Table 1 Efficacy of hip joint musculature strengthening in subjects with patellofemoral pain syndrome
Mascal et al13Tyler et al38Boling et al41
Type of study2 case reportsCohort studyPre-/post-test intervention study
Groups2 patients with PFPS, exhibiting weak hip abductors, extensors and external rotators1 group—35 PFPS patients, mean (SD) age 35 (16) years (29 women, 6 men) demonstrating hip flexion, abduction and adduction weaknessGroup 1—14 PFPS patients
Group 2—14 control subjects
TreatmentPhysical therapy once or twice weekly for 14 weeks plus HEP. Weeks 0–6 involved non-WB exercises, abdominals and isometric hip exercises. Weeks 6–10 involved WB exercises, isometric and dynamic exercises in single leg stance. Weeks 10–14 involved functional training6 week treatment programme-consisted of OKC and CKC strengthening and flexibility exercises for hip musculature. Hip flexors, abductors, adductors and extensors were progressively strengthened. Stretching in Ober and Thomas test positions as well as self performed stretches6 week progressive weight bearing rehabilitation programme, with emphasis on hip joint abductor and quadriceps strengthening. 3 sessions per week (1 supervised session and 2 self directed sessions)
Outcome measuresFunctional status questionnaire, VAS worst pain, hip and abdominal strength, observational gait analysis, step down task, 3 dimensional kinematics of lower extremityHip flexion, abduction and adduction strength, Thomas and Ober tests, VAS for pain on ADLs as well as on exercise (treatment success defined as a min of 1.5 cm reduction of pain on each VAS)Pain as measured on a VAS. FIQ. VMO and VL EMG onsets. Gluteus medius EMG onset
ResultsSignificant reduction in pain, improved lower extremity kinematics, ability to return to original level of functionHip flexion strength improved by 35%, improvements in hip abduction and adduction strength, increased flexibility, significant decrease in VAS scoresVMO and VL onset timing differences, as well as VAS and FIQ scores improved in group 1 subjects. Post-test scores for group1 were equivalent to those in group 2
  • ADL, activities of daily living; CKC, closed kinetic chain; EMG, electromyogram; FIQ, Functional Index Questionnaire; HEP, home exercise programme; OKC, open kinetic chain; PFPS, patellofemoral pain syndrome; VAS, Visual Analogue Scale; VL, vastus lateralis; VMO, vastus medialis oblique; WB, weight bearing.