Case #1

Sandia Downhill Bomber
19 year old extreme downhill mountain biker collides with a tree, has a brief loss of consciousness. First Aid team attends to him; He recovers consciousness, his helmet is removed and his spine is immobilized. He complains of lip numbness and facial pain. 1st responder notices a loose tooth in his mouth and tries to retrieve it. The biker’s entire palate moves freely as he taps the tooth. His palate seems to be detached from the rest of his face.

Diagnosis: Le Fort Injury.
An Austrian report suggests that facial injuries, including Le Fort Fractures are common among extreme mountain bikers.
Le Fort 1: Maxilla is separated from pterygoid plate and nasal septum.
Le Fort 2 Maxilla and nose moves but not eyes
Le Fort 3 Craniofacial disjunction. Facial Skeleton separates from skull.

During transport biker becomes unconscious again, develops a widely dilated and fixed R pupil.

Diagnosis: Epidural hematoma pushes temporal lobe over tentorium, trapping CN III, and putting pressure on the midbrain. Uncal herniation. Compression of CN III is responsible for pupil.

Discussion points:
Overall mountain bikers have 40% decreased incidence of head and face injury compared to roadies. Helmet use is more frequent. Absence of cars. Downhill bikers often wear full face (motorcycle style) helmets. Despite these, head and face injuries still can occur. More on this later…

Case 2
Roadie Helmetless
Road biker doing her afternoon commute home is struck by a station wagon that failed to stop at a stop sign. She is found 25 yards from her bike, unconscious and unhelmeted. There is clear fluid oozing from the left ear and nose. A large bruise is noted behind the ears and under the eyes. A large laceration over the forehead reveals an underlying step-off of the bone. She is pulseless.

Dx: Depressed skull fracture Basilar skull fracture. Traumatic arrest. Unlikely to recover.

Road vs. Mountain bike Injury Pattern.

MTB have 40% - 60% decreased incidence of head/face/dental injuries than roadies. Decreased traffic and increased helmet use.

Rivera (1997) Seattle study. Surveyed bicycle injuries prospectively between 1992 and 1994. Study involved 7 ED’s and 3390 injured bicyclists.
Only 4% of these were mountain bikers.
73% of MTBers were between 20 and 39 years of age.
86% were male
Helmet use: 80.3% MTB vs. 49.5% on road. (Perception of risk and Difficulty changing habits) Injury cases – 29% head injured pts helmeted vs 56% of non-head injury pts helmeted.

Head and face injuries: MTB decreased risk compared to those incurred by roadies.
Severe Injuries (dislocations,concussion,fractures): 4% of MTB injured patients vs 7% of road injured. Hospitalized: MTB 6% vs 9% of road injuries.

Safer with helmets, safer off road!

In other surveys: Head injuries complicate 22-47% of injured bicyclists. Usu MVC. Head injuries account for 60% of deaths.

JAMA study: Helmets provide 4-fold protective effect against head injury. 85% effective against head injury and 88% effective against brain injury.
Helmet type: doesn’t matter. Hard shell, thin shell (most), no shell are all equally effective. All must meet ANSI, Snell requirements. Fit is probably the most important consideration when buying a helmet.
Helmets reduce risk of nose and upper face injury by 65%.
CA helmet legislation has resulted in 18% reduction in head injury for<18 yrs.



Case 3
“Slickrock Handlebar”

40 year old 1st time mountain biker rents a bike in Moab Utah. 10 minutes into the ride at slickrock, he falls off a rock ledge and lands directly on the bar-end attached to his handlebars. He develops guarding of his abdominal muscles and complains of upper abdominal pain. He does not want to be moved.

Diagnosis: Liver injury vs. Splenic injury vs. bowel injury. In this case: sub-capsular liver hematoma. These have been associated with the use of bar-ends. Many can be managed non-operatively. Of intra-abdominal injuries secondary to handlebars: spleen > liver. Spleen injuries are generally managed non-operatively, as are sub-capsular liver injuries.

Handlebar injuries.
Israeli Study of children. Handlebar mark in only 15% of children admitted for handlebar injuries. 30% had ruptures of spleen or liver. 5 of these 25 were operated on. Small bowel injuries also can occur this way when bowel is trapped between the spine and the handle bar.
Case 4
Extremity in Extremis

26 yo F bicyclist falls over the handlebars on a rocky descent. Notices brief numbness and paresthesias of R hand and cannot move R arm. L hand is becoming progressively more swollen and painful. Her companions notice a squared off R shoulder and numbness over R deltoid.

Diagnosis: R shoulder anterior dislocation. Axillary nerve injury. Consider also ulnar nerve injury. Brachial plexus injury.

Hand Exam shows snuffbox tenderness.

Most common injury involves going over handlebars. Upper extremity injury is most frequent. Abrasions, followed by contusions and sprains, then fractures and dislocations.

Attempt splinting of hand if possible and Consider reduction of shoulder. Scapular manipulation/ traction.


For hand consider splinting with a Sam Splint. If shoulder is reduced use safety pins to splint the shoulder.

Get patient to a place where XR can be performed.
Case 5
Endurance Race Wipeout
22 yo M triathlete participates in 24 hour mountain bike ride. The weather is hot, he is rehydrating with evian water and the occasional powerbar. 10 hours into the race he is getting drowsy, and beginning to have transient visual hallucinations. Is it just because it is 11:00 pm? Begins to feel weak. Then falls onto the sandstone and has a brief seizure.

Diagnosis: Hyponatremia. Fluid replacement without sufficient salt to match sweat losses. This entity has killed marathoners and triathletes every year with the advent of extreme endurance sports. Prevention with salty foods is important. Fritos might be the most important thing in your pack. Hyponatremia is one of the most common diseases to afflict visitors to the Grand Canyon


Case 6
Cactus Encounter

First time mountain biker from Oklahoma visits New Mexico and barrels down a steep foothills path, he is unhelmeted but luckily doesn’t strike his head as he tumbles over his bike into a staghorn cactus and prickly pear. He also has a deep abrasion from a sharp rock he acquainted himself with a nanosecond before kissing the cactus.


You can usually grab the end of a big thorn with needle-nose pliers. Splinter forceps (tiny sharp tweezers) are ideal.

If there are multiple small thorns in a fairly small area, try removing them with glue. Spread a generous coating of patch glue over the entire area. Wait until it dries, then peel it off. It will usually pull the thorns (and your body hairs) out as it comes away from the skin. Of course duct tape will probably work for small thorns too. If thorns remain in the skin they may provoke an inflammatory response or cause infection and may end up causing a granuloma.
Case 7
Heatstroke

Scenario:
You're sweating like a pig in the Durango sunshine, trying to figure out the Colorado trail. Dang that CamelBak is heavy on the uphills! So you dump out some water. Getting kind of dizzy. Don't stop, because the significant other will be waiting. Odd -- you're getting goosebumps despite the heat, but at least you're not sweating so much any more. Which fork do you take here? Your eyes blur and its impossible to figure out this old map. Boy, this heat is making you dizzy. Better sit down for a minute. Whoops, kind of fell down there.

Description:
Heatstroke occurs when your heat-regulation system fails. Often sweating stops and there are signs of excess adrenaline such as goosebumps. The body temperature climbs and begins to interfere with thinking. Symptoms of heat exhaustion usually precede the confusion that marks the beginning of heatstroke. Finally, consciousness is lost and brain damage (and death) can occur rapidly.

When has a biker passed the line between heat exhaustion and heat stroke? To oversimplify: if the brain isn't working perfectly (confusion, dizziness even when lying down, etc) you've crossed the line from dangerous to deadly.

Immediate care:
Immediate cooling can be lifesaving. (Often, the victim can no longer sweat, so the temperature just keeps rising. You can't just "wait it out.") Get the person out of the sun immediately. Remove extra clothing. Spread arms and legs to increase evaporative surface. Have them lie down, while keeping as much skin open to the air as possible. Wet your biking shirt, then drag it loosely over exposed skin, moving from one area to another. Keep the cloth loose and very wet, letting it pass through the air to cool between wipes. If there's a cool but shallow stream nearby, consider moving the victim so their back and legs are in the water. If you're close to a camper where ice is available, put ice in the groin, armpit, and under the back. If the victim remains confused or becomes unconscious, send someone out for help.



Case 8. “Numb Perineum”.

You are on an all day ride on the boundary trail in Taos, at mile 20, your partner begin to complain of numbness of her ring and little finger.

Dx: ulner nerve compression (ulnar tunnel syndrome or cyclists palsy). Ulnar neuropathy is much more common than median nerve palsy in cyclists.

Tx: change gloves, change handle bar position. Of note road and mtn bikers get these symptoms in roughly the same proportions. Although road bikes offer more hand positions, rides are often longer.

At mile 22, you (male) note a numbness in a sensitive area. Bilateral pudendal nerve compression. {Impotence is no more common among competitive cyclists than among other athletes}.

Change saddle, Change into more padded shorts.