Very few people who play sport can escape injury and our aim as medical professionals is to ensure that these are properly diagnosed, treated and advice given on when it is safe to return to full activity. This decision on ‘return to play’ is not as straightforward as it seems, as many factors have an influence on ensuring this is done to minimise and risk of re-injury.

In professional sport there is often huge pressure to return players back early, especially in high profile competitions like the World Cup. But even for those of us not playing sport at the highest level we need the same type of advice.

The article below highlights some of the two most prominent injuries which occur in football and rugby with some of the criteria professionals use to advise on the safe return to sport.

Return to play after Sports Related Concussion(SRC)

Sports Related Concussion is due to a traumatic brain injury. The trauma can be direct or indirect, due to an impulsive force transmitted to the brain. There may be a loss of consciousness, but this is not essential in making a diagnosis of concussion.  The one question always asked once diagnosed is ‘when will they be back?’.

Diagnosis

Pitch-side assessment varies in different sports. Some allow temporary replacement for players whilst the assessment is made;  other sports allow only on-pitch/in-game assessment.  SRC can be difficult to accurately diagnose in a match setting, there is obviously pressure to get make the right decision.  SRC is not always straight forward to diagnose as it can be an evolving syndrome, with signs and symptoms absent early on, only to become evident as time passes and the match goes on,  necessitating removal of the player from the field.

Of course, once SRC is recognised or even suspected, the player should be removed from the field of play.

It is important, to formally confirm the diagnosis, and a physical examination, followed by SCAT5 and/or the use of an on-line neuropsychological testing system will help achieve this.  Most players will have a baseline assessment in the pre-season period of both these modalities, or at least a SCAT 5, and any post event re-testing is compared with these, aiding the decision of when the player is fit to return to play.

Recovery and Return To Play (RTP)

Most sports concussions will resolve clinically within 10-14 days, but there is emerging evidence that physiological recovery may take longer. What this means in the context of contact sports and the possibility of sustaining further SRC’s for the individual is an area of debate.

It is worthwhile stating at this stage that the child and adolescent player are more susceptible to the effects of SRC, and hence necessitate a longer recovery time and lengthier RTP protocol.

Currently, RTP begins with a period of rest, usually 24-48 hours;  in young athletes and adolescents this will take longer.  The stages then go through gentle aerobic exercise, usually on a bike in the first instance. The next stages involve running then to shadow training drills, minimal contact training, then full contact training.  Bear in mind that young players will need rest from study, so school/college should be consulted to sanction the necessary period of intellectual inactivity.

At each stage, the player should experience no recrudescence of symptoms that might be attributable to SRC.  If there are any symptoms during or after a session, the player ‘goes back’ to the previous step for the next session, and only progresses to the next when symptom free.

Simultaneously, daily SCAT 5 and neuropsychological testing is essential, and should be compared to the baseline examination carried out before the beginning of the competitive season.

Only when there has been a return to physical and neuropsychological  normality, and reviewed by a medical practitioner,  should the player be made available for selection.

As stated above, most SRC’s resolve within 10-14 days.  Should there be any deterioration during the RTP process, or a delay in RTP, an opinion from an SRC multi-disciplinary clinic should be considered.

Hamstring Injury – A Brief Review

Hamstring injuries (HIS) cause the greatest time loss in football. They comprise 12-15% of all injuries but 37% of muscle injuries in football¹.  HSI also recur in 25% of cases with athletes² and HSI tend to occur with fast running and or with stretch type injuries³. Despite much attention and research, the incidence of hamstring injury in football has been increasing at a rate of 4% / year over the last decade⁴ This may be due to the increased running and matchplay demands on  players.

Hamstrings have complex anatomy and function. They are treated as a muscle group, but each of the 3 hamstring muscles has different size, architecture, fibre type proportion and therefor different roles⁵. Running injuries more typically occur in the biceps femoris⁶ and this muscle may be more configured for speed. Semimembransosus is larger and may be more configured for strength⁷ with semitendinosus longer with small muscle to tendon ratio and may have a greater role in elasticity at speed⁸.

The main action of the hamstrings is to flex the knee, but they also function in hip flexion and extension. In running, the hamstrings contract at end swing to “brake” the swing phase in preparation for stance⁹. In stance they assist gluteal muscles drive the hip from flexion to extension – extending the knee as well¹⁰.

The hamstrings must work concentrically, eccentrically and probably isometrically through very long and short lengths and at different speeds. The connective tissue and tendons also work to store and release elastic energy in running cycles¹¹. The neuromuscular function of the muscles is important as they need to contract and coordinate rapidly especially during full speed sprinting.

The main risk factors for hamstring injury include age, previous injury, strength and flexibility. Warm up and training load may also be factors, including the amount of high intensity running¹².

Injuries are classified due to location (muscle/ Musculotendinous junction (MTJ)/tendon) and the degree of tear (grade 1-4)¹³, with lower grade muscle injuries recovering more quickly. Muscle has its own stem cell population (Satellite cells) which activate during injury, however, MTJ and tendon injuries and higher-grade injuries take longer to recover and are prone to recurrence¹⁴.  Complete tendon tears often require surgery to re-establish the continuity of the muscle. Several muscles have internal tendons such as the Biceps Femoris and these internal tendon tears can also be consequential for recovery time and recurrence.¹⁵

Recovering and returning from a hamstring injury

Rehabilitation options initially typically involve PRICE and management of inflammation and bleeding with protected early motion important, progressing to gentle loading activities such as hydrotherapy.

Progression of loading is based on symptoms with graded criteria based progressions from shortened to lengthened contraction exercises and gradual progression to functional tasks and early painfree resumption of running with the muscle well warmed up and protected¹⁶. Pain is a simple and also one of the most effective markers which will help guide safe return to sport.

It is important that full load eccentric, speed, power and stretch shortening capabilities are restored to the muscle before return to sport because the hamstrings will need this during sports tasks of sprinting and cutting^17,18.

References

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16. Mendiguchia J, Martinez-Ruiz E, Edouard P, Morin JB, Martinez-Martinez F, Idoate F, Mendez-Villanueva A. A Multifactorial, Criteria-based Progressive Algorithm for Hamstring Injury Treatment. Medicine and Science in Sports and Exercise 2017;49-7:1482-92.
17. Mendiguchia J, Martinez-Ruiz E, Morin JB, Samozino P, Edouard P, Alcaraz PE, Esparza-Ros F, Mendez-Villanueva A. Effects of hamstring-emphasized neuromuscular training on strength and sprinting mechanics in football players. Scandinavian Journal of Medicine and Science in Sports 2015;25-6:e621-e9.
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