Associates of Physical Function and Pain in Patients with Patellofemoral Pain Syndrome

Abstract

Piva SR, Fitzgerald GK, Irrgang JJ, Fritz JM, Wisniewski S, McGinty GT, Childs JD, Domenech MA, Jones S, Delitto A. Associates of physical function and pain in patients with patellofemoral pain syndrome.

Objectives

To explore whether impairment of muscle strength, soft tissue length, movement control, postural and biomechanic alterations, and psychologic factors are associated with physical function and pain in patients with patellofemoral pain syndrome (PFPS).

Design

Cross-sectional study.

Setting

Rehabilitation outpatient.

Participants

Seventy-four patients diagnosed with PFPS.

Interventions

Not applicable.

Main Outcome Measures

Measurements were self-reported function and pain; strength of quadriceps, hip abduction, and hip external rotation; length of hamstrings, quadriceps, plantar flexors, iliotibial band/tensor fasciae latae complex, and lateral retinaculum; foot pronation; Q-angle; tibial torsion; visual observation of quality of movement during a lateral step-down task; anxiety; and fear-avoidance beliefs.

Results

After controlling for age and sex, anxiety and fear-avoidance beliefs about work and physical activity were associated with function, while only fear-avoidance beliefs about work and physical activity were associated with pain.

Conclusions

Psychologic factors were the only associates of function and pain in patients with PFPS. Factors related to physical impairments did not associate to function or pain. Our results should be validated in other samples of patients with PFPS. Further studies should determine the role of other psychologic factors, and how they relate to anxiety and fear-avoidance beliefs in these patients.

Key words: Anxiety, Fear, Pain, Patella, Quality of life, Rehabilitation

List of Abbreviations: FABQ, Fear-Avoidance Beliefs Questionnaire, FABQ-PA, Fear-Avoidance Beliefs—physical activity, FABQ-W, Fear-Avoidance beliefs—work, ITB/TFL, iliotibial band/tensor fasciae latae, KOOS, knee injury and osteoarthritis outcome score, KOS-ADLS, Knee Outcome Survey–Activity of Daily Living Scale, NPRS, numerical pain rating scale, PFPS, patellofemoral pain syndrome

a Department of Physical Therapy, University of Pittsburgh, Pittsburgh, PA

b Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA

c Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA

d Department of Physical Therapy, University of Utah, Salt Lake City, UT

e Physical Therapy Element of United States Air Force Academy, Colorado Springs, CO

f Doctor Program of Physical Therapy, US Army–Baylor University, Fort Sam Houston, TX

g Department of Rehabilitation Sciences, Texas Tech University Health Science Center, Odessa, TX

h Ramstein Outpatient Physical Medicine Clinic, Ramstein Air Base, Kaiserslautern, Germany

Correspondence to Sara R. Piva, PhD, PT, Dept of Physical Therapy, SHRS, University of Pittsburgh, Room 6035, Forbes Tower, Pittsburgh, PA 15260

Supported by the Clinical Research Grant Program of the Orthopaedic Section of the American Physical Therapy Association, and the Pennsylvania Physical Therapy Association Research Fund.

No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit on the authors or on any organization with which the authors are associated.

Reprints are not available from the author.

PII: S0003-9993(08)01632-8

doi:10.1016/j.apmr.2008.08.214

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