Locked Knee
In the absence of reliable evidence, it is the opinion of the work group that patients with an ACL tear and a locked knee secondary to a displaced meniscal tear have prompt treatment to unlock the knee in order to avoid a fixed flexion contracture.

Rationale
There were no published studies that met the criteria for this recommendation. The work group felt that, if left untreated for a sufficient period of time, a locked knee may lead to a fixed flexion contracture that may no longer be recoverable and could thus threaten the functional viability of the leg.

The torn meniscus is also more likely to be repairable if the meniscus is reduced early. Prolonged knee flexion may lead to articular cartilage damage as well.

Potential Harms of Implementation
As with all surgical procedures, there are patient risks including but not limited to infection, anesthetic complications, phlebitis, neurovascular injury, meniscal repair failure, and ACL reconstruction failure.

Future Research
Evaluation of the relative risk of arthrofibrosis if the ACL is reconstructed at the same time or as a staged procedure
 
 

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