Anterior Cruciate Ligament Reconstruction

What is ACL knee reconstruction?
It is a surgical procedure that the torn ACL is replaced by another one.

Why ACL tear requires a reconstruction?
There is no place for ACL suture so the ligamentplasty is a necessity.

Which graft is suitable in ACL reconstruction?
Grafts used in such cases are called autografts (taken from the same patient during the procedure) allografts (taken from donors plus radiation) and synthetics.

 

 

 


Graft configuration


Graft fixation

What is the synthetic graft?
It’s an alternative method of ligamentplasty, using a polyester-polyester material as a scaffold restraining the anterior movement of the tibia relative to femur. Return to sports is quick but, there is no long term data to this material. It is used in EU but there is no FDA approval in USA.




Synthetic graft

What about the technique in ACL reconstruction?
In general terms, we have 3 phases of the procedure. Phase 1: the graft donor surgery and its ultimate formation. Phase 2: Repair of other concomitant lesions and preparation of the osseous tunnels using arthroscoping technique. Phase 3: Passing through the graft and final fixation using the familiar hardware.


Tunnels creation


Graft fixation

Which materials are better in graft fixation?
There several ways in ACL graft fixation. Surgeons use screws, pins, bollards, staples, buttons, sheath & screw, pearls and sutures. The point is that the surgeon must be concerned about intraarticular complications in order to be able conforming to another hardware fixation.


Graft fixation materials

How much time should I stay at Hospital?
Almost 24 hours.

How strong is my ACL reconstruction?
The strength of the reconstructed ACL is dependent upon the size of the donor tendons and the method of fixation. The ultimate tensile strength of the quadruple strand technique is thought to be almost twice that of the native ligament.

Why the rehabilitation timetable program is so strict?
When tendon tissue is first harvested for a graft, as soon as the tissue is harvested it loses its blood supply. The cells within the tissue, responsible for constantly repairing the fibres of the tissue, thus die and the graft becomes little more than a biological scaffold, in which the fibres will begin to degrade and gradually rupture with time, thereby weakening the tissue.

When the graft tissue is inserted into the knee, it begins to grow a new blood supply. New cells migrate into the tissue and begin to repair and remodel the graft. Therefore, an ACL graft is nice and strong when it is first surgically implanted. However, initially the knee is weak and the reflexes impaired. As knee function improves and the patient's confidence increases, the graft begins to degenerate and actually becomes weaker. The 'danger zone' is between 3 to 9 months. As the graft develops a new blood supply within the knee after surgical reconstruction, the new cells remodel the graft and it becomes stronger. By 9 months, the graft will look and function like a new ligament and should be strong enough to cope with a full return to sports.



Graph showing how the strength of the ACL graft initially drops and then gradually returns to normal as the graft grows a new blood supply and slowly remodels. The graft is at its weakest at 3 to 6 months - just when the patient is beginning to regain confidence. It is therefore essential that return to proper sport is delayed until 9 months post-op.

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