Shang-Wen Tsai

Etiologies and outcome of osteonecrosis of the femoral head: Etiology and outcome study in a Taiwan population

Background Osteonecrosis of the femoral head (ONFH) is an important indication for total hip arthroplasty in Taiwan. We demonstrated the etiologies of ONFH and outcomes based on stratification of patients according to different etiologies. Methods We reviewed medical records and images from January 2000 to May 2010 in our database with the diagnosis of “osteonecrosis of the femoral head.” We categorized all patients into different etiologies, including corticosteroid, alcohol, and idiopathic. All patients received subsequent follow up for ipsilateral precollapse ONFH and contralateral disease‐free femoral head status after initial diagnosis. Results Of the 1153 patients who had undergone 1674 hip surgeries including core decompression and total hip replacement, alcohol use was the most prevalent etiology in our population (45.2%). Patients with corticosteroid‐ and alcohol‐associated ONFH were younger and more likely to have bilateral disease. Patients with alcohol‐ or steroid‐associated ONFH were found to have a higher rate of contralateral disease and faster progression of precollapse ONFH than patients who had or had not undergone core decompression. Conclusion Alcohol use had the greatest impact on ONFH in our population. Nonidiopathic ONFH patients had the worst outcome. Understanding the nature of progression of ONFH and incidence of contralateral disease may provide great prognostic value to detect and perform early intervention.

Does Implant Selection Impact Postoperative Complications Following Hip Arthroplasty for Failed Intertrochanteric Fractures? A Retrospective Comparative Study

The purpose of this study is to compare postoperative complications among different acetabular and femoral components of hip arthroplasty for failed intertrochanteric fractures. A total of 79 patients were included and followed-up for an average of 75.6 months (range, 24-244). Fifty-five patients underwent total hip arthroplasty, and 24 had bipolar hemiarthroplasty. Cementless metaphyseal locking, cementless diaphyseal locking, and cemented standard stems were used in 41, 29, and 9 patients, respectively. Dislocation and wear rate were not different between the total hip arthroplasty and bipolar hemiarthroplasty groups. Stem subsidence or loosening was more frequently found in the cementless, metaphyseal locking stem groups. In conclusion, cemented standard stem and cementless diaphyseal locking stem might be better implant choices. With regard to dislocation rate, our results were insufficient to conclude a better implant choice of total hip arthroplasty or bipolar hemiarthroplasty than the other.

Prognosis-Based Shoulder Hemiarthroplasty After Resection of Proximal Humeral Malignancy

After wide excision of proximal humeral bony malignancy, prognosis-based reconstruction was performed at Taipei Veterans General Hospital. Bone prosthesis composite (BPC) was carried out among patients with a favored prognosis, while cement-spacer prosthesis composite (CSPC) was preserved for patients with poor prognosis. The aim of our study is to compare the clinical outcomes between the BPC and CSPC reconstruction procedures. From January 2000 to December 2014, we retrospectively reviewed the clinical outcomes of 34 patients who underwent shoulder hemiarthroplasty following wide excision of a malignant lesion of the proximal humerus, 15 of whom were treated with a BPC reconstruction and 19 cases were treated with a CSPC reconstruction. The mean postoperative follow-up was 51.9 months for the BPC group and 29.0 months for the CSPC group. At the end of the study, four patients (two in the BPC group and two in the CSPC group) developed local recurrence. Thirteen patients (1 in the BPC group and 12 in the CSPC group) had died of disease progression. The postoperative visual analogue scale score of BPC and CSPC groups was similar (P = 0.262). Functional outcome, measured using the Musculoskeletal Tumor Society score and shoulder range of motion, favored the BPC procedure (P < 0.001). The CSPC procedure, however, had less complication rate, required less operative time, and had a lower volume of intraoperative blood loss than the BPC procedure (P < 0.001). Although functional outcomes are expected to be more favorable with a BPC procedure, the CSPC procedure continues to be a safe and cost-effective shoulder hemiarthroplasty procedure for patients with low-demanding activities and when a poor disease prognosis is expected.

Optimal timing for elective total hip replacement in HIV-positive patients

INTRODUCTION Evidence about the optimal timing for total hip replacement (THR) in HIV-positive patients is scant. HYPOTHESIS Preoperative criteria: cluster of differentiation 4 (CD4) counts>200cells/mm3 and an undetectable HIV virus load before THR, improve infection rates, aseptic loosenings, and functional outcomes. MATERIALS AND METHODS We recruited 16 HIV-positive patients who had undergone 25 THRs between 2003 and 2015. None had hemophilia, and none were intravenous drug users (IVDUs). RESULTS Their mean age was 41.2 years (range: 24-60); minimum follow-up was 12 months (mean: 64.6); mean duration of prophylactic antibiotics was 2.9 days (range: 1-5); and mean hospital length of stay was 6.0 days (range: 4-11). No patients were treated with subsequent oral antibiotics. The mean preoperative CD4 count was 464.1±237.0 (range: 235-904)cells/mm3. There were no early superficial surgical site infections, late periprosthetic joint infections, or aseptic loosenings. Post-surgery Harris Hip score was significantly (p<0.001) better. DISCUSSION A preoperative CD4 count>200cell/mm3 and an undetectable HIV virus load might indicate optimal timing for elective THRs in HIV-positive patients without hemophilia and not IVDUs. LEVEL OF EVIDENCE IV, retrospective or historical series.

Cement augmentation in the proximal femur to prevent stem subsidence in revision hip arthroplasty with Paprosky type II/IIIa defects

Background: Subsidence remains a common complication after revision hip arthroplasty which may lead to prolonged weight‐bearing restrictions, leg‐length discrepancies or considerable loss of function. We evaluated the effectiveness of cement augmentation in the proximal femoral metaphysis during a revision of femoral components to prevent post‐operative stem subsidence. Methods: Forty patients were enrolled. Follow‐up averaged 67.7 months (range: 24–149). Twenty‐seven patients had a Paprosky type II defect and 13 had a type IIIa defect. All revision hip arthroplasty used a cementless, cylindrical, non‐modular cobalt–chromium stem. The defect in the metaphysis was filled with antibiotic‐loaded bone cement. Thirteen patients who had undergone stem revision only was allowed to walk immediately without weight‐bearing restrictions. Twenty‐seven patients who had undergone revision total hip arthroplasty was allowed partial weight‐bearing within 6 weeks after surgery in the consideration of acetabular reconstruction. Results: Three patients (7.5%) had post‐surgery stem subsidences of three mm, five mm, and 10 mm, respectively, at three, one, and 14 months. There were no acute surgical site infections. There were three femoral stem failures: two delayed infections and one periprosthetic Vancouver B2 fracture. Both five‐ and 10‐year survivorships of the femoral implant were 90.1%. Conclusion: An adequate length of the scratch‐fit segment and diaphyseal ingrowth remain of paramount importance when revising femoral components. To fill metaphyseal bone defects with antibiotic‐loaded bone cement may be an alternative method in dealing with proximal femoral bone loss during a femoral revision.

Grafting for bone defects after curettage of benign bone tumor – Analysis of factors influencing the bone healing

Background: Simple bone cyst often weaken bone properties and predispose to pathological fractures, requiring tumor excision and the filling of bone defects with grafts to prevent complications. The purpose of this study was to evaluate factors potentially affecting the quality and efficiency of graft healing. Methods: This study retrospectively assessed 84 patients with simple bone cysts who had undergone tumor excision and filling of the bone defects with grafts between 2004 and 2014. Various patient‐, tumor‐ and treatment‐related factors that could potentially influence radiologic healing status and time to stable healing were evaluated. Results: Bone healing was not related to gender and age. Graft type was not significantly correlated with both radiologic healing status or time to stable healing. Only two of all variables evaluated were significantly correlated with the prognosis: (1) Tumors location: patients with tumors located at proximal femur were significantly more likely to achieve complete healing (Neer I) (OR = 3.2; 95%CI, 1.29–8.00; p = 0.011). (2) Tumor length: patients with a tumor length less than 6.2 cm, complete healing was nearly five times more likely to occur (OR = 4.84; 95% CI, 1.83–12.84; p = 0.002). Degree of graft filling of the bone defects affected the time to stable healing. The average healing times were 4.86 months for filling degree ≥90% and 5.94 months for filling degrees <90%, respectively (p = 0.009). Postoperative re‐fracture occurred in one case. Conclusion: Factors influencing the quality of bone healing following intralesional curettage and bone grafting are proximal femur location and tumor length. A greater degree of graft filling can contribute to higher bone healing efficiency.

Does continued aspirin mono-therapy lead to a higher bleeding risk after total knee arthroplasty?

Background: Evidence about the risk of bleeding and thromboembolism because of aspirin mono-therapy in total knee arthroplasty (TKA) is scant. We wanted to validate the risks of bleeding and thromboembolism with continued aspirin mono-therapy in unilateral and simultaneous bilateral TKA. Methods: We enrolled a series of 1655 patients who underwent unilateral or simultaneous bilateral TKA between December 2010 and December 2012. Drainage amount, postoperative hemoglobin level, change in hemoglobin, calculated blood loss, incidence and the amount of blood transfused, and the proportion of thromboembolic events were compared between patients who were and patients who were not on continued aspirin mono-therapy. Results: Calculated blood loss (969.1 ± 324.9 vs. 904.0 ± 315.5 ml), transfusion amounts (1.3 ± 1.5 vs. 1.0 ± 1.3 IU), and percentage of transfused patients (53.0% vs. 40.2%) were higher in unilateral TKA patients on continued aspirin mono-therapy. Outcome parameters and the proportion of DVT between groups were not significantly different. One patient (0.3%) not on aspirin mono-therapy developed a pulmonary embolism, and two others (0.6%) had cerebrovascular events. Conclusion: Despite the slightly higher risks of bleeding, continuing aspirin mono-therapy during TKA might be safe with low risks of perioperative cerebrovascular, cardiovascular, and venous thromboembolic events.BACKGROUND Evidence about the risk of bleeding and thromboembolism because of aspirin mono-therapy in total knee arthroplasty (TKA) is scant. We wanted to validate the risks of bleeding and thromboembolism with continued aspirin mono-therapy in unilateral and simultaneous bilateral TKA. METHODS We enrolled a series of 1655 patients who underwent unilateral or simultaneous bilateral TKA between December 2010 and December 2012. Drainage amount, postoperative hemoglobin level, change in hemoglobin, calculated blood loss, incidence and the amount of blood transfused, and the proportion of thromboembolic events were compared between patients who were and patients who were not on continued aspirin mono-therapy. RESULTS Calculated blood loss (969.1 ± 324.9 vs. 904.0 ± 315.5 ml), transfusion amounts (1.3 ± 1.5 vs. 1.0 ± 1.3 IU), and percentage of transfused patients (53.0% vs. 40.2%) were higher in unilateral TKA patients on continued aspirin mono-therapy. Outcome parameters and the proportion of DVT between groups were not significantly different. One patient (0.3%) not on aspirin mono-therapy developed a pulmonary embolism, and two others (0.6%) had cerebrovascular events. CONCLUSION Despite the slightly higher risks of bleeding, continuing aspirin mono-therapy during TKA might be safe with low risks of perioperative cerebrovascular, cardiovascular, and venous thromboembolic events.

Alveolar soft part sarcoma: Clinical presentation, treatment, and outcome in a series of 13 patients

Background: Alveolar soft part sarcoma (ASPS) is a rare soft tissue tumor that typically affects young patients. Similar to other soft tissue sarcomas, it has high pulmonary metastasis ability, whereas compared with other soft tissue sarcomas, it has high brain metastasis ability. Because of the rarity of the disease, most studies on ASPS have been case reports and small series studies. Method: We performed a retrospective study to evaluate the clinical and pathological features and oncological results in a consecutive series of patients with localized or metastatic ASPS treated at our institute between 1994 and 2014. Demographics, location, severity of disease, treatment provided, progression‐free survival, and overall survival were evaluated. Results: A total of 13 patients were investigated. The most common locations of primary tumor were the thigh (n = 6, 47%), followed by the flank (n = 3, 23%), forearm (n = 2, 15%), and calf (n = 2, 15%). Three patients were initially diagnosed as having hemangiomas elsewhere. These patients received unplanned intralesional excision. All the patients received wide tumor resection at our institute. Over the average follow‐up period of 80.5 months (range: 36–133 months), the 5‐year overall survival rate was 67.5%. Four patients were continuously disease free (31%), six were living with disease (46%), and three died of disease (23%). Of nine patients who presented with distant pulmonary metastasis, two had bony and brain metastases. The 5‐year survival rate was 66.7% in patients who received chemotherapy and those who did not (p = 0.941). Conclusion: The treatment strategy for ASPS is wide resection, and postoperative chemotherapy may be crucial for long‐term survival. In addition, this type of tumor has a high distant metastasis rate at the time of diagnosis, particularly in the lungs and brain.

A safety comparative study between freezing nitrogen ethanol composite and liquid nitrogen for cryotherapy of musculoskeletal tumors

Freezing nitrogen ethanol composite (FNEC) showed effective cryoablative ability for bone tumor ex vivo and in vivo comparable to liquid nitrogen (LN). We therefore wished to compare the radiant cooling damage of the surrounding tissue between FNEC and LN. The evaluation of the radiant cooling damage was demonstrated human bone xenograft transplantation (HXT) in a mouse model. Characterizations and quantifications of the damaging effects on morphologic features and apoptosis of the cryoablative surrounding bone tissue, muscle and epidermal layer of skin were compared. The radiant cooled damaging effects including epidermal rupture, hair follicle atrophy, dermis and subcutaneous crystal vacuolation of skin were significantly greater in LN than FNEC. Muscular apoptosis, structural shrinkage and bone cellular apoptosis were supposedly 15%-33% destroying degrees of LN more than FNEC. We concluded that FNEC is an innovative cryogenic material, and it could cause less cryoablative damage to surrounding normal tissue than LN. The findings might support the safety of FNEC being applied in clinical cryoablation therapy.

Intraoperative Extracorporeal Irradiation and Frozen Treatment on Tumor-bearing Autografts Show Equivalent Outcomes for Biologic Reconstruction

Background Immediately recycling the resected bone segment in a biologic limb salvage reconstruction is an option after wide resection of bone. Intraoperative extracorporeal irradiation and freezing are the two major tumor-killing techniques applied on the fresh tumor-bearing autografts. However, graft-derived tumor recurrence and complications are concerns affecting graft survival. Questions/Purposes We therefore asked: (1) Is there a difference in the proportion of patients achieving union by 18 months after surgery between the groups with extracorporeal-irradiated autografts and frozen-treated autografts? (2) Is there any difference in the frequency of graft-related complications for patients receiving either an extracorporeal-irradiated or a frozen-treated autograft? (3) Is there a difference between the techniques in terms of graft-derived recurrence? (4) Are there differences in failure-free grafts, and limb and overall survivorship between autografts treated by extracorporeal irradiation or by freezing? Methods During the study period we treated a total of 333 patients with high-grade osteosarcoma. One hundred sixty-nine patients were excluded. Overall, 79 of the enrolled 164 patients received recycled autografts treated with extracorporeal irradiation whereas the other 85 received frozen-treated autografts. The mean followup was 82 ± 54 months for the extracorporeal irradiation group and 70 ± 25 months for the frozen autograft group, and one patient was lost to followup. Complications and graft failure (revision required for primary graft removal) were characterized by adapting the International Society of Limb Society (ISOLS) system modified for inclusion of biologic and expandable reconstruction. The primary study endpoints were the proportion of patients in each group who achieved radiographic union, and had an ISOLS grade of fair or good host graft fusion at 6, 9, 12, and 18 months after surgery. Five-year survival data for graft failure and limb amputation were analyzed by a cumulative incidence function regression model whereas the Kaplan-Meier function was used to test the 5-year overall survival rate between the two techniques. Results With the numbers available, no differences were found in the accumulated proportion of patients achieving union between the groups at 6, 9, 12, and 18 months. Radiographic evaluation did not show differences in the average scores of compared criteria. However in the subchondral bone subcriterion, more patients receiving frozen-treated autografts had higher scores (p = 0.03). Complications leading to a second surgery were not different between extracorporeal irradiation and frozen autografts in aspects of soft tissue failure (Type 1B), nonunion (Type 2B), structural failure (Type 3A and Type 3B), or infection (Type 4A and Type 4B). No graft-originating tumor recurrence was found and there was no difference in Type 5A tumor progression originating from soft tissue in the groups (odds ratio, 0.8; 95% CI, 0.3-2.1; p = 0.7). Neither group showed a difference in the cumulative incidence for graft failure and limb amputation. Five-year overall survival rates were 83% and 84% (p = 0.69) for extracorporeal-irradiated and frozen autografts respectively. A decrease in survivorship was seen at 50 to 100 months after surgery for the extracorporeal irradiation group. Conclusion We segregated the ISOLS criteria evaluating the graft-mediated tumor progression into host- or graft-derived complications (Types 5B and 5C) in this study. With the available data, there was no difference in the incidence of tumor recurrence derived from irradiation- or frozen-treated autografts. Ongoing evaluations comparing 10-year survivorship for both groups will be helpful to elucidate the possible difference found after 100 months. Level of Evidence Level III, therapeutic study