ACL Reconstruction Surgery-Ipsilateral
Surgery-Ipsilateral
Surgical Technique
Once the knee has pre-habilitated ACL reconstruction can be undertaken.
There is much debate in the orthopaedic literature about various aspects of ACL reconstruction including whether it is done via an open or arthroscopic (keyhole technique), which graft type is used, the rehabilitation protocols and so on.
In essence ACL reconstruction is a technical operation. The graft must be placed in exactly the right position to function normally following which the knee has to be rehabilitated appropriately. If the operation is done technically incorrect it does not matter how well or poorly the rehabilitation is undertaken the knee will not allow return to normal function.
There are a number of grafts which can be used for ACL reconstruction including Patellar tendons with bone blocks (PT), hamstrings tendons, quadriceps tendons, cadaveric allograft (taken from a cadaver and then sterilised) and synthetic grafts.
The literature demonstrates that the gold standard is the patellar tendon bone which is what I use. There are some other studies that show other grafts to be equally as good, but there are no studies to show that anything else is better than patellar tendon. There are some perceived problems with patellar tendon, but there are also similar and different problems with all the other grafts that are available including hamstring tendons, quadriceps tendon, allograft and synthetics.
The operation can be done through a mini open incision or via arthroscopic route. It does not really matter which technique is used as long as the technique allows the tunnels to be drilled in the right place and the graft placed in the correct position. I use a minimal medial open technique (show picture of incision). I feel it is the best and most reproducible method to facilitate independently drilling the tunnels in the correct place every time. If all the portal sizes of the arthroscopic techniques are added up in length the total incision size is not significantly different from a minimal open approach. There is no difference in outcome in terms of rehabilitation between an open and arthroscopic approach.
I will basically outline the steps in the operation (show pictures or diagrams):-
1. An examination under anaesthetic is done to assess the degree of laxity of all of the ligaments in the knee and record knee motion.
2. The knee is prepared and draped under sterile conditions. 20mls of local anaesthetic with adrenaline is injected into the portal sites and knee joints as pre-emptive analgesia (link). A tourniquet is elevated around the limb to allow a bloodless field for the operation.
3. An arthroscopy of the knee joint is performed to assess and deal with any other damage within the knee such as meniscus tears (link) chondral damage (link) and also to clear the ACL stump from the knee if appropriate at this stage.
4. The limb is re-prepared and draped. A small medial open incision is made to allow exposure of the knee joint and specifically of the anterior cruciate ligament. Special retractors are used within this minimal incision to allow full exposure of the ACL.
5. The ACL stump is cleared out to allow space for the new ligament to be placed. The interchondylar notch (link) containing the anterior and posterior cruciate ligaments is widened on the lateral side to allow a gap of 10 to 11mm between the posterior cruciate ligament and the lateral wall or insertion point of the anterior cruciate ligament (show diagram).
6. A free hand guide wire is placed into the tibia from the outside into the centre of the knee so that it enters the knee in the correct position of the ACL footprint (show picture). This tunnel is then over drilled to 10mm. The position of the tunnel is then posteriorised with a series of curettes to get the tunnel in exactly the correct position.
7. All the reamings from the drilling and curetting are collected and stored for use later in the operation.
8. A guide wire is placed freehand into the anatomically correct footprint of the femoral side of the ACL. This is done independently and not through the tibial tunnel. The advantage of independent placements is that it can be exactly accurate and is not limited by the tibial tunnel. If the tibial tunnel is in the wrong position this will magnify the error making the femoral tunnel also in the wrong position. By re-reaming the tibial tunnel if the wire is going through it for the femoral side it can also widen this tibial tunnel unnecessarily and so potentially compromising the fixation of the graft.
9. The femoral tunnel is a blind ending tunnel which is reamed to an appropriate depth to allow placement of the graft so that the tibial bone block is near the tibial joint surface (show picture).
10. Once again the bone reamings and drillings are collected. The individual tunnel lengths are then measured. Once the length of the tunnel is known a graft of the appropriate size can then be harvested.
11. Through the same incision a central third of the patellar tendon, taking bone blocks at the patella and tibial ends, are harvested. This graft is 10mm wide as a minimum. The bone blocks at each end are drilled with three holes through and three strong sutures are passed into each bone block.
12. The graft is measured as are the lengths of each bone block. The bone tendon interfaces are marked (show photograph).
13. A special passing drill is then used to pass the graft into the pre-drilled tunnels. The graft is advanced so that the bone block on the tibial side is just below the tibial articular surface.
14. The femoral bone block is then fixed with an interference screw (show picture).
15. The knee is then extended to ensure that there is full hyperextension of the knee with no impingement in the notch. The knee is then placed at 30° of flexion and the tibial bone block is fixed with either an interference screw or cortical button (picture). The knee is put through a full range of motion to ensure full hyperextension and full flexion is present and the fixation re-tensioned as appropriate.
16. The tourniquet is released and the bleeding is cauterised. The knee is washed out.
17. The defect in the patellar tendon is approximated and closed. The bone plug harvest sites in the tibia and patella are bone grafted with the previously collected reamings.
18. The incision into the knee capsule is then closed. Local anaesthetic is infiltrated into the wounds as well as into the knee joint. 10mls of Viscoseal (link) is also placed in the knee.
19. A full length compression stocking is placed on the knee over which a cold compression device is applied. (show picture).
20. The post operative infusion of intravenous anti-inflammatory medication is commenced for a 24 hour period. The knee is placed on a CPM machine (show picture).
21. The rehabilitation begins with predefined exercises being performed every two hours (link to rehab page).
Post Operative Period
During the post operative period the rehabilitation is commenced as soon as you wake up from the operation and the rehabilitation protocol is followed. About 99% patients go home on the day after surgery. Once the infusion of intravenous anti-inflammatories is completed a further bolus dose is given. You are also commenced on oral anti-inflammatories to start the following day which are taken regularly for 14 days along with regular Paracetamol 4 times per day, both of which are taken whether you have pain or not. The morning after surgery, you are mobilised out of bed fully weight bearing with crutches so that they do not limp, and are then allowed to go home.
The first week following the surgery, the patients do at home exactly what they did at the hospital except they will not have the CPM machine. The leg is elevated with pillows underneath the heel and not under the knee. The compression stocking and the cold compression device are on 24 hours a day. The water is exchanged in the cold compression device as necessary and the ice replenished as required. The ice usually requires replenishing after eight to twelve hours, and the water in the cuff requires changing usually after about half an hour.
The Cryocuff is removed only to do the two hourly sets of exercises as per the rehabilitation protocol. It is otherwise on all the time. You are shown how to use their Cryocuff's prior to the operation and again before you go home.
For the first week after the operation, you do not get out of bed except to go to the toilet. The aim of this is to reduce the swelling as quickly as possible and we have found that by placing this one and only restriction, then after the first week, the rest of the rehabilitation becomes fairly straightforward once the swelling has been controlled. It does mean that for the first week, you will therefore need someone at home with them to look after you, to bring you your food and drinks and so forth.
Outpatient physiotherapy commences a week after the operation, and then proceeds along the routine protocol.
I do not use braces following ACL reconstruction. I do not limit the amount of weight that can be put on the leg. The crutches are used to allow you to mobilise fully weight bearing so that the walk normally rather than trying to hobble and limp without the crutches which causes deconditioning of the leg and can slow down the rehabilitation.
Risks of the operation
All operations carry risks, but the risks following ACL reconstruction are minimal. These will be discussed with the patient prior to surgery so they are fully aware of all the risks of surgery.
ACL reconstruction is highly technical operation, but assuming it is done correctly, it has a success rate of over 90%.
There are a number of surgeons who talk about the complications following a patellar tendon ACL reconstruction. However, most of these are due to inadequate rehabilitation, which is something that I address by the aggressive rehabilitation programme that we follow, which therefore minimise the risk of problems which are often alluded to in the literature.
