(Joint Mice)

An ACL tear most often happens when the knee is suddenly twisted or hyperextended. This can occur during rapid changes in direction, sudden stops, landing awkwardly from a jump, or direct contact to the knee (such as in sports like soccer, basketball, or football). The ligament is stretched beyond its capacity and tears.

Common Terms for the Injury

ACL Tear

ACL Sprain

Torn ACL

Signs and Symptoms

A popping sound at the time of injury

Immediate pain and swelling in the knee

Instability or feeling like the knee will “give out”

Reduced range of motion

Tenderness along the joint line

Common Care and Treatment

Immediate (First Aid / Acute)

Rest and avoid putting weight on the leg

Ice the knee to reduce swelling

Compression wrap to help control swelling

Elevation above the heart level when possible

Short-Term / Clinical

Use of crutches to limit weight bearing

Physical therapy to reduce swelling and regain strength and mobility

Long-Term

Rehabilitation exercises to strengthen quadriceps and hamstrings

Bracing during activity, depending on severity and doctor’s recommendation

Surgical Implication and Diagnostic Evaluation

Diagnostic Evaluation

Physical exam (Lachman test, anterior drawer test)

MRI scan to confirm the extent of the ligament tear

X-rays may be taken to rule out bone injury

Surgical Implication

ACL Reconstruction surgery is common, especially for active individuals or athletes

The torn ligament is replaced with a graft (from the patient’s own tendon or a donor).

Surgery is typically followed by structured physical therapy.

Prognosis and Long-Term Complications

Prognosis

Many patients regain full function with proper treatment and rehab.

Return to sport often takes 6–12 months after surgery.

Long-Term Complications

Knee instability if not properly rehabilitated

Increased risk of osteoarthritis later in life

Possible re-tear of the ACL or injury to other knee structures (meniscus)