Comparison of the operation safety and biomechanical stability of sacral alar-iliac vs. sacroiliac screws in the fixation of sacroiliac joint in simulated models of low bone density.

BACKGROUND: Sacral alar-iliac screws (SAISs) have been used for sacroiliac joint and are superiority to traditional sacroiliac screws (SISs) in patients with low bone density. The aim of this study was to investigate the operation safety and biomechanical stability of the SIS, transsacral-transiliac screw (TSTIS), S1AIS and S2AIS in the treatment of sacroiliac joint in simulated models of low bone density. METHODS: CT data from 80 normal pelvic structures were employed to measure the anatomical parameters, including the safety zones of the S1AIS and S2AIS at the insertion point and the trajectory lengths of the SIS, TSTIS, S1AIS and S2AIS. Sixteen synthetic pelvises with simulated osteoporotic bone structure were used to simulate type C Tile lesions and divided into 4 groups with an anterior plate and posterior fixation using one of the following: 1) one SIS on each side, 2) one TSTIS fixing both sides, 3) one S1AIS on each side, or 4) one S2AIS on each side. The stiffness and maximum load of the specimens were analyzed using a biomechanical machine under vertical loading. RESULTS: The safety zone of S1AIS was larger than that of S2AIS (p < 0.05). The TSTIS had the largest trajectory length, followed by the S1AIS and S2AIS, and the SIS had the smallest trajectory length (p < 0.05). However, the lengths of the TSTIS (26.1 ± 1.7 mm) and SIS (27.8 ± 1.8 mm) trajectories on the short side (the iliac side) were smaller than those of S1AIS (40.4 ± 3.8 mm) and S2AIS (39.1 ± 3.8 mm), thus indicating significant differences (p < 0.05). The stiffness and maximum load of S1AIS and S2AIS were similar and the greatest, followed by TSTIS and SIS (p < 0.05). CONCLUSION: The stability of S1AIS and S2AIS is similar, both stronger than that of SIS and TSTIS, which have shorter lengths of the screw trajectories on the ilium side. However, the safety zone of S2AIS at the insertion point is smaller than that of S1AIS. Therefore, considering both safety and stability, S1AIS is the preferred choice for fixation of sacroiliac joint dislocation in simulated models of low bone density.

Radiological evaluation of effectiveness of PCCP fixation for femoral neck fracture: med-term effectiveness in a retrospective multicenter.

Background It has been reported in the literature that the complication rate of percutaneous compression plate (PCCP) is the lowest among the new internal fixators for the treatment of femoral neck fracture (FNS). However, no multicenter studies of PCCP for FNS have been reported. This study aimed to evaluate the med-term effectiveness of PCCP in a multicenter mainly through radiology. Methods 265 patients with FNF treated with PCCP fixation in our five hospitals between January 2011 and December 2020 were retrospectively analyzed. 140 men and 125 women; aged 19-79 (mean 51.6）years. The follow-up time was 2-5 years (mean 3.1). Radiological evaluation of the therapeutic effect was the main outcome, and the function was the secondary outcome. Results One case of screw cutting out, 3 cases of screw back out, 25 cases of neck shortening, 2 cases of nonunion, 8 cases of delayed healing, and 29 cases of avascular necrosis (AVN). Bivariate correlation showed that shortening healing was correlated with age, Singh index, and Garden alignment index, poor healing was correlated with garden alignment index, and AVN was correlated with Pauwels and Garden classifications and operation timing. Further pairwise comparison analysis showed that age of > 65 and Singh index IV were dangerous factors for neck shortening, and the operation timing > 3 days, Pauwels II and III, and Garden III and IV were dangerous factors for AVN. The excellent and good rate of function in 198 patients who were readmitted for internal fixator removal or other surgery was 90.9%. Conclusion PCCP for FNS has satisfactory med-term efficacy with a low complication rate. The main complication is AVN, which is prone to occur in patients with displaced Pauwels II or III FNF and operation timing > 3 days. Another main complication is shortening healing, which is prone to occur in patients with an age of > 65 and Singh index IV.

Relevance of vitamin D on NAFLD and liver fibrosis detected by vibration controlled transient elastography in US adults: a cross-sectional analysis of NHANES 2017-2018.

BACKGROUND: The connection between vitamin D to non-alcoholic fatty liver disease (NAFLD) is still unclear. Herein, the relationship of vitamin D with NAFLD and liver fibrosis (LF) detected by vibration controlled transient elastography was investigated in US adults. METHODS: The National Health and Nutrition Examination Survey of 2017-2018 was employed for our analysis. Participants were categorized as having either vitamin D deficiency (<50 nmol/L) or vitamin D sufficiency (≥50 nmol/L). A controlled attenuation parameter score of ≥ 263 dB/m was employed to define NAFLD. Significant LF was identified by the liver stiffness measurement value of ≥ 7.9 kPa. Multivariate logistic regression was adopted to explore the relationships. RESULTS: Among the 3407 participants, the prevalence of NAFLD and LF was 49.63% and 15.93% respectively. Compared to participants without NAFLD, no significant difference in serum vitamin D was observed in NALFD participants (74.26 vs. 72.24 nmol/L; p = 0.21). Using multivariate logistic regression analysis, no obvious connection of vitamin D status to NAFLD (sufficiency vs. deficiency, OR 0.89, 95%CI 0.70-1.13) was discovered. However, among NAFLD participants, the sufficiency of vitamin D represents a lower LF risk (OR 0.56, 95%CI 0.38-0.83). When evaluated in quartiles, in comparison to the lowest quartile, high vitamin D represents low LF risk in a dose-dependent manner (Q2 vs. Q1, OR 0.65, 95%CI 0.37-1.14; Q3 vs. Q1, OR 0.64, 95%CI 0.41-1.00; Q4 vs. Q1, OR 0.49, 95%CI 0.30-0.79). CONCLUSIONS: No relationship was found between vitamin D and CAP-defined NAFLD. However, a positive connection of the high serum vitamin D to the reduced LF risk was found among NAFLD subjects.Key messages:Our study found no relationship between vitamin D and CAP-defined NAFLD in US adults.High serum vitamin D was inversely associated with liver fibrosis in a dose-dependent manner among NAFLD participants.

A novel modified McLaughlin surgery for treating locked chronic posterior shoulder dislocation.

BACKGROUND: Posterior shoulder dislocation is an uncommon orthopaedics injury and is frequently missed or misdiagnosed, accounting for 2%-4% of all shoulder dislocations, and is associated with the reverse Hill-Sachs lesion. Once posterior shoulder dislocation develops into a chronic disease, it will bring a lot of trouble to the treatment, especially in repairing the humeral defects. Surgical strategies are also developing and innovating to deal with this injury, including transfer of subscapularis tendon or lesser tubercle, humeral rotational osteotomy, autogenous bone graft or allograft. Shoulder replacement seems to be the ultimate and only option when the injury becomes irreparable, although some studies have shown unsatisfactory follow-up results. Considering no gold-standard treatment for locked posterior shoulder dislocation, we described a novel modified McLaughlin procedure for locked chronic posterior shoulder dislocation and evaluated the functional outcomes. METHODS: This study included five locked chronic posterior shoulder dislocation patients with an associated reverse Hill-Sachs lesion, in which the compression surface covered 30-40% of the humeral head. The mean period from injury to receiving surgery was 11.6 weeks (6-24 weeks). All five patients underwent the modified McLaughlin procedure, mainly divided into three steps, including open reduction, transfer of the partial lesser tuberosity and artificial bone to repair the reverse Hill-Sachs defects. The kernel technique was to fix the transferred tuberosity with two lag screws and strengthen it with two Ethibond sutures. The Constant-Murley score (CMS), the range of shoulder motion and the complications were recorded to assess and compare the functional situation of the shoulder postoperatively and postoperatively. RESULTS: After an average of 19.8 months (12-30) of follow-up, the mean CMS improved to 85.8 ± 4.9 (79-91) compared with 46.0 ± 4.5 (40-52) preoperatively, which showed a significant difference (p = 0.001). In the final follow-up, all five patients showed no symptoms of shoulder instability, and there was no pain or limited activity in daily life, thus all patients were satisfied with the results. CONCLUSION: Repairing the reverse Hill-Sachs lesion by transferring the partial lesser tuberosity combined with artificial bone fixed by lag screws and sutures can ensure shoulder stability and provide pain relief and good function in patients with locked chronic posterior shoulder dislocation associated with the humeral head defect.

[Study of characteristics and treatment of "kissing fracture" of humeroradial joint].

Objective: To explore the clinical characteristics and treatment of "kissing fracture" of humeroradial joint. Methods: A clinical data of 12 patients with "kissing fracture" of the humeroradial joint between January 2016 and June 2021 was retrospectively analyzed. There were 8 males and 4 females with an average age of 41.9 years (range, 15-75 years). The fractures caused by falling in 7 cases, by falling from height in 3 cases, and by sports in 2 cases. The time from injury to admission was 2-72 hours (median, 2 hours). According to Mason's classification, the radial head fractures were rated as type Ⅰ in 2 cases, type Ⅱ in 8 cases, and type Ⅲ in 2 cases. According to Grantham's classification, the humeral capitulum fractures were rated as type Ⅰ in 10 cases and type Ⅱ in 2 cases. Among them, 4 cases of Grantham type Ⅰ humeral capitulum fracture were missed by X-ray film and confirmed by CT and/or MRI. Four cases were complicated with other injuries of elbow joint. The radial head fractures were fixed with screws or mini plate in 11 cases and treated conservatively in 1 case; the humeral capitulum fractures were fixed with screw or plate in 9 cases, removed in 1 case, and treated conservatively in 2 cases. X-ray film was used to evaluate the fracture healing; Mayo Elbow Performance Score (MEPS) was used to evaluate the functional recovery of the affected limb, and the range of motion (ROM) of the elbow joint of the affected limb was detected. Results: All the incisions healed by first intention without early complications. All patients were followed up 10-24 months, with an average of 15.2 months. X-ray films showed that all fractures healed, and the healing time was 2-3 months, with an average of 2.3 months. At last follow-up, the ROM of flexion-extension of the elbow joint was 65°-161°, with an average of 136.9°; the ROM of rotation was 70°-180°, with an average of 149.2°. MEPS ranged from 70 to 100, with an average of 87.4; 8 cases were excellent, 2 cases were good, and 2 cases were fair; the excellent and good rate was 83.3%. Conclusion: The "kissing fracture" of the humeroradial joint is relatively rare, and the humeral capitulum fracture is milder than radial head fracture. X-ray examination alone can easily miss the diagnosis of Grantham type Ⅰ humeral capitulum fracture. The "kissing fracture" of the humeroradial joint is treated according to the principle of intra-articular fracture, and the good effectiveness can obtain.

A novel minimally invasive broken nail extractor for cannulated intramedullary nails: Trial and application in a few cases.

Successful and minimally invasive extraction of a broken distal end of an intramedullary nail is challenging. This study introduces a simple and reproducible technique for the extraction of broken cannulated intramedullary nails using a novel minimally invasive broken nail extractor. Five amputated adult lower-leg specimens were used to create models of the broken distal end of the cannulated intramedullary nails remaining in the medullary cavity of the distal tibia. Two orthopedic resident physicians with experience in tibial intramedullary nail implantation were selected to blindly extract the broken intramedullary nail using the novel minimally invasive broken nail extractor. The extraction outcome was assessed. The broken nail extractor was applied to 3 patients with broken intramedullary nails remaining in the medullary cavity of the distal tibia. In the lower-leg specimens, the extraction success rate was 100%, the median number of extraction times was 1.9 (range 1-3.5), and the median duration of extraction was 38 s (range 20-52 s). All the broken intramedullary nails in the 3 patients were successfully extracted without complications related to the surgery. The study shows that our technique is simple, reproducible, and has a high extraction success rate, but more case applications are needed to verify its effect.

Radio-anatomical study of anterior-posterior placement sacroiliac screw channel.

PURPOSE: The outlet of the classic sacroiliac screw (SIS) cannot be precisely controlled by aiming devices, which may lead to malpositioned implants and neurovascular and visceral injury. This study aimed to radio-anatomically measure the parameters of the channel for anterior-posterior placement SIS (AP-SIS), which can be placed percutaneously with an aiming device. METHODS: Pelvic CT scan data of 80 healthy adults (40 males and 40 females) with an average age of 45 years (range 20-70 years) were collected. The length (L), width (W), height (H), cortical bone spacing (M), camber angle (E), anteversion angle (F), cross-sectional safety angle (P) and sagittal safety angle (Q) of the channel were measured by CT or Mimics software. RESULTS: The L, W, H, M, E, F, P and Q measures of S1 were 109.2 ± 8.0 mm, 18.5 ± 1.9 mm, 21.7 ± 1.7 mm, 8.1 ± 0.4 mm, 44.2 ± 3.2°, 42.4 ± 3.6°, 16.8 ± 1.1°, and 19.4 ± 2.0°, respectively, for S1, and 113.5 ± 9.4 mm, 18.2 ± 1.5 mm, 21.7 ± 1.7 mm, 7.7 ± 0.4 mm, 44.7 ± 3.2°, 31.2 ± 2.7°, 13.8 ± 1.0° and 15.4 ± 1.4°, respectively, for S2. Of the L measures, the intra-iliac segment was slightly longer than the intra-sacral segment. All parameters showed significant sex-related differences (p < 0.05). CONCLUSION: The AP-SIS channels of S1-2 have sufficient width and length to accommodate a cancellous screw with a Φ 7.0-8.0 mm and a length 90-130 mm. The intra-iliac segment is a long channel screw with better mechanical properties over classic SIS.

[Self-made dentation hook plate associated with hot-air balloon technique on treatment of Mutch â or â ¡ type isolated greater tuberosity fractures of humerus].

OBJECTIVE: To observe effectivness and safeness of self-made dentation hook plate associated with hot-air balloon technique in treating Mutch Ⅰ or Ⅱ type isolated greater tuberosity fractures of humerus. METHODS: Between January 2016 and December 2018, 15 patients with Mutch Ⅰ or Ⅱ type greater tuberosity fractures were treated with self-made dentation hook plate associated with hot-air balloon technique. There were 9 males and 6 females with an average age of 45.1 years (range, 29-62 years). The injury causes included falling injury in 9 patients and traffic accident injury in 6 patients. According to Mutch classification, 4 cases were MutchⅠ type and 11 cases were Mutch Ⅱ type. There were 7 cases with anterior dislocation of shoulder. The time from injury to operation was 2-10 days (mean, 4.5 days). RESULTS: All 15 patients were followed up 8-16 months, with an average of 13.5 months. There was no infection of incision, loss of reduction of fracture block, delayed union or nonunion. The average time of fracture union was 6.5 months (range, 4-8 months). One patient had axillary paralysis at 1 day after operation, and was treated with nutritional nerve therapy, the symptoms disappeared after 2.5 months. Three patients had slight subacromial impingement. After fracture healing, the hook plate was taken out in advance, and the pain and abnormal noise disappeared during shoulder abduction. At last follow-up, Costant-Murley score used to evaluate shoulder joint function was 88-100, with an average of 96.8; 8 cases were excellent, 7 cases were good, and the excellent and good rate was 100%. The internal fixator was removed after 8-16 months after the secondary operation with no re-fracture occurred. CONCLUSION: The self-made dentation hook plate associated with hot-air balloon technique is a safe and reliable method for the treatment of Mutch Ⅰ or Ⅱ type isolated greater tuberosity fracture of humerus.

SNHG16 promotes osteosarcoma progression and enhances cisplatin resistance by sponging miR-16 to upregulate ATG4B expression.

BACKGROUND: Human osteosarcoma is the most common primary cancer of the bone. Multiple mechanisms underlying cell growth, apoptosis, bone development, and drug resistance are important in the development of osteosarcoma therapy, which remains to be fully studied. METHODS: We collected thirty-paired tumor tissues and the adjacent normal ones from osteosarcoma patients. Two osteosarcoma cell lines (SAOS2, U2OS) were used for in vitro experiments. RT-qPCR and Western blot were used for gene expression detection. We applied starBase to predict the potential binding sites. Then, the luciferase reporter assay was used to confirm the potential direct interaction. Besides, we applied CCK-8, EdU assay, and flow cytometric assays to detect cell growth and apoptosis rate. We used wound healing and transwell assays to determine cell migration and invasion abilities. Additionally, we constructed a cisplatin-resistant osteosarcoma cell line to study the potential impact of the regulatory axis on drug resistance. RESULTS: Small nucleolar RNA host gene 16 (SNHG16) and autophagy-related 4B (ATG4B) were significantly upregulated in osteosarcoma tissues than the normal ones, and the higher expression level of SNHG16 predicted a poor prognosis in osteosarcoma patients. By contrast, the expression level of miR-16 was markedly lower in tumor tissues and was negatively correlated with SNHG16 (p < 0.001). SNHG16 was shown to promote cell growth, migration, and invasion, while miR-16 reversed this impact. Meanwhile, overexpression of ATG4B significantly promoted the development of osteosarcoma cells attenuated by SNHG16 knockdown or miR-16 mimics. Specifically, overexpression of ATG4B promoted cisplatin-induced autophagy and inhibited cell apoptosis rate, which enhanced the cisplatin resistance in osteosarcoma cell lines. CONCLUSIONS: Overall, our findings showed the importance of the regulatory axis of SNHG16/miR-16/ATG4B underlying osteosarcoma progression and chemoresistance to cisplatin. This research would benefit the therapy development in the treatment of osteosarcoma.

[effectiveness of open reduction and internal fixation without opening joint capsule on tibial plateau fracture].

OBJECTIVE: To introduce the surgery method to reset and fix tibial plateau fracture without opening joint capsule, and evaluate the safety and effectiveness of this method. METHODS: Between July 2011 and July 2013, 51 patients with tibial plateau fracture accorded with the inclusion criteria were included. All of 51 patients, 17 cases underwent open reduction and internal fixation without opening joint capsule in trial group, and 34 cases underwent traditional surgery method in control group. There was no significant difference in gender, age, cause of injury, time from injury to admission, side of injury, and types of fracture between 2 groups (P > 0.05). The operation time, intraoperative blood loss, incision length, incision healing, and fracture healing were compared between 2 groups. The tibial-femoral angle and collapse of joint surface were measured on X-ray film. At last follow-up, joint function was evaluated with Hospital for Special Surgery (HSS) knee function scale. RESULTS: The intraoperative blood loss in trial group was significantly less than that in control group (P < 0.05). The incision length in trial group was significantly shorter than that in control group (P < 0.05). Difference was not significant in operation time and the rate of incision healing between 2 groups (P > 0.05). The patients were followed up 12-30 months (mean, 20.4 months) in trial group and 12-31 months (mean, 18.2 months) in control group. X-ray films indicated that all cases in 2 groups obtained fracture healing; there was no significant difference in the fracture healing time between 2 groups (t=1.382, P=0.173). On X-ray films, difference was not significant in tibial-femoral angle and collapse of joint surface between 2 groups (P > 0.05). HSS score of the knee in trial group was significantly higher than that of control group (t=3.161, P=0.003). CONCLUSION: It can reduce the intraoperative blood loss and shorten the incision length to use open reduction and internal fixation without opening joint capsule for tibial plateau fracture. Traction of joint capsule is helpful in the reduction and good recovery of joint surface collapse. In addition, the surgery without opening joint capsule can avoid joint stiffness and obtain better joint function.