Treatment of Vancouver Type B Periprosthetic Femoral Fractures Using Cortical Strut Allografts.

Introduction: The optimal surgical treatment for Vancouver B2 and B3 fractures has not been determined, and bone defects and delays in fracture healing significantly affect treatment outcomes. Some authors have argued that when a serious bone defect is present, the use of cortical strut allografts for the treatment of type B2 and B3 periprosthetic femoral fractures (PFFs) after hip joint replacement may be beneficial. This study aimed to determine the usefulness of cortical strut allografts based on mid-to long-term clinical radiologic results after surgical treatment of Vancouver B-type PFFs. Methods: We retrospectively reviewed the outcomes of 48 patients with postoperative PFFs. The mean duration of follow-up was 6.7 years. The 22 patients were treated with cortical strut allograft. Each case was characterized and described in detail, including the length of allograft and the union period, and possible correlations between allograft length and strut-to-host bone union were analyzed. Clinical evaluations included Parker mobility and Harris hip scores. At the final follow-up, we assessed the radiological results using the Beals and Tower's criteria, stem subsidence, and fracture union time. Results: All 48 fractures united at an average of 21.5 weeks, and strut-to-host bone union was typically observed within 32 months. No positive correlation was identified between the allograft length and incorporation period. There was one deep infection and four cases of dislocation, but there was no fracture or malunion of the cortical strut allografts. No evidence of femoral loosening was observed in any of the patients. Conclusion: Cortical strut allografts used to treat type B PFFs showed high rates of bone union and survival. In mid-to long-term follow-up, the cortical strut allograft length did not affect to incorporation time. The author concluded that cortical strut allografts are useful treatment for PFFs regardless subtype classification of the Vancouver type B.

Use of a Constrained Acetabular Liner to Prevent and Treat Recurrent Dislocation after Total Hip Replacement Arthroplasty.

The aim of the present study was to evaluate the dislocation rate and the risk factors leading to instability after primary and revision total hip replacement arthroplasty (THRA) with constrained acetabular liners (CAL), as well as treatment strategies for prevention of dislocation. From 1999 to 2017, drawing on two institutions' THRA registries, we retrospectively identified 46 THRA cases using a CAL that had been followed up for a minimum of 4 years. The patients comprised 39 women and 7 men, with an average age of 69.1 years (age range, 41-98). Of the 46 patients, CAL were used in 12 patients for prevention of dislocation in primary THRA and in 34 patients for treatment of recurrent dislocation after primary THRA. Clinical and radiological evaluation were performed. We evaluated the failure rate of CAL as well as the risk factors. The 12 patients who used CAL for prevention of dislocation in primary THRA had no dislocation. However, 12 (35%) of the 34 hips had a dislocation after use of CAL in revision THRA. Patients with an abductor muscle weakness grade of ≤3 had a higher rate of dislocation than those with a grade of ≥4 (grade 1; likelihood ratio = ∞, grade 2; likelihood ratio = 1.83, grade 3; likelihood ratio = 1.05, grade 4; likelihood ratio = 0.46, and grade 5; likelihood ratio = 0). The group of primary THRA with CAL had no dislocations, and this is a proper way for prevention of dislocation in high-risk patients. The group of revision THRA with CAL had a high dislocation rate (35%). Abductor muscle weakness below grade 3 was a risk factor for failure of CAL for hip dislocation. We recommend treating patients with recurrent dislocations with the presence of abductor muscle weakness below grade 3 with not only THRA using CAL but also applying additional abductor muscle reconstruction to reduce the risk of dislocation.

Effect of Osteosarcopenia on Postoperative Functional Outcomes and Subsequent Fracture in Elderly Hip Fracture Patients.

INTRODUCTION: In this study, we evaluated how muscle mass and bone density affect postoperative functional scores and subsequent fracture rates and investigated the correlation between sarcopenia and osteoporosis by measuring preoperative psoas muscle indices (PMIs) and bone mineral densities (BMDs) in elderly patients followed for more 1 year after surgical treatment for hip fracture. METHODS: Among patients older than 65 years who underwent surgery for hip fracture from January 2009 to November 2018, 154 patients with preoperative 3D pelvic bone computed tomography and dual-energy X-ray absorptiometry BMD data and followed postoperatively for at least 1 year were considered for the present study. One hundred twenty-six patients were finally included. These patients were divided into 4 groups based on PMIs and T-score, that is, to osteoporosis, sarcopenia, osteosarcopenia, or normal groups. To analyze outcomes after surgery, we measured functional activity levels using the Barthel index and Harris hip score (HHS) systems. In addition, we compared the rates of subsequent hip fracture ratio with patient's characteristics, and analyzed the correlation between PMIs and BMDs using Pearson correlations analysis. RESULTS: Barthel index and HHS score showed significant differences between the normal and osteosarcopenia group at 6 weeks, 3 months, and 1 year after surgery (P < .001). Subsequent fracture incidences were significantly higher in the osteosarcopenia group than in the normal group (P = .046), and T-score and PMI were found to be strongly correlated (a < 0.01; R = 0.763). CONCLUSION: Postoperative functional outcomes were significantly poorer and the subsequent fracture rate was significantly higher in the osteosarcopenia group than in the normal group. In addition, sarcopenia and osteoporosis were found to be highly correlated.

Factors associated with postoperative acute kidney injury after hip fractures in elderly patients.

OBJECTIVES: Acute kidney injury (AKI) is a rare but serious complication after hip fractures. The aim of this study was to evaluate the incidence and the risk factors of postoperative AKI after hip fractures. METHODS: From January 2011 to December 2016, 550 patients who underwent surgery of hip fractures at our institution were retrospectively reviewed. AKI was defined and classified by AKI Network (AKIN) Classification/Staging System. The incidence, mortality, and risk factors of postoperative AKI were investigated. Receiver operating characteristic curve analysis was conducted to evaluate the ability of markers in predicting AKI. RESULTS: The incidence of postoperative AKI was 4.4% (25 cases). The mean onset of postoperative AKI was 8.0 ± 5.3 days and recovered after 7.0 ± 4.2 days after the occurrence of AKI. Of 25 patients with AKI, 6 patients (24.0%) died within 1 year after surgery. The independent risk factors for postoperative AKI are the estimated blood loss (EBL) (odds ratio (OR) 1.64; 95% confidence interval (CI) 1.33-2.58; p < 0.01) and postoperative level of albumin (OR 1.77; 95% CI 1.52-2.74; p < 0.01). The cutoff value of the serum albumin was <2.8 g/dL with a sensitivity of 88.0% and a specificity of 77.1%. The cutoff value of EBL was <766.5 mL with a sensitivity of 84.0% and a specificity of 66.3%. CONCLUSION: Postoperative AKI after hip fractures had low incidences (4.4%) but high mortality (24.0%). The postoperative AKI was correlated with blood loss and low postoperative albumin levels.

Prediction Value of SPECT/CT in Avascular Necrosis of Femoral Head After Femur Neck Fracture.

INTRODUCTION: The aim of this study was to determine the diagnostic value of single-photon emission computed tomography/computed tomography (SPECT/CT) in prediction of avascular necrosis (AVN) after femoral neck fracture and to evaluate whether photon defect in femoral head as seen in SPECT/CT can be an index for choice of surgical method. METHODS: This study was based on 97 patients who took SPECT/CT after femoral neck fracture from November 2012 to November 2017, with 64 patients with femoral intertrochanteric fracture in which chances of AVN is rare as a comparison group. Among 97 patients with femoral neck fracture, osteosynthesis was conducted in 7 patients with less than 15% of photon defect in damaged femoral head and 7 patients who wanted osteosynthesis, despite photon defect more than 15%, and 83 patients with photon defect more than 25% had arthroplasty. Patient with osteosynthesis was followed up with AVN by conducting magnetic resonance imaging (MRI) in 1 year after the surgery. RESULTS: Quantitative analysis of SPECT/CT in 14 patients who had femoral neck osteosynthesis showed that 7 patients with femoral neck fracture showed photon defect of 15% or more, but less than 25% and 3 patients in these were diagnosed with AVN after 1-year follow-up by MRI. Sensitivity and specificity of SPECT/CT in predicting AVN was 100% and 63.6%, respectively, with prediction accuracy of 71.4%. Among 14 patients with femoral neck fracture who had osteosynthesis, photon defect in 3 patients diagnosed with AVN was 19.6% ± 5.2%, but photon defect in 11 patients who was not diagnosed with AVN was 10.7% ± 5.2%, showing statistically significant difference between 2 groups (P = .001). CONCLUSION: Single-photon emission computed tomography/CT in patients with femoral neck fracture is considered to have diagnostic value in predicting occurrence of AVN, and percentage of photon defect is considered to be an useful index in determining the operative method.

Is the Oral Chemical Prophylaxis Necessary for the Prevention of Venous Thromboembolism after Joint Arthroplasty in a Korean Population?

PURPOSE: Venous thromboembolism (VTE) is a serious complication that may occur after a major orthopedic surgery. The aim of the present study was to determine the necessity of a chemical thromboprophylactic agent (rivaroxaban [RXB]) by analyzing the prevalence of VTE in Korean arthroplasty patients who received RXB for prophylaxis compared with those who did not receive RXB. MATERIALS AND METHODS: A total of 2,603 patients who underwent knee or hip arthroplasty between 1996 and 2017 were prospectively evaluated. Of these, 1,608 patients underwent surgery before January 2010 and were not administered any type of prophylaxis after surgery; the remaining 995 underwent surgery after 2010 and received oral RXB once daily for 5-13 days from the day after hemovac drain removal to postoperative day 14. RESULTS: The primary study outcome was the prevalence of VTE, pulmonary embolism or death during follow up. The overall incidence of VTE was 1.69% (n=44); of these, 12 occurred in the RXB group and 32 in the non-prophylactic group. The odds ratio of VTE in the RXB group was 0.61. However, the statistical power of the study was 0.313 due to the low incidence of VTE. CONCLUSION: Treatment with oral chemical prophylaxis decreased the incidence of VTE after knee or hip arthroplasty in a Korean population. Furthermore, no serious complications occurred after administering oral RXB, which, coupled with its convenience, suggests oral RXB offers an attractive alternative to other agents. However, we recommend that further studies, including a multicenter study, be conducted to achieve adequate statistical power.

Prognostic Factors and Clinical Outcomes after Treatment of Periprosthetic Femoral Fractures Using a Cable-plate.

PURPOSE: To analyze prognostic factors for the treatment of periprosthetic femoral fractures (PFFs) using the cable-plate construct. MATERIALS AND METHODS: A retrospective review of a consecutive series of 41 PFFs treated by osteosynthesis using the cable-plate system. The mean age of patients was 67.3±12.1 years (range, 42-86 years) and the mean follow-up period was 31.5±11.6 months (range, 12-58 months). Fresh frozen cortical strut allografts were leveraged in three cases for additional stability. Prognostic factors that may potentially affect clinical outcomes were analyzed. RESULTS: At the time of final follow-up, fracture union was obtained in 29 hips (70.7%; Group I) after an average of 13.5 weeks (range, 12-24 weeks). Healing failure after surgical treatment was observed in 12 cases (29.3%; Group II), including delayed union (n=10) cases and nonunion (n=2). Factors significantly associated with fracture union included fracture pattern (P=0.040), plate overlap percentage to stem length (P<0.001) and T-score at the preoperative bone mineral density (P=0.011). Transverse-type fractures around or just distal to a well-fixed femoral stem were observed in six cases (50.0%) of Group II. CONCLUSION: The cable-plate osteosynthesis of PFFs should be performed with caution in transverse-type fractures or in cases with severe osteoporosis. Fixation with sufficient plate overlap to stem length may be critical to prevent healing failure.

Long-Term Results of Hip Arthroplasty Using Extensive Porous-Coated Stem-A Minimum Follow-Up of 15 Years.

INTRODUCTION: We report the clinical and radiographic results of hip arthroplasty using extensive porous-coated stems over 15 years in Korea. METHODS: This retrospective study included 210 patients (268 hips) who underwent total hip arthroplasties (232 hips) and bipolar hemiarthroplasties (36 hips) between June 1996 and December 2002 for avascular necrosis of the femoral head, hip fracture, or osteoarthritis, after excluding those who died or were lost to follow-up. One senior author (K.H.M.) evaluated Harris Hip Score (HHS); limping gait; and leg length discrepancy, and 3 independent reviewers assessed the radiographic findings, including the level of stress shielding, Dorr classification, subsidence and loosening of femoral stem, heterotopic ossification (Brooker classification), osteolysis of acetabulum, wear rate of the polyethylene liner, component loosening, and revision rate. RESULTS: The mean follow-up duration was 16.9 years and average age at operation was 50.9 years. The HHS improved at the last follow-up. Stress shielding was grade 1 in 185 hips, grade 2 in 35 hips, grade 3 in 37 hips, and grade 4 in 11 hips. Femoral stem subsidence was <3 mm in 4 hips and >3 mm in 6 hips. Femoral stems with stable bony ingrowth were observed in 258 hips, fibrous stable femoral stems in 4 hips, and unstable femoral stems in 6 hips. Heterotopic ossification was class 1 in12 and class 2 in 4 hips. Revision surgery was performed for periprosthetic osteolysis of cup (45 hips), recurrent dislocation (1), unstable femoral stem (1), and infection (1). The Kaplan-Meier survivorship at the 15-year follow-up was 86.2%. The survivorship of femoral stem at 15 years was 99.3%, and if including impending revision due to unstable femoral stem was 97.1%. DISSCUSSION: This study has all the limitations inherent with a retrospective design. However, a large number of patients in this cohort operated on by a single surgeon and a long-term follow-up are some of the potential advantages of the current study. CONCLUSIONS: At the 15-year follow-up, extensive porous-coated stem showed relatively good survivorship even in geriatric patients (Dorr type C).

Clinical efficiency of bone marrow mesenchymal stem cell implantation for osteonecrosis of the femoral head: a matched pair control study with simple core decompression.

BACKGROUND: To date, several trials have reported the use of mesenchymal stem cell (MSC) implantation for osteonecrosis of the femoral head (ONFH). However, the clinical outcomes have not been conclusive. This study compared the clinical and radiological results of bone marrow mesenchymal stem cell (BMMSC) implantation with traditional simple core decompression (CD) using a matched pair case-control design. METHODS: We retrospectively reviewed 100 patients with ONFH (106 hips) who had been treated by CD alone (50 patients, 53 hips) and CD + BMMSC implantation (50 patients, 53 hips) between February 2004 and October 2014. We assessed the total hip replacement arthroplasty (THA) conversion rate and ARCO (Association Research Circulation Osseous) stage progression. Survivor rate analysis was performed using the Kaplan-Meier method, and an additional THA was defined as the primary endpoints. RESULTS: The mean follow-up period was 4.28 years. There was a difference in the THA conversion rate between the CD (49%) and CD + BMMSC groups (28.3%) (p = 0.028). ARCO stage progression was noted in 20 of 53 hips (37.7%) in the CD group and 19 of 53 hips (35.8%) in the CD + BMMSC group. Among collapsed cases (ARCO stages III and IV), there was no difference in clinical failure rate between the two groups. Conversely, in the pre-collapse cases (ARCO stages I and II), only 6 of 30 hips (20%) progressed to clinical failure in the CD + BMMSC group, whereas 15 of 30 hips (50%) progressed to clinical failure in the CD group (p = 0.014). Kaplan-Meier survival analysis showed a significant difference in the time to failure between the two groups up to 10-year follow-up (log-rank test p = 0.031). There was no significant difference in terms of age (p = 0.87) and gender (p = 0.51) when comparing THA conversion rates between groups. No complication was noted. CONCLUSIONS: These results suggest that implantation of MSCs into the femoral head at an early stage of ONFH lowers the THA conversion rate. However, ARCO stage progression is not affected by this treatment. TRIAL REGISTRATION: Retrospectively registered.

Cementless total hip arthroplasty in young patients under the age of 30: a minimum 10-year follow-up.

PURPOSE: The purpose of this study was to evaluate the clinical and radiologic outcomes of young patients (under the age of 30) who received a total hip arthroplasty (THA) and in whom patients had been followed for more than 10 years. MATERIALS AND METHODS: This retrospective study was conducted for 51 hips (44 patients) that had undergone THA. The mean age for the index operation was 25.71 years, and the mean follow-up period was 13.7 years. Clinical outcomes were evaluated by Harris hip score (HHS), activity level, and complications. Radiographic evaluations were assessed according to osteolysis, loosening, and polyethylene wear. RESULTS: The average HHS improved from 67.47 pre-operatively to 97.42 at the final follow-up ( p < 0.001). The activity level changed from 1.92 pre-operatively to 1.33 at the final follow-up ( p < 0.001). Ten cases had undergone revision arthroplasty within the follow-up period, and the overall survival rate was 80.4% at the final follow-up with revision for any reason as the end point. Polyethylene liners were used in all revision cases ( p = 0.003). Patients with modular stem had a higher failure rate than patients with a fully porous coated stem ( p < 0.001). Furthermore, a small diameter head size was associated with a higher risk of revision surgery ( p = 0.003). Complications such as dislocations were found in three hips. CONCLUSION: Cementless THA yields encouraging clinical and radiological results in young and active patients under the age of 30. However, the bearing surface, type of stem, and head size influenced component durability and revision rate.

Medium- to Long-term Results of Strut Allografts Treating Periprosthetic Bone Defects.

PURPOSE: We evaluated the medium- to long-term outcomes of cortical strut allografts used to treat periprosthetic bone defects to better understand the correlation between radiological and clinical outcomes. MATERIALS AND METHODS: We retrospectively reviewed outcomes from 19 patients undergoing cortical strut allografts to treat periproshtetic bone defects from 2001 to 2015. The mean age at index operation was 59.4 years and the average follow-up period was 8.6 years. Surgeries were performed because of aseptic loosening (n=9), periprosthetic fractures (n=5), and infections (n=5). Each case was characterized and described in detail including the length of allograft and the union period; possible correlations between allograft length and detailed classification and union period was analyzed. Clinical evaluations included the Harris hip score and Kaplan-Meier survivorship. RESULTS: In revision total hip arthroplasty (THA), the average length of allografts used in patients experiencing fractures was significantly longer than those with aseptic loosening or infection. Of the 19 cases, incorporation was observed in 18 cases (94.7%). The average time to incorporation was 21.2 months and the time to incorporation was not significantly different among the two groups (fracture vs. aseptic loosening or infection). No positive correlation was identified between the length of allograft and incorporation period or in the time to cortical strut allograft incorporation among Paprosky or Vancouver subgroups. CONCLUSION: Results of cortical strut allografts show excellent incorporation rates based on medium- to long-term follow-up. Cortical strut allografts may be considered useful for the treatment of femoral bone defects experienced during revision THA and following periprosthetic fracture.

Long-term clinical outcome of two-stage revision surgery for infected hip arthroplasty using cement spacer: Culture negative versus culture positive.

INTRODUCTION: Periprosthetic joint infection (PJI) is a terrible complication after hip arthroplasty. Clinical feature of culture-negative PJI (CN-PJI) has not been well studied till now. In our study, we retrospectively analyzed long-term clinical results after two-stage revision arthroplasty using an antibiotic-impregnated cement spacer for CN-PJI. The purpose of this study is to investigate the clinical features and prognosis of CN-PJI after hip arthroplasty and to compare these with those of culture-positive PJI (CP-PJI). METHODS: We retrospectively reviewed 15 CN-PJI cases and 70 CP-PJI cases following hip arthroplasty. The average follow-up period was 7.4 years (5-11.7 years). The demographics, laboratory findings, the time interval between antibiotic-impregnated cement spacer insertion and revision arthroplasty, and recurrence of infection were analyzed. RESULTS: The CN-PJI group showed a significantly higher incidence of prior antibiotic use ( p = 0.004) and lower serum C-reactive protein (CRP) level ( p = 0.001) than the CP-PJI group. Normalized time interval of CRP level in CN-PJI was shorter than that of CP-PJI group. The mean interval time for two-stage exchange arthroplasty was also significantly lower ( p = 0.049) in the CN-PJI group than the CP-PJI group. There was no case of treatment failure or major complication in CN-PJI group. CONCLUSION: The CN-PJI group after total hip arthroplasty could be treated successfully by two-stage exchange arthroplasty without any complications. Clinical course and prognosis of CN-PJI group was also better compared with that of CP-PJI group. Therefore, culture negativity of PJI cannot be always a poor prognostic factor for the treatment.

Primary Total Hip Arthroplasty Using Summit® Stems in Korean: Minimum Four-year Follow-up.

PURPOSE: The aim of this study was to assess the mid-term results of primary cementless total hip arthroplasty (THA) using Summit® stems. MATERIALS AND METHODS: One hundred twenty-eight arthroplasties in 121 patients who were performed THA from December 2004 to March 2013, were reviewed retrospectively a minimum of 4 years follow-up (mean age, 60.3 years; mean postoperative follow up period, 86.3 months). For a clinical evaluation, the Harris hip score (HHS) was used to assess outcome. Radiographic evaluation was done through spot welds, subsidence, stress shielding, canal filling. RESULTS: The mean HHS was 69.8 points preoperatively, and it improved significantly to 96.3 points at the final follow-up. Postoperatively, 10 patients experienced thigh pain and 7 patients showed a moderate limping gait. There was not only early stem subsidence but there was no more subsidence at last follow up. One hundred eighteen hips showed radiographic signs of stem bone ingrowth, and 10 hips showed fibrous ingrowth at the last follow-up. Stress shielding occurred in 85 hips and third degree stress shielding was observed in 6 hips. Complication arose in 10 hips due to dislocation. Although revisions due to recurrent dislocations led to acetabular component revision in one hip, no revisions arose due to isolated aseptic loosening of the femoral component. CONCLUSION: The clinical and radiological mid-term results of primary THA using Summit® stems revealed solid initial fixation and bone ingrowth stable fixation. Considering the satisfactory clinical results, Summit® stems may be a good treatment option in Korean patients who were required hip arthroplasty.

Topical administration of tranexamic acid in hip arthroplasty.

PURPOSE: The purpose of this study was to assess the efficacy of a newly designed topical administration of tranexamic acid (TXA) in reducing post-operative bleeding in total hip arthroplasty (THA) and bipolar hip hemiarthroplasty (BHA). METHODS: A consecutive series of 160 patients who underwent hip arthroplasty was enrolled in this study. Topical administration of TXA was done in group 1 (40 patients underwent THA and 40 BHA). We compared the amount of blood loss and rates of post-operative transfusion in group 1 with those of group 2 (40 cases of THA and 40 cases of BHA) in which TXA solution was not applied. RESULTS: The total amount of blood loss in THA group 1 and THA group 2 was 793 ± 50 mL and 1086 ± 73 mL, respectively (p = 0.001). The transfusion rates of THA group 1 and THA group 2 was 27.5 % and 50 %, respectively (p = 0.039). The transfusion rates of BHA group 1 and BHA group 2 was 45 % and 60 %, respectively (p = 0.179). The amounts of blood loss through the drainage tube were 186 ± 22 mL and 257 ± 24 mL in THA group 1 and THA group 2, respectively, and 101 ± 11 mL and 147 ± 16 mL in BHA group 1 and BHA group 2, respectively, showing statistical significance. No complications such as infection, deep vein thrombosis or cardiovascular disease were observed during the hospital stay and the last follow-up. CONCLUSION: Topical administration of TXA is an effective and safe method to reduce post-operative bleeding and transfusion rates in hip arthroplasty.

Clinical Results of Internal Fixation of Subcapital Femoral Neck Fractures.

BACKGROUND: Subcapital femoral neck is known to cause many complications, such as avascular necrosis (AVN) of the femoral head or nonunion, compared with other femoral neck fractures. The purpose of this study was to analyze the incidence of AVN and fixation failures in patients treated with internal fixation using cannulated screws for the subcapital femoral neck fractures. METHODS: This study targeted a total of 84 cases of subcapital femoral neck fractures that underwent internal fixation using cannulated screws. The average follow-up time after surgery was 36.8 months (range, 24 to 148 months). RESULTS: Nine hips (10.7%) showing AVN of the femoral head and 6 hips (7.1%) showing fixation failures were observed. The factors affecting the incidence of AVN of the femoral head after sustaining fractures correlated well with fracture types in the Garden classification (p = 0.030). The factors affecting fixation failure were the degree of reduction (p = 0.001) measured by the Garden alignment index and firm fixation (p = 0.009) assessed using the technique of 3-point fixation through the inferomedial cortical bone of the femoral neck. CONCLUSIONS: The complication rates for subcapital femoral neck fractures were lower than those previously reported; hence, internal fixation could be a primary treatment option for these fractures.

Bilateral Idiopathic Chondrolysis of the Hip in an Adult: A Case Report and Review of the Literature.

Idiopathic chondrolysis of the hip usually develops in adolescents and is a disease characterized by gradual degenerative changes of the hyaline cartilage surrounding the head of the femur. It eventually decreases the hip joint space and causes limitations in the hip joint range of motion due to pain. The authors had experienced an unusual case of bilateral idiopathic chondrolysis of the hip in an 54 year-old male; thus, we report the treatment results and literature reviews in this case report.

Clinical features of atypical femur fracture.

OBJECTIVES: We aim to elucidate the clinical outcomes of bisphosphonate-associated atypical femoral fracture and the clinical results depending on the bisphosphonate therapy period. METHODS: Twenty cases involving 15 patients who had been diagnosed with atypical femoral facture between 2004 and 2014 and who had been followed up for at least 12 months were retrospectively analyzed. The control group was composed of 15 typical femoral facture patients. We used plain radiography and physical examinations to determine the period of time required for fracture healing as well as complication occurrence. We investigated the bisphosphonate administration status and duration and the names of its components, bilateral fracture occurrence status, the period of time required for bone union, and reoperation or bone graft status due to nonunion. RESULTS: Revision surgery involving a bone graft was performed due to nonunion in 1 out of 15 cases. Except in one revision case, the duration of the union was 11.9 months on average in 14 cases of atypical fracture patients, and 4.3 months on average in the control group. This difference was statistically significant (p < 0.05). The bisphosphonate administration duration was positively correlated with the union period (p < 0.05). In contrast, there was no statistically significant correlation between the bisphosphonate administration duration and the incidence of bilateral atypical fractures (p > 0.05). CONCLUSIONS: Atypical femoral fractures required more time for bone union than typical ones and prolonged bisphosphonate administration led to a longer period of time required for bone union.

Total knee replacement arthroplasty with Buechel and Pappas knee: minimum 2-year follow-up.

BACKGROUND: Clinical and radiologic evaluation and analyses of the surgeries using Buechel and Pappas (B-P) knee implants. METHODS: The study was conducted on 60 patients who underwent 94 total knee replacement arthroplasty with B-P knee implants from May 2009 to December 2010. The results were compared to the results of 41 patients who underwent 60 knee joint surgeries using NexGen-LPS implants from January 2008 to August 2009. RESULTS: The American Knee Society score of the B-P knee group increased from an average of 66.9 (clinical score) and 65.5 (functional score) to 93.4 and 90.3, respectively; while those for the NexGen-LPS group increased from an average of 68.8 (clinical score) and 62.4 (functional score) to 86.3 and 76, respectively. The average ranges of motion of the B-P knee group and the NexGen-LPS group were 119.1° and 114.8°, respectively, before surgery and improved to 121.0° and 123.0° at final follow-up after the surgery. The visual analogue scale scores for the B-P knee group and the NexGen-LPS group improved from 4.7 and 4.6 to 1.4 and 1.8, respectively. The flexion contracture also improved from 5.1° and 6.3° to 0.64° and 1.72°. The tibio-femoral angle for the B-P knee group and the NexGen-LPS group also improved greatly after the surgery, from varus 0.34° and 0.73° each to valgus 6.7° and 6.9°, respectively. CONCLUSIONS: The evaluation of more than 2 years of total knee replacement arthroplasty using B-P knee implants showed good results. B-P knee implants showed a relatively higher degree of satisfaction in clinical knee score and less intraoperative bone mass removal than NexGen-LPS implants.

The Usefulness of Three-dimensional Computed Tomography as an Assessment of Periacetabular Osteolysis in Revision Total Hip Arthroplasty.

PURPOSE: This study was performed to determine the usefulness of three-dimensional computed tomography (3D-CT) in measuring periacetabular osteolysis by comparing the real volume of osteolysis in revision surgery. MATERIALS AND METHODS: Twnety-three patients who had undergone revision surgery due to periacetabular osteolysis but not included septic osteolysis and implant loosening. The mean age of patients at the time of surgery was 55.2 years. And the mean time interval between the primary total hip arthroplasty and revision surgery was 13.3 years. We measured the polyethylene wear in plain radiographs using computer assisted vector wear analysis program, the volume of acetabular osteolytic lesions in high-resolution spiral CT scans using Rapidia 3D software version 2.8 algorithms before the revision surgery were performed. Intraoperative real osteolytic volume was calculated as the sum of the volumetric increments of the acetabular cup and impacted allo-cancellous bone volume. RESULTS: Strong correlation was found between the volume of acetabular osteolytic lesions measured on 3D-CT and intraoperative real osteolytic volume which was calculated as the sum of the volumetric increments of the acetabular cup and impacted allo-cancellous bone volume. CONCLUSION: 3D-CT is considered a useful method for assessing and measuring the volume of periacetabular osteolysis before revision surgery.

Cementless Revision Total Hip Arthroplasty with Ceramic Articulation.

PURPOSE: The results of ceramic-on-ceramic (CoC) bearing surfaces in primary total hip arthroplasty (THA) were well known. However, it was not known in revision THA. The purpose of this study is to report the results of revision THA with ceramic articulation. MATERIALS AND METHODS: A total of 112 revision THAs were evaluated. The mean age at the time of surgery was 51.6 years (27.7 to 84.2 years). The mean duration of the follow-up periods was 6.3 years (2.3 to 11.4 years). RESULTS: The Harris hip scores improved from an average of 56.2 at the index surgery to an average of 93.3 at the last follow-up (P<0.001). None of hips showed osteolysis or ceramic head fracture. One hip showed aseptic loosening in the acetabular component with squeaking that caused a re-revision. There were nine cases of dislocation. The survivorship at 5 years was 94.5% (95% confidence interval, 87.9% to 97.6%) with revision for any reason as the endpoint and 100% with femoral revision. CONCLUSION: The ceramic articulation is one of good bearing options for revision THA in patients with a long life expectancy.