Research Review By Kevin Neeld©

Date Posted:

July 2009

Study Title:

Hip joint range of motion restriction precedes athletic chronic groin injury

Authors:

Verrall GM et al.

Author's Affiliations:

SPORTSMED. SA Sports Medicine Clinic, Adelaide, Australia; Department of Medical Imaging, Flinders Medical Centre, Adelaide Australia, School of Nursing, University of South Australia, Adelaide, Australia

Publication Information:

Journal of Science and Medicine in Sports 2007; 10: 463-466.

Background Information:

Restrictions of hip joint range of motion (ROM) have been previously associated with various hip related injuries. As examples, a decrease in total hip joint ROM is often present in athletes with osteitis pubis and pubic bone stress injuries; and a decrease in hip abduction ROM is related to adductor injury. Due to limitations in previous work, it is not possible to determine if hip joint ROM restrictions precede, occur concomitantly with, or follow chronic groin injury (CGI).

The aim of this prospective cohort laboratory study was to determine if hip stiffness preceded the development of sports-related chronic groin injury in elite Australian rules football players.

Pertinent Results:

  • 29 male athletes were studied, 4 of whom developed CGI.
  • No significant differences were noted between dominant and non-dominant legs for internal and external rotation ROM.
  • Having a lower body weight (p=0.02) and a decreased total hip ROM (p=0.03) were the largest risk factors for developing CGI.
  • Athletes sustaining a chronic groin injury had an average body weight of 72.50 kg and total hip rotation ROM of 83.13°. Athletes not sustaining a chronic groin injury had an average body weight of 84.92 kg and total hip rotation ROM of 103.18°.

Clinical Application & Conclusions:

The primary finding of this study is that restriction in total hip joint rotation ROM preceded chronic groin injury in a population of Australian rules football players. This risk factor was statistically significant, even after accounting for a lower body weight.

Clinicians and coaches can help minimize chronic groin injury risk of their athletes by assessing hip joint ROM and addressing deficiencies. Although subject to a wide range of variability depending on individual hip joint anatomy, in general athletes should have around 30-40° of internal rotation ROM and 40-60° of external rotation ROM. Range of motion deficiencies can be remedied by addressing local soft-tissue structures using a foam roller and/or lacrosse ball and by using a variety of stretches.

Various manual therapy techniques could be employed if you work in a multi-disciplinary environment, and have access to a chiropractor or physiotherapist for your clients. To improve internal rotation ROM, athletes can perform a supine lying knee-to-knee stretch, a prone flexed knee internal rotation stretch, and supine knee to opposite shoulder stretch. To improve external rotation ROM, athletes can perform a seated “newspaper” stretch by sitting with their heel across their opposite knee and gently pressing on the knee of the raised leg.

Study Methods:

Twenty nine male Australian rules football players (average age 21.4 years, range 18-30) without a history of chronic groin injury participated in the study. A single tester used a goniometer to assess each athlete’s hip internal and external rotation ROM while supine with the hip and knee in 90° of flexion.

Athletes were tracked for two playing seasons (18 months from baseline) for the presence of chronic groin injury. Chronic groin injury was defined by groin pain lasting at least 6 weeks that caused the athlete to miss at least one competition. Total hip ROM was quantified by adding the internal and external rotation ROMs from both legs.

Study Strengths / Weaknesses:

The study had a few notable weaknesses:
  • The participant population was relatively small and included only male Australian rules football players. This limits the external validity of this study. It is unclear at this point if the results from this study can be applied to athletes from different sports and female athletes.
  • Hip joint ROM was assessed using a single measurement and only with the hip and knee flexed to 90°. Due to the variation in hip joint movement and ROM differences when the hip is flexed 90° compared to fully extended, multiple measurements in both the flexed and extended position could alter the current findings.
  • Lastly, only hip internal and external ROM was quantified. It is possible that restrictions in hip flexion/extension and abduction/adduction could also influence chronic groin injury risk.

Additional References:

  1. Arnason, A et al. Risk factors for injuries in football. Am J Sports Med, 2004, 32(1S): 5S-16S.
  2. Williams, J. Limitation of hip joint movement as a factor in traumatic osteitis pubis. Br J Sports Med, 1978, 12: 129-133.