Figures published by Ekstrand et al, (2016) indicate that the incidence of hamstring muscle injury has risen by 4% annually compared with earlier studies from 2001.
The question will inevitably be asked as to why this is so and there are several answers in response; few of which are flattering.
Is rehabilitation failing in the cases of those players who have suffered previous injury? Are we preparing well enough in terms of functional movement training for the demands of the sport in question? Do we really do enough in terms of injury prevention?
For those of us who are fully fit and without previous injury all of the above seem obvious; but it is when that sudden unexpected injury occurs that all these factors come into play and questions are subsequently asked.
In looking for the answers, we really need to make a clear differentiation between first-time hamstring muscle injuries and recurrences of older, previous ones.
In both scenarios, getting the initial diagnosis right is always a good starting point!
Clinical examination together with appropriate medical imaging via magnetic resonance imaging (MRI) or ultrasound scanning (US) has been shown to be the most accurate means of identifying the true extent of an injury (Balius et al., 2014; Koulouris et al., 2007).
Establishing the nature and extent of the injury is also crucial to the management plan.
Soft-tissue muscle injuries have four clear stages of healing; and for this to take place properly the damaged muscle tissue has to pass through all four (Krafts, 2010).
Skipping one stage to move on to another based on non-clinical judgement is a recipe for increasing the potential for injury recurrence.
In physiological terms the healing process begins immediately with the inflammatory stage. This tends to average around 48 hours but can be variable.
The degenerative and vascular phase which follows can often take up to 14 days after injury onset. After this, the proliferative phase during which collagen synthesis takes place can run to 28 days post-injury onset (Fernandez-Jáen et al, 2016).
This is an important stage in the healing process since progress and improvement in terms of functionality and reduced pain will be evident. Based on these two factors, it can be all too easy to try to attempt exercises beyond the injured muscle’s capability.
The fourth and final stage concerns remodelling of the affected tissues. This can actually take anything from to three to six months from the date of the injury being sustained until full healing is complete.
A basic knowledge of the physiology of tissue repair as outlined above is essential if rehabilitation of muscle injuries is to be successful.
Krafts (2010) defined the term ‘repair’ when used in the context of healing of damaged tissue as the restoration of tissue architecture and function after an injury.
It follows, therefore, that both musculoskeletal and biomechanical needs have to be met before a return to play can safely be considered.
Sadly, anecdotal evidence leads us to believe that this is not always the case. In the latter stages of healing, factual or objective-based clinical methods are more likely to be overlooked in favour of subjective reporting.
This is an obvious concern. Those regularly involved with sportspeople will know that numerous players will attempt to return to competition before their injuries have fully healed, and that these scenarios are more commonplace than you would think.
Often such decisions are poorly taken; and made in conjunction with coaches and managers based on a subjective feeling of improvement by the athletes or players in question.
Despite more emphasis being placed today on the diagnostic process of injury management than ever before, this happens regularly at elite level where footballers are allowed to return to play based on how they feel as opposed to the clinical picture,
So whether we are trying to bring people back too quickly from injuries when clearly a combination of clinical examination and diagnostic imaging shows that tissue maturation has yet to fully take place is one potential reason for the increase in hamstring injuries identified by Ekstrand et al, (2016).
On that basis alone, it’s certainly not unreasonable to suggest that hamstring injuries are likely to increase even more unless this problem is addressed.
Clearly, solid clinical judgement should not be substituted for emotion.
Delegates who met in Madrid in 2016 for the Spanish Consensus Statement on the Treatment of Muscle Tears in Sport published clear and concise guidelines for soft-tissue muscle injury.
All were unanimous in their agreement that the only accepted factor in final phase of recovery that would indicate a return to play would be through performing basic sports techniques completely pain-free.
As match-day draws closer, though, players are often tempted to come back too early. This happens at all levels and injuries don’t tend to differentiate between elite sports and local competition.
It falls to medical professionals everywhere not only to provide the appropriate injury management advice but also to justify the evidence supporting the advice given.
However, for every high profile footballer who comes off the field with a recurrent injury there are likely to be hundreds of other players outwith the professional leagues or on the public parks who will suffer the same fate.
Since many recreational athletes don’t have the benefit of medical advice or physiotherapy input to assist with their injury management, and particularly with regards to when it safe to return to play, this could well be where the real problem lies.
Further research is therefore required addressing return to play assessments and differentiating between new and recurrent injuries.
Giving solid advice backed up by medical facts could well be the difference between seeing an increase in recurrent injuries and / or better management of new ones.
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