Optimal arithmetic hip-knee-ankle angle for performing prearthritic/kinematic alignment in unicompartmental knee arthroplasty.

Background: This study aimed to investigate whether arithmetic hip-knee-ankle angle (aHKA) can be a surrogate for valgus stress radiography (VSR). Furthermore, we investigated the optimal cutoff values for preoperative radiographic parameters, thereby validating the appropriate inclusion criteria for prearthritic/kinematic unicompartmental knee arthroplasty (prearthritic-UKA).

Methods: We retrospectively analyzed 123 patients who underwent medial UKA.

Mobile bearing shows larger rollback motion than fixed bearing in total knee arthroplasty using a medial stabilising technique with a navigation system.

Purpose: This study aimed to investigate the intraoperative knee kinematics of cruciate-retaining total knee arthroplasty with a medial stabilising technique (MST-TKA) and compare the kinematics between mobile- and fixed-bearing MST-TKAs. We hypothesised that mobile-bearing MST-TKA would result in greater physiological kinematic motion than fixed-bearing MST-TKA.

Methods: Twenty-one and 20 knees underwent mobile- and fixed-bearing MST-TKAs using a navigation system (Orthopilot® ver.

The difficulty of continuing sports activities after open-wedge high tibial osteotomy in patient with medial knee osteoarthritis: a retrospective case series at 2-year-minimum follow-up.

Purpose: This study aimed to investigate the rate at which patients returned to sports after open wedge high tibial osteotomy and identify the continuity of sports activity post-operatively.

Methods: Thirty-five patients (40 knees) who underwent open-wedge high tibial osteotomy (OW-HTO) in medial knee osteoarthritis were included in this study. The mean age of the patients who underwent surgery was 55.

New Grading System for Cervical Paraspinal Soft Tissue Damage After Traumatic Cervical Spinal Cord Injury Without Major Fracture Based on the Short-T1 Inversion Recovery Mid-Sagittal MRI for Prediction of Neurological Improvements: The STIR-MRI Grade.

Study Design: Retrospective cohort study.

Objective: To develop a grading method for cervical paraspinal soft tissue damage after cervical spinal cord injury (CSCI) without major fracture based on the short T1 inversion recovery (STIR) mid-sagittal magnetic resonance image (MRI) for prediction of neurological improvements.

Methods: This study included 34 patients with CSCI without major fracture, treated conservatively for at least 1 year and graded using the STIR-MRI Grade.

Effect of medial collateral ligament release and osteophyte resection on medial laxity in total knee arthroplasty.

Purpose: The concept of medial stabilizing technique total knee arthroplasty (MST-TKA) is to minimize the medial release without the superficial layer of medial collateral ligament (MCL). However, it is unclear at what stage the proper medial laxity is obtained during surgery. The purpose of this study was to investigate the implication of deep layer of MCL (dMCL) and osteophyte resection on medial laxity during MST-TKA.

Valgus Correctability and Meniscal Extrusion Were Associated With Alignment After Unicompartmental Knee Arthroplasty.

Background: Appropriate postoperative lower limb alignment is one important element of a successful unicompartmental knee arthroplasty (UKA). To predict postoperative alignment, it is important to investigate the association between preoperative imaging evaluations and lower limb alignment after medial UKA.

Questions/purposes: (1) Do preoperative valgus stress radiographic and MRI measurements (% mechanical axis, hip-knee-ankle angle, medial meniscal extrusion distance, and osteophyte area at the medial femur and tibia) correlate with postoperative lower limb alignment after UKA; and (2) Can useful cutoffs be calculated in advance of surgery for those findings that were associated with coronal-plane overcorrection?

Methods: We retrospectively analyzed 125 patients with medial knee pain who underwent UKA from January 2012 to October 2018.

Posterior clearance increases the knee extension angle in cruciate retaining type total knee arthroplasty: Intraoperative evaluation using a navigation system.

Background: Posterior osteophyte of the femur can impinge on the tibia insert in total knee arthroplasty (TKA). Although osteophyte removal [posterior clearance (PC)] improves the flexion angle, its influence on the gaps and extension angle are unclear. This study investigated the effect of PC on the gaps and range of motion (ROM) using a navigation system, as well as PC's relationship with osteophyte size.

Severe C8 or T1 Symptoms after Cervical Laminoplasty and Related Factors: Are Tere Any Differences between C3-C6 Laminoplasty and C3-C7 Laminoplasty?

Study Design: Retrospective study.

Purpose: We experienced the situation wherein some patients had new-onset pain or dysesthesia around the ring and little fingers (C8 symptom) or ulnar aspect of the forearm (T1 symptom) after cervical laminoplasty (LP). We investigated the incidence and the cause of new C8 or T1 symptoms and the clinical outcomes after C3-C6 LP or C3-C7 LP.

Distribution and depth of bottom-simulating reflectors in the Nankai subduction margin.

Surface heat flow has been observed to be highly variable in the Nankai subduction margin. This study presents an investigation of local anomalies in surface heat flows on the undulating seafloor in the Nankai subduction margin. We estimate the heat flows from bottom-simulating reflectors (BSRs) marking the lower boundaries of the methane hydrate stability zone and evaluate topographic effects on heat flow via two-dimensional thermal modeling.

Relationship between patient-based outcome score and conventional objective outcome scales in post-operative total knee arthroplasty patients.

Purpose: Evaluations for knee osteoarthritis (OA) or post-operative total knee arthroplasty (TKA) have mainly been assessed by objective scales. Though the Knee injury and Osteoarthritis Outcome Score (KOOS) is attracting attention as a patient-based outcome score, the relationship with conventional objective scales after TKA remains controversial. The purpose of this study was to investigate the relationship between KOOS and conventional objective scales and evaluate the features of patient-based outcome scores.

Accuracy of image-free computer navigated total knee arthroplasty is not compromised in severely deformed varus knees.

In severe varus knee deformity, image-free computer navigated total knee arthroplasty (TKA) may result in a malaligned knee. The aim of this study was to compare the results of 17 severe varus knees (≥ 20°) and 81 varus knees (< 20°) that underwent image-free computer navigated TKA and analyze postoperative malalignment. Computer navigated TKA was performed according to standard protocol, and component angles and mechanical axes were evaluated postoperatively with weight bearing full-length standing radiographs.

Spinal cord shift on magnetic resonance imaging at 24 hours after cervical laminoplasty.

Study Design: A prospective study in 19 patients after cervical laminoplasty, using magnetic resonance imaging.

Objective: To evaluate the value of spinal cord shift at 24 hours after cervical laminoplasty.

Summary Of Background Data: Postoperative C5 palsy is a noticeable complication within 1 week after cervical laminoplasty.

The effect of local and general fatigue on knee proprioception.

Purpose: The purpose of this study was to compare the effects of local and general fatigue loads on knee proprioception.

Type Of Study: Experimental controlled study.

Methods: Proprioception of the knee joint was evaluated by measuring absolute angular error (AAE) at matching defined index angles before and after 2 different types of fatigue protocols (local load and general load) in 27 healthy male volunteers.

The effect of surgical approaches and tourniquet application on patellofemoral tracking in total knee arthroplasty.

The purpose of this study was to assess the influences of surgical approaches and tourniquet application on the lateral retinacular tension (LRT). Single-setting bilateral total knee arthroplasty was performed in 10 patients, and the medial parapatellar and midvastus approaches were randomly performed on each knee using tourniquet application. The LRT was measured using the buckle transducer before and after each approach.

Comparison of three techniques of anterior cruciate ligament reconstruction with bone-patellar tendon-bone graft. Differences in anterior tibial translation and tunnel enlargement with each technique.

Background: Anatomic fixation of the graft in anterior cruciate ligament reconstruction has improved stability of the reconstructed knee joint in experimental studies.

Hypothesis: Anatomic fixation of the bone-patellar tendon-bone autograft will reduce tunnel enlargement and improve clinical results.

Study Design: Prospective cohort study.

Lateral patellar retinaculum tension in patellar instability.

The patellar retinaculum is important in patellar tracking. However, little attention has been paid to the biomechanics of the retinaculum. This study assessed the change in tension of the lateral patellofemoral ligament before and after anteromedial tibial tubercle transfer for patellar instability.

Comparison of scintigraphy and magnetic resonance imaging for stress injuries of bone.

Objective: To compare findings of radiography, scintigraphy, and magnetic resonance imaging (MRI) in stress injuries of bone and evaluate changes of these findings with time correlated with clinical symptoms.

Design: Prospective study.

Setting: A primary care hospital outpatient orthopedic clinic.