Article 3
Getting Your Angles Right
As you'd probably expect, knee pain is the most common overuse complaint in cyclists, accounting for about 25% of injuries reported. Tapping out a steady cadence of 90 RPM means your knee joint will go through 5,400 flexion and extension cycles in an hour. Anybody hoping to to complete an event like the Wicklow 200 in 8 hours can expect to flex and extend their knee nearly 44,000 times, so any pain or discomfort here, however minor to start with, is going to be physically and mentally wearing. There are many intrinsic causes of knee pain, and to further complicate matters, bio-mechanical factors at the hip and ankle can have a role in exacerbating a knee disorder. Those of you who failed Leaving Cert maths, look away now.
Your knee is basically a hinge joint between two bones; the femur (thigh) and tibia (lower leg). Your patella (kneecap) sits in a groove at this joint and offers both protection and a mechanical advantage by acting as a pulley for your quad muscles as it tracks up and down in this groove. The shaft of the femur however does not run down in a straight line. Instead it runs inwards obliquely from your pelvis, thus creating an angle at your knee known as a valgus angle, usually about 170-175 degrees. The tibia sits pretty much in a straight vertical alignment. The quad muscles attach to the femur and to your tibia via the patellar tendon. The significance of this is that the quads exert a line of pull at the knee which is at an oblique angle to the patellar tendon and tibia; in short they want to pull your kneecap sideways. This tendency is usually measured by calculating the "Q-angle" (quadriceps angle). Therefore any factor which increases the Q-angle can in theory increase stress on the knee joint. As the patella tracks over your knee joint, a weakness or imbalance in pelvic muscles, hip rotators, adductors or other stabilising structures can lead to a pull to either side of the knee cap (usually more to the outside of the knee), dysfunction in the tracking, and hence knee pain as the patella gets rubbed against the underlying bone.
At the other end, over-pronation of the foot or a fallen arch can roll your foot inwards. This then causes the tibia to adduct (come towards the midline of the body), increasing the tendancy towards a "knock-kneed" appearance, exaggerating the Q-angle and putting more stress on the knee joint.
Due to the wider pelvis, women on average have a greater Q-angle than men, and it is argued that this is one of various factors which predisposes them to more dynamic stress at the knee and therefore more knee problems as a whole. Certainly it is statistical fact that women seem to suffer proportionally higher numbers of Anterior Cruciate Ligament ruptures than men (2-6 times depending on the sport).
Whatever the reason, the long term effects of poor patellar tracking can be quite serious as wearing down of the cartilage on the underside of the patella leads to degeneration of the articular surfaces of the knee, and arthritic symptoms can result. While the role and significance of the Q-angle is somewhat controversial, the majority of research concludes it is a contributing factor to knee mechanics and stability. A good physical or sports therapist will look at the whole picture above and below the knee, and help you in addressing any bio-mechanical imbalances.
References:
Powers, Christopher M.
The Influence of Abnormal Hip Mechanics on Knee Injury: A Biomechanical Perspective
Journal of Orthopaedic & Sports Physical Therapy | volume 40 | number 2 | February 2010
Neumann, Donald A.
Kinesiology of the Musculoskeletal System
Mosby Elsevier, 2nd Ed.
--
Keith Sharkey
Associate Member of the Irish Association of Physical Therapists
email: fingal.therapy@gmail.com
Mobile: 086 0745414
References:
Powers, Christopher M.
The Influence of Abnormal Hip Mechanics on Knee Injury: A Biomechanical Perspective
Journal of Orthopaedic & Sports Physical Therapy | volume 40 | number 2 | February 2010
Neumann, Donald A.
Kinesiology of the Musculoskeletal System
Mosby Elsevier, 2nd Ed.
--
Keith Sharkey
Associate Member of the Irish Association of Physical Therapists
email: fingal.therapy@gmail.com
Mobile: 086 0745414
Article 2
Itis or Osis; what's in a name ?
I've just finished reading Laurent Fignon's autobiography. Fignon was a great guy (according to himself), and only fell out with team-mates, managers, owners, wives, surgeons, reporters, business partners, the ASO and most of the French public because they didn't recognise him for the gifted free-spirit he was and make allowances for his behaviour accordingly. He traces the start of his physical and mental decline back to 1985, when he had to undergo surgery on his achilles tendon while at the peak of his powers. Although he achieved some classics success later in his career, Fignon was never again the conquering force he was in 1984. Tendonitis of the knee or ankle is a common complaint in the cycling world, so how it could have had such a profound effect on Fignon's career ?
Firstly, a tendon is an immensely strong connective tissue comprised of parallel collagen fibres that binds muscle to bone. This high tensile strength means that a healthy tendon of 1cm2 in area is capable of bearing weights of 500 to 1000kg. They need to be this strong because of the very high loads placed on them during strenuous activity. Forces of up to 12.5 times bodyweight have been recorded in the human achilles tendon during running. Although strong, they heal slowly due to a poor blood supply and studies show that tensile strength of the new tissue can be much less than the original (1).
"Itis" generally refers to inflammation of some tissue in the body, so a tendonitis therefore means inflammation of a tendon, usually in response to some injury. So what is inflammation ? It's basically a chemical response within the body to protect and heal the injured structure. By-products of that process are typically;
Long term degeneration of a tendon can occur through age, overuse, overloading, incorrect alignment of a joint etc, anything which places increased stress on the collagen fibres and results in them breaking down. This condition is known as tendonosis because often inflammatory signs may be absent. Typically under a microscope the fibres appear disorganised and haphazard rather than running in parallel lines. If the condition isn't recognised and treated, a complete rupture can eventually occur (this is the injury often seen in footballers in the achilles).
Finally, at some sites in the body, tendons are enclosed in a sleeve or sheath which enables them to glide smoothly around other structures - again the achilles is a prime example. If tendonitis or tendonosis occurs, scar tissue can form within the sheath during the healing process and this is where real problems start. The tendon can become tethered to the sheath, restricting free movement of the joint and causing further complications such as reduced optimal muscle loading through the joint. This condition is termed tenosynovitis, and this is probably what Fignon had, given that he describes two bouts of surgery to fully excise unwanted tissue from within the achilles sheath, so we can see that he had something more serious than a mere inflammatory condition (2). Of course the elephant in the room here is the use of steroids by many riders during the 80's to boost strength and muscle development with overloading and degeneration of the tendons as a consequence, but that's a discussion for another day.
How does this all affect you ? Well, it doesn't really; even medical professionals disagree over the correct terms and many use the generic term "tendinopathy" to describe suspected conditions of the tendon. If you are experiencing pain, don't self-diagnose. Let your doctor make the diagnosis and don't worry too much about what they call it.
If you have questions on this article or another related topic, feel free to contact me.
References:
--
Keith Sharkey
Associate Member of the Irish Association of Physical Therapists
email: fingal.therapy@gmail.com
Mobile: 086 0745414
I've just finished reading Laurent Fignon's autobiography. Fignon was a great guy (according to himself), and only fell out with team-mates, managers, owners, wives, surgeons, reporters, business partners, the ASO and most of the French public because they didn't recognise him for the gifted free-spirit he was and make allowances for his behaviour accordingly. He traces the start of his physical and mental decline back to 1985, when he had to undergo surgery on his achilles tendon while at the peak of his powers. Although he achieved some classics success later in his career, Fignon was never again the conquering force he was in 1984. Tendonitis of the knee or ankle is a common complaint in the cycling world, so how it could have had such a profound effect on Fignon's career ?
Firstly, a tendon is an immensely strong connective tissue comprised of parallel collagen fibres that binds muscle to bone. This high tensile strength means that a healthy tendon of 1cm2 in area is capable of bearing weights of 500 to 1000kg. They need to be this strong because of the very high loads placed on them during strenuous activity. Forces of up to 12.5 times bodyweight have been recorded in the human achilles tendon during running. Although strong, they heal slowly due to a poor blood supply and studies show that tensile strength of the new tissue can be much less than the original (1).
"Itis" generally refers to inflammation of some tissue in the body, so a tendonitis therefore means inflammation of a tendon, usually in response to some injury. So what is inflammation ? It's basically a chemical response within the body to protect and heal the injured structure. By-products of that process are typically;
- pain - due to chemicals released
- redness - caused by increased blood flow and bleeding in the structure
- swelling (edema) - due to increased fluid build up
- heat - as a consequence of the increased blood flow in the area
- loss of function - the swelling and pain normally cause restricted movement
Long term degeneration of a tendon can occur through age, overuse, overloading, incorrect alignment of a joint etc, anything which places increased stress on the collagen fibres and results in them breaking down. This condition is known as tendonosis because often inflammatory signs may be absent. Typically under a microscope the fibres appear disorganised and haphazard rather than running in parallel lines. If the condition isn't recognised and treated, a complete rupture can eventually occur (this is the injury often seen in footballers in the achilles).
Finally, at some sites in the body, tendons are enclosed in a sleeve or sheath which enables them to glide smoothly around other structures - again the achilles is a prime example. If tendonitis or tendonosis occurs, scar tissue can form within the sheath during the healing process and this is where real problems start. The tendon can become tethered to the sheath, restricting free movement of the joint and causing further complications such as reduced optimal muscle loading through the joint. This condition is termed tenosynovitis, and this is probably what Fignon had, given that he describes two bouts of surgery to fully excise unwanted tissue from within the achilles sheath, so we can see that he had something more serious than a mere inflammatory condition (2). Of course the elephant in the room here is the use of steroids by many riders during the 80's to boost strength and muscle development with overloading and degeneration of the tendons as a consequence, but that's a discussion for another day.
How does this all affect you ? Well, it doesn't really; even medical professionals disagree over the correct terms and many use the generic term "tendinopathy" to describe suspected conditions of the tendon. If you are experiencing pain, don't self-diagnose. Let your doctor make the diagnosis and don't worry too much about what they call it.
If you have questions on this article or another related topic, feel free to contact me.
References:
1. Sharma, Pankaj & Nicola Maffuli. Tendon Injury and Tendinopathy; Healing and Repair. Journal of Bone & Joint Surgery, Vol 87 Issue 1, p187
2. Brukner, Peter, and Karim Khan. Clinical Sports Medecine. 3rd. North Ryde, New South Wales: McGraw Hill, 2009.
--
Keith Sharkey
Associate Member of the Irish Association of Physical Therapists
email: fingal.therapy@gmail.com
Mobile: 086 0745414
Flex It Like Fabian; stretching your hamstrings safely
"Cancellara...........was then asked to touch his toes; he did more than that, putting the palms of his hands flat on the ground and earning praise from the assessor. His leg length was found to be equal. He was then asked to lie on his back, straighten his leg and raise it upwards towards the vertical; he was found to have 85 degrees of angle on the right leg, with three more on the left. Pruitt was clearly impressed with this, saying that it was "very flexible for a big guy".
Fitting Saxo Bank by Shane Stokes, Feb 9 2009
As a breed, cyclists are notoriously prone to poor overall flexibility in general, and tight hamstrings in particular. All those hours spent in a relatively static low crouched position mean that the upper body, back, neck and shoulder muscles can be held in shortened positions for extended periods of time. Couple this with a traditional cycling view that all training must be "on the bike" to be of benefit, and you have a recipe for stiffness, sore muscles, and a posture like a walking question mark if you're not careful.
The hamstrings are actually comprised of three separate muscles. In order of their position from inside to outside of your leg, they are; semimembranosus, semitendinosus, and biceps femoris (1). They all originate on your "sit" bones ( the boney protuberance in your backside) and run down to attach at the back of your knee. These muscles have two jobs; they extend your hip backwards and also flex your knee. In cycling therefore, they are pretty much in a constant state of contraction, and thus particularly prone to shortening and tightening (2).
Ask yourself if you could match Cancellara in the toe-touching stakes. If you can, congratulations; you're one of the few cyclists with good hamstring flexibility. Of course Fabian is a pro, with access to the best physiological advice and support, but a few simple stretches added to your routine will help get your fingers closer to your toes, if not all the way to the floor.
Why should you bother ? Stretching won't make you as fast as Fabian, but it will help to avoid a hamstring tear next time you have to sprint for the bus, and also prevents muscular injuries and strains of the muscle tendon itself. There is also an argument that the more a muscle can stretch, the more it can contract, thus increasing its ability to generate force and delivering more power (this is known as the "length-tension relationship") (3). So take a few minutes to stretch before and after your rides, and the only thing separating you and Fabian Cancellara will be an enormous gulf in talent and class.
Stretch Guidelines
"Cancellara...........was then asked to touch his toes; he did more than that, putting the palms of his hands flat on the ground and earning praise from the assessor. His leg length was found to be equal. He was then asked to lie on his back, straighten his leg and raise it upwards towards the vertical; he was found to have 85 degrees of angle on the right leg, with three more on the left. Pruitt was clearly impressed with this, saying that it was "very flexible for a big guy".
Fitting Saxo Bank by Shane Stokes, Feb 9 2009
As a breed, cyclists are notoriously prone to poor overall flexibility in general, and tight hamstrings in particular. All those hours spent in a relatively static low crouched position mean that the upper body, back, neck and shoulder muscles can be held in shortened positions for extended periods of time. Couple this with a traditional cycling view that all training must be "on the bike" to be of benefit, and you have a recipe for stiffness, sore muscles, and a posture like a walking question mark if you're not careful.
The hamstrings are actually comprised of three separate muscles. In order of their position from inside to outside of your leg, they are; semimembranosus, semitendinosus, and biceps femoris (1). They all originate on your "sit" bones ( the boney protuberance in your backside) and run down to attach at the back of your knee. These muscles have two jobs; they extend your hip backwards and also flex your knee. In cycling therefore, they are pretty much in a constant state of contraction, and thus particularly prone to shortening and tightening (2).
Ask yourself if you could match Cancellara in the toe-touching stakes. If you can, congratulations; you're one of the few cyclists with good hamstring flexibility. Of course Fabian is a pro, with access to the best physiological advice and support, but a few simple stretches added to your routine will help get your fingers closer to your toes, if not all the way to the floor.
Why should you bother ? Stretching won't make you as fast as Fabian, but it will help to avoid a hamstring tear next time you have to sprint for the bus, and also prevents muscular injuries and strains of the muscle tendon itself. There is also an argument that the more a muscle can stretch, the more it can contract, thus increasing its ability to generate force and delivering more power (this is known as the "length-tension relationship") (3). So take a few minutes to stretch before and after your rides, and the only thing separating you and Fabian Cancellara will be an enormous gulf in talent and class.
Stretch Guidelines
- These are safe, non-aggressive techniques. Go gently into and out of the stretch position.
- Hold the leg once you feel tension. Don't bounce in the stretch position
- Keep breathing normally - don't hold your breath
- If your leg starts to shake, you're stretching too far and a stretch reflex is occurring. The muscle is fighting the stretch, so back off by either reducing the pull on the towel or bending the leg slightly at the knee.
- Hold stretches for 30 seconds to allow the tissues to respond
Upper Hamstrings
Targets the upper parts of the hams - you should feel the stretch at the back of your upper thigh
- Fold up a towel lengthways so it is approx 4 inches wide
- Lie down on your back (if you have a back problem, flex the opposing knee and hip and place your foot flat on the floor)
- Place the towel in the arch of the foot (not on the toes) of the side to be stretched
- Take hold of the towel in both hands
- Keep the knee extended (straight) or very slightly bent
- Pull the hip into flexion using the towel
Lower Hamstrings
Targets the lower fibres of the muscles - you should feel the stretch lower down near the back of your knee
- Lie down with towel around arch of your foot as above
- Flex knee and hip to 90 degrees
- Keep the hip at 90 degrees
- Pull on the towel to gradually extend the knee
1. Palastanga, Nigel, Derek Field, and Richard Soames. Anatomy and Human Movement. 5th. Philadelphia, PA: Elsevier, 2010
2. Brukner, Peter, and Karim Khan. Clinical Sports Medecine. 3rd. North Ryde, New South Wales: McGraw Hill, 2009.
3. Tortora, Gerard A, and Bryan H Derrickson. Principles of Anatomy and Physiology. 12th. Vol. 1. Danvers: John Wiley & Sons, 2009.
--
Keith Sharkey
Associate Member of the Irish Association of Physical Therapists
email: fingal.therapy@gmail.com
Mobile: 086 0745414
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