Women with patellofemoral pain syndrome have quadriceps femoris volume and strength deficiency

Abstract

decreased torque, total volume, and CSA of the quadriceps muscle are presented in unilateral with PFPS although cause or effect cannot be established. Large prospective longitudinal studies are needed to detect the changes in the muscle structure and to establish whether these features are a cause of PFPS.

Does Quadriceps Atrophy Exist in Individuals With Patellofemoral Pain? A Systematic Literature Review With Meta-analysis

“…Of these, 2 were randomized controlled trials 11,41 and 8 were cross-sectional studies (TABLE 3). 1,10,20,22,26,29,32,40 The primary aim of 5 studies was to assess quadriceps muscle size. 10,22,26,29,40 The remaining studies measured quadriceps muscle size as anthropometric data or as a secondary measurement of impairment associated with PFP.…”

“…1,10,20,22,26,29,32,40 The primary aim of 5 studies was to assess quadriceps muscle size. 10,22,26,29,40 The remaining studies measured quadriceps muscle size as anthropometric data or as a secondary measurement of impairment associated with PFP. 1,11,20,32,41 The data from 7 studies were included in meta-analyses, as they reported the mean and standard deviation of the size of the quadriceps musculature.…”

“…1,11,20,32,41 The data from 7 studies were included in meta-analyses, as they reported the mean and standard deviation of the size of the quadriceps musculature. 10,20,22,26,29,40,41 Two studies reported the proportion of participants with quadriceps atrophy, 1,32 and therefore were not included in the meta-analyses. One further study was not included in the meta-analyses because this study required quadriceps atrophy for a diagnosis of PFP 11 and selecting a subgroup of patients with PFP based on quadriceps atrophy as a criterion for diagnosis might introduce bias.…”

“…Of the 7 studies that reported mean muscle size, quadriceps muscle size was compared to the asymptomatic limb in 2 studies, 22,29 to a separate comparison group in 4 studies, 20,26,40,41 and to both in 1 study. 10 In terms of the size of individual quadriceps muscles, the size of the VMO was analyzed in 2 studies, with 1 measuring the size of both the VMO and VL 40 and the other measuring only the VMO.…”

How Can We Strengthen the Quadriceps Femoris in Patients with Patellofemoral Pain Syndrome?

“…Generalized quadriceps muscle weakness may result in malposition of the patella (5,6), and altered timing of the VMO muscle activity may mean that the muscle will be at different lengths at contraction initiation, which will affect the muscle's ability to produce force (7). Besides decreased muscle strength of the quadriceps, decreased cross sectional area and total volume of the quadriceps muscle, atrophy of the VMO have been shown in the literature (8)(9)(10). Conservative interventions of PFPS include patient education (11), mobility interventions and exercises for the soft tissue (passive stabilizers of the knee) and muscles (active stabilizers of the knee) around of the knee (12), strengthening exercises for quadriceps muscle (13), muscle training exercises for VMO and VL (14), patellar correction techniques such as taping and bracing (12), electrical stimulation to facilitate quadriceps femoris muscle -especially for the VMO and VL (15), modalities such as cold application for reducing both pain and edema (16).…”