I s pelvic support osteotomy (PSO) suitable for ordinary high-riding hip dysplasia?

PURPOSE: Pelvic support osteotomy (PSO) is regarded to provide pelvic stability and improve abductor function to delay or even avoid total hip arthroplasty (THA) in young patients with high-riding hip dysplasia. However, some of these patients eventually have to undergo THA. Because of the double-angulation deformity of the femur after PSO, subsequent THA is challenging. This study aimed to analyze whether PSO surgery is suitable for high-riding hip dysplasia and summarize orthopaedic strategy during THA for patients with previous PSO. METHODS: This case-control study included eight cases of THA for high-riding hip dysplasia patients with previous PSO (study group) and 24 cases of high-riding hip dysplasia patients without any hip surgical therapy (control group) by a 1:3 match (from May 2018 to January 2022). We compared demographics and joint function before and after THA between two groups and recorded all patients' preoperative imaging data, surgical procedures, postoperative imaging data, and complications. The surgical techniques for patients with previous PSO were highlighted. RESULTS: There was no statistical difference between the two groups in demographic (p > 0.05). The study group had worse hip Harris score (HHS), range of motion (ROM), visual analogue scale (VAS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) (p < 0.05) compared with the control group before THA. All patients had concurrent THA and osteotomy at the proximal femur, but the study group experienced longer operation time (p = 0.047) with more blood loss (p = 0.027) and higher complication rate compared with the control group (p = 0.009). At the last follow-up, the study group's HHS, ROM, VAS, and WOMAC were still worse than those in the control group. CONCLUSIONS: PSO did not improve the joint function of high-riding hip dysplasia patients but brought challenges to subsequent THA and affected the surgical outcomes. In short, we suggested that PSO is unsuitable for routine high-riding hip dysplasia patients.

Effect of Long Non-coding RNA and DNA Methylation on Gene Expression in Dental Fluorosis.

In the process of tooth development, the interaction between genetic information, epigenetic inheritance, and environment jointly affects the teeth formation. At present, the mechanism of dental fluorosis is rarely studied from transcriptomics, and there is no report on epigenetic perspective. In the study, SD rats were randomly divided into dental fluorosis group and control group fed with NaF (150 mg/L) or distilled water for 8 weeks. After 3.5 days of birth, the RNAs or DNA of rat mandibular molars were detected by RNA-seq or MethylTarget, respectively. The results demonstrated that a total of 1723 differentially expressed genes (DEGs) and 2511 differential expression lncRNAs (DE-lncRNAs) were mainly involved in the ion channels, calcium ion transport, and immunomodulatory signaling pathways. ATP2C1 and Nr1d1, which were related to Ca2+ transport, cellular calcium homeostasis, endoplasmic reticulum stress and immunity, may be the key genes in the formation of dental fluorosis. Notably, we also found that the immune response plays an important role in the formation of dental fluorosis, and a large amount of DEGs was enriched in immune regulation and NF-κB signaling pathways. Furthermore, the methylation levels of 13 sites were increased in Ago4, Atf3, Atp2c1, Dusp1, Habp4, and Mycl, while methylation levels of 5 CpG sites decreased in Ago4, Atp2c1, Habp4, and Traf6, and conformably, the expression of these genes have been significantly changed. This study comprehensively analyzed the occurrence mechanism of dental fluorosis from transcriptomics and epigenetics, so as to provide theoretical reference for further research.

The invasiveness of robot-assisted total hip replacement is similar to that of conventional surgery.

Robot-assisted total hip arthroplasty (R-THA) is increasingly being performed throughout the world. The invasiveness of this operation is unknown. We retrospectively reviewed the cohort of consecutive osteonecrosis of the femoral head (ONFH) patients who received primary R-THA or manual THA (M-THA) from January 2020 to January 2022 in our institution. One experienced surgeon performed all procedures. We calculated the propensity score to match similar patients in different groups by multivariate logistic regression analysis for each patient. We included confounders consisting of age, sex, body mass index (BMI), and operation time. Preoperative serum markers and Harris hip scores (HHS), postoperative serum markers at first day and third day, complications rate, postoperative HHS and Forgotten Joint Score (FJS) at 6 months after surgery of different cohorts were compared. We analyzed 218 ONFH patients treated with THA (98 R-THA patients, and 120 M-THA patients). After propensity score matching, we generated cohorts of 95 patients in R-THA and M-THA groups. We found no significant difference in preoperative serum markers and HHS. In the R-THA cohort, the PLT count was significantly lower on the postoperative day 1 (192.36 ± 41.72 × 109/L Vs 210.47 ± 72.85 × 109/L, p < 0.05). The Hb level was significantly lower on the postoperative third day in the R-THA cohort (98.52 ± 12.99 g/L Vs 104.74 ± 13.15 g/L, p < 0.05). There was no significant difference in the other serum markers between the cohorts on postoperative day 1 and 3 (p > 0.05). The FJS was significantly higher in the R-THA than M-THA group (p = 0.01). There was no significant difference in the postoperative HHS or complication rate between the groups (p > 0.05). The R-THA is not associated with a serious invasiveness compared to M-THA. Patients who underwent R-THA had a better early function compared to those who underwent M-THA.

Transcriptomic Network Regulation of Rat Tooth Germ from Bell Differentiation Stage to Secretory Stage: MAPK Signaling Pathway Is Crucial to Extracellular Matrix Remodeling.

Hard tissues make up the vast majority of teeth and are mineralized from the surrounding matrix. If the development of tooth germ is affected during mineralization, hypoplasia of the tooth tissue can occur. To better understand the mechanisms mediating hypoplasia, we need to first study normal development. Using a rodent model, we highlight the transcriptomic changes that occur from the differentiation to secretion stages of mandibular molar germs. The tooth germ was dissected from rats at postnatal day 1.5 or 3.5 for high-throughput sequencing. Combining transcriptome analysis and DNA methylation, we identified 590 differentially expressed genes (436 upregulated and 154 downregulated) and 551 differentially expressed lncRNAs (long noncoding RNA; 369 upregulated and 182 downregulated) which were linked to the biological processes of odontogenesis, amelogenesis, tooth mineralization, and the alteration of extracellular matrix (ECM), especially matrix metalloproteinases (MMPs) and elastin. We found DNA methylation changes in 32 selected fragments involved in 5 chromosomes, 26 targets, and 2 haplotypes. Finally, three novel genes were identified: MMP20, Tgfb3, and Dusp1. Further analysis revealed that MMP20 has a role in odontogenesis and amelogenesis by influencing Slc24a4 and DSPP; Tgfb3 is involved in epithelial cell proliferation, cellular component disassembly process, ECM cellular component, and decomposition of cell components. But lncRNA expression could affect DNA methylation and mRNA expression. Moreover, the degree of DNA methylation could also affect the transcriptome level. Thus, Tgfb3 had no difference in DNA methylation, and Dusp1 conferred no difference at the transcriptome level. These three genes were all enriched in the MAPK pathway and played an important role in ECM remodeling. These data suggest that during the period of the bell differentiation stage to the secretory stage, along with enamel/dentin matrix secretion and hard tissue occurrence, the ECM is remodeled via MAPK signaling.

Fixation by Autogenous Cortical Plate Technique on Sites of Subtrochanteric Shortening Osteotomy Contributes to Early Bone Union in Total Hip Arthroplasty for Crowe Type IV Developmental Dysplasia of the Hip.

Aim: Subtrochanteric shortening osteotomy (SSO) is often applied during total hip arthroplasty (THA) in high hip dislocations. The aim of the present paper was to evaluate the results of fixation by autogenous cortical plate technique on sites of SSO in THA for patients with Crowe type IV developmental dysplasia of the hip (DDH). Methods: We conducted a historical prospective cohort study and reviewed 67 patients (82 THAs) with SSO performed between March 2016 and May 2020. Thirty-nine patients (48 hips) obtained stability by intramedullary pressure provided by the S-ROM modular prostheses and with or without prophylactic binding by stainless-steel wire after osteotomy and before stem implantation (group A). Twenty-eight patients (34 hips) were fixed with autogenous cortical plate technique and stainless-steel wire or cables (group B). Time of operations, complications, radiographic results and clinical scores were compared. Results: One intraoperative fracture and a dislocation occurred, while component loosening, ectopic ossification and osteolysis were not observed. Group B had a higher union rate at the 4th month than group A (P = 0.015) while there were no significant differences of union rates at the 8th (P = 0.811) and the 12th month (P = 0.722) and of the average healing time (P = 0.181). No significant differences were found in hip function scores (HHS and WOMAC Osteoarthritis Index) between two groups. Conclusion: Fixation with autogenous cortical plate from the cylinder of femoral bone contributes to early bone union of osteotomy ends in Crowe type IV DDH patients compared to those who do not apply the technique. Besides of application of autogenous cortical strut grafts, relevant measures are as well recommended to prevent nonunion after SSO.

Effects of Surgeon Handedness on the Outcomes of Unicompartmental Knee Arthroplasty: A Single Center's Experience.

OBJECTIVE: Surgeon handedness has been widely discussed in operative surgery, and could cause clinical discrepancy. However, few studies have reported the effect of handedness on unicompartmental knee arthroplasty (UKA). Based on our clinical observation and case analysis, we aimed to find out the effects of surgeon handedness on UKA. METHODS: We retrospectively studied 94 UKA procedures performed by one right-handed surgeon from January 2017 to December 2018 at a single medical center. The cases were divided into two groups by operation side (49 L-UKAs and 45 R-UKAs). Preoperative demographic data were collected. Imaging parameters (femorotibial and hip-knee-ankle angles and tibial-plateau retroversion) and joint function scores (Knee Society Score [KSS] and Oxford Knee Score [OKS]) were recorded. Patients were followed up regularly and Forgotten Joint Score (FJS) was calculated at the last follow-up. All data were compared between the two groups with independent-samples t-test, and paired t-test was used for intragroup comparisons. RESULTS: The average follow-up was 26.7 ± 3.2 months. The average patient age was 63.5 ± 9.0 years and the average body mass index was 26.89 ± 3.43 kg/m2 . There was no significant group difference in any preoperative characteristic. Both the KSS and OKS improved significantly after surgery (p < 0.05). No significant group difference was found between the KSS or OKS at any follow-up visit. The varus or valgus of tibial component was 3.57 ± 1.42° on the left side and 3.19 ± 1.56° on the right side (p = 0.45). The varus or valgus of femoral component was 7.81 ± 2.43° in patients undergoing L-UKA and 7.05 ± 2.90° in those undergoing R-UKA (p = 0.04). No statistical differences were found in outliers of component orientation on both sides. The femorotibial and hip-knee-ankle angles improved significantly in both groups, and there was no significant group difference in either lower limb alignment or tibial-plateau retroversion. The complication rate was 8.16% (4/49) in the L-UKA group and 6.67% (3/45) in the R-UKA group. There was no correlation between prosthesis orientation and early joint function score. CONCLUSIONS: Surgeon handedness may cause a worse prosthetic orientation on femoral side during surgeon's non-dominant UKA, and surgeons should be cautious of bone resection and prosthesis implantation. However, radiographic difference did not bring variations on short-term clinical outcomes or lower limb alignment.

Robotic-assisted versus manual total hip arthroplasty in obese patients: a retrospective case-control study.

AIMS: The objective of this study was to evaluate the accuracy of acetabular cup positioning in the obese patients when using robotic-assisted technology during total hip arthroplasty (THA). METHODS: Data were retrospectively collected from patients who underwent primary (THA) with a body mass index (BMI) ≥ 28 kg/m2 and ≥ 1 year of follow-up between January 2018 and December 2019. Their demographics, diagnosis, acetabular cup positioning, American Society of Anesthesiologists (ASA) score, Harris Hip Score (HHS), and Forgotten Joint Score (FJS) at the final follow-up were recorded for analysis. RESULTS: There were no statistically significant differences between the two groups in height, weight, BMI, ASA score, or preoperative Harris Hip Score (HHS). Also, there was no difference in inclination angle between the two groups (R-THA: 41.29° ± 3.04°; manual THA (M-THA): 40.47° ± 5.46°; P = 0.312). However, the mean anteversion angle was greater in the R-THA group (20.71° ± 1.98° vs. 19.08° ± 4.04°; P < 0.001). Compared to M-THA, R-THA more frequently achieved an acetabular cup angle within 5° of the target (anteversion, 98.1% vs. 78.1% P = 0.001; inclination, 88.5% vs. 53.1%, P < 0.001). The R-THA group was more advantageous in restoring the hip center of rotation (COR) and leg length difference (LLD). There was no statistical difference in postoperative HHS (P = 0.404) or FJS (P = 0.497) between the two groups. CONCLUSIONS: Compared to manual technique, robotic-assisted technique provided more precise acetabular cup positioning and better leg length restoration for obese patients. The robotic-assisted technique was more advantageous in recovering the center of rotation position and achieved a higher proportion of the acetabular cup placed in the target safety zone. Further studies are needed to confirm the clinical outcomes of surgeries in obese patients using robotic-assisted technology.

Erratum to "Nonsurgical Management of Distal Femur Stem Cortical Perforation" [Arthroplasty Today 6 (2020) 153-157].

[This corrects the article DOI: 10.1016/j.artd.2020.03.002.].

The Course and Anatomical Characteristics of Sciatic and Femoral Nerves in Unilateral Crowe Type-IV Hip Dysplasia.

Background: This study aims to investigate the course and anatomical characteristics of sciatic and femoral nerves in unilateral Crowe type-IV developmental dysplasia of the hip (DDH) patients. Methods: We conducted a retrospective own-control study of patients with unilateral Crowe type-IV DDH. Bilateral hip computed tomography (CT) of 21 female patients was reviewed in our institute from February 2018 to February 2020. The distances between nerves and bony landmarks were measured in different CT sections (anterior superior iliac spine, acetabular inner wall, teardrop, and ischial tuberosity) to analyze the anatomical position and course of sciatic and femoral nerves between bilateral hips. Results: In the section of the acetabular inner wall, the distance between the femoral nerve and the acetabular anterior wall in affected hip (13.20 ± 3.59 mm) was significantly smaller than that in the healthy hip (16.58 ± 5.12mm) (p < 0.001). In other sections, the distances between nerves and bony landmarks in affected hips were significantly larger than or equal to those in the healthy hips. Conclusion: In female patients with unilateral Crowe type-IV DDH, the femoral nerve in the affected hip runs closer to the anterior acetabular wall than that in the healthy hip.

[A comparative study of three different fixation methods after subtrochanteric shortening osteotomy in total hip arthroplasty for Crowe type â £ developmental dysplasia of the hip].

OBJECTIVE: To compare the effectiveness of three different fixation methods after subtrochanteric shortening osteotomy (SSO) in total hip arthroplasty (THA) for Crowe type Ⅳ developmental dysplasia of the hip (DDH). METHODS: A clinical data of 63 patients (78 hips) with Crowe type Ⅳ DDH, who underwent THA with SSO between November 2014 and May 2019, was retrospectively analyzed. Among them, 18 patients (20 hips) obtained stability by intramedullary pressure provided by the S-ROM modular prostheses (group A); 22 patients (30 hips) underwent prophylactic binding by stainless steel wire after osteotomy and before stem implantation (group B); 23 patients (28 hips) were fixed with autogenous cortical strut grafts and stainless steel wire or cables (group C). There was no significant difference in gender, age, body mass index, affected limb side, and preoperative Harris score between groups ( P>0.05). The operation time, complications, imaging results, hip functional score of the three groups were recorded and compared. RESULTS: There was no significant difference in the operation time between groups ( P>0.05). All incisions healed by first intention. All patients were followed up, and the follow-up time was 2.5-4.0 years (mean, 3.1 years) in group A, 1.5-5.5 years (mean, 3.2 years) in group B, and 1.0-5.0 years (mean, 1.6 years) in group C. There was no significant difference in Harris score or Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score between groups at 4 and 12 months after operation ( P>0.05). X-ray films showed that there was no significant difference in osteotomy healing rate at 4, 8, and 12 months after operation and the osteotomy healing time between groups ( P>0.05). There was no complications such as joint dislocation, prosthesis loosening, prosthetic joint infection, or heterotopic ossification during follow-up, except for the distal femoral fracture of 1 hip during operation in group B. CONCLUSION: In THA for patients with Crowe type Ⅳ DDH, the stainless steel wire binding alone and autogenous cortical strut grafts combined with stainless steel wire or cable binding can not significantly promote the osteotomy healing compared with femoral prosthesis intramedullary compression fixation. For patients with nonmatched medullary cavity after SSO, it is recommended to apply autogenous cortical strut grafts with wire or cables for additional fixation.

[A study of low back pain and changes in spinal sagittal parameters after total hip arthroplasty in patients with unilateral Crowe type â £ developmental dysplasia of the hip].

OBJECTIVE: To investigate the changes of low back pain (LBP) and spinal sagittal parameters in patients with unilateral Crowe type Ⅳ developmental dysplasia of the hip (DDH) after total hip arthroplasty (THA). METHODS: The clinical data of 30 patients who met the selection criteria between October 2018 and March 2020 were retrospectively analyzed. Patients were divided into LBP group (16 cases) and control group (14 cases) according to whether there was LBP before operation. There was no significant difference between the two groups of patients in gender, age, body mass index, affected sides, preoperative Harris score ( P>0.05). Full-length lateral X-ray films of the spine were taken within 1 week before operation and at 1 year after operation, and the following imaging indicators were measured: sacral slope (SS), lumbar lordosis (LL ), spinal tilt (ST), spine-sacral angle (SSA), sagittal vertebral axis (SVA). The visual analogue scale (VAS) score, lumbar Oswestry disability index (ODI), the Harris score of the hip joint before operation and at 1 year after operation, and the occurrence of postoperative complications were collected and analysed. RESULTS: In the LBP group, LBP was relieved to varying degrees at 1 year after operation, of which 13 patients (81.3%) had complete LBP remission; VAS score decreased from 4.9±2.3 preoperatively to 0.3±0.8, ODI decreased from 33.5±22.6 preoperatively to 1.3±2.9, the differences were all significant ( t=7.372, P=0.000; t=5.499, P=0.000). There was no new chronic LBP in the control group during follow-up. The Harris scores of the two groups significantly improved when compared with those before operation ( P<0.05); there was no significant difference between the two groups at 1 year after operation ( t=0.421, P=0.677). There was no significant difference in imaging indexes between the two groups before operation and the difference between pre- and post-operation ( P>0.05). At 1 year after operation, ST and SVA in the LBP group, SSA in the control group, and SS in the two groups significantly improved when compared with those before operation ( P<0.05); there was no significant difference in the other indexes between the two groups before and after operation ( P>0.05). CONCLUSION: Unilateral Crowe type Ⅳ DDH patients with LBP before operation were all relieved of LBP after THA. The relief of LBP may be related to the improvement of spinal balance, but not to lumbar lordosis and its changes.

[Measurement and analysis of leg length in adults with unilateral developmental dysplasia of the hip].

OBJECTIVE: To measure and analyze the radiographic characteristics of the leg length discrepancy in adult patients with unilateral developmental dysplasia of the hip (DDH). METHODS: The clinical data of 112 patients with unilateral DDH who met the selection criteria between January 2016 and June 2018 were retrospectively analyzed. There were 16 males and 96 females with an age of 20-76 years (mean, 42.9 years). According to the Crowe classification, there were 25 hips of type Ⅰ, 26 hips of type Ⅱ, 15 hips of type Ⅲ, and 46 hips of type Ⅳ (26 hips of type ⅣA without secondary acetabular formation, and 20 hips of type ⅣB with secondary acetabular formation). Full-length X-ray films of the lower limbs in the standing position were used to measure the following parameters: greater trochanter leg length (GTLL), greater trochanter femoral length (GTFL), lesser trochanter leg length (LTLL), lesser trochanter femoral length (LTFL), tibial length (TL), and intertrochanteric distance (ITD). The above parameters on the healthy and affected sides were compared and the difference of each parameter between the healthy and affected sides was calculated. Taking the difference of 5 mm between the healthy side and the affected side as the threshold value, the number of cases with the healthy side was greater than 5 mm and the affected side was greater than 5 mm were counted respectively. The difference of the imaging parameters between the healthy side and the affected side were compared between different Crowe types and between type ⅣA and type ⅣB. RESULTS: There was no significant difference in GTLL and LTFL between healthy and affected sides ( P>0.05); LTLL and TL of affected side were longer than healthy side, GTFL and ITD were shorter than healthy side, and the differences were significant ( P<0.05). The constituent ratio of long cases on the affected side of TL and LTLL was greater than the constituent ratio of long cases on the healthy side, while the constituent ratio of long cases on the healthy side of GTFL and ITD was greater than the constituent ratio of long cases on the affected side; there was no obvious difference in the constituent ratio of long cases on the healthy side or the affected side of GTLL and LTFL. The comparison between different Crowe types showed that only the difference in TL between type Ⅰ and type Ⅳ was significant ( P<0.05), the difference of each imaging parameter among the other types showing no significant difference ( P>0.05). Compared with type ⅣB, the differences of GTLL, TL, and ITD of type ⅣA were bigger, and the differences were significant ( P<0.05); the differences of other parameters between type ⅣA and type ⅣB were not significant ( P>0.05). CONCLUSION: In adult unilateral DDH patients, the leg length on the healthy side and the affected side is different, and the difference mainly comes from the TL and ITD, which should be paid attention to in preoperative planning.

A Prospective, Randomized and Controlled Study on Tissue Adhesive for Skin Incision in Total Knee Arthroplasty.

BACKGROUND: The study focusing on the tissue adhesive in total knee arthroplasty (TKA) was rare. This study aimed to evaluate the clinical outcomes and economic costs of tissue adhesive when acting as the adjunct to standard incision closure in TKA. PATIENTS AND METHODS: From September 2019 to November 2019, we prospectively enrolled the consecutive patients who underwent simultaneous bilateral TKA in our institute. The allocation using the tissue adhesive was done after the subcuticular suture in right knee first and another method was applied in the left knee automatically. The patients' demographics, length of stay (LOS), times of dressing changes and incision-related cost, range of motion (ROM), incision-related complications and incision evaluation scores were recorded. RESULTS: Thirty-two patients were enrolled in this study and followed at two months after surgery. In the knees of tissue adhesive, the times of dressing change and patient scar assessment scores (PSAS) were significantly less than those standard skin closure (p=0.000; p=0.003). Although there were no significant differences of the delayed discharge, incision-related cost, ROM, incision-related complications and Vancouver scar score (VSS) between two groups, 65.6% (21/32) patients preferred the tissue adhesive and only 15.6% (5/32) patients preferred the standard incision closure. CONCLUSION: Tissue adhesive could effectively reduce postoperative wound drainage and improve patients' satisfaction rate with no difference in medical costs and ROM in TKA. The application of tissue adhesive and subcuticular sutures might be one safe and convenient method of skin closure in TKA. CHINESE CLINICAL TRIAL REGISTRY: ChiCTR1900025730; Registered 6 September 2019.

A Surgeon's handedness in direct anterior approach-hip replacement.

BACKGROUND: The impact of handedness on clinical outcomes was easily overlooked in hip replacement. This study aimed to find whether the component positioning and hip function were affected by the handedness in total hip arthroplasty (THA) through direct anterior approach (DAA). METHODS: Total 102 patients who underwent bilateral DAA-THAs simultaneously between May 2016 and November 2018 in our institute were reviewed. All surgeries were operated by one right-handed surgeon. Their demographic, cup positioning, stem alignment, femoral stem fit, Harris hip score (HHS), intraoperative and postoperative complications were used to evaluate the role of handedness in DAA. RESULTS: The inclination of left cups was significantly larger than that of right cups (42.61 ± 7.32 vs 39.42 ± 7.19, p = 0.000). The stem fit of left femur was significantly larger than that of right femur (84.34 ± 4.83 vs 82.81 ± 6.07, p = 0.043). No significant differences in safe zone ratio, HHS and complications between bilateral hips were found. CONCLUSIONS: A surgeon's handedness had significant impact on cup's inclination and femoral stem fit in DAA-THA. However, there were no significant differences of cup malpositioning, stem alignment, hip function scores and complications between bilateral DAA-THAs.

Research on intelligent prediction and zonation of basin-scale flood risk based on LSTM method.

Global climate change and human activities aggravate the frequency of flood disasters. Flood risk includes natural flood risk and risk of economic and social disasters, which is displayed intuitively by flood risk zonation maps. In this paper, we take the disaster-causing factors, the disaster environment, the disaster-bearing body, and the disaster prevention and mitigation capability into consideration comprehensively. Eleven influencing indexes including annual maximum 3-day rainfall and rainfall in flood season are selected, and the virtual sown area of crops is innovated. Taking the Huaihe River Basin (HRB) as the research area, the flood risk prediction of the basin is explored by using the long short-term memory (LSTM). The results show that LSTM can be successfully applied to flood risk prediction. The short-term prediction results of the model are good, and the area where the risk is seriously underestimated (the high and very high risk are identified as the very low risk) accounts for only 0.98% of the total basin on average. The prediction results can be used as a reference for watershed management organizations, so as to guide future flood disaster prevention.

Robot-Assisted Total Hip Arthroplasty for Arthrodesed Hips.

BACKGROUND: Conversion of arthrodesed hips to total hip arthroplasty (THA) remains technically demanding. This study aims to evaluate the safety and efficacy of robot-assisted THA in arthrodesed hips. METHODS: We retrospectively analyzed 45 ankylosing spondylitis patients with hip arthrodesis in the Chinese PLA General Hospital between August 2018 and August 2019. All surgeries were carried out by one single surgeon. The patients were followed at 3 months after surgery. Gender, body mass index, angle of hip arthrodesis, operating time, intraoperative fluoroscopic times, postoperative length of hospitalization, cup positioning, postoperative leg length discrepancy, offset discrepancy, intraoperative and postoperative complications, and postoperative Harris Hip Score were collected for all patients. RESULTS: Twenty-two patients (35 hips) who underwent robot-assisted THA and 23 patients (37 hips) who underwent manual THA were enrolled in this study. There were no significant differences in demographics and arthrodesed angles between the two groups. The fluoroscopic times during manual THA were significantly higher than those during robot-assisted THA (2.16±1.61 vs 0.47±0.61, respectively, p=0.000). In the robotic group, the percentage of acetabular cups within the safe zone was significantly greater than in the manual group (94.29% vs 67.56%, respectively, p=0.042). For manual THA, the anteversions were significantly different between the left and right sides (21.14±7.86 vs 16.00±6.32, respectively, p=0.042); however, no such significant difference was found in robot-assisted THA. CONCLUSION: Compared with manual THA for arthrodesed hips, robot-assisted THA had significant advantages in improving the frequency of achieving cup positioning within the target zone with diminished radiation dose and no increase in operating time.

Nonsurgical Management of Distal Femur Stem Cortical Perforation.

Distal femur stem cortical perforation is a rare but potentially catastrophic complication during total hip arthroplasty. If unrecognized, it can lead to transverse fracture of the femur while the patient is ambulating. If an uncemented femur stem was used, previous literature unanimously agrees that revision surgery should be performed. We report a case of uncemented distal femur stem cortical perforation that was treated nonsurgically successfully with protected weight-bearing for 6 weeks. Our patient had previous osteotomy surgeries of the proximal femur with a residual deformity which increased her risk for distal femur stem cortical perforation. At 40-month follow-up, she was asymptomatic, ambulated with normal gait, and was able to perform deep squats. The discussion involves avoiding, recognizing, and managing distal femur stem cortical perforation.

Impact of surgeon handedness in manual and robot-assisted total hip arthroplasty.

BACKGROUND: The purpose of this study was to examine whether surgeon handedness could affect cup positioning in manual total hip arthroplasty (THA), and whether robot could diminish or eliminate the impact of surgeon handedness on cup positioning in robot-assisted THA. METHODS: Fifty-three patients who underwent bilateral robot-assisted THA and sixty-two patients who underwent bilateral manual THA between August 2018 and July 2019 in our institute were respectively analyzed in this study. When the difference between the bilateral anteversion and inclination was greater than 5°, the patient was regarded as having different cup positioning between bilateral THA. Their demographics, orientation of acetabular cup, and postoperative 3 month Harris hip score (HHS) were recorded for analysis. RESULTS: There were no significant differences in the gender, age, BMI, diagnosis's composition, and preoperative and postoperative HHS between the robotic and manual group. Two left hips dislocated in the manual group. The anteversion of left hip was significantly larger than that of right hip (24.77 ± 10.44 vs 22.44 ± 8.67, p = 0.043) in the manual group. There were no significant differences of cup positioning between bilateral robot-assisted THA. The patients in manual group were significantly more likely to have different cup positioning between bilateral hips than those in robotic group (77% vs 45%, p = 0.000). More manual THA were located out of the target zone than robot-assisted THA (70% vs 48%, p = 0.001). CONCLUSIONS: Surgeon's handedness showed a trend towards an impact on cup positioning in manual THA and robot might help surgeon eliminate the adverse impact. However, the impact of handedness on the clinical outcomes still needs further observation.

A retrospective study comparing a single surgeon's experience on manual versus robot-assisted total hip arthroplasty after the learning curve of the latter procedure - A cohort study.

BACKGROUND: Robot-assisted total hip arthroplasty (THA) has the potential of improving cup positioning. However, there is an associated learning curve with robot. This study aimed to determine one surgeon's learning curve with robot-assisted THA and whether robot could achieve similar accuracy in cup positioning as manual THA. METHODS: The first 100 robot-assisted THA operated by one experienced surgeon on manual THA was respectively reviewed. The operating time and robotic complications were recorded to calculate the learning curve through cumulative summation analysis. The demographics, operating time, cup positioning, leg length discrepancy, hip offset, robotic complications and hip Harris score between proficient robot-assisted THA and manual THA in the same period were also compared. RESULTS: The average operating time of robot-assisted THA was 95.92 ± 15.64 min, ranging from 68 to 145 min. Robot-assisted THA was associated with a learning curve of 14 cases for operating time. The duration of acetabular registration and cup implantation between two phases (1-14 and 15-100 case) had significant differences. There were 92% proficient robot-assisted THA and 82% manual THA respectively locating within the Lewinnek's safe zone. The variation of inclinations in proficient robot-assisted THA was significantly less than that in manual THA. CONCLUSION: In the surgeon's series, it took 14 cases' learning curve to be proficient in robot-assisted THA. In the proficiency phase, robot had an advantage in cup positioning than manual technique.

Tissue adhesive for wound closure in enhanced-recovery total hip arthroplasty: a prospective, randomized and controlled study.

BACKGROUND: We aimed to present our experience of adopting tissue adhesive as adjunct to standard wound closure in total hip arthroplasty (THA) and evaluate its performance. METHODS: From September 2019 to November 2019, we prospectively enrolled consecutive patients who underwent simultaneous bilateral THA in this randomized and controlled study. Standard wound closure was applied on one side of hip while additional tissue adhesive was applied on the other side at random. We collected and analyzed patients' information, including age, gender, body mass index (BMI), diagnosis, postoperative length of stay (LOS), dressing changes, wound evaluation scores, wound-related cost and complications. RESULTS: Thirty patients with simultaneous bilateral THA were enrolled in this study. During the hospital stay, the times of dressing change in hips with tissue adhesive was significantly less than that in the other hips (p = 0.000). However, the wound-related cost in hips with tissue adhesive was significantly higher (p = 0.000). According to patients' feedback at one-month follow-up, wound evaluation of hips with tissue adhesive was significantly better than the other hips (p = 0.004). Seventeen patients preferred tissue adhesive and only five patients preferred standard wound closure. CONCLUSIONS: Tissue adhesive could significantly reduce wound drainage and increase patients' satisfaction, which can be an ideal adjunct to standard wound closure in enhanced-recovery THA. TRIAL REGISTRATION: Chinese Clinical Trial Registry; ChiCTR1900025730; Registered 6 September 2019.