Comparison of ultrasonographic evaluation methods for ankle syndesmosis in non-weight bearing and weight bearing conditions.

BACKGROUND: This study aimed to investigate ankle syndesmosis in healthy subjects under non-weight bearing (NWB) and weight bearing (WB) conditions using two US methods. METHODS: The anterior tibiofibular clear space (ATFCS) was measured in healthy subjects in NWB and WB conditions using two US procedures. Method 1 measured 10 mm above the ankle joint and Method 2 measured 30° from the line of 10 mm above the ankle joint. RESULTS: A total of 60 ankles from 30 subjects (male/female, 15/15) were included. There was a significant difference in the ATFCS between the two US methods (p < 0.001), and Method 2 was better at detecting the change in diastasis from NWB to WB conditions. The ATFCS was significantly greater on WB than on NWB, irrespective of the US method. CONCLUSIONS: Method 2 was better at detecting diastasis of the syndesmosis from NWB to WB conditions. The influence of WB needs to be considered when evaluating syndesmosis using US. LEVEL OF EVIDENCE: Cross-sectional cohort study; Level of evidence, Ⅳ.

Retromalleolar groove morphology of the tibialis posterior tendon (TPT) in patients without TPT pathology evaluated by axial computed tomography scans.

BACKGROUND: This study aimed to evaluate the shape of the retromalleolar groove of the tibialis posterior tendon (TPT) using computed tomography (CT). METHODS: CT images of patients with foot or ankle pathologies were retrospectively reviewed. The morphology of the retromalleolar groove of the TPT was assessed at two different levels: the ankle joint and 10 mm above the ankle joint. The groove shape was classified into three types; concave, flat, or irregular. In cases with concave grooves, the width and depth of the grooves were measured. RESULTS: Of the 116 ankles from 116 subjects included in this study, 80.2 % showed a shallow concave shape (mean depth, 1.6 mm) at the two scan levels. The shape and width of the groove differed significantly by gender, although there was no significant difference in the groove depth. CONCLUSION: Approximately 80% showed a shallow concave groove of the TPT. The groove characteristics differed by gender, although there was no significant difference in the groove depth. LEVEL OF EVIDENCE: Cross-sectional cohort study; Level of evidence, Ⅳ.

Time elapsed from definitive diagnosis to surgery for osteonecrosis of the femoral head: a nationwide observational study in Japan.

OBJECTIVES: This study documents the time elapsed from the diagnosis of osteonecrosis of the femoral head (ONFH) to surgery, exploring the factors that influence ONFH severity. DESIGN: Retrospective observational study of a nationwide database. SETTING: The Kaplan-Meier method with log-rank tests was applied to examine the period from definitive diagnosis of ONFH to surgery using any surgery as the end point. For bilateral cases, the date of the first surgery was the endpoint. PARTICIPANTS: This study included 2074 ONFH cases registered in 34 university hospitals and highly specialised hospitals of the multicentre sentinel monitoring system of the Japanese Investigation Committee between 1997 and 2018. MAIN OUTCOME MEASURE: The primary outcome was the time from diagnosis to surgery. The secondary outcome was the proportion of subjects remaining without surgery at 3, 6 and 9 months, and at 1, 2 and 5 years after diagnosis. RESULTS: The median time to surgery was 9 months (IQR 4-22 months) after diagnosis of ONFH. The time to surgery was significantly shorter in the alcohol alone group and the combined corticosteroid and alcohol group than in the corticosteroid alone group (p=0.018 and p<0.001, respectively), in early stage ONFH with no or mild joint destruction (stages II and III, p<0.001), and with joint preserving surgery (p<0.001). The proportion without surgery was 75.8% at 3 months, 59.6% at 6 months, 48.2% at 9 months, 40.5% at 1 year, 22.2% at 2 years and 8.3% at 5 years. CONCLUSION: ONFH has been considered to be an intractable disease that often requires surgical treatment, but the fact that surgery was performed in more than half of the patients within 9 months from diagnosis suggests severe disease with a significant clinical impact. TRIAL REGISTRATION NUMBER: Chiba University ID1049.

Risk factors of failure results after double-bundle reconstruction with autogenous hamstring grafts for isolated posterior cruciate ligament rupture cases.

Posterior tibial translation (PTT) after double-bundle posterior cruciate ligament (PCL) reconstruction has sometimes occurred. Purpose of this study is to identify the risk factors for postoperative PTT after double-bundle PCL reconstruction with a hamstring autograft. Comparing the results of bilateral gravity sag view (GSV) at 12 months after surgery, over 5-mm PTT was defined as 'failure' in this study. Of 26 isolated PCL reconstruction cases, over 5-mm PTT was seen in 7 cases (group F: 9.57 ± 1.28 mm), and 19 cases had less than 5 mm (group G: 2.84 ± 1.29 mm). Age, sex, body mass index (BMI), preoperative GSV, posterior slope angle of the tibia, anterolateral bundle (ALB) and posteromedial bundle (PMB) graft diameters, and tibial tunnel diameter were evaluated. The two groups were compared with the 2 × 2 chi-squared test, the Mann Whitney U-test, and Spearman's rank correlation coefficient. Multivariate logistic regression analysis was also performed to determine the risk factor. Statistical significance was indicated as p < 0.01 for correlation with postoperative PTT, and as p < 0.05 for all other comparisons. Mean age (group G 31.8 ± 12.5 vs group F 34.9 ± 15.9 years), sex (male/female: 15/4 vs 3/4), BMI (25.6 ± 4.6 vs 24.9 ± 3.9 kg/m2), preoperative GSV (11.3 ± 2.2 vs 11.6 ± 2.9 mm), PMB diameter (5.37 ± 0.33 vs 5.36 ± 0.48 mm), and tibial tunnel diameter (9.32 ± 0.58 vs 9.29 ± 0.49 mm) showed no significant differences. ALB diameter was significantly greater in group G (7.0 ± 0.5 mm) than in group F (6.5 ± 0.29 mm; p = 0.022). There was also a significant difference in posterior tibial slope angle (group G 9.19 ± 1.94 vs group F 6.54 ± 1.45, p = 0.004). On Spearman rank correlation coefficient analysis, ALB diameter GSV (correlation coefficient: - 0.561, p = 0.003) and posterior tibial slope angle (correlation coefficient: - 0.533, p = 0.005) showed a significant correlation with postoperative PTT. Multivariate logistic regression analysis showed that ALB diameter (OR 19.028; 95% CI 1.082-334.6; p = 0.044) and posterior slope angle of tibia (OR 3.081; 95% CI 1.109-8.556; p = 0.031) were independently associated with postoperative PTT, respectively. In double-bundle PCL reconstruction with hamstring, smaller ALB graft diameter and lower (flatted) tibial slope angle were considered risk factors for postoperative PTT.

Is the Small Ossicle of Type 1 Accessory Navicular a Cause of Foot Pain?-A Case Report.

Background and objectives: An accessory navicular (AN) bone is often classified into types 1-3 according to the Veitch classification, and symptomatic type 1 patients usually receive non-surgical treatment. However, there are cases in which AN cannot be classified into one of these three types using this classification system, and the small ossicle of type 1 AN may not be the cause of foot pain. This report aimed to present a case of symptomatic type 1 AN that required surgical treatment without the excision of the small ossicle after long-term conservative treatment had failed. Case presentation: A 15-year-old girl who was diagnosed with symptomatic type 1 AN was referred to our department. Medial-side foot pain had prevented her from playing soccer well. She had been treated conservatively for type 1 AN for more than 12 months at several orthopedic clinics. Tenderness of the prominent navicular tubercle was identified, and computed tomography and magnetic resonance imaging findings suggested that the cause of her foot pain was derived from the prominent navicular tubercle not the small ossicle itself. Osteotomy of the prominent navicular tubercle with the advancement of the tibialis posterior tendon, without excision of the ossicle, was performed. At the 12-month follow-up examination, she was completely free from foot pain, and the patient-reported outcome measures were excellent. She now plays soccer at the pre-injury level. Conclusions: We report the case of a patient with symptomatic type 1 AN who underwent osteotomy of the prominent navicular tubercle with advancement of the tibialis posterior tendon, without excision of the ossicle, and who showed favorable short-term clinical outcomes. The evaluation of symptomatic patients with AN based on the Veitch classification alone may lead to inappropriate management. The small ossicle of type 1 AN was not the cause of foot pain in the present case.

Retrograde Autologous Talar Osteocancellous Bone Grafting for the Treatment of Osteochondral Lesions of the Talus: A Technical Note.

Osteochondral lesions of the talus (OLT) are common injuries in young athletes. Various kinds of surgical procedures are available for orthopaedic surgeons, but which surgical technique is the best remains controversial. Many surgical procedures require malleolar osteotomy to obtain appropriate surgical exposure to the OLT because of the anatomic characteristics of the ankle joint. However, malleolar osteotomy is invasive and has a potential risk of complications, such as tibial chondral damage and pseudoarthrosis. This article aims to introduce a novel surgical procedure for the treatment of OLTs: retrograde autologous talar osteocancellous bone grafting without the need for osteotomy and harvesting a graft from anywhere other than the talus. First, an arthroscopic evaluation is performed to verify the location, size, and cartilage quality of the OLT as well as concomitant lesions. After confirming the position of the guide pin using a guide device arthroscopically, a talar osteocancellous bone plug is harvested using a coring reamer. The OLT of the harvested talar bone plug is removed, and under arthroscopy, the talar osteocancellous bone plug is retrogradely inserted into the talar bone tunnel. To stabilize the implanted bone plug, one or two bioabsorbable pins are inserted from the lateral wall of the talus while applying counterforce to the articular surface of the bone plug. The present surgical technique can minimally invasively address the OLT without the need for malleolar osteotomy and harvesting a graft from the knee joint or iliac bone.

Ureter position and risk of ureteral injury during lateral lumbar interbody fusion.

BACKGROUND: Ureteral injury during lateral lumbar interbody fusion (LLIF) is uncommon. However, it is a serious complication that may require additional surgery should it occur. The objective of this study was to evaluate whether there was any change in the position of the left ureter between preoperative biphasic contrast-enhanced CT scanned in the supine position and intraoperative scanning in the right lateral decubitus position after stent placement, to assess the risk of ureteral injury in the actual surgical position. METHODS: The position of the left ureter scanned with the O-arm navigation system with the patient in the right lateral decubitus position and its position on preoperative biphasic contrast-enhanced CT images scanned with the patient in the supine position were investigated comparing their positions at the L2/3, L3/4, and L4/5 levels. RESULTS: The ureter was located along the interbody cage insertion trajectory in 25 of 44 disc levels (56.8%) in the supine position, but in only 4 (9.5%) in the lateral decubitus position. The proportion of patients in whom the left ureter was located lateral to the vertebral body (along the LLIF cage insertion trajectory) at each level was 80% in the supine position and 15.4% in the lateral decubitus position at the L2/3 level, 53.3% in the supine position and 6.7% in the lateral decubitus position at the L3/4 level, and 33.3% in the supine position and 6.7% in the lateral decubitus position at the L4/5 level. CONCLUSION: The proportion of patients in whom the left ureter was located on the lateral surface of the vertebral body when the patient was in the actual surgical position (lateral decubitus position) was 15.4% at the L2/3 level, 6.7% at the L3/4 level, and 6.7% at the L4/5 level, suggesting that caution is required during LLIF surgery.

Insertion sites of the muscles attached to the clavicle: a cadaveric study of the clavicle.

BACKGROUND: Clavicle fractures are common injuries, especially in young, active individuals. Operative treatment is recommended for completely displaced clavicle shaft fractures, and plate fixation is stronger than the use of intramedullary nails. Few studies have reported on iatrogenic injuries to the muscle attached to the clavicle during fracture surgery. The aim of this study was to clarify the area of the insertion sites of muscles attached to the clavicle in Japanese cadavers using gross anatomy and three-dimensional (3D) analysis. We also aimed to compare the effects of anterior plate templating and superior plate templating on clavicle shaft fractures using 3D images. METHODS: Thirty-eight clavicles from Japanese cadavers were analyzed. We removed all clavicles to identify the insertion sites and measured the size of the insertion area of each muscle. Three-dimensional templating was performed on both the superior and anterior plates of the clavicle using data obtained from computed tomography. The areas covered by these plates on the muscles attached to the clavicle were compared. Histological examination was performed on four randomly selected specimens. RESULTS: The sternocleidomastoid muscle was attached proximally and superiorly; the trapezius muscle was attached posteriorly and partly superiorly; and the pectoralis major muscle and deltoid muscles were attached anteriorly and partially superiorly. The non-attachment area was located mainly in the posterosuperior part of the clavicle. It was difficult to distinguish the borders of the periosteum and pectoralis major muscles. The anterior plate covered a significantly broader area (mean 6.94 ± 1.36 cm2) of the muscles attached to the clavicle than did the superior plate (mean 4.11 ± 1.52 cm2) (p < 0.0001). On microscopy, these muscles were inserted directly into the periosteum. CONCLUSION: Most of the pectoralis major and deltoid muscles were attached anteriorly. The non-attachment area was located mainly from the superior to posterior part of the clavicle midshaft. Both macroscopically and microscopically, the boundaries between the periosteum and these muscles were difficult to demarcate. The anterior plate covered a significantly broader area of the muscles attached to the clavicle than that by the superior plate.

Risk factors associated with throwing injuries in young baseball players.

BACKGROUND: Few studies have retrospectively analyzed the relationship between joint range of motion (ROM) and muscle flexibility and shoulder and elbow throwing injuries in a large number of elementary school baseball players. The purpose of this study was to retrospectively identify the physical factors related to shoulder and elbow throwing injuries in younger baseball players. METHODS: A total of 2466 younger baseball players belonging to our Prefecture Rubber Baseball Federation who participated in medical check-ups from 2016 to 2019 were analyzed. Players completed a questionnaire and had a medical check-up that included a physical examination and ultrasonography. ROM (internal rotation [IR] angle and external rotation angle) of the shoulder and hip and the finger-to-floor distance and heel-to-buttock distance were measured. The straight leg raise was also performed. The results of two groups (normal group and injury group) were compared using the χ2 test, Mann-Whitney U test, and Student t test. Stepwise forward logistic regression models were developed to identify risk factors. RESULTS: On univariate analysis, nine of the 13 evaluated items showed significant decreases in ROM and muscle flexibility in the injury group. On multiple logistic regression analysis, grade, finger-to-floor distance, IR angle of the dominant side shoulder, and IR angle of the nondominant side hip were significantly associated with the occurrence of throwing injuries. Decreased total shoulder angle was observed not only on the dominant side but also on the nondominant side in the injury group. CONCLUSION: Decreased ROM and muscle flexibility were risk factors for baseball-related throwing injuries in elementary school baseball players. To prevent shoulder and elbow throwing injuries, players, coaches, medical staff, and parents need to be aware of these findings.

A Traumatic Neuroma Formation Following Fasciotomy for the Treatment of Tibialis Anterior Muscle Herniation: A Case Report.

Muscle herniation of the lower extremity, such as tibialis anterior muscle herniation (TAMH), is not a rare cause of leg pain in athletes. However, a few studies have reported surgical treatment for TAMH, and the optimal surgical procedure remains controversial. Fasciotomy was reported to be effective for patients with TAMH. However, this procedure would be associated with a risk of intraoperative injury to the superficial peroneal nerve (SPN), although no previous literature has reported this complication. This case report aimed to report a case of bilateral TAMHs in which a traumatic neuroma of the SPN developed after fasciotomy. A 16-year-old baseball player presented with painful swelling lesions of the bilateral lower extremities (1 lesion on the right, 3 lesions on the left) after sports activities. An ultrasonographic evaluation showed swelling lesions of the anterolateral parts of the bilateral lower extremities in the standing position after dashing, while these lesions were not detected in the supine position. A fasciotomy of the crural fascia was performed after conservative treatment failed. Several days after surgery, the patient presented with weakened touch sensation over the dorsal area of the left foot. At the three-month follow-up examination, a swelling lesion with hard elasticity was identified. The palpation of this lesion caused a radiating sensation in the area supplied by the SPN. He was able to return to playing baseball six months after surgery. The patient was asymptomatic without palpation of the traumatic neuroma of the SPN at the latest follow-up examination. In conclusion, the present case report suggests that orthopedic surgeons need to consider the risk of iatrogenic injury to the SPN during fasciotomy for the treatment of TAMHs. However, there may be a risk of injuring the SPN because of the many variants of the course of the SPN within the compartment of the lower extremities.

Remnant-Preserved Single-Bundle Anterior Cruciate Ligament Augmentation in Multi-ligamentous Knee Reconstruction.

This study was conducted to present remnant-preserving anterior cruciate ligament (ACL) augmentation as a useful option for partial ACL injury in multiligament knee injury (MLKI) cases, which may also contribute to conserving graft resources. The present study involved patients diagnosed with MLKI at our institute from Spring 2006 to February 2021. A total of 71 MLKI cases were provided surgery due to knee instability and disability. For every patient, an arthroscopic diagnostic was performed to ensure that ACL tear and a remnant were present. When the ACL remnant was classified into group 2, 3, or 4 of Nakamae's classification, remnant-preserved single bundle ACL augmentation was performed. Graft selection and the combination of injured ligaments were evaluated. The side-to-side difference under an anterior tibial load of 134 N with an arthrometer and the leg symmetry index at 60 degrees/s were measured. The present procedure was performed for five cases (male/female: 4/1, mean age: 33.6 years). The mean follow-up period was 26.4 months. The combination of torn ligaments was as follows: 3 cases of ACL + medial collateral ligament, one case of ACL + posterior cruciate ligament, and one case of ACL + posterolateral corner. An ACL augmentation graft was performed using an ipsilateral gracilis tendon in 2 cases, a contralateral full semitendinosus tendon in 2 cases, and the ipsilateral distal 1/2 of the semitendinosus tendon in 1 case. The mean side-to-side difference was 1.07 ± 0.4 mm. The mean leg symmetry index was 82.6 ± 12.2% in knee extension and 96.3 ± 9.9% in knee flexion. Although the present study was a small case series, the remnant-preserved single-bundle ACL augmentation for MLKI surgery provided good clinical outcome and conserved the graft resource. Even in the MLKI case, this technique is one of the useful surgical options. The level of evidence of this study is level IV (case series).

Risk Factors of Loss of Knee Range of Motion after Primary Anterior Cruciate Ligament Reconstruction following Preoperative Recovery of Knee Range of Motion.

The loss of knee range of motion (ROM) is not an uncommon complication after anterior cruciate ligament reconstruction (ACLR). However, the risk factors of loss of knee ROM remain debatable. The purpose of this study was to evaluate the incidence and risk factors of loss of knee ROM at 12 months after primary ACLR performed after regaining full knee ROM preoperatively. Consecutive patients who underwent primary ACLR after regaining full ROM between January 2014 and January 2020 were retrospectively reviewed. Patients who received a surgical arthrolysis within 12 months after ACLR or those who had a loss of knee ROM at 12 months postoperatively were defined as the loss of ROM group. Possible risk factors of loss of knee ROM, including patient demographic, preoperative, surgical, and postoperative factors, were assessed. The notch wide index and radiographic parameters of the tibial spines; medial tibial spine height/tibial length (TL), lateral tibial spine height (LTSH)/TL, and tibial spine width (TSW)/TL, were also assessed. A total of 141 patients (141 knees) were included (mean age, 25.8 ± 11.4 years; male/female, 56/85). Of the 141 patients, three received surgical arthrolysis within 12 months, and 23 had a loss of knee ROM at 12 months after ACLR. On comparing patients with and without loss of knee ROM, significant differences were found in the age (p = 0.04), LTSH/TL (p = 0.02), and TSW/TL (p = 0.02). A multivariate regression analysis showed that the age (odds ratio [OR]; 1.05, 95% confidence interval [CI]: 1.01-1.09, p = 0.02), LTSH/TL (OR: 1.44, 95% CI: 1.01-2.1, p = 0.04), and TSW/TL (OR: 0.79, 95% CI: 0.65-0.97, p = 0.02) were identified as significant independent risk predictors of loss of knee ROM. This study showed that the incidence of loss of knee ROM at 12 months after primary ACLR was 18.4% (26/141). An older age, a higher LTSH/TL, and a smaller TSW/TL may be associated with loss of knee ROM at 12 months after ACLR.

The anterior talofibular ligament ratio was greater in young men with generalized joint laxity than in those without generalized joint laxity.

PURPOSE: This study aimed to evaluate the relationship between generalized joint laxity (GJL) and stress ultrasonographic (US) findings of the anterior talofibular ligament (ATFL) of healthy young men. METHODS: The ATFL lengths of healthy young men were consecutively measured in the stress and nonstress positions. The ATFL ratio was calculated as an indicator of lateral ankle laxity. GJL was evaluated using the Beighton score (BS), and a BS of ≥ 5 was considered GJL. The manual anterior drawer test (ADT) was also performed. The results of stress US and ADT were compared between subjects with and without GJL, and the correlation between GJL and US findings was examined. RESULTS: A total of 13 subjects with GJL and 95 without GJL were included in the study. The mean BSs in the GJL and no-GJL groups were 5.9 ± 0.9 and 1.1 ± 1.3, respectively (p < 0.0001). The GJL group showed a higher grade of ADT than the no-GJL group (p < 0.0001). Significant differences were found in the stress ATFL length (23.6 ± 1.8 mm vs. 21.7 ± 1.8 mm, p = 0.002) and ATFL ratio (1.15 ± 0.06 vs. 1.07 ± 0.03, p < 0.0001) between the GJL and no-GJL groups. Spearman's correlation coefficients showed a moderate correlation between the BS and ATFL ratio (r = 0.45, p < 0.0001). CONCLUSION: The present study showed significant differences in the ATFL ratio and stress ATFL length between young men with and without GJL. The BS was moderately correlated with the lateral ankle laxity in this population. LEVEL OF EVIDENCE: Level IV.

Investigation of cryotherapy for pain relief after arthroscopic shoulder surgery.

BACKGROUND: Recently, cryotherapy has become a common practice for postoperative pain management. The current accepted practice in Japan is the use of cryotherapy at 5 °C after arthroscopic shoulder surgery. However, this therapy has been reported to be highly intense because the sustained low temperature causes discomfort for patients. The optimum temperature and duration of cooling required for comfortable and effective cryotherapy after arthroscopic shoulder surgery were investigated. METHODS: Because pain levels might differ depending on the condition, we selected 52 patients with rotator cuff injuries, which were the most common disorders indicated for arthroscopic shoulder surgery. Patients were treated with cryotherapy at 5 °C or 10 °C for 16 h or 24 h. The pain level was determined using the visual analogue scale, and deep shoulder joint temperatures were recorded at different time points for analysis. RESULTS: Pain after arthroscopic shoulder surgery was found to be related to the presence of a brachial plexus block using the interscalene approach during surgical anesthesia. To obtain effective analgesia with cryotherapy, the cooling temperature and duration of cryotherapy had to be changed based on the presence or absence of the brachial plexus block. Patients who received brachial plexus blocks had the lowest recorded pain scores after receiving cryotherapy at 5 °C for 24 h after surgery. Patients who did not receive the block had the lowest recorded pain scores when receiving cryotherapy at either 5 °C for 16 h or 10 °C for 24 h. CONCLUSIONS: Using universal cryotherapy intensity and duration settings regardless of the use of other interventions is likely to unintentionally increase postoperative pain levels. This study revealed that cryotherapy at 5 °C for 24 h was optimal for patients who received an anesthesia block and at 5 °C for 16 h or at 10 °C for 24 h for those who did not receive the anesthesia block. These results can be used as a reference for setting the temperature and duration of cryotherapy after arthroscopic shoulder surgery.

Fixation of an Osteochondral Lesion of the Femoral Intercondylar Groove Using Autogenous Osteochondral Grafts and Bioabsorbable Pins in a Patient with Open Physes: A Case Report.

Osteochondral lesion (OCL) of the patellofemoral (PF) joint is not an uncommon cause of knee pain, and surgery is needed when conservative treatment fails. However, there is a lack of evidence regarding the optimal surgical treatment for OCL of the PF joint. Fixation of OCLs using autogenous osteochondral grafts has been reported to be effective for OCL of the knee. However, in this surgical technique, the biomechanical strength of osteochondral grafts may not be sufficient in patients with open physes due to the specific quality of the cartilage and subchondral bone given their age. There is a lack of studies reporting fixation of the OCL located in the PF joint using autogenous osteochondral grafts. We herein report a case of OCL of the femoral intercondylar groove where autogenous osteochondral grafts augmented with bioabsorbable pins were used to fix the lesion in a 14-year-old patient with open physes. Preoperative MRI revealed a completely detached OCL of the intercondylar groove (36 mm × 20 mm). Although a total of four osteochondral grafts were harvested from the non-weightbearing area of the lateral femoral condyle, cartilage detached from one of the grafts. The quality of the osteochondral grafts was considered to be insufficient for stabilization of the OCL; thus, two bioabsorbable pins were additionally inserted following fixation of the lesion using three osteochondral grafts. After two years of follow-up, postoperative functional scores were favorable without knee pain. The present case suggests that fixation of the OCL using autogenous osteochondral grafts may not be appropriate for young patients with open physes.

EPLINß Is Involved in the Assembly of Cadherin-catenin Complexes in Osteoblasts and Affects Bone Formation.

Epithelial protein lost in neoplasm (EPLIN) is an actin-associated cytoskeletal protein that plays an important role in epithelial cell adhesion. EPLIN has two isoforms: EPLINα and EPLINß. In this study, we investigated the role of EPLINß in osteoblasts using EPLINß-deficient (EPLINßGT/GT ) mice. The skeletal phenotype of EPLINßGT/GT mice is indistinguishable from the wildtype (WT), but bone properties and strength were significantly decreased compared with WT littermates. Histomorphological analysis revealed altered organization of bone spicules and osteoblast cell arrangement, and decreased alkaline phosphatase activity in EPLINßGT/GT mouse bones. Transmission electron microscopy revealed wider intercellular spaces between osteoblasts in EPLINßGT/GT mice, suggesting aberrant cell adhesion. In EPLINßGT/GT osteoblasts, α- and ß-catenins and F-actin were observed at the cell membrane, but OB-cadherin was localized at the perinuclear region, indicating that cadherin-catenin complexes were not formed. EPLINß knockdown in MC3T3-e1 osteoblast cells showed similar results as in calvaria cell cultures. Bone formation markers, such as RUNX2, Osterix, ALP, and Col1a1 mRNA were reduced in EPLINß knockdown cells, suggesting an important role for EPLINß in osteoblast formation. In conclusion, we propose that EPLINß is involved in the assembly of cadherin-catenin complexes in osteoblasts and affects bone formation.

A longer duration from injury to surgery is associated with preoperative deterioration of an isolated meniscal tear in patients aged 40 years or older.

PURPOSE: To evaluate the preoperative deterioration of an isolated meniscal tear in patients aged 40 years or older, and whether time from injury to surgery is associated with worsening of a meniscal tear. METHODS: Patients aged 40 years or older who underwent arthroscopic surgery for isolated meniscal tear between 2014 and 2019 were retrospectively reviewed. The diagnostic magnetic resonance imaging (MRI) findings and arthroscopic findings were compared to evaluate the deterioration of meniscal tears. Predictors of the development of meniscal tears; patient demographic factors, duration from injury to surgery (injury to MRI and MRI to surgery), and image findings were assessed. RESULTS: A total of 58 patients (58 knees) were included (mean age, 55.9 ± 8.5 years; male/female, 31/27). An isolated meniscal tear deteriorated in 28 (48.3%). Compared patients with and without deteriorated meniscal tear, significant differences were found in the MRI grade of meniscal tear (p = 0.03), duration from injury to MRI (164.2 ± 167.9 vs 45.2 ± 48.7 days, p < 0.001), and from MRI to surgery (148.8 ± 91.1 vs 67.6 ± 56.7 days, p < 0.001). A multivariate regression analysis showed that the duration from injury to MRI (odds ratio [OR], 1.03; p < 0.001) and from MRI to surgery (OR, 1.02; p < 0.001) were independent predictors. CONCLUSION: Approximately 50% of isolated meniscal tears deteriorated preoperatively in patients aged 40 years or older. The duration from injury to surgery was an independent predictor of worsening of an isolated meniscal tear.

Angiotensin II Induces Aortic Rupture and Dissection in Osteoprotegerin-Deficient Mice.

Background The biological mechanism of action for osteoprotegerin, a soluble decoy receptor for the receptor activator of nuclear factor-kappa B ligand in the vascular structure, has not been elucidated. The study aim was to determine if osteoprotegerin affects aortic structural integrity in angiotensin II (Ang II)-induced hypertension. Methods and Results Mortality was higher (P<0.0001 by log-rank test) in 8-week-old male homozygotes of osteoprotegerin gene-knockout mice given subcutaneous administration of Ang II for 28 days, with an incidence of 21% fatal aortic rupture and 23% aortic dissection, than in age-matched wild-type mice. Ang II-infused aorta of wild-type mice showed that osteoprotegerin immunoreactivity was present with proteoglycan. The absence of osteoprotegerin was associated with decreased medial and adventitial thickness and increased numbers of elastin breaks as well as with increased periostin expression and soluble receptor activator of nuclear factor-kappa B ligand concentrations. PEGylated human recombinant osteoprotegerin administration decreased all-cause mortality (P<0.001 by log-rank test), the incidence of fatal aortic rupture (P=0.08), and aortic dissection (P<0.001) with decreasing numbers of elastin breaks, periostin expressions, and soluble receptor activator of nuclear factor-kappa B ligand concentrations in Ang II-infused osteoprotegerin gene-knockout mice. Conclusions These data suggest that osteoprotegerin protects against aortic rupture and dissection in Ang II-induced hypertension by inhibiting receptor activator of nuclear factor-kappa B ligand activity and periostin expression.

Biomechanical effect of metal augment and bone graft on cup stability for acetabular reconstruction of total hip arthroplasty in hip dysplasia: a finite element analysis.

BACKGROUND: Different methods of acetabular reconstruction with total hip arthroplasty (THA) for Crowe II and III of adult developmental dysplasia of the hip (DDH) acetabular bone defect have been implemented clinically. However, the biomechanical effect of different augmented materials for acetabular reconstruction in THA on shell stability has never been discussed. METHODS: In the present study, autologous bone graft (BG)and metal (Ti6Al4V) augment (MA) were simulated with several acetabular bone defect models of DDH in THA. The contact pressure and micromotion between the shell and host bone were measured for evaluating the shell stability using a finite element method. RESULTS: The peak contact stress between shell and host bone was higher in the MA situation (12.45 vs 8.71 MPa). And the load transfer path was different, for BG models, the high local contact stresses were found at the junction of bone graft and host bone while for MA models the concentrated contact stresses were at the surface of MA. The peak relative micromotion between shell and host bone was higher in the MA situation (12.61 vs 11.13 µm). However, the peak micromotion decreased in the contact interface of MA and cup compared to the BG models. CONCLUSIONS: The higher micromotion was found in MA models, however, enough for bone ingrowth, and direct stronger fixation was achieved in the MA-cup interface. Thus, we recommended the MA can be used as an option, even for Crowe III, however, the decision should be made from clinical follow-up results.

Crucial role of high-mobility group box 2 in mouse ovarian follicular development through estrogen receptor beta.

High-mobility group box 2 (HMGB2) is a chromatin-associated protein that is an important regulator of gene transcription, recombination, and repair processes. The functional importance of HMGB2 has been reported in various organs, including the testis, heart, and cartilage. However, its role in the ovary is largely unknown. In this study, ovary tissues from wild-type (WT) and HMGB2-knock-out (KO) mice were examined by histopathological staining and immunohistochemistry. The ovary size and weight were significantly lower in HMGB2-KO mice than in age-matched WT littermates. Histopathological analysis revealed ovarian atrophy and progressive fibrosis in 10-month-old HMGB2-KO mouse ovaries. Compared to age-matched WT mice, the numbers of oocytes and developing follicles were significantly decreased at 2 months of age and were completely depleted at 10 months of age in HMGB2-KO mice. Immunohistochemistry revealed the expression of HMGB2 in the granulosa cells of developing follicles, oocytes, some corpora lutea, and stromal cells. Importantly, HMGB2-positive cells were co-localized with estrogen receptor beta (ERß), but not ERα. Estrogen response element-binding activity was demonstrated by southwestern histochemistry, and it was decreased in HMGB2-KO mouse ovaries. Cell proliferation activity was also decreased in HMGB2-KO mouse ovaries in parallel with the decreased folliculogenesis. These results indicated that the depletion of HMGB2 induced ovarian atrophy that was characterized by a decreased ovarian size and weight, progressive fibrosis, as well as decreased oocytes and folliculogenesis. In conclusion, we demonstrated the crucial role of HMGB2 in mouse ovarian folliculogenesis through ERß expression.