What key criteria should be met prior to returning from a hamstring injury? Expert consensus

Research reviewed: Return to play criteria after hamstring muscle injury in professional football: a Delphi consensus study (Zambaldi et al, BJSM 2017)

Hamstring muscle injuries (HMI) are one of the most prevalent muscular injuries, especially for elite and professional athletes. To make matters worse, there’s research indicating nearly 30% of athlete returning from a hamstring tear suffer re-injury within the first two weeks.

From a sports medicine perspective, the question naturally becomes: What are the appropriate indicators and return to play criteria to reduce re-injury risk and safely return to sport?

Today’s paper sought to answer that question by reaching out to medical experts in the world of professional football (soccer).

The methods

The researchers used a method called the Delphi method which is a multistage process to achieve expert consensus on a subject. In this case, the researchers reached out to all professional football (soccer) club in England to participate and 20 clubs (n=20) represented by a member of their medical staff participated.

The process included three rounds:

• In round 1, participants submitted a list of criteria used for return to play (RTP) after hamstring muscle injury (HMI)

• In round 2, participant rated their agreement for each RTP criterion.

• In round 3, participants re-rated their agreement for each RTP criterion which had reached consensus in the previous round.

Key takeaways

The criteria were grouped into five overlying categories and within those categories, the following individual criteria reached greater than 90% consensus in round 3:

Functional performance:

• Perform maximal sprints

• Achieve maximal linear speed

• Complete at least one football-specific field testing session at maximal performance and under fatigue conditions

• Perform a progressive running plan with running performance eventually matching preinjury levels

• Reach GPS-based targets of external load, based on player-specific or position-specific match markers, which include number of sprints, accelerations, decelerations, changes of direction, maximal speed, high-speed running distance

• Recovery of full aerobic and anaerobic fitness performance

• Complete at least two full trainings with the team prior to be available for match selection

• Good lumbopelvic motor control

Strength:

• Full hamstring muscle strength as compared with the uninjured side and/or to preinjury benchmark values

Flexibility:

• Full muscle flexibility, equal to the uninjured side and/or to preinjury benchmark values

Pain:

• No pain in the muscle

Player’s confidence:

• Player’s self-reported feeling of confidence and readiness to RTP

The extent and variety of the consensus criteria speaks directly to the sensitivity and difficulty in managing return to play after hamstring injuries. Overall, this list of criteria provides a practical foundation and reference point (although certainly not all inclusive) for clearing athletes to return to play following hamstring injuries, with further research needed to continually validate, add, and exclude criteria.