Background: Several studies have investigated the morphological risk factors contributing to posterior cruciate ligament (PCL) injury. However, no study has focused on the injury patterns of intrasubstance tears or tibial avulsion fractures in relation to morphologies and regional bone quality. This study aimed to investigate the impact of the knee morphology and regional bone quality of the proximal tibia on the PCL injury pattern. Methods: This retrospective study compared the radiological features of 76 patients with PCL injuries (PI group) and 76 matched patients with normal PCL (control group). The PI group was divided into 2 subgroups: PCL avulsion fracture (PAF subgroup; n = 43) and PCL intrasubstance tear (PIT subgroup; n = 33). Measurements included the coronal notch width index, coronal tibial slope, medial and lateral posterior tibial slopes, and medial tibial depth. Three Hounsfield unit average measurements were taken from the proximal tibia around the PCL insertion site to create a summative measure of overall bone quality. Results: The medial tibial depth and coronal notch width index were significantly lower in the PI group than those in the control group (medial tibial depth: 2.04 ± 0.77 vs. 3.02 ± 1.04, p = 0.017; coronal notch width index: 0.21 ± 0.03 vs. 0.24 ± 0.03, p = 0.041). In the subgroup analysis, medial tibial depth and Hounsfield unit were significantly lower in the PAF subgroup than in the PIT subgroup (medial tibial depth: 1.74 ± 0.66 vs. 2.43 ± 0.77, p = 0.008, Hounsfield unit: 89.48 ± 31.73 vs. 120.15 ± 29.24, p = 0.004). Binary logistic regression analysis showed that medial tibial depth (odds ratio [OR], 0.161; p < 0.001) and Hounsfield unit (OR, 0.950;p < 0.001) were independent risk factors for PCL tibial avulsion fractures. Conclusions Lower notch width index and medial tibial depth are associated with PCL injuries. Shallower medial tibial depth and lower Hounsfield unit measurements around the PCL insertion site were associated with an increased incidence of PCL avulsion fractures. These findings may assist clinicians in identifying patients at risk of distinct PCL injury patterns.

Background: The nipple is a potential source of pathogens because its lactiferous ducts act as direct conduits from the nipple–areolar complex to the breast parenchyma. Our previous studies identified breast microbiota as a factor in postoperative complications following immediate breast reconstruction using silicone implants and acellular dermal matrix. This study aimed to investigate the correlation between preoperative nipple swab microbiota and the incidence of surgical site infections (SSIs) after autologous breast reconstruction. Methods: We conducted a retrospective chart review of patients who underwent autologous breast reconstruction following total mastectomy. Preoperative nipple swab cultures were obtained. Patient demographics, surgical characteristics, and complication rates were compared between culture-positive and culture-negative groups. Microbiological data, including antibiotic‑resistance profiles, were collected. Results: Among 39 reconstructed breasts, 18 (46.9%) had positive preoperative nipple cultures. The mean duration of drain placement was significantly longer in the culture‑positive group (14.39±3.96 days) than in the culture‑negative group (12.14±2.76 days, P=0.045). Methicillin‑susceptible Staphylococcus epidermidis accounted for 55.0% of isolates. Of the four SSIs observed, three occurred in patients with positive preoperative cultures. Conclusions Although pathogen strains differed between preoperative and postoperative settings, obtaining preoperative nipple microflora cultures and determining antibiotic‑resistance profiles can guide immediate antibiotic selection for SSIs and enhance postoperative management.

Background: Several studies have investigated the morphological risk factors contributing to posterior cruciate ligament (PCL) injury. However, no study has focused on the injury patterns of intrasubstance tears or tibial avulsion fractures in relation to morphologies and regional bone quality. This study aimed to investigate the impact of the knee morphology and regional bone quality of the proximal tibia on the PCL injury pattern. Methods: This retrospective study compared the radiological features of 76 patients with PCL injuries (PI group) and 76 matched patients with normal PCL (control group). The PI group was divided into 2 subgroups: PCL avulsion fracture (PAF subgroup; n = 43) and PCL intrasubstance tear (PIT subgroup; n = 33). Measurements included the coronal notch width index, coronal tibial slope, medial and lateral posterior tibial slopes, and medial tibial depth. Three Hounsfield unit average measurements were taken from the proximal tibia around the PCL insertion site to create a summative measure of overall bone quality. Results: The medial tibial depth and coronal notch width index were significantly lower in the PI group than those in the control group (medial tibial depth: 2.04 ± 0.77 vs. 3.02 ± 1.04, p = 0.017; coronal notch width index: 0.21 ± 0.03 vs. 0.24 ± 0.03, p = 0.041). In the subgroup analysis, medial tibial depth and Hounsfield unit were significantly lower in the PAF subgroup than in the PIT subgroup (medial tibial depth: 1.74 ± 0.66 vs. 2.43 ± 0.77, p = 0.008, Hounsfield unit: 89.48 ± 31.73 vs. 120.15 ± 29.24, p = 0.004). Binary logistic regression analysis showed that medial tibial depth (odds ratio [OR], 0.161; p < 0.001) and Hounsfield unit (OR, 0.950;p < 0.001) were independent risk factors for PCL tibial avulsion fractures. Conclusions Lower notch width index and medial tibial depth are associated with PCL injuries. Shallower medial tibial depth and lower Hounsfield unit measurements around the PCL insertion site were associated with an increased incidence of PCL avulsion fractures. These findings may assist clinicians in identifying patients at risk of distinct PCL injury patterns.

Background: The nipple is a potential source of pathogens because its lactiferous ducts act as direct conduits from the nipple–areolar complex to the breast parenchyma. Our previous studies identified breast microbiota as a factor in postoperative complications following immediate breast reconstruction using silicone implants and acellular dermal matrix. This study aimed to investigate the correlation between preoperative nipple swab microbiota and the incidence of surgical site infections (SSIs) after autologous breast reconstruction. Methods: We conducted a retrospective chart review of patients who underwent autologous breast reconstruction following total mastectomy. Preoperative nipple swab cultures were obtained. Patient demographics, surgical characteristics, and complication rates were compared between culture-positive and culture-negative groups. Microbiological data, including antibiotic‑resistance profiles, were collected. Results: Among 39 reconstructed breasts, 18 (46.9%) had positive preoperative nipple cultures. The mean duration of drain placement was significantly longer in the culture‑positive group (14.39±3.96 days) than in the culture‑negative group (12.14±2.76 days, P=0.045). Methicillin‑susceptible Staphylococcus epidermidis accounted for 55.0% of isolates. Of the four SSIs observed, three occurred in patients with positive preoperative cultures. Conclusions Although pathogen strains differed between preoperative and postoperative settings, obtaining preoperative nipple microflora cultures and determining antibiotic‑resistance profiles can guide immediate antibiotic selection for SSIs and enhance postoperative management.

Background: Several studies have investigated the morphological risk factors contributing to posterior cruciate ligament (PCL) injury. However, no study has focused on the injury patterns of intrasubstance tears or tibial avulsion fractures in relation to morphologies and regional bone quality. This study aimed to investigate the impact of the knee morphology and regional bone quality of the proximal tibia on the PCL injury pattern. Methods: This retrospective study compared the radiological features of 76 patients with PCL injuries (PI group) and 76 matched patients with normal PCL (control group). The PI group was divided into 2 subgroups: PCL avulsion fracture (PAF subgroup; n = 43) and PCL intrasubstance tear (PIT subgroup; n = 33). Measurements included the coronal notch width index, coronal tibial slope, medial and lateral posterior tibial slopes, and medial tibial depth. Three Hounsfield unit average measurements were taken from the proximal tibia around the PCL insertion site to create a summative measure of overall bone quality. Results: The medial tibial depth and coronal notch width index were significantly lower in the PI group than those in the control group (medial tibial depth: 2.04 ± 0.77 vs. 3.02 ± 1.04, p = 0.017; coronal notch width index: 0.21 ± 0.03 vs. 0.24 ± 0.03, p = 0.041). In the subgroup analysis, medial tibial depth and Hounsfield unit were significantly lower in the PAF subgroup than in the PIT subgroup (medial tibial depth: 1.74 ± 0.66 vs. 2.43 ± 0.77, p = 0.008, Hounsfield unit: 89.48 ± 31.73 vs. 120.15 ± 29.24, p = 0.004). Binary logistic regression analysis showed that medial tibial depth (odds ratio [OR], 0.161; p < 0.001) and Hounsfield unit (OR, 0.950;p < 0.001) were independent risk factors for PCL tibial avulsion fractures. Conclusions Lower notch width index and medial tibial depth are associated with PCL injuries. Shallower medial tibial depth and lower Hounsfield unit measurements around the PCL insertion site were associated with an increased incidence of PCL avulsion fractures. These findings may assist clinicians in identifying patients at risk of distinct PCL injury patterns.

Background: The nipple is a potential source of pathogens because its lactiferous ducts act as direct conduits from the nipple–areolar complex to the breast parenchyma. Our previous studies identified breast microbiota as a factor in postoperative complications following immediate breast reconstruction using silicone implants and acellular dermal matrix. This study aimed to investigate the correlation between preoperative nipple swab microbiota and the incidence of surgical site infections (SSIs) after autologous breast reconstruction. Methods: We conducted a retrospective chart review of patients who underwent autologous breast reconstruction following total mastectomy. Preoperative nipple swab cultures were obtained. Patient demographics, surgical characteristics, and complication rates were compared between culture-positive and culture-negative groups. Microbiological data, including antibiotic‑resistance profiles, were collected. Results: Among 39 reconstructed breasts, 18 (46.9%) had positive preoperative nipple cultures. The mean duration of drain placement was significantly longer in the culture‑positive group (14.39±3.96 days) than in the culture‑negative group (12.14±2.76 days, P=0.045). Methicillin‑susceptible Staphylococcus epidermidis accounted for 55.0% of isolates. Of the four SSIs observed, three occurred in patients with positive preoperative cultures. Conclusions Although pathogen strains differed between preoperative and postoperative settings, obtaining preoperative nipple microflora cultures and determining antibiotic‑resistance profiles can guide immediate antibiotic selection for SSIs and enhance postoperative management.

Background: Several studies have investigated the morphological risk factors contributing to posterior cruciate ligament (PCL) injury. However, no study has focused on the injury patterns of intrasubstance tears or tibial avulsion fractures in relation to morphologies and regional bone quality. This study aimed to investigate the impact of the knee morphology and regional bone quality of the proximal tibia on the PCL injury pattern. Methods: This retrospective study compared the radiological features of 76 patients with PCL injuries (PI group) and 76 matched patients with normal PCL (control group). The PI group was divided into 2 subgroups: PCL avulsion fracture (PAF subgroup; n = 43) and PCL intrasubstance tear (PIT subgroup; n = 33). Measurements included the coronal notch width index, coronal tibial slope, medial and lateral posterior tibial slopes, and medial tibial depth. Three Hounsfield unit average measurements were taken from the proximal tibia around the PCL insertion site to create a summative measure of overall bone quality. Results: The medial tibial depth and coronal notch width index were significantly lower in the PI group than those in the control group (medial tibial depth: 2.04 ± 0.77 vs. 3.02 ± 1.04, p = 0.017; coronal notch width index: 0.21 ± 0.03 vs. 0.24 ± 0.03, p = 0.041). In the subgroup analysis, medial tibial depth and Hounsfield unit were significantly lower in the PAF subgroup than in the PIT subgroup (medial tibial depth: 1.74 ± 0.66 vs. 2.43 ± 0.77, p = 0.008, Hounsfield unit: 89.48 ± 31.73 vs. 120.15 ± 29.24, p = 0.004). Binary logistic regression analysis showed that medial tibial depth (odds ratio [OR], 0.161; p < 0.001) and Hounsfield unit (OR, 0.950;p < 0.001) were independent risk factors for PCL tibial avulsion fractures. Conclusions Lower notch width index and medial tibial depth are associated with PCL injuries. Shallower medial tibial depth and lower Hounsfield unit measurements around the PCL insertion site were associated with an increased incidence of PCL avulsion fractures. These findings may assist clinicians in identifying patients at risk of distinct PCL injury patterns.

Objective: This study aimed to assess the degree of interest in robot-assisted spine surgery (RASS) among residents and to investigate the learning curve for beginners performing robotic surgery. Methods: We conducted a survey to assess awareness and interest in RASS among young neurosurgery residents. Subsequently, we offered a hands-on training program using a dummy to educate one resident. After completing the program, the trained resident performed spinal fusion surgery with robotic assistance under the supervision of a mentor. The clinical outcomes and learning curve associated with robotic surgery were then analyzed. Results: Neurosurgical residents had limited opportunities to participate in spinal surgery during their training. Despite this, there was a significant interest in the emerging field of robotic surgery. A trained resident performed RASS under the supervision of a senior surgeon. A total of 166 screw insertions were attempted in 28 patients, with 2 screws failing due to skiving. According to the Gertzbein-Robbins classification, 85.54% of the screws were rated as grade A, 11.58% as grade B, 0.6% as grade C, and 1.2% as grade D. The clinical acceptance rate was approximately 96.99%, which is comparable to the results reported by senior experts and time per screw statistically significantly decreased as experience was gained. Conclusion RASS can be performed with high accuracy within a relatively short timeframe, if residents receive adequate training.

Purpose: The increase in thyroid cancer incidence has inevitably led to an increase in thyroid cancer surgeries. This meta-regression analysis aimed to determine if the rate of post-thyroidectomy complications changes by year. Materials and Methods: PubMed and Embase databases were used to perform a systematic literature search of studies published from January 1, 2005, using the keywords “thyroidectomy” and “complication.” A meta-regression was performed for post-thyroidectomy hypocalcemia and bleeding. Results: This meta-analysis included 25 studies involving 927751 individuals. Through the years of publications in this study, there was no significant difference in the proportion of post-thyroidectomy hypocalcemia and bleeding (p=0.9978, 0.6393). Conclusion Although the number of thyroid surgeries has recently increased, the incidence of post-thyroidectomy hypocalcemia and bleeding did not significantly increase.

OBJECTIVES: The escalating burden of cardiovascular disease (CVD) is a critical public health issue worldwide. CVD, especially acute myocardial infarction (AMI) and stroke, is the leading contributor to morbidity and mortality in Korea. We aimed to develop algorithms for identifying AMI and stroke events from the National Health Insurance Service (NHIS) database and validate these algorithms through medical record review. METHODS: We first established a concept and definition of “hospitalization episode,” taking into account the unique features of health claims-based NHIS database. We then developed first and recurrent event identification algorithms, separately for AMI and stroke, to determine whether each hospitalization episode represents a true incident case of AMI or stroke. Finally, we assessed our algorithms’ accuracy by calculating their positive predictive values (PPVs) based on medical records of algorithm- identified events. RESULTS: We developed identification algorithms for both AMI and stroke. To validate them, we conducted retrospective review of medical records for 3,140 algorithm-identified events (1,399 AMI and 1,741 stroke events) across 24 hospitals throughout Korea. The overall PPVs for the first and recurrent AMI events were around 92% and 78%, respectively, while those for the first and recurrent stroke events were around 88% and 81%, respectively. CONCLUSIONS We successfully developed algorithms for identifying AMI and stroke events. The algorithms demonstrated high accuracy, with PPVs of approximately 90% for first events and 80% for recurrent events. These findings indicate that our algorithms hold promise as an instrumental tool for the consistent and reliable production of national CVD statistics in Korea.