year. (Am Fam Physician May 15;63(10): ) By far, the most injuries and deaths are in

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1 Bicycle Injuries Michael L. Whitworth, MD Injury from bicycling is inevitable if a person bicycles enough time, uses less than optimal mechanics, or is involved in a collision or fall. Injuries are classified as overuse injury, bicycle contact injury (where the body contacts the bicycle), or trauma. Trauma injuries are the most serious, and most frequently result in hospital visits/medical care system engagement. Of the traumatic injuries, only one in 10 to one in 20 seeks emergency hospital care. Overuse injuries and bicycle contact injuries are common, with resolution occurring with rest, physiotherapy, ice, and compression followed by graded increases in exercise. Bicycle injuries result in approximately deaths in the US each year, 23,000 hospital admissions, 580,000 emergency department visits, and more than 1.2 million physician visits each year. (Am Fam Physician May 15;63(10): ) By far, the most injuries and deaths are in males at a ratio of 9:1 over females. It is unclear as to why this is the case but certainly involves more male domination of aggressive riding styles and riding at night without lights on a bicycle. The types of injuries sustained depend on the type of bicycling performed: road racing, road cycling, touring, mountain biking, BMX, or stationary biking. Professional cyclists have injuries at a high rate with 94% having injuries each year. Mountain bikers have a relatively high rate of injury with 51% of recreational and 85% of competitive mountain bikers sustaining injuries each year. BMX riders often are injured performing stunts with some of these quite serious. Road riding typically is associated with all three classes of injury while stationary bikes are usually overuse injuries. Bicycle injuries may be lessened by having an appropriately sized and adjusted bicycle, wearing eyewear to prevent eye injury from flying debris or insects, using good bicycling technique to avoid overuse injury, application of spoke guards in childrens bicycles, using good biking etiquette following the laws regarding road bicycling, making yourself as visible as possible with brightly colored and contrasting designed jerseys and clothing, use of lights after dark, use of bells to signal and verbal cues to other bicyclists and pedestrians, and most of all always always wear a helmet even if it is inconvenient.

2 TRAUMA INJURIES Trauma injuries are due to sudden deceleration from falls or impacting another object. The most common trauma injury is undoubtedly the skin abrasion also known as road burn or road rash as seen below. The pic below is an elbow abrasion after a bicycle fall at 15 miles per hour on a turn that had gravel on the road. This occurs when the skin contacts the road surface resulting in superficial mechanical removal of skin. The abrasion may or may not have embedded gravel or debris that must be removed before any other treatment. "Road branding" or traumatic tatooing may occur with embedded pigmented blacktop into the wound occurring. Although these may be wounds that transcend the superficial layer, most are only dermal. Washing out the debris, use of an antiseptic, and dressing to primarily prevent further accumulation of debris and to lower pain from contact with clothing is usually done. Typically these heal without significant permanent scarring although they may look horrible. Skin lacerations result from a cutting or tearing of the skin and typically involve full thickness of the skin all the way down to the muscle. Only less commonly is the muscle involved. Sharp objects such as barbed wire that produced the laceration depicted to the left in a bicyclist, tend to create a very even edge wound while embedded rock in chip and seal cause a jagged edge wound. These wounds, if caught early enough, are closed after irrigation of the wound with sterile saline. The wound edges of a laceration may be closed with staples, stitches, or dermabond (glue). In the

3 field when dermabond or other means of closure are not available, sometimes super glue is used to close the wound edges. Typically the edges heal in around 7-10 days although structurally a laceration may not reach 50% tensile strength of normal for several months. Therefore it is important to not return too quickly to sports that will result in lateral forces against the wound edges. Lacerations frequently heal with a scar, therefore if there are facial lacerations from an accident, it is prudent to have a plastic surgeon repair the wound at the time of initial closure in the emergency department. The plastic surgeon is an expert at re-aligning the wound edges and using very fine sutures to allow healing with minimal scarring. Lacerations may become infected, possibly requiring incision and drainage later on. Frequently lacerations are covered with dressing for the comfort of the bicyclist. This injury occurs when there is skin anywhere exposed to the track of sharp objects, and may involve the fingers, knuckles, legs, thigh, buttocks, side of the back, shoulder, or face in bicycling. Contusions, (bruise) as shown on the left, are common in bicycling. These involve the breaking of blood vessels below the skin in the muscle or the skin itself with the bleeding under the skin causing swelling, discoloration, and no break in the skin. Typically these require around 3 weeks to heal and usually are not dangerous. As the blood absorbs into the body, there develop a series of colors with purple and reds initially giving way to greens and yellows as the pigment of the hemoglobin is metabolized by the body. Sprains are a tear of the ligaments holding two bones together. In road and mountain bicycling, one of the most common injuries is a shoulder sprain, that is a tear in the acromioclavicular ligament (ACL). This results in a very painful swelling over the area of connection between the clavicle (collar bone) and the acromion (part of the shoulder bone). Most of these are treated with a sling and ice, resolve and heal over around 6-8 weeks. Sometimes surgery is required to repair severe sprains, but this is unusual. Sprains of the shoulder may result in permanent deformity if the bones cannot be reduced back together during healing. Shoulder separations (ACL tear, shoulder pointer) frequently occur due to either impact directly on the shoulder or because of an outstretched hand attempting to prevent falling all the way to the road surface. Other

4 sprains involved with bicycling include the medial collateral ligament (MCL) of the knee. Fractures are not uncommon in bicyclists from falls. The hand, wrist, forearm, and shoulder are most involved whereas the femur (thigh bone) and other long bones are often involved when there is impact with a motor vehicle. The hand, wrist, forearm, and shoulder (clavicle) fractures are particularly more common when the arm is extended in an attempt to arrest the fall or lessen the impact of the fall. The forces imparted are too great, resulting in breaking of these bones. The hands may be subjected to fractures of the fingers and metacarpals especially with mountain bike contact with obstacles. Fractures are characterized by swelling, extreme tenderness both directly over the fracture site but also along almost any part of the bone. Bearing of any weight on fractured bones is extremely painful and there is limitation of mobility. The scaphoid bone is the most commonly fractured hand bone from bicycling. This is the carpal bone at the wrist at the base of the thumb. The fracture occurs due to extension of the wrist when falling, the radius bone riding over the scaphoid bone bringing all the weight of the upper body on this one small bone. The bone typically fractures across itself. It results in extreme pain over the back of the wrist, especially when the wrist is extended. Simple x-rays will determine the degree of the fracture. Sometimes a cast is used to immobilize the bones while they heal and at other times, a small screw is placed across the fracture to hold the two parts of the bone together. The radius fracture (Colles fracture) is also due to extending the wrist while falling. The large forearm bone fractures due to the forces imparted. If the

5 fracture is not displaced, casting may be an option while displaced fractures may require plating be used. Clavicle fractures may occur in the shoulder due to direct trauma to the clavicle or transmitted forces due to impact of the road surface with the wrist. Unless this is severely displaced and threatens other structures, usually there is no surgical necessity. This fracture results in a visible deformity of the collarbone that frequently is permanent, and at least temporarily while healing causes extreme pain over the fracture site. Use of a figure of eight sling is often employed immediately after the injury occurs. Skull fractures are much more common in those that refuse to wear helmets. Fragments from such fractures can cause bleeding below the skull in the brain and development of epidural or subdural hematomas, sometimes many days after the original injury. These require surgical evacuation in many cases. Using proper headgear can eradicate many of these injuries, although concussion of the brain with long term brain dysfunction may occur even without a skull fracture. Nonetheless, this largely preventable injury may result in severe life time disorders. The majority of deaths in bicyclists involved in trauma are due to head injuries. The graphs below depict the distribution of bicycle injuries presenting to the emergency departments of hospitals when using a helmet (LEFT) and without helmets (RIGHT). Ann Adv Automot Med. 2010;54:267-74

6 Head injuries increase nearly 300% without helmets, becoming the single largest injury sustained by bicyclists in this study in a closed population of 100,000 people Other Traumatic Injuries Ribs: contusion to the ribs or rib fractures may occur if there are sufficient forces involved to the ribs. Mountain biking appears to be more likely for this to occur due to handlebars impaling the ribs when the bicyclist is ejected over the front of the bike during downhill runs. This also occurs in the elderly or those taking oral steroids long term due to osteoporosis development. Chest: The handle bars on mountain bikes may impale the chest wall causing pneumothorax and other serious injury to the heart and lungs. Abdomen: Injury to the spleen, liver, or kidneys may occur since these are solid organs subject to blunt trauma forces. Although less common than other injuries, blunt trauma from automobile impacts or handlebars of mountain bikes pose risk to these organs that may require early surgical intervention. Genitourinary: The bicycle seat may cause impalement injuries to the urethra, vulva, rectum or may cause pelvic fractures Face: The face is subject to fractures and abrasions and contusions. Interestingly this is less common in mountain bikers due to their wearing protective headgear more often than road bikers. Proper fitting helmets that have chinstraps snapped snugly under the chin help reduce facial injuries. Dental injuries and severe lacerations may occur. Eyes: It is so easy to have foreign bodies such as road debris, gravel kicked up by cars or other bicycles, or insects impale the eyes. When riding at 20mph, this can cause serious injury to the eyes. Wearing hardened lens protective sunglasses or clear glasses during low light conditions may save the eyes from permanent injury. Toes: While most cyclists use appropriate footwear, sometimes children ride bicycles without shoes. Their toes can become lodged in the spokes or chain resulting in torsional injuries or even amputation injuries to the toes and feet. Always wear footwear when riding a bicycle and either tuck in laces or double/triple tie the laces to keep them out of the chain. OVERUSE INJURIES and BICYCLE CONTACT INJURY Injuries to bicyclists can occur due to excessive forces being applied to tendons, nerves, ligaments, joints, and muscles or application of forces in an unusual manner. Some of these are time limited such as the commonly seen ischeal tuberosity bursitis contact injury in new riders, whereas others are more dependent on inappropriate setup of the bicycle components or poor technique. Bicycle adjustment of components and the selection of the bicycle are the most important initially correctable features in order to lessen overuse injury and bicycle contact injury.

7 Correct Fit of Bicycle BICYCLE COMPONENT KEY MEASUREMENTS ADJUSTMENTS Frame size Clearance between frame and crotch While standing astride the frame of the bicycle: 1 to 2 inches for sports/touring bicycles, 3 to 6 inches for mountain bicycles Saddle Height 25 to 30 degrees of knee flexion of the extended leg when the pedal is at 6 o clock position or Measure the inseam (wearing cycling shoes) from floor to crotch, and multiply by or Maximum height whereby the rider is not rocking back and forth across the seat when riding. Generally lower in mountain bikes to maintain stability and maneuverability Fore/aft position With pedals at 3 and 9 o clock position, the front of the patella should be directly in line with the front of the crank arm. Tilt angle Set level (use carpenter s level), or with slightly elevated front end. Upper body Handlebar height At least 1 to 2 inches below top of the saddle (up to 4 inches for tall cyclists) Reach/extension When elbow is placed on the tip of saddle, the extended fingers should reach the

8 BICYCLE COMPONENT KEY MEASUREMENTS ADJUSTMENTS transverse part of handlebars. Width of bars At shoulder distance, wider in mountain bicycles Foot Position on pedal Foot should be in neutral position, toes not pointing up or down. Ball of foot should sit over pedal axis. The inappropriate size or setup of components of a bicycle may cause severe overuse or contact injury due to necessitating body mechanics and physics that are not optimal for pedaling or sitting. A professional bike shop fitting and adjustment can save months or years of pain and make the overall cycling experience much more enjoyable. CERVICAL AND LOW BACK STRAIN Maintaining a cervical extension position for long periods on a road bicycle may lead to significant pain in the shoulders and neck due to irritation of the facet joints and also due to excessive sustained muscle tension being used to maintain the extended cervical position for long periods of time. Cervical strain may lead to base of the neck and anterior and posterior shoulder pain that is referred from the neck. Gripping the handlebars too tightly also results in significant shoulder and neck strain, or riding with locked elbows does the same. Treatment is rest, ice, gentle exercise, and sometimes over the counter analgesic medications. Narcotics are inappropriate for this type of injury/strain. The cervical strain may be prevented by concentrating on loosening the hand grip, riding with a 15 degree angle in the elbows and avoiding winging the elbows out away from the body.

9 Occasionally it may be necessary to adjust the handlebar reach making it shorter, and tilting the seat upward degrees. Low back strain is frequently due to cervical strain, but if a person has degenerative disc disease of the lumbar spine, the forward flexion needed for road biking may be too extreme. Conversion of the bicycle components to yield a more upright posture, using a bicycle with upright geometry such as a touring or cruising bike, or use of a recumbent bicycle may prevent low back strain injury. HANDLEBAR NEUROPATHIES Excessively tight grip on the handlebars or inadequate padding may lead to handlebar neuropathies- that is compression of the deep palmar branch of the ulnar nerve or compression of the median nerve (carpal tunnel syndrome). These result in pain an numbness in the hands that may become so profound that muscle weakness ensues. The median nerve compression leads to pain in the palm of the hand and over the thenar eminence as shown. Grip strength and the ability to open jars may become impossible and the numbness may be worsened by sleeping habits, curling the hands around pillows and sheets. Use of a night time wrist splint may be useful. Prevention includes a thick taping of handlebars with a spongy pliable material, use of bicycle gloves especially gel filled, concentration on maintaining a neutral wrist position, and avoidance of a tight grip will typically stop the incidence of this neuropathy. Deep palmar ulnar nerve branch neuropathy is due to excessive pressure over the hand just beyond the wrist in line with the little finger. The ulnar nerve deep palmar branch runs through a canal called Guyons canal, and over a bone called the hamate bone of the hand. The nerve can become compressed against this bone if excessive forces are applied to the outside of the hand while riding. It results in hand pain and weakness in the ability to spread apart the fingers but no numbness. The syndrome usually improves once the compression of the nerve is stopped by resuming a more neutral hand position and not placing the body s weight on the outside of the hands. Rotating the hands slightly to redistribute weight, using the down bars, thicker handlebar

10 taping, and use of riding gloves can help reduce the symptoms. Rarely surgery is required to release the entrapped nerve. SADDLE RELATED BICYCLE CONTACT ISSUES 1. Ischeal Bursitis. The ischeal bursae are the sacs containing lubricating fluid over the bones on which we sit. The bursa can become very irritated as a person begins to bicycle with a hard narrow saddle, causing moderately profound pain when sitting on the bicycle saddle. The pain is deep in the buttocks. New riders frequently try to change out the saddle, but the problem is more in their getting used to the saddle than an excessive hardness of the saddle itself. The best solution is to use gel bead lined riding pants and ride for less length of time until the bursae become used to the saddle. Tilting the saddle backwards slightly can help relief the pressure on the ischeal bursae or lowering the saddle might help with excessive rocking. However, usually over time the problem resolves on its own. A wider saddle does provide better weight distribution but also leads to much more chafing and skin irritation, so on a road bike a narrow saddle is better. For touring bikes, a gel saddle liner with a wider seat may be more appropriate. Assuring proper saddle height and angle is of paramount importance. 2. Chaffing, Skin Irritation This can be a very painful issue leading to redness or even skin breakdown due to friction between the skin and the saddle. Riding pants that have too thin of a barrier or a malfitting saddle can lead to chafing, frequently over the inner thighs and buttocks. There are several lubricating creams commercially available to help prevent chafing should it become a problem. Chafing

11 occurs more frequently in new riders due to the skin being thinner and there being more subcutaneous fat. Also new rider technique may be less than optimal with excessive movement of the body back and forth during pedaling. Concentrating on keeping the lower body as motionless as possible on the saddle may solve the chafing problem, and continued riding will thicken the skin area over the contacts with the saddle. Lowering the saddle to reduce rocking motion can help. Irritation of the skin and soft tissues around the saddle is termed saddle soreness. Continued irritation over these areas may lead to skin breakdown and ulcerations to form in the skin making riding impossible. 3. Coccygodynia Literally, pain over the tip of the coccyx or tailbone. When sitting, most of our weight typically rests on the thighs and ischeal bursa with only a small amount focused over the coccyx. However if the bicycle saddle is tilted forward too much, the rider attempts to sit straight up for long periods to avoid other painful areas, or there is a lack of padding, the coccyx may be bruised and become painful. Chafing may also occur over the coccyx. Changing the tilt of the seat slightly backwards and using thicker lined riding pants may help with the pressure pain while chafing cream can help with the skin breakdown. 4. Pudendal and Perineal Neuropathy Compression of these nerves located just on the inside of the ischeal bursa, can lead to a deep aching pain in the perineum of the female and the back of the scrotum of the male. Bicycling worsens this pain and may lead to the onset of numbness in these areas when bicycling, then almost immediately goes away upon standing. Sitting on other hard surfaces may make the symptoms appear. Early extensive bicycling in the teens may lead to ligamentous thickening and entrapment of the nerve that is amplified by continuing long term cycling. Adjusting the seat to a wider seat may help the compression or sometimes a narrow seat is required. Surgery is only rarely used. 5. Impotence, urethritis (inflammation of the urethra), hematuria (blood in the urine), and trauma to the urethra or vulva. While these are less common, they may pose serious issues for the bicyclist. The urethra that becomes irritated results in pain on urination and in the extreme case, blood in the urine. Changing saddle position or tilt may help resolve this issue. Changing to a split saddle or cutaway saddle can help. HIP ISSUES Typically, the hip itself is rarely involved with any bicycle contact or overuse syndrome with the exception of ilopsoas tendinitis and trochanteric bursitis. The former is due to inflammation of the iliopsoas muscle, the most used thigh muscle in bicycling. The tendon crosses over a bursa (lubricating) sac that can cause both to become inflamed with overuse. The tendon attaches to

12 the top of the femur (thighbone) and the muscle is what allows us to pull the pedals upwards. Overuse of this muscle (eg in climbing hills, too fast accelerations) can result in an inflammation of these structures giving a deep ache in the front of the hip joint. It resolves with rest and tends to gradually become less irritated if a slow graded approach at strengthening this muscle occurs. Rarely, injections of steroid will be required at the head of the femur to relieve both tendinitis and the psoas bursitis, which are clinically indistinguishable from one another given the proximity of the structures involved. This condition is especially prominent in runners that may also bicycle. Strengthening of the external abdominal oblique with ab crunches and stretching of the tendon may help with the symptom resolution. Avoiding leaning back while running downhill will also stop the aggravation of the tendinitis. Trochanteric bursitis also involves the crossing of tendons from the gluteus maximus muscle and may create a clinically indistinguishable set of syndromes that may occur together or independently: trochanteric bursitis and gluteus tendinitis. Because most people and physicians are more familiar with the term of trochanteric bursitis, this is the term used to describe both syndromes. The trochanteric bursa is a series of bursa sacs (contain lubricating fluids) that serve to keep the tendons from rubbing against each other and the bone of the greater trochanter which is the side of the femur (thigh bone). The gluteus maximus is the major muscle used in bicycling pushing down on the pedals. Irritation of the trochanteric bursa or the tendon of the gluteus maximus causes pain over the side of the hip

13 when walking and also awakens people from sleeping at night. It is a deep aching pain that may be severe. Readjustment of the saddle position may help and reduction of cycling may resolve the symptoms. Steroid injections may occasionally be necessary to help with resolution but repeated frequent injections should be avoided due to complications from the steroid and due to calcium deposits that form in the tendon with repeated injections. Lowering the saddle and use of iliotibial band stretch exercises along with ice helps resolve this condition. KNEE ISSUES Patellofemoral syndrome is a painful condition sometimes seen in bicyclists when excessive forces are used on the quadriceps muscles. There may be an imbalance of muscle forces that lead to improper tracking of the knee cap in the groove in the femur and subsequently chondromalacia (degeneration of the cartilage behind the knee cap). The condition is worsened when improper pedaling technique is being used (toes pointed up) or the saddle is too far forward or too low. It may also occur when a bicyclist is pedaling hard using a full cycle pedaling technique to increase power. Pain is located directly around the patella itself and may occur at the time or the next day. Sitting in a chair is more comfortable for those so afflicted if the knee is not bent at a 90 degree angle, but is rather stretched out in extension. Correction involves elevation of the saddle, sliding the saddle back, concentration on use of a toes down technique when pedaling, ice, rest, and sometimes patellofemoral braces or taping is used. Use of a higher cadence of is recommended, staying in the lower gears, especially when climbing hills. Strengthening of the vastus medialis and hamstring muscles are also useful to help resolve this common syndrome. Occasionally, it may help for men to move the clips to the outside of the shoe whereas women should have the clips in the middle on inside of the shoe due to the differences in hip width (Q angle) between the sexes. Patellofemoral syndrome is also known as runner s knee, and the pain resolves relatively quickly after appropriate steps are taken. The quadriceps tendinitis can be a severe long term problem if overuse during bicycle training occurs. It involves weakening of the tendon at the cellular level and is not associated

14 with inflammation. Elimination of excessive quadriceps usage and avoiding bicycling for several months may be the only way to stop the condition from occurring, and avoidance of toe up positions during pedaling may help. Gradual strengthening of the tendon may be engaged. Patellar tendinitis is focal over the tendon and may resolve with rest and ice. Iliotibial band syndrome is pain on the outside of the thigh just above the knee, and is due to the iliotibial band becoming inflamed. Symptoms include pain, snapping sensation on the outer part of the knee, and a tightness around the outside of the lower thigh and knee. IT band syndrome is linked to inflexible leg musculature, leg length discrepancy, a saddle that is too high or too far back, varus alignment of the legs (bow-legged) and excessive pronation. As with the other cycling knee pain maladies, iliotibial band syndrome can be remedied by fitting the bike properly (e.g. using shims for a shorter leg, adjusting the saddle height etc.). Pes anserine bursitis is a painful inflammation over the anterior tibia (shinbone) below the knee and is due to overuse of the hamstring muscles. Hamstrings may be overused due to poor cycling technique and excessive use of the hamstring muscles. Reduction in usage and adjustment of the saddle can help. FOOT ISSUES Usually due to poorly fitting shoes or shoes too loose or too hard. Road racing shoes are rock hard on the bottom with a thick rigid plastic support. This may help most racers avoid foot injuries, but sometimes switching to a softer shoe avoids pain over the bottom of the foot. Mountain biking shoes are softer but require a different clip system.

15 References: Am Fam Physician May 15;63(10):