Reconstruction is by using hamstring (semitendinosus and gracilis) tendon graft or BPTB bone patellat tendon bone grafts
The procedure itself involves the drilling of tunnels through the proximal tibia and distal femur, threading the graft and attaching it proximally and distally by one of a number of methods.
The assessment of the patient with anterior cruciate ligament reconstruction involves a review of:
• Isomerism
• Integrity
• Impingement
ISOMERISM
The position of the graft tunnels is important to ensure that the graft functions as the native ligament. Reproducing the complex function of the native graft is difficult particularly as the two separate bundles (the anteromedial and the posterolateral) are at different tensions throughout the range of flexion and extension. In order to reproduce this function as closely as possible, the position of the tibial and femoral tunnels is crucial. Typically the graft is placed using a carefully designed jig which is attached to the knee and the incidence of misplacement of the tunnels is reduced. The position of the tibial tunnels can be assessed on both plain radiography and MRI. Typically the distal end of the femoral tunnel lies at the superior extent of Blumensaatâdt™s line on the lateral view. The tibial tunnel should emerge into the joint in the central third of the tibia also on the lateral view A too anterior position of the tibial tunnel will force the graft to impinge against the intercondylar roof and as a consequence repetitive flexion and extension may lead to rupture.
INTEGRITY
Apart from in the first year, the cruciate graft should return low signal on most MR sequences. Any internal signal chain should prompt to search for impingement which may lead to subsequent tearing of the graft.
IMPINGEMENT
There are two kinds of impingement, roof and side wall. Roof impingement occurs when the tibial tunnel is too far interior and the graft is deflected posteriorly by the leadingPart of the family group. If roof impingement is allowed to persist, the Grafton Road and rupture. Sidewall impingement is less common because this is something that it is easier for the surgeon to detect at the time of operation. Pre-graft osteophyte which may impinged either the native or replacement anterior cruciate can be saved at surgery to ensure that the side wall does not impact the replacement graft
Following meniscal reception, if a small amount of the meniscus has been removed, the same criteria can be implied applied for assessment of recurrent tear, as in the native meniscus. Increased signal within the meniscus reaching an articular surface is sufficient to diagnose a recurrence tear. When more than 50% of the meniscus has been resected it becomes more difficult to apply standard criteria.
It should be noted that when horizontal tears are resected, some residual resist Linear signal may be seen within the meniscal remnant. This does not indicate a re-tear
