Anterior Knee Pain
The most common complication of ACL surgery ispain around the kneecap.
These patients can even have complications such aspatellar fractureandpatellar tendon tear, although these are very uncommon.
However, patients having hamstring grafts or donor grafts can also have symptoms of anterior knee pain.

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Anterior knee pain is thought to result from altered joint mechanics and can often be overcome with physical therapy.
It’s important for athletes to adhere topostoperative rehab protocolsto ensure their knee mechanics improve.
Stiffness (Arthrofibrosis)
Stiffness in the knee joint is common after ACL surgery.
Fortunately, most patients with stiffness can address this complication with aggressive rehabilitation.
In the past, doctors used specialized machines to bend the knee, calledCPM machines.
However, these machines have not been shown to lead to long-term improvement.
But even after reconstruction surgery, instability of the knee may still be an issue.
However, in some cases, post-surgical instability is present even after successful surgery and rehabilitation.
A sensation of theknee giving outis a common complaint of those dealing with knee instability.
However, studies are revealing possible ways to prevent and improve instability after reconstruction surgery.
Graft Stretching
When an ACL is reconstructed, the ACL is replaced by an autograft or allograft.
An autograft is a transfer of bone or tissue from one part of a patient’s body to another.
An allograft is a transfer of bone or tissue from a donor or cadaver.
The reason for bleeding after ACL surgery varies and is usually resulting from an underlying issue.
Disease Transmission
Infection is a rare complication but can be serious when it occurs.
When the infection is inside the knee joint, there is a concern about theACL graft becoming infected.
ACL grafts are very strong.
That is whycompetitive athletesoften choose to use their own tissue, even though rehab may be more difficult.
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