupture (Grade III). Management would escalate accordingly, but with these findings, conservative care and gradual return to activity are typical.