The incidence and burden of injuries in elite English youth female soccer players

Figures & data

Table 1. Number (%) and incidence of all injuries, and the severity and burden for injury onset, mechanism and severity category of time-loss injuries.

	Total				Match				Training
	Exposure = 52,834 hours				Exposure = 6,373 hours				Exposure = 46,461 hours
	Number (% of total)	Incidence (95% CIs)	Median severity (IRQ)	Burden (95% CIs)	Number (% of total)	Incidence (95% CIs)	Median severity (IRQ)	Burden (95% CIs)	Number (% of total)	Incidence (95% CIs)	Median severity (IRQ)	Burden (95% CIs)
All injuries	142 (100)	2.7 (2.3–3.2)	-	-	73 (100)	11.5 (9.1–14.4)	-	-	69 (100)	1.5 (1.2–1.9)	-	-
Non-time loss	31 (21.8)	0.6 (0.4–0.8)	-	-	14 (19.2)	2.2 (1.3–3.7)	-	-	17 (24.6)	0.4 (0.2–0.6)	-	-
Time-loss	111 (78.2)	2.1 (1.7–2.5)	10 (4–22)	37 (31–44)	59 (80.8)	9.3 (7.2–11.9)	10 (4–24)	183 (142–237)	52 (75.4)	1.1 (0.9–1.5)	9 (4–20)	17 (13–22)
Injury onset
Acute	106 (74.6)	2.0 (1.7–2.4)	9 (4–21)	35 (29–43)	56 (76.6)	8.8 (6.9–1.4)	28 (14–32)	173 (133–225)	50 (72.5)	1.1 (0.8–1.4)	9 (4–20)	16 (12–21)
Gradual	5 (3.5)	0.1 (0.0–0.2)	20 (3–28)	2 (1–4)	3 (4.1)	0.5 (0.2–1.5)	10 (4–22)	10 (3–31)	2 (2.9)	0.0 (0.0–0.2)	12 (7–16)	0 (0–2)
Injury mechanism
Contact	53 (37.3)	1.0 (0.8–1.3)	8 (4–19)	13 (10–27)	37 (50.7)	5.8 (4.2–8.0)	10 (4–22)	82 (59–113)	16 (23.2)	0.3 (0.2–0.6)	7 (4–19)	4 (2–6)
Non-contact	58 (40.9)	1.1 (0.8–1.4)	10 (5–26)	24 (18–31)	22 (30.1)	3.5 (2.3–5.2)	10 (6–33)	102 (67–154)	36 (52.2)	0.8 (0.6–1.1)	11 (5–22)	13 (10–18)
Injury severity time bins
1–3 days	17 (12)	0.3 (0.2–0.5)	1 (1–3)	1 (0–1)	10 (13.7)	1.6 (0.8–2.9)	2 (1–3)	3 (2–5)	7 (10.1)	0.2 (0.1–0.3)	1 (1–2)	0 (0–0)
4–7 days	26 (18.3)	0.5 (0.3–0.7)	4 (4–6)	2 (2–4)	10 (13.7)	1.6 (0.8–2.9)	4 (4–6)	8 (4–14)	16 (23.2)	0.3 (0.2–0.6)	4 (4–6)	2 (1–3)
8–28 days	46 (32.4)	0.9 (0.7–1.2)	14 (9–20)	13 (10–17)	25 (34.2)	3.9 (2.7–5.8)	13 (9–17)	55 (37–81)	21 (30.4)	0.5 (0.3–0.7)	19 (11–20)	7 (5–11)
> 28 days	22 (15.5)	0.4 (0.3–0.6)	42 (34–59)	21 (14–32)	14 (19.2)	2.2 (1.3–3.7)	42 (35–66)	118 (69–203)	8 (11.6)	0.2 (0.1–0.3)	38 (33–52)	7 (4–15)

Injury incidence, the number of injuries per 1000 exposure hours (95% CI). Severity, days lost to injury (IQR). Injury burden, the number of days lost per 1000 exposure hours (95% CI). – indicates variable cannot be calculated for this category. N.B. One ACL injury sustained in match-play resulting in 419 days absence was removed when calculating due to its disproportionate influence on severity and burden estimates.

Table 2. Overall, match and training injury location number, incidence, median severity and burden for time-loss injuries.

	Total				Match				Training
Region Location site	Number (% of total)	Incidence (95% CIs)	Median severity (IRQ)	Burden (95% CIs)	Number (% of total)	Incidence (95% CIs)	Median severity (IRQ)	Burden (95% CIs)	Number (% of total)	Incidence (95% CIs)	Median severity (IRQ)	Burden (95% CIs)
Head & neck	6 (5.4)	0.1 (0.1–0.3)	4 (2–6)	1 (0–2)	4 (6.8)	0.6 (0.2–1.7)	4 (2–10)	5 (2–14)	2 (3.8)	0.0 (0.0–0.2)	4 (4–4)	0 (0–1)
Head & face	5 (4.5)	0.1 (0.0–0.2)	4 (2–4)	1 (0–2)	3 (5.1)	0.5 (0.2–1.5)	2 (2–13)	4 (1–14)	2 (3.8)	0.0 (0.0–0.2)	4 (4–4)	0 (0–1)
Neck & cervical spine	1 (0.9)	0.0 (0.0–0.1)	6 (6–6)	0 (0–1)	1 (1.7)	0.2 (0.0–1.1)	6 (6–6)	1 (0–7)	-	-	-	-
Upper limb	11 (10.0)	0.2 (0.1–0.4)	17 (11–36)	5 (3–8)	8 (13.6)	1.3 (0.6–2.5)	25 (12–39)	31 (15–62)	3 (5.8)	0.1 (0.0–0.2)	15 (8–22)	1 (0–3)
Shoulder/clavicle	2 (1.8)	0.0 (0.0–0.1)	34 (31–36)	1 (0–5)	1 (1.7)	0.2 (0.0–1.1)	38 (38–38)	6 (1–42)	1 (1.9)	0.0 (0.0–0.2)	29 (29–29)	1 (0–4)
Wrist	4 (3.6)	0.1 (0.0–0.2)	17 (1–36)	2 (1–4)	3 (5.1)	0.5 (0.2–1.5)	33 (17–39)	12 (4–38)	1 (1.9)	0.0 (0.0–0.2)	1 (1–1)	0 (0–0)
Hand/finger/thumb	5 (4.5)	0.1 (0.0–0.2)	15 (14–17)	2 (1–4)	4 (6.9)	0.6 (0.2–1.7)	16 (12–23)	13 (5–33)	1 (1.9)	0.0 (0.0–0.2)	15 (15–15)	0 (0–2)
Trunk	6 (5.5)	0.1 (0.1–0.3)	8 (8–10)	4 (2–8)	5 (8.5)	0.8 (0.3–1.9)	8 (8–10)	29 (12–70)	1 (1.9)	0.0 (0.0–0.2)	8 (8–8)	0 (0–1)
Sternum/ribs/upper back	1 (0.9)	0.0 (0.0–0.1)	8 (8–8)	8 (1–57)	1 (1.7)	0.2 (0.0–1.1)	8 (8–8)	1 (0–9)	-	-	-	-
Lower back/sacrum	5 (4.5)	0.1 (0.0–0.2)	8 (8–10)	4 (1–8)	4 (6.8)	0.6 (0.2–1.7)	9 (7–46)	28 (10–74)	1 (1.9)	0.0 (0.0–0.2)	9 (9–9)	0 (0–1)
Lower limb	87 (79.1)	1.6 (1.3–2.0)	10 (4–21)	28 (23–34)	42 (71.2)	6.6 (4.9–8.9)	10 (4–21)	118 (87–160)	46 (88.5)	1.0 (0.7–1.3)	10 (4–20)	15 (12–21)
Hip/groin	15 (13.5)	0.3 (0.2–0.5)	11 (6–20)	5 (3–9)	7 (11.9)	1.1 (0.5–2.3)	10 (6–17)	19 (9–41)	8 (15.4)	0.2 (0.1–0.3)	12 (6–26)	4 (2–7)
Anterior thigh	9 (8.1)	0.2 (0.1–0.3)	4 (4–12)	1 (1–2)	2 (3.4)	0.3 (0.1–1.3)	6 (5–8)	2 (1–8)	7 (13.5)	0.2 (0.1–0.3)	4 (2–12)	1 (1–2)
Posterior thigh	14 (12.6)	0.3 (0.2–0.4)	19 (6–32)	6 (3–10)	4 (6.8)	0.6 (0.2–1.7)	23 (14–30)	13 (5–35)	10 (19.2)	0.2 (0.1–0.4)	16 (6–32)	5 (2–9)
Knee	18 (16.2)	0.3 (0.2–0.5)	10 (4–20)	7 (4–11)	11 (18.6)	1.7 (1.0–3.1)	12 (4–25)	40 (22–75)	7 (13.5)	0.2 (0.1–0.3)	6 (5–20)	2 (1–5)
Lower leg/Achilles tendon	5 (4.5)	0.1 (0.0–0.2)	8 (6–9)	1 (0–3)	4 (6.8)	0.6 (0.2–1.7)	7 (5–15)	8 (3–21)	1 (1.9)	0.0 (0.0–0.2)	9 (9–9)	0 (0–1)
Ankle	20 (18.0)	0.4 (0.2–0.6)	10 (6–21)	6 (4–9)	10 (16.9)	1.6 (0.8–2.9)	10 (6–19)	24 (13–45)	10 (19.2)	0.2 (0.1–0.4)	14 (6–22)	3 (2–6)
Foot/toe	7 (6.3)	0.1 (0.1–0.3)	8 (5–20)	2 (1–4)	4 (6.8)	0.6 (0.2–1.7)	14 (5–26)	11 (4–29)	3 (5.8)	0.1 (0.0–0.2)	8 (6–14)	1 (0–2)

Injury incidence, the number of injuries per 1000 exposure hours (95% CI). Severity, days lost to injury (IQR). Injury burden, the number of days lost per 1000 exposure hours (95% CI). – indicates that no time-loss injuries occurred within this category. N.B. One ACL injury sustained in match-play resulting in 419 days absence was removed when calculating due to its disproportionate influence on severity and burden estimates.

Table 3. Overall, match and training injury type number, incidence, median severity and burden for time-loss injuries.

Injury type	Number (% of total)	Incidence (95% CIs)	Median severity (IRQ)	Burden (95% CIs)	Number (% of total)	Incidence (95% CIs)	Median severity (IRQ)	Burden (95% CIs)	Number (% of total)	Incidence (95% CIs)	Median severity (IRQ)	Burden (95% CIs)
Muscle strain	37 (33.3)	0.7 (0.5–1.0)	10 (5–20)	11 (8–15)	13 (22.0)	2.0 (1.2–3.5)	10 (4–18)	35 (21–61)	23 (46.2)	0.5 (0.3–0.8)	10 (5–20)	7 (5–11)
Spain/ligament injury	30 (27.0)	0.6 (0.4–0.8)	10 (6–22)	11 (8–16)	19 (32.2)	3.0 (1.9–4.7)	10 (6–19)	60 (38–96)	11 (21.2)	0.2 (0.1–0.4)	20 (6–26)	4 (2–8)
Haematoma/contusion/bruise	19 (17.1)	0.4 (0.2–0.6)	6 (4–10)	3 (2–4)	9 (15.3)	1.4 (0.7–2.7)	6 (3–8)	8 (4–16)	10 (19.2)	0.2 (0.1–0.4)	6 (4–14)	2 (1–3)
Other injuries	10 (9.0)	0.2 (0.1–0.4)	5 (2–24)	3 (2–6)	4 (6.8)	0.6 (0.2–1.7)	5 (2–8)	8 (4–17)	4 (7.7)	0.1 (0.0–0.2)	26 (3–54)	3 (1–7)
Fracture	6 (5.4)	0.1 (0.1–0.3)	36 (24–40)	4 (2–8)	6 (10.2)	0.9 (0.4–2.1)	36 (24–40)	31 (14–68)	-	-	-	-
Other bone injury	5 (4.5)	0.1 (0.0–0.2)	20 (8–42)	4 (2–10)	4 (6.8)	0.6 (0.2–1.7)	25 (6–70)	32 (12–87)	1 (1.9)	0.0 (0.0–0.2)	25 (6–70)	0 (0–3)
Tendinosis	2 (1.8)	0.0 (0.0–0.2)	12 (7–16)	0 (0–2)	-	-	-	-	2 (3.8)	0.0 (0.0–0.2)	20 (20–20)	1 (0–2)
Apophysitis	1 (0.9)	0.0 (0.0–0.1)	28 (28–28)	1 (0–4)	1 (1.7)	0.2 (0.0–1.1)	28 (28–28)	4 (1–31)	-	-	-	-
Concussion	1 (0.9)	0.0 (0.0–0.1)	24 (24–24)	0 (0–3)	1 (1.7)	0.2 (0.0–1.1)	24 (24–24)	4 (1–27)	-	-	-	-

Injury incidence, the number of injuries per 1000 exposure hours (95% CI). Severity, days lost to injury (IQR). Injury burden, the number of days lost per 1000 exposure hours (95% CI). – indicates that no time-loss injuries occurred within this category. N.B. One ACL injury sustained in match-play resulting in 419 days absence was removed when calculating due to its disproportionate influence on severity and burden estimates. 

Table 4. Total, match and training injury number (%), incidence, severity and burden for all age groups for time-loss injuries.

	Total				Match				Training
	U10	U12	U14	U16	U10	U12	U14	U16	U10	U12	U14	U16
Exposure (hours)	7347	12,813	16,076	16,598	706	1563	1919	2185	6641	11,250	14,158	14,413
Number (% of total)	3 (2.7)	15 (13.5)	40 (36)	53 (47.7)	1 (1.7)	7 (11.9)	21 (35.6)	30 (50.8)	2 (3.8)	6 (11.5)	19 (36.5)	23 (44.2)
Incidence (95% CIs)	0.4 (0.1–1.3)	1.2 (0.7–1.9)	2.5 (1.8–3.4)	3.2 (2.4–4.2)	1.4 (0.2–10.1)	4.5 (2.1–9.4)	10.9 (7.1–16.8)	13.7 (9.6–19.6)	0.3 (0.1–1.2)	0.7 (0.4–1.4)	1.3 (0.9–2.1)	1.6 (1.1–2.4)
Mean severity (95% CIs)	39 (13–121)	12 (7–20)	13 (9–18)	22 (17–29)	96 (14–682)	21 (10–43)	12 (8–18)	23 (16–34)	11 (3–42)	4 (2–8)	14 (9–22)	20 (13–30)
Median severity (IQR)	20 (10–58)	5 (3–12)	8 (4–19)	12 (6–28)	96 (96–96)	14 (3–37)	10 (3–14)	9 (6–29)	10 (6–15)	4 (2–5)	8 (4–20)	13 (8–26)
Burden (95% CIs)	16 (5–49)	14 (8–23)	32 (24–44)	68 (52–90)	136 (19–965)	92 (44–193)	130 (85–199)	310 (216–446)	3 (1–13)	3 (1–6)	19 (12–30)	32 (21–48)

Injury incidence, the number of injuries per 1000 exposure hours (95% CI). Severity, days lost to injury (IQR). Injury burden, the number of days lost per 1000 exposure hours (95% CI). – indicates that no time-loss injuries occurred within this category. N.B. One U16 ACL injury sustained in match-play resulting in 419 days absence was removed when calculating injury burden due to its disproportionate influence on severity (12.4 standard deviations away from mean severity in U16) and burden estimates.

Figure 1. Risk matrix illustrating the burden of time-loss injuries (days lost per 1000 exposure hours) sustained in matches and training for all age groups. The y-axis represents mean severity (days lost to injury, log scale) whilst the x-axis represents mean incidence (number of injuries per 1000 hours, log scale). The vertical and horizontal error bars represent 95% Poisson CIs. The dashed line represents mean burden for training whilst the two-dashed line represents the mean burden for match-play. The grey area surrounding the average lines for training and matches represent 95% Poisson CIs. N.B. One U16 ACL injury sustained in match-play resulting in 419 days absence was removed when calculating burden in this matrix due to its disproportionate influence on severity (12.4 standard deviations away from mean severity in U16) and burden estimates.