Bone cysts at the meniscal attachment are associated with a longer symptom duration among patients with arthroscopically treated medial meniscus posterior root tear.

PURPOSE: To elucidate the features of bone cysts at attachment sites of medial meniscus posterior root tears (MMPRTs). METHODS: Knees treated using arthroscopic surgery for MMPRT between 2015 and 2022 were retrospectively reviewed. Patients without a memory of onset (painful popping), prior knee surgeries, concomitant ligament or meniscus injuries or fractures were excluded. Duration from onset to magnetic resonance imaging (MRI) and type of tear were evaluated during arthroscopy. On radiography, meniscus signs (cleft/ghost/giraffe neck), bone cysts at the attachment site of the MMPRT and posterior shiny-corner lesions (PSCLs; bone marrow lesions on the meniscal-covered portion of the posterior tibial plateau) were evaluated. The sensitivity and specificity of the bone cysts were assessed by comparison with matched patients who underwent arthroscopic surgery for medial meniscus posterior horn tear. In addition, subgroups (cyst-positive/cyst-negative) among patients with MMPRT were created to assess the features of bone cysts. RESULTS: A total of 275 patients with MMPRT and 275 matched patients with posterior horn tears were evaluated. The sensitivity and specificity of bone cysts for MMPRT in this study were 22.2% and 98.6%, respectively. Among the 275 knees with MMPRT, compared with the cyst-negative group, the cyst-positive group had a longer duration from onset to MRI (12.9 ± 13.1 vs. 8.3 ± 10.9 weeks, respectively, p = 0.025) and reduced occurrence of PSCLs (18.0% vs. 42.0%, respectively, p = 0.031). CONCLUSION: The occurrence of bone cysts at the attachment site was helpful for the accurate diagnosis of MMPRT and related to longer duration from onset to MRI and reduced PSCLs. LEVEL OF EVIDENCE: Level III, cross-sectional study.

Erratum: Black Holes in an Effective Field Theory Extension of General Relativity [Phys. Rev. Lett. 121, 251105 (2018)].

This corrects the article DOI: 10.1103/PhysRevLett.121.251105.

Insufficient restoration of meniscal extrusion by transtibial pullout repair for medial meniscus posterior root tears.

PURPOSE: The long-term changes in the dynamics of the medial meniscus after transtibial pullout repair for medial meniscus posterior root tears (MMPRTs) are not completely understood. Thus, the aim of this study was to investigate the effects of transtibial pullout repair on MMPRTs and whether the effects would be sustained. METHODS: Nineteen knees with MMPRTs that were treated by trans-tibial pullout repair were enrolled in this study. Medial meniscus extrusion (MME) was measured by ultrasonography during knee extension (no weight-bearing with the knee at 0° extension: NW0°) and 90° flexion (no weight-bearing with the knee at 90° flexion: NW90°) with the patient in the supine position and with full weight-bearing (FW0°) preoperatively and at 3 and 12 months postoperatively. The clinical outcomes were assessed using the Knee Injury and Osteoarthritis Outcome Score, Lysholm score, and International Knee Documentation Committee score. RESULTS: The difference in MME with NW0° was not statistically significant between the preoperative (3.4 ± 1.0 mm) and 12-month postoperative (3.7 ± 0.6 mm) time points. The MME with NW90° at 3 (2.1 ± 0.7 mm) and 12 months (2.9 ± 0.6 mm) postoperatively were significantly lower than the preoperative values (3.4 ± 0.8 mm) (P < 0.05). However, the value significantly increased from 3 to 12 months postoperatively (P < 0.05). The MME with FW0° at 12 months postoperatively (4.3 ± 0.6 mm) was significantly larger than that at pre-operatively (3.6 ± 0.9 mm) (P < 0.05). All the patients' clinical conditions were significantly improved at 12 months postoperatively when compared to their preoperative clinical conditions. CONCLUSION: Surgery did not reduce the extrusion in the no weight-bearing and weight-bearing positions at knee extension, and these values increased in the postoperative period. In addition, while the surgery reduced the extrusion in the knee flexion position, the restoration achieved by the surgery was not sustained in the long term. LEVEL OF EVIDENCE: Level IV.

[A Case of Pathological Complete Response Induced by Preoperative Gemcitabine plus S-1 with Concurrent Radiation Therapy Followed by Gemcitabine plus S-1 Therapy in Borderline Resectable Pancreatic Cancer].

The patient was a 69-year-old man. He visited our hospital with a complaint of right back pain. An abdominal CT scan confirmed a hypovascular mass 35 mm in diameter in the pancreatic head. He was diagnosed with pancreatic head cancer (cT3, cN0, cM0, cStage ⅡA, borderline resectable-A). Gemcitabine plus S-1(GS)-based chemoradiation therapy(CRT) was performed, followed by 6 courses of GS therapy. Tumor markers were almost normalized, and subtotal stomach-preserving pancreaticoduodenectomy was performed. Histopathological examination of the resected specimen revealed highly atrophic pancreatic tissue with fibrosis and no evidence of residual cancer cells (pathological complete response). The patient remains disease-free 36 months after surgery. There are few reports of pancreatic cancer with pCR after GS-based chemoradiation therapy and subsequent GS therapy. We therefore report this case together with a review of the literature.

Preoperative prognostic nutritional index predicts postoperative infectious complications and oncological outcomes after hepatectomy in intrahepatic cholangiocarcinoma.

BACKGROUND: In the surgical treatment of intrahepatic cholangiocarcinoma (ICC), postoperative complications may be predictive of long-term survival. This study aimed to identify an immune-nutritional index (INI) that can be used for preoperative prediction of complications. PATIENTS AND METHODS: Multi-institutional data from 316 patients with ICC who had undergone surgical resection were retrospectively analysed, with a focus on various preoperative INIs. RESULTS: Severe complications (Clavien-Dindo grade III-V) were identified in 66 patients (20.8%), including Grade V complications in 7 patients (2.2%). Comparison of areas under the receiver operating characteristic curve (AUCs) among various INIs identified the prognostic nutritional index (PNI) as offering the highest predictive value for severe complications (AUC = 0.609, cut-off = 50, P = 0.008). Multivariate analysis revealed PNI <  50 (odds ratio [OR] = 2.22, P = 0.013), hilar lesion (OR = 2.46, P = 0.026), and long operation time (OR = 1.003, P = 0.029) as independent risk factors for severe complications. In comparing a high-PNI group (PNI ≥ 50, n = 142) and a low-PNI group (PNI <  50, n = 174), the low-PNI group showed higher rates of both major complications (27% vs. 13.4%; P = 0.003) and infectious complications (14.9% vs. 3.5%; P = 0.0021). Furthermore, median survival time and 1- and 5-year overall survival rates were 34.2 months and 77.4 and 33.8% in the low-PNI group, respectively, and 52.4 months and 89.3 and 47.5% in the high-PNI group, respectively (P = 0.0017). CONCLUSION: Preoperative PNI appears useful as an INI correlating with postoperative severe complications and as a prognostic indicator for ICC.

Prognostic Utility of the Glasgow Prognostic Score for the Long-Term Outcomes After Liver Resection for Intrahepatic Cholangiocarcinoma: A Multi-institutional Study.

OBJECTIVE: The usefulness of the modified Glasgow prognostic score (GPS) as a prognostic tool remains unclear for patients undergoing curative surgery for intrahepatic cholangiocarcinoma (ICC). Therefore, this study investigated the prognostic usefulness of the GPS for patients who underwent ICC surgery. METHOD: All ICC patients who had a curative-intent hepatectomy at 17 institutions between 2000 and 2016 were included. The correlation was assessed between the preoperative GPS and the baseline characteristics of the patients, histopathological parameters, surgical parameters, and the postresection overall survival (OS). RESULT: There were 273 patients who met the eligibility criteria between the years 2000 and 2016. The postoperative OS rates at 1, 3, and 5 years were 83.8%, 56.3%, and 41.5%, respectively (median OS, 47.7 months). A multivariate analysis revealed the factors that were associated with a worse OS, which included an increased GPS (hazard ratio = 1.62; 95% confidence interval [CI]: 1.01-2.53; P = 0.03), an elevated carcinoembryonic antigen level (hazard ratio = 1.60; 95% CI: 1.06-2.41; P = 0.02), an elevated carbohydrate antigen 19-9 level (hazard ratio = 1.55; 95% CI: 1.05-2.30; P = 0.03), undifferentiated carcinoma (hazard ratio = 2.41; 95% CI: 1.56-3.67; P < 0.01), and positive metastasis to the lymph nodes (hazard ratio = 2.54; 95% CI: 1.76-3.67; P < 0.01). In ICC patients after a hepatectomy, an elevated GPS was associated with poorer OS, even if the tumour factors that affected GPS were eliminated by propensity-score matching. CONCLUSION: Preoperative GPS can be useful to predict the postoperative outcomes of ICC patients. Therefore, this relatively simple and inexpensive scoring system can be utilized to further refine patient stratification as well as to predict survival.

Texture Analysis Using Preoperative Positron Emission Tomography Images May Predict the Prognosis of Patients With Resectable Oral Squamous Cell Carcinoma.

PURPOSE: Texture analysis is a computer-assisted technique used to measure intratumoral heterogeneity, which is known to have important roles in cancer research. This study aimed to assess the potential prognostic values of textural features extracted from preoperative 18F-fluorodeoxyglucose positron emission tomography images in patients with resectable oral squamous cell carcinoma. PATIENTS AND METHODS: This retrospective cohort study included patients with oral squamous cell carcinoma who underwent resection surgery. We extracted 31 textural indices from preoperative positron emission tomography images. Overall survival (OS) and disease-free survival (DFS) were chosen as the primary outcome variables, and the primary predictor variables were age, sex, primary tumor location, pathological T and N classification, histologic differentiation, resected margin, perineural and lymphovascular invasion, maximum standardized uptake value, and the 14 textural indices selected in the factor analysis. We analyzed OS and DFS using Kaplan-Meier curves, and the differences between survival curves were determined using a log-rank test. The independent prognostic factors were assessed using the Cox-proportional hazards model. RESULTS: We enrolled 81 patients (median age, 67.3 years; range, 32 to 88 years). The median follow-up duration was 50.1 months (range, 6.3 to 133.7 months). The univariable and multivariable analyses revealed that higher entropy values (≥1.91) were associated with worse OS (hazard ratio, 21.49; 95% confidence interval, 1.36 to 340.71; P = .03) and DFS (hazard ratio, 50.69; 95% confidence interval, 5.23 to 491.18; P = .001). CONCLUSIONS: This study showed that entropy is a statistically significant prognostic factor of both OS and DFS. Texture analysis using preoperative positron emission tomography images may contribute to risk stratification.

Sagittal Inclination Angle of Graft Is Associated With Knee Stability After Anatomic Anterior Cruciate Ligament Reconstruction.

PURPOSE: To evaluate whether the sagittal inclination angle (SIA) of a graft is associated with postoperative knee stability after anatomic anterior cruciate ligament (ACL) reconstruction. METHODS: All patients who had undergone anatomic ACL reconstruction between April 2014 and September 2015 in addition to volunteers with no history of knee injury were eligible for inclusion in this study. The patients were evaluated by magnetic resonance imaging of the knee in full extension at 1 year after surgery, as were volunteers. The posterior tibial slope (PTS) angle and the SIA of the intact ACL and reconstructed graft were measured relative to each medial and lateral tibial plateau. The patients were examined for knee stability by the side-to-side difference in the anterior tibial translation on stress radiographs at minimum 2-year follow-up. RESULTS: We included 43 patients (26 male, 17 female, mean age 32.8 ± 14.8 years) and 12 volunteers (7 male, 5 female, mean age 28.7 ± 3.1 years) as normal controls. The mean follow-up duration was 29.8 ± 3.6 months. The mean PTS angle and mean SIA in the patients did not significantly differ from those of the intact ACL. The PTS angle in the patients was not significantly correlated with postoperative side-to-side difference in the anterior tibial translation. However, the graft SIA was significantly correlated with the postoperative anterior tibial translation (medial SIA; r = 0.42, P = .005, lateral SIA; r = 0.52, P < .001). CONCLUSIONS: Even if anatomically reconstructed, the graft SIA in reference to the tibial plateau at full knee extension is variable and is associated with postoperative knee stability. The larger graft SIA was correlated with graft laxity after anatomic ACL reconstruction. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Patient-reported evaluation on giving way is important for return to preinjury activity level after Anterior Cruciate Ligament reconstruction.

PURPOSE: The present study evaluated the rate of returning to the preinjury level of competitive sports after ACLR and influential factors. METHODS: After excluding composite ligament injury cases, 96 patients with a Tegner activity score of ≥ 6 who were managed between April 2015 and March 2016 and had been followed for ≥ 2 years were included in the present study. The patients were evaluated for instability, and the following data were collected: second-look arthroscopy findings, muscle strength, and International Knee Documentation Committee (IKDC) subjective score (follow-up rate: 88.1%). RESULTS: The rate of returning to the preinjury level of competitive sports was 62/96 (64.6%). Only the total IKDC subjective score (odds ratio, 1.052; 95% confidence interval 1.004-1.102; p = 0.035) and the subjectively evaluated item about giving way (odds ratio, 1.762; 95% confidence interval 1.066-2.911; p = 0.027) were independently associated with the returning to the preinjury level of competitive sports after ACLR in the logistic regression analysis. CONCLUSION: The rate of returning to the preinjury level of competitive sports after ACLR was 64.6%, even if a good knee stability and healing status of the sutured meniscus were acquired after ACLR. The IKDC subjective score, especially the item about giving way, was significantly associated with the returning to the preinjury level of competitive sports. The factors assessed by patient-reported evaluations concerning giving way that may be related to functional performance, including brain activity, are important to consider to improve the rate of returning to the preinjury level of competitive sports. LEVEL OF EVIDENCE: III.

Internal bracing with an artificial ligament for superficial medial collateral ligament injury impairs the mechanical property of repaired native ligament: A porcine study.

BACKGROUND: Superficial medial collateral ligament (sMCL) injury is common, but there are no in vivo studies describing the biomechanical efficacy of anatomic repair with internal bracing for grade 3 injuries. METHODS: We used a porcine model to evaluate the efficacy of internal bracing using an artificial ligament for the early repair of acute, grade 3 sMCL injuries. Sixteen male castrated pigs were randomly assigned to a repair group: (1) anatomic repair using two suture anchors (Group R; n = 9) or (2) anatomic repair with internal bracing augmentation (Group IB; n = 7). The left knees were allocated to a sham surgery group (Group S; n = 16). All animals were sacrificed 4 weeks after surgery. The right and left femur-sMCL-tibia complexes were mounted on a tensile tester and stretched to failure using the same conditions as preconditioning at a cross-head speed of 50 mm/min. The internal bracing in Group IB was removed prior to the biomechanical testing. The failure mode and structural properties (upper yield load, maximum load, linear stiffness, and elongation at failure) were determined. RESULTS: Significant differences in failure mode were observed among the three groups. All sMCLs repaired with just the suture anchors (Group R) were avulsed from the femoral attachment, while most of the sMCLs repaired with internal bracing augmentation (Group IB) exhibited mid-substance tears (Group R vs Group IB, P = 0.0023). In Group S, 14 sMCLs were avulsed from the femoral attachment and two were avulsed from the tibial attachment (Group IB vs Group S, P < 0.001). No significant difference was observed between Group R and Group S. There were no significant differences in the upper yield load, maximum load, linear stiffness, or elongation at failure among the groups. CONCLUSIONS: Loading of an artificial ligament for internal bracing did not result in better structural properties of the repaired sMCL itself.

[A Case of a Huge, Mixed-Type IPMC with Suspected Rupture of the Omental Bursa That Was Effectively Treated with Gemcitabine plus Nab-Paclitaxel].

A 53-year-old woman was referred to our hospital because of upper abdominal pain and expansion of the pancreatic main duct. Enhanced computed tomography revealed expansion of the main pancreatic duct from the head to the tail; in addition, a 30 mm cystic tumor was observed in the pancreatic head and a 56 mm tumor was observed in the ventral side of the pancreatic body. Endoscopy revealed fistula formation in the duodenum of the Vater papilla on the oral side. The patient was diagnosed with an intraductal papillary mucinous carcinoma(IPMC). In addition, PET-CT revealed accumulation of FDG in the ventral side of the pancreatic body, and a disseminated nodule in the omental bursa was suspected. We administered 6 courses of gemcitabine plus nab-paclitaxel therapy, after which, the tumor in the ventral side of the pancreatic body disappeared. We then performed sub-stomach-preserving pancreatoduodenectomy. The results of abdominal cavity washing cytology were negative, and there were no disseminated nodules in the omental bursa. Therefore, we could perform R0 excision.

Aurora A regulates the architecture of the Golgi apparatus.

The Golgi apparatus plays roles in cell polarity, directional cell migration, and bipolar spindle assembly, as well as the secretary pathway. In addition, recent studies have suggested the Golgi-dependent control of mitotic entry. We studied the role of the centrosomal kinase Aurora A in maintaining the Golgi apparatus. Knockdown of Aurora A resulted in Golgi dispersal during interphase. Golgi dispersal was also induced by a selective Aurora A inhibitor, MLN8237. Conversely, overexpression of Aurora A led to tightly packed Golgi apparatus during interphase. Knockdown or inhibition of Aurora A had little or no effect on Golgi vesiculation during mitosis. By synchronizing cell division, we studied whether mitosis was required to induce Golgi dispersal during interphase. Aurora A inhibition induced aberrant mitotic spindle and Golgi dispersal only after mitosis. However, the cells treated with the inhibitor MLN8237 at earlier cell cycle stages (wherein the cells remained undivided) had a normal Golgi architecture. Knockdown or inhibition of Aurora A also led to aberrant integrity of centrosome and Golgi apparatus during interphase. These results suggest that Aurora A activity is involved in the maintenance of Golgi architecture and the relationship between the Golgi apparatus and centrosome.

Remarkable Short-Term Regression of a Posterior Mediastinum Metastasis From Primary Intraosseous Carcinoma Treated With Nivolumab: A Case Report.

Primary intraosseous carcinoma (PIOC; not otherwise specified) is a rare odontogenic malignancy that is believed to arise from the odontogenic epithelium. In addition, some cases arise in odontogenic cysts or other benign precursors. There are no established treatment protocols for PIOC because of its rarity. In particular, no standard therapy has been established for patients with recurrent or metastatic PIOC. This report describes a case in which the use of nivolumab showed a marked treatment response in metastatic PIOC. The patient was a 71-year-old man with PIOC. The patient underwent segmental mandibulectomy with modified radical neck dissection after neoadjuvant chemotherapy, including 2 cycles of paclitaxel, cetuximab, and carboplatin and 1 cycle of docetaxel, cisplatin, and 5-fluorouracil. The lesion rapidly enlarged during neoadjuvant chemotherapy, and surgical specimens showed no histologic therapeutic effects of chemotherapy. Three months after the surgery, contrast-enhanced computed tomograms showed posterior mediastinal lymph node metastasis. Treatment with nivolumab was initiated, and notable clinical improvement was noted after 2 cycles. Although it was a short-term treatment, remarkable effects were observed and no adverse events were noted during and after nivolumab treatment. Nivolumab could be an attractive treatment option for metastatic PIOC that is resistant to traditional chemotherapy and target therapy, including cetuximab. Further investigation of this treatment is warranted.

Identification of nuclear localization signals in the human homeoprotein MSX1.

MSX1 is one of the homeoproteins with the homeodomain (HD) sequence, which regulates proliferation and differentiation of mesenchymal cells. In this study, we investigated the nuclear localization signal (NLS) in the MSX1 HD by deletion and amino acid substitution analyses. The web-based tool NLStradamus predicted 2 putative basic motifs in the N- and C-termini of the MSX1 HD. Green fluorescent protein (GFP) chimera studies revealed that NLS1 (161RKHKTNRKPR170) and NLS2 (216NRRAKAKR223) were independently insufficient for robust nuclear localization. However, they can work cooperatively to promote nuclear localization of MSX1, as was shown by the 2 tandem NLS motifs partially restoring functional NLS, leading to a significant nuclear accumulation of the GFP chimera. These results demonstrate a unique NLS motif in MSX1, which consists of an essential single core motif in helix-I, with weak potency, and an auxiliary subdomain in helix-III, which alone does not have nuclear localization potency. Additionally, other peptide sequences, other than predicted 2 motifs in the spacer, may be necessary for complete nuclear localization in MSX1 HD.

Black Holes in an Effective Field Theory Extension of General Relativity.

Effective field theory methods suggest that some rather general extensions of general relativity include, or are mimicked by, certain higher-order curvature corrections, with coupling constants expected to be small but otherwise arbitrary. Thus, the tantalizing prospect to test the fundamental nature of gravity with gravitational-wave observations, in a systematic way, emerges naturally. Here, we build black hole solutions in such a framework and study their main properties. Once rotation is included, we find the first purely gravitational example of geometries without Z_{2} symmetry. Despite the higher-order operators of the theory, we show that linearized fluctuations of such geometries obey second-order differential equations. We find nonzero tidal Love numbers. We study and compute the quasinormal modes of such geometries. These results are of interest to gravitational-wave science but also potentially relevant for electromagnetic observations of the galactic center or x-ray binaries.

Idiopathic Isolated Unilateral Hypoglossal Nerve Palsy: A Report of 2 Cases and Review of the Literature.

Hypoglossal nerve palsy (HNP) is a common finding in neurologic diseases when associated with other cranial nerve palsies or further pathology and exhibits characteristic clinical manifestations, including unilateral atrophy of the musculature of the tongue. It occasionally appears as the initial or solitary sign of an intracranial or extracranial space-occupying lesion, head or neck injury, or vascular abnormality of the internal carotid artery. There are few cases of idiopathic isolated unilateral HNP, which should be diagnosed through exclusion. This report describes 2 patients who had different outcomes and presents a literature review of idiopathic isolated unilateral HNP. Case 1 was a 71-year-old man who was referred with a 1-month history of dysphagia and speech impairment. Intraoral examination disclosed marked left-side hemiatrophy of the tongue and deviation toward the left on protrusion. At coronal Tl-weighted magnetic resonance imaging, left-side hemiatrophy of the tongue was clearly visible through deviation of the median septum to the left. The patient was diagnosed with idiopathic isolated unilateral HNP through exclusion and was treated with steroids and mecobalamin, but he did not recover. Case 2 was a 32-year-old man complaining of tongue weakness for 2 days. On examination, left HNP was evident, with deviation of the tongue to the left on protrusion. He was diagnosed with idiopathic isolated unilateral HNP through exclusion and was treated with steroids. After 3 weeks, the patient had completely recovered. To the best of the authors' knowledge, this is the first detailed literature review on idiopathic isolated unilateral HNP. This condition is very rare but should be considered for diagnosis. It warrants a thorough and stepwise approach for etiologic diagnosis.

Patient age as a preoperative factor associated with tunnel enlargement following double-bundle anterior cruciate ligament reconstruction using hamstring tendon autografts.

PURPOSE: A few studies have detected associations of post-operative tunnel enlargement with sex, age, and the timing of anterior cruciate ligament reconstruction (ACLR). The aim of the present study was to investigate the correlation between post-operative tunnel enlargement following ACLR using hamstring tendon autografts and preoperative factors. The authors hypothesized that tunnel enlargement is associated with age in patients undergoing ACLR. METHODS: One hundred and six patients (male, n = 57; female, n = 49; mean age, 26.9 years) who underwent double-bundle ACL reconstruction were included in the present study. The time between injury and surgery was 26.3 ± 71.4 weeks. Computed tomographic scans of the operated knee were obtained at 2 weeks and 6 months after surgery. The area of the tunnel aperture was measured for the femoral anteromedial tunnel (FAMT), femoral posterolateral tunnel (FPLT), tibial anteromedial tunnel (TAMT), and tibial posterolateral tunnel. The percentage of tunnel area enlargement was defined as the area at 2 weeks after ACLR subtracted from the area at 6 months after ACLR and then divided by the area at 2 weeks after ACLR. Spearman's correlation coefficient was calculated for each factor. The patients were divided into two groups based on age. Patients aged <40 and ≥40 years were assigned to Groups A and B, respectively. The differences in the outcomes and characteristics of the two groups were evaluated. RESULTS: The percentage of enlargement of the FAMT, FPLT, and TAMT was correlated with patient age (r = 0.31, p = 0.001; r = 0.24, p = 0.012; and r = 0.30, p = 0.002, respectively). In total, 87 and 19 knees were classified into Groups A and B, respectively, based on patient age. The percentage of enlargement of the FAMT was significantly higher in Group B than A (78 vs. 60%, respectively; p = 0.01). The percentage of enlargement of the TAMT was significantly higher in Group B than A (53 vs. 36%, respectively; p = 0.03). CONCLUSION: The percentage of enlargement of the FAMT and TAMT was associated with patient age. These findings suggest the need to consider the possibility of tunnel enlargement when double-bundle ACLR is performed for patients aged >40 years. Age was a preoperative factor associated with tunnel enlargement. LEVEL OF EVIDENCE: III.

The remnant preservation technique reduces the amount of bone tunnel enlargement following anterior cruciate ligament reconstruction.

PURPOSE: The aim of the present study was to investigate the correlation between postoperative tunnel enlargement after ACLR and remnant tissue preservation using the hamstring tendon. METHODS: One hundred and ninety-two subjects (male, n = 101; female, n = 91; mean age 27.1) who had undergone double-bundle ACL reconstruction were included in the present study. The patients were divided into two groups: the remnant tissue preservation group (Group R) and the non-remnant tissue preservation group (Group N). Computed tomographic scans of the operated knee were obtained at 2 weeks and 6 months after surgery. The area of the tunnel aperture for the anteromedial femoral tunnel (FAMT), posterolateral femoral tunnel (FPLT), anteromedial tibial tunnel (TAMT), and posterolateral tibial tunnel (TPLT) was measured. The area at 2 weeks after ACLR was subtracted from the area at 6 months after ACLR and then divided by the area at 2 weeks after ACLR. The differences in the outcomes and characteristics of the two groups were evaluated. RESULTS: Seventy-seven knees were classified into Group R, and 115 knees were classified into Group N. The age, gender, and body mass index did not differ to a statistically significant extent. The percentages of FAMT and TAMT enlargement in Group R were significantly smaller in comparison with Group N (P = 0.003 and P = 0.03, respectively). The percentage of FPLT and TPLT enlargement in the two groups did not differ to a statistically significant extent. CONCLUSION: The remnant-preserving technique reduces the amount of bone tunnel enlargement. The present findings indicate the advantages of the remnant-preserving ACLR technique, and therefore the remnant-preserving technique should be recommended. LEVEL OF EVIDENCE: II.

Four-and-a-half LIM Domains 1 (FHL1) Protein Interacts with the Rho Guanine Nucleotide Exchange Factor PLEKHG2/FLJ00018 and Regulates Cell Morphogenesis.

PLEKHG2/FLJ00018 is a Gßγ-dependent guanine nucleotide exchange factor for the small GTPases Rac and Cdc42 and has been shown to mediate the signaling pathways leading to actin cytoskeleton reorganization. Here we showed that the zinc finger domain-containing protein four-and-a-half LIM domains 1 (FHL1) acts as a novel interaction partner of PLEKHG2 by the yeast two-hybrid system. Among the isoforms of FHL1 (i.e. FHL1A, FHL1B, and FHL1C), FHL1A and FHL1B interacted with PLEKHG2. We found that there was an FHL1-binding region at amino acids 58-150 of PLEKHG2. The overexpression of FHL1A but not FHL1B enhanced the PLEKHG2-induced serum response element-dependent gene transcription. The co-expression of FHL1A and Gßγ synergistically enhanced the PLEKHG2-induced serum response element-dependent gene transcription. Increased transcription activity was decreased by FHL1A knock-out with the CRISPR/Cas9 system. Compared with PLEKHG2-expressing cells, the number and length of finger-like protrusions were increased in PLEKHG2-, Gßγ-, and FHL1A-expressing cells. Our results provide evidence that FHL1A interacts with PLEKHG2 and regulates cell morphological change through the activity of PLEKHG2.

Cervical chyloma after neck dissection: a case report.

Cervical chylomas are rare pseudocystic collections that lack an epithelial lining and arise from the thoracic duct or its tributaries; although they typically develop after neck surgery or trauma, they can arise from unknown causes. Treatment options include not only conservative therapy, such as dietary modification, repeated aspirations, and sclerotherapy, but also include surgical excision. We describe a case of a chyloma in a 64-year-old Japanese woman with squamous cell carcinoma of the gingiva. The chyloma developed following left segmental mandibulectomy with radical neck dissection and reconstruction, using a titanium plate and a pectoralis major myocutaneous flap. One month after surgery, a left supraclavicular swelling was noted, so ultrasound-guided fine-needle aspiration and cytology were performed to exclude a recurrence of neck metastasis. The aspiration yielded a milky fluid without atypical or malignant cells on cytology, confirming the diagnosis of chyloma. Although we performed continuous compressive dressing and started the patient on a low-fat diet, the mass persisted. When the patient died of bone, lung, and liver metastases five months after the second surgery, the mass had not changed in size. Awareness of this complication is important to ensure timely diagnosis and appropriate treatment.