Injury Breakdown: Hamstrung

by Abby Sims

The Mets are coming off a celebratory weekend, winning the first Subway Series of the season. However, they still have some work to do to stabilize the starting pitching staff now that Jonathon Niese is out once again with a hamstring problem (and John Maine is on the 15 day DL with what was reported as shoulder weakness). Mets fans probably remember that Niese suffered a complete tear of the proximal (upper) hamstring in August of last year and had surgery to repair the damage. That injury was sustained while covering first base and stretching to receive a throw to (unsuccessfully) attempt to turn a double play. So what happened this time?

Niese, reportedly felt the soreness in his hamstring while fielding a bunt in the third inning on May 16th and was quoted as having said that he felt “a scary, sharp pain” when he resumed pitching immediately afterward. Niese isn’t the only Mets pitcher to have suffered a recent hamstring injury — he shares that distinction with right-hand reliever Ryota Igarashi who was fresh off the DL when he entered the game on Sunday to almost blow the lead in the ninth inning. Not an auspicious return…

What are the hamstrings and what do they do?

The hamstrings are a group of muscles in the back of the thigh that run from the boney prominence at the bottom of the pelvis (the sit bone, or ischial tuberosity) to just below the knee. Two of the three hamstring muscles attach at the inner (medial) tibia and the third (which has two sections, or heads) has multiple attachments, primarily into the outer (lateral) side just below the knee at the fibular head, but also into muscle and ligaments of the outer compartment.

The hamstrings act to bend (flex) the knee and also work to extend the hip (bringing the thigh behind the plane of the hip). However, they do not act as primary movers to do both of these motions simultaneously.

Studies have shown that the hamstrings also act during the last degrees of knee extension (straightening). While the quadriceps (the muscles in the front of the thigh) act to straighten the knee, the hamstrings contract – pulling the tibia backward – to prevent excessive extension (hyperextension). You may recall from a prior blog entry that anterior cruciate ligament (ACL) injuries result from traumatic hyperextension. The hamstrings are recruited to help to prevent ACL tears, providing some level of dynamic stabilization.

During the gait cycle (walking) the hamstrings act to decelerate (slow down) the forward swing of the leg. By doing so they help to control the position of the foot when the heel strikes the ground. If the knee is unable to straighten all the way, possibly because of a contracture of the hamstrings, the foot will strike in more of a flat position, changing the way forces are sent up through the chain of the lower extremity. This could cause undue stress on muscles and joints up through that chain.

Why is hamstring tightness such a big deal?

Tight hamstrings can cause a variety of problems due to the excessive pull of the muscles on their attachments. Poor posture and alignment are among the end results. Excessive tightness rotates the pelvis backward, and can cause the spine to be too arched in the low back (lumbar spine) or too rounded in the mid back (thoracic spine). Studies on those with unstable segments in the lumbar spine have found that a significant percentage have particularly tight hamstrings (See Wheeless’ Textbook of Orthopaedics). Tight hamstrings can also alter a person’s gait pattern (the way he or she walks) and influence the way we sit – tight hams prevent sitting with the knees extended unless the back is rounded forward to compensate.

As with other tight muscles, lack of hamstring flexibility prevents the muscles from acting as efficiently to absorb shock, thereby transmitting more force to the joints and predisposing to injury. In addition, sports that require significant hamstring flexibility will likely lead to traumatic strains if the limit of stretch of the muscle is exceeded during play. Remember, a muscle strain comes in three basic varieties, the most involved of which (Grade III) is actually a complete tear; that is what Jonathon Niese wanted to prevent this time around

Can hamstring strains be prevented?

Stretching in order to improve flexibility and warming up to prior to doing so can be very helpful in minimizing the risk of hamstring strains. Sufficient strength and endurance of the muscles, both as hip extenders (with the knee straight) and as knee flexors is important to prevent injury. Much has also been said about the need to train the muscles both concentrically (contracting/shortening against resistance) and eccentrically (lengthening contractions that occur with the resisted release of a contraction). Working creatively to include various methods of hamstring strengthening can be instrumental to preventing injury. It seems likely that the Mets medical, athletic training and strength & conditioning staff have incorporated all of these into the prevention program that the players have followed.

So, why do they seem to suffer so many injuries? Genetics have to be factored in, as does the freaky nature of some plays that push a muscle to (or beyond) its limit. Keep in mind however, that while some players readily sacrifice their bodies to make the out, there are those who protect themselves first, even at the expense of hearing a rousing chorus of boos. These players minimize their personal risk while letting an opponent advance a base or score a run. In the short term that might not appear to be the “team first” approach the fans are looking for. However, keep in mind that because he put the play first and himself second, future Hall of Famer Ken Griffey Jr. lost a cumulative total of about four years playing time while in his prime. That would have translated into a lot more wins and record-setting stats. Maybe we should lighten up and look at the bigger picture once in awhile.

Abby Sims is an orthopedic and sports physical therapist who has been in private practice in NYC for the past 30 years (you may be familiar with her husband, sportscaster & WFAN alum Dave Sims). Abby has a Masters of Science in Physical Therapy from Duke University and has extensive experience working with professional, collegiate and recreational athletes with musculoskeletal injuries – both non-operative and operative. She has also enjoyed lecturing at many medical conferences. Abby looks forward to responding to your questions or writing about topics that you suggest. For more information about Abby, or her practice, please check out www.RecoveryPT.com as well as www.AthletiSense.com.