Transcranial motor-evoked potentials disappear with pons transection.

Motor-evoked potential (MEP) monitoring by transcranial electrical stimulation (TES) is important for intraoperative motor function assessment in neurosurgery; however, false-negative results sometimes occur, and these findings should be interpreted with caution. Herein, we report an interesting MEP change resulting from a pons transection. The patient was a boy aged 5 years and 2 months. He underwent multiple craniotomies for cerebellar anaplastic ependymoma and was already paralyzed in the right upper and lower limbs. Therefore, we decided to remove the recurrent lesion from the left anterior pons. MEPs were recorded on both the right and left sides after the start of surgery but disappeared 1 h 30 min after the start of surgery in the TES on the operative side, even when the stimulation intensity was increased. The contralateral TES consistently recorded stable MEPs throughout the surgery. The tumor was completely resected on imaging. Immediately postoperatively, the patient experienced flaccid paralysis on the right side of the body, which recovered to preoperative levels over time. A transcranial MEP cannot be derived if the corticospinal tract is transected at the pons. Transcranial MEP findings may accurately reflect the corticospinal tract function if the injury is caudal to the pons.

Surgical treatment of interhemispheric arachnoid cysts.

OBJECTIVE: In children, interhemispheric arachnoid cysts (IHACs) are rare lesions often associated with corpus callosum dysgenesis. It is still controversial about surgical treatments for IHACs. We aim to report our experience with pediatric IHAC patients and evaluate surgical courses and neurological developments. METHODS: Pediatric IHACs treated between 2001 and 2021 were reviewed retrospectively. IHAC was observed until they represented rapid cyst enlargement or neurological symptoms. Cyst fenestration was done by microscope or endoscope, depending on the IHAC's location. Cyst size and corpus callosum dysgenesis were evaluated with neuroimaging. Neurological development was assessed from medical records at the last follow-up. RESULTS: Fifteen children received cyst fenestration surgery (mean age 11.4 months). Eleven patients (73.3%) under observation showed rapid cyst enlargement in a short period (median 5 months). Cysto-ventriculostomy (CVS) and cysto-cisternostomy (CCS) regressed the cyst size significantly (p = 0.003). The median follow-up duration was 51 months (range 14-178 months). Corpus callosum dysgenesis was observed in eleven patients (73.3%, complete = 5, partial = 6). Among eight patients (53.3%) having developmental delay, five patients (33.3%) showed speech delay, including one patient with intractable seizures. CONCLUSION: Pediatric IHACs frequently present within 1 year after birth, with rapid cyst enlargement. CVS and CCS were effective in regressing the cyst size. Corpus callosum dysgenesis accompanied by IHAC might have a risk of language achievement; however, development delay could rely on multifactorial features, such as epilepsy or other brain anomalies.

Coronal and sagittal alignment of ankle joint is significantly affected by high tibial osteotomy.

PURPOSE: Changes in coronal and sagittal alignment of the knee joint after HTO have been reported in several previous studies. However, only few of them investigated the changes only on coronal alignment of the ankle joint. The purpose of this study was to investigate changes in both coronal and sagittal alignment of the ankle joint after HTO. METHODS: 46 patients (49 cases) who underwent HTO were retrospectively analyzed. Preoperative and postoperative lower extremity scanogram and EOS imaging system were investigated. The hip-knee-ankle (HKA) angle, medial proximal tibial angle (MPTA), and knee tibia plafond angle (KTPA) were measured by scanogram to evaluate coronal alignment of the knee. Tibial anterior surface angle (TAS), talar tilt (TT), tibial plafond inclination (TPI), and ankle joint axis point on the weight-bearing-line (AAWBL) ratio were measured by scanogram to investigate coronal alignment of the ankle. Knee lateral ankle surface angle (KLAS) and tibial lateral surface angle (TLS) were measured by EOS to evaluate sagittal alignment of the ankle. RESULTS: Varus alignment of the knee was corrected by significant change of the HKA angle (5.8 ± 3.1° vs. - 2.1 ± 2.8°, p < 0.001), MPTA (85.7 ± 2.9° vs. 91.7 ± 3.3°, p < 0.001), and KTPA (5.0 ± 3.5° vs. - 2.1 ± 4.2°, p < 0.001) after HTO. Regarding the ankle coronal alignment, there was significant change in TPI (3.9 ± 3.4° vs. - 0.9 ± 3.8°, p < 0.001) and AAWBL ratio (45.5 ± 14.7% vs. 61.6 ± 13.3%, p < 0.001). In sagittal alignment of the ankle, KLAS (4.5 ± 3.1° vs. 7.7 ± 3.7°, p < 0.001) significantly increased. Among the variables, the amount of correction in AAWBL ratio (R = 0.608, p < 0.01) showed strongest relationship with tibial correction angle. CONCLUSION: Based on the present study, coronal and sagittal alignment of ankle joint was significantly affected by HTO. After HTO, AAWBL ratio increased due to lateralization of the ankle joint axis, and KLAS increased due to increased posterior tibial slope. LEVEL OF EVIDENCE: III.

Fabrication and Characterization of Three-Dimensional Microelectromechanical System Coaxial Socket Device for Semiconductor Package Testing.

With the continuous reduction in size and increase in density of semiconductor devices, there is a growing demand for contact solutions that enable high-speed testing in automotive, 5G, and artificial intelligence-based devices. Although existing solutions, such as spring pins and rubber sockets, have been effective in various applications, there is still a need for new solutions that accommodate fine-pitch, high-speed, and high-density requirements. This study proposes a novel three-dimensional microelectromechanical system spring structure coaxial socket for semiconductor chip package testing. The socket design incorporates impedance matching for high-speed testing and addresses the challenges of fine-pitch and high-density applications. Mechanical tests are conducted to evaluate the durability of the structure and electrical tests are performed to verify electrical characteristics by utilizing a vector network analyzer up to 60 GHz. Our results have revealed promising performance and will help in further optimizing the design for potential production in the field and industry.

Optimal ICG dosage of preoperative colonoscopic tattooing for fluorescence-guided laparoscopic colorectal surgery.

BACKGROUND: Indocyanine green (ICG) is a multifunctional dye used in tumor localization, tissue perfusion, and lymph node (LN) mapping during fluorescence-guided laparoscopic colorectal surgery. PURPOSE: This study aimed to establish the optimal protocol for preoperative endoscopic submucosal ICG injection to perform fluorescence lymph node mapping (FLNM), along with undisturbed fluorescent tumor localization and ICG angiography during a single surgery. METHODS: Colorectal cancer patients (n = 192) were enrolled from May 2017 to December 2019. Colonoscopic submucosal ICG injection was performed 12 to 18 h before surgery. ICG injection protocols were modified based on the total injected ICG (mg) and tattooing site number. The concentrations of ICG were gradually decreased from the standard dose (2.5 mg/ml) to the minimum dose (0.2 mg/ml). Successful FLNM (FLNM-s) was defined as distinct fluorescent LNs observed under NIR camera. The patient's age, sex, body mass index (BMI), stage, cancer location, obstruction, and laboratory findings were compared between the FLNM-s and failed FLNM (FLNM-f) groups to identify clinical and pathological factors that affect FLNM. RESULTS: In the ICG dose section of 0.5 to 1 mg, the success rate was highest within all functions including FLNM, fluorescent tumor localization, and ICG angiography. FLNM-s was related to ICG dose (0.5-1 mg), multiple submucosal injections, location of cancer, camera light source, and lower BMI. In the multivariate analysis, camera light source, non-obesity, and multiple injections were independent factors for FLNM-s). The mean total number of harvested LNs was significantly higher in the FLNM-s group than that in the FLNM-f group (p < 0.001). The number of metastatic lymph nodes was comparable between the two groups (p = 0.859). CONCLUSIONS: Preoperative, endoscopic submucosal ICG injection with dose range 0.5 to 1 mg would be optimal protocol for multifunctional ICG applications during fluorescence-guided laparoscopic colorectal surgery.

Hinge and floating decompressive craniotomy for infantile acute subdural hematoma: technical note.

Cranioplasty complications after decompressive craniectomy (DC) in infants are not fully recognized. We aimed to devise and assess the efficacy of a hinge and floating DC (HFDC) technique for treating infantile acute subdural hematoma. Five infants, aged 2-20 months, were included. Intracranial pressure was controlled below 20 mmHg, no additional surgery was required, and there was no incidence of surgical site infection or bone graft resorption.

Efficacy and safety of intraventricular fibrinolytic therapy for post-intraventricular hemorrhagic hydrocephalus in extreme low birth weight infants: a preliminary clinical study.

PURPOSE: To evaluate the efficacy and safety of our unique therapy for treating post-intraventricular hemorrhagic hydrocephalus (PIVHH) in low birth weight infants (LBWls) through an early stage fibrinolytic therapeutic strategy involving urokinase (UK) injection into the lateral ventricle, called the "Ventricular Lavage (VL) therapy." METHODS: Overall, 43 consecutive infants with PIVHH were included. Most were extremely LBWIs (n = 39). Other cases included very LBWIs (n = 2) and full-term infants (n = 2). VL therapy involved continuous external ventricular drainage (EVD) management using a very fine catheter and intermittent slow injection of 6000 IU of UK every 3-6 h to actively dissolve hematomas. RESULTS: Early EVD management (within 3 weeks of IVH onset) was performed in 25 infants, with combination VL therapy in 21 infants. Five initiated late EVD management (≥ 3 weeks after IVH onset); the remaining 13 were treated conservatively for several weeks, delaying surgical intervention. Eighteen of 21 (86%) infants who received VL therapy did not require permanent shunt surgery. There were no serious complications, including the absence of secondary hemorrhage and infection. Two-thirds of the infants treated in the late stages required permanent shunt, and various shunt-related complications frequently occurred. A good outcome occurred in 13/17 infants in the early treatment group, despite most subjects having an IVH grade IV, and in 6/15 in the late treatment group. CONCLUSIONS: Permanent shunt surgery needs were dramatically reduced following early VL therapy, and functional outcomes were favorable. VL therapy might be a promising strategy that could lead to the development of new treatments for PIVHH.

Combined Intravenous and Intraarticular Tranexamic Acid Does Not Offer Additional Benefit Compared with Intraarticular Use Alone in Bilateral TKA: A Randomized Controlled Trial.

BACKGROUND: Tranexamic acid (TXA) is efficacious for reducing blood loss and transfusion use in patients who undergo bilateral TKA, and it is administered intravenously alone, intraarticularly alone, or as a combination of these. However, it is unclear whether combined intravenous (IV) and intraarticular TXA offers any additional benefit over intraarticular use alone in patients undergoing bilateral TKA. QUESTIONS/PURPOSES: The purposes of our study was to determine (1) whether combined IV and intraarticular TXA reduces blood loss and blood transfusion use compared with intraarticular use alone and (2) whether the frequency of adverse events is different between these routes of administration in patients who undergo simultaneous or staged bilateral TKA. METHODS: Between April 2015 and May 2017, one surgeon performed 316 same-day bilateral TKAs and 314 staged bilateral TKAs. Of those, 98% of patients in each same-day TKA (310) and staged bilateral TKA (309) groups were eligible for this randomized trial and all of those patients agreed to participate and were randomized. The study included four groups: simultaneous TKA with intraarticular TXA only (n = 157), simultaneous TKA with IV and intraarticular TXA (n = 153), staged TKA with intraarticular TXA only (n = 156), and staged TKA with IV and intraarticular TXA (n = 155). There were no differences in demographic data among the intraarticular alone and IV plus intraarticular TXA groups of patients who underwent simultaneous or staged bilateral TKA in terms of age, proportion of female patients, BMI, or preoperative hematologic values. The primary outcome variables were total blood loss calculated based on patient blood volume and a drop in the hemoglobin level and administration of blood transfusion. The secondary outcomes of this study were a decrease in the postoperative hemoglobin level; the proportion of patients with a hemoglobin level lower than 7.0, 8.0, or 9.0 g/dL; and the frequencies of symptomatic deep vein thrombosis, symptomatic pulmonary embolism, wound complications, and periprosthetic joint infection. RESULTS: Total blood loss with intraarticular TXA alone in patients undergoing simultaneous bilateral TKA and those undergoing staged procedures was not different from the total blood loss with the combined IV plus intraarticular TXA regimen (1063 mL ± 303 mL versus 1004 mL ± 287 mL, mean difference 59 mL [95% CI -7 to 125]; p = 0.08 and 909 ml ± 283 ml versus 845 ml ± 278 ml; mean difference 64 mL [95% CI 1 to 127]; p = 0.046, respectively). The use of blood transfusions between intraarticular alone and combined IV and intraarticular TXA was also not different among patients undergoing simultaneous (0% [0 of 152] versus 1%; p = 0.149) and staged TKA (1% [1 of 155] versus 0% [0 of 153]; p = 0.98). Furthermore, the frequency of symptomatic thromboembolic events, wound complications, and periprosthetic joint infections was low, without any differences among the groups with the numbers available. CONCLUSION: Because there was no difference between intraarticular alone and combined intraarticular plus IV regimen of TXA administration, we recommend that IV and intraarticular TXA should not be used in combination. Moreover, other studies have found no differences between intraarticular and IV TXA used alone, and hence to avoid potential complications associated with systemic administration, we recommend that intraarticular alone is sufficient for routine TKA. LEVEL OF EVIDENCE: Level I, therapeutic study.

C2 extradural schwannoma compressing the dominant internal jugular vein: a case report.

We describe a rare case of extradural schwannoma in the upper cervical spine compressing the dominant internal jugular vein (IJV) presenting with atypical headaches. A 50-year-old woman complained of a subcutaneous neck mass associated with atypical headaches. Radiological examinations revealed the right IJV was compressed anteriorly by C2 extradural mass and occluded with markedly dilated collateral cerebral venous drainage through deep cervical veins. Subtotal removal was performed via the posterolateral approach and the atypical headaches resolved immediately. This case demonstrates that extradural schwannoma in the upper cervical spine could compress the IJV and manifest as cerebral venous circulation disturbances.

Unicompartmental knee arthroplasty, an enigma, and the ten enigmas of medial UKA.

Unicompartmental knee arthroplasty (UKA) is a bone- and ligament-sparing alternative to total knee arthroplasty in the patients with end-stage single-compartment degeneration of the knee. Despite being a successful procedure, the multiple advantages of UKA do not correlate with its usage, most likely due to the concerns regarding prosthesis survivability, patient selection, ideal bearing design, and judicious use of advanced technology among many others. Therefore, the purpose of this study is to review and summarize the debated literature and discuss the controversies as "Ten Enigmas of UKA."

Comparison of Intraoperative Sedation With Dexmedetomidine Versus Propofol on Acute Postoperative Pain in Total Knee Arthroplasty Under Spinal Anesthesia: A Randomized Trial.

BACKGROUND: In patients undergoing total knee arthroplasty under spinal anesthesia, we compared the postoperative analgesic effect of intraoperative sedation with dexmedetomidine versus propofol. We hypothesized that sedation with dexmedetomidine would result in lower postoperative opioid analgesic consumption than with propofol. METHODS: Forty-eight patients were enrolled and randomly assigned to either a dexmedetomidine group (n = 24), which received a loading dose of 1 µg/kg dexmedetomidine over 10 minutes, followed by a continuous infusion of 0.1-0.5 µg·kg·hour, or a propofol group (n = 24), which received a continuous infusion of propofol via a target-controlled infusion to maintain the effect-site concentration within a range of 0.5-2.0 µg/mL. The drug infusion rate was determined according to the sedation level, targeting a modified observer's assessment of alertness/sedation score of 3 or 4. The cumulative amounts of fentanyl administered via intravenous patient-controlled analgesia were recorded at 24 and 48 hours postoperatively (primary outcome). The postoperative numerical rating scale for pain was assessed at 6, 12, 24, and 48 hours (secondary outcome). The postoperative use of additional rescue analgesic (ketoprofen) and antiemetic drugs was also compared between the 2 groups at 24 and 48 hours. RESULTS: Dexmedetomidine significantly reduced postoperative fentanyl consumption (median [interquartile range]) during 0-24 hours (45 [30-71] vs 150 [49-248] µg, P = .004; median difference = -105 µg [99.98% CI, 210-7.5]), 24-48 hours (90 [45-143] vs 188 [75-266] µg, P = .005; median difference = -98 µg [99.98% CI, 195-45]), and 0-48 hours (135 [68-195] vs 360 [146-480] µg, P = .003; median difference = -225 µg [99.98% CI, 405-7.5]). The numerical rating scale (median [interquartile range]) was lower at 6 hours (1 [0-2] vs 2 [1-3], P = .003), 12 hours (1 [1-2] vs 3 [2-3], P < .001), 24 hours (1 [1-2] vs 3 [2-3], P < .001), and 48 hours (2 [2-3] vs 3 [3-4], P < .001) after surgery in the dexmedetomidine group compared to the propofol group. No significant intergroup differences were observed in the amount of rescue analgesics and antiemetics at 24 hours (P = .155 and P = .482) and 48 hours (P = .082 and P = .153) after surgery. CONCLUSIONS: Intraoperative dexmedetomidine sedation was associated with a small but clinically important reduction in postoperative opioid use after total knee arthroplasty.

Is lower tourniquet pressure during total knee arthroplasty effective? A prospective randomized controlled trial.

BACKGROUND: Higher tourniquet pressures may be associated with an increased risk of complications. We aimed to determine (1) whether a lower tourniquet pressure [systolic blood pressure (SBP) + 120 mmHg] is as effective as conventional tourniquet pressure (SBP + 150 mmHg) in providing a bloodless surgical field and decreasing blood loss, and (2) whether lowering the tourniquet pressure decreases tourniquet-related complications compared to conventional inflation pressure. METHODS: One hundred and sixty knees in 124 patients undergoing total knee arthroplasty (TKA) were randomly allocated to either conventional (n = 80) or lower inflation pressure group (n = 80). The quality of the initial surgical field and occurrence of intraoperative blood oozing, hemoglobin drop, drained volume and calculated blood loss were assessed as efficacy variables. Safety outcome variables included post-operative pain, tourniquet site skin problems (ecchymosis, bullae, skin necrosis), and other tourniquet-related complications such as nerve palsy, venous thromboembolism, and delayed rehabilitation. RESULTS: A comparable bloodless surgical field was successfully provided in both groups (100% vs. 99%, p = 1.000). One case in the conventional pressure group and two cases in the lower pressure group showed intraoperative blood oozing (p = 1.000), which was successfully controlled after an increase of 30 mmHg in the tourniquet inflation pressure. There was no difference in the hemoglobin drop, drained volume, and calculated blood loss. The two groups did not differ in any safety outcomes such as post-operative pain, thigh complications, and other tourniquet related complications. CONCLUSION: This study demonstrates that a tourniquet inflation pressure of 120 mmHg above the SBP is effective method during TKA. TRIAL REGISTRATION: The trial was with ClinicalTrials.gov ( NCT01993758 ) on November 25, 2013.

New mobile-bearing TKA with unique ball and socket post-cam mechanism offers similar function and stability with better prosthesis fit and gap balancing compared to an established fixed-bearing prosthesis.

PURPOSE: A mobile-bearing (MB) posterior-stabilized total knee arthroplasty (TKA) system with ball and socket post-cam mechanism has been developed with the aims of better prosthesis fit and enhanced stability. However, the data are limited to compare its clinical outcomes with an already established fixed-bearing (FB) implant design. METHODS: This is a prospective randomized study comparing 260 patients in the MB group and 133 patients in FB group with a minimum 2 years of follow-up. Intraoperative variables, post-operative functional outcomes and incidence of adverse events were compared. RESULTS: MB group showed better prosthesis fit as the incidence of over-hang of femoral component at junction (medial: 1% vs. 5% and lateral: 2% vs 4%, p < 0.001) and trochlea (medial: 2% vs 30%, p = 0.042 and lateral: 13% vs 21%, p = 0.015) was less than FB group. MB group also showed better gap balancing as the incidence of medio-lateral gap difference more than 2 mm was less in flexion (2.3% vs. 16%, p < 0.001) and extension (3.1% vs. 9.8%, p = 0.005). Post-operative functional outcomes and incidence of adverse events showed no difference between the two groups at 2 years. CONCLUSIONS: New MB design offers similar functional outcomes and stability along with better intraoperative prosthesis fit and gap balancing compared to an established fixed-bearing design. Hence, this new MB design could be an alternative prosthesis of choice for posterior-stabilized TKA. LEVEL OF EVIDENCE: I.

Comparison of the Inhibitory Activities of 5,6-Dihydroergosterol Glycoside α- and ß-Anomers on Skin Inflammation.

Chronic skin inflammatory diseases, such as atopic dermatitis, are associated with a dysfunctional skin barrier due to an increase in various inflammatory stimuli, for instance inflammatory cytokines and chemokines. In particular, CCL17 and CCL22 expression is increased in patients with chronic skin inflammation. In this study, we synthesized several α- and ß-anomers of dihydroergosterol (DHE)-glycosides and assessed their effects on CCL17 and CCL22 expression. We confirmed that the ß-anomers of DHE-glycosides were superior to α-anomers of DHE-glycosides in inhibiting CCL17 and CCL22 mRNA and protein expression. In addition, we determined that DHE-glycoside ß-anomers showed strong inhibitory activity towards pro-inflammatory cytokine mRNA and protein expression, including that of TNF-α, IL-6, and IL-1ß- in stimulated HaCaT cells. These results imply that DHE-glycoside α- and ß-anomers should be separated during synthesis of drugs for chronic skin inflammation. Our results also suggest that ß-anomers of DHE-glycosides may play an important role as new drugs for chronic skin inflammation because of their ability to inhibit the skin inflammatory biomarker proteins CCL17 and CCL22.

Temporal patterns of commonly used clinical outcome scales during a 5-year period after total knee arthroplasty.

BACKGROUND: It is not established beyond doubt whether improvements in functional outcome after total knee arthroplasty (TKA) are maintained in the long term. We therefore investigated the temporal patterns of functional outcome [using range of motion (ROM), American Knee Society (AKS) score, Western Ontario and McMaster Universities Arthritis Index (WOMAC) score, and 36-Item Short Form Health Survey (SF-36) score] over a 5-year period after uncomplicated TKA, and whether these patterns differed by implant type and patient age. MATERIALS AND METHODS: This prospective study evaluated 138 patients who underwent unilateral TKA with either a mobile-bearing (MB) or fixed-bearing (FB) posterior-stabilized prosthesis. An independent investigator evaluated the functional outcome at five time points: preoperatively and at 6-month, 1-year, 2-year, and 5-year follow-up. Differences in functional outcomes between adjacent time points were evaluated by mixed-effect model repeat measurement (MMRM). RESULTS: The different functional outcome scores showed improvement till 6 months-2 years, followed by a variable decline. In patients aged ≥ 68 years with an MB implant, most of the functional outcome scores declined between 2 and 5 years after variable initial improvement till 6 months-2 years, whereas the parameters plateaued after 2 years in those aged < 68 years and in older patients with an FB implant. CONCLUSIONS: A decline in function and pain relief occurs 2 years after TKA. This decline is more evident in older patients with an MB prosthesis. Based on these findings, we believe that use of MB implants in older patients (≥ 68 years) requires further investigation. LEVEL OF EVIDENCE: Level 3.

Intravenous Tranexamic Acid Reduces Postoperative Blood Loss After High Tibial Osteotomy.

BACKGROUND: Medial opening wedge high tibial osteotomy (HTO) entails extensive soft tissue release that may lead to substantial perioperative bleeding. Although tranexamic acid (TXA) is a well-established blood-conserving agent in total joint arthroplasty, its potential to reduce blood loss in patients undergoing HTO has not been studied extensively. QUESTIONS/PURPOSES: (1) Does TXA reduce total estimated blood loss in HTO? (2) Does TXA use in HTO affect in-hospital endpoints as measured by visual analog scale (VAS) pain scores at rest the day after surgery, wound complications in the immediate postoperative period, blood transfusions, or symptomatic deep vein thrombosis? METHODS: Between January 2015 and May 2017, a single surgeon performed 156 HTOs, all of which were done using the medial opening wedge technique. We began using intravenous TXA for all HTOs in June 2016. This left us with 89 patients who were treated during a time when no TXA was used and 67 patients who were treated when all patients received TXA. Two patients in the control group had simultaneous TKA in the contralateral leg and one patient in each group had missing data so these patients were excluded, leaving 86 (97%) patients in the control group and 66 (98.5%) in the TXA group available for analysis in this retrospective study. There were no demographic differences between the groups in terms of age, sex, body mass index, and baseline hemoglobin values. Total estimated blood loss was the primary outcome variable, which was calculated using total blood volume and decrease in hemoglobin values. Secondary outcome variables included pain VAS at rest the day after surgery, wound complications in the immediate postoperative period, allogeneic blood transfusions, and occurrence of symptomatic thromboembolic manifestations. The decision on when to transfuse was based on predetermined criteria. An orthopaedic surgeon not involved in patient care collected the patient data from electronic medical records and did chart review. RESULTS: The TXA group had less total blood loss (372 ± 36 mL versus 635 ± 53 mL, mean difference 263 mL [95% confidence interval, 248-278]; p < 0.001). Between groups, differences in VAS pain scores at rest the day after surgery favored the TXA group but were small and unlikely to be clinically important. There were two wound complications in the control group (one hematoma and one superficial wound infection) and none in the TXA group. No patients in either group received a blood transfusion, and no symptomatic thromboembolic events were detected in either group. CONCLUSIONS: This study demonstrates that the systemic administration of TXA reduces postoperative blood loss in medial opening wedge HTO; however, insofar as no transfusions were administered to patients even before the routine use of TXA in this series, and no clinically important differences in pain scores were identified, the clinical benefit of routine use of TXA in patients undergoing HTO is uncertain. Our study was too small to make safety-related claims on rare endpoints such as wound complications or thromboembolic events. Larger, and preferably randomized, trials are needed to help define whether it is important to use TXA in this setting. Our data can help inform sample size calculations for such studies. LEVEL OF EVIDENCE: Level III, therapeutic study.

Extraspinal Percutaneous Osteoplasty for the Treatment of Painful Bony Metastasis.

BACKGROUND: Extraspinal percutaneous osteoplasties (POPs) are novel techniques for the treatment of painful bony metastasis, which is often the cause of both persistent and incidental breakthrough pain. This retrospective study explored the efficacy and complications of extraspinal POPs. METHODS: The origin of the cancer metastasis, performed POP sites, necessity of adjacent joint injections, pain and Karnofsky Performance Scale (KPS) scores, complications related to the POPs, and life expectancy were evaluated from the medical records from 2009 to 2016. RESULTS: A total of 47 (M/F = 28/19) patients had received 54 POPs, including costoplasty, scapuloplasty, ilioplasty, humeroplasty, ischioplasty, femoroplasty, sternoplasty, and puboplasty, in order of frequency. The most common sites for the origin of the cancer, in order of frequency, were the lung, liver, breast, colon, and kidney. All patients receiving POPs including scapuloplasty, ilioplasty, humeroplasty, and femoroplasty needed adjacent joint injections before or after the POPs. Pain due to metastatic lesions was reduced significantly immediately after the POPs and the reduction was sustained until the end of their lives. The median KPS was increased from 35.4% to 67.7% immediately after the POPs. There were no complications related to the procedures. The mean life expectancy after performing the POPs, for 35 patients which died afterwards, was 99.3 days, ranging from 1 to 767 days. CONCLUSION: Even though pain in the isolated POP sites may be difficult to measure due to overlapping systemic pain, the POPs provided immediate local pain relief, and the patients showed better physical performance without procedure-related complications.

Disposition of Remifentanil in Obesity: A New Pharmacokinetic Model Incorporating the Influence of Body Mass.

BACKGROUND: The influence of obesity on the pharmacokinetic (PK) behavior of remifentanil is incompletely understood. The aim of the current investigation was to develop a new population PK model for remifentanil that would adequately characterize the influence of body weight (among other covariates, e.g., age) on the disposition of remifentanil in the general adult population. We hypothesized that age and various indices of body mass would be important covariates in the new model. METHODS: Nine previously published data sets containing 4,455 blood concentration measurements from 229 subjects were merged. A new PK model was built using nonlinear mixed-effects modeling. Satisfactory model performance was assessed graphically and numerically; an internal, boot-strapping validation procedure was performed to determine the CIs of the model. RESULTS: Body weight, fat-free body mass, and age (but not body mass index) exhibited significant covariate effects on certain three-compartment model parameters. Visual and numerical assessments of model performance were satisfactory. The bootstrap procedure showed satisfactory CIs on all of the model parameters. CONCLUSIONS: A new model estimated from a large, diverse data set provides the PK foundation for remifentanil dosing calculations in adult obese and elderly patients. It is suitable for use in target-controlled infusion systems and pharmacologic simulation.

Advantages of Laparoscopic Radiofrequency Ablation Over Percutaneous Radiofrequency Ablation in Hepatocellular Carcinoma.

BACKGROUND: Inoperable hepatocellular carcinoma (HCC) can be treated with laparoscopic radiofrequency ablation (LRFA), which is generally a more accurate and accessible procedure than percutaneous RFA (PRFA). However, few studies have compared survival outcomes between LRFA and PRFA in patients with HCC. AIMS: This study aimed to compare the efficacy of LRFA and PRFA for HCC treatment. METHODS: Patients who underwent PRFA or LRFA as an initial treatment modality between April 2005 and April 2016 were enrolled in this study. The overall and recurrence-free survival rates were examined for each patient. Additionally, propensity score matching was performed for both groups. RESULTS: The baseline characteristics of patients in the PRFA and LRFA groups showed several minor differences. Multivariate analysis showed that the RFA method was not a critical determinant of recurrence-free or overall survival (p = 0.069 and p = 0.406). Among patients who underwent RFA as the initial treatment modality, there was no significant effect between either RFA procedures on survival. After propensity score matching, univariate analysis showed a significant difference in overall survival between PRFA and LRFA (p = 0.031). Multivariate analysis showed that LRFA is a strong factor that contributed to an improved overall survival in HCC patients (hazard ratio 0.108, p = 0.040). Furthermore, our data showed that LRFA was able to limit multiple intrahepatic recurrences, as well as prevent marginal recurrence. CONCLUSIONS: LRFA appears to be superior to PRFA in terms of survival. LRFA may help reduce mortality in HCC patients.