Elena Estébanez-de-Miguel1, Carlos López-de-Celis2, Santos Caudevilla-Polo3, Vanessa González-Rueda2, Elena Bueno-Gracia3, Albert Pérez-Bellmunt4. 1. Department of Physiatrist and Nursery, Faculty of Heath Sciences, University of Zaragoza, Zaragoza, Spain. Electronic address: elesteba@unizar.es. 2. Faculty of Medicine and Health Sciences, Universitat International de Catalunya, Barcelona, Spain; Fundació Institut Universitari per a La Recerca a L'Atenció Primària de Salut Jordi Gol I Gurina (IDIAPJGol), Barcelona, Spain. 3. Department of Physiatrist and Nursery, Faculty of Heath Sciences, University of Zaragoza, Zaragoza, Spain. 4. Faculty of Medicine and Health Sciences, Universitat International de Catalunya, Barcelona, Spain.
Abstract
BACKGROUND: Several studies have suggested that the changes in elasticity of the joint capsule and surrounding muscles during a hip long-axis distraction mobilization (LADM) could explain the pain-relieving and mobility-improving effects of the technique. OBJECTIVE: To compare the strain on the inferior ilio-femoral ligament and psoas muscle when applying three different magnitudes of force during LADM. DESIGN: Repeated measures controlled laboratory cadaveric study. METHODS: Eleven hip joints were mobilized from six fresh-frozen cadavers (mean age, 73.4 ± 5.7 years). Three magnitudes of force (low, medium and high) were applied during a hip LADM in open-packed position according to grades of joint mobilization. Strain on the inferior ilio-femoral ligament and psoas muscle were measured with strain gauges. The magnitude of the force applied during LADM was recorded. RESULTS: Strain on the inferior ilio-femoral ligament during a high-force LADM was significantly higher than strain on the inferior ilio-femoral ligament during low (p < 0.001) and medium-force LADM (p < 0.001). The strain on the inferior ilio-femoral ligament during a medium-force LADM was significantly higher than during a low-force LADM (p = 0.004). No changes in strain on psoas muscle were observed. The magnitude of force applied during LADM showed a significant progressive increase from low to high-force LADM. CONCLUSION: The different magnitudes of forces applied during LADM produce different strains on the inferior ilio-femoral ligament but not on the psoas muscle. The strain on the inferior ilio-femoral ligament during LADM depends on the magnitude of the mobilization force.
BACKGROUND: Several studies have suggested that the changes in elasticity of the joint capsule and surrounding muscles during a hip long-axis distraction mobilization (LADM) could explain the pain-relieving and mobility-improving effects of the technique. OBJECTIVE: To compare the strain on the inferior ilio-femoral ligament and psoas muscle when applying three different magnitudes of force during LADM. DESIGN: Repeated measures controlled laboratory cadaveric study. METHODS: Eleven hip joints were mobilized from six fresh-frozen cadavers (mean age, 73.4 ± 5.7 years). Three magnitudes of force (low, medium and high) were applied during a hip LADM in open-packed position according to grades of joint mobilization. Strain on the inferior ilio-femoral ligament and psoas muscle were measured with strain gauges. The magnitude of the force applied during LADM was recorded. RESULTS: Strain on the inferior ilio-femoral ligament during a high-force LADM was significantly higher than strain on the inferior ilio-femoral ligament during low (p < 0.001) and medium-force LADM (p < 0.001). The strain on the inferior ilio-femoral ligament during a medium-force LADM was significantly higher than during a low-force LADM (p = 0.004). No changes in strain on psoas muscle were observed. The magnitude of force applied during LADM showed a significant progressive increase from low to high-force LADM. CONCLUSION: The different magnitudes of forces applied during LADM produce different strains on the inferior ilio-femoral ligament but not on the psoas muscle. The strain on the inferior ilio-femoral ligament during LADM depends on the magnitude of the mobilization force.