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Knee
The ACL is a central knee ligament that helps control front-to-back motion and pivot stability. Tears often happen with cutting, landing, or a sudden deceleration, sometimes with an audible pop.
A pop, rapid swelling, and a sense that the knee gave way are classic early signs.
Later, people notice instability with cutting, pivoting, or uneven terrain, even when straight-line walking feels acceptable.
Pain can settle while instability remains, which is why function testing matters after the acute phase.
The ACL does not heal reliably in its native form for many complete tears, especially when fibers are separated.
Associated meniscus and cartilage injuries are common and influence both operative and nonoperative plans.
Some lower-demand patients stabilize well with rehab. Pivot athletes more often discuss reconstruction.
Mechanism, effusion, Lachman and pivot-shift testing, and associated structure exam guide the visit.
MRI confirms tear pattern and looks for meniscus or bone bruise patterns.
We talk through sport goals, occupation, and timing before any surgical pathway.
Early care focuses on swelling control, motion recovery, and quadriceps activation with expert physical therapy.
Shared decision-making covers nonoperative rehab versus reconstruction based on age, sport, and instability.
Adjunct joint procedures are secondary. The ligament decision drives the plan.
No. Some people meet their goals with rehab. Cutting and pivoting sports more often lead to reconstruction discussions.
Rapid swelling after an ACL tear often reflects bleeding into the joint from the injury.
Often yes, after calming the knee and restoring motion, as long as instability is not repeatedly damaging the joint.
ACL injuries more often cause pivot instability and rapid effusion. MCL injuries are medial-sided and frequently heal without surgery.
Dr. Adam Nessim, interventional spine physician, Westport Longevity, Pain & Performance.
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