Relationship between dynamic knee valgus with hip and trunk strength in patients with and without patellofemoral pain syndrome

Author(s)

Gabriel Peixoto Leão Almeida

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Faculdade de Medicina (FM/SBD)
• Defense date: 2013-08-26

Examining board members

Amelia Pasqual Marques; Cristina Maria Nunes Cabral; Raquel Aparecida Casarotto

• Advisor: Amelia Pasqual Marques

Abstract

Introduction: The Patellofemoral Pain Syndrome (PFPS) is characterized by anterior knee pain, most commonly in the medial patellar facet. Reduced hip-stabilizers strength and dynamic control of lower limb might be related to the development of the PFPS. Objectives: The primary objective was to compare the Frontal Plane Projection Angle (FPPA) of the knee and hip and trunk strength in women with and without PFPS. The secondary objective was to analyze the relationship between FPPA with hip and trunk strength. Methods: The sample consisted of 43 women divided into two groups: Patellofemoral Group (PFG, n = 22) e Control Group (CG, n = 21). Muscle strength for hip-abduction, hip- extension, hip external- rotation extensors and lateral trunk-flexion (Core lateral) were measured bilaterally using a handheld dynamometer. The limb symmetry index (LSI) was calculated for all subjects. Hip posterolateral complex was calculated as the sum of the three hip muscles assessed divided by three. The FPPA was recorded by a digital camera during step down in three outcomes: a) Initial: before starting the movement; b) Final: in the end of the step down; and c) Final-Initial: difference between the final and initial angles. For FPPA analysis was used the Postural Assessment Software (PAS/SAPo). Results: FPPA Final and Final-Initial for the PFG reveal 5.2º greater than the CG (P < .05). Regarding the hip muscle strength, women with PFPS demonstrated deficit compared to the control group for hip abduction (10.4 ± 3.3 vs 12.7 ± 2.7, P = .02), hip extension (14.2 ± 7.1 vs 18.9 ± 5.9, P = .02), hip external rotation (11.6 ± 3.1 vs 13.5 ± 2.4, P = .03) and hip posterolateral complex (12.1 ± 3.8 vs 15.1 ± 2.8, P = .01). LSI values in women with PFPS were significantly worse than the control group. The hip and trunk asymmetry ranged from 13.1 to 22.6% in the PFG and 1.8 to 3.3% in the CG (P < .05). In the PFG, the hip-abduction and hip posterolateral complex strength showed moderate negative correlation with FPPA Final-Initial (r = -.4). In the CG, the LSI hip-abduction, hip-abduction and hip posterolateral complex strength showed moderate negative correlation with FPPA Final e Final-Initial (r > -.4). In addition, the hip-abduction strength deficit was associated with increased FPPA Final-Initial (r = -.42). Conclusion: The results indicate that women with patellofemoral pain demonstrate increased FPPA of the knee, weakness in hip-abduction, hip- extension, hip external- rotation, extensors and hip posterolateral complex. Women with patellofemoral showed most asymmetry of the hip and trunk muscle strength. The hip weakness, mainly hip external- rotation and posterolateral complex, is associated with increased FPPA of the knee (AU)

• FAPESP's process: 12/10768-0 - RELATION OF DYNAMIC VALGUS OF KNEE WITH HIP AND TRUNK MUSCLE STRENGTH IN PATIENTS WITH PATELLOFEMORAL SYNDROME
• Grantee: Gabriel Peixoto Leão Almeida
• Support Opportunities: Scholarships in Brazil - Master