Lower Amplitude of the Hoffmann Reflex in Women With Patellofemoral Pain: Thinking Beyond Proximal, Local, and Distal Factors

Author(s)

Silva, Danilo de Oliveira ^[1] ; Magalhaes, Fernando Henrique ^[2] ; Faria, Nathalie Clara ^[1] ; Pazzinatto, Marcella Ferraz ^[1] ; Ferrari, Deisi ^[3] ; Pappas, Evangelos ^[4] ; de Azevedo, Fabio Micolis ^[1]

Affiliation

^[1] Univ Sao Paulo State, Sch Sci & Technol, Phys Therapy Dept, Presidente Prudente - Brazil

^[2] Univ Sao Paulo, Sch Arts Sci & Humanities, Sao Paulo - Brazil

^[3] Univ Sao Paulo, Sch Engn, Dept Bioengn, Sao Carlos, SP - Brazil

^[4] Univ Sydney, Fac Hlth Sci, Discipline Physiotherapy, Sydney, NSW - Australia

• Document type: Journal article
• Source: ARCHIVES OF PHYSICAL MEDICINE AND REHABILITATION; v. 97, n. 7, p. 1115-1120, JUL 2016.
• Web of Science Citations: 9

Abstract

Objectives: To investigate whether vastus medialis (VM) Hoffmann reflexes (H-reflexes) differ on the basis of the presence or absence of patellofemoral pain (PFP) and to assess the capability of VM H-reflex measurements in accurately discriminating between women with and without PFP. Design: Cross-sectional study. Setting: Laboratory of biomechanics and motor control. Participants: Women (N=30) aged 18 to 35 years were recruited, consisting of 2 groups: women with PFP (n=15) and asymptomatic controls (n=15). Interventions: Not applicable. Main Outcome Measures: Maximum evoked responses were obtained by electrical stimulation applied to the femoral nerve, and peak-to-peak amplitudes of maximal Hoffmann reflex (Hmax) and maximal motor wave (Mmax) ratios were calculated. Independent samples t tests were performed to identify differences between groups, and a receiver operating characteristic curve was constructed to assess the discriminatory capability of VM H-reflex measurements. Results: VM Hmax/Mmax ratios were significantly lower in participants with PFP than in pain-free participants (P=.007). In addition, the VM Hmax/Mmax ratios presented large and balanced discriminatory capability values (sensitivity, 73%; specificity, 67%). Conclusions: This study is the first to show that VM H-reflexes are lower in women with PFP than in asymptomatic controls. Therefore, increasing the excitation of the spinal cord in PFP participants may be essential to maintaining the gains acquired during the rehabilitation programs. (C) 2016 by the American Congress of Rehabilitation Medicine (AU)

• FAPESP's process: 14/24939-7 - Biomechanical analysis of integrated parameters for diagnosis and classification of women with patellofemoral pain syndrome: study of reliability, precision, diagnostic accuracy and association with pain and function
• Grantee: Fábio Mícolis de Azevedo
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/10755-9 - COMPARATIVE ANALYSIS OF MODULATION OF THE VASTUS MEDIALIS H-REFLEX IN NORMAL AND PATELLOFEMORAL PAIN SYNDROME WOMEN
• Grantee: Nathalie Clara Souto Faria
• Support Opportunities: Scholarships in Brazil - Master