1. Interventions for prevention and
rehabilitation of hamstring injuries
Reza Rahimi-Moghaddam
Sports Medicine Association of Gilan
Province, Iran

2. Background
• Hamstring injuries are common
among amateur and professional
athletes
(Sebelien C. et al. 2014; Petersen J. et al. 2005)
• A frustrating injury for the injured
athletes, coaches and clinicians

3. Background
• 12-16% of all injuries in athletes with
a re-injury rate as high as 22-34%
(Naclerio et al. 2013; Schmitt et al. 2012; Mendiguchia et al.
2012; Arnason et al. 2008)
• One-third of the injuries will recur
with the greatest risk during the initial
2 weeks following return to sport
(Orchard & Seward, 2002)

4. Mechanism of Injury

5. Mechanism of Injury
• Most often injuries occur during maximal sprints
(Arnason, et al. 2008; Bahr, 2013)
• The majority of injuries involve biceps femoris
(Warren et al. 2010; Zorić, 2012; Opar et al. 2012)
• The higher the activation level of a muscle during
eccentric contraction, the more mechanical
energy the muscle would absorb before a muscle
strain injury occurs
(Liu et al. 2012)

6. Mechanism of Injury
• Biceps femoris is under greater strain during late swing phase.
(http://running.competitor.com/2014/03/photos/best-ways-treat-hamstring-
injuries_97314#lD1dATSZipXIAlpm.99)
• The hamstrings must change from functioning eccentrically, to
decelerate knee extension in the late swing, to concentrically
(Petersen & Hölmich, 2005; Sherry et al. 2011)

7. Hamstring Injury Classification
• Traditional Grading System
(Petersen & Hölmich, 2005; Goldman & Jones, 2010; Heiderscheit et al.
2010; Mendiguchia et al. 2012; Opar et al. 2012)
• Modified Peetrons Classification
(Hamilton et al. 2013; Ekstrand et al. 2012 & 2013; Mueller-Wohlfahrt et
al. 2012)
• MRI or Ultrasound Categorization
(Chan et al. 2012; Ekstrand et al. 2013)
• British Athletics Medical Grading
System
(Pollock et al. 2014)

8. Hamstring Injury Classification
• Clinicians and coaches use traditional
simple grading system widely
• In a preventive program, use of
traditional grading system is
insufficient
• The bottom line is always to offer the
injured athlete the best strategies to
reach a complete and safe recovery

9. Risk Factors
• Nonmodifiable
- Risk factor can not be changed
• Modifiable
- Risk factors can be changed
(Bahr et al. 2003; Petersen & Hölmich 2005;
Gambetta, 2006; Heiderscheit et al. 2010; Liu et al.
2012; Brukner et al. 2013; Sebelien et al. 2014)

10. Risk Factors
• Other Factors:
- Psychological factors
(Hoskins & Pollard, 2005)
- High number of type II fibers
(Garrett et al, 1984; Lieber & Fride´n, 1988; Woods et al. 2004)
- Poor level of aerobic fitness
(Porter & Rushton, 2003; Giacchino & Stesina, 2013)

11. Prevention
• No perfect way to completely avoid
hamstring injuries
• The risks can be minimized by paying
attention to the principles of preventive
program
• Complete rehabilitation of injuries
before return to play is important, but
primary prevention of initial hamstring
injuries is even more important
(Woods et al. 2004)

12. Prevention
• Reducing the risk of post rehabilitation
re-injury
• Use of exercise interventions such as
stretching and strengthening exercises to
reduce the risk of injury to athletes
(Porter & Rushton, 2015)
• Eccentric hamstring strength may be an
important protective factor
(Mjølsnes et al. 2004; Gambetta, 2006; Schache, 2012; Bahr,
2013; Malliaropoulos et al. 2013; Opar et al. 2014; Porter and
Rushton, 2015 )

13. Prevention
• Duration of 10-12 weeks, 2-3 sessions
per week for eccentric strengthening
during preseason program
(Askling et al. 2003; Petersen et al. 2011; Cowell et al. 2012)
• Nordic hamstring exercise, an
intervention targeting the prevention and
rehabilitation of hamstring injuries
• It has been shown to reduce the risk of
hamstring injuries
(Arnason et al. 2004; Brooks et al. 2006; Melegati et al. 2013;
Sebelien et al. 2014;)

14. Prevention
Starting position End positionMid position
Nordic Hamstring Exercise

15. Prevention
• Excessive overload will be placed on
the hamstring
• Uncontrolled performing, no positive
adaptation
(Naclerio & Goss-Sampson, 2013)
• No increase in concentric hamstring
strength
(Mjølsnes et al. 2004; Clark et al. 2005)

16. Prevention
• Combination of eccentric and concentric
specific training protocols would appear
to provide the best potential for reducing
the risk of hamstring injury
(Clark, 2008)
• Hamstring/Quadriceps (H:Q) balance
• Muscle strength imbalances may play a
larger role than strength in isolation

17. Prevention
• H:Q imbalances observed in
footballers who suffered
subsequent hamstring strain
(Prior et al. 2009)
• Performing preseason isokinetic
assessments in professional soccer
teams is needed
(Croisier et al. 2008)

18. Prevention
• Stretching exercises for prevention
and management of hamstring
muscle injuries
• Optimal level of flexibility that
prevents injury is not clear
(Dadebo et al. 2004)

19. Prevention
• No clinical significant differences
between hamstring flexibility and
injury rates
• Nothing in the literature to support
hamstring injuries are due to a lack of
stretching
(Roils & George2004; Arnason et al. 2008; Goldman &
Jones2010; Brukner et al. 2013; Rogan et al. 2013 )

20. Prevention
• Conflicting and insufficient evidence
regarding the need to increase
hamstring flexibility using pre-exercise
hamstring stretching
• Tooley (2009): pre-exercise stretching
may not reduce hamstring injury
• Chan et al. (2012): pre-exercise
stretching is beneficial and helps to
prevent hamstring strains

21. Prevention
• Type of stretching, time and frequency
of stretching exercise are still a matter
of conflict
(Malliaropoulos et al. 2004; Arnason et al. 2008; Marques et al.
2009; Fasen et al. 2009; Chan et al. 2012; Brukner et al. 2013;
Tomruk et al. 2014)
• Further investigations are required,
evaluating the effectiveness, frequency,
duration and type of stretching of
hamstring muscles

22. Rehabilitation
• The primary objectives of a
rehabilitation program:
- Returning the athlete to sport at prior
level of performance
- Restoration of function to the greatest
possible degree in the shortest possible
time with a minimal risk of injury
recurrence
(Petersen & Hölmich, 2005; Heiderscheit et al. 2010;
Hamilton, 2012)

23. Rehabilitation
• Concentrate on one of the main
problems, the extremely high tendency
of hamstring injury to become recurrent
(Croisier, 2004; Engebretsen et al. 2010; Thorborg, 2012)
• Early return to play, incomplete and
aggressive rehabilitation increases the
risk of re-injury in the early stage after
returning to sport
(Woods et al. 2004; Croisier, 2004; Croisier et al. 2008;
Engebretsen et al. 2010; Dellal et al. 2013)

24. Rehabilitation
• The first month after return to play is the
highest risk time for recurrence
(Brukner et al. 2013; Swinnen, 2015)
• Extremely difficult to decide when the
athlete is ready to return to sport
(Orchard et al. (2005); Heiderscheit et al. (2010); Dellal et al. 2013)
• Return to sport in 2-3 weeks: still ongoing
muscle regeneration in the presence of
mature scar tissue formation
(Orchard & Seward, 2002; Orchard & Best 2002; Croisier, 2004;
Engebretsen et al. 2010; Sherry et al. 2011)

25. Rehabilitation
• Increased muscle injury severity is
associated with longer times to
return to sport
(Ekstrand et al. 2013)
• Maladaptation may impact on time
to return to competition, and delay
rehabilitation process
(Hoskins & Pollard 2005; Mason et al. 2007; Opar et al.
2012; Fyfe et al. 2013)

26. Rehabilitation
• Rehabilitation also needs to integrate
exercises to promote core stability and
develop muscle strength
(Sherry et al. 2004; Chumanov & Heiderscheit, 2007; Clark,
2008; Mendiguchia & Brughelli, 2011; Brukner et al. 2013;
Melegati et al. 2013)
• Limited evidence to suggest that rate of
recovery can be increased with an
increased daily frequency of hamstring
stretching exercises
(Mason et al. 2007)

27. Rehabilitation
• Flexibility is a known factor in physical
fitness
• To avoid the hamstring muscle
becoming less flexible after the injury,
hamstring stretching can begin in the
third phase of rehabilitation program
(Petersen & Hölmich, 2005)
• Assessment is a must for return to play

28. Rehabilitation
• Little evidence suggesting a valid
functional test to determine return to
play
(Schmitt et al. 2012)
• Rely on subjective measures such as
“pain free movements” is not
sufficient
(Mendiguchia & Brughelli, 2011)

29. Rehabilitation
• Multi-factorial approach to
rehabilitating hamstring injuries is
needed
(Mason et al. 2007; Mendiguchia & Brughelli, 2011;
Seagrave et al. 2014)

30. Summary
• Hamstring strain is a well-documented
problem with a high re-injury rate within
athletes.
• Most injuries often occur during maximal
sprints and often involve biceps femoris.
• There are many risk factors that indicate
the need to develop and improve
prevention strategies for primary and
recurrent injuries of hamstring muscles

31. Summary
• No perfect way to completely avoid
hamstring injuries, but the risks can be
minimized by paying attention to the
principles of preventive program.
• A history of hamstring injury, preseason
assessment, implementing eccentric
exercises specially Nordic Hamstring
Exercise, and considering H:Q balance can
play important roles in prevention program.

32. Summary
• In a prevention program, the effectiveness
of stretching exercise is not clear.
• Type of stretching, time and frequency of
stretching exercise are still a matter of
conflict.

33. Summary
• In a rehabilitation program, the
primary objectives are returning the
athlete to sport at prior level of
performance in the shortest possible
time with a minimal risk of injury
recurrence
• One of the main problems is the
extremely high tendency of
hamstring injury to become recurrent

34. Summary
• The first month after return to play is the
highest risk time for recurrence
• A history of hamstring injury in the
previous 12 months is a predictor of
hamstring injury recurrence.
• Early return to play, incomplete and
aggressive rehabilitation increases the
risk of re-injury in the early stage after
returning to sport

35. Summary
• Severity of the muscle injury, maladaptation,
and poor core stability affect the duration of
the lay-off and making decision.
• Limited evidence about the effect of flexibility
on reducing time to return to play
• However, stretching exercises help the
hamstring muscle becoming less flexible after
the injury.
• Rely on subjective measures such as “pain
free movements” is not sufficient.

36. Summary
• Multi-factorial approach to
rehabilitating hamstring injuries is
needed.
• By creating and implementing a
strategized approach to injury
prevention, more of the athletes time
can be spent competing and training
instead of rehabilitating.

37. THANK YOU FOR
YOUR ATTENTION