Why a "Stealth" Overtaking by a Biker is a Serious Safety Threat
Kinetic Energy Damage to a Pedestrian Threat: A biker and bike (100 kg, 223 lb) traveling at the 12 mi/hr (speed limit set by the City of Marco Island for bikes on sidewalks) if it were to impact a pedestrian walking at 1 mi/hr: ·A 100 kg bicyclist (including bike) traveling at 4.9 m/s (approx. 11 mph or 17.6 km/h) impacting a pedestrian carries a kinetic energy of approximately 1,200 Joules (KE = ½ mv^2. ·While this speed is below the typical 20+ mph threshold for high pedestrian fatality rates, it is sufficient to cause significant injury. ·Based on studies of pedestrian impacts at similar speeds (10–15 km/h), the following, damage to the pedestrian is likely: Potential Injuries
Soft Tissue Injuries: Bruising, lacerations, and contusions to the legs and torso.
Musculoskeletal Injuries: Fractures (broken bones) in the lower limbs or ribs due to direct impact from the bicycle frame.
Head/Neck Trauma: If the pedestrian falls, they may suffer injuries from hitting the ground, particularly if the collision causes a loss of balance.
Severe Injuries: While low-speed collisions often cause minor injuries, they can still cause severe or fatal injuries to vulnerable individuals (elderly, children). [1, 2, 3, 4, 5]
Factors Influencing Damage
Impact Location: A direct hit to the head or neck is more critical than an impact to the legs.
Type of Bicycle: E-bikes, because they are heavier and travel faster, can cause more severe injuries, but a 100 kg total mass for a conventional bike is similar in, mass to an e-bike, leading to similar impact energy.
Angle of Impact: A head-on collision will likely result in greater, force transfer than a glancing blow. [6, 7, 8, 9, 10]
Kinetic Energy Damage to a Pedestrian A person taking a combination of Eliquis, Plavix, and aspirin faces a significantly increased risk of serious, prolonged bleeding from even minor trauma due to triple blood-thinning therapy.
While a 2 mph bump is low-impact, it could still cause severe bruising or internal bleeding, requiring immediate medical evaluation for any impact to the head or torso.
Bleeding Risk: The combination of an anticoagulant (Eliquis) and antiplatelets (Plavix and Aspirin) is potent, significantly reducing the blood's ability to clot.
Impact Trauma: Even minor, low-speed impacts can result in subcutaneous hematomas (large, deep bruises) that might not stop bleeding quickly.
Specific Dangers: The highest risk is internal bleeding (e.g., intracranial hemorrhage from a head bump) or organ damage.
Action Required: Any trauma, even if seemingly minor, should be reported to a doctor, and emergency care should be sought if there is any sign of significant swelling, dizziness, or confusion.
For a person who must take eliquis, plavix, and asprin for cardiovascular health. How much risk is there if a biker who is overtaking me as I walk at more than twice my walking speed of 2 miles an hour.
Taking Eliquis (apixaban), Plavix (clopidogrel), and aspirin simultaneously constitutes "triple therapy" (or dual antiplatelet + anticoagulant therapy), which significantly increases your bleeding risk. For an 82-year-old on this regimen, a collision with a bike, even at moderate speeds, poses a high risk of major injury, particularly internal bleeding.
Key Risk Factors
High Bleeding Risk: Combining an anticoagulant (Eliquis) with antiplatelet drugs (Plavix, Aspirin) dramatically increases the danger of internal bleeding (especially in the brain or gastrointestinal tract) following even minor trauma.
"Silent" Bleeds: A minor fall or impact on your medication regimen might not show immediate symptoms but could cause a dangerous delayed bleed in the brain, sometimes appearing hours or days later.
High-Speed Interaction: A biker traveling at 4+ mph (twice your 2 mph speed) causes a significant impact, especially for an 82-year-old, where the risk of injury is high.
What You Should Do
Treat All Impacts Seriously: If a bike brushes you, causes you to stumble, or if you fall, you must contact your healthcare provider or go to the emergency room immediately, even if you feel fine and do not see visible bleeding.
Inform Bystanders/Paramedics: Carry a list of your medications (Eliquis, Plavix, Aspirin) on your person at all times, so emergency personnel know immediately that you are on high-risk blood thinners.
Use Protections: Consider using walking aids (cane or walker) for better balance to prevent falls.
