Hip and knee muscle function following aerobic exercise in individuals with patellofemoral pain syndrome

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Abstract

Patellofemoral pain syndrome (PFPS) is a commonly experienced knee disorder that can result in altered muscle activation of the surrounding musculature. There is little evidence on effects of aerobic exercise on quadriceps torque and EMG activation of the vastus medialis obliquus (VMO), vastus lateralis (VL), and gluteus medius (GM). In this study 20 healthy individuals and 20 patients with PFPS had measures of torque and muscle activation taken following aerobic exercise. A modified Balke–Ware protocol was used for the exercise intervention. Baseline and post-aerobic measurements of knee extension torque and VMO, VL, and GM activation during a single leg anterior reaching task. These measurements were only taken on the injured limb. Following exercise, knee extension torque was lower in PFPS patients when compared to controls (p = 0.03). Patients reporting no pain after exercise experienced decreases (p = 0.021) in GM activation following exercise. There was a decrease in VMO (p = 0.010) and VL (p = 0.021) activation in PFPS patients with elevated knee pain. Recreationally active individuals with PFPS may experience different responses in the quadriceps and GM after exercise. Responses may be confounded by whether or not pain is exacerbated by exercise.

Introduction

Patellofemoral pain syndrome (PFPS) is one of the most commonly experienced knee disorders seen in sports medicine (Biedert and Sanchis-Alfonso, 2002, Fulkerson, 2002). PFPS is described as anterior or retropatellar pain in the absence of other specific pathologies (Crossley et al., 2001) and is more prevalent in younger populations, with females being more affected than males (Fulkerson, 1983, Boling et al., 2009). Individuals with PFPS commonly experience recurrent episodes (Biedert and Sanchis-Alfonso, 2002) which may be exacerbated with functional activities such as stair descent and ascent, squatting, kneeling, and prolonged sitting (Powers et al., 2003, Bolgla et al., 2008).

One of the possible neuromuscular factors that predispose an individual to PFPS is weakness of the gluteus medius. Patients with PFPS exhibit reduced gluteus medius strength after prolonged exercise (Dierks et al., 2008). Since the primary actions of gluteus medius are hip abduction and external rotation, weakness and fatigue of this muscle may result in greater adduction and femoral internal rotation (Powers, 2003, Dierks et al., 2008). A more valgus positioned knee from the excessive hip adduction places an increased lateral force on the patella due to greater hip adduction and knee valgus (Merchant, 1988, Dierks et al., 2008). This may result in compensatory strategies during exercise to help avoid excessive patellofemoral compressive forces (Willson and Davis, 2008).

Another potential contributing factor to PFPS is abnormal patellar tracking due to an imbalance between vastus medialis obliquus (VMO) and vastus lateralis (VL) activation. The VMO must activate prior to the VL in a 1:1 ratio (Souza and Gross, 1991) in order to balance the VL’s predominantly laterally directed force (Grabiner et al., 1994). Patients with an abnormal VMO:VL ratio are more likely to develop PFPS (Van Tiggelen et al., 2009). A decrease in the ratio, as seen in PFPS patients, is believed to represent a decrease in medial pull of the patella increasing the lateral force (Davlin et al., 1999). Fatigue in PFPS patients has been shown to have an affect on the VMO:VL ratio compared to the healthy population (Callaghan et al., 2001).

In addition to an imbalance between the VMO and VL, it has also been reported that individuals with PFPS have weaker knee extensors when compared to healthy controls (Callaghan and Oldham, 2004). Currently there is little evidence on the effects of aerobic exercise on quadriceps force and activation of the VMO, VL, and gluteus medius in individuals who are suffering from PFPS. Therefore, the purpose of this study was to compare activation of the VMO, VL, gluteus medius and knee extension torque following an aerobic exercise protocol between individuals with PFPS and healthy controls. We hypothesized that individuals with PFPS would experience decreases in knee extension torque and decreases in VMO and VL activation during a dynamic task following aerobic exercise.

Section snippets

Patients

Twenty healthy patients (age = 22.60 ± 3.62 years, height = 168.21 ± 6.63 cm, mass = 65.50 ± 7.23 kg) and twenty patellofemoral pain syndrome patients (age = 20.90 ± 1.77 years, height = 170.69 ± 6.72 cm, mass = 70.34 ± 7.88 kg, BMI = 23.9 ± 1.8) were recruited to participate in this study (see Table 1 for demographics). All patients were between the ages of 18–45 years and had a body mass index under 40. An inclusion and exclusion questionnaire, general lower extremity health history questionnaire and Kujala questionnaire (

Knee extension torque

We observed a significant group × time interaction for knee extension torque (F1,37 = 5.0, p = 0.03). Post hoc analysis indicated that baseline knee extension torque was significantly lower in PFPS patients after exercise (t1,37 = 2.6, p = 0.01) but not at baseline (p = 0.20). In our exploratory subgroup analysis, we observed a significant difference between subgroups (F2,36 = 3.7, p = 0.03) in knee extension torque after exercise. No significant differences were observed between the groups at baseline (F1,37 = 

Discussion

In the current study, we had patients with and without PFPS perform an aerobic exercise and hypothesized it would cause a decrease in knee extension torque and quadriceps activation and an increase in gluteus medius activation in PFPS patients when compared to healthy controls. When PFPS patients were categorized according to change in pain, different muscle responses were observed for the gluteus medius, VMO and VL, during the single leg anterior reaching task. In patients who reported greater

Conclusion

Recreationally active individuals with PFPS may experience different responses in the quadriceps and gluteus medius after exercise. This response may be confounded by whether or not pain is exacerbated by the exercise. Clinicians should consider the gluteus medius muscle as a potential source of altered neuromuscular function of the quadriceps muscles during exercise in patients with PFPS.

Brittany Ott MEd, LAT, ATC received a BS in Athletic Training as well as a BS in Secondary Education with a concentration in Biology from the University of Nevada-Las Vegas (2008) and a MEd in Athletic Training from the University of Virginia (2010). She is currently working at Mars Hill College as an Assistant Athletic Trainer primarily with women’s soccer and baseball. She also works as the Recruitment and Retention Coordinator for their Athletic Training Education Program.

References (36)

  • M. Boling et al.

    Gender differences in the incidence and prevalence of patellofemoral pain syndrome

    Scand J Med Sci Sports

    (2009)
  • T.J. Brindle et al.

    Electromyographic changes in the gluteus medius during stair ascent and descent in subjects with anterior knee pain

    Knee Surg Sports Traumatol Arthrosc

    (2003)
  • M. Callaghan et al.

    Quadriceps atrophy: to what extent does it exist in patellofemoral pain syndrome?

    Br J Sports Med

    (2004)
  • J. Cohen

    Statistical power analysis for the behavioral sciences

    (1988)
  • S.M. Cowan et al.

    Altered hip and trunk muscle function in individuals with patellofemoral pain

    Br J Sports Med

    (2009)
  • K. Crossley et al.

    A systematic review of physical interventions for patellofemoral pain syndrome

    Clin J Sport Med

    (2001)
  • C.D. Davlin et al.

    The effect of hip position and electromyographic biofeedback training on the vastus medialis oblique:vastus lateralis ratio

    J Athl Train

    (1999)
  • T.A. Dierks et al.

    Proximal and distal influences on hip and knee kinematics in runners with patellofemoral pain during a prolonged run

    J Orthop Sports Phys Ther

    (2008)
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    Brittany Ott MEd, LAT, ATC received a BS in Athletic Training as well as a BS in Secondary Education with a concentration in Biology from the University of Nevada-Las Vegas (2008) and a MEd in Athletic Training from the University of Virginia (2010). She is currently working at Mars Hill College as an Assistant Athletic Trainer primarily with women’s soccer and baseball. She also works as the Recruitment and Retention Coordinator for their Athletic Training Education Program.

    Nicole L. Cosby, MA, ATC is a doctoral candidate at the University of Virginia, Curry School of Education, in the Sports Medicine and Athletic Training Program. Her research focus is in the area of mechanical and neurophysiological changes that occur following manual therapy in patients after ankle sprain.

    Terry L. Grindstaff is an Assistant Professor in the Department of Physical Therapy at Creighton University. He earned a Bachelors of Arts in Sports Medicine from Dakota Wesleyan University, a Master of Science in Health and Physical Education from Middle Tennessee State University, a Doctorate of Physical Therapy from Belmont University, and a PhD in Kinesiology from the University of Virginia. His research examines the effects of therapeutic interventions, specifically manual therapy and exercise, on muscle activation, functional movement (gait and balance), and patient self-reported function.

    Joseph M. Hart, PhD, ATC is an assistant professor of orthopaedic research at the University of Virginia, Department of Orthopaedic Surgery. He also has an academic appointment in the Curry School of Education where he teaches and mentors graduate students in the Sports Medicine and Athletic Training Program. Research focus is in the area of neuromuscular consequences of joint injury, in particular neuromuscular factors that contribute to the progression of osteoarthritis following ACL reconstruction and factors that contribute to the low back pain recurrence.

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