An anatomic consideration of the femoral nerve during direct anterior hip approach: A cadaveric study.

PURPOSE: This study aimed to investigate the distance and correlation between the anatomy of the anterior side of the hip joint and the femoral nerve. METHODS: Using ten fresh-frozen cadavers with twenty hip joints. We dissected and marked the femoral nerve in the inguinal area. Employing the direct anterior approach, we identified and marked study points, including the superior and inferior points of the anterior rim of the acetabulum, » point, half point, and ¾ point along an imagined line connecting the formers, the inferomedial and mid aspect of the femoral neck, and the soft spot. Coronal plane measurements gauged the distance between these points and the femoral nerve. The collected data were analyzed to assess the distance and correlation. RESULTS: In the coronal plane, the median distance between the inferior point of the anterior rim of the acetabulum and the femoral nerve was 0 millimeters (interquartile range [IQR] 0-0). Likewise, the median distance between the mid aspect of the medial side of the femoral neck and the femoral nerve was 0 millimeters (IQR 0-0). Additionally, the mean distance between the soft spot and the femoral nerve was 1.18 cm (SD 0.63). CONCLUSION: Surgeons approaching the hip joint via the direct anterior approach should be cautious at the inferior point of the anterior rim of the acetabulum and the mid aspect of the femoral neck. The soft spot at the anterior rim of the acetabulum remains safe from direct injury when surgeons use the correct technique during anterior retractor insertion.

Development and Validation of a Risk Calculator for Intensive Care Unit Admission After Total Hip Arthroplasty.

BACKGROUND: The purpose of this study was to develop and validate a risk stratification calculator to determine the risk of a patient requiring intensive care unit (ICU) admission following primary and revision total hip arthroplasty (THA). METHODS: Using a database of 12,342 THA procedures, with 132 ICU admissions, from 2005 to 2017, we developed models of ICU admission risk based on previously identified preoperative factors including age, heart disease, neurologic disease, renal disease, unilateral versus bilateral surgery, preoperative hemoglobin, blood glucose, and smoking status. Prior to developing the calculator, a set of logistic regressions were analyzed to determine weight and scoring for each variable. Once developed, we validated the risk calculator using a second independent institution. RESULTS: A separate risk calculator was developed for primary and revision THA. The area under the curve (AUC) for primary THA was 0.808 (95% confidence interval 0.740 to 0.876) and revision THA was AUC 0.795 (confidence interval 0.740 to 0.850). As an example, the primary THA risk calculator had a Total Points scale of 220, with 50 points associated with a 0.1% chance of ICU admission and 205 points associated with a 95% chance of ICU admission. Validation with an external cohort demonstrated satisfactory AUCs, sensitivities, and specificities for both primary THA (AUC 0.794, sensitivity 0.750, and specificity 0.722) and revision THA (AUC 0.703, sensitivity 0.704, and specificity 0.671) CONCLUSION: The externally validated risk calculators developed in this study can accurately predict ICU admission following primary and revision THA based on a number of readily available preoperative factors.

Worse Outcomes Are Associated With Proximal Femoral Replacement Following Periprosthetic Joint Infection.

BACKGROUND: Proximal femoral replacements (PFRs) are often used in the setting of severe bone loss. As osteolysis has become less common, PFR may be used to address other causes of bone loss such as infection or periprosthetic fracture. The aim of this study is to investigate the clinical outcomes of PFR for non-neoplastic conditions. METHODS: A retrospective review of 46 patients undergoing PFR at a single institution was performed. The electronic records were reviewed to extract relevant information including the reason for use of PFR, surgical variables, follow-up, and complications. Survivorship curves were generated and differences in survivorship were evaluated using the log-rank test. Radiographic evaluation was also performed. RESULTS: Using revision as an endpoint, the Kaplan-Meier analysis of the entire cohort demonstrated a survival rate of 74% at 1 year and 67% at 5 years. Patients with a preoperative diagnosis of periprosthetic joint infection demonstrated the lowest survivorship with a failure rate of 47%. Furthermore, a high dislocation rate at 17.4% (n = 8) was observed. The use of dual-mobility articulation was effective in reducing dislocation. CONCLUSION: PFR is a valuable reconstructive option for patients with massive proximal femoral bone loss. This study demonstrates that patients with periprosthetic joint infection who undergo PFR reconstruction are at very high risk of subsequent failure, most commonly from reinfection and instability. The use of a dual-mobility articulation in association with PFR appears to help mitigate risk of subsequent dislocation.

The Fate of Periprosthetic Joint Infection Following Megaprosthesis Reconstruction.

BACKGROUND: A megaprosthesis may be used for reconstruction in patients with massive bone loss or a periprosthetic fracture. Periprosthetic joint infection (PJI) may occur after a megaprosthesis reconstruction and may pose a major challenge. The outcomes of managing PJI in patients with a megaprosthesis is relatively unclear. The aim of this study was to investigate the clinical course and outcomes of PJI in patients with a megaprosthesis in place. METHODS: From a total of 219 patients who underwent megaprosthesis replacement for non-oncologic conditions, 38 (17.4%) developed subsequent PJI. A retrospective review of the medical record was performed to ascertain the course of the PJI and treatment outcomes. Kaplan-Meier analysis was performed to evaluate the survival function, and the log-rank test was used to assess differences in outcome measures. RESULTS: The surgical management of 33 patients with PJI included debridement, antibiotics, and implant retention (DAIR) (82%), consisting of DAIR with modular component exchange (19 patients) and DAIR without component exchange (8 patients); 2-stage exchange arthroplasty (9%); resection arthroplasty (6%); and a single-stage revision arthroplasty (3%). The Kaplan-Meier survivorship analysis demonstrated that the overall survival rate was 65.1% at 2 years. The mortality rate was 15%, with many patients undergoing salvage procedures including amputation (18%), arthrodesis (6%), and resection arthroplasty (6%). CONCLUSIONS: The rate of PJI after megaprosthesis reconstruction, 17% in this study, appears to be very high. The management of PJI in these patients is challenging, with 1 of 3 patients undergoing failed treatment. Despite the limited options available, DAIR seems to be an appropriate treatment strategy for some of these patients. Further data on a larger cohort are needed to assess the success of various surgical procedures and predictors of failure in this challenging patient population. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Distal Femoral Replacement and Periprosthetic Joint Infection After Non-Oncological Reconstruction: A Retrospective Analysis.

BACKGROUND: Distal femoral replacement (DFR) is commonly used to manage massive bone loss around the knee arising from aseptic loosening, periprosthetic joint infection (PJI), and distal femoral fractures. A number of studies report the outcome of DFR with considerable variation in long-term survivorship. This study investigated the outcome of DFR for patients with aseptic failures, fractures, and PJI. METHODS: A retrospective review of 182 patients who underwent DFR for non-oncological indications between 2002 and 2018 was conducted. Data collected included the following: indication, postoperative complications, reoperation, revision, and follow-up. Implant survivorship with Kaplan-Meier curves along with a log-rank test for different preoperative indications was performed. A Cox regression model was used to evaluate the risk of revision. RESULTS: The overall postoperative complication rate was very high at 36%. The most common complication was PJI (17%). The rate of reoperation for any cause was 29.7%, and the revision rate was 13.7%. The most common cause of re-revision was PJI (7.1%). Revision-free survivorship of the DFR implant was 91.6% at 1 year, 87.9% at 2 years, 82.5% at 5 years, and 73.4% at 10 years. Patients who had a prior-PJI had the lowest survivorship compared to patients undergoing DFR for management of periprosthetic fracture and mechanical loosening. Additionally, the prior-PJI group was at a fourfold increased risk of postoperative PJI compared to the aseptic group. CONCLUSION: DFR is a valuable reconstructive option for patients with massive bone loss around the knee. However, patients undergoing DFR are at high risk of complications, reoperations, and failure.

N-acetylcysteine use as an adjuvant to bone cement to fight periprosthetic joint infections: A preliminary in vitro efficacy and biocompatibility study.

When antibiotic laden bone cement is used to manage periprosthetic joint infection (PJI), failure still occurs with its use in up to 30% of cases. Therefore, we designed an in vitro study to assess the bactericidal effect of N-acetylcysteine (NAC), an antibacterial adjuvant, in cement against planktonic and biofilm forms of common PJI pathogens. NAC (10%, 20%, 30%, 40%, and 50% w/v) added to polymethyl methacrylate (PMMA) and incubated in broth at 36°C. PMMA-alone and/or culture bacteria alone were used as a negative control. Aliquots of cement elution from each group were taken at 1 day and 1 week and then were investigated for antimicrobial efficacy against the planktonic-form and the biofilm-form of Staphylococcus aureus and Escherichia coli. The primary outcome was the residual colony-forming unit count. The cytotoxicity and mechanical properties of the NAC-PMMA cement-blocks were also assessed. NAC-PMMA efficacy against the planktonic bacteria was demonstrated at a minimum of 30% at Day 1 and a minimum of 20% at 1 week after (p < .001). NAC-PMMA cement was effective against biofilm at a minimum of 30% of NAC at 1 day and 1 week of cement immersion (p < .001). The PMMA alone group was identified as having the highest cytotoxicity (p < .001). NAC decreased the stiffness (p = .004) and maximum load breaking point of the cement (p = .029). NAC is an effective and biocompatible adjuvant to PMMA in terms of antibacterial activity against Staphylococcus aureus and Escherichia coli. The broad antibacterial spectrum of NAC, its low expense, and minimal cytotoxicity makes it an ideal agent for addition to PMMA cement.

Determining Diagnostic Thresholds for Acute Postoperative Periprosthetic Joint Infection.

BACKGROUND: The diagnosis of periprosthetic joint infection (PJI) in the early postoperative period remains a challenge. Although studies have established that serum C-reactive protein (CRP) and synovial markers may be useful, recent studies have suggested that the current thresholds used may lack sensitivity. The purpose of this study was to examine the role of serum CRP, erythrocyte sedimentation rate (ESR), synovial fluid white blood-cell (WBC) count, and polymorphonuclear neutrophil (PMN) percentage in the diagnosis of acute postoperative PJI and to identify the optimal threshold. METHODS: This multicenter study included patients who were investigated for possible PJI within 90 days of an index arthroplasty. This study included 197 patients from 4 institutions who underwent total joint arthroplasty from 2000 to 2017. Of these patients, 123 were confirmed to have PJI, and 74 were ruled out as not having PJI (non-infected group). Analyses of receiver operating characteristic (ROC) curves and the area under the curve were performed to determine the value of each test and optimal cutoff values. RESULTS: The optimal cutoff value was 6,130 cells/µL for synovial fluid WBC count (91% sensitivity and 83% specificity), 39.8 mg/L for serum CRP (91% sensitivity and 87% specificity), 39.5 mm/hr for ESR (76% sensitivity and 67% specificity), and 79.5% for PMN percentage (95% sensitivity and 59% specificity). Reducing the acute period from 90 days to 30 days or 45 days made little difference in most threshold values. However, the optimal cutoff for synovial fluid WBC count was almost twice as high (10,170 cells/µL) when using a 30-day definition instead of a 90-day definition. CONCLUSIONS: The calculated cutoffs in our study were substantially lower than the thresholds used by the Musculoskeletal Infection Society. The calculated values of this study should be used, as previous cutoffs may be too high and lack sensitivity. In addition, it appears that the threshold values, at least for some of the tests, change as the duration since the index arthroplasty lengthens. A continuum of threshold values that is dependent on the number of days since the index arthroplasty may need to be used for the diagnosis of acute PJI. LEVEL OF EVIDENCE: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Risk Factors for Unplanned Admission to the Intensive Care Unit After Elective Total Joint Arthroplasty.

BACKGROUND: Despite improved surgical and anesthesia techniques, as well as advances in perioperative protocols, a number of patients undergoing total joint arthroplasty (TJA) are at risk of serious medical complications that require intensive care unit (ICU) admission. With the recent move toward performing TJA in ambulatory surgical centers and on an outpatient basis, it is important to recognize patients that may require intensive care in the postoperative period. This study aimed to identify risk factors for ICU admission following elective total hip (THA) and knee (TKA) arthroplasty. METHODS: We evaluated 12,342 THA procedures, with 132 ICU admissions, and 10,976 TKA procedures, with 114 ICU admissions from 2005 to 2017. Demographic, preoperative, and surgical variables were collected and compared between cohorts using both univariate and logistic regression analysis. RESULTS: For THA, logistic regression analysis demonstrated older age, bilateral procedure, revision surgery, increased Charlson comorbidity index, general anesthesia, increased estimated blood loss, decreased preoperative hemoglobin, and increased preoperative glucose level were independently associated factors for increased risk of ICU admission. For TKA, increased age, increased body mass index, bilateral procedure, revision surgery, increased Charlson comorbidity index, increased estimated blood loss, general anesthesia, and increased preoperative glucose were independently significantly associated with ICU admission. CONCLUSION: In this study, we identify a number of critical independent risk factors which may place patients at increased risk of ICU admission following THA and TKA. Identification of these risk factors may help surgeons safely select those TJA candidates appropriate for surgery at facilities that do not have ICUs readily available.

Anterior open-wedge hepta-lateral osteotomy for severe post-traumatic genu recurvatum: a case report and review of the literature.

Severe post-traumatic genu recurvatum is an uncommon condition in orthopedics. The typical symptoms are pain, weakness, and instability. For severe and symptomatic genu recurvatum patient, the surgical correction should be performed to relieve symptoms and prevent progression of deformity. Many procedures were proposed to treat this condition, but there are some complications such as patella baja, secondary deformity, skin complication, and inadequate correction. Most of the procedures need an additional procedure such as tibial tuberosity transfer to correct the patellar height. In this case, the authors report a new technique in which the osteotomy was performed near the center of rotation angulation. And, the correction did not influence the patellar height.

Cholangiocarcinoma with spinal metastasis: Single center survival analysis.

The aim of this study was to perform a survival analysis of Cholangiocarcinoma (CCA) with spinal metastases. 55 cases of CCA with spinal metastases were retrospectively reviewed. We recorded age, sex, Kanofsky performance score, Frankel scale, number and region of affected vertebrae, presence of appendicular bone metastases, treatment received, and survival time; then performed a survival analysis. Overall median survival was 4months (95%CI, 2.89-5.11). Frankel A had the poorest survival (2months-95%CI, 1.15-2.85) compared to Frankel C and D (P=0.004 and <0.001, respectively). One-level spinal metastasis had the longest survival (8months-95%CI, 5.98-10.02) compared to two-level and more than two-level involvement (P=0.036 and 0.001, respectively). The higher Kanofsky score had the longer survival (11months-95%CI, 9.61-12.39) compared with the low and moderate score groups (P<0.001 and 0.012, respectively). Radiation therapy had a survival of 6months (95%CI, 3.41-8.59), significantly longer than the 3months for palliative spine surgery and 2months for palliative treatment alone. CCA resection and palliative spine surgery-when performed together and/or combined with other adjuvant treatment(s)-had a survival time of longer than 9months. In conclusion, CCA with spinal metastases had a poor median survival. A single level of affected spine, a Frankel scale of C or better, a moderate to high Kanofsky score, and radiation therapy were associated with significantly longer median survival. CCA resection and spinal surgery may play an important role in prolonging survival when used in conjunction with other adjuvant treatment modalities.

The Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ): A validation of the reliability of the Thai version.

BACKGROUND: The Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ) was developed by the Japanese Orthopedic Association (JOA) for assessment of lower back pain and lumbar spinal disease. We aimed to translate the JOABPEQ into Thai and test its reliability and validity in the Thai context. METHODS: The original JOABPEQ was translated into Thai in accordance with international recommendations. Then 180 lumbar spinal disease patients (mean age 58.58 ± 11.97, 68.3% female) were asked to complete the Thai version of the JOABPEQ twice at 2-week intervals. Test-retest reliability was analyzed using the intra-class correlation coefficient (ICC). Internal consistencies were analyzed using Cronbach's alpha, while the construct validity was compared with the Thai version of the modified SF-36, and tested using the Spearman's rank correlation coefficient. RESULTS: The Thai JOABPEQ showed satisfactory test-retest reliability in all parameters (Intra-class Correlation Coefficient 0.761-0.862). The variables low back pain, walking ability, social life function, and mental health had satisfactory internal consistency (the respective Cronbach's α was 0.798, 0.721, 0.707, and 0.795). Only the lumbar function parameter showed moderate reliability (Cronbach's α = 0.654). All of the variables in the Thai JOABPEQ had a statistically positive correlation with the correspondent Thai SF-36 subscales (Spearman's rank correlation p value < 0.05). CONCLUSION: The Thai version of JOABPEQ had satisfactory internal consistency, test-retest reliability, and construct validity; it can be used as a reliable tool for assessing quality of life for lumbar spinal disease patients in Thailand.

Cross-cultural adaptation and validation of the reliability of the Thai version of the Hip disability and Osteoarthritis Outcome Score (HOOS).

HOOS was developed as an extension of the Western Ontario and McMaster Universities' Osteoarthritis Index questionnaire for measuring symptoms and functional limitations related to the hip(s) of patients with osteoarthritis. To determine the validity and reliability of the Thai version of the Hip disability and Osteoarthritis Outcome Score (HOOS) vis-à-vis hip osteoarthritis, the original HOOS was translated into a Thai version of HOOS, according to international recommendations. Patients with hip osteoarthritis (n = 57; 25 males) were asked to complete the Thai version of HOOS twice: once then again after a 3-week interval. The test-retest reliability was analyzed using the intraclass correlation coefficient (ICC). Internal consistencies were analyzed using Cronbach's alpha, while the construct validity was tested by comparing the Thai HOOS with the Thai modified SF-36 and calculating the Spearman's rank correlation coefficients. The Thai HOOS produced good reliability (i.e., the ICC was greater than 0.9 in all five subscales). All of the Cronbach's alpha showed that the Thai HOOS had high internal consistency (Cronbach's alpha greater than 0.8), especially for the pain and ADL subscales (0.89 and 0.90, respectively). The Spearman's rank correlation for all five subscales of the Thai HOOS had moderate correlation with the Bodily Pain subscale of the Thai SF-36. The pain subscale of the Thai HOOS had a high correlation with the Vitality and Social Function subscales of the Thai SF-36 (r = 0.55 and 0.54)-with which the symptom subscale had a moderate correlation. The Thai version of HOOS had excellent internal consistency, excellent test-retest reliability, and good construct validity. It can be used as a reliable tool for assessing quality of life for patients with hip osteoarthritis in Thailand.

Validation of the reliability of the Thai version of the Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ).

BACKGROUND: The Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) was developed to resolve problems associated with the original evaluation of cervical myelopathic patients. The aim of this study was to translate the JOACMEQ into Thai as per international recommendations, and to test its reliability and validity in the Thai context METHODS: The JOACMEQ was translated into Thai, using international guidelines. Cervical myelopathy patients (n = 70; 31 males) were asked to complete the Thai version JOACMEQ twice (4 weeks apart). Test-retest reliability was analyzed using the intra-class correlation coefficient (ICC). Internal consistencies were analyzed using Cronbach's alpha, while the construct validity was compared with the Thai version modified SF-36; using the Spearman's rank correlation coefficient. RESULTS: The Thai JOACMEQ produced good reliability (i.e., the ICC was >0.9 in 2 parameters and >0.8 in one). Overall the Cronbach's α for the 24 questions showed very high internal consistency (Cronbach's α > 0.8) and almost all Cronbach's α showed satisfactory internal consistency except for bladder function. The Spearman's rank correlation for all the JOACMEQ parameters had a positive correlation with all Thai SF 36 subscales, especially the quality of life parameter, which showed a strong correlation with all SF-36 subscales. CONCLUSION: The Thai version of the JOACMEQ had satisfactory internal consistency and test-retest reliability: it also had good construct validity. It can therefore be used as a reliable tool for assessing quality of life for cervical myelopathy patients in Thailand.

Interrater Reliability of the Postoperative Epidural Fibrosis Classification: A Histopathologic Study in the Rat Model.

STUDY DESIGN: Agreement study. PURPOSE: To validate the interrater reliability of the histopathological classification of the post-laminectomy epidural fibrosis in an animal model. OVERVIEW OF LITERATURE: Epidural fibrosis is a common cause of failed back surgery syndrome. Many animal experiments have been developed to investigate the prevention of epidural fibrosis. One of the common outcome measurements is the epidural fibrous adherence grading, but the classification has not yet been validated. METHODS: Five identical sets of histopathological digital files of L5-L6 laminectomized adult Sprague-Dawley rats, representing various degrees of postoperative epidural fibrous adherence were randomized and evaluated by five independent assessors masked to the study processes. Epidural fibrosis was rated as grade 0 (no fibrosis), grade 1 (thin fibrous band), grade 2 (continuous fibrous adherence for less than two-thirds of the laminectomy area), or grade 3 (large fibrotic tissue for more than two-thirds of the laminectomy area). A statistical analysis was performed. RESULTS: Four hundred slides were independently evaluated by each assessor. The percent agreement and intraclass correlation coefficient (ICC) between each pair of assessors varied from 73.5% to 81.3% and from 0.81 to 0.86, respectively. The overall ICC was 0.83 (95% confidence interval, 0.81-0.86). CONCLUSIONS: The postoperative epidural fibrosis classification showed almost perfect agreement among the assessors. This classification can be used in research involving the histopathology of postoperative epidural fibrosis; for example, for the development of preventions of postoperative epidural fibrosis or treatment in an animal model.