Hip flexor muscle fatigue in patients with symptomatic femoroacetabular impingement

Physical impairments in symptomatic femoroacetabular impingement: a systematic review of the evidence

“…Physical impairment outcomes reported included hip joint ROM;3 22 23 25 27 33 34 36 37 39–42 hip muscle function;22 26 29 30 31 33 simulated hip joint ROM using three-dimensional CT or three-dimensional kinematics;24 28 32 34 38 43 hip muscle volume;31 hip muscle EMG;29 30 and functional performance tasks such as single leg balance,27 squat depth and pelvic ROM,44 and number of strides per day 35. The reliability of physical impairment outcomes measured was reported in 7 out of the 23 studies.…”

Physical impairments in symptomatic femoroacetabular impingement: A Systematic review of the evidence

“…30 Studies of hip flexor size and strength reported conflicting results; SMD calculations for Mendis et al 31 revealed no significant differences in hip flexor cross-sectional area between individuals with FAI and controls. In contrast, there was a significant moderate between-group effect (ES (95% CI) 0.59 (0.36 to 0.83)) when comparing hip flexor strength in individuals with FAI to controls 29 during sustained submaximal isometric contraction. For muscle size, only one significant SMD was noted, where tensor fascia latae (TFL) was significantly larger in the non-injured leg of the person with FAI compared with healthy controls (ES (95% CI) 1.50 (0.26 to 2.74)).…”

The effect of femoro-acetabular impingement on the kinematics and kinetics of the hip joint

“…One of the significant findings raised by Rylander et al [20,35] was the presence of reverse angles in almost 50 % of their cohort, and this was also noted recently by Hunt et al [29] in one of their participants with FAI. This may hold the key for explaining some of the gait analysis results in FAI.…”

“…It is also possible that patients with FAI have subconsciously adopted impingement and pain avoidance behaviour that manifests by an altered gait pattern [23]. Another possible explanation is muscle weakness, which is poorly understood in FAI, but so far has been demonstrated in some muscle groups affecting flexion, abduction and internal rotation [35,36]. The decrease in peak extension could also be secondary to muscle contractures or early anterior capsular tightness similar to what occurs in arthritis.…”