What is ACL?
ACL stands for anterior cruciate ligament. It is one of the central and pivotal supporting structures of the knee joint. It prevents excessive forward movement as well as provides rotational stability during twisting forces to the knee.
Knee Ligaments Anatomy
What causes an ACL injury?
Any activity that causes sudden change in direction(cutting movements) or pivoting against locked knee (twisting forces) can put a strain on the ACL. This can happen accidentally
- While running
- Coming down-stairs
- Landing awkwardly from a jump
- Halting suddenly
- By direct blow to the thigh or knee region
The above mechanisms can happen in the setting of sports (football, kabaddi, kho-kho, cricket ,etc.), vehicular accidents or even just routine activities of daily living.
What are the symptoms after an ACL injury?
- Pain and swelling around knee
- Limp or painful weight bearing on affected leg
- Restricted bending of knee
As the initial pain and swelling reduce after taking rest for 5-7 days, the following symptoms may be apparent in the knee:
- Instability (buckling/giving way sensation), especially after walking on uneven surfaces/ stairs
- Locking (knee gets stuck momentarily while straightening)
- The knee feels loose/unsupported –hence even a normal jogging becomes difficult to initiate and sustain, although normal pace walking is fairly okay.
How can it be diagnosed?
It is initially suspected on a clinical examination by your Orthopaedic surgeon who will ask for a MRI scan to confirm the diagnosis as well as rule out associated injuries. It cannot be visualized on a simple x-ray. (although x-rays are routinely taken initially to rule out bony injuries)
MRI of normal knee
There are three grades of ACL injury:
- Grade 1:
The ligament is overstretched and less than 10% of the fibres are torn. Should heal naturally in a few weeks.
- Grade 2:
More of the fibres are torn but the ligament is still intact. May heal with a rehab programme or may require arthroscopic ACL surgery.
- Grade 3:
The ligament is completely ruptured i.e. torn in two. Usually requires arthroscopic knee surgery.
- Grade 1:
What is the treatment of ACL tear?
A complete tear of the ACL in active individuals (irrespective of the age) with symptoms of instability requires surgery in the form of arthroscopic ACL reconstruction. In this procedure, a tendon (hamstring) is harvested from the same leg, then bundled upon itself, stitched together and placed in the position of your ruptured ligament. This is a key-hole (arthroscopic) surgery which is done via small 0.5 cm incisions on your knee.
Most partial tears or ACL sprains can heal without surgery with adequate rest and muscle strengthening exercises(physiotherapy).
ACL Surgery Procedure
The procedure usually takes about 60 to 75 minutes. The patient is given spinal anaesthesia wherein a medicine is injected in his/her back so that he/she won’t feel anything in the legs for a few hours. The entire procedure is done via arthroscopy.
The first step is to harvest the graft from the back of your knee-hamstring graft harvesting. This is done via a 2-3 cm incision taken below the knee on the inner aspect using special instrument called tendon stripper. Then, your doctor will drill two holes, called “tunnels.” One tunnel will be drilled across thigh bone (above the knee) and another in the tibia (below the knee). They’ll place screws in the tunnels to hold the graft in place. It serves as a sort of bridge that a new ligament will grow on as you heal. These are bio-degradable screws- meaning they will self absorb over a period of time-around 2-3 years, requiring no removal of implant in future. It can take months for a new ACL to grow in fully-this process is called ligamentisation.
Autograft - Harvesting hamstrings
How long will the recovery take after surgery? What will be the hospital stay?
Patients are usually made to walk using crutches/walker the very next day. Though ,this procedure is frequently seen as a day care surgery, we believe in a hospital stay of at least 2 days i.e. until the patient can be up and about by himself confidently.
They can walk independently by the end of 2 weeks.
Most people can resume their office jobs from 4th week onwards. Knee can be fully bent by 5-6 weeks.
People can drive by 7-8 weeks.
Simple jogging can be done by the 4 month.
Running can be achieved by 6-7 months.
Most sports people can resume their sports anywhere from 9-12 months.
ACL Surgery Risks :
As with any type of surgery, there are risks with ACL surgery. In general, surgery may cause:
- Bleeding at the wound
- Blood clots
- Breathing issues/thrombo-embolism
- Reaction to anaesthesia
With ACL surgery in particular, the risks include:
- Knee pain
- Stiffness in your knee (Arthro-fibrosis)
- Non-healing graft
- Re-tear of new graft
- Wound complications- serous sterile discharge at bio-screw site