In vivo ultrasound measurement of posterior femoral glide during hip joint mobilization in healthy college students

Ultrasound measurement of the effects of high, medium and low hip long-axis distraction mobilization forces on the joint space width and its correlation with the joint strain

BACKGROUND

No study has evaluated the mechanical effect of different magnitudes of long axis-distraction mobilization (LADM) force on hip joint space width (JSW) or the association between the separation of joint surfaces and the strain on hip capsular ligaments.

OBJECTIVE

To compare the joint separation when applying three different magnitudes of LADM forces (low, medium and high) and to analyse the correlation between joint separation, strain on the inferior ilio-femoral ligament and magnitude of applied force.

DESIGN

Repeated measures controlled laboratory cadaveric study.

METHODS

Three magnitudes of force were applied to 11 cadaveric hip joints (mean age 73 years). Ultrasound images were used to measure joint separation, and strain gauges recorded inferior ilio-femoral ligament strain during each condition.

RESULTS

The magnitude of joint separation was significantly different between low (0.23 ± 0.19 mm), medium (0.72 ± 0.22 mm) and high (2.62 ± 0.43 mm) forces (p < 0.001). There were significant associations between magnitude of force, joint separation and the strain on the inferior ilio-femoral ligament during LADM (r > 0.723; p < 0.001).

CONCLUSION

Hip joint separation and ligament strain during LADM are associated with the magnitude of the applied force.

Change in muscle thickness during exercise to stabilize the hip joint against a load in the ventral direction of the femoral head

[Purpose] This study aimed to measure the thickness of the muscles located on the ventral side of the hip joint and to identify the muscles involved in exercise against the load that results in femoral head translation in the ventral direction, which can be used as an index of exercise performance for the prevention and improvement of hip joint disease caused by femoral head translation. [Participants and Methods] The participants were 10 healthy young males. During the measurement task, we asked them to hold a 10 kgf load in the ventral direction to the femoral head in the supine position. We measured the thickness of the gluteus minimus, gluteus medius, tensor fascia latae, and iliopsoas both at rest and during exercise using ultrasonography. [Results] We compared muscle thicknesses at rest and during exercise and found that only the gluteus minimus had significantly lower values during exercise. We also compared the rate of change in muscle thickness and found that the gluteus minimus exhibited significantly higher values than those of the gluteus medius and tensor fasciae latae. [Conclusion] Our study indicates that the gluteus minimus is more involved than the gluteus medius, tensor fasciae latae, and iliopsoas in the exercise for the ventral displacement of the femoral head.