Accuracy and reliability of tridimensional electromagnetic sensor system for elbow ROM measurement.

Background: While the precise measurement of the range of motion (ROM) of the elbow joint is important for clinical assessment and rehabilitation, problems include low accuracy and reproducibility in goniometer measurements due to the influence of soft tissue. The purpose of this study was to validate elbow joint motion analysis using a three-dimensional electromagnetic sensor system (EMS).

Methods: The accuracy and reproducibility of the EMS system were evaluated at four angles (0°, 45°, 90°, and 135°) using a model bone of the humerus and forearm.

Direct suturing quadriceps tendon to a continuous loop with a suspensory button provides biomechanically superior fixation in ACL reconstruction.

Purpose: To compare the biomechanical strength of different fixation configurations using suspensory buttons in a soft-tissue quadriceps tendon (QT) grafts in anterior cruciate ligament (ACL) reconstruction.

Methods: Forty bovine QTs, 6-cm long and 10-mm wide, were allocated into four groups with different suture configurations using suspensory buttons (n = 10 in each group): Group A, a baseball suture with a knot tied to the continuous loop with a suspensory button; Group B, same configuration as in Group A but with the knot tied at the opposite end of the baseball suture; Group C, a continuous loop with a suspensory button stitched directly to the QT with simple sutures, and Group D, a baseball suture tied directly to a suspensory button. Biomechanical testing was performed by preloading followed by cyclic loading for 500 cycles between 10 and 100 N.

A new quantitative evaluation system for distal radioulnar joint instability using a three-dimensional electromagnetic sensor.

Background: The accurate assessment of distal radioulnar joint (DRUJ) instability is still challenging as there is no established objective evaluation method. This study aimed to develop a noninvasive measurement method using a three-dimensional electromagnetic sensor system (EMS) to quantitatively assess and characterize the normal DRUJ movement in healthy volunteers.

Methods: The DRUJ movement was mimicked using both a block model and saw bone.

The quantitative evaluation of anterior drawer test using an electromagnetic measurement system.

The anterior drawer test (ADT) is the gold standard examination for the diagnosis of anterior talofibular ligamentinsufficiency,although there is noquantitative evaluation of ADT that is generally usable and reliable.An electromagnetic sensor (EMS)has been used to quantitatively evaluate joint kinematics, and has a high potential to be applied to the ankle joint. The aim of this study was to validatethe EMS measurement of the ADTin comparison to the fluoroscopic evaluationand to evaluate the reproducibility of the EMS measurement.

Migration Measurement of Pins in Postoperative Recovery of the Proximal Femur Fractures Based on 3D Point Cloud Matching.

Internal fixation is one of the most effective methods for the treatment of proximal femur fractures. The migration of implants after the operation can seriously affect the reduction of treatment and even cause complications. Traditional diagnosis methods can not directly measure the extent of displacement.

Radial Meniscal Tears Are Best Repaired by a Modified "Cross" Tie-Grip Suture Based on a Biomechanical Comparison of 4 Repair Techniques in a Porcine Model.

Background: The tie-grip suture can fix radial tears more rigidly than simple conventional sutures. However, one shortcoming is the residual gap at the central margin of the tear. The tie-grip suture was modified to address this issue and named the "cross tie-grip suture.

Patient-Reported and Quantitative Outcomes of Anatomic Anterior Cruciate Ligament Reconstruction With Hamstring Tendon Autografts.

Background: The pivot-shift test has become more consistent and reliable and is a meaningful outcome measurement after anterior cruciate ligament reconstruction (ACLR).

Purpose/hypothesis: The purpose of this investigation was to assess patient-reported outcomes (PROs) and the quantitative pivot shift (QPS) preoperatively, at time zero immediately after anatomic ACLR, and after 24 months as well as the relationship between PROs and the QPS. It was hypothesized that anatomic ACLR would restore rotatory stability measured by the pivot-shift test and that QPS measurements would be positively correlated with PROs.

Plantar pressure sensors indicate women to have a significantly higher peak pressure on the hallux, toes, forefoot, and medial of the foot compared to men.

Background: Sex-related differences of plantar pressure distribution during activities should be thoroughly inspected as it can help establish treatment and prevention strategies for foot and ankle problems. In-shoe measurement systems are preferable without space and activity restrictions; however, previously reported systems are still heavy and bulky and induce unnatural movement. Therefore, a slim and light plantar pressure sensor was newly developed to detect the effect of sex difference on plantar pressure during standing and walking.

Analysis of anterior tibial subluxation to the femur at maximum extension in anterior cruciate ligament-deficient knees.

Purpose: The factors affecting anterior tibial subluxation (ATS) have not yet been well examined. To assess the factors affecting ATS in anterior cruciate ligament (ACL)-deficient knees.

Methods: One hundred twenty-four patients with unilateral ACL injuries were included.

Anatomic Anterior Cruciate Ligament Reconstruction Using Hamstring Tendons Restores Quantitative Pivot Shift.

Background: It is still uncertain how surgical reconstruction of the anterior cruciate ligament (ACL) is able to restore rotatory laxity of the involved joint. The desired amount of restraint applied by the ACL graft, as compared with the healthy knee, has not been fully clarified.

Purpose: To quantify the ability of single-bundle anatomic ACL reconstruction using hamstring tendons in reducing the pivot-shift phenomenon immediately after surgery under anesthesia.

Stress distribution is deviated around the aperture of the femoral tunnel in the anatomic anterior cruciate ligament reconstruction.

Purpose: Final tunnel location in the anterior cruciate ligament (ACL) reconstruction is unpredictable due to tunnel widening and/or transposition. The mechanical stress around the tunnel aperture seems to be a major factor but is not fully investigated. The purpose of this study was to measure the stress from the ACL graft around the tunnel aperture when the ACL graft tension reaches its peak.

Comparison Between Intra- and Extra-articular Tension of the Graft During Fixation in Anterior Cruciate Ligament Reconstruction.

Purpose: To evaluate the tension deprivation through the tunnels with and without preconditioning at the time of fixation, and the influences of cyclic loading and pretensioning on graft tension in anatomic single bundle anterior cruciate ligament (ACL) reconstruction using a hamstring tendon.

Methods: Nine fresh-frozen cadaveric knees underwent anatomic ACL reconstruction using hamstring grafts. Each specimen was examined to ensure that there was no severe osteoarthritic change, ligament insufficiency, or torn menisci by manual and arthroscopic evaluation.

Local Administration of Simvastatin Stimulates Healing of an Avascular Meniscus in a Rabbit Model of a Meniscal Defect.

Background: Repair of an avascular meniscus is challenging because of its low capacity for healing. Several reports have shown that simvastatin stimulates the anabolic activity of intervertebral fibrochondrocytes, suggesting that simvastatin may be used for the treatment of meniscal defects.

Purpose: To test whether the local administration of simvastatin stimulates healing of an avascular meniscus in rabbits.

Biomechanical Function of Anterior Cruciate Ligament Remnants: Quantitative Measurement With a 3-Dimensional Electromagnetic Measurement System.

Purpose: To evaluate quantitatively the biomechanical function of anterior cruciate ligament (ACL) remnants in patients with ACL injuries. Anterior tibial translation (ATT) with KT-1000 and during the Lachman test with an electromagnetic measurement system (EMS) and tibial acceleration during the pivot shift test with EMS were measured.

Methods: A total of 121 unilateral ACL injuries were examined.

Quantitative comparison of the pivot shift test results before and after anterior cruciate ligament reconstruction by using the three-dimensional electromagnetic measurement system.

Purpose: Tibial acceleration during the pivot shift test is a potential quantitative parameter to evaluate rotational laxity of anterior cruciate ligament (ACL) insufficiency. However, clinical application of this measurement has not been fully examined. This study aimed to measure and compare tibial acceleration before and after ACL reconstruction (ACLR) in ACL-injured patients.

Three-dimensional analysis of bone tunnel changes after anatomic double-bundle anterior cruciate ligament reconstruction using multidetector-row computed tomography.

Background: The femoral and tibial bone tunnel enlargement after anatomic double-bundle anterior cruciate ligament reconstruction (ACL-R) has not been fully documented.

Purpose: To evaluate the region-specific bone tunnel volume changes and those transpositions using 3-dimensional multidetector-row computed tomography (MDCT) after anatomic double-bundle ACL-R.

Study Design: Case series; Level of evidence, 4.

Reduction of tunnel enlargement with use of autologous ruptured tissue in anterior cruciate ligament reconstruction: a pilot clinical trial.

Purpose: To compare the tunnel enlargement of double-bundle (DB) anterior cruciate ligament reconstruction (ACLR) with and without suturing of autologous ruptured tissue to hamstring graft in patients with subacute anterior cruciate ligament injury.

Methods: Ten patients with subacute (≤3 months after injury) anterior cruciate ligament rupture were randomly allocated to undergo DB ACLR with suturing of the ruptured tissue to hamstring graft (n = 5) or conventional DB ACLR (n = 5). When autologous ruptured tissue was used, remnant ruptured tissue was then harvested, divided into 4 pieces, placed between the loops at the distal and proximal portions of the graft, and secured with the suture.

Matching articular surfaces of selected donor and recipient sites for cylindrical osteochondral grafts of the femur: quantitative evaluation using a 3-dimensional laser scanner.

Background: Autogenous osteochondral grafting has been widely performed as a treatment for focal osteochondral defects. In this procedure, it is important to match the shape of the articular surface between the donor site and recipient site to reproduce the original articular surface of the femur.

Purpose: To investigate the ideal matching patterns of articular surface profiles of donor and recipient sites for autogenous osteochondral grafting of the femur using a 3-dimensional laser scanning method.

A new technique of bone thickness measurement for pedicle screw insertion safety purpose.

Pedicle Screw (PS) was originally accomplished for Spinal fixation but it has several limitations. If the pedicle screw passes though the cortex bone in surgery, it has a risk to damage the spinal cord and vertebral artery, which can be caused to a serious problem such as paralysis. Therefore, it should be avoided by all possible means.

Biomechanical characteristics of 3 pivot-shift maneuvers for the anterior cruciate ligament-deficient knee: in vivo evaluation with an electromagnetic sensor system.

Background: A disadvantage of pivot-shift maneuvers is that the examiner has to subjectively evaluate the degree of pivot shift observed. It is unknown whether the various maneuvers are biomechanically identical.

Purpose: To compare biomechanical features of 3 clinical maneuvers for the anterior cruciate ligament (ACL)-deficient knee: the pivot-shift test, the jerk test, and the N-test.

Biomechanical analysis of the knee with partial anterior cruciate ligament disruption: quantitative evaluation using an electromagnetic measurement system.

Purpose: To investigate the biomechanical function of anterior cruciate ligament (ACL) remnants in ACL-deficient knees with both partial and complete tears.

Methods: Twenty partial ACL-deficient (group P), 20 complete ACL-deficient (group C), and 40 contralateral ACL-intact knees were examined. The end point during the Lachman test, side-to-side differences of KT-1000 measurements, and the pivot shift test were evaluated.

Differences in Knee Kinematics Between Awake and Anesthetized Patients During the Lachman and Pivot-Shift Tests for Anterior Cruciate Ligament Deficiency.

Background: The Lachman and pivot-shift tests have been widely used for detecting anterior cruciate ligament (ACL) deficiency. However, it still remains unclear whether these manual tests can be quantified accurately while patients are awake.

Purpose: To assess the differences in knee kinematics of awake and anesthetized patients.

Modified metaphyseal-loading anterolaterally flared anatomic femoral stem: five- to nine-year prospective follow-up evaluation and results of three-dimensional finite element analysis.

We have designed a proximal-fitting, anterolaterally flared, arc-deposit hydroxyapatite-coated anatomical femoral stem (FMS-anatomic stem; KYOCERA Medical, Osaka, Japan) for cementless total hip arthroplasty (THA) for Japanese patients with dysplastic hip osteoarthritis, using a nonlinear three-dimensional finite element analysis simulating loading conditions. The Anatomic Fit stem was modified in the region of the arc-sprayed surface, to allow more proximal appearance of spot welds. The aim of the present study was to analyze the clinical and radiographic outcomes of patients who underwent THA using this stem.

An analysis of surface profile for cylindrical osteochondral grafts of the knee quantitative evaluation using a three-dimensional laser scanner.

Purpose: To investigate the congruency of the articular cartilage surface of the knee between the recipient and donor site during autogenous osteochondral grafting using a three-dimensional (3D) laser scanning.

Methods: Six cadaveric knees were included in this study. The 3D profiles of the articular surface were obtained by a 3D laser scanner (FastSCAN(®), Polhemus).