An increased medial proximal tibial angle of greater than 95 degrees after opening wedge high tibial osteotomy is not associated with deterioration of minimum 10-year clinical outcomes.

Purpose: The purpose of this study was to assess whether an excessively increased medial proximal tibial angle (MPTA) resulted in the deterioration of long-term clinical outcomes after opening wedge high tibial osteotomy (OWHTO) for patients with knee osteoarthritis (OA).

Methods: A total of 69 OA knees that underwent OWHTO, with follow-up for a minimum of 10 years, were retrospectively reviewed. The knee and function scores of the Knee Society Score were assessed separately, and cases with a score decline greater than or equal to the minimal clinically important difference from postoperative 1 to 10 years were defined as showing clinical deterioration.

Adjusted planning based on the joint line convergence angle improves correction accuracy in the standing position after opening wedge high tibial osteotomy.

Background: Postoperative change of the joint line convergence angle (JLCA) is known to be a factor affecting correction error in opening wedge high tibial osteotomy (OWHTO). The purpose of this study was to assess whether preoperative planning that considers change of the JLCA can achieve accurate correction in the standing position after OWHTO.

Methods: OWHTO was performed for 109 knees with osteoarthritis of the knee.

Surgical Technique and Preliminary Outcomes of Double-Level Osteotomy for Valgus Deformity.

Background: Data are limited regarding the surgical technique or outcomes of double-level osteotomy (DLO) combining medial closing-wedge distal femoral osteotomy and medial closing-wedge high tibial osteotomy in patients with moderate-to-severe valgus deformity.

Purpose/hypothesis: To describe the surgical technique and assess the short-term outcomes and surgical accuracy of DLO in patients with a moderate or severe valgus deformity. It was hypothesized that this technique would result in good clinical outcomes with precise deformity correction.

Radiologic simulation of leg length change after double level osteotomy in preoperative surgical planning.

Background: To evaluate the expected postoperative total leg length change using preoperative radiographs during surgical planning of four different methods of double level osteotomy (DLO).

Methods: This study included 34 patients (44 knees) who underwent DLO for varus knee osteoarthritis. Surgical planning was performed so that the postoperative weight bearing line ratio was 62.

Cartilage Degeneration of the Lateral Compartment of the Knee at Second-Look Arthroscopy Is Associated With Deterioration of 10-Year Clinical Outcomes After Opening-Wedge High Tibial Osteotomy.

Purpose: To identify the arthroscopic findings associated with deterioration of 10-year clinical outcomes after opening-wedge high tibial osteotomy (OWHTO) in patients with knee osteoarthritis.

Methods: A total of 114 consecutive knees of 91 patients with knee osteoarthritis who underwent OWHTO between 2007 and 2011 were retrospectively reviewed. Of these patients, those who underwent second-look arthroscopy and were followed up for a minimum of 10 years were enrolled.

Potential anatomic risk factors resulting oversized postoperative medial proximal tibial angle after double level osteotomy.

Background: Double level osteotomy (DLO) has been introduced to prevent increased postoperative joint line obliquity. However, although DLO is planned, knees with postoperative medial proximal tibial angle (MPTA) > 95° in preoperative surgical planning are present. This retrospective study aimed to evaluate risk factors for an MPTA > 95° in preoperative surgical planning for DLO in patients with varus knee osteoarthritis (OA).

Minimum 5-Year Outcomes of Osteochondral Autograft Transplantation with a Concomitant High Tibial Osteotomy for Spontaneous Osteonecrosis of the Knee with a Large Lesion.

Objective: The purpose of this study was to evaluate the mid-term clinical outcomes of osteochondral autograft transplantation (OAT) with concomitant high tibial osteotomy (HTO) in spontaneous osteonecrosis of the knee (SONK) with a large lesion.

Design: A total of 48 knees of 48 consecutive patients with SONK (lesion size ≥4 cm, no age criteria) who underwent opening wedge HTO and concomitant OAT were retrospectively investigated, and those who were followed up postoperatively for at least 5 years were included in this case series study. Clinical outcomes were evaluated using knee and function scores of Knee Society Score, radiographic outcomes were evaluated using the anatomical femorotibial angle (FTA), and these outcomes were compared between patients aged ≥70 years and <70 years.

Patient-specific instrumentation for total knee arthroplasty improves reproducibility in the planned rotational positioning of the tibial component.

Background: The purpose of this study was to evaluate the reproducibility of planned component positioning including tibial rotational alignment in patient-specific instrumentation (PSI) for total knee arthroplasty (TKA).

Methods: A total of 100 knees of 100 patients underwent TKA using PSI (n = 50) or the conventional method (n = 50). Full-length anteroposterior radiographs of the lower limb were taken in the standing position, and the coronal alignments of the femoral and tibial components were measured.

Biological Effects of High Tibial Osteotomy on Spontaneous Osteonecrosis of the Knee.

Objective: The purpose of this study was to evaluate the postoperative status of spontaneous osteonecrosis of the knee (SONK) after high tibial osteotomy (HTO) with concomitant bone marrow stimulation (BMS) using synovial fluid (SF) biomarkers.

Design: Twenty patients with SONK who underwent opening wedge HTO were enrolled. Paired SF samples from the affected knee were collected at the time of HTO surgery and at the time of plate removal.

The relationship between the ''Fujisawa point'' and anatomical femorotibial angle following simulated open wedge high tibial osteotomy.

Background: We evaluated the relationship between the weight-bearing line (WBL) ratio and anatomical femorotibial angle (FTA) by simulated open wedge high tibial osteotomy (OWHTO). This study evaluated the correlation between the ''Fujisawa point'' and FTA, and identified factors which caused deviations between the two measurement methods. We hypothesized that the Fujisawa point corresponded with 170° of the FTA.

Can double-level osteotomy prevent patellofemoral osteoarthritis progression compared with open wedge high tibial osteotomy?

Purpose: To compare radiographic, clinical, and arthroscopic findings in patellofemoral (PF) osteoarthritis (OA) between open wedge high tibial osteotomy (OWHTO) and double-level osteotomy (DLO) with the same operative indication.

Methods: After adjustment for patient age, and coronal alignment, 36 knees with OWHTO alone and 36 knees with DLO were compared. Radiographic, clinical, and arthroscopic findings were documented before osteotomy.

Surgical planning of osteotomies around the knee differs between preoperative standing and supine radiographs in nearly half of cases.

Background: To evaluate the difference in surgical planning of osteotomies around the knee between preoperative standing and supine radiographs and to identify risk factors for discrepancies in surgical planning.

Methods: This study included 117 knees of 100 patients who underwent osteotomies around the knee for knee osteoarthritis with genu varum. Surgical planning was performed so that the target point of the postoperative weight-bearing line (WBL) ratio was 62.

The range of the required anterolateral cortex osteotomy distance varied widely in biplanar open wedge high tibial osteotomy.

Background: To evaluate the anterolateral cortex distance between the lateral edge of the flange and hinge point in surgical simulations of biplanar open wedge high tibial osteotomy (OWHTO) using computed tomography (CT) images.

Methods: A total of 110 knees treated with OWHTO for medial knee osteoarthritis with varus malalignment were enrolled. Surgical simulations of biplanar OWHTO, including the transverse and ascending cuts, were performed in the standard manner using preoperative CT images.

Risk of interference between the tibial tunnel and locking screws in medial meniscus posterior root repair and open wedge high tibial osteotomy.

Purpose: To evaluate whether the frequency of interference between locking screws for the plate fixation and tibial tunnels differs depending on the tibial tunnel positions in a surgical simulation of the transtibial pull-out repair of medial meniscus posterior root tears (MMPRTs) in patients undergoing biplanar open wedge high tibial osteotomy (OWHTO).

Methods: Sixty-five patients (75 knees) who underwent OWHTO with TomoFix small plate (Depuy Synthes, PA, USA) for medial knee osteoarthritis with varus malalignment were enrolled in this study. Surgical simulation of transtibial pull-out repair of MMPRTs was performed using postoperative computed tomography images.

Deformity analysis of the lower limb on the coronal plane in patients with rheumatoid arthritis and osteoarthritis.

Objectives: To evaluate joint orientation angles of the coronal plane in patients with rheumatoid arthritis (RA) in comparison with osteoarthritis (OA).

Methods: In total, 72 patients with RA (90 knees) and 76 patients with OA (90 knees) who underwent total knee arthroplasty were enrolled. The hip-knee-ankle (HKA) angle, mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), and joint line convergence angle (JLCA) were measured on preoperative long-leg radiographs in the standing position.

Return to sports activity after opening wedge high tibial osteotomy in patients aged 70 years and older.

Background: The purpose of this study was to evaluate return to sports (RTS) after opening wedge high tibial osteotomy (OWHTO) in elderly patients and associated factors affecting RTS.

Methods: Seventy-four patients (mean age 68 years) who underwent OWHTO were enrolled. Clinical outcomes were evaluated using the Knee Society Score (KSS).

No differences in clinical outcomes and cartilage repair between opening wedge and closed wedge high tibial osteotomies at short-term follow-up: A retrospective case series analysis.

Purpose: The aim of this study was to assess differences in clinical outcomes and postoperative cartilage repair between opening wedge high tibial osteotomy (OWHTO) and closed wedge HTO (CWHTO) for medial osteoarthritis (OA) of the knee.

Methods: A total of 90 knees of 76 patients who underwent OWHTO (45 knees of 40 patients) and CWHTO (45 knees of 36 patients) was followed-up for 2 years. Cartilage repair at the medial compartment was arthroscopically classified into the following stages: Stage 1 (no reparative change); Stage 2 (partial coverage with white cartilaginous tissue); and Stage 3 (full coverage with white cartilaginous tissue).

Medialization of the mechanical axis of the tibia is related to lateralization of the tibial tuberosity in knee osteoarthritis.

Purpose: To determine whether medialization of the proximal tibia due to a varus deformity is related to lateralization of the tibial tuberosity in varus knee osteoarthritis (OA).

Methods: A total of 120 knees that underwent osteotomies around the knee for varus knee OA were enrolled. Mechanical medial proximal tibial angle (mMPTA) was measured on radiographs.

Rotational Changes in the Distal Tibial Fragment Relative to the Proximal Tibial Fragment at the Osteotomy Site after Open-Wedge High-Tibial Osteotomy.

The present study is aimed at assessing the changes in tibial rotation at the osteotomy site after an open-wedge, high-tibial osteotomy (OWHTO) and analysing the factors that affect rotational changes in the distal tibial fragment relative to the proximal tibial fragment at the same site. This study involved 53 patients (60 knees; 16 males and 37 females) with medial osteoarthritis (OA) who underwent OWHTO and preoperative and 3-month postoperative computed tomography (CT) scans. Rotational angles of the distal tibia were measured using Stryker OrthoMap 3D by comparing preoperative and postoperative CTs.

Difference in the early postoperative change of the joint line convergence angle between opening wedge and closed wedge high tibial osteotomies.

Background: The purpose of this study was to investigate the correction error associated with soft tissue balance in high tibial osteotomy (HTO) and the difference between opening wedge HTO (OWHTO) and closed wedge HTO (CWHTO).

Methods: A total of 170 knees of 130 patients (85 knees of 68 patients in OWHTO and 85 knees of 62 patients in CWHTO) were evaluated. Anteroposterior radiographs of the knee and full-length leg were taken preoperatively, immediately under general anesthesia postoperatively, 2 days, and 1 and 12 months postoperatively.

Joint line obliquity was maintained after double-level osteotomy, but was increased after open-wedge high tibial osteotomy.

Purpose: To compare the radiographic, clinical, and arthroscopic outcomes of varus osteoarthritic knees treated with an open-wedge high tibial osteotomy (OWHTO) alone or with a double-level osteotomy (DLO). It was hypothesized that treatment with DLO would maintain the joint line obliquity (JLO) and acquire better arthroscopic and clinical outcomes after surgery than OWHTO alone.

Methods: Knees with predicted medial proximal tibial angle (MPTA) > 95° were treated with OWHTO alone or with DLO.

Open-wedge high tibial osteotomy using intraoperative control of joint line convergence angle with reference to preoperative supine radiograph.

Introduction: Preoperative supine joint line convergence angle (JLCA) correlates with postoperative standing JLCA. Here, we compared the radiographic and clinical outcomes of knees with preoperative JLCAs of ≥ 4° and < 4° in open-wedge high tibial osteotomy (OWHTO). We hypothesized that the postoperative coronal alignment in both groups would not be affected by a change in JLCA if this change could predict before surgery.

Relationship between the bony correction angle and mechanical axis change and their differences between closed and open wedge high tibial osteotomy.

Background: The purpose of this study was to investigate the relationship between the bony correction angle and mechanical axis change and their differences between closed wedge high tibial osteotomy (CWHTO) and open wedge high tibial osteotomy (OWHTO).

Methods: A total of 100 knees of 89 patients who underwent OWHTO (50 knees) or CWHTO (50 knees) between 2011 and 2015 with a clinical follow-up for 1 year and a radiological follow-up for 1 month were investigated in a case control study. Anteroposterior radiographs of the knee and full-length leg were taken in the standing position using digital acquisition.