Association of Stability and Size of Unhealed Area With Failure After Internal Fixation for Osteochondritis Dissecans Lesions of the Knee: Radiological Evaluation Using Computed Tomography.

Background: Open reduction and internal fixation (ORIF) has been widely performed because the osteochondral component of the osteochondritis dissecans (OCD) lesion is the most suitable for reconstructing the joint structure.

Purpose: To evaluate radiological healing in terms of reconstructed bony structure after ORIF with bone graft by computed tomography (CT), to identify preoperative prognostic factors for failure, and to determine the cutoff value of radiological healing for risk of failure.

Study Design: Case-control study; Level of evidence, 3.

Single-Leg Loading Test to Predict Time to Jog and Return to Sports after Acute Lateral Ankle Sprain in Competitive Athletes.

In a previous study, the utility of a single-leg loading (SLL) test after acute lateral ankle sprain (LAS) was reported. However, whether the severity level assessed by the SLL test is associated with the time to jog and return to sports (RTS) remains unclear. Therefore, this study aimed to examine whether the time to jog and RTS differ depending on the severity level.

[Surgical Explantation of a Bioprosthesis Nine Months After Transcatheter Aortic Valve Implantation].

82-year-old female. In October 2020, the patient underwent transcatheter aortic valve implantation( TAVI)[Evolut PRO R 23 mm] via left subclavian artery approach for severe aortic valve stenosis. The patient was discharged home without any issues.

Glenoid rim morphology in young athletes with unstable painful shoulders: primarily painful vs. frankly unstable.

Background: To investigate the characteristics of glenoid rim morphology in young athletes (<40 yr) with unstable painful shoulder.

Methods: This was a retrospective case series. The inclusion criteria were as follows: (1) shoulder pain during sports activity, (2) traumatic onset, (3) no complaint of shoulder instability, and (4) soft tissue or bony lesions confirmed on imaging examinations (computed tomography and magnetic resonance imaging).

Open wedge high tibial osteotomy does not decrease patellar height relative to femur: A three-dimensional computer model analysis.

Background: Patellar height, which decreases after open wedge high tibial osteotomy (OWHTO), has conventionally been assessed by tibial references using lateral radiographs of the knee; however, changes in the proximal tibia shape after OWHTO may affect this method. We aimed to evaluate the changes in patellar height position relative to the transepicondylar axis of the femur after OWHTO using in vivo three-dimensional (3D) computer models.

Methods: Fourteen patients who underwent 3D magnetic resonance imaging (MRI) at 30° and 50° knee flexion before OWHTO and after hardware removal were included.

Factors Associated with Postoperative Knee Joint Line Obliquity After Medial Open Wedge High Tibial Osteotomy.

Background: There are still few reports on factors associated with postoperative knee joint line obliquity (KJLO).

Purpose: The purpose was to determine preoperative radiographic factors that are associated with KJLO postoperatively after open wedge high tibial osteotomy (OWHTO) using multivariable linear regression analysis and multivariable logistic regression analysis.

Study Design: Case-control study; Level of evidence, 3.

Posterior Ankle Impingement Caused by Hyaline-Like Cartilage Generation in Ballet Dancers-A Report of 2 Cases.

Posterior ankle impingement syndrome is mainly seen in ballet dancers and frequently associated with specific movements in ballet such as pointe and demi pointe in which the whole-body weight is applied to the maximally plantar flexed ankle. We performed arthroscopic debridement for 2 dedicated ballet dancers on the intervening soft tissue causing posterior ankle impingement syndrome (PAIS). In both cases, T2-weighted magnetic resonance imaging (MRI) revealed low-signal intensity of meniscus-like soft tissue without abnormal osseous findings, connecting from the posterior side of the talus to Kager's fat pad.

Quick and simple test to evaluate severity of acute lateral ankle sprain.

Background/objective: For early return to sports after a lateral ankle sprain (LAS) and recurrence prevention, effective rehabilitation and gradual return to sports should be initiated while predicting the return time based on the appropriate severity evaluation immediately after injury. However, since severity evaluations performed in previous studies required large space and stairs and involved high-revel activity, their use as a test and index to evaluate severity after LAS was not appropriate considering convenience and risk of re-injury. Therefore, a quick and simple test was developed to evaluate the severity of acute LAS.

Abrasion arthroplasty promotes improvement of degenerated femoral trochlear cartilage after medial open wedge high tibial osteotomy.

Objectives: Several studies have reported negative effects of open wedge high tibial osteotomy (OWHTO) on patellofemoral joints with cartilage degeneration and recommended performing other procedures. However, if chondral resurfacing surgery could promote improvement of cartilage degeneration in the patellofemoral joint, OWHTO would be an acceptable option. The purposes of this study were to arthroscopically evaluate the femoral trochlear articular cartilage after abrasion arthroplasty combined with OWHTO and to investigate the factors promoting improvement of that cartilage.

Anterior tibial loading on the calf enhances anterior tibial translation in the anterior cruciate ligament deficient knee in the anterior gravity radiographic view.

Background: Lateral radiograph in the prone position with the knee flexed at 15° (anterior gravity view (AGV)) is useful as a screening for anterior cruciate ligament (ACL) injuries, while it is sometimes difficult to find the side-to-side difference (SSD) in anterior tibial translation. Thus, we applied a weight (three kilograms) around the lower leg to increase anterior tibial translation. We aimed to determine whether weight load confers an advantage in visualizing anterior knee laxity in ACL injuries.

Second-look arthroscopy after anatomic anterior cruciate ligament reconstruction: Bone-patellar tendon-bone versus hamstring tendon graft.

Purpose: The purpose of this study was to compare the morphological and clinical outcomes between anatomic rectangular tunnel (ART) ACL reconstruction with a BTB graft and anatomic triple-bundle (ATB) ACL reconstruction with hamstring tendon (HST) grafts.

Methods: The anatomic ACL reconstructions were performed on 467 patients; 233 patients with ART technique and 234 with ATB procedure. ART procedure was predominantly indicated for athletes with higher motivation to return to sports and aggressiveness for muscle training.

Ultrasonographic Evaluation of the Early Healing Process After Achilles Tendon Repair.

Background: Little is known about early healing of repaired Achilles tendons on imaging, particularly up to 6 months postoperatively, when patients generally return to participation in sports.

Purpose: To examine changes in repaired Achilles tendon healing with ultrasonography for up to 12 months after surgery.

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

Anterior laxity of the knee assessed with gravity stress radiograph.

Objective: To clarify the advantage of prone position over supine position in radiographically-demonstrating anterior knee laxity measurement for anterior cruciate ligament (ACL) injury, and to optimize the radiographic technique for the ACL-deficient knees in a clinical setting.

Materials And Methods: Thirty-nine patients with unilateral ACL injury had consented to participate in this study. They were divided into two groups and subjected to the different radiographic evaluations: study 1 (20 patients); supine versus prone position with knee full-extended, and study 2 (19 patients); comparison of (1) prone position with knee full-extended (FPV), (2) prone position with knee flexed at 15° (AGV), and (3) supine position with calf put on a board at 15° of knee flexion (SGV).

Contact area between femoral tunnel and interference screw in anatomic rectangular tunnel ACL reconstruction: a comparison of outside-in and trans-portal inside-out techniques.

Purpose: The purpose of this study was to compare the femoral tunnel length, the femoral graft bending angle at the femoral tunnel aperture, and the contact area between the femoral tunnel wall and an interference screw used for fixation in anatomic rectangular tunnel anterior cruciate ligament (ACL) reconstruction (ART ACLR).

Methods: The study included 149 patients with primary ACL injury who underwent ART ACLR. Preoperatively, flexion angle of the index knee was checked under general anaesthesia.

Effects of suture site or penetration depth on anchor location in all-inside meniscal repair.

Background: To evaluate the effects of suture site or penetration depth on anchor location in all-inside meniscal repair.

Methods: Eight fresh-frozen cadaveric knees were evaluated after meniscal repair using eight FasT-Fix360 (FF360) devices (Smith & Nephew Endoscopy, Andover, MA) (16 anchors) for each knee. The penetration depth was 14mm, the distance same from the periphery to insertion point, in four knees (Group A) and that in the remaining four knees (Group B) was 18mm.

Deep peroneal nerve palsy with isolated lateral compartment syndrome secondary to peroneus longus tear: a report of two cases and a review of the literature.

Drop foot is typically caused by neurologic disease such as lumbar disc herniation, but we report two rare cases of deep peroneal nerve palsy with isolated lateral compartment syndrome secondary to peroneus longus tears. Both patients developed mild pain in the lower legs while playing sport, and were aware of drop foot. As compartment pressures were elevated, fasciotomy was performed immediately, and the tendon of the peroneus longus was completely detached from its proximal origin.

Sox9 reprogrammed dermal fibroblasts undergo hypertrophic differentiation in vitro and trigger endochondral ossification in vivo.

Strategies for bone regeneration are undergoing a paradigm shift, moving away from the replication of end-stage bone tissue and instead aiming to recapture the initial events of fracture repair. Although this is known to resemble endochondral bone formation, chondrogenic cell types with favorable proliferative and hypertrophic differentiation properties are lacking. Recent advances in cellular reprogramming have allowed the creation of alternative cell populations with specific properties through the forced expression of transcription factors.

Absorption of the bone fragment in shoulders with bony Bankart lesions caused by recurrent anterior dislocations or subluxations: when does it occur?

Background: Recently, bony defects of the glenoid in patients with traumatic anterior shoulder instability have been increasingly noticed. The bone fragment of a bony Bankart lesion is often utilized for Bankart repair, but the fragment is at times smaller than the glenoid defect. The reason for this mismatch in size is unknown.

SIK3 is essential for chondrocyte hypertrophy during skeletal development in mice.

Chondrocyte hypertrophy is crucial for endochondral ossification, but the mechanism underlying this process is not fully understood. We report that salt-inducible kinase 3 (SIK3) deficiency causes severe inhibition of chondrocyte hypertrophy in mice. SIK3-deficient mice showed dwarfism as they aged, whereas body size was unaffected during embryogenesis.

Induction of chondrogenic cells from dermal fibroblast culture by defined factors does not involve a pluripotent state.

There is a significant need for cell sources for cartilage regenerative medicine. It has been reported that the combined transduction of two reprogramming factors (c-Myc and Klf4) and one chondrogenic factor (SOX9) directly induces chondrogenic cells from mouse dermal fibroblast (MDF) culture. To gain insights into the process by which cellular characteristics are altered by transduction of c-Myc, Klf4 and SOX9, we examined marker gene expression in the MDF culture at various time points after transduction.

Generation of hyaline cartilaginous tissue from mouse adult dermal fibroblast culture by defined factors.

Repair of cartilage injury with hyaline cartilage continues to be a challenging clinical problem. Because of the limited number of chondrocytes in vivo, coupled with in vitro de-differentiation of chondrocytes into fibrochondrocytes, which secrete type I collagen and have an altered matrix architecture and mechanical function, there is a need for a novel cell source that produces hyaline cartilage. The generation of induced pluripotent stem (iPS) cells has provided a tool for reprogramming dermal fibroblasts to an undifferentiated state by ectopic expression of reprogramming factors.

Expression of dominant negative TGF-β receptors inhibits cartilage formation in conditional transgenic mice.

Although transforming growth factor-β (TGF-β) signaling has been implicated in cartilage formation in various studies, the exact role played by TGF-β in this process remains controversial. TGF-β signals are transduced through TGF-β type II receptor (TGF-βRΙΙ) and type I receptor (ALK5). Col2a1-Cre-mediated deletion of Tgfbr2 did not cause obvious defects in long bone formation, suggesting that TGF-β signals are dispensable for normal cartilage formation in the stage of condensing mesenchymal cells and chondrocytes or that related molecules can compensate for the lack of TGF-βRΙΙ.

Low-intensity pulsed ultrasound increases bone ingrowth into porous hydroxyapatite ceramic.

Synthetic porous ceramic made of hydroxyapatite (HA) has been used as a bone graft substitute. In the present study we investigated whether low-intensity pulsed ultrasound (LIPUS) accelerates bone ingrowth into the pores of HA ceramic. Application of LIPUS did not mechanically weaken porous ceramic that was immersed in water in vitro.