You do not need an ACL (Anterior Cruciate Ligament) to live a normal life or race a motorbike.

Just ask some of the top Australian motocross riders.

Todd Waters (Crankt Protein Honda Racing) ruptured his ACL this year while racing in the New Zealand motocross championship and only realised the following day. Kirk Gibbs (KTM Racing Team) ruptured his mid way through the championship last year, as did Caleb Ward (Husqvarna 8Biano Racing) – just to name a few.

It is common practice in Australia and around the world for athletes to rush off and have a ACL reconstruction without being fully informed of their options. The ACL ligament helps to stabilize the knee especially when we change directions while standing on the leg. It is vital in sports that require rapid change of direction and pivoting such as football and basketball. When it comes to riding a motorbike whether it be trail riding, racing motorcross, supercross, offroad or even fmx at the elite level you don’t need to pivot so you don’t need an ACL.

A common belief is that you will have ongoing issues or the knee will degenerate faster without surgery. This is simply not the case; research shows that long term no there is no difference in quality of life or knee damage, suggesting any long term damage is a result of the initial injury not due to repeated trauma. The main factor that affects the outcome is how strong your leg is, not the type of graft or type of surgery. If you are motivated to do the regular gym strengthening and stability exercises required to maintain muscle bulk and control, then you will have better long term outcomes. This is regardless of whether you have reconstruction surgery or not.

Another misconception I see regularly even at the national championships is riders believing that riding the bike is enough to strengthen their leg following surgery or injury. To protect an injured area you need to continue to build strength well beyond that required to just ride a bike as you need to be strong enough to handle dabbing the foot, over jumping or tucking the front. It’s not about being strong enough to ride a bike but resilient enough to handle a crash.

Short term

No Surgery
You can generally ride 7-14 days after the injury if required. Ideally a six week period would be preferred to allow the joint to settle and the regain muscle strength and control. Last year Kirk Gibbs raced just 2 weeks after rupturing is ACL at round 6 of mx nationals to keep his chances of back to back championships alive, with a 4,2 result in the mud at Conondale. Caleb Ward in 2015 raced 3 weeks after rupturing his 2nd ACL, that’s right he doesn’t have an ACL in either knee, returning to a 1-1 result at Murray Bridge Mx nationals in 2015. Riders need to understand that an ACL deficient knee will need continued gym based strengthening to maintain strength and limit instability episodes while riding. This should be part of any normal training program even if you haven’t injured your knee. If an instability episode does occur while riding, it is often reported to cause pain for less than a lap or 2.

There are different types of surgeries all with different reported benefits, however it is important to realize that graft strength is not a factor in re injury muscle strength and control are. No matter which type of surgery you get, 9-12 months of rehabilitation is required prior to racing to reduce risk of re injury back to similar levels as pre rupture. for you to limit the risk of reinjury back to somewhere close to what it was prior to injury you would need. Returning earlier places you at high risk of tearing the graft, or pulling the anchor screw out of your tibia( leg bone) into the knee joint requiring surgery to remove the screw and a bone graft to plug the hole. This has happened to both Blake “Bilko” Williams and more recently Sam Martin. Compare that to a young 15 year old Jack Simpson who took the whole season off, actually almost 14 months, to rehabilitate before returning to racing and hasn’t had any issues since.

Long term

Having the reconstruction may reduce your chance of future meniscal tears but it does not improve long term function anymore than adequate rehabilitation. Nor does it reduce the risk long term of osteoarthritis in the knee. There is occasionally people who do an adequate rehabilitation program, however after 3 months are experiencing intermittent “giving way” episodes during their daily life that I would then recommend to go get the reconstruction. This is rare in the athletic population.

I, with help from others, have also developed over the years a supportive taping specific for ACL injuries that gives you extra security under their knee braces without restricting your movement. This taping makes you feel more stable in the early stage, when riding with swelling still.

In my opinion there have unfortunately been many riders in the past who have missed opportunities and spent months out of the sport because they have had ACL reconstructions without being fully aware of their options. Bilko had multiple ACL reconstructions on each knee missing countless months on the bike and missing major international competitions. Since last rupturing the grafts and being fully informed he does not have ACLs in either knee and continues to perform at freestyle shows around the world. When he does have a crash or a instability incident, there is less damage than if he had a graft, as high compression is not developed prior to the graft or ligament rupture, the bones simply slid out and in. Don’t get me wrong this can be quite painful and not ideal for a health knee, however majority of the time swelling takes 2-7 days to settle and pain is only momentary. Prior to Kirk Gibbs fracturing his femur he reported one episode of pain while riding which was 2 weeks after the rupture, pain lasted less than half a lap and he didn’t feel it again that day.

With respect to riding a motorbike especially motocross and offroad even a minor medial collateral ligament sprain will give a rider more issues for a longer period than an ACL will.

Key points

  • You do not need an ACL to ride or race a motorbike
  • There is minimal/ no long term benefits of surgery versus an adequate rehabilitation and maintenance gym program.
  • You can get the ACL reconstruction at any point, like the end of the season if it is giving the rider symptoms.
  • It’s not about being strong enough to ride a bike but resilient enough to handle a crash.


Jon Park
Chief Sports Physiotherapist Racesafe
Director Peninsula Sports Medicine Group