// Injury & Rehab: Anterior Cruciate Ligament Rupture

In previous issues of Network magazine I have written about injuries to the anterior cruciate ligament (ACL) and the information that fitness professionals need to understand when dealing with clients post-ACL injury or post-ACL reconstruction. It is vital, however, that fitness professionals are kept informed of new developments in the treatment and repair of common injuries. This article focuses on one of these new developments – the Ligament Augmentation and Reconstruction System (LARS) and its use in the repair of a ruptured ACL.

Review of ACL anatomy and injuries

Injury to the anterior cruciate ligament (ACL) can occur in any physical activity that requires twisting, changes of direction or jumping – all activities commonly associated with group exercise classes and personal training sessions. The high profile of ACL injury due to its occurrence in elite athletes make this injury a subject of much interest.
The ACL runs up (superiorly) and back (posteriorly) from its attachment on the front of the tibial plateau to its femoral attachment at the back of the intercondylar notch of the femur. The major roles of this important ligament are in preventing forward movement of the tibia in relation to the femur, as well as assisting in controlling the rotation of the knee. The name ‘cruciate’ refers to the cross, or crucifix, the ACL makes with the posterior cruciate ligament (PCL) inside the knee – these ligaments, the ACL and PCL, have also been referred to as the ‘crucial’ ligaments in recognition of their importance in sporting knee performance.

A Magnetic Resonance Image (MRI) is the investigation of choice for a definitive diagnosis of an ACL rupture and will usually be arranged by the treating specialist. Once the diagnosis of ACL rupture is made, the patient must decide between a non-surgical or surgical treatment. Some factors involved in this decision include the individual’s age, degree of instability, exercise and sports demands, occupation, cost, and the person’s conviction to follow the time-consuming post-operative rehabilitation protocol. However, the use of the new Ligament Augmentation and Reconstruction System (LARS) may remove some of the post-operative issues that make the more traditional surgical repair a somewhat long and arduous process.

The LARS system

The LARS system has been in the research and development stage since the mid 1980s and has been used in some countries since the early 1990s. However, it is only just beginning to be more commonly used by Australian surgeons.
The LARS protocol involves industrial strength polyester fibres (polyethylene terephthalate) being attached to the bones to replace injured ligamentous structures like the ACL. It is believed that the polyester fibres and the arrangement of the actual knit pattern allows these artificial ligaments to bend and twist, but at the same time resist stretching that would make the new ligament ineffective in controlling joint stability. The designers also believe that the structure of the artificial ligament allows for some tissue ingrowth, whereby the ends of the injured ligament actually grow into the graft, making it even stronger and more like the original ligament.

Advantages of a LARS artificial ligament in the repair of an ACL

While this system is still in its relatively early stages – especially in Australia – there do appear to be some distinct advantages in using this method when compared to more conventional ACL reconstruction techniques such as the hamstring or patellar tendon graft, in which part of the patient’s hamstrings or patellar tendon is removed and made into an artificial ACL.

Some advantages of the LARS system may include:

  • A reduction in the amount of damage done to other body structures during the actual surgery by using the artificial ligament instead of part of the hamstring or patellar tendon.
  • Reduced recovery time as the body does not have to recover from and heal the donor graft sites in the hamstring or patellar tendon.
  • Reduced post-operative complications. Many of the most painful post-operative problems come from the donor sites, especially in the patellar tendon area, with many patients unable to kneel on their affected knee for many months after the operation.
  • Many patients report that they are able to regain full range of motion in their LARS knee within three to four weeks. This is much sooner than in more conventional reconstructions.
  • The reduced amount of tissue damage may lessen the extent of pain felt post-operatively. Having had a conventional ACL reconstruction myself (using a hamstring graft), I can confirm that the amount of pain can be significant (even for a highly pain tolerant Aussie male like myself – my wife says I screamed like a baby, but I’m sticking to my side of the story).
  • Reduced muscle wasting post-operatively, as the extent of swelling and time of immobilisation may be lessened with the LARS re-construction.

Implications for the fitness professional

It is vital that all health and fitness professionals have at least a basic understanding of some of the more common surgical procedures, as post-operative patients frequently turn to fitness facilities and personal trainers for advice on getting back into shape and increasing function after a significant injury such as an ACL rupture and subsequent reconstruction.
The early results seem to support the claim that the LARS system reduces post-operative immobilisation, pain and swelling that is a common feature of traditional ACL repair protocols. The fact that the LARS ligament is strong and solid so quickly following surgery may lead to more aggressive rehabilitation and rapid return to sport. However, as with all injury and rehabilitation issues, make sure you work closely with the client’s medical team – physiotherapist and surgeon – to ensure that the correct exercises are done at the right stage and at the correct intensity. Don’t make the mistake of thinking that, just because the ACL has been re-constructed using the LARS method, you can fast track the client back to full exercise. To do so would place you at risk of litigation and the client at risk of graft failure and another trip to the surgeon.


The LARS system looks to be a good alternative to the more conventional reconstruction procedures available to clients with an ACL injury, but the procedure is still in its infancy and all patients need to do thorough research and speak to their surgeon before deciding on which reconstruction method to use and whether the LARS system is the right option for them.

FREE resources for Network members

You can download Paul’s free e-book Injury Prevention Testing for Health Professionals and also receive five free injury prevention articles at www.FreeInjuryPreventionpdf.com
If you are interested in finding out more about building your health business you can also download Paul’s free 60-minute MP3 or CD titled How to Increase Profits from Your Health Business from www.MyHealthBusinessProfits.com


Paul Wright
Paul is the director of Get Active Physiotherapy, with clinics located inside Fitness First clubs at St Leonards (Sydney) and  Kotara (Newcastle). His 2-hour Knee Injury Prevention and Rehabilitation for Health Professionals DVD can be previewed and purchased by following the links to the DVD store at www.getactivephysio.com.au or by emailing admin@getactivephysio.com.au.

• PP 53-55