Hamstring problems are a complex issue, and damage to the hamstring tendon, belly, or insertion of the muscle can originate from a multitude of sources. However, in my experience working on this commonly strained area, many times the injury arises from some of the following common factors. This is by no means a comprehensive or complete analysis, but rather is meant as an attempt to shed light on possible causes and a general process to affect change if injured.

1. Low back: I don’t often see a hamstring injury without corresponding low back tightness, injury, degenerative change, etc. If the low back musculature is dysfunctional, there can be resulting compression upon the nerves that relate down along the sciatic nerve through the glute into the hamstrings. This compression on the nerves as they exit the lumbar spine can sometimes dampen the ability of the musculature to contract fully.  Also, as Frans Bosch notes in Running, the erector spinae and thoracolumbar fascia should stabilize the pelvis as the hamstring contracts, if they are either not allowing for pelvic stability, or holding the pelvis in poor alignment, then the hamstring may be at risk.

2. Antagonists: Oftentimes we also see with hamstring problems a corresponding problem with the quadriceps or the hip flexor. So in this scenario the antagonist muscle group, (either of these two, in this example we’ll say the quadriceps), becomes very tight and doesn’t contract uniformly as a result of the tension and the fibrosis (scar tissue) that develops in the muscle tissue of the quadriceps. This lack of contraction in a timely manner in the quadriceps means that the firing pattern in the hamstring is also disturbed. They have to work in unison as the leg goes through its gait cycle, especially to push off. This disturbance in the gait cycle and the firing pattern of the thigh muscles means the hamstring can now be at risk.

3. Pelvic alignment/dysfunction: A major risk factor, especially when speaking of the distal (lower) part of the hamstring, would be anterior rotation of the pelvis. In this case the ilium, the lateral hip bone, is fixed and rotated forward, pulling the origin site of the hamstring farther away from its insertion upon the knee. This usually tends to increase stress distally through the posterior thigh, causing that part of the hamstring to be under greater strain. There are many different presentations and pelvic faults, but a failure to address this or assess it with hamstring issues is negligent.

4. Adductor group: A fourth possible reason for damage to the hamstring would be overuse of the adductor group, especially that of the adductor magnus. The adductor magnus lies deep next to the medial hamstrings and sometimes scar tissue and fascial cross-linkages form between the adductor and the hamstring, which makes the whole chain function less effectively.  Mechanically, there needs to be slide between these two major muscle groups during movement of the leg. As the femur goes through flexion and extension in the gait cycle, this catching and anchoring between the two muscle groups sometimes causes a hitch and then ultimately tearing in the fibers. Because the adductor magnus has a huge cross sectional area and does help the hamstrings with hip extension, it’s very important to treat this both preventatively and also post injury.

This all boils down to the idea that if you are concerned about a hamstring problem or have been susceptible to them, you should get your pelvis, low back, hip flexors, and quadriceps evaluated and treated, and try to diagnose if there’s either any fixation in the pelvis or vertebrae, or excessive muscular tension, fibrosis or damaged muscle tissue in the quadriceps or the hip flexors.

Loading schemes:

The most commonly suggested treatment for hamstring injuries is eccentric loading. It’s very popular based on some studies conducted recently (for example). The use of hamstring eccentric loading undeniably helps, in many cases it's a valuable tool to heal the strain. However, simply doing hamstring loading won’t be enough if the patient or athlete exhibits poor mechanics in their primary sport anyway.  Besides the eccentric component, there should be isometric and reactive training for the injured tissue. There should be drills, strength training and corrective work done to improve those mechanics, proprioception, as well as related tissue imbalances.  Here’s some examples of rehab exercises I would incorporate including eccentric work. The sprint drills come from Dan Pfaff’s sprint drill scheme.

Platelet Rich Plasma Injection:

PRP injections and other sorts of injections for the hamstring are very common now. There’s some research that seems to demonstrate stem cell use with the PRP injection can speed up the healing process, especially at the common tendon origin on the ischial tuberosity. I have seen it go several ways and some athletes I have worked with seemed to respond very well to PRP.  One top Olympic athlete was able to resume training with the doctor’s approval only 8 days after a low volume injection.  For others, it was an expensive experiment which seemed to be less effective than manual therapy and strengthening. Your budget, timeline, and return to competition needs will likely inform this decision.

Manual therapy:

There is little doubt that comprehensive treatment for a tough injury requires a thorough approach. Another important aspect of treating hamstring injuries especially whether chronic or acute is doing specific soft tissue manipulation and sometimes chiropractic manipulation for the lumbar spine and pelvis. Certainly ART, myofascial work, and other forms of soft tissue manipulation need to be done on the ligamentous attachments where the hamstring originates and then also through the region where there has been damage and tearing with the appropriate timelines in mind.

Finally, an overall strengthening program that creates more symmetry and balance throughout the hips, pelvis, and lumbar regions is paramount for long term health and prevention of future hamstring injuries.

If you have questions or would like help diagnosing a hamstring injury please seek out a local ART provider, chiropractic physician, or physical therapist that can help you with diagnosing your specific pathology.