Revision ACL reconstruction
Failure of anterior cruciate ligament reconstruction is thankfully uncommon however the rate of failure is somewhere between 3 and 10% in the orthopaedic literature Grafts can fail due to either technical problems with the first operation or due to a further injury to the same knee. A reconstructed ACL is very strong once it has fully healed but can be injured during the rehabilitation period and this is why return to contact sports is not recommended for 5-6 months post surgery.
Following the rehabilitation you are as likely to tear your opposite native cruciate as you are the graft but a big enough injury can cause graft rupture.
If your knee becomes unstable and you cannot return to sports/activities a revision (redo) reconstruction may be needed.
The choice of graft for revision surgery will depend on several factors including which graft was used for the first surgery, the size and location of the bone tunnels and patient factors such as occupation, ongoing sites of knee pain and combined ligament injury.
The mainstay of grafts used for revision ACL are native (autograft) patella tendon (BTB) or hamstrings or cadeveric (donated allograft) achilles tendon or patella tendon.
The surgery is usually performed as a day case or single overnight stay. Key hole techniques are used to clear the old graft tissue away, the previous hardware is removed if necessary and the bone tunnels are either re drilled or new tunnels are created. Injury to the cartilage washers (meniscus) and bearing surface can be addressed at the same surgery.
Rehabilitation is very similar to a primary ACL reconstruction and the aim is to return to all activities by 6 - 9 months post surgery