A Deep Learning Model Enhances Clinicians' Diagnostic Accuracy to More Than 96% for Anterior Cruciate Ligament Ruptures on Magnetic Resonance Imaging.

PURPOSE: To develop a deep learning model to accurately detect anterior cruciate ligament (ACL) ruptures on magnetic resonance imaging (MRI) and to evaluate its effect on the diagnostic accuracy and efficiency of clinicians. METHODS: A training dataset was built from MRIs acquired from January 2017 to June 2021, including patients with knee symptoms, irrespective of ACL ruptures. An external validation dataset was built from MRIs acquired from January 2021 to June 2022, including patients who underwent knee arthroscopy or arthroplasty. Patients with fractures or prior knee surgeries were excluded in both datasets. Subsequently, a deep learning model was developed and validated using these datasets. Clinicians of varying expertise levels in sports medicine and radiology were recruited, and their capacities in diagnosing ACL injuries in terms of accuracy and diagnosing time were evaluated both with and without artificial intelligence (AI) assistance. RESULTS: A deep learning model was developed based on the training dataset of 22,767 MRIs from 5 centers and verified with external validation dataset of 4,086 MRIs from 6 centers. The model achieved an area under the receiver operating characteristic curve of 0.987 and a sensitivity and specificity of 95.1%. Thirty-eight clinicians from 25 centers were recruited to diagnose 3,800 MRIs. The AI assistance significantly improved the accuracy of all clinicians, exceeding 96%. Additionally, a notable reduction in diagnostic time was observed. The most significant improvements in accuracy and time efficiency were observed in the trainee groups, suggesting that AI support is particularly beneficial for clinicians with moderately limited diagnostic expertise. CONCLUSIONS: This deep learning model demonstrated expert-level diagnostic performance for ACL ruptures, serving as a valuable tool to assist clinicians of various specialties and experience levels in making accurate and efficient diagnoses. LEVEL OF EVIDENCE: Level III, retrospective comparative case series.

Synthesis of sulfinamides via photocatalytic alkylation or arylation of sulfinylamine.

Sulfinamides are a versatile class of compounds that find applications in both organic synthesis and pharmaceuticals. Here we developed an efficient photocatalytic approach for the convenient preparation of sulfinamides. Commercially available potassium trifluoro(organo)borates and readily available sulfinyl amines are rationally used and converted to a series of alkyl or aryl sulfinamides in moderate to high yields. The reaction allows for the gram-scale preparation of sulfinamides. Moreover, sulfonimidamides, sulfonimidate esters and sulfonyl amides could be obtained in one pot.

Preparation of Dihydronaphthofurans from α-Hydroxyl Ketones via a One-Pot Multicomponent Reaction Based on Heyns Rearrangement.

Polysubstituted 1,2-dihydronaphthofurans were efficiently obtained in high yields and good diastereoselectivities with readily available substrates. The reaction proceeds smoothly via a series of tandem reactions, including Heyns rearrangement, oxidation, Friedel-Crafts reaction, and cyclization. The high stereoselectivity of the reaction is ascribed to the activation of the imine via an intramolecular hydrogen bond. Air is directly used as the oxidation medium, which makes the reaction safe and easy to perform. Moreover, the reaction features multiple components, which ensures the diversity of products.

Catalytic asymmetric synthesis of N-substituted tetrahydroquinoxalines via regioselective Heyns rearrangement and stereoselective transfer hydrogenation in one pot.

N-Substituted tetrahydroquinoxalines (37 examples) were step-economically obtained in good yield (<97%) and ee (<99%) with readily available substrates. The reaction proceeds through an interesting regioselective Heyns rearrangement/enantioselective transfer hydrogenation in one pot. The substrate scope and the reaction mechanism were systematically investigated.

Regioselective, Diastereoselective, and Enantioselective One-Pot Tandem Reaction Based on an in Situ Formed Reductant: Preparation of 2,3-Disubstituted 1,5-Benzodiazepine.

The 1,5-benzodiazepines are important skeletons frequently contained in medicinal chemistry. Herein, we described an unexpected tandem cyclization/transfer hydrogenation reaction for obtaining chiral 2,3-disubstituted 1,5-benzodiazepines. The enolizable aryl aldehydes were chosen as substrates to react with symmetric and unsymmetric o-phenylenediamines. The unforeseen tandem reaction occurred among many possible latent side reactions under chiral phosphoric acid catalysis and affords the corresponding products in moderate yields and regioselectivities, good diastereoselectivities, and enantiomeric ratio (up to 99:1).

Correction: Chondroitin sulfate-polydopamine modified polyethylene terephthalate with extracellular matrix-mimetic immunoregulatory functions for osseointegration.

Correction for 'Chondroitin sulfate-polydopamine modified polyethylene terephthalate with extracellular matrix-mimetic immunoregulatory functions for osseointegration' by Ya-Min Li et al., J. Mater. Chem. B, 2019, 7, 7756-7770, DOI: 10.1039/C9TB01984G.

Chondroitin sulfate-polydopamine modified polyethylene terephthalate with extracellular matrix-mimetic immunoregulatory functions for osseointegration.

Optimal integration between the polyethylene terephthalate (PET) graft and host bone is a prerequisite to obtain a satisfactory outcome after graft implantation for ligament reconstruction. Recent studies indicate that complex biosignals including immunoregulation, cell recruitment, and osteogenic differentiation provided by the extracellular matrix (ECM) are conducive to promoting osseointegration. In the present study, a chondroitin sulfate (CS)/polydopamine-modified PET graft was developed to regulate the local immune microenvironment, guide stem cell behavior, and promote new bone formation. We found that CS-modified PET grafts significantly regulated the macrophage phenotype switching from M1 to M2 and promoted the expression of pro-repair cytokines including interleukin (IL)-4, IL-10 and transforming growth factor (TGF)-ß1. Moreover, the immunoregulatory function of CS-modified PET guided stem cell behaviors, including recruitment, adhesion, and proliferation, and enhanced the osteogenic differentiation of stem cells. In vivo experiments confirmed that CS-modified PET switched the local immune microenvironment status from pro-inflammatory to anti-inflammatory, up-regulated osteogenic marker expression, and promoted the bone regeneration process, so as to achieve graft-bone osseointegration. These results indicate that an ECM-biomimetic immunoregulatory coating is an effective approach to promote graft integration. This study proposes an effective strategy for an artificial graft to achieve graft-bone osseointegration through immunoregulatory osteogenesis.

Prevalence of bilateral Discoid Lateral Menisci (DLM) in patients operated for symptomatic DLM with a follow-up study on their asymptomatic contralateral knees: a Magnetic Resonance Imaging (MRI) assessment.

BACKGROUND: The purpose was to investigate prevalence of bilateral discoid lateral menisci (DLM) in Han Chinese patients who received surgery for symptomatic DLM, as well as a follow-up study of their asymptomatic contralateral knees using magnetic resonance imaging (MRI). METHODS: A total of 110 patients [50 males and 60 females; average age: 21.95 ± 12.77 years (range: 6 to 67 years)] admitted to our hospital with symptomatic DLM were treated with arthroscopic surgery. The contralateral asymptomatic knees were evaluated for DLM by MRI. Postoperative clinical evaluation was performed using the Lysholm knee scoring scale and International Knee Documentation Committee subjective knee evaluation. RESULTS: Eighty (72.73%) of 110 symptomatic DLM patients had bilateral DLM, of which 68 (85%) were of homotype (same type). Fourteen of 80 bilateral DLM patients were symptomatic and received operations in both knees. Twelve of remaining 66 bilateral DLM patients with asymptomatic one knee underwent a second arthroscopic surgery as their asymptomatic knees became symptomatic over the five-year interim. Of these 12 cases, seven exhibited no shift and five showed posterocentral meniscal shift. Furthermore, at least two cases showed progression from asymptomatic grade II to symptomatic grade III over the interim. All patients showed significant improvement after surgery. CONCLUSIONS: The bilateral DLM rate of Han Chinese patients with symptomatic DLM was relatively high at 72.7 %, and 85 % of those were of homotype.

Arthroscopic reduction and fixation for isolated greater tuberosity fractures.

BACKGROUND: Traditionally, displaced greater tuberosity fractures are treated with open reduction and internal fixation. Arthroscopic treatment and outcome of greater tuberosity fractures is far from comprehensive. The objective of the current study was to assess the surgical procedure and outcome of an arthroscopic method in the treatment of isolated greater tuberosity fractures. METHODS: From January 2006 to December 2009, 23 patients with isolated greater tuberosity fractures were treated with an arthroscopic procedure using three cannulated screws combined with washers. During follow-up, radiographs and the constant shoulder score (CSS) were used to evaluate the outcome. RESULTS: Three cannulated screws with washers were used to fix the fractured fragment of the greater tuberosity under an arthroscope. All incisions healed at primary intention without infection. The mean duration of follow-up was 20 months (range 18 - 36 months). Fracture fixation was excellent, and fractures healed 2 - 6 months (mean 3.8 months) after surgery. At final follow-up, the CSS was 92 (range 86 - 100). CONCLUSIONS: The described arthroscopic procedure provides anatomical reduction and firm fixation for isolated greater tuberosity fractures. It is a successful and minimally invasive procedure with satisfying therapeutic effects as well as excellent functional recovery.

The effect of remnant preservation on patterns of gene expression in a rabbit model of anterior cruciate ligament reconstruction.

BACKGROUND: Anterior cruciate ligament (ACL) reconstruction with remnant preservation technique had been thought to be a more favorable milieu for graft reinnervation, revascularization, and ligamentization. However, the influence of preserving tibial residual fibers on mRNA expression during the graft remodeling process has never been investigated. MATERIALS AND METHODS: Healthy mature New Zealand white rabbits were randomly assigned to one of four groups: remnant dissected, remnant preserved, sham operated, and normal control. Ligament tissue was dissected at 2, 6, and 12 wk after surgery, and real-time PCR was performed using primers for VEGF, TGF-ß1, COLlAl, COL3A1, GAP-43, and NT-3. RESULTS: In the remnant preservation group, mRNA levels for matrix components COL l Al, COL3A1, growth factor TGF-ß1, and nerve-related genesGAP-43 all increased 6 wk after surgery, compared with the remnant dissection group (P < 0.05). An increased level of VEGF mRNA was also detected in the remnant preservation group 12 wk after operation (P < 0.05). An increased level of NT-3 mRNA was also observed in the remnant preservation group 2 and 12 wk after operation (P < 0.05). CONCLUSIONS: Our results suggest that there is a time dependent alteration of angiogenesis-promoting, repair-related, and nerve-related gene expression after ACL reconstruction during the process of graft remodeling. Furthermore, they demonstrate that remnant preservation in ACL reconstruction determines the different molecular profiles of these target genes, especially during the early stages of graft remodeling, which perhaps explains the potential role in promoting revascularization, reinnervation, and ligamentization.

[Arthroscopic treatment of acute greater tuberosity fractures of the humerus].

OBJECTIVE: To study the outcome in the arthroscopic treatment of acute greater tuberosity fractures. METHODS: Twelve cases with acute great tuberosity fractures received reduction with arthroscopic treatment from August 2006 to December 2007. There were 7 males and 5 females. Eight cases were on left side and 4 on right side. The patients were operated at a mean age of 38 years old (range: 2745). The fractured fragments in displacements were greater than 5 mm. X-ray film and Constant score were used to evaluate the post-operative outcome. RESULTS: Three hollowed threaded screws with a washer were used to fix the big fractured fragments. The post-operative follow-up was a mean of 18 months (range: 14-33). The fracture fixations were excellent and bone union occurred. The patients received a mean Constant score of 92 (86-100) at the last follow-up. CONCLUSION: Arthroscopic treatment of acute greater tuberosity fractures is quite efficacious.

Single-bundle posterior cruciate ligament reconstruction with remnant preservation: lateral versus medial-sided augmentation technique.

OBJECTIVE: To compare the results of lateral versus medial-sided augmentation techniques in single-bundle posterior cruciate ligament (PCL) reconstruction with remnant preservation. METHODS: Forty-two cases of isolated chronic PCL ruptures were reconstructed in a single-bundle manner with remnant preservation. The patients were randomly separated into two groups: in the medial-sided augmentation (MSA) group the graft passed through the medial side of the remnant and in the lateral-sided augmentation (LSA) group it passed through the lateral side. RESULTS: Nineteen patients in the MSA group and 17 in the LSA group were followed up for a minimum of 2 years. At the final follow-up, the average side-to-side differences in posterior laxity were 1.6 ± 1.2 mm and 1.5 ± 1.3 mm respectively in the MSA and LSA groups. According to the International Knee Documentation Committee (IKDC) scale, patient numbers graded as normal, nearly normal and abnormal were 14 (73.7%), 4 (21.1%), and 1 (5.3%) in the MSA group, and 13 (76.5%), 3 (17.6%), and 1 (5.9%) in the LSA group. The IKDC subjective scores were 93.1 ± 3.8 and 92.6 ± 4.1, the Lysholm scores were 95.0 ± 4.6 and 93.7 ± 4.2, and the Tegner scores were 5.4 ± 0.9 and 5.6 ± 0.7 respectively in the MSA and LSA groups. Statistical analysis showed no significant differences between the MSA and the LSA group regarding all subjective and objective results. CONCLUSION: In single-bundle PCL reconstruction with remnant preservation, similar subjective and objective results can be obtained with MSA and LSA techniques.

A new treatment strategy for severe arthrofibrosis of the knee. Surgical technique.

BACKGROUND: To reduce the morbidity of traditional quadricepsplasty for the treatment of severe arthrofibrosis of the knee, we instituted a treatment regimen consisting of an initial extra-articular mini-invasive quadricepsplasty and subsequent intra-articular arthroscopic lysis of adhesions during the same anesthesia session. The purpose of the present study was to determine the results of this technique. METHODS: From 1998 to 2001, twenty-two patients with severely arthrofibrotic knees were managed with this operative technique. The mean age of the patients at the time of the operation was thirty-seven years. After a mean duration of follow-up of forty-four months (minimum, twenty-four months), all patients were evaluated according to the criteria of Judet and The Hospital for Special Surgery knee-rating system. RESULTS: The average maximum degree of flexion increased from 27 degrees preoperatively to 115 degrees at the time of the most recent follow-up (p < 0.001). According to the criteria of Judet, the result was excellent for sixteen knees, good for five, and fair for one. The average Hospital for Special Surgery knee score improved from 74 points preoperatively to 94 points at the time of the most recent follow-up (p < 0.001). A superficial wound infection occurred in one patient. Only one patient had a persistent 15 degrees extension lag. CONCLUSIONS: This mini-invasive operation for the severely arthrofibrotic knee can be used to increase the range of motion and enhance functional outcome.

A new treatment strategy for severe arthrofibrosis of the knee. A review of twenty-two cases.

BACKGROUND: To reduce the morbidity of traditional quadricepsplasty for the treatment of severe arthrofibrosis of the knee, we instituted a treatment regimen consisting of an initial extra-articular mini-invasive quadricepsplasty and subsequent intra-articular arthroscopic lysis of adhesions during the same anesthesia session. The purpose of the present study was to determine the results of this technique. METHODS: From 1998 to 2001, twenty-two patients with severely arthrofibrotic knees were managed with this operative technique. The mean age of the patients at the time of the operation was thirty-seven years. After a mean duration of follow-up of forty-four months (minimum, twenty-four months), all patients were evaluated according to the criteria of Judet and The Hospital for Special Surgery knee-rating system. RESULTS: The average maximum degree of flexion increased from 27 degrees preoperatively to 115 degrees at the time of the most recent follow-up (p < 0.001). According to the criteria of Judet, the result was excellent for sixteen knees, good for five, and fair for one. The average Hospital for Special Surgery knee score improved from 74 points preoperatively to 94 points at the time of the most recent follow-up (p < 0.001). A superficial wound infection occurred in one patient. Only one patient had a persistent 15 degrees extension lag. CONCLUSIONS: This mini-invasive operation for the severely arthrofibrotic knee can be used to increase the range of motion and enhance functional outcome.

[Treatment of large bone defect of radius with vascularized tubulate periosteum graft and bone filling material in rabbits].

OBJECTIVE: To study the treatment efficacy of vascularized periosteum graft and bone filling material for long bone defect. METHODS: Forty young and forty adult rabbits were divided into four groups respectively according to the bone filling materials. A 3 cm long segment was removed from the middle part of the rabbit radius to make a bone defect model. The periosteum was reserved and restored to set up a vascularized tubulate periosteum graft. On the left side, autogenous bone graft, decalcified allograft, tricalcium phosphate, and hydroxyapatite were used to fill in the bone defect respectively; on the right side, no bone filling material was used as controls. The repairing effect of bone defect was evaluated by roentogenography, biomechanical, and histological methods. RESULTS: In young rabbits, bone defects on both sides healed in the 6th week after operation. The bending strength of radius in the tricalcium phosphate group and in the hydroxyapatite group were lower in the 12th week and there was significant difference when compared with autogenous bone graft group, decalcified allograft group and control group (P < 0.05). The repairing mechanism included intramembranous and endochondral ossification, and intramembranous ossification was prevalent. In the adult rabbits, the repairing rates of bone defect were 50% in the autogenous bone graft group, 40% in the decalcified allograft group, 30% in the tricalcium phosphate group and in the hydroxyapatite group and 42.5% in the control group, respectively. CONCLUSION: In young rabbits, large bone defect can be repaired with vascularized tubulate periosteum graft with or without the combining use of bone filling materials. The bone filling material which will be substituted slowly is disadvantageous to the recovery of bone strength. In adult rabbits, vascularized tubulate periosteum graft combined with bone filling materials can not repair the large bone defect effectively.

[Arthroscopic treatment of tibial eminence fracture with figure-of-eight suture fixation technique].

OBJECTIVE: To introduce the arthroscopic technique of figure-of-eight suture fixation for tibial eminence fracture, and to report its clinical results. METHODS: From January 1998 to June 2001, 21 cases of tibial eminence fracture were treated arthroscopically with figure-of-eight suture fixation technique. Active rehabilitation began one week after operation. The patients were followed up 6-24 months. The reduction and union of fracture, knee laxity, range of motion, and total knee function were evaluated. RESULTS: All fracture healed without displacement six weeks after operation. Three months postoperatively, no knee laxity or instability was detected in all patients; full range of motion of the affected knee returned in all patients when compared with the normal side. Six months postoperatively, the Lysholm knee score was 93.4 +/- 2.7. CONCLUSION: Arthroscopic treatment of tibial eminence fracture with figure-of-eight suture fixation technique is reliable for fracture reduction, fixation and early mobilization. Arthroscopy is conducive to diagnoses and treatment of associated knee arthropathy, reduces the morbidity associated with arthrotomy, and restores knee function to the greatest extent when combined with figure-of-eight suture fixation techniques.

[Clinical study on surgical repair of acute acromioclavicular dislocation by modified Weaver-Dunn technique].

OBJECTIVE: To investigate the clinical value of modified Weaver-Dunn technique in repair of acute acromioclavicular dislocation. METHODS: From January 1993 to December 1998, 18 cases of acromioclavicular dislocation were treated by modified Weaver-Dunn technique, and other 17 cases of the same suffering were treated by tension band fixation of the acromioclavicular joints. All of the patients were followed up for 12-36 months before clinical evaluation of the function of shoulder joints, according to University of Pennsylvanian Shoulder Score System. RESULTS: In short term, the shoulder joints recovered much more rapidly in the cases repaired by modified Weaver-Dunn technique; 12, 24 and 36 months after operation, the scores of the cases repaired by modified Weaver-Dunn technique were (189.7 +/- 6.7), (193.7 +/- 3.6) and (194.7 +/- 3.4) respectively according to the Shoulder Score System, while those of the cases treated by tension band fixation were (167.3 +/- 7.8), (170.2 +/- 6.3) and (165.6 +/- 5.9) respectively. The above data indicated that there was significant difference between two groups (P < 0.05). CONCLUSION: The modified Weaver-Dunn technique was a better surgical approach than tension band fixation for repair of acute acromioclavicular dislocation.