17ß-Estradiol attenuates inflammation and tendon degeneration in a rat model of Achilles tendinitis.

INTRODUCTION: 17ß-Estradiol (E2) is an immune-regulatory agent with anti-inflammatory effects. However, it is still unknown whether E2 exerts pharmacological properties against Achilles tendinitis (AT). This study aims to investigate the effects of E2 on AT and its underlying mechanisms. MATERIALS AND METHODS: The established model of Achilles tendinitis was intraperitoneally injected with E2 (10, 20, or 30 µg/kg/d). After 8 weeks, biomechanical properties of the Achilles tendon were determined. Hydroxyproline content and tendon degeneration-related biomarkers were determined. The levels of inflammatory cytokines and apoptotic-related biomarkers in tendon tissues were determined. Furthermore, western blotting was determined to detect the expressions of ER-α and the PI3K/Akt pathway in tendon tissues. RESULTS: E2 relieved AT-related symptoms in a dose-dependent manner. E2 ameliorated tendon degeneration by regulating tendon degeneration-related biomarkers (e.g. collagen types I and III, Decorin (DCN), and tenascin-C). Besides, treatment with E2 suppressed inflammatory cytokines and increased anti-inflammatory cytokines. Treatment with E2 also regulated cell apoptosis in tendon tissues. The underlying mechanism study revealed that treatment with E2 activated ER-α and upregulated the PI3K/Akt pathway. CONCLUSION: The regulatory effects of E2 on inflammation and tendon degeneration in a rat model of AT were associated with the ER-α and the PI3K/Akt signaling pathways.

MicroRNA-199-3p up-regulation enhances chondrocyte proliferation and inhibits apoptosis in knee osteoarthritis via DNMT3A repression.

AIM: Studies have pivoted on the position of microRNAs (miRNAs) in knee osteoarthritis (KOA) but not the more specific function of miR-199-3p. Thus, this study is to uncover the mechanism of miR-199-3p in KOA. METHODS: Rats KOA models were established by modified Hulth method. miR-199-3p expression was observed in cartilage of KOA rats. The binding sites of miR-199-3p were predicted by bioinformatics analysis and the potential interaction between DNA methyltransferase 3A (DNMT3A) and miR-199-3p was verified by dual-luciferase reporter gene assay. Rats were injected with miR-199-3p agomir or antagomir and DNMT3A siRNA into the knee joint. Inflammatory response factors in serum and cartilage tissues, cell apoptosis, and pathological status of cartilage tissues were detected. Chondrocytes were isolated from KOA cartilages and treated with miR-199-3p mimic or inhibitor and DNMT3A siRNA. Chondrocyte proliferation and apoptosis were detected. RESULTS: miR-199-3p expression was suppressed in cartilage of KOA rats. Dual-luciferase reporter gene assay proved that a miR-199-3p-binding site was located in the 3'UTR of DNMT3A mRNA. Inflammation, chondrocyte apoptosis and cartilage pathological changes were improved by miR-199-3p agomir but aggravated by miR-199-3p antagomir. The effects of miR-199-3p antagomir on KOA rats were partially reversed by DNMT3A siRNA. miR-199-3p mimic or DNMT3A siRNA decreased KOA chondrocytes apoptosis and promoted proliferation. miR-199-3p inhibitor showed the opposite functions to miR-199-3p mimic. The effects of miR-199-3p inhibitor on chondrocytes were reversed by DNMT3A siRNA. CONCLUSION: This study highlights that miR-199-3p up-regulation or down-regulation of DNMT3A induces chondrocyte proliferation and inhibits apoptosis in KOA, which may widen our eyes to treat patients with KOA.

Finite element analyses of three minimally invasive fixation techniques for treating Sanders type II intra-articular calcaneal fractures.

BACKGROUND AND OBJECTIVE: Calcaneal Sanders type II or III fractures are highly disabling with significant burden. Surgical treatment modalities include open reduction and internal fixation (ORIF) techniques and a variety of minimally invasive surgical (MIS) approaches. ORIF techniques are associated with complications and traditional MIS techniques need extensive intraoperative fluoroscopic procedures. The present study aims to investigate the effects of three different minimally invasive internal fixation (MIIF) techniques used to treat Sanders type II intra-articular calcaneal fractures using finite element analyses. METHODS: A 64-row spiral computed tomography scan was used to observe the calcaneus of a healthy adult. The scanning data were imported into Mimics in a DICOM format. Using a new model of a Sanders type II-B intra-articular calcaneal fracture, three minimally invasive techniques were simulated. Technique A involved fixation using an isolated minimally invasive locking plate; Technique B used a minimally invasive locking plate with one medial support screw; and Technique C simulated a screw fixation technique using four 4.0-mm screws. After simulating a 640-N load on the subtalar facet, the maximum displacement and von Mises stress of fragments and implants were recorded to evaluate the biomechanical stability of different fixation techniques using finite element analyses. RESULTS: After stress loading, the maximum displacements of the fragments and implants were located at the sustentaculum tali and the tip of sustentaculum tali screw, respectively, in the three techniques; however, among the three techniques, Technique B had better results for displacement of both. The maximum von Mises stress on the fragments was < 56 Mpa, and stress on the implants using the three techniques was less than the yield strength, with Technique C having the least stress. CONCLUSION: All three techniques were successful in providing a stable fixation for Sanders type II intra-articular calcaneal fractures, while the minimally invasive calcaneal locking plate with medial support screw fixation approach exhibited greater stability, leading to improved enhancement for the facet fragment; however, screw fixation dispersed the stress more effectively than the other two techniques.

Risk factors for chronic ankle instability after first episode of lateral ankle sprain: A retrospective analysis of 362 cases.

BACKGROUND: Chronic ankle instability (CAI) is a common sequela following an acute lateral ankle sprain (LAS). To treat an acute LAS more effectively and efficiently, it is important to identify patients at substantial risk for developing CAI. This study identifies magnetic resonance imaging (MRI) manifestations for predicting CAI development after a first episode of LAS and explores appropriate clinical indications for ordering MRI scans for these patients. METHODS: All patients with a first-episode LAS who received plain radiograph and MRI scanning within the first 2 weeks after LAS from December 1, 2017 to December 1, 2019 were identified. Data were collected using the Cumberland Ankle Instability Tool at final follow-up. Demographic and other related clinical variables, including age, sex, body mass index, and treatment were also recorded. Univariable and multivariable analyses were performed successively to identify risk factors for CAI after first-episode LAS. RESULTS: A total 131 out of 362 patients with a mean follow-up of 3.0 ± 0.6 years (mean ± SD; 2.0-4.1 years) developed CAI after first-episode LAS. According to multivariable regression, development of CAI after first-episode LAS was associated with 5 prognostic factors: age (odds ratio (OR) = 0.96, 95% confidence interval (95%CI): 0.93-1.00, p = 0.032); body mass index (OR = 1.09, 95%CI: 1.02-1.17, p = 0.009); posterior talofibular ligament injury (OR = 2.17, 95%CI: 1.05-4.48, p = 0.035); large bone marrow lesion of the talus (OR = 2.69, 95%CI: 1.30-5.58, p = 0.008), and Grade 2 effusion of the tibiotalar joint (OR = 2.61, 95%CI: 1.39-4.89, p = 0.003). When patients had at least 1 positive clinical finding in the 10-m walk test, anterior drawer test, or inversion tilt test, they had a 90.2% sensitivity and 77.4% specificity in terms of detecting at least 1 prognostic factor by MRI. CONCLUSION: MRI scanning is valuable in predicting CAI after first-episode LAS for those patients with at least 1 positive clinical finding in the 10-m walk test, anterior drawer test, and inversion tilt test. Further prospective and large-scale studies are necessary for validation.

Lateral approach for insertional Achilles tendinitis with Haglund deformity.

Objective: The study aims to investigate the functional outcome of the lateral approach for insertional Achilles tendinitis (IAT) with Haglund deformity. Methods: From January 2016 to September 2019, 14 cases of IAT with Haglund deformity that resisted conservative treatment received surgery in our department. A lateral approach was used to debride the bony and soft tissue and reattach the insertion of the Achilles tendon. The Visual Analog Scale (VAS), American Orthopedic Foot and Ankle Score (AOFAS), and Victorian Institute of Sport Tendon Study Group-Achilles Tendinopathy score (VISA-A) were used to evaluate clinical outcomes. Result: The mean patient age was 39.57 years at the time of surgery. The mean follow-up was 14.74 months. The mean VAS score significantly decreased from 4.86 ± 0.86 preoperatively to 1.21 ± 1.58 postoperatively (P < 0.001). The mean AOFAS score significantly improved from 66.64 ± 6.23 preoperatively to 90.21 ± 11.50 postoperatively (P < 0.001). The mean preoperative and the last follow-up VISA-A were 66 (range 56.75-69.25) and 86 (range 75.75-97.00) points, respectively (P < 0.05). Conclusion: The lateral approach was effective and safe for IAT with Haglund deformity. Moreover, the mid-term functional outcome was promising. Level of Clinical Evidence: IV.

Robot-assisted percutaneous screw fixation in the treatment of navicular fracture.

Background: Long recovery time, large scar, postoperative swelling and pain are possible side effects of open reduction internal fixation (ORIF) for tarsal navicular fractures. Early exercise instruction is made possible by the use of an intraoperative robot-assisted percutaneous invasive closed reduction internal fixation. The goal of the trial was to determine whether percutaneous screw internal fixation with robot assistance might be used to treat navicular fractures. Methods: 27 patients with navicular fractures had surgical treatment between June 2019 and December 2021. Of those, 20 instances were treated with ORIF, while 7 cases had robot-assisted percutaneous screw internal fixation. At the final follow-up, the American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot score and the visual analogue scale (VAS) score were compared to determine outcomes and function. Results: Follow-up was obtained in all 27 patients after surgery, with a mean follow-up time of 21.81 months, ranging from 15 to 29 months . In the 7 instances of robot-assisted group, percutaneous guide wire insertion and screw placement only needed one attempt and the depth and position of the implant were both satisfactory. In the ORIF group, there were two patients who sustained cutaneous nerve injuries. The AOFAS score and the VAS score of the group receiving robot-assisted navigation percutaneous screw fixation were 92.25 ± 2.22 and 0.75 ± 0.25 respectively at the last follow-up, while 82.25 ± 7.15 and 0.50 ± 0.29 were the respective values for the ORIF group. Conclusion: Intraoperative robot-assisted percutaneous closed reduction internal fixation for tarsal navicular fractures can accomplish exact localization of fracture site, reduce soft tissue damage and operative time. According to current view, this method offers fewer complications, a faster recovery after surgery, and more patient satisfaction.

[Arthroscopic treatment of ankle instability combined with anteromedial impingement syndrome].

OBJECTIVE: To investigate the surgical skills and clinical curative results of arthroscopic treatment of ankle instability combined with anteromedial impingement syndrome. METHODS: From February 2019 to August 2020, 13 patients with ankle instability combined with anteromedial impingement were retrospectively analyzed. There were 10 males and 3 females with age of (40.0±15.1) years old. The course of disease was(44.1±33.2) months. All patients had history of ankle sprain. MRI showed the injury of anterior talofibular ligament. All patients had anteromedial pain and pressing pain when ankle dorsiflexion. All patients were treated with ankle debridement and Brostr?m-Gould surgery under ankle arthroscopic. Postoperative results were evaluated by VAS(visual analogue scale) and AOFAS-AH(American Orthopaedic Foot and Ankle Society Ankle-Hindfoot scale, AOFAS-AH). RESULTS: All 13 patients completed the surgery successfully with an operative time of 60 to 90 minutes. All the surgical incisions healed by first intention, and no complications such as incision infection, skin necrosis and neurovascular injury. Follow-up time was (18.1±4.7) months. At the latest follow-up, the VAS score was 1.2±1.1, which was significantly lower than the preoperative score 4.8±1.5 (P<0.05);the AOFAS-AH score 94.2±5.1 was significantly higher than the preoperative score 65.5±11.5 (P<0.05). The AOFAS-AH score at the final follow-up ranged from 84 to 100. All patients walked with normal gait without ankle instability or impingement recurrence. CONCLUSION: Ankle anteromedial impingement syndrome combined with ankle instability is easy to be ignored clinically. Such kind of anteromedial impingement syndrome is mostly related to osteophyte at dorsal medial talar neck. Arthroscopic treatment of ankle instability combined with anteromedial impingement syndrome has satisfactory curative effect with safety and minimal injury.

[Early efficacy analysis of minimally invasive Chevron-Akin osteotomy for the treatment of mild to moderate hallus valgus].

OBJECTIVE: To explore early efficacy of minimally invasive Chevron Akin(MICA) osteotomy for the treatment of mild to moderate hallux valgus. METHODS: From June 2019 to April 2021, a total of 26 patients (29 feet) with mild to moderate hallux valgus, including 1 male and 25 females aged from 19 to 78 years old with an average of(38.3±19.5) years old, were treated with MICA. Preoperative and postoperative hallux valgus angle(HVA), intermetatarsal angle(IMA) and shortening of the first metatarsal were observed and compared. American Orthopedic Foot and Ankle Society (AOFAS) forefoot scoring system and visual analogue scale (VAS) were applied to evaluate clinical outcome at the final follow-up, and complications were also recorded. RESULTS: All patients obtained followed up from 12 to 33 months with an average of(19.6±5.1) months. HVA and IMA was improved from (32.3±6.6)° and (11.7±3.2)° pre-operatively to (13.0±5.3)° and (6.1±3.2)° post-operatively, respectively, which had a significant difference (P<0.01). The average shortening of the first metatarsal was (2.7±1.1) mm. AOFAS and VAS was improved from (55.7±7.4) and (6.5±1.5) preoperatively and to (88.5±7.9) and (0.7±0.4) respectively at the final follow-up, which also had a significant difference(P<0.01). According to AOFAS score, 15 feet achieved an excellent result, 11 good and 3 moderate. CONCLUSION: MICA osteotomy is a safe and reliable surgical technique for mild to moderate hallux valgus with advantages of minimally invasive, rapid recovery, low complication rate and an effect improvement of hallux valgus deformity.

[Modified anterolateral thigh perforator flap pedicled by cross-bridge microvascular anastomosis for repairing soft tissue defects in middle and lower segments of leg].

Objective: To explore the effectiveness of modified anterolateral thigh perforator flap pedicled by cross-bridge microvascular anastomosis in treatment of soft tissue defects in the middle and lower segments of the leg. Methods: Between March 2011 and June 2015, 15 cases with skin and soft tissue defects in the middle and lower segments of the legs were treated. There were 9 males and 6 females, aged 22-48 years (mean, 32.6 years). Of whom, 8 patients caused by traffic accidents, 5 by machine twist, and 2 by crash injury of heavy object. The mean interval from injury to admission was 82.6 hours (range, 2 hours to 1 week). The area of defect ranged from 13 cm×9 cm to 23 cm×16 cm. After primary debridement and vaccum sealing drainage treatment, the defects were repaired with modified anterolateral thigh perforator flap pedicled by cross-bridge microvascular anastomosis. The size of flap ranged from 15 cm×10 cm to 25 cm×15 cm. The donor sites were sutured directly or repaired with the skin grafts. The pedicle division was done at 4 weeks after operation. Results: After operation, venous crisis occurred in 1 case and distal skin necrosis in 2 cases which was healed by dressing change. The other tissue flaps survived successfully and wounds healed by first intention. All skin grafts at donor site survived after operation, and primary healing of wound was obtained. All patients were followed up 6-24 months (mean, 13 months). All flaps were characterized by soft texture, satisfactory appearance, and restoring the protective sensation. Moreover, the two-point discrimination ranged from 15 to 28 mm (mean, 19.5 mm) at 6 months after operation. The function of both lower extremities were normal without obvious contracture of scar at donor site. Conclusion: Modified free anterolateral thigh perforator flap, with little damage in donor site, a reliable blood supply by making a cross-bridge microvascular anastomosis with pretibial or posterior tibial blood vessel on normal leg, is a reliable alternative method for repairing soft tissue defects with the main vessels of serious injury in the middle and lower segments of the leg.