Optimal reimplantation timing in two-stage exchange for periprosthetic joint infection: an observative cohort study in Asian population.

BACKGROUND: The optimal timing for reimplantation for periprosthetic joint infection (PJI) has not been established and varies from a few weeks to several months. The aim of this study was to assess the commendable time between implant removal and reimplantation in patients who underwent two-stage exchange arthroplasty for PJI. METHODS: We retrospectively reviewed 361 patients who were treated with two-stage exchange arthroplasty for hip and knee chronic PJI at our institution between January 2000 and December 2018. Patient characteristics, comorbidities, surgical variables, microbiology data, and time to reimplantation were recorded. All patients were followed for a minimum of one year. Treatment failure was defined by Delphi criteria. Logistic regression analyses were used to calculate survival rates and adjusted odds ratios (ORs) of treatment failure. RESULTS: In final analysis, 27 (7.5%) had treatment failure. Factors related to treatment failure including interim spacer exchange (OR, 3.13; confidence interval (CI), 1.04-9.09, p = 0.036), higher ESR level at reimplantation (OR, 1.85; CI, 1.05-3.57; p = 0.04), and time to reimplantation (OR, 1.00; CI, 1.003-1.005, p = 0.04). Performing revision arthroplasty surgery from 16 to 20 weeks had highest successful rate. The reimplantation over 24 weeks had a lower successful rate. However, no statistical significance in comparing each interval group. CONCLUSION: Our study emphasized the importance of timely reimplantation in achieving successful outcomes. Factors such as ESR levels, spacer exchange, and the duration of time to reimplantation influenced the likelihood of treatment failure in two-stage exchange arthroplasty for hip and knee PJI.

Short-term clinical outcomes of transarterial embolization for symptomatic hand osteoarthritis refractory to conservative treatment.

PURPOSE: The present study aims to assess the short-term clinical outcomes and safety of transarterial embolization (TAE) for symptomatic hand osteoarthritis (OA) refractory to conservative treatment. METHODS: The present retrospective cohort pilot study included nine patients who underwent TAE for symptomatic OA-associated hand pain in a single tertiary center between November 2022 and January 2023. The baseline and post-procedural OA-associated hand pain and function were assessed using the visual analog scale (VAS) and the Australian Canadian Hand Osteoarthritis Index (AUSCAN). The use of conservative treatment and pain medications was also recorded. Post-procedural adverse events were evaluated according to the Society of Interventional Radiology classification. RESULTS: Compared with the baseline, the overall VAS scores were significantly decreased at 1-week, 1-month, 3-months, and 6-months after TAE (76 ± 15 mm versus 34 ± 18 mm, P < 0.001; 32 ± 11 mm, P < 0.001; 21 ± 15 mm, P < 0.001; 18 ± 19 mm, P = 0.002). Similarly, improvement in the mean total AUSCAN scores (22.0 ± 10.0 versus 13.2 ± 6.6, P = 0.007; 14.11 ± 7.3, P = 0.004; 9.8 ± 6.8, P = 0.004; 9.3 ± 7.4, P = 0.011) were documented. The use of other conservative treatment methods also gradually decreased. There were no severe adverse events reported during the follow-up period. CONCLUSION: TAE is a feasible and safe treatment method for symptomatic hand OA refractory to conservative treatment. This minimally invasive procedure effectively relieves debilitating OA-associated joint pain and restores hand function with a durable treatment effect.

Predicting the Risk of Total Hip Replacement by Using A Deep Learning Algorithm on Plain Pelvic Radiographs: Diagnostic Study.

BACKGROUND: Total hip replacement (THR) is considered the gold standard of treatment for refractory degenerative hip disorders. Identifying patients who should receive THR in the short term is important. Some conservative treatments, such as intra-articular injection administered a few months before THR, may result in higher odds of arthroplasty infection. Delayed THR after functional deterioration may result in poorer outcomes and longer waiting times for those who have been flagged as needing THR. Deep learning (DL) in medical imaging applications has recently obtained significant breakthroughs. However, the use of DL in practical wayfinding, such as short-term THR prediction, is still lacking. OBJECTIVE: In this study, we will propose a DL-based assistant system for patients with pelvic radiographs to identify the need for THR within 3 months. METHODS: We developed a convolutional neural network-based DL algorithm to analyze pelvic radiographs, predict the hip region of interest (ROI), and determine whether or not THR is required. The data set was collected from August 2008 to December 2017. The images included 3013 surgical hip ROIs that had undergone THR and 1630 nonsurgical hip ROIs. The images were split, using split-sample validation, into training (n=3903, 80%), validation (n=476, 10%), and testing (n=475, 10%) sets to evaluate the algorithm performance. RESULTS: The algorithm, called SurgHipNet, yielded an area under the receiver operating characteristic curve of 0.994 (95% CI 0.990-0.998). The accuracy, sensitivity, specificity, and F1-score of the model were 0.977, 0.920, 0932, and 0.944, respectively. CONCLUSIONS: The proposed approach has demonstrated that SurgHipNet shows the ability and potential to provide efficient support in clinical decision-making; it can assist physicians in promptly determining the optimal timing for THR.

Influence of the Type of Bone Cement Used in Two-Stage Exchange Arthroplasty for Chronic Periarticular Joint Infection on the Spacer Replacement and Reinfection Rate.

BACKGROUND: Antibiotic-loaded bone cement (ALBC) spacers are used in the first stage when treating periprosthetic joint infection (PJI). This study aimed to investigate whether a spacer made from commercial ALBC or plain bone cement with additional antibiotics could affect the spacer exchange rate before reimplantation. METHODS: Patients undergoing two-stage exchange arthroplasty due to chronic PJI from January 2014 to August 2021 were retrospectively reviewed. The exclusion criteria included arthroplasty in the setting of septic arthritis, megaprosthesis, atypical pathogen infection, spacer placement unrelated to PJI, and spacer exchange due to mechanical complications. The patient demographics, brand of cement, and microbiology were recorded manually. The primary outcome was the incidence of spacer exchange due to persistent infection and the secondary outcome was the incidence of reinfection after reimplantation. A multivariate logistic regression analysis and Chi-square test were conducted to identify the effect of cement type on the spacer exchange. RESULTS: A total of 334 patients underwent two-stage exchange arthroplasty for PJI. The spacer exchange rates in the commercial and non-commercial ALBC groups were 6.4% and 25.1%, respectively (p = 0.004). After controlling for confounding factors, there were significant differences between the commercial group and non-commercial groups in the spacer exchange rate (adjusted OR = 0.25; 95% CI = 0.72-0.87, p = 0.029). The use of commercial ALBC was not associated with a lower reinfection rate after reimplantation (p = 0.160). CONCLUSIONS: In a two-stage exchange arthroplasty scenario, the spacer comprised of commercial ALBC resulted in a lower spacer exchange rate than the plain bone cement, both of which had additional antibiotics. However, the use of commercial ALBC was not associated with a lower incidence of reinfection following reimplantation.

Association of Nitric Oxide Synthase Polymorphism and Coagulopathy in Patients with Osteonecrosis of the Femoral Head.

Genetic polymorphism of nitric oxide synthase (NOS) can cause reduction of nitric oxide (NO) levels and may be associated with osteonecrosis of the femoral head (ONFH). However, the association of coagulopathy and NOS polymorphism in ONFH patients has not been confirmed. Between November 2005 and October 2013, 155 patients with ONFH were recruited in the study of serum coagulation profiles and NOS polymorphism. Another 43 patients who had dysplasia, osteoarthritis, or trauma of hip joints were included as controls. PCR genotyping for the analysis of NOS 27-bp polymorphism in intron 4 was performed. The analysis of coagulation profiles included fibrinogen, fibrinogen degradation product (FDP), protein S, protein C, and anti-thrombin III. The results showed that 27-bp repeat polymorphism was significantly associated with ONFH (OR 4.32). ONFH patients had significantly higher fibrinogen, FDP, protein S, and anti-thrombin III levels than that of the controls. The incidence of coagulopathy was significantly higher in ONFH patients (73.2%), and the odds ratio increased from 2.38 to 7.33 when they had 27-bp repeat polymorphism. Patients with hyperfibrinogenemia, elevated FDP levels, and with the risk factor of alcohol or steroid use had significantly higher risks of bilateral hip involvement. This study demonstrated the presence of NOS polymorphism, and a resultant reduction in NO production was associated with coagulopathy, which in turn might contribute to higher risks of bilateral ONFH. Our data suggests that checking NOS polymorphism and coagulopathy may provide a new avenue in managing ONFH.

Which Minor Criteria is the Most Accurate Predictor for the Diagnosis of Hip and Knee Periprosthetic Joint Infection in the Asian Population?

BACKGROUND: The aim of this study was to evaluate the diagnostic performance of minor criteria from the 2018 International Consensus Meeting (ICM) for the diagnosis of chronic periprosthetic joint infection (PJI) in an Asian population. METHODS: We retrospectively reviewed 76 patients who underwent a revision knee or hip arthroplasty at an academic institution between September 2018 and December 2019. All major and minor 2018 ICM criteria were available for all patients included. Cases with at least 1 major criterion or score ≥6 in minor criteria were considered as infected. The diagnostic performance was evaluated by a receiver operative characteristic curve analysis and area under the curve (AUC) for each minor criterion. An AUC value of more than 0.9 was considered outstanding and 0.8-0.9 as excellent. RESULTS: When using 2018 ICM threshold, the diagnostic performance ranked based on AUC was the following: alpha defensin (0.92), positive histology (0.83), leukocyte esterase (0.82), synovial white blood cell (0.81), serum erythrocyte sedimentation rate (0.78), synovial polymorphonuclear neutrophils (0.77), serum C-reactive protein (0.74), D-dimer (0.59), single positive culture (0.53), and positive intraoperative purulence (0.51). Alpha defensin was considered as an outstanding test among the 2018 ICM minor criteria. Positive histology, leukocyte esterase, and synovial white blood cell were considered as excellent tests. CONCLUSION: Based on our findings, alpha-defensin has the best diagnostic performance in Asian population among the minor criteria of 2018 ICM.

Impaction Bone Grafting Augmented With a Wire Coil by the Lightbulb Technique for Osteonecrosis of the Femoral Head.

BACKGROUND: Osteonecrosis of the femoral head (ONFH) is a debilitating disease that primarily affects the hips of young adults. The purpose of this study is to report the mid-term results of impaction bone grafting augmented with a wire coil using the lightbulb technique for ONFH. METHODS: From 1998 to 2016, 50 hips with late precollapsed or early postcollapsed ONFH (28 hips with Association Research Circulation Osseous [ARCO] IIC and 22 with IIIA) were treated by impaction bone grafting augmented with a wire coil using the lightbulb technique. The survival rate was analyzed with conversion to total hip arthroplasty (THA) as the end point. RESULTS: Thirty-one of the 50 hips had a successful clinical result without conversion to THA at a mean follow-up of 109.2 months. The 5-year survival rate was 68%, 82.1%, and 50% for the entire cohort, ARCO stage IIC, and ARCO stage IIIA, respectively. The 19 hips that had failed were converted to THA at an average of 52.8 months. The multivariable Cox proportional hazards model showed that an ARCO stage IIIA disease, a lateral lesion, and a necrotic index ≥0.67 were the independent risk factors for conversion to THA. CONCLUSION: As a head-preserving procedure, the lightbulb technique using impaction bone grafting augmented with a wire coil is worthwhile for patients in an earlier stage of disease and smaller lesion size to postpone the need for THA.

Zoledronic Acid Ameliorates the Bone Turnover Activity and Periprosthetic Bone Preservation in Cementless Total Hip Arthroplasty.

The administration of zoledronic acid (ZA) to patients who received cementless total hip arthroplasty (THA) has been reported to reduce bone turnover markers (BTMs) and increase bone mineral density (BMD). The effects of two-dose ZA versus placebo on cementless THA patients were analyzed in this five-year extension study. Alkaline phosphatase (ALP), osteocalcin (OC), procollagen 1 intact N-terminal propeptide (P1NP), serum calcium, renal function, radiological findings, and functional outcomes were compared in 49 patients, and the periprosthetic BMD of seven Gruen zones were compared in 19 patients. All the patients had normal renal function and calcium levels at their final follow-up. The mean ALP level in the ZA group was significantly lower at the fifth year, mean OC levels were significantly lower at the second and fifth year, and mean P1NP levels were significantly lower from 6 weeks to 5 years as compared with the control group. Fifth-year BMD levels were not found to be different between the ZA and control groups. The BMD Change Ratios in the ZA group were significantly increased in Gruen zone 6 at 1, 2, and 5 years. Our study results suggest that short-term ZA treatment with a subsequent 4-year drug holiday may inhibit serum BTMs and provide periprosthetic bone preservation at five years without adverse events.

The Risk of Bleeding and Adverse Events with Clopidogrel in Elective Hip and Knee Arthroplasty Patients.

Orthopedic surgeons often face a clinical dilemma on how to manage antiplatelet therapies during the time of surgery. This retrospective study is aimed to investigate the bleeding risk and adverse events in patients who hold or keep clopidogrel during elective major joints arthroplasty. Two hundred and ninety-six patients that were treated with clopidogrel while undergoing total hip or knee joint replacement between January 2009 and December 2018 were studied. Group 1 included 56 patients (18.9%) who kept using clopidogrel preoperatively. Group 2 included 240 patients who hold clopidogrel use ≥5 days preoperatively. Blood transfusion rates, estimated blood loss, complication rates, and adverse cardiocerebral events were collected and analyzed. The mean total blood loss was more in the group 1 patients as compared with that in the group 2 patients (1212.3 mL (685.8 to 2811.8) vs. 1068.9 mL (495.6 to 3294.3), p = 0.03). However, there was no significant difference between the two groups of patients regarding transfusion rates, bleeding-related complications, and infection rates. There was a trend toward a higher incidence of adverse cardiocerebral events in patients withholding clopidogrel for more than 5 days before surgery. The results of this study suggest that clopidogrel continuation could be safe and advisable for patients at thrombotic risk undergoing primary major joint replacement. Acute antiplatelet withdrawal for an extended period of time might be associated with an increased risk of postoperative thromboembolic events. More studies are required in the future to further prove this suggestion.

Outcome and Predictors of Septic Failure Following Total Joint Arthroplasty for Prior Septic Arthritis of Hip and Knee Joint.

BACKGROUND: Arthroplasty patients with prior septic arthritis are at a high risk of developing periprosthetic joint infection (PJI). The aims of this study are to investigate the outcome and predictors of septic failure following total joint arthroplasty (TJA) for prior septic arthritis. In addition, the optimal timing of TJA is also discussed. METHODS: A retrospective review of 105 TJA patients with prior septic arthritis between January 2000 and December 2019 was performed. Patient-specific and surgery-related factors, organism profiles, and other relevant variables were recorded. RESULTS: At a mean follow-up of 10.3 years, the PJI rate was 16.2%. The adjusted Cox proportional hazards model showed that male gender (HR, 9.95; P < .01), end-stage renal disease (HR, 37.34; P < .01), debridement surgery ≥3 times (HR,4.75; P = .04) and polymicrobial infection in primary septic arthritis (HR, 10.02; P = .02) were independent risk factors for PJI. Neither the types of initial debridement, nor one-stage vs two-stage arthroplasty was related to the risk of PJI. While delaying the timing of TJA did not correlate with a reduction of PJI rate, there was a higher risk of PJI re-infection by the same microorganisms isolated in prior septic arthritis if TJA was performed within 6 months after septic arthritis. CONCLUSIONS: Our study demonstrated that male gender, end-stage renal disease (ESRD), multiple debridement surgeries and polymicrobial septic arthritis predisposed septic failure of TJA following prior septic arthritis. Surgeons should counsel patients with the potential complications, and be cognizant about the risk factors pertaining to septic failure when considering TJA.

Automatic Hip Detection in Anteroposterior Pelvic Radiographs-A Labelless Practical Framework.

Automated detection of the region of interest (ROI) is a critical step in the two-step classification system in several medical image applications. However, key information such as model parameter selection, image annotation rules, and ROI confidence score are essential but usually not reported. In this study, we proposed a practical framework of ROI detection by analyzing hip joints seen on 7399 anteroposterior pelvic radiographs (PXR) from three diverse sources. We presented a deep learning-based ROI detection framework utilizing a single-shot multi-box detector with a customized head structure based on the characteristics of the obtained datasets. Our method achieved average intersection over union (IoU) = 0.8115, average confidence = 0.9812, and average precision with threshold IoU = 0.5 (AP50) = 0.9901 in the independent testing set, suggesting that the detected hip regions appropriately covered the main features of the hip joints. The proposed approach featured flexible loose-fitting labeling, customized model design, and heterogeneous data testing. We demonstrated the feasibility of training a robust hip region detector for PXRs. This practical framework has a promising potential for a wide range of medical image applications.

Comparison of Effects of a Thrombin-Based Hemostatic Agent and Topical Tranexamic Acid on Blood Loss in Patients with Preexisting Thromboembolic Risk Undergoing a Minimally Invasive Total Knee Arthroplasty. A Prospective Randomized Controlled Trial.

BACKGROUND: The efficacy of a thrombin-based hemostatic agent (Floseal®) on reducing postoperative blood loss after total knee arthroplasty (TKA) was still unclear. The aim of our study was to conduct a prospective randomized controlled study to compare the blood conservation effects of Floseal® and topical TXA in patients with preexisting thromboembolic risk undergoing primary minimally invasive TKA. METHODS: Our power analysis of this study was based upon the following description, to obtain a statistical power of 0.90 and an alpha error of 0.05, 30 patients were required in each group. Therefore, we enrolled a total of 103 patients with at least one of the risk factors for thromboembolism who underwent unilateral primary minimally invasive TKA, and the participants were randomly divided into the topical TXA group (n = 34), receiving intra-articular injection of 3 g of TXA in 100 mL saline after TKA, the topical Floseal® group (n = 34), receiving 10 mL of Floseal® intra-articularily during surgery, and the placebo group (n = 35), receiving an intra-articular saline injection only. The total blood loss (TBL) and hemoglobin (Hb) drop were compared among the 3 groups. RESULTS: The TXA group had a lower TBL of 645 mL (227 to 1090) in comparison with 1145 mL (535 to 1942) in the Floseal® group and 1103 mL (424 to 1711) in the placebo (p < 0.001, respectively). The TBL was similar between the Floseal® group and the placebo group (p = 0.819). No patients in any group had symptoms of venous thromboemblism. CONCLUSION: Our prospective randomized controlled study showed that intra-articular application of TXA was superior to hemostatic matrix (Floseal®) in terms of blood conservation in patients with preexisting thromboembolic risk undergoing minimally invasive TKA. This trial is registered with Clinicaltrials.gov (NCT02865174) on 08/09/2016.

Does preoperative dipyridamole-thallium scanning reduce 90-day cardiac complications and 1-year mortality in patients with femoral neck fractures undergoing hemiarthroplasty?

BACKGROUND: This study aimed to evaluate the effect of dipyridamole-thallium scanning (DTS) on the rates of 90-day cardiac complications and 1-year mortality in patients with a femoral neck fracture treated with hemiarthroplasty. METHODS: Between 2008 and 2015, 844 consecutive patients who underwent cemented or cementless hemiarthroplasty were identified from the database of a single level-one medical center. One-hundred and thirteen patients (13%) underwent DTS prior to surgery, and 731 patients (87%) did not. Patient characteristics, comorbidities, surgical variables, and length of the delay until surgery were recorded. A propensity score-matched cohort was utilized to reduce recruitment bias in a 1:3 ratio of DTS group to control group, and multivariate logistic regression was performed to control confounding variables. RESULTS: The incidence of 90-day cardiac complications was 19.5% in the DTS group and 15.6% in the control group (p = 0.343) among 452 patients after propensity score-matching. The 1-year mortality rate (10.6% vs 13.3%, p = 0.462) was similar in the two groups. In the propensity score-matched patients, utilization of DTS was not associated with a reduction in the rate of 90-day cardiac complications (matched cohort, adjusted odds ratio [aOR] = 1.32; 95% confidence interval [CI] 0.75-2.33, p = 0.332) or the 1-year mortality rate (aOR = 0.62; 95% CI 0.27-1.42, p = 0.259). Risk factors for cardiac complications included an American Society of Anesthesiologists grade ≥ 3 (OR 3.19, 95% CI 1.44-7.08, p = 0.004) and pre-existing cardiac comorbidities (OR 5.56, 95% CI 3.35-9.25, p < 0.001). Risk factors for 1-year mortality were a long time to surgery (aOR 1.15, 95% CI 1.06-1.25, p = 0.001), a greater age (aOR 1.05, 95% CI 1.00 to 1.10, p = 0.040), a low body mass index (BMI; aOR 0.89, 95% CI 0.81-0.98, p = 0.015), and the presence of renal disease (aOR 4.43, 95% CI 1.71-11.46, p = 0.002). DISCUSSION: Preoperative DTS was not associated with reductions in the rates of 90-day cardiac complications or 1-year mortality in patients with a femoral neck fracture undergoing hemiarthroplasty. The necessity for DTS should be re-evaluated in elderly patients with femoral neck fractures, given that this increases the length of the delay until surgery. LEVEL OF EVIDENCE: Prognostic level III.

Correction to: Treatment of cam-type femoroacetabular impingement using anterolateral mini-open and arthroscopic osteochondroplasty.

In the original publication of this article [1], the first name of the 5th author is wrong.

Mechanical failure of articulating polymethylmethacrylate (PMMA) spacers in two-stage revision hip arthroplasty: the risk factors and the impact on interim function.

BACKGROUND: This study aimed to investigate the risk factors for mechanical failure of cement spacers and the impact on hip function after two-stage exchange arthroplasty for periprosthetic joint infection (PJI). METHODS: Thirty-one patients (19 males and 12 females) with hip PJIs underwent resection arthroplasty and implantation of cement spacers from January 2014 to December 2015. Patients who encountered spacer-associated mechanical complications in the interim period (14 of 31) were compared with those without complications (17 of 31). Complications were defined as spacer dislocation, spacer fracture, spacer fracture with dislocation, and femoral fracture during or following spacer implantation. Hip functional outcome was assessed using the Harris hip score (HHS). Treatment success was defined according to the following criteria: (1) no symptoms or signs indicative of infection; (2) no PJI-related mortality; and (3) no subsequent surgical intervention for infection after reimplantation surgery. Multivariate logistic regression and Kaplan-Meier survival curves were used for analysis. RESULTS: Fourteen patients (14/31 = 45%) suffered at least one spacer-related complication within the interim period. The development of spacer complications was associated with a younger age (odds ratio [OR] 0.91, 95% confidence interval [CI] 0.83-1.00, p = 0.045) and chronic PJI (OR 14.7, 95% CI 1.19-182, p = 0.036). Patients with spacer complications also had a lower median HHS (37 vs. 60, p < 0.001) before reimplantation in comparison to those without spacer complications. After reimplantation, the two groups had a similar median HHS (90 vs. 89, p = 0.945). Two patients did not undergo reimplantation due to extensive comorbidities, and subsequently retained the antibiotic spacer for definitive treatment. The 2-year treatment success rate was 84.6% in the spacer-complication group and 87.5% in the non-spacer-complication group (p = 0.81). CONCLUSION: There was a high complication rate for articulating PMMA spacers during the interim period of two-stage revision total hip arthroplasty. A young age and chronic infection were the primary risk factors associated with mechanical complications. Patients at high risk of spacer-related mechanical complications should be advised accordingly by surgeons. Knowing the possible risk factors, surgeons should educate patients thoroughly to avoid spacer complications, thereby increasing patient satisfaction in the interim stage. LEVEL OF EVIDENCE: Prognostic Level III.

Treatment of cam-type femoroacetabular impingement using anterolateral mini-open and arthroscopic osteochondroplasty.

BACKGROUND: Femoroacetabular impingement (FAI) is associated with decreased hip function and early hip osteoarthritis. Surgical treatment is often required to halt the process of mechanical degeneration. The study investigated the short-to-midterm results of using a modified anterolateral mini-open and arthroscopic osteochondroplasty in the treatment of cam-type FAI. METHODS: Thirty-six patients (39 hips), with the mean age of 43.6 years, who had cam-type FAI, were operated by a mini-open and arthroscopy-assisted osteochondroplasty via the Watson-Jones interval between 2002 and 2016. Radiographic parameters and Harris hip scores were retrospectively analyzed after a mean follow-up of 44 months. RESULTS: Of the 39 hips, the mean Harris hip score significantly improved from 61.1 preoperatively to 84.2 postoperatively (P < 0.01). There were nine hips (23%) undergoing total hip arthroplasty (THA) at a mean of 22 months (range, 3~64 months) due to progression of hip osteoarthritis. The 5-year survival for hip preserving was 74.9%. Cox proportional-hazards model showed that age ≥ 55 years (P = 0.03) and preoperative Tönnis stage II (P = 0.02) were independent risk factors for conversion to THA. CONCLUSIONS: The mini-open and arthroscopic approach allowed direct visualization and improved quality of the osteochondroplasty of FAI hip while avoiding the need for surgical dislocation. This technique could be a safe and viable option for symptomatic cam-type FAI patients to relieve symptoms and improve hip function.

Long-term outcomes of Phemister bone grafting for patients with non-traumatic osteonecrosis of the femoral head.

BACKGROUND: Phemister procedure is an effective treatment for early stage osteonecrosis of femoral head (ONFH). Since the long-term results of the Phemister procedure are less reported in the literature, the purpose of this study was to investigate the long-term outcomes of this bone grafting technique in patients with earlier stages of ONFH. METHODS: From 1994 to 2010, 29 hips with pre-collapsed or early collapsed (< 2 mm) ONFH treated by Phemister procedure were evaluated. Among them, nine hips were Association Research Circulation Osseous (ARCO) stage IIA, 13 stage IIB, 4 stage IIC, and 3 stage IIIA. The mean age was 38.9 years. The mean follow-up was 14 years (1-21 years). Survivorship was analyzed with conversion to total hip arthroplasty (THA) as the endpoint. RESULTS: At the final follow-up, 10 hips underwent THA at a mean of ten years (1-18 years). The overall clinical success rate for hip preserving was 65.5%, and radiological success rate was 31%. The mean Harris Hip Score improved from 50.3 to 76.1. The survival of hips was significantly inferior in female patients (P < 0.01), ARCO stage III disease (P = 0.03), lateral type lesion (P < 0.01), and necrotic index ≥ 0.67 (P < 0.01). The Cox proportional hazards model showed that gender, ARCO stage, and necrotic index were independent risk factors for conversion to THA. CONCLUSION: The study showed acceptable results without complication in patients receiving Phemister procedure for early stage ONFH at a mean follow-up of 14 years. As a head-preserving procedure, Phemister technique is worthwhile for young patients to postpone the need for THA.

Plasma D-dimer is not useful in the prediction of deep vein thrombosis after total knee arthroplasty in patients using rivaroxaban for thromboprophylaxis.

BACKGROUND: Venous thromboembolism (VTE) is a serious complication following total joint replacement. The use of rivaroxaban, a highly selective and direct factor Xa inhibitor, has been used widely as a safe and efficacious way to prevent VTE after total joint replacements. However, little is known about the diagnostic efficacy of plasma D-dimer test on deep vein thrombosis (DVT) in patients using rivaroxaban for thromboprophylaxis. The study is aimed to investigate the trend and the diagnostic efficacy of D-dimer test on DVT in patients with primary total knee arthroplasty (TKA) using rivaroxaban for thromboprophylaxis. METHODS: Two hundred TKA patients using rivaroxaban postoperatively as chemical prophylaxis were reviewed. D-dimer levels were checked at 4 h after the surgery and on postoperative days 1 and 4. Venography was used to document the presence of DVT. The Mann-Whitney U test was used to detect the differences in the D-dimer levels at different time points in patients with and without DVT, followed by Bonferroni corrections for p values. Receiver operating characteristics (ROC) curves were constructed to determine the best cutoff values of the D-dimer test at each time point after the surgery. RESULTS: Twenty-nine of the 200 patients were found to have deep vein thrombosis by venography, resulting in an incidence of 14.5%. All patients with DVTs occurred in the distal calf veins, and only one patient was symptomatic. We found significant differences in D-dimer concentration between patients with and without DVT at postoperative day 4. The best cutoff value determined by receiver operating characteristics analysis was 3.8 mg/L at postoperative day 4, with an AUC equal to 63.5%, and a sensitivity, specificity, PPV, and NPV of 58.6, 76, 29.3, and 91.5%, respectively. CONCLUSIONS: Rivaroxaban was effective on reducing DVT in patients undergoing TKA. Because all the DVTs occurred in the leg veins, decreased thrombus volume and size might result in poor accuracy of plasma D-dimer test in prediction or diagnosis of postoperative DVT.

Structural and Morselized Allografting Combined with a Cementless Cup for Acetabular Defects in Revision Total Hip Arthroplasty: A 4- to 14-Year Follow-Up.

Using morselized and structural allograft to restore bone stock for massive acetabular bone defect in revision total hip arthroplasty (THA) is an appealing procedure. However, concerns about inability to achieve long-term stability following allograft resorption remained. From 2003 to 2012, 59 hips in 58 patients undergoing revision THA for Paprosky type II or III acetabular defects were retrospectively reviewed. The acetabular defects were managed with deep-frozen morselized and structural allografts, and a press-fit cementless cup along with supplementary screws. Clinical outcomes and radiographic results were analyzed with a mean follow-up of 8.7 years. The clinical successful rate was 100% for hips with Paprosky type II defect, 95.2% for IIIA defect, and 92.8% for IIIB defect. Three hips with type III defect failed at 4, 7, and 9 years, respectively. Harris Hip Score improved significantly from 60.1 preoperatively to 91.3 at the latest follow-up. All hips with good clinical results showed trabecular bridging in the allograft-host bone interface. Deep-frozen structural and morselized allograft in combination with a press-fit cementless cup represented a viable option to reconstruct acetabular defects in revision THA.