Hamstrung?

There is a reason the word hamstring has been colloquialized as a verb. Any injury to your hamstrings can cause serious pain, and be severely disabling as they are used every single day when you’re walking. Fortunately, Excel physical therapists are experts in rehabilitating hamstring injuries. There are two primary types of injuries to the hamstrings: hamstring tendinopathy and hamstring tears, commonly called “pulls” or “strains.”

The hamstrings are composed of three main muscles: the semitendinosus, the semimembranosus, and the biceps femoris – four if counting a portion of the adductor magnus.  The biceps femoris is the muscle most likely to be injured, and one of the more common ways to injure your hamstring is running. In running, strain is most likely to occur in late swing.  In this position, the hamstring is maximally lengthened while still building tension (eccentrically contracting) in order to slow the thigh from advancing too far forward.

Understanding the mechanics that caused injury is crucial before any type of treatment can commence.  Typically, treatment for acute hamstring tears includes a period of rest before beginning gentle range of motion exercises and progressive strengthening.  Most importantly, the team of therapist and patient must uncover – and correct – any faulty movement patterns or strategies in order to mitigate future injuries. Anyone who follows sports knows that an athlete’s “two week hamstring pull” always seems to lead to a two month stint on the injured reserve.

One of the most studied exercises for preventing hamstring strains is the Nordic hamstring curl (NHC, see below figure).  The NHC is – or should be – a staple of all sprinting athletes including soccer players, football players, sprinters, and baseball players. Muscle strength is joint-angle specific, meaning that the angles you train them at will transfer over to activities in those same angles. For sprinting, this means the hamstring should be trained in the same angle in which they are likely to be strained. Luckily, the NHC is performed at the same hip and knee angles where the hamstring is most likely to be injured (late swing phase with the thigh coming forward as the knee extends).

You may be wondering if you should be doing NHCs with the ankle plantarflexed (left) or dorsiflexed (right) since the gastrocnemius, one of the calf muscles) can also act as a knee flexor. Luckily, fifteen volunteers elected to undergo electromyography (EMG) testing during this exercise to determine which position is best, demonstrating no significant difference in EMG activity for neither the medial gastrocnemius nor the biceps femoris.

While both positions are likely useful, the authors note that the dorsiflexed position may confer an advantage in preventing hamstring strains. This advantage being due to the principle of specificity as discussed above, and also due to the fact that the ankle is dorsiflexed (toes up) in late swing (again, where most strains occur).

In addition to strains, proximal hamstring tendinopathy (PHT) is usually caused by overuse. Hamstring tendinopathy is a common complaint of runners of all skill levels. Often, patients will point to the posterior thigh below the buttocks as the source of pain. This location combined with an increase in training volume (and other factors) are classic signs pointing to PHT. While rehabilitating this injury, rest is the key. Throughout care, there is a logical progression of exercises aimed at improving the tendon's ability to accept loads, while also improving the athlete’s movement patterns:

Phase 1 includes isometrics (also great for pain reduction!) and lower load exercises. Pictured are the single leg bridge holds (30-45 sec) and the banded straight leg pull down.



Phase 2 consists of more dynamic exercises. Pictured is the supine leg curl. Take off your shoe so your sock slides across the floor toward your butt. Other Phase 2 exercises include Nordic hamstring curls, or machine leg curls.


Phase 3 includes hamstring activity in more functional movement patterns such as step ups and Romanian deadlifts. Pictured is the single leg deadlift, but another option is hip thrusts.


Phase 4 is the final stage and incorporates return to sport activities. Pictured is the sprinter's leg curl. This is the phase when agility and plyometric drills (bounding and cutting) can be incorporated.

Progression from each phase is determined by pain after exercise. Minimal pain the day after exercise indicates the tendon is ready for additional load. Pain indicates further rest is needed before further strengthening.

All Excel locations have a variety of equipment to help accelerate the rehabilitation process. More importantly, our clinicians know how to effectively examine, evaluate, and prescribe the correct combination of manual therapy, neuromuscular reeducation, and therapeutic exercises to get you back up and running as soon as possible!


References

Dutton M. Orthopaedic Examination, Evaluation, and Intervention, Second Edition. McGraw Hill Professional; 2008.

Heiderscheit BC, Sherry MA, Silder A, Chumanov ES, Thelen DG. Hamstring strain injuries: recommendations for diagnosis, rehabilitation, and injury prevention. J Orthop Sports Phys Ther. 2010;40(2):67-81.

Brukner P. Hamstring injuries: prevention and treatment-an update. Br J Sports Med. 2015;49(19):1241-4.

Ramos GA, Arliani GG, Astur DC, Pochini AC, Ejnisman B, Cohen M. Rehabilitation of hamstring muscle injuries: a literature review. Rev Bras Ortop. 2017;52(1):11-16.

Comfort P, Regan A, Herrington L, Thomas C, McMahon J, Jones P. Lack of Effect of Ankle Position During the Nordic Curl on Muscle Activity of the Biceps Femoris and Medial Gastrocnemius. J Sport Rehabil. 2017;26(3):202-207.