Mechanism Determines Injury Type Concussion requires brain movement inside the skull. The brain must accelerate and decelerate rapidly, producing shearing forces between brain tissue layers. This happens during: falls where the head strikes a surface and stops suddenly, collisions where the body stops but the head continues moving, whiplash where the head snaps back and forth, and rotational forces where the head twists. The force must be sufficient to overcome the cerebrospinal fluid cushion and meningeal protection (Patricios et al., 2023). A bruise requires only local tissue compression. Bumping a cabinet, doorframe, or car trunk lid compresses the scalp tissue against the skull, rupturing small blood vessels. The skull and brain are not affected. The scalp has excellent blood supply, so bruises swell quickly and look alarming. The swelling is entirely superficial. A large, painful bump on the head does not indicate brain injury if the mechanism lacked the acceleration-deceleration force. Pain intensity does not distinguish the two. Scalp bruises are often more painful than concussions in the first hours. The scalp is richly innervated and responds dramatically to compression. A concussion affects brain function, which produces symptoms that are often subtle initially and develop over hours. Severe pain at the impact site with no other symptoms favors bruise. Mild local pain with developing diffuse symptoms (headache not localized to the impact, brain fog, dizziness) favors concussion. Symptom Comparison Bruise symptoms: Pain localized to the exact spot that was hit Visible swelling or "goose egg" at the impact site Tenderness when touching the spot Pain that improves steadily over 3-7 days No symptoms when not touching or pressing the area Normal cognitive function, balance, and energy No worsening with physical or mental exertion Concussion symptoms: Headache that is diffuse (all over) or not localized to the impact Brain fog, difficulty concentrating, slowed thinking Dizziness or balance problems Fatigue disproportionate to activity Symptoms that worsen with cognitive exertion (reading, screens, conversation) Symptoms that worsen with physical exertion (walking upstairs, exercise) Nausea or light/noise sensitivity Symptoms that develop or worsen over 24-72 hours The exertion test is the most reliable differentiator. If your only symptom is pain where you were hit, and that pain does not worsen when you read, use screens, climb stairs, or concentrate, the injury is almost certainly a bruise. If headache, fogginess, or dizziness increase with cognitive or physical effort, a concussion is likely and warrants medical evaluation. Exercises for Both Scenarios JME 155 Diaphragmatic breathing serves both situations. After a bruise, the anxiety about whether the bump was "something more" activates the sympathetic nervous system, producing headache, dizziness, and brain fog that mimic concussion. Breathing calms the anxiety response and eliminates the anxiety-driven symptoms, clarifying whether remaining symptoms are injury-based. After a confirmed concussion, breathing begins autonomic recovery immediately. 10 breaths, 4-second inhale, 6-second exhale. JME 14 Chin tucks address the cervical tension that develops after any head impact, whether bruise or concussion. The startle response from an unexpected bump tenses the cervical muscles regardless of injury severity. This tension produces headache and neck stiffness that complicates the assessment. Chin tucks release this protective tension and reduce the cervical contribution to symptoms. 10 repetitions with 5-second holds, 3 times daily. JME 1 Cervical rotation helps assess cervical involvement. After a head bump, perform slow cervical rotation. If rotation reproduces or worsens headache, the cervical spine was affected by the impact (suggesting a force significant enough to involve the neck, which increases concussion probability). If rotation is comfortable and symptom-free, cervical involvement is unlikely. 10 repetitions each direction, slow and controlled. JME 150 Seated thoracic rotation maintains trunk mobility after the bracing response from impact. The whole-body startle response tightens the thoracic spine. Maintaining thoracic mobility prevents the secondary stiffness that develops from the protective response, regardless of whether the injury is a bruise or concussion. 8 repetitions per direction. Start your 3-day free trial for post-impact recovery programming. When to Seek Medical Evaluation Seek emergency evaluation for: Loss of consciousness (any duration) Seizure after the impact Worsening headache that does not respond to rest Repeated vomiting (not from anxiety) One pupil larger than the other Weakness or numbness on one side Increasing confusion or difficulty staying awake Clear fluid from nose or ears Seek medical evaluation within 24-48 hours for: Diffuse headache (not just where you were hit) Brain fog or difficulty concentrating Dizziness or balance problems Symptoms that worsen with exertion Symptoms that develop or increase over days Any concern that will not resolve without professional reassurance A bruise does not need medical evaluation unless: the swelling is extremely large, the area is soft and boggy (possible skull fracture), the bruise is behind the ear or around the eyes without direct impact (possible basilar skull fracture), or the bruise is not improving after a week. Post-Assessment Recovery JME 3 Lateral cervical flexion releases the neck tension from the startle response. Whether the bump was a bruise or concussion, the immediate startle response tightened the cervical muscles. This tension produces headache that confuses the diagnostic picture. Releasing it within the first 24-48 hours prevents the tension from becoming chronic. 8 repetitions per side. JME 42 Shoulder circles release the shoulder guarding that accompanies any head impact. The protective response elevates the shoulders toward the ears to shield the neck. This posture compresses cervical structures and restricts breathing. Shoulder circles restore normal position. 10 repetitions each direction. JME 15 Cervical extension restores posterior cervical mobility that the startle response restricted. The flexion reflex (tucking the chin) during impact shortens the posterior cervical muscles. Gentle extension restores length and improves blood flow. 8 repetitions. JME 151 Lateral side bends with breathing address the whole-body bracing response and autonomic activation from the impact. The combined trunk mobility and parasympathetic breathing provide a comprehensive post-impact reset for both physical tension and nervous system activation. 8 repetitions per side. Support your recovery with simplmobility's targeted mobility programming. The Anxiety Factor Anxiety about a head bump produces real physical symptoms. If you are worried the bump was a concussion, your sympathetic nervous system activates. This produces headache (muscle tension), dizziness (hyperventilation and autonomic activation), brain fog (cognitive resources consumed by worry), and fatigue (sustained arousal). These symptoms are real and feel identical to concussion. The diaphragmatic breathing protocol above differentiates: if symptoms improve significantly with 5 minutes of breathing, the anxiety component is dominant. Can a minor bump while walking into something cause a concussion? Walking into a stationary object (doorframe, cabinet) at normal walking speed produces 2-5g of force. Concussion requires 60-100g. Walking-speed impacts with a stationary object cannot produce concussion in a healthy adult. The pain and swelling are from scalp bruising, not brain injury. Should I wake someone up after they bump their head? If the mechanism was significant (fall, collision, sports impact), monitor for the first 4-6 hours and wake them once during the night to check responsiveness. If the mechanism was minor (walking into something, bumping a cabinet), waking is unnecessary. Sleep supports healing. How long should I monitor symptoms after a head bump? For minor bumps, 48-72 hours. If no diffuse symptoms develop and the only symptom is localized pain that is improving, the injury is a bruise. For significant mechanisms (falls, collisions), monitor for a full week, as some concussion symptoms develop gradually over 3-5 days. References Patricios, J. S., et al. (2023). Consensus statement on concussion in sport: the 6th International Conference on Concussion in Sport, Amsterdam, October 2022. British Journal of Sports Medicine, 57(11), 695-711. PubMed Giza, C. C., & Hovda, D. A. (2014). The new neurometabolic cascade of concussion. Neurosurgery, 75(Suppl 4), S24-S33. PubMed