Diagnosis and Sideline Management of Sport-Related Concussion

The diagnosis of sport-related concussion is still based primarily on history and physical examination. Use of a standardized history and examination form is recommended. There have been many tests investigated, but none have been proven to be sensitive and specific for the diagnosis of concussion. Sideline management is based on recognition, diagnosis, and initial treatment. It is clear that symptoms of a concussion can worsen with continued play, and so, if a concussion is suspected based on observation, history, and physical examination, then the athlete should be removed from play.

Key points

•

“When in doubt, sit them out” If a concussion is suspected by anyone, then the athlete should be removed from play until evaluation by a medical professional.
•

History and physical examination are the gold standard for the diagnosis of concussion. Use of a standardized history and examination form with a graded symptom checklist is recommended.
•

There are no proven tests that can diagnose a concussion, and so tests should never be used in isolation.
•

An athlete that is on the sideline for a suspected concussion should be monitored for deterioration.
•

Any athlete exhibiting red-flag signs or symptoms should be sent to an Emergency Department via Emergency Medical Services.

Diagnosis of sport-related concussion

Sport-related concussion is a clinical diagnosis. History and physical examination are the cornerstones to identification. Several challenges exist, including a lack of a validated binary objective test, reliance on self-report, and symptoms that may overlap with other common conditions. Sometimes symptoms do not present initially and evolve over time, making serial checks of the affected athlete important. Despite this, synthesizing a combination of history, self-reported symptoms, balance testing, and vestibular, oculomotor, and other available testing can provide a foundation for appropriate diagnosis.

Key initial elements of the history include sport, age, and education. Younger athletes and children should be evaluated with a heightened sensitivity. Past concussion history, including number, how recent, and length of time to recovery, can help risk-stratify for diagnosis. Additional information regarding confounding variables, such as history of hospitalization for a head injury, history of headache disorder or migraines, attention deficit disorder/attention-deficit/hyperactivity disorder, learning disability, dyslexia, or depression/anxiety or other psychiatric disorder, can provide additional insight during evaluation.

An additional important component of history intake includes determining mechanism of action. Concussion is typically produced by a direct or indirect blow to the head or body that produces transient neurologic disruption. Initial presentation can range from an athlete whose coaches and teammates notice that they are “not acting right” to a downed competitor on the field. In the latter scenario, emergent evaluation for catastrophic injury is primary and paramount. In the more common former situation, an athlete may exhibit symptoms such as dizziness, disorientation, headaches, mood changes, balance problems and visual disturbance. The most common presenting symptom is headache, followed by dizziness. Immediate-onset dizziness correlates with greater than 6-fold risk for prolonged recovery. As mentioned, these and other concussion-related symptoms may also arise from other causes. Another challenge in diagnosis is underreporting of symptoms by an athlete in an attempt to prevent removal from competition. Despite this, taking a symptom inventory is a cornerstone of diagnostic evaluation of a concussion and has good sensitivity and internal reliability ( Box 1 ).

Box 1

Concussion-related symptoms

Headache	“Pressure in head”	Neck pain
Nausea or vomiting	Dizziness	Blurred vision
Balance problems	Sensitivity to light	Sensitivity to noise
Feeling slowed down	Feeling like “in a fog”	“Don’t feel right”
Difficulty concentrating	Difficulty remembering	Fatigue or low energy
Confusion	Drowsiness	More emotional
Irritability	Sadness	Nervous or anxious
Trouble falling asleep (if applicable)

Concussion tests

With the known challenges of concussion symptom intake (eg, underreporting), tests to provoke physical examination findings in different domains can provide added diagnostic insight ( Table 1 ). In addition to clinical examination to screen for catastrophic injury, sideline/locker room tests, such as the Modified Balance Error Scoring System (mBESS), Sports Concussion Assessment Tool 5 (SCAT5), King-Devick (KD), and vestibular/ocular motor screen (VOMS), can be helpful in this setting.

Table 1

Psychometric properties of sideline assessment tests ^a

From Harmon KG, Clugston JR, Dec K, Hainline B, Herring S, Kane SF, Kontos AP, Leddy JJ, McCrea M, Poddar SK, Putukian M, Wilson JC, Roberts WO. American Medical Society for Sports Medicine position statement on concussion in sport. Br J Sports Med. 2019 Feb;53(4):213-225; with permission.

Author	Type of Athletes	Athletes (n)	Concussed	Controls	Test and/or Criterion	Sensitivity (%)	Specificity (%)	Test-Retest Reliability	AUC
Symptoms
McCrea et al ¹⁹	College football	1631	94	56		89	100
Putukian et al ²²	College athletes	263	32	23	SCAT2	84	100
Chin et al ²³	High-school and college athletes	2018	166	164					0.88
Resch et al ¹²⁰	College athletes		40	40	Revised Head Injury Scale	98	100
Garcia et al ⁴⁰	College athletes		733		SCAT3	93	97		0.98
Broglio et al ³³	College athletes	4360						0.40 ^b
Total		3192	1065	283
Standardized assessment of concussion
Barr and McCrea	High-school and college football	1313	50	68	3-point decline	72	94	0.55 ^c
McCrea et al ¹⁹	High-school and college football	1325	63	55	3-point decline	78	95	0.48 ^d
McCrea et al ¹⁷	High-school and college football	2385	91		<10th percentile of normative	79
McCrea et al ¹⁹	College football	1631	94	56	?	80	91
Echlin et al ¹²¹	Ice hockey (age 16–21)	67	21	—	1-point decline	54
Barr et al, 2019	High-school and college football	823	59	31	?	46	87
Marinides et al ²⁰	College athletes	217	30		2-point decline	52	82
Galetta et al ²¹	Hockey/lacrosse youth/college	332	12	14	2-point decline	20	21		0.68
Putukian et al ²²	College athletes	263	32	23	<10th percentile of normative	41	91
Chin et al ²³	High-school and college athletes	2018	166	164				0.39 ^b	0.56
Broglio et al ³³	College athletes	4874						0.39 ^b
Total		15,284	618	411
BESS
McCrea et al ¹⁹	College football	1631	94	56	Modified BESS	36	95
Broglio et al ¹²²	Young adults	48			BESS			0.60 ^e
Barr et al, 2019	High-school and college football	823	59	31	Modified BESS	31	71
Putukian et al ²²	College athletes	263	32	23	Modified BESS	25	100
Chin et al ²³	High-school and college athletes	2018	166	164	Modified BESS			0.54 ^b	0.56
Broglio et al ³³	College athletes	2894			BESS			0.41 ^b
Total		4735	351	274
Oculomotor (KD)
Galetta et al ²¹	Football men’s/women’s basketball	219	10		Worsening of KD time	100
Leong et al ¹²³	Boxing				Worsening of KD >5 s	100	100	0.9 ^b
Galetta et al ²¹	Hockey/lacrosse youth/college	332	12	14	Worsening of KD time	75	93		0.92
Leong et al ²⁸	College football, men’s/women’s basketball	127	11		Worsening of KD time	89		0.95 ^b
King et al ¹²⁴	Amateur rugby				94	100		0.92 ^b
Marinides et al ²⁰	Football women’s lacrosse, soccer	217	30		Worsening of KD time	79
Seidman et al ²⁴	High-school football	343	9		Worsening of KD time	100	100
Dhawan et al ²⁹	Youth hockey	141	20		Worsening of KD >5 s	100	91
Fuller et al ¹²⁵	Elite English rugby		145		Worsening of KD time	60	39		0.51
Hecimovich et al ¹²⁶	Australian football		22	22	Worsening of KD time	98	96	0.91 ^b
	Professional football	1223	84	63	Worsening of KD	84	62	0.88 ^b
Broglio et al ³³	College athletes	755						0.74 ^b
Eddy et al ¹²⁷	Recreational college athletes	63						0.90 ^b
Total		2041	310	99
Clinical reaction time (dropped weighted stick)
Eckner ¹²⁸	College football, wrestling, women’s soccer	102						0.65 ^b
Eckner et al ⁴⁷	High-school and college athletes	28	28		90% CI	50	86
Broglio etai ³³	College athletes	261						0.32 ^b
Total