ARGONAUTE1-binding Tudor domain proteins function in small interfering RNA production for RNA-directed DNA methylation.

Transposable elements (TEs) contribute to plant evolution, development, and adaptation to environmental changes, but the regulatory mechanisms are largely unknown. RNA-directed DNA methylation (RdDM) is 1 TE regulatory mechanism in plants. Here, we identified that novel ARGONAUTE 1 (AGO1)-binding Tudor domain proteins Precocious dissociation of sisters C/E (PDS5C/E) are involved in 24-nt siRNA production to establish RdDM on TEs in Arabidopsis thaliana. PDS5 family proteins are subunits of the eukaryote-conserved cohesin complex. However, the double mutant lacking angiosperm-specific subfamily PDS5C and PDS5E (pds5c/e) exhibited different developmental phenotypes and transcriptome compared with those of the double mutant lacking eukaryote-conserved subfamily PDS5A and PDS5B (pds5a/b), suggesting that the angiosperm-specific PDS5C/E subfamily has a unique function in angiosperm plants. Proteome and imaging analyses revealed that PDS5C/E interact with AGO1. The pds5c/e double mutant had defects in 24-nt siRNA accumulation and CHH DNA methylation on TEs. In addition, some lncRNAs that accumulated in the pds5c/e mutant were targeted by AGO1-loading 21-nt miRNAs and 21-nt siRNAs. These results indicate that PDS5C/E and AGO1 participate in 24-nt siRNA production for RdDM in the cytoplasm. These findings indicate that angiosperm plants evolved a new regulator, the PDS5C/E subfamily, to control the increase in TEs during angiosperm evolution.

Patients with keratinization disorders due to ABCA12 variants showing pityriasis rubra pilaris phenotypes.

Pathogenic variants in ABCA12 are important causative genetic defects for autosomal recessive congenital ichthyoses (ARCI), which include congenital ichthyosiform erythroderma (CIE), harlequin ichthyosis, and lamellar ichthyosis. In addition, pathogenic variants in ABCA12 are known to cause a localized nevoid form of CIE due to recessive mosaicism. We previously reported siblings who carried an ABCA12 variant but did not show a "congenital" phenotype. They were considered to have pityriasis rubra pilaris (PRP). Here, we present a further patient with ABCA12 variants whose phenotype was not congenital ichthyosis, in an independent family. Notably, these three patients had geographic unaffected areas. Such areas are not usually found in patients with ARCI who have ABCA12 variants, suggesting mild phenotypes for these patients. Interestingly, the histological features of the ichthyotic lesions in these patients resembled those of PRP. All three patients had homozygous pathogenic missense variants in ABCA12. Our findings expand the phenotypic spectrum of patients with ABCA12 variants.

Gluteal Compartment Syndrome After Femoral Nail Extraction: A Case Report.

Gluteal compartment syndrome is a rare disorder and no definitive treatment has yet been established. Fasciotomy is often the treatment of choice for gluteal compartment syndrome, but there have been only a few cases that have improved with conservative therapy. A 26-year-old male with a body mass index of 40.5 who underwent femoral nail extraction surgery had severe pain in the right buttock and numbness in the right lower extremity. Initially, we suspected transient pain due to prolonged exposure to the same posture, but muscle weakness in the lower extremities and worsening of renal function appeared over time. Orthopedic evaluation revealed physical examination findings and MRI imaging findings consistent with gluteal compartment syndrome. Conservative treatment with temporary dialysis was chosen instead of fasciotomy because of the time required for diagnosis. Dialysis was started on postoperative day 3, renal function and muscle weakness recovered over time, and the patient was discharged home on postoperative day 37. At six months post-op, the patient was walking without pain and he had no changes in his peripheral neurologic examination compared to his preoperative baseline. Orthopedic surgeons should always be aware of the possibility of gluteal compartment syndrome when especially obese patients with prolonged operation times appeal to acute buttock pain. Diagnosis should be made as early as possible to get a good prognosis.

Bisphosphonates Prescription for Patients With Hip Fractures Based on Evaluation by a Dentist.

Background The purpose of this study is to clarify the current status of the prescription of postoperative bisphosphonates for patients with hip fractures and to explore the factors that prevent the postoperative prescription of bisphosphonates. Methods Of 180 patients with hip fractures treated surgically at our hospital between August 2019 and April 2020, 149 patients (46 men and 103 women; mean age: 83.9 ± 9.0 years), excluding 31 patients already prescribed bisphosphonates or denosumab, were included in the study. All patients were treated based on our clinical pathway, and their risk of jaw osteonecrosis was evaluated prior to the initiation of bisphosphonates by a dentist in our hospital. We collected data from the medical records on osteoporosis treatment interventions at admission and discharge, the reasons why postoperative bisphosphonates could not be prescribed at discharge, the proportion of patients who had follow-ups at our hospital, and patients' osteoporosis treatment status. Results Eighteen (12.8%) and 95 (63.8%) patients were prescribed anti-osteoporosis drugs at admission and discharge, respectively. One hundred and twenty-one patients (86.8%) could not be prescribed postoperative bisphosphonates at discharge - 71 (58.7%) because of oral hygiene problems, 34 (28.1%) because they did not have regular dental consultations, seven (5.8%) because of renal dysfunction, eight (6.6%) because of poor cognitive and swallowing function, and one (0.8%) because of medication side effects. Forty-nine patients (32.9%) went to our hospital for follow-up and 11 were introduced to bisphosphonates or denosumab at follow-up. Conclusions The number of patients with hip fractures who were prescribed postoperative bisphosphonates was low in our study. The oral hygiene problems identified by dentists accounted for responsible for the low prescription rate of postoperative bisphosphonates. Therefore, coordination with dentists may be important to increase the postoperative bisphosphonate prescription.

Co-existence of Lumbar Disc Herniation and Posterior Ring Apophyseal Fracture: It Is Not Rare and Computed Tomography Is Useful.

Introduction Posterior ring apophyseal fracture (PRAF) is characterized by the separation of bone fragments and sometimes coexists with lumbar disc herniation (LDH). However, how often these conditions coexist and the details of the clinical course remain unclear. Methods We analyzed 200 patients who underwent surgical treatment for LDH at our hospital from January 2016 to December 2020. Among these, we reviewed 21 patients who underwent microendoscopic surgery to treat PRAF. They consisted of 11 male and 10 female patients, ranging in age from 15 to 63 years. The average age was 32.8 months, and the average follow-up period was 39.8 years. We performed simple roentgenography and magnetic resonance imaging for all patients and computed tomography for about 80% of the patients. We evaluated the type of PRAF fragment (Takata classification), disease level, Japanese Orthopedic Association (JOA) score, Roland-Morris Disability Questionnaire (RDQ) score, operating time, intraoperative blood loss, and perioperative complications. Results A total of 10.5% of patients with LDH also had PRAF. The mean JOA score significantly improved from 10.6 ± 5.7 points before surgery to 21.4 ± 5.1 points at the final observation (p < 0.05). The mean RDQ score significantly improved from 17.1 ± 4.5 preoperatively to 5.5 ± 0.5 at the final observation (p < 0.05). The average operation time was 88.6 minutes. There were no complications requiring early surgery that were due to postoperative infection or epidural hematoma, but one patient required reoperation. Conclusion This study showed that PRAF coexisted with LDH in about 10% of cases, and the outcomes of surgical treatment were generally good. Computed tomography is recommended to improve the diagnostic rate and assist with surgical planning and intraoperative decision-making.

Efficacy of Corticosteroid Addition to a Periarticular Cocktail Injection to Counteract Nausea and Vomiting After Total Knee Arthroplasty.

BACKGROUND: Intraoperative periarticular injection of a "cocktail" of drugs is undertaken commonly in total knee arthroplasty (TKA). The addition of a corticosteroid to the periarticular injection is believed to offer greater pain relief because of its local anti-inflammatory effects, but the prevalence of postoperative nausea and vomiting (PONV) is not known. This retrospective observational study aimed to elucidate the relationship between corticosteroid addition to a periarticular cocktail injection (PCI) and PONV. MATERIALS AND METHODS: Fifty-nine patients who underwent unilateral TKA for primary osteoarthritis were divided into two groups: corticosteroid and non-corticosteroid. The former had triamcinolone acetonide (40 mg) added to the same PCI. The primary outcome was the prevalence of nausea and vomiting within 48 hours following TKA. RESULTS: There was no significant difference between the two groups in terms of patient demographics. The overall prevalence of PONV was 16.9%. Fewer patients in the corticosteroid group complained of PONV than in the non-corticosteroid group (6.4% vs. 58.3%; p = 0.012). CONCLUSIONS: The addition of a corticosteroid to a PCI suppressed PONV. Our results suggested that cocktail injections may have local and systemic effects.

Anti-desmoglein 1 antibody-positive mother and antibody-negative child with Darier's disease.

We report a mother and an adult son with Darier's disease. The mother, 76 years old and Japanese, had positivity for anti-desmoglein (Dsg)1 antibodies. She had erythema with hyperkeratosis and seborrheic and interstitial blistering. A high level of anti-Dsg1 antibodies was detected in the serum. Histopathological examination showed acantholysis and direct immunofluorescence testing revealed intercellular IgG and C3 deposition of the epidermis. Although she was diagnosed as having pemphigus foliaceus, the skin lesions slightly improved with immunosuppressive therapy. Her son, 47 years old, had similar skin lesions on the seborrheic and interstitial parts, but the anti-Dsg1 antibodies were negative in his serum. Histopathological examination showed acantholysis and dyskeratotic cells. Although Hailey-Hailey disease was first suspected, no mutation in the ATP2C1 was detected in either patient. Trio-exome analysis including the father showed a heterozygous c.2027C>A transition on exon 14 of ATP2A2, causing a replacement at amino acid 676 (p.Ala676Asp) in the mother and son only. The two patients were then diagnosed as having Darier's disease. Exome analysis further showed that a novel heterozygous missense mutation of DSG1 was identified only in the affected mother. Anti-Dsg1 antibody-positive Darier's disease is reported here for the first time. Very rare coexistence of Darier's disease and anti-Dsg1 antibody-positivity might be associated with this novel heterozygous DSG1 mutation. Experimental evidence is required to validate this hypothesis.

Fission yeast Dis1 is an unconventional TOG/XMAP215 that induces microtubule catastrophe to drive chromosome pulling.

The shortening of microtubules attached to kinetochores is the driving force of chromosome movement during cell division. Specific kinesins are believed to shorten microtubules but are dispensable for viability in yeast, implying the existence of additional factors responsible for microtubule shortening. Here, we demonstrate that Dis1, a TOG/XMAP215 ortholog in fission yeast, promotes microtubule shortening to carry chromosomes. Although TOG/XMAP215 orthologs are generally accepted as microtubule polymerases, Dis1 promoted microtubule catastrophe in vitro and in vivo. Notably, microtubule catastrophe was promoted when the tip was attached to kinetochores, as they steadily anchored Dis1 at the kinetochore-microtubule interface. Engineered Dis1 oligomers artificially tethered at a chromosome arm region induced the shortening of microtubules in contact, frequently pulling the chromosome arm towards spindle poles. This effect was not brought by oligomerised Alp14. Thus, unlike Alp14 and other TOG/XMAP215 orthologs, Dis1 plays an unconventional role in promoting microtubule catastrophe, thereby driving chromosome movement.

Prophylactic Intrawound Vancomycin Powder in Minimally Invasive Spine Stabilization May Cause an Acute Inflammatory Response.

Introduction Surgical site infections (SSIs) with methicillin-resistant Staphylococcus aureus are serious complications of spinal instrumentation surgery. Many spine surgeons are concerned that using prophylactic vancomycin powder will lead to certain risks: the development of multidrug-resistant pathogens, anaphylactic reactions, and organ toxicity. Minimally invasive spine stabilization (MISt) is associated with shorter operation times and less blood loss and may therefore require the use of less vancomycin powder, which may reduce these risks. This retrospective comparative study of patients who underwent MISt at a single institution aimed to evaluate the complications (such as allergy, SSIs, and organ toxicity) and the local and serum levels associated with using prophylactic intrawound vancomycin powder compared with IV cefazolin alone. Methods Thirty-four patients received intrawound vancomycin powder (1 g) applied during wound closure in minimally invasive posterior lumbar interbody fusion (MIS-PLIF). This group was compared with 133 control patients who did not receive vancomycin. White blood cell counts and C-reactive protein (CRP) levels were measured for both groups on postoperative days (PODs) 1, 3, and 7 and were statistically analyzed. In the vancomycin group, serum vancomycin levels were measured on PODs 1, 3, 7, and 14; drain vancomycin levels and postoperative blood loss were determined on PODs 1 and 2. Results The CRP levels on PODs 1 and 3 were significantly higher in the vancomycin group than in the control group (P<0.001, P=0.024). In the vancomycin group, mean drain levels trended downward from 313 µg/mL (POD 1) to 155 µg/mL (POD 2). These levels correlated negatively with drain drainage volume on both days (POD 1: r=-0.48, P=0.015; POD 2: r=-0.47, P=0.019). Mean serum vancomycin levels also trended downward from 2.3 µg/mL (POD 1) to 1.7 µg/mL (POD 14). Conclusions Our results unexpectedly demonstrated that the local application of vancomycin powder causes an acute inflammatory response and the long-term detection of low serum vancomycin levels. Less than 1 g of intrawound vancomycin powder may be useful only at high risk of SSI.

Factors Affecting Postoperative Spinal Epidural Hematoma and the Optimal Order of Vertebral Body Decompression in Multivertebral Microendoscopic Laminectomy.

Purpose Symptomatic postoperative spinal epidural hematoma (POSEH) is a complication of spine surgery that occurs infrequently but may cause ongoing serious neurological damage. Due to the narrow entry portal, the risk of hematoma is increased after microendoscopic laminectomy (MEL) compared with conventional open surgery, and the risk might be even higher for multivertebral MEL (m-MEL). The purpose of this study was to clarify the factors affecting the development of POSEH after m-MEL and identify the optimal order for the decompression of vertebral bodies. Methods A total of 313 patients who underwent m-MEL from 2016 to 2020 were retrospectively assessed. The cohort comprised 238 patients who underwent two-level MEL, 67 who underwent three-level MEL, and eight who underwent four-level MEL. Symptomatic POSEH was defined as the presence of an epidural hematoma at the surgical site on MRI with symptoms such as lower extremity pain or muscle weakness. We elucidated the incidence of POSEH at each vertebral level and investigated the relationship between POSEH and possible risk factors such as clinical and operative variables. Results There were 41 patients in the POSEH group and 272 patients in the non-POSEH group. Seven patients in the POSEH group underwent reoperation. The occurrence of POSEH was related to the number of decompressed vertebral bodies. Patients who underwent L2/3 and L3/4 decompression at the end of the procedure also showed a higher incidence of POSEH at the surgical level. Conclusion In patients undergoing m-MEL, treatment of the upper lumbar vertebrae at the end of decompression surgery might be a risk factor for symptomatic POSEH. The incidence of POSEH was particularly increased at L2/3, suggesting that L2/3 decompression should not be performed at last and that careful hemostasis should be applied.

Efficacy of Nerve Root Block for the Treatment of Lumbar Spinal Canal Stenosis in Adults Older Than 80 Years of Age.

BACKGROUND: Patients with advanced lumbar spinal canal stenosis (LCS) often prefer non-operative treatment owing to decreased physiological function and comorbidities. Although the therapeutic value of selective nerve root block (SNRB) for LCS is confirmed, there are few reports of its effectiveness in the elderly. We investigated the efficacy of SNRB for LCS in patients over 80 years of age. METHODS:  The subjects were 112 patients aged over 80 years (mean age: 84 years; 45 men and 67 women ) with medication-resistant LCS without cauda equina syndrome who underwent SNRB. Cases with acute-onset lumbar disc herniation were excluded. We retrospectively investigated and compared the presence or absence of surgery, effect of SNRB, number of procedures, duration of disease, and magnetic resonance imaging findings. Patients who could avoid the surgery by SNRB were defined as the effective group. Patients whose symptoms were not relieved by SNRB and who underwent surgery and those whose symptoms were not relieved but who continued conservative treatment were defined as the ineffective group. A total of one to seven SNRBs were performed in both groups, and the same spine surgeon performed the entire procedure from SNRB to surgery. RESULTS:  There were 86 nonoperative patients (69 effective cases) and 26 operative patients; the overall rate of effectiveness was 61% (69/112 patients). The area of the spinal canal at the responsible level was 108.63 mm2 in the effective group compared with 77.06 mm2 in the ineffective group. This was significantly narrower in the ineffective group (p=0.0094). There was no significant difference in the duration of illness, number of blocks, or hernia complication rate between the groups. No patient experienced severe neuralgia that may have been caused by neuropathy during SNRB. DISCUSSION: Our outcome showed that more than 60% of older patients with LCS showed symptomatic improvement with SNRB. SNRB can be performed relatively safely in the elderly and appears to be a favorable treatment option for older patients with various risks, such as poor general condition. CONCLUSIONS: Multiple sessions of SNRB may provide older patients with symptomatic improvement and may be an option for treatment.

Dermoscopic furrow ink test of the palmar lesion in loricrin keratoderma.

Palmoplantar keratodermas (PPK) comprise a heterogeneous group of keratinization disorders that gradually progress during childhood, resulting in difficulties to establish a diagnosis and to identify a candidate gene for sequencing. Dermoscopic examination with staining of palmoplantar skin using a whiteboard marker, so-called "furrow ink test", could be a useful tool for differentiation between furrow and ridge in understanding the morphological characteristics of PPK. One of the striking features in autosomal dominant loricrin keratoderma (LK) is diffuse PPK with honeycomb pattern. In this study, we performed dermoscopic furrow ink test in a Japanese family of LK with the most frequent mutation c.684dup, p.Ser229Valfs*107 in the loricrin gene. The severe lesion revealed that irregular circular hyperkeratoses were aggregated and normal structures of furrows and ridges were disrupted. To accurately describe the nature of this dermoscopic patterned skin surface, we suggest that the condition could be termed as "irregular cobblestone appearance" rather than "honeycomb pattern". Regular cobblestone appearance to maintain parallel furrow structure was observed in early or mild hyperkeratotic lesions. Eccrine sweat glands that open on the surface of ridges nearly disappeared, resulting in hypohidrosis.

Comparison of Microendoscopic Laminotomy (MEL) Versus Spinous Process-Splitting Laminotomy (SPSL) for Multi Segmental Lumbar Spinal Stenosis.

Aims  This study was aimed to compare the perioperative and postoperative outcomes of patients who underwent posterior decompression for multi-segmental lumbar spinal stenosis by microendoscopic laminotomy (MEL) versus spinous process-splitting laminotomy (SPSL) retrospectively. Methods We retrospectively reviewed 73 consecutive patients who underwent two or three levels MEL (n=51) or SPSL (n=22) for lumbar spinal stenosis between 2012 and 2018. The perioperative outcomes were operative time, intraoperative blood loss, length of postoperative hospital stay, complications, and reoperation rate. The postoperative outcomes were evaluated using a visual analog scale (VAS) and the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) scores at one year postoperatively. Results The mean follow-up time was 26.6 months in MEL and 35.6 months in SPSL. The mean operative time was significantly longer in MEL than SPSL (two levels, 183.6 ± 43.2 versus 134.8 ± 26.7 min, respectively; three levels: 241.6 ± 47.8 versus 179.9 ± 28.8 min, respectively). MEL's mean postoperative hospital stay was significantly shorter than SPSL (12.3 ± 5.9 versus 15.5 ± 7.2 days, respectively). There was no significant difference in the mean intraoperative blood loss, complication rate, reoperation rate, and postoperative outcomes between the two groups. Conclusions This study suggests that both techniques are effective in treating multi-segmental lumbar spinal stenosis. There was no significant difference between the two procedures in intraoperative blood loss (IBL), complications rate, reoperation rate, or improvement in VAS and Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) scores. MEL had an advantage in the postoperative hospital stay.

Risk Factors for Incidence of Postoperative Spinal Epidural Hematoma Following Multilevel Microendoscopic Laminectomy.

INTRODUCTION: Due to the narrow portal of entry, microendoscopic laminectomy (MEL) is associated with a risk of postoperative spinal epidural hematoma (POSEH). This risk might be higher when performing multiple-level (m-) MEL. The purpose of this study is to clarify the incidence rate of POSEH following single-level (s-) and m-MEL by each interlaminar level and identify the risk factors for POSEH following m-MEL. METHODS: A total of 379 patients underwent MEL of the lumbar spine (s-MEL, n=141; m-MEL, n=238). We determined the incidence of POSEH following s-MEL and m-MEL by each interlaminar level. For m-MEL, we clarified the correlation between POSEH and possible risk factors, such as operative findings, the sequence of operated interlaminar levels, and the preoperative cross-sectional dural area (CSA) on magnetic resonance imaging. RESULTS: The incidence rate at L2/3 was significantly higher than that at L3/4 and L4/5. Patients who underwent L2/3 decompression at the end of the procedure showed a higher incidence of POSEH at the L2/3 level. Preoperative spinal stenosis was associated with POSEH at the L2/3 level, and CSA of 56 mm2 was a predictive factor for POSEH. Logistic regression analysis revealed that both were significant risk factors. CONCLUSIONS: In patients undergoing m-MEL, the incidence of POSEH is highest at the L2/3 level, and treatment of the L2/3 level at the end of the procedure and the presence of spinal stenosis are risk factors for POSEH.

Massive Lumbar Disc Herniation Causing Cauda Equina Syndrome That Presents As Bladder and Bowel Dysfunction in the Absence of Lower Extremity Weakness.

The purpose of this report is to examine the features of cauda equina syndrome (CES) presenting as bladder and bowel dysfunction in the absence of lower extremity weakness. Between July 2015 and July 2016, we experienced four cases of massive LDH causing CES that presented as bladder and bowel dysfunction in the absence of lower extremity weakness. Herein, we describe the clinical features of these four patients (two males and two females) who were followed for a minimum of two years postoperatively. The mean age at the time of surgery was 46.8 years (range, 37-71 years). The disc herniation lesion was at the L4/5 level in one patient, and the L5/S1 level in three. The mean interval between the onset of CES and complete surgical decompression was 10.5 days (range, 1-18 days). Postoperative outcomes were better than poor in three of four cases, while one case had residual sphincter dysfunction. LDH causing CES is considered an indication for immediate surgical decompression; however, diagnosis of CES is likely to be delayed in atypical cases of CES that present as bladder and bowel dysfunction in the absence of lower extremity weakness. Diagnosis of CES tended to be delayed in cases without lower extremity weakness. Clinicians should recognize even sensory impairment alone of the dominant area supplied by S2-4 is an important diagnostic sign of CES in the early stage.

Association of Postoperative Neutrophil Lymphocyte Ratio (NLR) and Monocyte Lymphocyte Ratio (MLR) with the Presence of Osteoporosis in Japanese Patients after Hip Fracture Surgery: A Retrospective Cohort Study.

BACKGROUND: The diagnosis of osteoporosis is based on bone mineral density measurements expressed as a percentage of the young adult mean (YAM) in Japan. Osteoporosis is defined as YAM <70%, and intervention is recommended at this cutoff. Because osteoporosis has a strong association with systemic metabolic disorders, we postulated that patients with YAM <70% had higher inflammatory biomarker concentrations owing to the higher systemic stress compared with YAM >70%. METHOD: We retrospectively reviewed 94 patients with low-trauma hip fractures. Blood examinations were performed on postoperative day (POD) 1 and POD 7. We used neutrophil lymphocyte ratio (NLR) and monocyte lymphocyte ratio (MLR) to evaluate postoperative recovery. After dividing the 94 patients into two groups according to a YAM cutoff of 70%, we compared the differences in NLR and MLR. RESULTS: On POD 1, patients with YAM >70% had a median NLR of 5.7 and a median MLR of 0.66, which were significantly lower than for patients with YAM <70% (8.8 and 0.9, respectively). Similarly, on POD 7, patients with YAM >70% had a median NLR of 2.0 and a median MLR of 0.31, which were significantly lower than for patients with YAM <70% (3.5 and 0.43, respectively). CONCLUSION: A YAM cutoff of 70% is an appropriate intervention threshold regarding postoperative recovery after hip fracture surgery. Mini-Abstract. Patients with YAM >70% showed lower NLR and MLR on POD 1 and POD 7. A YAM cuffoff of 70% is an appropriate intervention threshold regarding postoperative recovery after hip fracture surgery.

Risk factors for excessive postoperative sliding of femoral trochanteric fracture in elderly patients: A retrospective multicenter study.

INTRODUCTION: The application of a load on the internal fixation of a trochanteric fracture exerts a moment along the lag screw, causing the proximal bone fragment to slide along the lag screw, allowing contact between the proximal and distal bone fragments, which promotes healing. However, excessive sliding is related to poor postoperative outcomes. We aimed to identify the risk factors for excessive sliding. MATERIALS AND METHODS: We conducted a multicenter retrospective study including 115 trochanteric fractures sustained through low-energy trauma in 19 male and 96 female patients aged 60 years or older (mean age: 82.9 years) between September 2013 and December 2014. We measured the postoperative sliding distance after osteosynthesis using a sliding hip screw or intramedullary nailing, and classified participants with ≥8 mm of sliding into the excessive sliding group (ESG) and with <8 mm into non-ESG. Finally, we investigated the risk factors of excessive postoperative sliding. RESULTS: Fifty participants were classified into the ESG and 65 participants into the non-ESG. Female sex (p = 0.0264), an A3 fracture type (p = 0.0003), greater tip-apex distance (p = 0.0250), and poor reduction in either the anteroposterior or lateral radiographic views (p = 0.0156) were identified as risk factors for excessive sliding by multivariate regression analysis. CONCLUSIONS: Female sex, an unstable fracture type, a greater tip-apex distance, and a poor reduction, in either the anteroposterior or lateral views, are associated with excessive postoperative sliding. Therefore, surgery should aim to achieve good reduction and stabilization from both radiographic views.