Quantitative evaluation of capsular and labral resistances in the hip joint using a probing device

Abstract

BACKGROUND: Probing to assess conditions of hip capsule and acetabular labrum is performed by “surgeons’ feeling”. OBJECTIVE: We investigated the resistance of the labrum and the hip capsule quantitatively while they were pulled with a probing device. METHODS: With the probing device in which a strain gauge was embedded, ten fresh frozen specimens of the pelvis and proximal femur were measured in each three surgical steps, (1) closed, (2) open, (3) closured for the capsule, and (1) intact, (2) cut, (3) repaired for the labrum. RESULTS: The mean highest resistance levels for the capsule were 9.8 N at the closed capsule, 4.1 N at the open capsule, and 8.5 N at the closured capsule. The values at the three phases were statistically significant. The mean highest resistance levels for the hip labrum were 8.2 N at the labrum intact, 4.0 N at the labrum cut, and 7.9 N at the labrum repair. The values at the three phases were also statistically significant. CONCLUSIONS: Since the quantitatively measured values in each three steps were significantly different, the values with the probing device might be useful to evaluate whether the lesion of the soft tissue exists and whether some surgical intervention works well.

A Probing Device for Quantitatively Measuring the Mechanical Properties of Soft Tissues during Arthroscopy

“…Similar results were previously reported using 10 fresh cadaver hip specimens with a similar probing device 3 level for the cut labrum (3.0-5.0 N) was statistically separated with 95% confidence from those of the intact (6.5-9.9 N) and repaired labrum (6.7-9.1 N). Therefore, a threshold for detecting lesions in the labrum might be determined, which is approximately 5 N (4-6 N on cadavers) of the highest resistance level of the labrum.…”

Comparison of Labrum Resistance Force while Pull-Probing In Vivo and Cadaveric Hips

“…We placed an arthroscopic camera into the first anterolateral portal, then inserted the probing device through the anterior portal with a thin elastic cover normally used intraoperatively in an ultrasound device (Probe cover, CIVCO Medical Solutions, Coralville, IA USA) [ 5 , 6 ], and went further into the hip joint until the tip of the device was located below the inner side of the hip labrum. The measurements of the hip labrum resistance in the anterosuperior potion were performed three times per case through the second portal ( Figure 2 ).…”

“…Ten fresh-frozen specimens of cadaver pelvis and proximal femur were used to simulate normal hip arthroscopy [ 5 ]. The donors included one man and nine women; the mean age ± SD was 60 ± 17 years (range: 35–88 years) at the time of death.…”

“…However, recent literature lacks a clear understanding of whether the stiffness of the hip labrum in the cadaveric tissues is different from that in patients. The stiffness of the in vivo hip labrum can be measured and compared with that of the cadaveric hip labrum using a probing device with a tri-axial force sensor (Probing Sensor, Takumi Precise Metal Work Manufacturing Ltd., Yao, Osaka, Japan) [ 5 , 6 ] developed by one of the authors to quantitatively measure the resistance of soft tissues in the joint.…”

A Useful Combination of Quantitative Ultrashort Echo Time MR Imaging and a Probing Device for Biomechanical Evaluation of Articular Cartilage

“…A strain gauge sensor is embedded at the top of the grip component, which connects with the probe component. In one recent paper, the condition of the acetabular labrum (intact, torn, and repaired) of could be differentiated using a prototype of this probing device [ 22 ]. A sliding feature at the grip component of the probing device ( Figure 1 ) has been added to control the distance while pulling or pushing the probe [ 21 ].…”