A concussion is described as a rapid-onset transient neurological injury that usually resolves on its own within the first 7-10 days. A concussion may or may not result in loss of consciousness.  Concussion causes a range of bodily cognition visual emotion and sleep related interference. Signs and symptoms are broad and include headache, dizziness, disturbances in gait and balance, nausea, vomiting, photophobia, difficulty concentrating, and fatigue. People with a concussion may experience slowed mental processing, concentration, memory problems, irritability, anxiety, and depression.  Amnesia and loss of consciousness are considered the most critical signs of injury severity. These factors indicate the need for further intervention and imaging. 
Assessments that address emotional stability are beyond the scope of the physical therapist. The gold standard for diagnosing mental disorders remains a structured clinical interview with a neuropsychologist. Self-report measures can play an important role in screening patients Referral to a neuropsychologist/neuropsychiatrist in a physical therapy setting.
Research shows that concussions can cause new-onset anxiety and exacerbate existing anxiety.  Individuals with a history of mental health following an injury are at greater risk of symptoms of depression and anxiety, and their pre-existing mental health conditions worsen and develop New mental health conditions.  Neurometabolic disturbances secondary to concussion exhibit a similar pattern of brain alterations as individuals diagnosed with clinical depression on advanced neuroimaging.  Evidence of alterations in limbic-frontal circuitry after concussion Similar to functional alterations in major depressive disorder. 
Other neurochemical changes consistent between mood disorders and concussions are the presence of serotonin disturbances  and decreases in dopamine in the prefrontal cortex and brainstem.  Organic changes in the brain may explain the absence of mood and anxiety symptoms after injury Mental health before injury. Anxiety is usually triggered by vestibular events, although it may be sustained by psychosomatic factors.  For example, an athlete with a vestibular disorder may feel dizzy and anxious while practicing sprinting and then begin to avoid any Physical activity or head movement to avoid recurring dizziness. Given the overlap between symptoms of anxiety and vestibular dysfunction, clinicians should be aware of signs of anxiety when performing vestibular-oculomotor screening. If anxiety is not properly identified and Dealing with it may interfere with the effectiveness of the treatment. 
Sequencing of Evaluation
When evaluating a patient who has had a concussion event, a physical therapist should go through a spectrum of events. Based on the patient’s symptoms and possible level of dysphoria, the PT should plan to strategically schedule or delay evaluations as needed. Exam should Start with the least irritable test and work your way up to the more irritable test you can tolerate.
It is recommended that the PT classify neck pain irritability first, followed by dizziness and headache. If a patient has an irritable neck without any pathological cause, the PT should evaluate for cervical and thoracic muscle dysfunction and address any issues appropriately. If the patient has Dizziness Headache or Vertigo PT A thorough examination of cervical and thoracic spine dysfunction, oculomotor and vestibular dysfunction, and postural dysfunction should be done to determine if any of these problems are causing the symptoms.
After categorizing headache, dizziness, and pain, the PT should complete a comprehensive assessment of all domains based on clinical judgment. 
Cognition: Concussion and Clinical Reaction Time
Clinical Reaction Time
Impaired reaction time (RT) is one of the most common cognitive sequelae of concussion. It represents one of the most sensitive indicators of post-concussion cognitive changes  and has prognostic value in predicting recovery time.  Reaction time deficits occur after injury  Gradually return to baseline.  Impaired RT is often similar to the presence of other self-reported concussion symptoms, but in some athletes, RT remains impaired even after the athlete is asymptomatic.  RT is an important part of physical therapist A Concussion Assessment Toolkit to improve the sensitivity of clinical examinations to detect the effects of concussion.
Dr. James Eckner created a test that involved a systematic approach of dropping a weighted stick calibrated to reflect the reaction speed of catching it. The athlete holds his or her hand without touching the rubber disc on the bottom of the club, and the physical therapist lowers the club The athlete caught it on the way down. A physical therapist marks where his hand hits the ground, which becomes a baseline for gauging the athlete’s reaction time. In theory, if a player is later suspected of having a concussion, a physical therapist could pull out the stick and repeat The test and whether the player’s reaction time is slower can lead to the conclusion that he or she may have suffered a concussion. RT appears to be sensitive to the effects of concussion and to distinguish concussed from non-concussed athletes. The disc RT test is simple, low cost and requires minimal time. 
Figure 1 – Dr. James T. Eckner of the University of Michigan performs the disk-pin ruler test to check for a possible concussion. Credit: Ph.D. Steven Broglio
Neurocognitive Assessment Tools (NCATs)
Assessment of cognitive function is an important aspect of concussion management. However, the psychometric properties of the NCAT, especially its validity and clinical utility, have not been consistently demonstrated.  CogState/Axon/CogSport are commonly used in Australian Athletics and South African rugby. CogSport is a battery of computerized neuropsychological tests designed to measure the speed of psychomotor functions that process visual attentional vigilance and verbal and visual learning and memory.  A computerized test employs a series of eight “card games” to examine cognitive Features include simple reaction time, complex reaction time, and one-way continuous learning.
The Similar Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) is another online computerized neuropsychological testing panel consisting of three general parts:
- Part 1 – Athletes enter their demographic and descriptive information (including history of sport participation, history of alcohol and drug use, learning disabilities, attention deficit hyperactivity disorder, major neurological disorders, and history of previous concussions).
- Part 2 – Athletes self-report any of 22 concussion symptoms listed, which they rate using a 7-point Likert scale.
- Part 3 – Consisting of six neuropsychological testing modules, assessing the subject’s attentional processes, verbal recognition memory, visual working memory, visual processing speed, reaction time, number sequencing ability, and learning ability.
ImPACT has been reported to have good sensitivity-specificity and construct validity for standard neuropsychological tests of sensitivity to cognitive function associated with mTBI , but its test-retest reliability has been shown to be somewhat inconsistent. Although neurocognitive testing can Their contribution to the overall clinical picture should not be considered in isolation or over multidimensional clinical assessment methods. Future research to improve objective diagnosis of concussion and highlight individual risk factors and clinical recovery patterns NCAT’s ability to assist clinicians in making return-to-play decisions will inform best practice in concussion management programs. 
Somatosensory: Postural Control and Concussion
Concussion symptoms usually resolve within 7-10 days, but dizziness and balance impairment persist in up to 10-30% of cases, leading to serious complications (Murray et al., 2017) and are strongest predictor of prolonged recovery time.  Postural control deficits may be It is noticeable as early as 24 hours after a concussion and can last up to six months. 
During concussion events, damage to the vestibulo-ocular system as well as afferent input from the cervical spine may occur. Altered messages produced by these systems may lead to changes in the efferent inputs of the somatosensory systems, and a crescendo of maladaptive patterns may occur. Compared with healthy controls, participants with a previous concussion showed a delayed ability to selectively enhance specific relevant somatosensory information.  This can lead to further deficits in balance proprioception and body posture which, if left unaddressed, can leave athletes Vulnerable to further concussion and lower extremity musculoskeletal injury.
When the head is aligned with the torso, impact forces have been proven to be reduced by 67%.  Proper proprioception of the cervical and lumbar trunk muscles helps minimize injury by enhancing the player’s ability to preset the head in an optimal position. . These muscle groups are Mainly mediated by the vestibulospinal system, where changes in input lead to changes in the deep cervical and trunk muscles. For this reason, we need to focus on testing trunk and cervical proprioception. Understanding the impact of concussion on postural control systems is imperative Complete a physical therapy assessment.
Assess the Cervical Spine
For concussion patients, normalization of range and reduction of pain symptoms are essential. As part of your manual treatment assessment, you will assess the following:
- Whiplash associated disorder
- Cervicogenic headaches
- Cervicogenic dizziness
- Temporomandibular dysfunction
- Assess for deep neck extensor and flexor motor control dysfunction
- Assess cervical strength and endurance
Proprioception or Cervical Joint Misposition (JPE)
This test is considered the primary measure of a mismatch of afferent input to the neck leading to abnormal sensorimotor control. The test was positive in whiplash patients 
Laser mounted on head test
- The laser spot is fixed on the headband 90 -100 cm from the wall with the patient’s head in a neutral position. Align the laser with the center of the bullseye target on the wall.
- The patient closes his eyes and then tilts his head and then returns to neutral (ie as close to the center of the bull’s-eye target as possible).
- Patient now opens their eyes to see where the laser is stationary. We now measure the difference between the starting and ending positions after 3 attempts to each side.
- A difference of more than 6.5 cm indicates dysfunction (positive test) – normal is about 3-5 cm from the center of the target.
- Patients with poor proprioception may experience jerky movements or “seeking” for correct position or hyperactivity (signs of altered cervical colic reflexes) Some patients may complain of feeling dizzy or unsteady during the test.
Smooth Pursuit Neck Torsion (SPNT) Test
Part 1 of the test – eye movement control test with head and torso in neutral position. This is then compared to part 2 of the test when the torso is rotated . The head is in a neutral position over the torso. Ask the patient to follow the pen with their eyes in a figure-eight pattern.
- Rapid saccadic eye movements – looks like the eyes are trying to catch up to objects, especially at middle distances
- Reproduce the patient’s symptoms, such as dizziness or blurred vision
Part 2 of the test – This test detects changes in eye movements due to changes in afferent input from the cervical spine.  The head remains neutral while the torso is rotated 45 degrees in either direction .  Tested positive for:
- Altered eye movement control during torso rotation  or increased saccadic eye movements
- It is often seen in patients with neck pain from whiplash. 
Sensorimotor impairment – altered eye movement with trunk rotation (part 2 of test), but normal eye movement/asymptomatic with head and torso in neutral position (part 1 of test)
If the patient’s head and trunk performs poorly in neutral (part 1 of testing), and in the rotating trunk (part of the test 2), the performance remains unchanged, then it is likely to be the central nervous system disease. Instead of feeling moving disorders. 
Assessment Of Vestibulospinal System
The vestibulospinal system is responsible for postural control. Balance is often disrupted , especially in the first few days after a concussion.  Balance disturbance alone may be limited as a measure of vestibular impairment because objective clinical balance disturbance Most athletes recover within 3 to 5 days of injury. 
The Balance Error Scoring System (BESS) or the Sensory Organization Test (SOT) are commonly used to assess static vestibular impairment after concussion. However, these tests represent only the vestibulospinal aspect of the vestibular system. Dynamic aspects not covered by these tests Vestibular system or vestibular-ocular control.
Balance Error Scoring System (BESS)
The BESS is an objective measure to assess static postural stability or balance (designed for people with mild head injuries to assist in decision-making for recovery). It consists of six poses, three poses on a firm surface and the same three poses on an unstable surface (Airex foam) surface.  Athletes stood with eyes closed, with hands resting on the iliac crest, in 3 positions for 20 s: feet together, single-leg position on the person’s non-dominant leg, and tandem position (heel-to-toe standing, non-dominant foot behind).
Score one point for each error (lifting hand off iliac crest, opening eyes, tripping or falling, flexing or abducting hip more than 30 degrees, raising front foot or heel). If the patient leaves the test site for more than 5 seconds, Maximum possible score 10 The higher the score, the worse the athlete performed. The maximum total number of errors for any single condition is 10.
The BESS test has very good test-retest reliability  low to moderate sensitivity and high specificity . BESS has only been found to be useful in the first 2 days after injury
Figure 2 – Test conditions for BESS test
Sensory Organization Test (SOT)
Postural stability is the ability to control the center of gravity (COM) relative to a person’s base of support and can be affected by musculoskeletal injuries and traumatic brain injuries. NeuroCom SOT can be used to objectively quantify impairment to postural stability. This test has The ability to predict injury can be used as an acute injury assessment tool during screening and rehabilitation.
SOT uses force plates to create six sensory conditions to objectively test the patient for any abnormalities in the use of the somatosensory visual and vestibular systems to maintain postural control. Test conditions systematically eliminate useful visual and proprioceptive information To assess vestibular balance control and central nervous system adaptive responses in patients.  SOT has limitations because it is not suitable for sideline use and the equipment is expensive. It has been reported to have low sensitivity but high specificity. 
Figure 3 – Six conditions of the sensory organization test
Concussion and Benign Paroxysmal Positional Vertigo (BPPV)
Dizziness is an extremely common symptom after head trauma and is often considered post-concussion syndrome. For concussion patients who complain of dizziness, it is important to distinguish dizziness from vertigo. Dizziness is an unsteady or dizzy feeling Whereas with vertigo, the world continues to move even when a person is standing still, and usually in response to changes in head motion.
Clinicians should consider the diagnosis of benign paroxysmal positional vertigo (BPPV) when symptoms are transient in duration and associated with head movement. Specific neurological examination can diagnose this condition, important is the presence of correctable vestibular action Such a disabling and underrecognized disease. 
The Dix Hallpike Manoeuvre
The Dix-Hallpike maneuver is the gold standard for diagnosis of BPPV. The disorder is thought to be caused by calcium carbonate crystals (otoconia) that are migrated from the otolithic membrane in one of the semicircular canals of the inner ear. This absorption causes hair loss cells on canvas and maintain a continuous force until the response exhausts usually within 30 to 60 seconds. This causes a sensation of movement and nystagmus characteristic of vertigo in brief paroxysms with changes in the position of the head.
In BPPV, the posterior semicircular canal is affected 90% of the time, whereas lateral canal pathology is responsible for approximately 8% of cases. The patient lies supine with the head back and rotated towards the affected ear. This causes dizziness and spinning, usually after a 5 to 20 second delay Or upbeat nystagmus that resolves within 60 seconds. 
Figure 4 – Dix Hallpike maneuver demonstration
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