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ANTERIOR CRUCIATE LIGAMENT TEARS

The anterior cruciate ligament (ACL) is commonly injured, particularly in sports involving acceleration, deceleration and change of direction. It can be injured during relatively benign events as well.
This anterior cruciate ligament can be partially or completely torn.

Partial tears are rare and conservative treatment can be considered. This involves protecting the cruciate ligament for a period of 3 to 6 months. Together with this, significant physiotherapy and biokinetic rehab is necessary.

In the majority of cases, the anterior cruciate ligament is completely ruptured.

The completely ruptured anterior cruciate ligament can be treated conservatively which involves physiotherapy, biokinetics and rehab. This can sometimes return the patient to full sporting activities with a non-symptomatic knee.

Multiple scientific studies have established however, that without an anterior cruciate ligament there is increased rotational and anterior-to-posterior instability. This may not produce episodes of instability. Despite a lack of symptoms, ACL deficient knees show increased damage to the menisci and early onset degenerative osteoarthritis.

The primary goal of ACL reconstruction is to stabilize the knee and delay the onset of osteoarthritis. Thus patients of any age who maintain a relatively active lifestyle regardless of sporting choice may benefit from anterior cruciate ligament reconstruction.

rvb-anterior-cruciate-ligament-tears-01 2 rvb-anterior-cruciate-ligament-tears-02 2

The left hand photograph shows the ruptured and incomplete Anterior Cruciate Ligament and the right hand view demonstrates the reconstructed ligament.

The decision whether or not to have the anterior cruciate ligament reconstructed is a personal choice based on the information available, and discussion with the surgeon.

 

Surgery
The State of the Art surgical technique is to create an “ANATOMIC ACL RECONSTRUCTION”. To achieve this position of the reconstructed ligament must be in the anatomic “footprint” of the ruptured ACL. I do anterior cruciate ligament reconstruction as an arthroscopic or keyhole surgery. The ligament is reconstructed using a substitute graft.

The graft is pulled through the tibia (lower bone) and then the femur (upper bone).
It is then fixed to the femur with an endobutton and to the tibia with an interference screw.

Graft Choices

  1. Hamstring Autograft
    The ‘gold standard’ worldwide is the patient’s own hamstring tendon as graft. Each leg has five hamstrings. Two of these are harvested through a 25mm incision. These tendons produce the least complications with results better than or equal to all other graft choices.
  2. Patella Tendon Autograft
    Another option is patellar tendon harvested from the patient. The middle third of the patella tendon below the knee cap is harvested together with a small block of bone at each end. This also produces excellent results, but has a higher incidence of anterior knee pain and a slightly higher incidence of complications.
  3.  Quadriceps Tendon
    Quadriceps tendon has similar results to patellar tendon graft
  4. Allograft.
    This is donor graft from a deceased organ donor. Either a tibialis tendon or an Achilles tendon. The advantage is decreased surgery as no graft is harvested during the procedure from the patient. This then allows a quicker recovery initially. The disadvantage is in South Africa all meniscal allograft is irradiated to decrease infectious risk. This unfortunately decreases the mechanical properties of the graft. The re-rupture rate is accordingly slightly higher.

Rehab

  1. Partial weight bearing on crutches for the first 10 days or longer depending on the associated injury.
  2. Postoperatively the patient is protected in a hinged knee brace for 6 weeks.
  3. Physiotherapy started to decrease the swelling and inflammation, regain motion and recover strength.
  4.  The final phase of recovery is guided by a Biokineticist, to regain balance, power and control.

It is typically after 6 to 9 months that a patient is able to return to sport but it can be longer before they regain their top speed and acceleration.

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