Sticky and Strain-Gradient Artificial Epineurium for Sutureless Nerve Repair in Rodents and Nonhuman Primates.

The need for the development of soft materials capable of stably adhering to nerve tissues without any suturing followed by additional damages is at the fore at a time when success in postoperative recovery depends largely on the surgical experience and/or specialized microsuturing skills of the surgeon. Despite fully recognizing such prerequisite conditions, designing the materials with robust adhesion to wet nerves as well as acute/chronic anti-inflammation remains to be resolved. Herein, a sticky and strain-gradient artificial epineurium (SSGAE) that overcomes the most critically challenging aspect for realizing sutureless repair of severely injured nerves is presented. In this regard, the SSGAE with a skin-inspired hierarchical structure entailing strain-gradient layers, anisotropic Janus layers including hydrophobic top and hydrophilic bottom surfaces, and synergistic self-healing capabilities enables immediate and stable neurorrhaphy in both rodent and nonhuman primate models, indicating that the bioinspired materials strategy significantly contributes to translational medicine for effective peripheral nerve repair.

Risk Factors of Flexor Tendon Rupture After ORIF of Distal Radius Fracture.

OBJECTIVES: To analyze the risk factors associated with postoperative flexor tendon rupture, after a volar plate fixation of distal radius fractures. DESIGN: Retrospective observational case-control study. SETTING: Tertiary Care University Hospital in the Republic of Korea (2009-2020). PATIENTS: Sixteen referred patients were treated for flexor tendon rupture, following previously performed volar plating of distal radius fractures at other institutions. 16 patients were randomly selected from our database as controls, and were matched based on the Soong grade of the case group. INTERVENTION: Not applicable. MAIN OUTCOME MEASUREMENTS: Radial tilt and radial height were measured on anteroposterior radiographs. The volar tilt, tear drop angle, carpal translation, and Soong grade were measured in a lateral view. RESULTS: Quantitative measurements of the volar tilt, carpal translation, and tear drop angle were positively correlated with the flexor tendon rupture. The mean volar tilt and tear drop angle in the tendon rupture group were significantly smaller than those in the control group. The mean carpal translation in the tendon rupture group was significantly greater than that in the control group. CONCLUSIONS: This study demonstrated that volar tilt, carpal translation, and tear drop angle are significant risk factors for flexor tendon rupture, especially for plates placed at Soong grade 1 or 2. We suggest that the potential for tendon rupture because of incomplete reduction of the distal radius fracture along with implant prominence volar to the watershed line aggravates flexor tendon irritation at the distal edge of the plate because of distorted flexor tendon paths. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Clinical Outcomes of Arthroscopic One-Tunnel Triangular Fibrocartilage Complex Transosseous Suture Repair Are Not Diminished in Cases of Ulnar Styloid Process Fracture Nonunion.

PURPOSE: To determine whether clinical outcomes of arthroscopic one-tunnel wrist triangular fibrocartilage complex (TFCC) transosseous suture repair are not diminished in cases of ulnar styloid process fracture nonunion (USPFN). METHODS: Patients who underwent arthroscopic 1-tunnel transosseous suture repair of Palmer 1B foveal TFCC tear (with/without superficial fiber tear; Atzei class 2 or 3 TFCC tear) from 2015 to 2020 were retrospectively reviewed. Group I was the TFCC foveal tear repair group with USPFN. Group II was the TFCC foveal tear repair group without USPFN. In group I, no additional treatment for USPFN was made. Functional preoperative and postoperative outcomes were compared by Modified Mayo Wrist Score (MMWS); Quick Disabilities of the Arm, Shoulder, and Hand (Quick-DASH) score; grip strength; pain visual analog scale (VAS); and distal radioulnar joint (DRUJ) stability. Wrist posteroanterior, lateral, and both oblique views of the wrist were used to assess the ulnar styloid process before and after operation. RESULTS: This study consisted of 66 patients: group I (n = 22) and group II (n = 44). No differences were found between the 2 groups preoperatively in MMWS, Quick-DASH, grip strength, and VAS (MMWS: P = .94, Quick-DASH: P = .23, grip strength: P = .69, VAS: P = .45). No differences were found between the 2 groups with respect to outcome measures postoperatively in MMWS, Quick-DASH, grip strength, and VAS (MMWS: P = .59, Quick DASH: P = .82, grip strength: P = .15, VAS: P = .84). All of the enrolled patients achieved restored function with negative ballottement test and maintained DRUJ stability on follow-up. Of the 22 USPFN cases in group I, 11 (50%) showed spontaneous union after transosseous TFCC foveal repair without any additional USPFN treatment. The proportion of patients achieving a minimal clinically important difference for the Quick-DASH was similar between the 2 groups. CONCLUSIONS: Although this current study has insufficient statistical power, the available data suggest that patients with TFCC foveal tear combined with USPFNs treated with arthroscopic transosseous repair surgery could experience similar functional improvement compared with those with TFCC foveal tear without USPFNs. The presence of USPFN accompanied by Palmer 1B type TFCC foveal tear may not affect the clinical results, including MMWS, Quick-DASH, grip strength, VAS, and DRUJ stability of patients who undergo arthroscopic 1-tunnel transosseous suture repair. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Development of a regenerative porous PLCL nerve guidance conduit with swellable hydrogel-based microgrooved surface pattern via 3D printing.

Peripheral nerve injury causes severe loss of motor and sensory functions, consequently increasing morbidity in affected patients. An autogenous nerve graft is considered the current gold standard for reconstructing nerve defects and recovering lost neurological functions; however, there are certain limitations to this method, such as limited donor nerve supply. With advances in regenerative medicine, recent research has focused on the fabrication of tissue-engineered nerve grafts as promising alternatives to the autogenous nerve grafts. In this study, we designed a nerve guidance conduit using an electrospun poly(lactide-co-ε-caprolactone) (PLCL) membrane with a visible light-crosslinked gelatin hydrogel. The PLCL nanoporous membrane with permeability served as a flexible and non-collapsible epineurium for the nerve conduit; the inner-aligned gelatin hydrogel paths were fabricated via 3D printing and a photocrosslinking system. The resultant gelatin hydrogel with microgrooved surface pattern was established as a conducting guidance path for the effective regeneration of axons and served as a reservoir that can incorporate and release bioactive molecules. From in vivo performance tests using a rat sciatic nerve defect model, our PLCL/gelatin conduit demonstrated successful axonal regeneration, remyelination capacities and facilitated functional recovery. Hence, the PLCL/gelatin conduit developed in this study is a promising substitute for autogenous nerve grafts. STATEMENT OF SIGNIFICANCE: Nerve guidance conduits (NGCs) are developed as promising recovery techniques for bridging peripheral nerve defects. However, there are still technological limitations including differences in the structures and components between natural peripheral nerve and NGCs. In this study, we designed a NGC composed of an electrospun poly(lactide-co-ε-caprolactone) (PLCL) membrane and 3D printed inner gelatin hydrogel to serve as a flexible and non-collapsible epineurium and a conducting guidance path, respectively, to mimic the fascicular structure of the peripheral nerve. In particular, in vitro cell tests clearly showed that gelatin hydrogel could guide the cells and function as a reservoir that incorporate and release nerve growth factor. From in vivo performance tests, our regenerative conduit successfully led to axonal regeneration with effective functional recovery.

The Effect of Smartphone App-Use Patterns on the Performance of Professional Golfers.

Smartphone app-use patterns will predict professional golfers' athletic performance, and the use time of serious apps would be associated with improved performance. This longitudinal 4-week observation of 79 professional golfers assessed golf handicaps and smartphone app-use patterns at the start of the Korean professional golf season and 2 and 4 weeks later. We classified use as social networking, entertainment, serious apps, and others. Use time of entertainment apps increased for non-improved golfers but did not change for improved golfers. Use time of serious apps increased for improved golfers and decreased for non-improved ones. Changes in golf handicaps were positively correlated with changes in entertainment app use time and negatively correlated with changes in serious app use time. Professional golfers' sports performance was not associated with smartphone use time but was with the smartphone app type. The management of smartphone app-use patterns is important for professional golfers' performance.

Influence of TFCC foveal tear on the location of lunate chondromalacia in ulnar impaction syndrome.

OBJECTIVE: The purpose of this study was to identify the location of lunate chondromalacia and to compare the difference in location according to presence or absence of triangular fibrocartilage complex (TFCC) foveal tear, which induces distal radioulnar joint (DRUJ) instability. METHODS: We performed a retrospective study of 97 patients (102 wrists) who were diagnosed with and treated for idiopathic ulnar impaction syndrome (UIS) between 2014 and 2018. Subjects were divided into two groups according to presence or absence of TFCC foveal tear with DRUJ instability. Group I had UIS without a TFCC foveal tear (52 wrists, mean age of 43.2 years), while Group II had UIS with a TFCC foveal tear (50 wrists, mean age of 45.3 years). There was no significant difference in age, sex, or duration of symptoms between the two groups. All patients underwent wrist MR Arthrography (MRA) in the same gantry, and all scanned coronal sections of the lunate were standardized into 10 slices, including the whole anteroposterior width of the lunate. Each slice was sequentially numbered from dorsal to volar side, and the location of chondromalacia was marked in each numbered section. Radiological parameters including ulnar variance and ulnolunate distance (ULD), which indicated the distance between the ulnar head and lunate, were measured in the wrist series. RESULTS: The most frequent location of lunate chondromalacia was slightly to the volar side of the lunate in both groups. Group I showed a higher frequency of chondromalacia in the volar side of the lunate. In Group II, chondromalacia was identified with high frequency not only on the volar side of the lunate but also on the dorsal side. In other words, Group II showed broader chondromalacia in the lunate. There was no significant difference in ulnar variance (Group I, 3.19 ± 1.42 mm; Group II, 2.76 mm ± 1.67 mm) or ulnolunate distance (Group I, 1.66 ± 0.94 mm; Group II, 2.05 mm ± 0.87 mm). The average ULD decreased during radial deviation but increased during ulnar deviation. CONCLUSION: This study showed that lunate chondromalacia associated with idiopathic ulnar impaction syndrome occurs more frequently on the volar side of the lunate. Also, TFCC foveal tear, which causes DRUJ instability, leads to broader lunate chondromalacia in idiopathic ulnar impaction syndrome. Therefore, further analysis of the pattern of lunate chondromalacia can provide a clue for DRUJ instability.

The Comparison of Perfectionism and Commitment between Professional and Amateur Golfers and the Association between Perfectionism and Commitment in the Two Groups.

This study investigated differences in perfectionist traits and commitment between professional and amateur golfers, as well as correlations among perfectionist traits, commitment, and golf handicap. Using simple random sampling, 486 professional golfers (mean age = 22.1 ± 3.0, 52.1% female) and 233 amateur golfers (mean age = 44.8 ± 10.2, 55.8% female) were recruited and assessed using the Multidimensional Perfectionism Scale (MPS) and Expansion of Sports Commitment Model (ESCM). An ANCOVA, controlling for age, golf career length, and training time, revealed lower MPS self-oriented scores (10.3%; F = 8.9, p < 0.01; effect size [ES] = 0.498) and higher ESCM-Cognition (12.6%; F = 9.4, p < 0.01; ES = 0.691) and ESCM-Behavior (9.4%; F = 4.6, p = 0.03; ES = 0.479) scores in professional golfers than in amateur golfers. In partial correlations controlling for age, golf career length, and training time, professional golfers' MPS scores were negatively associated with ESCM-Cognition scores (r = -0.30, p < 0.001). Professional golfers' mean golf handicap was positively correlated with MPS total (r = 0.33, p < 0.01). Altogether, golfers seeking to attain high levels of performance must consider the mental aspect of golfing and find ways to maximize commitment levels while minimizing perfectionist traits.

Comparison of Psychological and Cognitive Characteristics between Professional Internet Game Players and Professional Baseball Players.

The esports industry is increasing in popularity and is now played at the professional level. We hypothesized that esports players may have a significant advantage over the general population in terms of psychological and cognitive characteristics, which may be similar to that of professional baseball players. We recruited three participant groups: esports players (n = 55), pro-baseball players (n = 57), and age- and sex-matched healthy comparison subjects (n = 60). We assessed psychological status using the Korean versions of Temperament and Character Inventory and State and Trait Anxiety Inventory and cognitive functions using the modified Tower of London, Emotional Perception, and Mental Rotation tests. Esports players had similar psychological characteristics to pro-baseball players (higher novelty seeking [p < 0.01 *, ŋ = 0.818], self-directedness [p < 0.01 *, ŋ = 0.757], and self-transcendence scores [p < 0.01 *, ŋ = 0.853], and decreased state anxiety scores [p < 0.01 *, ŋ = 0.808]), which differed from those of the general population. However, esports players showed higher working memory [p < 0.01 *, ŋ = 0.823] and slower emotional perception than pro-baseball players [p < 0.01 *, ŋ = 0.812]. In conclusion, esports and pro-baseball players had similar psychological but different cognitive characteristics.

Preoperative Supine Radiographs Are More Accurate Than Standing Radiographs for Preoperative Planning in Medial Open-Wedge High Tibial Osteotomy.

PURPOSE: To verify the accuracy of supine nonweight-bearing radiography versus standing radiography in preoperative planning and to determine the predictors of unintended limb alignment correction in medial open-wedge high tibial osteotomy (OWHTO). METHODS: Consecutive patients who underwent medial OWHTO for medial osteoarthritis of the knee with varus alignment were retrospectively reviewed. The analyzed pre- and postoperative radiologic measurements included postoperative mechanical axis deviation (MAD) on standing whole-leg radiographs (WLRs), the predicted value of the postoperative MAD on the preoperative supine (predicted MADsupine) radiograph, and standing WLRs (predicted MADstand). Multiple linear regression analysis was used to identify variables predicting the postoperative MAD and unintended MADstand correction, defined as the difference between predicted MADstand and postoperative MAD. RESULTS: Predicted MADsupine showed statistically greater reliability in predicting postoperative MAD than predicted MADstand (intraclass correlation coefficient, 0.82 vs 0.45). Postoperative MAD was correlated with the predicted MADsupine and the difference in hip-knee-ankle angle between preoperative standing and supine WLRs (ΔHKA anglestand-supine) (R =763, R2 = 0.582, adjusted R2 = 0.569, P < .001) and did not differ significantly from the predicted MADsupine, with a mean difference of 0.28% ± 5.11% (P = .656). The mean unintended MADstand correction was 6.52% ± 8.66%. The difference in preoperative MAD between standing and supine WLRs was a significant predictor for unintended MADstand correction (ß = -0.350, P = .004). CONCLUSIONS: Preoperative planning with supine WLRs can predict postoperative limb alignment in medial OWHTO more accurately than standing radiographs. The clinical significance of the ΔHKA anglestand-supine for the risk of overestimation of postoperative limb alignment might be low because of the low power in the prediction model and small value of the ΔHKA anglestand-supine. Preoperative soft-tissue laxity was significantly correlated with unintended correction of postoperative limb alignment resulting from preoperative planning with standing radiographs. LEVEL OF EVIDENCE: Level IV, retrospective comparative study.

Development and Verification of a Web Board Game Scale.

OBJECTIVE: Our previous study suggested that monitoring online board gamers may be an efficient approach to curb illegal gambling. We aimed to invent and validate a behavioral scale for assessing the risk of problematic web-based board gaming. METHODS: The sample included 300 Korean adults, representing a response rate of 3.1%. All participants were asked to complete a set of questionnaires, which included questions on demographic variables, patterns of online board gaming, and the web-based board game scale score. Exploratory factor analysis was performed to determine whether the items on the new behavioral scale would indicate a risk of pathologic web-based board gaming behavior. RESULTS: The internal consistency of the 17-item scale was high (Cronbach's α=0.89). The test-retest reliability of the 17-item scale in a randomly selected sample of 100 participants in 2 weeks was r=0.77 (p<0.001). The criterion-related validity based on a comparison of the total behavioral scale scores between the high-risk group and low-risk group was relatively high. The data obtained from the 300 participants were acceptable for a factor analysis. After removing 7 items from the 17-item scale, internal consistency (Cronbach's α) of the 10-item scale increased to 0.936. CONCLUSION: These results showed that the 10-item version of the scale appeared to be more valid than the 17-item version. We suggest that the 10-item web-based board game behavioral scale is a useful tool for assessing the risk of pathologic web-based board gaming.

Investigation of an emotion perception test using functional magnetic resonance imaging.

BACKGROUND AND OBJECTIVE: Patients with mood disorders are known to have an emotion recognition deficit in facial emotion processing. Emotion perception involves two systems of cognitive and affective processes associated with brain activation in the fusiform gyrus and prefrontal cortices. To overcome the limitations of existing emotion perception tests, we designed an emotion perception index to assess the individuals' mood status. METHODS: We selected 66 emotional faces (22 pleasant, 22 unpleasant, and 22 neutral) for the emotion perception test and recruited 40 healthy participants to verify the test. The participants completed a demographic data questionnaire and were administered the Beck Depressive Inventory (BDI). They were also scanned to assess the brain functional connectivity (FC) between seeds of the fusiform gyrus and other brain regions using resting-state functional magnetic resonance imaging (rs-fMRI). After rs-fMRI scanning, the participants were administered the emotion perception test on a computer. RESULTS: In response to 108 questions regarding emotional face differentiation, the study group showed an average correct-answer rate of 90.7 ±â€¯6.4% and a mean reaction time of 1.4 ±â€¯0.4 s. We created an emotion perception index from the calculation of correct rate, number of correct responses, and reaction time in response to 108 questions; the mean of the emotion perception index in the study group was 3.8 ±â€¯0.2. The emotion perception index was positively correlated with the BDI scores (r = 0.4, p = 0.01); further, it was positively correlated with the FC from the fusiform gyrus to the left superior frontal gyrus (FDRq < 0.01), left medial frontal gyrus (FDRq < 0.01), left frontal precentral gyrus (FDRq = 0.02), left insula (FDRq < 0.01), and left occipital cuneus (FDRq = 0.01). The FC from the fusiform gyrus to the left insula was positively correlated with the BDI scores (r = 0.59, p < 0.001). CONCLUSIONS: The emotion perception index designed in this study may correctly indicate the mood status of individuals. In addition, the emotion perception test was associated with brain FC from the fusiform gyrus to the frontal and insular cortices.

Patient Blood Management During Lumbar Spinal Fusion Surgery.

OBJECTIVE: Patient blood management (PBM) is defined as treatment of a patient who is at risk of transfusion to minimize the need for transfusion and improve the probability of an optimal clinical outcome. We performed the present study to examine the effects of PBM in spinal fusion surgery. METHODS: A total of 154 patients who had undergone 1- and 2-level posterior lumbar interbody fusion for degenerative lumbar disease were included. We retrospectively reviewed the data from 101 patients from 2012 to 2016 as the pre-PBM group. We recruited 53 patients from 2017 to 2018 for the post-PBM group. Intravenous iron was administered 2-4 weeks before surgery, and intravenous tranexamic acid was administered intraoperatively in the post-PBM group. The primary outcome was the reduction of hemoglobin (Hb). The secondary outcomes included perioperative blood loss, Hemovac drain output, postoperative transfusion, complications, and length of hospital stay. RESULTS: Intravenous iron was administered 17.4 days before surgery in the post-PBM group. The reduction in Hb was not significantly different statistically between the 2 groups (3.06 vs. 3.33 g/dL; P > 0.05). Of the 101 patients in the pre-PBM group, 24 (24%) underwent transfusion. In contrast, no patient in the post-PBM group had required a transfusion (P < 0.001). The average hospital stay was 10.15 days in the pre-PBM group and 8.33 days in the post-PBM group (P = 0.02). The average operative time was 146 minutes in the pre-PBM group and 133 minutes in the post-PBM group (P = 0.03). The Hb decrease and total Hemovac drain output did not differ significantly between the 2 groups. CONCLUSIONS: Implementation of PBM is an effective strategy for reducing the rate of transfusion in patients undergoing lumbar spinal fusion surgery without significant complications.