Lately we have heard of too many injuries, including a lot of knees. Jokingly we call that “Kneesles” or “Kneemonia” but it’s usually damaged ligaments or other supporting soft tissues and it often puts riders out of action for up to a year. Some riders, like Darryl Curtis, suffer from ongoing knee issues for years afterwards. So we thought we should highlight the importance of wearing good knee braces.

Knee guards versus knee braces

Knee guards are a whole lot cheaper (R250 to R1200) because they are designed to provide some protection for the knee area from impacts with the ground, branches, rocks etc. They are not designed to stop the knee twisting or to provide support for the knee against the strains of having the lower leg and upper leg trying to move in different directions. Knee braces are a lot more expensive (from about R6 000 for “off-the-shelf” models to R20 000 for custom made CTi’s), but they are designed to support the knee in these situations.

The only time I have injured a knee was before I wised up and invested in knee braces. Since then I have injured many other body parts but thankfully not my knees. In a study data from 2115 off-road motorcycle riders was obtained using an internet-based survey over a 1-year period. Participants were grouped by use or nonuse of knee braces, and an incidence rate ratio was used for injury rate comparison.

Participants recorded 39 611 riding hours over the study period. A total of 57 riders (2.7%) sustained at least 1 knee injury, for a total of 89 injuries. The most common injuries involved the anterior cruciate ligament, menisci, and medial collateral ligament. There was a significantly higher rate of overall injuries in the non-braced group versus the braced group (3.675 vs 1.587 per 1000 rider hours). Significantly higher incidence rates of anterior cruciate ligament rupture (1.518 vs 0.701 per 1000 rider hours) and medial collateral ligament injury (0.799 vs 0.111 per 1000 rider hours) were found among non-braced riders compared with braced riders.

The most common knee injuries in off-road motorcycling involve the anterior cruciate ligament, menisci, and medial collateral ligament. The study concluded that the use of prophylactic knee bracing appears to have a beneficial effect in preventing medial collateral ligament and anterior cruciate ligament injuries as well as overall knee injury occurrence.

knee-guards02I asked Dr. Richard Kyte, the Orthopaedic Surgeon who performed miracles to save my feet and ankles after the helicopter accident I had 5 years ago, to give us his thoughts on knee braces and our sport. It is interesting that he points out the importance of how well the brace “conforms” (fits the leg/ knee) – obviously then there is a lot of value in custom-made braces.

Dr. Kyte writes –

“The knee joint is composed of the femur, tibia & patella in the front and protected and supported by ligaments (static stabilisers) & muscles and tendons (dynamic stabilisers). These two groups of stabilisers complement one another and one may assist the function of another when either is malfunctioning. There are two cruciate ligaments (the “anterior cruciate ligament” (ACL) in the front and the “posterior cruciate ligament”(PCL) at the back, which cross over inside the middle of the knee, resisting shear forces antero-posteriorly (front-to-back). There are two collateral ligaments on either side of the knee, which stop the knee bending inwards or outwards (so-called varus or valgus forces / stresses & strains).

The quadriceps muscles & tendon stabilises the knee in front, stopping it from slipping backwards, similar to the PCL, and the hamstring muscles & tendons stabilise the knee at the back, stopping it from slipping forwards (similar to the ACL).

Ligaments (which connect bones to bones) are composed of almost the same stuff as tendons (which connect muscles to bones) i.e. collagen (the same stuff scars are made from) but have more elastic fibres in them (“elastin”), which provides their greater elasticity. This means they can deform/ stretch more before snapping (as opposed to tendons).

Knee ligaments are damaged by any twisting load or direct antero-posterior (i.e. front-to-back) force against either the femoral side or the tibial side of the knee resulting in shear forces, thereby stretching and snapping the ligaments.

Motorcyclists may be prone to rotational or direct shear forces when falling – or, perhaps, even an unsteady cornering manoeuvre! Another example: planting a foot against the road (e.g. when trying to stop the bike) would cause the femur/ thigh to continue forwards and the tibia be delayed by the friction against the ground producing the same shear forces as if something had been forced against the tibia or femur causing one to want to move away from the other, stretching and snapping the anterior cruciate ligament and maybe tearing the hamstring muscles (both want to stop the femur slipping forwards on the tibia).

The more conforming a knee brace, the better it would be in assisting the static and dynamic stabilisers of the knee (the ligaments, muscles and tendons). This prevents – or greatly minimises – the tendons and also the ligaments from reaching their tensile breaking point i.e. the knee is cocooned in a shell!

I would recommend such a brace, it will, undoubtedly, help prevent injuries.”

knee-guards04 knee-guards03

Personally I use Ossur CTi custom knee braces and feel they are well worth the additional cost because they are made for your individual legs. To order them you have to go to a qualified Orthotist (there are several appointed by Ossur South Africa in most parts of SA) who do an intensive measuring up of your legs. The data is sent to the factory where the braces are made from carbon fiber specifically for you, then air-freighted back to the Orthotist who sets them up to fit perfectly and teaches you how to use them effectively. Yes they are expensive but apparently some medical aids will actually pay for them if your doctor motivates it.
If the cost of CTi’s is out of the question, EVS make a range of very good braces. I have been very impressed with the EVS “Axis Pro”.
I also have a lot of time for the Asterisk knee brace which I used for 7 years without injury before upgrading to CTi.
Remember that if you could ride perfectly – never putting a leg out, never dabbing hard, never impacting with anything, never paddling awkwardly over rocks etc – you wouldn’t need knee braces (or boots, helmet, neck brace etc). So do all you can to ride better, keeping your legs out of harms way, and to ride within your abilities. Also see the Basefit article in this issue to find out how you can strengthen tendons.