Increased pitches per season and game were associated with higher risks of elbow and shoulder pain in adolescent baseball pitchers. A study found that pitching 300-599 pitches in a season was associated with a lower risk of elbow pain compared to less than 300 pitches, but a higher 600+ pitches was associated with a higher risk. Pitching 75-99 pitches or 100+ pitches in a game was associated with higher risks of shoulder pain compared to less than 25 pitches. The fastball pitch placed the most stress on the elbow and shoulder joints and increased the risks of pain. Developmental variations between youth makes it difficult to determine a definite level of risk from pitch count and type.

1. • Baseball is a generally safe sport; however, acute and
chronic injuries do occur. For pitchers, the majority of
these injuries involve overuse injuries of the elbow and
shoulder.1-3
• Overall, youth athletes are more susceptible to overuse
injuries of the shoulder and elbow due to incomplete bone
ossification, overloading stresses placed on the joints from
full-speed throwing motions, and general instability of the
glenohumeral joint with fatigue.1,4
In turn, this places
pitchers especially at risk of injury.5
• Currently, there is no one single risk factor increasing the
risk shoulder or elbow injury. However, in adolescent
baseball, rising pitch counts and specific pitch types
influence risk of injury, but how much is still under
investigation.
• Does pitch count /type increase the risk of shoulder and/or
elbow injuries in adolescent baseball pitchers?
• Articles examining the influence of pitch count/type on
shoulder/elbow injuries were identified from the
following electronic databases from January 2000 through
November 2013:
1. PubMed (www.pubmed.gov)
2. Cumulative Index to Nursing and Allied Health Literature
(CINAHL)
3. Science Direct
4. MEDLINE
• Key terms used included:
• “adolescent and baseball”
• “adolescent and pitch count or pitch type”
• “shoulder or elbow and injuries and adolescent”
• Studies could be either full reports or abstracts meeting
the inclusion criteria in table 1.
The Influence of Pitch Count and Type on Elbow and Shoulder Injuries
in Adolescent Baseball Pitchers: A Systematic Review
Nicole R. Miela, Julie C. Jamrog, Mitchell T. Irwin, & David C. Berry, PhD, AT, ATC
Saginaw Valley State University, University Center, MI
• Three reviewers independently assessed (Table 2) each
report according to the Strengthening in the Reporting of
Observational Studies in Epidemiology (STROBE) and
Physiotherapy Evidence Database (PEDro) scales.
• Three articles were observational studies.
• Average PEDro score for one clinical trial was 5.33±0.94.
• Olsen et al5
examined adolescent pitchers who underwent
shoulder or elbow surgery and age-matched controls and
found:
• Pitches per appearance yielded significance (p <0.001)
for shoulder (93.16±15.2 pitches) and elbow injuries
(85.2 ±23.8).
• Pitches per year showed significance (p <0.001) for
both shoulder and elbow injuries (2608.4 ± 1587.3,
2458.6 ± 1321.3).
• A controlled clinical trial6
to determine differences
between the fastball, curveball, and change-up found:
• The fastball produced the greatest values for elbow and
shoulder proximal force (461.9 ±163.2 N, 465.6 ±169.9
N), p <0.01.
• Data suggests that increased pitch counts per season and
game increases the occurrence of elbow and shoulder
pain, respectively.
• The fastball appears to place the most stress on both the
elbow and shoulder, while the sinker is more influential
on the elbow. This sheds light on what used to be simply
controversy regarding injury risk of certain pitches.9
• Pitching through pain and fatigue is NOT recommended
as it indicates an increased potential for overuse injuries
(OR 36.18, 95% CI 5.92-221.22).5,10
• Rates of biomechanical development vary individually.
These variances coupled with age-ranged
recommendations makes pinpointing when a pitcher is
able to throw a certain pitch difficult to determine.
• Increased awareness of the influence of pitch count and
type to coaches, parents, and athletes can be facilitated by
athletic trainers.
• Athletic trainers can promote the use of pitch tracking and
to identify athletes most at risk of injury.
• Through efficient pitch tracking and risk identification,
athletic trainers can work with the athlete, coaches, and
parents to determine the best course of injury prevention
or management for the athlete.
• Increased pitches per season yielded increased elbow
pain, while increased pitches per game yielded increased
shoulder pain. The fastball, slider, and sinker led to
increased joint pain as well. Developmental variances
among youth inhibits definite conclusions concerning the
degree of influence pitch count/type holds on injury rates.
1. Rice SG, Congeni JA. Baseball and softball. Pediatrics. 2012;129(3):e842-56.
2. American Academy of Pediatrics Committee on Sports Medicine and Fitness. Risk of injury from baseball and softball in children.
Pediatrics. 2001; 107:782-784.
3. Rizio L, Uribe JW. Overuse injuries of the upper extremity in baseball. Clin Sports Med. 2001; 20:453-468.
4. Dalton SE. Overuse injuries in adolescent athletes. Sports Med. 1992;13(1):58-70.
5. Olsen SJ, et al. Risk factors for shoulder and elbow injuries in adolescent baseball pitchers. Am J Sports Med. 2006;34(6):905-12.
6. Dun S, et al. A biomechanical comparison of youth baseball pitches: is the curveball potentially harmful?. Am J Sports Med.
2008;36(4):686-92.
7. Lyman S, et al. Longitudinal study of elbow and shoulder pain in youth baseball pitchers. Med Sci Sports Exerc. 2001;33(11):1803-
10.
8. Lyman S, et al. Effect of pitch type, pitch count, and pitching mechanics on risk of elbow and shoulder pain in youth baseball
pitchers. Am J Sports Med. 2002;30(4):463-8.
9. Fleisig GS, et al. Kinetic comparison among the fastball, curveball, change-up, and slider in collegiate baseball pitchers. Am J Sports
Med. 2006;34:423-430.
10. McLeod TCV, et al. National Athletic Trainers’ Association position statement: prevention of pediatric overuse injuries.
http://www.nata.org/sites/default/files/Pediatric-Overuse-Injuries.pdf. J Athl Train. 2011;46(2):206-220. Published April 2011.
Accessed November 22, 2013.
Crystal M. Lange
College of Health and
Human Services
Introduction
Clinical Question/Objective
Discussion
Clinical Application
Conclusion
References
Data Source
Data Extraction
Data Synthesis
Table 1. Inclusion Criteria.
1. Peer-reviewed cohort, descriptive epidemiology, case
control, cross-sectional, or controlled clinical trial
2. Full reports or abstracts published in English
3. Involved adolescents 13-18 years of age
4. Available abstract
5. Outcomes measuring the influence of pitch count/type
on shoulder and/or elbow injuries
Table 2. Data of Interest
1. Methods of observation/trial and descriptive data
2. Subjects and group divisions
3. Odds ratios and 95% confidence intervals referring to
influence of pitch count/type on shoulder/elbow injuries
Data Source
Lyman et al.5
Cumulative Pitches Elbow Pain OR
(95% CI)
P Shoulder Pain OR
(95% CI)
P
<300 Referent --- Referent <0.01
300-599 0.54 (0.32, 0.92) 0.02 0.40 (0.24, 0.65)
≥600 2.07 (0.68, 6.26) 0.20 0.13 (0.01, 1.10)
Age (M=10.8 years)
<10 yr Referent 0.02 Referent 0.13
10 yr 1.66 (0.71, 3.88) 0.55 (0.29, 1.03)
11 yr 2.60 (0.99, 6.81) 0.68 (0.28, 1.65)
≥12 yr 2.91 (1.14, 7.41) 0.41 (0.14, 1.15)
• The key findings of Lyman et al.7
are presented in table 3.
Table 3. Elbow and Shoulder Pain in Youth Baseball Pitchers
• Lyman et al’s8
effects of pitch type/count are in table 4.
Table 4. Effect of Pitch Type, Pitch Count, and Pitching Mechanics
Season Pitches to Date Elbow OR P Shoulder OR P
1-200 Referent <0.01 Referent <0.01
201-400 1.63 1.65
401-600 2.81 2.34
601-800 3.34 2.90
800+ 2.61 3.29
Game Pitch Counts
9-10 yo 1-24 Referent 0.67 Referent 0.01
25-49 1.20 0.97
50-74 1.40 1.11
75-99 0.91 1.32
100+ 1.33 2.01
11-12 yo 1-24 Referent 0.60 Referent 0.94
25-49 0.84 0.98
50-74 0.83 1.10
75-99 1.30 1.14
100+ 0.87 0.76
13-14 yo 1-24 Referent 0.06 Referent 0.06
25-49 1.12 1.51
50-74 1.38 1.65
75-99 1.59 2.17
100+ 2.22 2.15
Pitch Type and Age
Change-up 9-10 yo 1.41 0.36 0.65 0.20
11-12 yo 0.59 0.14 0.67 0.26
13-14 yo 0.69 0.37 1.10 0.83
Curveball 9-10 yo 1.35 0.44 1.62 0.16
11-12 yo 1.06 0.86 1.54 0.22
13-14 yo 0.73 0.49 1.47 0.41
Slider 9-10 yo 1.57 0.39 1.14 0.79
11-12 yo 0.74 0.61 3.38 0.02
13-14 yo 3.49 <0.01 1.80 0.17