Preoperative radiographic parameters in the case of using a narrow-version femoral implant in total knee arthroplasty.

BACKGROUND: Recently, total knee arthroplasty (TKA) designs that allow the use of narrow-version femoral implants have been introduced to avoid femoral overhang. The purpose of this study was to investigate the frequency of the use of narrow-version femoral implants and identify the difference in radiographic parameters between using a narrow-version femoral implant and a standard-version femoral implant in TKA. METHODS: A retrospective study was conducted on 504 primary TKAs using a TKA system (Anthem or Persona) that allowed narrow-version femoral implants. Anteroposterior (AP) dimension, mediolateral (ML) dimension, and modified aspect percentage ratio (ML/AP dimension) of the distal femur in preoperative radiographs were compared between a standard-version group (n = 275) and a narrow-version group (n = 229). A cut-off value of a modified aspect percentage ratio indicating the need for a narrow-version femoral implant was determined using the receiver operating characteristic (ROC) curve. RESULTS: Mean ML dimension was 80.9 ± 6.1 mm in the standard-version group and 77.3 ± 4.4 mm in the narrow-version group (p < 0.001). Mean modified aspect percentage ratio was 138.8 ± 8.1% in the standard-version group and 131.7 ± 6.3% in the narrow-version group (p < 0.001). The optimum cut-off point of the modified aspect percentage ratio for narrow-version femoral implants was 135.4% (sensitivity: 72.0%; specificity: 66.7%) for Anthem and 133.3% (sensitivity: 75.9%, specificity: 76.4%) for Persona. CONCLUSION: In the narrow-version femoral implant group, the ML dimension and the mean modified aspect percentage ratio were smaller than in the standard-version femoral implant group. A smaller modified aspect percentage ratio of the distal femur in preoperative radiographs could predict the need for narrow-version femoral implants in TKA. It was suggested that the cut-off point could be suggested as 135.4% for Anthem TKA design and 133.3% for Persona TKA design. These radiographic parameters are cost-effective and easily applicable for planning a TKA.A smaller modified aspect percentage ratio of the distal femur in preoperative radiographs could predict the need for narrow-version femoral implants in TKA. The cut-off point was 135.4% for Anthem TKA design and 133.3% for Persona TKA design.

One-Step Polymerase Chain Reaction-Free Nanowire-Based Plasma Cell-Free DNA Assay to Detect EML4-ALK Fusion and to Monitor Resistance in Lung Cancer.

BACKGROUND: Next-generation sequencing has mostly been used for genotyping cell-free DNA (cfDNA) in plasma. However, this assay has several clinical limitations. We evaluated the clinical utility of a novel polymerase chain reaction-free nanowire (NW)-based plasma cfDNA assay for detecting ALK fusion and mutations. PATIENTS, MATERIALS, AND METHODS: We consecutively enrolled 99 patients with advanced non-small cell lung cancer undergoing a fluorescence in situ hybridization (FISH) test for ALK fusion; ALK-positive (n = 36). The NW-based assay was performed using 50-100 µL of plasma collected at pretreatment and every 8 weeks during ALK inhibitor treatment. RESULTS: There was high concordance between the NW-based assay and the FISH test for identification of ALK fusion (94.9% with a kappa coefficient value of 0.892, 95% confidence interval [CI], 0.799-0.984). There was no difference in the response rate to the first anaplastic lymphoma kinase inhibitor between the ALK-positive patients identified by the NW-based assay and by the FISH test (73.5% vs. 72.2%, p = .931). In the ALK variant analysis, variants 1 and 3 subgroups were detected in 27 (75.0%) and 8 (22.2%) patients, respectively. Among 24 patients treated with crizotinib, variant 3 subgroup was associated with worse median overall survival than variant 1 subgroup (36.5 months; 95% CI, 0.09-87.6 vs. 19.8 months; 95% CI, 9.9-not reached, p = .004]. A serial assessment identified that ALK L1196M resistance mutation emerged before radiologic progression during crizotinib treatment. CONCLUSION: The newly developed simple NW-based cfDNA assay may be clinically applicable for rapid diagnosis of ALK fusion with its variant forms and early detection of resistance. IMPLICATIONS FOR PRACTICE: The authors developed a novel one-step polymerase chain reaction-free nanowire (NW)-based plasma cell-free DNA (cfDNA) assay. This study evaluated the clinical utility of this novel method for the diagnosis of EML4-ALK fusion in advanced non-small cell lung cancer (NSCLC). The NW-based assay and FISH test showed high concordance rate in 99 patients with advanced NSCLC. Serial cfDNA assessment demonstrated this method provided early detection of resistance before radiologic progression during crizotinib treatment. Taken together, plasma cfDNA genotyping by the NW-based cfDNA assay may be useful for the rapid diagnosis of ALK fusion, classifying variants, and early detection of resistance.

Temporary 12-Hour Drain Clamping versus 3-Hour Drain Clamping in Simultaneous Bilateral Total Knee Arthroplasty.

Background: Total knee arthroplasty (TKA) is a procedure that has a risk of perioperative blood loss and allogeneic blood transfusion. The purpose of the present study was to compare the perioperative blood loss and transfusion rate between the 3-hour interval clamping and 12-hour interval clamping of closed suction drainage after simultaneous bilateral total knee arthroplasty (SBTKA). Methods: A total of 122 SBTKAs were enrolled in this retrospective study. A 3-hour clamping protocol was applied in 53 SBTKAs and a 12-hour clamping protocol was applied in 69 SBTKAs. The amount of perioperative blood loss, transfusion requirements, postoperative hemoglobin and hematocrit levels, the lowest hemoglobin and hematocrit levels during hospitalization, readmission within 90 days, and clinical outcomes were compared between the 3-hour clamping group and the 12-hour clamping group. Results: The 12-hour clamping group had fewer patients requiring transfusion (26.1%, 18/69) than did the 3-hour clamping protocol group (49.1%, 26/53) (p = 0.008). The 12-hour clamping group had a lower amount of estimated blood loss (1,426.9 ± 421.5 mL) than did the 3-hour clamping protocol group (1,882.1 ± 445.6 mL) (p < 0.001). The 12-hour clamping group showed higher hemoglobin and hematocrit levels (both p < 0.001) on postoperative day 5 than did the 3-hour clamping group. The lowest hemoglobin and hematocrit levels were higher in the 12-hour clamping group than in the 3-hour clamping group (p = 0.039 and p = 0.016, respectively). Within 1 postoperative month, there were 2 cases of wound dehiscence in each group (p = 0.585). But, at 1 year after the operation, no serious complications occurred in the two groups. Conclusions: Compared to the 3-hour clamping protocol, the 12-hour clamping protocol significantly reduced transfusion requirements, estimated blood loss volume, and hemoglobin and hematocrit levels after SBTKA. We suggest that 12-hour temporary clamping should be considered for reducing transfusion rates.

Comparison between selective caudal fixed screw construct and all variable screw construct in anterior cervical discectomy and fusion.

This retrospective comparative study aimed to compare the efficacy of selective caudal fixed screw constructs with all variable screw constructs in anterior cervical discectomy and fusion (ACDF). Thirty-five patients who underwent surgery using selective caudal fixed screw construct (SF group) were compared with 44 patients who underwent surgery using all variable constructs (AV group). The fusion rate, subsidence, adjacent level ossification development (ALOD), adjacent segmental disease (ASD), and plate-adjacent disc space distance were assessed. The one-year fusion rates assessed by computed tomography bone bridging and interspinous motion as well as the significant subsidence rate did not differ significantly between the AV and SF groups. The ALOD and ASD rates and plate-adjacent disc space distances did not significantly differ between the two groups at both the cranial and caudal adjacent levels. The number of operated levels was significantly associated with pseudarthrosis in the logistic regression analysis. The stability provided by the locking mechanism of the fixed screw did not lead to an increased fusion rate at the caudal level. Therefore, the screw type should be selected based on individual patient's anatomy and surgeon's experience without concern for increased complications caused by screw type.