This is a guide to what you can expect before and after your operation. I will go over the surgical options, the slight variations in post-operative care that you may encounter and give you a guide to rehabilitation protocols.

Specific details may vary from surgeon to surgeon but the underlying principles remain the same.


Before Surgery

How long will I wait for my operation?

This question is rather like asking 'how long is a piece of string?' the answer will be different for everybody.

It is now generally accepted that it is not ideal to operate on an acutely inflamed knee - this can make post-op recovery more difficult and in extreme cases lead to a complication called 'arthrofibrosis'.

If you and your consultant have made the decision to go ahead with surgery at the first opportunity, then it is usual at least to wait until swelling from the initial injury has settled, you have regained maximum possible range of movement and have good muscle control. The average length of time for this is approximately 4 -6 weeks from injury, however some surgeons will postpone a planned date if you have not reached the appropriate goals.

During this period you should prepare fully for your operation, not only physically but also socially and psychologically. You are about to undertake a lengthy period of recovery, the success of which is dependant on good surgery but also on a conscientious approach from you. You must be willing to put in time and effort and to follow instructions at various stages. Everyone wants you to get the best possible outcome but it is very much a co-operative team effort of which you are the main player.

You may have opted to try rehabilitation prior to making a decision regarding surgery and the length of time will vary. If rehab is going well and you have no episodes of instability then you will just continue progressing, hopefully by 6 months you will have returned to normal activities - providing you can do these with no symptoms then you will probably continue and put off surgery. Some of you may get to a certain stage of rehab and then find that you develop symptoms whenever you try to move up a level. This commonly occurs when you start to introduce activities which involve twisting, turning and cutting movements. Many people find that they can return to normal everyday activities with no problems but are unable to return to sport - it is then necessary to make a decision - adjust your sporting aspirations or have surgery!

Unfortunately we do not live in a perfect world where everyone can have immediate surgery when it becomes obvious that this is required - we are talking about waiting lists here. If you are unlucky enough to be in this situation it is important that you maintain your range of movement and strength but are careful not to subject your knee to further injury by taking part in high risk activities. Many people initially rupture their ACL, try to get back to sport too soon or in inadvisable circumstances, and subsequently damage the meniscal cartilages or the joint surface cartilage. Further damage to the joint not only causes more inflammation but can jeopardise the success of the ACL reconstruction, be patient and keep your knee in as good a condition as possible so that when your date comes up you are ready. Will I have physiotherapy prior to surgery?

Ideally yes, the physiotherapist should help prepare you fully for surgery. As we have already stated, it is vital that post injury swelling and inflammation are reduced, you have regained full movement and have adequate muscle control. Hopefully the physio will also explain the specific post-op protocol which you will be expected to follow.

If you are not referred to physio then I hope that this advice will be of benefit - follow the advice given in the early sections (stages 1,2 &3) of the conservative management and work at the recommended exercises.

At this stage please make sure you understand the principles of rehabilitation discussed earlier in this tutorial (part V), these are equally relevant in the early phases after surgery.

Will I have any other tests prior to surgery?

You may already have had X-rays and/or an MRI scan to confirm or aid the original diagnosis. If you have looked at the previous section you will also have read about the clinical tests and the KT2000 which are relevant to cruciate injury.

Some centres may want to complete objective pre-operative assessments as a baseline with which to compare post-operative results. Commonly you may be asked to complete questionnaires about your symptoms and activity level; you may have to try various functional tests such as jumping or hopping (you will only do these if considered realistic – inability to do a test is a significant result in itself!); you may be asked to complete an isokinetic muscle strength and endurance test if appropriate (depending on length of time since injury and condition of knee).


Your Operation

There are three main methods of reconstructing the ACL:

  1. Using an artificial ligament - usually made from polyester and/or carbon fibre. This technique was prevalent in the 1980's but is uncommon now.
  2. Using an 'autogenous' graft, that is, a natural graft material taken from your own body. We will look at this option in more detail, looking at the two most commonly used autogenous graft types, the 'patellar tendon graft' and the 'four strand hamstring graft'.
  3. Using an 'allograft', that is natural donor tissue. This is done more commonly in the USA but rarely in the UK.

The two common procedures include:

1 The Patellar-Tendon Graft

patellar tendon graft

(the PTG (bone-patellar tendon-bone graft, often shortened to patella tendon graft or PTG))

This technique entails removing the middle third of the patellar tendon with attached bone blocks at either end (this tendon passes from the kneecap down to the small bump on the front of the upper part of the shin bone, the bone blocks are separated from the kneecap and the shin bone). Accurate tunnels are drilled in the tibia and femur and the graft is pulled through so that the bone blocks are in the tunnels and the tendon is situated as close to the original ACL position as possible. The bone blocks provide a good strong fixation within the knee thus allowing progressive rehabilitation. If you have this type of graft you will probably have a vertical wound which is approximately 7-10cms long, this incision is superficial and does not go into the knee joint, it is where the graft has been harvested and may also be used for drilling the tunnels and inserting the graft. Any work within the knee is usually done by 'arthroscopy' (keyhole surgery). Different surgeons may use slightly varying techniques but should explain these to you if you ask.

2 The Four Strand Hamstring Graft

hamstrings graft

The hamstring muscles/tendons pass down the back of the thigh, cross the back of the knee and attach to the lower leg bones. On the inside there are two small muscles which have long tendons and one large muscle which has a short tendon. The two long tendons are used for the ACL graft, the short tendon is undisturbed so that the hamstring function not impaired too much in the early days. The two long tendons are doubled over and stitched together to make a very strong graft of four strands. Again, special tools are used to drill accurate tunnels and the graft is pulled through and fixed in place, this is also done arthroscopically.

If you have a hamstring graft you will have a small incision of approximately 4-5cms on the inside of the upper shin.

Which graft is best? The simple answer to this is neither. Both have slight advantages and disadvantages but overall the success rate of each is equivalent.

Following PTG there is a higher risk of developing symptoms associated with the kneecap and the function of the quadriceps muscle. These risks are kept to a minimum by appropriate rehabilitation ensuring good repair of the donor graft site, full flexibility and return of normal muscle strength. There has been some evidence suggesting that hamstring grafts have a tendency to stretch slightly over time, at present this is not conclusive and does not reflect in any impairment to knee function. Again, good rehabilitation will ensure full recovery of the donor site and return of normal function. The hamstring technique is also aesthetically better leaving a much smaller and less obvious scar.

Most surgeons have a graft preference which is based on the technique that they are most familiar with; it would not be sensible to ask a hamstring man to do a PTG and vice-versa (although a good surgeon will be able to perform both with good results). Occasionally the choice of graft may be governed by a secondary reason, eg if you have a job which involves kneeling or if you take part in sports where there is a high risk of developing problems associated with the quadriceps tendon or kneecap (jumping, running etc) then the hamstring graft may be preferable however, if you have a history of repetitive hamstring strains then a PTG may be the best option.


How long will I be in hospital?

This is variable. In some centres you may be discharged later on the same day, if this occurs you may be expected to return to physiotherapy the following day. More commonly you will stay one or two nights but must attain an appropriate level of mobility and safety before discharge.

The physiotherapist will get you up and walking (you may be required to use crutches initially - they are for comfort and safety only - you should not hop), once confident you will be instructed how to negotiate stairs. You will also be shown exercises and will be expected to practice these regularly throughout the day and to continue with them when you get home.


How long will I be off work?

Obviously this depends on your job but, even if you are fairly sedentary you would be wise to arrange at least two weeks off work. The biggest factor which slows recovery is excessive swelling in the joint and this is often directly proportional to how much time you spend on your feet.

The first week out of hospital should be one of almost complete rest apart from your exercise programme. You should not be on your feet unnecessarily.

During the second week you should gradually increase your activities around the house, but if you get any increase in swelling you should rest.

If you have an active job or one which involves driving you should discuss this with your surgeon, it may be 3 - 6 months before you can return to full duties.


How long before I can drive?

This really is dependant on whether it is your right or left leg affected and whether you drive an automatic. For the UK, where the driver sits on the right of the car:

Left leg: You must wait at least 48 hours after an anaesthetic, even if you drive an automatic. After this time you must be able to easily get in and out of the car and be able to control the clutch - we're probably looking at 1-2 weeks.

Right leg: There is evidence to show that it is 3-4 weeks before your normal reflex reaction time returns, therefore driving prior to this is inadvisable. It is important you have good reaction speed in case of an emergency stop.