The Risk Factors for Musculoskeletal Injuries in Thoroughbred Racehorses in Queensland, Australia: How These Vary for Two-Year-Old and Older Horses and with Type of Injury
Abstract
:Simple Summary
Abstract
1. Introduction
2. Materials and Methods
2.1. Recruitment of Participants
2.2. Study Design
2.3. Data Collection
- (1)
- Cases of MSI and the diagnosis
- (2)
- One control matched to every case of MSI
- (3)
- Risk factors for MSI
2.3.1. Case Selection
2.3.2. Control Selection
2.3.3. Definitions of Speeds and Terminology
2.3.4. Risk Factors for Musculoskeletal Injury
- (1)
- Population characteristics
- (2)
- General racing and training history
- (3)
- High-speed exercise history
- (4)
- Racing career and performance indices
Population Characteristics
General Racing and Training History
High-Speed Exercise History
- (1)
- The total number of days (events) exercised at “three-quarter pace and above” (faster than 13 m/s; 15 s/furlong; 800 m/min; 48 km/h)
- (2)
- The total distance (furlongs) travelled at “three-quarter pace and above”
- (3)
- The average distance per event at “three-quarter pace and above”
- (4)
- The total number of days (events) exercised at “gallop” (faster than 15 m/s; 13 s/furlong; 900 m/min; 55 km/h) during trackwork
- (5)
- The total distance (furlongs) travelled at “gallop” during trackwork
- (6)
- The average distance per event at “gallop” during trackwork
- (7)
- The total distance (furlongs) travelled in jump-outs (non-official trials)
- (8)
- The total distance (furlongs) travelled in official trials
- (9)
- The total distance (furlongs) travelled in races
- (10)
- The combined distance travelled for jump-outs, official trials, and races
- (11)
- The total distance travelled at “gallop” during trackwork, jump-outs, official trials, and races (furlongs)
Racing Career and Performance Indices
2.4. Power Calculations
2.5. Data Analysis
Analysis by Type of Musculoskeletal Injury
- (1)
- Dorsal metacarpal disease
- (2)
- Carpal and fetlock injuries
- (3)
- Tendon and ligament injuries
- (4)
- Fractures
- (5)
- Other
3. Results
3.1. Characteristics of Cases and Controls
3.2. Univariable Analysis of Risk Factors for Musculoskeletal Injury
3.3. Multivariable Analysis of Risk Factors for Musculoskeletal Injury
3.4. Analysis by Type of Musculoskeletal Injury
4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Conflicts of Interest
Appendix A
Horses of All Ages by Type of Injury | Univariable OR (95% CI) | p-Value † |
---|---|---|
Dam parity | ||
Dorsal metacarpal disease (N = 47) | 0.41 | |
1 | ref | |
2–3 | 0.34 (0.09, 1.35) | 0.13 |
4 | 0.38 (0.08, 1.89) | 0.24 |
5–14 | 0.30 (0.07, 1.30) | 0.11 |
Other types of injuries (N = 155) | 0.35 | |
1 | reference | |
2–3 | 0.64 (0.32, 1.23) | 0.21 |
4 | 0.75 (0.34, 1.66) | 0.48 |
5–14 | 0.53 (0.25, 1.10) | 0.40 |
Distance 3/4 pace and above last 4 weeks (furlongs) | ||
Dorsal metacarpal disease (N = 47) | 0.24 | |
0–14 | reference | |
15–24 | 3.73 (0.99, 14.08) | 0.05 |
25–31 | 1.82 (0.30, 10.86) | 0.51 |
32–62 | 2.09 (0.27, 16.41) | 0.48 |
Carpal and fetlock injuries (N = 41) | 0.48 | |
0–14 | reference | |
15–24 | 1.69 (0.43, 6.60) | 0.45 |
25–31 | 0.65 (1.52, 2.81) | 0.57 |
32–62 | 0.48 (0.09, 2.63) | 0.40 |
Tendon and ligament injuries (N = 40) | 0.44 | |
0–14 | reference | |
15–24 | 2.25 (0.39, 13.06) | 0.37 |
25–31 | 0.96 (0.18, 5.12) | 0.96 |
32–62 | 0.45 (0.09, 2.29) | 0.34 |
Fractures and stress fractures (N = 33) | 0.07 | |
0–14 | reference | |
15–24 | 5.14 (0.59, 44.90) | 0.14 |
25–31 | 0.39 (0.03, 4.37) | 0.44 |
32–62 | 0.12 (0.01, 1.15) | 0.07 |
Other (N = 41) | 0.17 | |
0–14 | reference | |
15–24 | 0.39 (0.07, 2.13) | 0.28 |
25–31 | 0.18 (0.02, 1.32) | 0.09 |
32–62 | 0.08 (0.01, 0.74) | 0.03 |
Total distance galloped last 4 weeks (furlongs) | ||
Dorsal metacarpal disease (N = 47) | 0.25 | |
0–5 | reference | |
6–11 | 1.22 (0.36, 4.16) | 0.74 |
12–19 | 4.62 (0.92, 23.24) | 0.06 |
20–33 | 3.60 (0.76, 17.11) | 0.11 |
Carpal and fetlock injuries (N = 41) | 0.30 | |
0–5 | reference | |
6–11 | 1.61 (0.30, 8.65) | 0.58 |
12–19 | 3.52 (0.75, 16.58) | 0.11 |
20–33 | 1.02 (0.28, 3.70) | 0.30 |
Tendon and ligament injuries (N = 40) | 0.57 | |
0–5 | reference | |
6–11 | 1.57 (0.24, 10.32) | 0.57 |
12–19 | 3.26 (0.47, 22.84) | 0.23 |
20–33 | 1.11 (0.26, 4.80) | 0.88 |
Fractures and stress fractures (N = 33) | 0.38 | |
0–5 | reference | |
6–11 | 0.24 (0.02, 3.39) | 0.29 |
12–19 | 1.15 (0.22, 6.09) | 0.87 |
20–33 | 0.28 (0.04, 2.00) | 0.21 |
Other (N =41) | 0.60 | |
0–5 | reference | |
6–11 | 2.00 (0.18, 22.06) | 0.57 |
12–19 | 0.79 (0.14, 4.54) | 0.79 |
20–33 | 0.39 (0.08, 1.82) | 0.23 |
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Variable | Horses of All Ages | Two-Year-Old Horses | Horses Three Years and Older | ||||
---|---|---|---|---|---|---|---|
Cases (n = 202) | Controls (n = 202) | Cases (n = 103) | Controls (n = 103) | Cases (n = 99) | Controls (n = 99) | ||
Population characteristics | |||||||
Median (IQR) | Median (IQR) | Median (IQR) | Median (IQR) | Median (IQR) | Median (IQR) | p-value # | |
Dam Age (years) | 9 (7–12) | 10 (8–12) | 9 (7–11) | 10 (8–12) | 9 (7–13) | 10 (7–12) | 0.24 |
Dam Parity | 3 (2–5) | 4 (2–6) | 3 (2–4) | 4 (2–6) | 4 (2–6) | 3 (2–6) | 0.52 |
N (%) | N (%) | N (%) | N (%) | N (%) | N (%) | p-value # | |
Sex | <0.001 | ||||||
Entire males | 34 (17.0) | 34 (17) | 31 (30) | 33 (32) | 3 (3) | 1 (1) | |
Geldings | 82 (40) | 88 (43) | 24 (23) | 23 (22) | 58 (59) | 65 (66) | |
Females | 86 (43) | 80 (40) | 48 (47) | 47 (46) | 38 (38) | 33 (33) | |
General racing and training history | |||||||
N (%) | N (%) | N (%) | N (%) | N (%) | N (%) | p-value # | |
Started in a race | <0.001 | ||||||
Yes | 97 (48) | 105 (52) | 13 (13) | 14 (14) | 84 (85) | 91 (92) | |
No | 105 (52) | 97 (48) | 90 (87) | 89 (86) | 15 (15) | 8 (8) | |
Median (IQR) | Median (IQR) | Median (IQR) | Median (IQR) | Median (IQR) | Median (IQR) | p–value # | |
Length of training prep (wks) | 9 (6–14) | 8 (5–15) | 7 (5–10) | 6 (5–8) | 13 (8–24) | 14 (8–20) | <0.001 |
Length of pre-training (wks) | 0 (0–2) | 0 (0–2) | 2 (0–3) | 0 (0–3) | 0 (0–0) | 0 (0–0) | <0.001 |
Total prep length (wks) | 10 (8–15) | 10 (7–15) | 9 (7–11) | 8 (6–10) | 14 (8–24) | 14 (9–20) | <0.001 |
Days slow last 4 wks | 15 (13–17) | 16 (15–18) | 15 (13–17) | 17 (15–19) | 15 (13–17) | 16 (15–17) | 0.06 |
Days water-walker last 4 wks | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0.01 |
Days treadmill last 4 wks | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0.24 |
High-speed exercise history | |||||||
Median (IQR) | Median (IQR) | Median (IQR) | Median (IQR) | Median (IQR) | Median (IQR) | p-value # | |
Days 3/4 pace and above last 4 wks | 6 (4–7) | 7 (5–8) | 6 (4–7) | 6 (3–7) | 6 (5–8) | 7 (6–8) | <0.001 |
Dist 3/4 pace and above last 4 wks (f) | 24 (15–31) | 27 (16–34) | 18 (10–24) | 20 (9–26) | 30 (22–37) | 33 (29–40) | <0.001 |
Dist 3/4 pace and above per event (f) | 4 (3–5) | 4 (3–5) | 3 (3–4) | 3 (3–4) | 5 (4–5) | 5 (4–5) | <0.001 |
Days track gallop last 4 wks | 5 (2–6) | 5 (1–6) | 3 (1–5) | 3 (0–5) | 6 (4–7) | 6 (5–7) | <0.001 |
Dist track gallop last 4 wks (f) | 12 (4–16) | 12 (2–18) | 6 (2–12) | 5 (0–12) | 16 (11–19) | 18 (12–21) | <0.001 |
Dist track gallop per event (f) | 2 (2–3) | 2 (1–3) | 2 (1–2) | 2 (0–2) | 3 (2–3) | 3 (2–3) | <0.001 |
Dist jump-outs last 4 wks (f) | 0 (0–2) | 0 (0–0) | 0 (0–2) | 0 (0–2) | 0 (0–0) | 0 (0–0) | <0.001 |
Dist trials last 4 wks (f) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0.07 |
Dist races last 4 wks (f) | 0 (0–5) | 0 (0–6) | 0 (0–0) | 0 (0–0) | 4 (0–7) | 5 (0–11) | <0.001 |
Dist jump-outs, trials and races (f) | 4 (0–8) | 4 (0–10) | 2 (0–5) | 0 (0–4) | 6 (0–10) | 7 (0–12) | <0.001 |
Total dist galloped (track, jump-outs, trials, races) | 16 (4–22) | 16 (2–28) | 8 (3–17) | 6 (0–17) | 21 (16–30) | 24 (12–33) | <0.001 |
Racing career and performance indices | |||||||
N (%) | N (%) | N (%) | N (%) | N (%) | N (%) | p-value # | |
Started as two-year-old | |||||||
Yes | 48 (49) | 56 (53) | † | † | 35 (42) | 43 (47) | † |
No | 49 (51) | 49 (47) | † | † | 49 (58) | 48 (53) | † |
Median (IQR) | Median (IQR) | Median (IQR) | Median (IQR) | Median (IQR) | Median (IQR) | p-value # | |
No. starts as two-year-old | 2 (1–4) | 3 (2–5) | † | † | 2 (1–4) | 2 (2–5) | † |
Age at first race (years) | 3 (2–3) | 2 (2–3) | † | † | 3 (2–3) | 3 (2–3) | † |
Length of career to date (months) | 17 (8–29) | 17 (8–27) | 3 (1–3) | 5 (3–8) | 19 (12–30) | 20 (10–29) | <0.001 |
No. of starts | 10 (3–19) | 9 (4–20) | 2 (2–3) | 3 (2–5) | 11 (5–22) | 11 (6–21) | <0.001 |
Starts per 12 months over career | 8 (5–11) | 8 (6–10) | 12 (8–12) | 8 (6–10) | 8 (5–10) | 8 (6–10) | 0.11 |
No. of races won | 1 (0–3) | 2 (0–3) | 1 (0–1) | 0 (0–1) | 2 (0–4) | 2 (1–4) | <0.001 |
% of races won | 17 (0–25) | 15 (0–24) | 50 (0–50) | 0 (0–25) | 16 (0–21) | 15 (7–24) | 0.30 |
No. of races 1st, 2nd or 3rd place | 3 (2–9) | 4 (2–9) | 2 (1–2) | 1 (0–2) | 4 (2–9) | 6 (2–10) | <0.001 |
% of races 1st, 2nd or 3rd place | 44 (33–55) | 46 (31–58) | 67 (50–100) | 50 (0–71) | 43 (30–53) | 45 (33–56) | 0.11 |
Total dist raced (5 f/1 km) | 11 (3–26) | 11 (5–26) | 2 (2–3) | 3 (2–5) | 14 (6–28) | 14 (7–29) | <0.001 |
Average dist per start (f) | 6 (6–7) | 6 (6–7) | 5 (5–6) | 5 (5–6) | 6 (6–7) | 6 (6–7) | <0.001 |
Total prizemoney ($1000 AUD) | 33 (10–83) | 41 (12–89) | 26 (10–51) | 13 (2–67) | 34 (10–99) | 46 (16–90) | 0.03 |
Prizemoney per start ($1000 AUD) | 4 (1–6) | 4 (2–8) | 13 (3–25) | 5 (0–18) | 3 (1–5) | 4 (2–7) | 0.06 |
Variable | Horses of All Ages | p-Value † | Two-Year-Old Horses | p-Value † | Horses Three Years and Older | p-Value † |
---|---|---|---|---|---|---|
Univariable OR (95% CI) | Univariable OR (95% CI) | Univariable OR (95% CI) | ||||
Population characteristics | ||||||
Dam Age (years) | 0.65 | 0.28 | 0.52 | |||
4–6 | reference | reference | reference | |||
7–8 | 1.09 (0.55, 2.16) | 0.81 | 1.82 (0.59, 5.55) | 0.30 | 0.88 (0.35, 2.21) | 0.79 |
9–11 | 0.79 (0.44, 1.42) | 0.42 | 0.80 (0.36, 1.79) | 0.59 | 0.74 (0.30, 1.79) | 0.50 |
12–27 | 0.98 (0.52, 1.84) | 0.94 | 0.72 (0.29, 1.79) | 0.48 | 1.27 (0.52, 3.12) | 0.60 |
Dam Parity | 0.13 | 0.02 | 0.89 | |||
1 | reference | reference | reference | |||
2–3 | 0.56 (0.30, 1.03) | 0.06 | 0.30 (0.12, 0.77) | 0.01 | 1.11 (0.45, 2.73) | 0.82 |
4 | 0.65 (0.32, 1.32) | 0.23 | 0.28 (0.09, 0.84) | 0.02 | 1.44 (0.53, 3.94) | 0.48 |
5-14 | 0.47 (0.25, 0.90) | 0.02 | 0.19 (0.07, 0.52) | 0.001 | 1.18 (0.46, 2.99) | 0.73 |
Sex | 0.76 | 0.95 | 0.45 | |||
Entire males | reference | reference | reference | |||
Geldings | 0.91 (0.48, 1.71) | 0.76 | 1.11 (0.52, 2.34) | 0.79 | 0.33 (0.03, 3.20) | 0.34 |
Females | 1.09 (0.58, 2.02) | 0.79 | 1.09 (0.56, 2.15) | 0.79 | 0.44 (0.04, 4.61) | 0.49 |
General racing and training history | ||||||
Started in a race | 0.17 | 0.82 | 0.08 | |||
Yes | reference | reference | reference | |||
No | 1.62 (0.81, 3.23) | 0.17 | 1.11 (0.45, 2.73) | 0.82 | 2.75 (0.88, 8.64) | 0.08 |
Total preparation length (weeks) | 0.15 | 0.07 | 0.47 | |||
2–7 | reference | reference | reference | |||
8–9 | 2.04 (1.00, 4.14) | 0.05 | 1.96 (0.77, 5.02) | 0.16 | 2.23 (0.72, 6.88) | 0.16 |
10–14 | 1.91 (1.02, 3.60) | 0.05 | 3.34 (1.35, 8.24) | 0.01 | 1.03 (0.40, 2.68) | 0.95 |
15–48 | 1.59 (0.75, 3.34) | 0.22 | 1.50 (0.44, 5.13) | 0.52 | 1.25 (0.45, 3.48) | 0.66 |
Days slow last 4 weeks | <0.001 | <0.001 | 0.01 | |||
0–12 | reference | reference | reference | |||
13–15 | 0.45 (0.21, 0.99) | 0.05 | 0.92 (0.31, 2.69) | 0.88 | 0.22 (0.06, 0.76) | 0.02 |
16–17 | 0.13 (0.06, 0.32) | <0.001 | 0.19 (0.06, 0.62) | 0.01 | 0.09 (0.02, 0.35) | 0.001 |
18–24 | 0.13 (0.05, 0.33) | <0.001 | 0.15 (0.04, 0.56) | <0.001 | 0.11 (0.03, 0.45) | 0.002 |
Days water-walker last 4 weeks | 0.41 | 0.37 | 1.00 | |||
0–1 | reference | reference | reference | |||
2–24 | 0.63 (0.20, 1.91) | 0.41 | 0.57 (0.17, 1.95) | 0.37 | 1.00 (0.06, 15.99) | 1.00 |
Days treadmill last 4 weeks | 0.42 | 0.66 | ||||
0–1 | reference | reference | ||||
2–12 | 0.50 (0.09, 2.73) | 0.42 | 0.67 (0.11, 3.99) | 0.66 | ||
High-speed exercise history | ||||||
Days 3/4 pace and above last 4 weeks | 0.02 | 0.10 | 0.09 | |||
0–3 | reference | reference | reference | |||
4–5 | 1.99 (0.95, 4.16) | 0.07 | 1.93 (0.79, 4.69) | 0.15 | 2.82 (0.65, 12.33) | 0.17 |
6–7 | 1.46 (0.75, 2.84) | 0.27 | 2.22 (0.92, 5.37) | 0.08 | 0.82 (0.28, 2.41) | 0.71 |
8–12 | 0.65 (0.32, 1.31) | 0.23 | 0.69 (0.23, 2.05) | 0.50 | 0.52 (0.18, 1.48) | 0.22 |
Distance 3/4 pace and above last 4 weeks (furlongs) | <0.001 | 0.09 | 0.01 | |||
0–14 | reference | reference | reference | |||
15–24 | 1.84 (0.97, 3.48) | 0.06 | 1.53 (0.77, 3.03) | 0.22 | 5.52 (0.89, 34.21) | 0.07 |
25–31 | 0.66 (0.31, 1.39) | 0.27 | 0.40 (0.13, 1.20) | 0.10 | 1.41 (0.43, 4.68) | 0.57 |
32–62 | 0.33 (0.15, 0.72) | 0.01 | 0.61 (0.15, 2.41) | 0.48 | 0.41 (0.15, 1.17) | 0.10 |
Distance 3/4 pace and above per event (furlongs) | 0.35 | 0.62 | 0.79 | |||
0–2 | reference | reference | reference | |||
3 | 1.35 (0.72, 2.54) | 0.35 | 1.24 (0.61, 2.53) | 0.55 | 1.55 (0.34, 6.99) | 0.57 |
4–5 | 1.15 (0.56, 2.37) | 0.71 | 2.03 (0.71, 5.84) | 0.71 | 0.94 (0.25, 3.49) | 0.92 |
6–11 | 0.66 (0.27, 1.59) | 0.35 | 0.86 (0.22, 3.28) | 0.82 | ||
Days track gallop last 4 weeks | 0.31 | 0.32 | 0.41 | |||
0–1 | reference | reference | reference | |||
2–4 | 1.62 (0.90, 2.89) | 0.11 | 1.81 (0.91, 3.62) | 0.09 | 1.31 (0.42, 4.07) | 0.64 |
5–6 | 1.17 (0.55, 2.47) | 0.68 | 1.08 (0.38, 3.03) | 0.89 | 1.17 (0.36, 3.77) | 0.79 |
7–9 | 0.97 (0.51, 1.85) | 0.94 | 1.77 (0.65, 4.82) | 0.27 | 0.65 (0.25, 1.65) | 0.36 |
Distance track gallop last 4 weeks (furlongs) | 0.04 | 0.53 | 0.05 | |||
0–5 | reference | reference | reference | |||
6–11 | 1.40 (0.73, 2.68) | 0.31 | 1.71 (0.80, 3.67) | 0.17 | 0.77 (0.21, 2.84) | 0.69 |
12–19 | 1.49 (0.79, 2.79) | 0.22 | 1.42 (0.59, 3.41) | 0.43 | 1.29 (0.49, 3.41) | 0.60 |
20–33 | 0.57 (0.26, 1.25) | 0.16 | 0.91 (0.14, 6.07) | 0.93 | 0.45 (0.16, 1.24) | 0.12 |
Distance track gallop per event (furlongs) | 0.50 | 0.66 | 0.70 | |||
0–1.4 | reference | reference | reference | |||
1.5–2 | 1.53 (0.80, 2.93) | 0.20 | 1.64 (0.75, 3.56) | 0.21 | 1.25 (0.38, 4.11) | 0.71 |
2.1–2.9 | 1.33 (0.70, 2.52) | 0.39 | 1.34 (0.54, 3.31) | 0.53 | 1.15 (0.43, 3.09) | 0.78 |
3–10.6 | 1.03 (0.53, 2.02) | 0.92 | 1.40 (0.52, 3.81) | 0.51 | 0.78 (0.28, 2.17) | 0.64 |
Distance jump-outs last 4 weeks (furlongs) | 0.07 | 0.12 | 0.37 | |||
0–1 | reference | reference | reference | |||
2–9.3 | 1.75 (0.95, 3.23) | 0.07 | 1.75 (0.86, 3.56) | 0.12 | 1.75 (0.51, 5.98) | 0.37 |
Distance trials last 4 weeks (furlongs) | 0.57 | 0.28 | 0.85 | |||
0–1 | reference | reference | reference | |||
2–14.2 | 1.17 (0.67, 2.05) | 0.57 | 1.63 (0.67, 3.92) | 0.28 | 0.93 (0.45, 1.93) | 0.85 |
Distance races last 4 weeks (furlongs) | 0.78 | 0.78 | 0.33 | |||
0–1 | reference | reference | reference | |||
2–22.2 | 0.86 (0.29, 2.55) | 0.78 | 0.86 (0.29, 2.55) | 0.78 | 0.73 (0.38, 1.38) | 0.33 |
Combined distance jump-outs, trials and races (furlongs) | 0.01 | 0.08 | 0.09 | |||
0–3.9 | reference | reference | reference | |||
4–9.9 | 1.84 (1.03, 3.28) | 0.04 | 2.30 (0.93, 5.68) | 0.07 | 1.61 (0.74, 3.50) | 0.23 |
10–22.2 | 0.72 (0.38, 1.36) | 0.31 | 0.60 (0.20, 1.82) | 0.37 | 0.73 (0.32, 1.64) | 0.44 |
Total distance galloped (track, jump-outs, trials, races) | 0.04 | 0.30 | 0.70 | |||
0–5 | reference | reference | reference | |||
6–11 | 1.03 (0.50, 2.15) | 0.93 | 1.31 (0.57, 3.09) | 0.53 | 0.48 (0.10, 2.36) | 0.37 |
12–19 | 2.34 (1.14, 4.78) | 0.02 | 2.00 (0.83, 4.84) | 0.12 | 2.71 (0.77, 9.53) | 0.12 |
20–33 | 0.94 (0.50, 1.77) | 0.86 | 1.40 (0.54, 3.61) | 0.49 | 0.70 (0.28, 1.76) | 0.45 |
Racing career and performance indices | ||||||
Number starts as two-year-old | 0.50 | 0.60 | ||||
0 | reference | reference | ||||
1–2 | 0.85 (0.40, 1.81) | 0.68 | 0.78 (0.36, 1.68) | 0.52 | ||
3–5 | 0.45 (0.16, 1.26) | 0.13 | 0.50 (0.18, 1.41) | 0.19 | ||
6–9 | 0.65 (0.16, 2.54) | 0.53 | 0.82 (0.20, 3.41) | 0.78 | ||
Age at first race (years) | 0.19 | 0.19 | ||||
2 | reference | reference | ||||
3 | 1.31 (0.68, 2.52) | 0.41 | 1.31 (0.68, 2.52) | 0.41 | ||
4 | 3.61 (0.90, 14.42) | 0.07 | 3.61 (0.90, 14.42) | 0.07 | ||
Length of career to date (months) | 0.99 | 0.85 | ||||
1–7 | reference | reference | ||||
8–16 | 1.16 (0.40, 3.33) | 0.79 | 1.68 (0.52, 5.39) | 0.39 | ||
17–28 | 1.06 (0.35, 3.21) | 0.92 | 1.33 (0.42, 4.20) | 0.63 | ||
29–68 | 1.19 (0.33, 4.31) | 0.79 | 1.48 (0.39, 5.62) | 0.58 | ||
Number of starts | 0.62 | 0.70 | ||||
1–3 | reference | reference | ||||
4–8 | 0.72 (0.24, 2.20) | 0.57 | 0.99 (0.30, 3.30) | 0.99 | ||
9–19 | 0.81 (0.24, 2.76) | 0.73 | 1.01 (0.28, 3.61) | 0.98 | ||
20–67 | 0.43 (0.10, 1.93) | 0.27 | 0.55 (0.12, 2.58) | 0.45 | ||
Starts per 12 months over career duration | 0.46 | 0.44 | ||||
0.4–5.7 | reference | reference | ||||
5.8–8.2 | 0.46 (0.18, 1.21) | 0.12 | 0.45 (0.16, 1.23) | 0.12 | ||
8.3–10 | 0.73 (0.29, 1.80) | 0.49 | 0.72 (0.29, 1.81) | 0.49 | ||
10.1–24 | 0.69 (0.26, 1.81) | 0.49 | 0.83 (0.31, 2.24) | 0.72 | ||
Number of races won | 0.72 | 0.68 | ||||
0 | reference | reference | ||||
1–2 | 0.57 (0.22, 1.48) | 0.25 | 0.53 (0.19, 1.47) | 0.22 | ||
3–5 | 0.63 (0.20, 2.00) | 0.44 | 0.60 (0.18, 1.96) | 0.39 | ||
6–13 | 0.62 (0.13, 2.96) | 0.55 | 0.58 (0.12, 2.87) | 0.51 | ||
% of races won | 0.26 | 0.19 | ||||
0 | reference | reference | ||||
1–15 | 0.42 (0.14, 1.29) | 0.14 | 0.44 (0.14, 1.40) | 0.17 | ||
16–25 | 0.84 (0.28, 2.49) | 0.76 | 0.93 (0.29, 2.96) | 0.90 | ||
26–100 | 0.63 (0.21, 1.84) | 0.40 | 0.52 (0.16, 1.67) | 0.28 | ||
Number of races 1st, 2nd or 3rd place | 0.49 | 0.47 | ||||
0 | reference | reference | ||||
1–2 | 1.86 (0.50, 6.92) | 0.36 | 1.88 (0.50, 7.06) | 0.35 | ||
3–6 | 1.08 (0.25, 4.62) | 0.91 | 1.04 (0.24, 4.50) | 0.96 | ||
7–27 | 0.87 (0.19, 4.02) | 0.86 | 0.85 (0.18, 3.95) | 0.83 | ||
% of races 1st, 2nd or 3rd place | 0.50 | 0.38 | ||||
0 | reference | reference | ||||
1–30 | 2.40 (0.56, 10.20) | 0.24 | 2.70 (0.62, 11.86) | 0.19 | ||
31–50 | 1.19 (0.30, 4.65) | 0.81 | 1.17 (0.30, 4.63) | 0.82 | ||
51–100 | 1.29 (0.34, 4.97) | 0.71 | 1.21 (0.31, 4.69) | 0.78 | ||
Total distance raced (5 furlongs/1 km) | 0.87 | 0.89 | ||||
1–4.3 | reference | reference | ||||
4.4–11.2 | 0.81 (0.27, 2.44) | 0.70 | 1.13 (0.34, 3.74) | 0.84 | ||
11.3–26.5 | 0.66 (0.19, 2.21) | 0.50 | 0.84 (0.24, 2.97) | 0.79 | ||
26.6–139.9 | 0.53 (0.12, 2.40) | 0.41 | 0.69 (0.15, 3.27) | 0.64 | ||
Average distance per start (furlongs) | 0.13 | 0.15 | ||||
4.5–5.6 | reference | reference | ||||
5.7–6.0 | 0.41 (0.13, 1.27) | 0.12 | 0.53 (0.16, 1.69) | 0.28 | ||
6.1–6.8 | 1.00 (0.27, 3.63) | 0.99 | 1.39 (0.35, 5.51) | 0.64 | ||
6.9–10.4 | 0.43 (0.12, 1.55) | 0.20 | 0.57 (0.15, 2.13) | 0.41 | ||
Total prizemoney ($1000 AUD) | 0.25 | 0.40 | ||||
0–11.0 | reference | reference | ||||
11.1–36.9 | 0.43 (0.13, 1.42) | 0.17 | 0.46 (0.14, 1.54) | 0.21 | ||
37.0–88.6 | 0.28 (0.07, 1.02) | 0.05 | 0.34 (0.09, 1.27) | 0.11 | ||
88.7–1039.5 | 0.26 (0.06, 1.09) | 0.07 | 0.30 (0.07, 1.27) | 0.10 | ||
Prizemoney per start ($1000 AUD) | 0.05 | 0.06 | ||||
0–1.8 | reference | reference | ||||
1.9–3.7 | 0.16 (0.04, 0.62) | 0.01 | 0.16 (0.04, 0.62) | 0.01 | ||
3.8–6.8 | 0.25 (0.07, 0.92) | 0.04 | 0.25 (0.07, 0.90) | 0.03 | ||
6.9–67.2 | 0.17 (0.04, 0.69) | 0.01 | 0.18 (0.04, 0.74) | 0.02 |
Population Characteristics | Horses of All Ages | Two-Year-Old Horses | Horses Three Years and Older | |||
---|---|---|---|---|---|---|
Adjusted OR (95% CI) | p-Value † | Adjusted OR (95% CI) | p-Value † | Adjusted OR (95% CI) | p-Value † | |
Dam Parity | 0.01 | 0.01 | ||||
1 | reference | reference | ||||
2–3 | 0.55 (0.25, 1.22) | 0.14 | 0.19 (0.05, 0.70) | 0.01 | ||
4 | 0.62 (0.25, 1.54) | 0.30 | 0.16 (0.03, 0.76) | 0.02 | ||
5–14 | 0.27 (0.12, 0.64) | 0.003 | 0.08 (0.02, 0.36) | 0.001 | ||
General racing and training history | ||||||
Total preparation length (weeks) | 0.01 | 0.04 | ||||
2–7 | reference | reference | ||||
8–9 | 4.77 (1.69, 13.43) | 0.003 | 5.17 (1.27, 21.02) | 0.02 | ||
10–14 | 4.73 (1.65, 13.52) | 0.004 | 8.05 (1.92, 33.76) | 0.004 | ||
15–48 | 5.56 (1.59, 19.46) | 0.01 | 2.61 (0.51, 13.44) | 0.25 | ||
Days slow last 4 weeks | <0.001 | 0.004 | 0.005 | |||
0–12 | reference | reference | reference | |||
13–15 | 0.31 (0.12, 0.84) | 0.02 | 1.04 (0.27, 4.00) | 0.96 | 0.19 (0.05, 0.74) | 0.02 |
16–17 | 0.10 (0.03, 0.28) | <0.001 | 0.20 (0.05, 0.83) | 0.03 | 0.08 (0.02, 0.36) | 0.001 |
18–24 | 0.09 (0.03, 0.28) | <0.001 | 0.14 (0.03, 0.65) | 0.01 | 0.08 (0.02, 0.37) | 0.001 |
High-speed exercise history | ||||||
Distance 3/4 pace and above last 4 weeks (furlongs) | <0.001 | 0.05 | 0.007 | |||
0–14 | reference | reference | reference | |||
15–24 | 0.86 (0.30, 2.52) | 0.79 | 1.15 (0.43, 3.08) | 0.78 | 10.02 (1.34, 75.77) | 0.03 |
25–31 | 0.15 (0.04, 0.64) | 0.01 | 0.12 (0.02, 0.70) | 0.02 | 2.06 (0.49, 8.60) | 0.32 |
32–62 | 0.06 (0.01, 0.26) | <0.001 | 0.13 (0.02, 0.91) | 0.04 | 0.53 (0.14, 1.93) | 0.33 |
Total distance galloped (track, jump-outs, trials, races) | 0.08 | |||||
0–5 | reference | |||||
6–11 | 0.85 (0.26, 2.77) | 0.79 | ||||
12–19 | 3.85 (1.04, 14.25) | 0.04 | ||||
20–33 | 1.87 (0.51, 6.82) | 0.34 |
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Crawford, K.L.; Finnane, A.; Phillips, C.J.C.; Greer, R.M.; Woldeyohannes, S.M.; Perkins, N.R.; Kidd, L.J.; Ahern, B.J. The Risk Factors for Musculoskeletal Injuries in Thoroughbred Racehorses in Queensland, Australia: How These Vary for Two-Year-Old and Older Horses and with Type of Injury. Animals 2021, 11, 270. https://doi.org/10.3390/ani11020270
Crawford KL, Finnane A, Phillips CJC, Greer RM, Woldeyohannes SM, Perkins NR, Kidd LJ, Ahern BJ. The Risk Factors for Musculoskeletal Injuries in Thoroughbred Racehorses in Queensland, Australia: How These Vary for Two-Year-Old and Older Horses and with Type of Injury. Animals. 2021; 11(2):270. https://doi.org/10.3390/ani11020270
Chicago/Turabian StyleCrawford, Kylie L., Anna Finnane, Clive J. C. Phillips, Ristan M. Greer, Solomon M. Woldeyohannes, Nigel R. Perkins, Lisa J. Kidd, and Benjamin J. Ahern. 2021. "The Risk Factors for Musculoskeletal Injuries in Thoroughbred Racehorses in Queensland, Australia: How These Vary for Two-Year-Old and Older Horses and with Type of Injury" Animals 11, no. 2: 270. https://doi.org/10.3390/ani11020270
APA StyleCrawford, K. L., Finnane, A., Phillips, C. J. C., Greer, R. M., Woldeyohannes, S. M., Perkins, N. R., Kidd, L. J., & Ahern, B. J. (2021). The Risk Factors for Musculoskeletal Injuries in Thoroughbred Racehorses in Queensland, Australia: How These Vary for Two-Year-Old and Older Horses and with Type of Injury. Animals, 11(2), 270. https://doi.org/10.3390/ani11020270