Similar to a growing number of athletic facilities across the US, Gallagher Performance places a significant amount of emphasis on assessing our athletes in order to address structural adaptations and movement dysfunctions appropriately during the course of the athlete’s training program. This trend is seen throughout collegiate and professional athletics as organizations are recognizing the importance of keeping their athletes healthy by promoting optimal training environments.
However, this service is rarely available to young athletes prior to sport participation or a training program. This is truly unfortunate since proper screening of athletes is not available when it arguably matters most, during the early stages of athletic development. Dr. Mike O’Donnell DC, CCSP, CSCS touched on this concept in a recent interview. He states,
“In North America, athletes start playing a sport as unprepared youth with no background in general conditioning. This isn’t always true, but we have no system to condition young athletes besides just playing the sport. In an Eastern model, camps are held without a sport focus to condition young athletes, and the specialization comes later. In general, early specialization is a mistake. This has been proven to limit progress, lead to early burnout, and increase injury rate.”
Certainly in an ideal situation, young athletes would be introduced to general conditioning prior to sport participation. Likewise, prior to the initiation of a general conditioning program and/or sport participation, young athletes should be screened to provide an understanding of any structural adaptations that will require individualized considerations to ensure continual progress in the pursuit of achieving athletic mastery and minimize the risk of serious injury.
Structural Adaptations: How Common Are They?There are numerous studies suggesting that the majority of people in the general population, especially athletes, have developed various forms of structural adaptations. What are structural adaptations? Essentially they are alterations in the anatomical structure of the body due to repeated physical stresses placed upon joints and connective tissue. These adaptations often occur during the developmental years. Keep in mind, structural adaptations are not pathological in nature, but certainly require their own unique management strategies since they will impact movement mechanics and potentially be a reason for movement dysfunction. It is also important to understand that not all individuals with structural adaptations will present with symptoms, such as pain. In fact, the majority of them will not present with pain.
Below are just some of the findings from a growing collection of evidence that suggests how frequently structural adaptations may occur:
- 79% of asymptomatic professional baseball pitchers have evidence of shoulder labrum abnormalities on MRI.
- 40% of dominant shoulders in asymptomatic tennis and baseball players had evidence of partial or full-thickness rotator cuff tears on MRI.
- 34% of asymptomatic individuals in the general population had evidence of rotator cuff tears. 54% of those 60 years of age and older had evidence of rotator cuff tears - so if you’re dealing with older adults, you could safely assume they are present in almost half of this population.
- Recent research has demonstrated that high school baseball pitchers from southern, warm weather climates have decreased shoulder internal rotation range of motion and external rotation strength compared to northern, cold weather climate players. This is likely attributed to adaptation from the number of months spent participating in pitching activities during the calendar year.
- 64% of asymptomatic people that underwent an MRI of their lumbar region had abnormal findings. Keep in mind these are individuals with evidence of lumbar disc pathology (i.e. bulge or herniation) who have NO symptoms and NO pain.
- 93% of youth hockey players age 16-19 have evidence of femoroacetabular impingement (FAI) and hip labral tears. FAI is the result of bony overgrowth found at the femoral head and/or acetabulum of the pelvis. FAI has been linked to increased risk of injury for osteitis pubis and sports hernias.
- 77% NCAA D1 and professional hockey players evaluated in one study had abnormal hip/groin MRI despite being asymptomatic. Hockey players are also more likely to have a structural change known in the hip known as hip retroversion, which allows for greater hip external rotation and reduces the degree of hip internal rotation.
- 87% of 125 NFL prospects had findings consistent with FAI on MRI. The only independent predictor of groin pain was the degree of bony overgrowth.
- Evidence suggests that roughly 25% of men in the general population have some degree of FAI despite being asymptomatic.
ConclusionStructural adaptations are clearly a common occurrence both in athletes as well as the general population. The impact these adaptations have on movement cannot and should not be ignored. For example, individuals with FAI will experience varying degrees of limited hip flexion range of motion. This limitation in hip flexion will impact exercises such as squats, lunges, and other considerations in lower body training methods. If this limitation is ignored or missed, it can have potentially serious implications such as the development of labral tears or lumbar disc injury due to compensations in movement through the hips, pelvis and lumbar spine.
The key point to recognize is the presence of such adaptations have their own unique impacts on posture and movement that influence the design and outcomes of both training and treatment plans. Training programs need to take these issues into account, making considerations for differences in gender, age, level of physical preparation, primary sport(s) participation, and injury history. While some structural adaptations can be impacted by corrective strategies, others simply need to be accounted for in exercise selection and movement education in order to avoid causing them to reach symptom threshold.
References- Miniaci et al. Magnetic resonance imaging of the shoulder in asymptomatic professional baseball pitchers. Am J Sports Med. 2002 Jan-Feb;30(1):66-73.
- Connor et al. Magnetic resonance imaging of the asymptomatic shoulder of overhead athletes: a 5-year follow-up study. Am J Sports Med. 2003 Sep-Oct;31(5):724-7.
- Sher et al. Abnormal findings on magnetic resonance images of asymptomatic shoulders. J Bone Joint Surg Am. 1995 Jan;77(1):10-15.
- Jensen et al. Magnetic resonance imaging of the lumbar spine in people without back pain. N Engl J Med. 1994 Jul 14;331(2):69-73.
- Kaplan et al. Comparison of shoulder range of motion, strength, and playing time in uninjured high school baseball pitchers who reside in warm- and cold-weather climates. Am J Sports Med. 2011 Feb;39(2):320-328.
- Birmingham et al. The effect of dynamic femoroacetabular impingement on pubic symphysis motion: a cadaveric study. Am J Sports Med. 2012, 40(5), 1113-1118.
- Philippon et al. Prevalence of increased alpha angles as a measure of cam-type femoroacetabular impingement in youth ice hockey players. Am J Sports Med. 2013, 41(6), 1357-1362.
- Silvis et al. High Prevalence of pelvic and hip magnetic resonance imaging findings in asymptomatic collegiate and professional hockey players. Am J Sports Med. 2011, 39(4), 715-721.
- Larson et al. Increasing alpha angle is predictive of athletic-related “hip” and “groin” pain in collegiate national football league prospects. Arthroscopy. 2013, 29(3), 405-410.
- Hack et al. Prevalence of cam-type femoracetabular impingement morphology in asymptomatic volunteers. J Bone Joint Surg Am. 2010, 92(14), 2436-2444.
