Radial head replacement with the 3D-printed patient-specific titanium prosthesis: Preliminary results of a multi-centric prospective study.

PURPOSE: To report preliminary clinical results and safety of 3D-printed patient-specific titanium radial head (RH) prosthesis in treatment of the irreparable RH fractures. MATERIAL AND METHODS: This multi-centric prospective study included 10 patients (6 men and four women, mean age 41 years (range, 25-64 years)). Three cases were classified as Mason type III and 7 cases as type IV. Patients were assessed preoperatively, intraoperatively, and at 1, 6, 12, 24, 36, and 48 weeks postoperatively. Range of motion (ROM), visual analog scale (VAS) score, Disabilities of the Arm, Shoulder and Hand (DASH) score, Mayo Elbow Performance Score (MEPS), radiology imaging, and laboratory blood and urine testing were evaluated. RESULTS: The prostheses were implanted utilizing cemented stems in 5 patients and cementless stems in 5 patients. Intraoperatively, well congruency of a prosthesis with capitellum and radial notch of ulna was observed in all cases. All patients had improvement of ROM, VAS score, DASH score, and MEPS during the postoperative follow-ups. At the final follow-up, mean elbow extension was 6.5° (range, 0°-30°), flexion 145° (range, 125°-150°), supination 79° (range, 70°-80°), and pronation 73.5° (range, 45°-80°). Mean VAS score was 0.3 (range, 0-3), DASH score was 12.35 (range, 1.7-23.3), and MEPS was 99.5 (range, 95-100). Postoperative radiographs demonstrated heterotopic ossification in 2 cases, periprosthetic radiolucency in 2 cases, and proximal radial neck resorption in 2 cases. No one had the evidence of capitellar erosion, implant failure, malpositioning, overstuffing, or symptomatic stem loosening. There was no significant alteration of laboratory results or adverse events related to the 3D-printed prosthesis implantation. CONCLUSION: The preliminary results demonstrated that implantation of the 3D-printed patient-specific titanium RH prosthesis is safe and may be a potential treatment option for irreparable RH fracture.

What Are the MSTS Scores and Complications Associated With the Use of Three-dimensional Printed, Custom-made Prostheses in Patients Who Had Resection of Tumors of the Hand and Foot?

BACKGROUND: There are a few good options for restoring bone defects in the hand and foot. 3D-printed implants have been used in the pelvis and elsewhere, but to our knowledge, they have not been evaluated in the hand and foot. The functional outcome, complications, and longevity of 3D-printed prostheses in small bones are not well known. QUESTIONS/PURPOSES: (1) What are the functional outcomes of patients with hand or foot tumors who were treated with tumor resection and reconstruction with a 3D-printed custom prosthesis? (2) What complications are associated with using these prostheses? (3) What is the 5-year Kaplan-Meier cumulative incidence of implant breakage and reoperation? METHODS: Between January 2017 and October 2020, we treated 276 patients who had tumors of the hands or feet. Of those, we considered as potentially eligible patients who might have extensive loss in their joint that could not be fixed with a bone graft, cement, or any prostheses available on the market. Based on this, 93 patients were eligible; a further 77 were excluded because they received nonoperative treatment such as chemoradiation, resection without reconstruction, reconstruction using other materials, or ray amputation; another three were lost before the minimum study follow-up of 2 years and two had incomplete datasets, leaving 11 for analysis in this retrospective study. There were seven women and four men. The median age was 29 years (range 11 to 71 years). There were five hand tumors and six tumors of the feet. Tumor types were giant cell tumor of bone (five), chondroblastoma (two), osteosarcoma (two), neuroendocrine tumor (one), and squamous cell carcinoma (one). Margin status after resection was ≥ 1 mm. All patients were followed for a minimum of 24 months. The median follow-up time was 47 months (range 25 to 67 months). Clinical data; function according to the Musculoskeletal Tumor Society, DASH, and American Orthopedic Foot and Ankle Society scores; complications; and survivorship of implants were recorded during follow-up in the clinic, or patients with complete charts and recorded data were interviewed on the telephone by our research associates, orthopaedic oncology fellows, or the surgeons who performed the surgery. The cumulative incidence of implant breakage and reoperation was assessed using a Kaplan-Meier analysis. RESULTS: The median Musculoskeletal Tumor Society score was 28 of 30 (range 21 to 30). Seven of 11 patients experienced postoperative complications, primarily including hyperextension deformity and joint stiffness (three patients), joint subluxation (two), aseptic loosening (one), broken stem (one), and broken plate (one), but no infection or local recurrence occurred. Subluxations of the metacarpophalangeal and proximal interphalangeal joints in two patients' hands were caused by the design of the prosthesis without a joint or stem. These prostheses were revised to a second-generation prosthesis with joint and stem, leading to improved dexterity. The cumulative incidence of implant breakage and reoperation in the Kaplan-Meier analysis was 35% (95% CI 6% to 69%) and 29% (95% CI 3% to 66%) at 5 years, respectively. CONCLUSION: These preliminary findings suggest that 3D implants may be an option for reconstruction after resections that leave large bone and joint defects in the hand and foot. Although the functional results generally appeared to be good to excellent, complications and reoperations were frequent; thus, we believe this approach could be considered when patients have few or no alternatives other than amputation. Future studies will need to compare this approach to bone grafting or bone cementation. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Exploring Usability Issues of a Smartphone-Based Physician-to-Physician Teleconsultation App in an Orthopedic Clinic: Mixed Methods Study.

BACKGROUND: Physician-to-physician teleconsultation has increasingly played an essential role in delivering optimum health care services, particularly in orthopedic practice. In this study, the usability of a smartphone app for teleconsultation among orthopedic specialists was investigated to explore issues informing further recommendations for improvement in the following iterations. OBJECTIVE: This study aimed to explore usability issues emerging from users' interactions with MEDIC app, a smartphone-based patient-centered physician-to-physician teleconsultation system. METHODS: Five attending physicians in the Department of Orthopedics in a large medical school in Bangkok, Thailand, were recruited and asked to perform 5 evaluation tasks, namely, group formation, patient registration, clinical data capturing, case record form creation, and teleconsultation. In addition, one expert user was recruited as the control participant. Think aloud was adopted while performing the tasks. Semistructured interviews were conducted after each task and prior to the exit. Quantitative and qualitative measures were used to identify usability issues in 7 domains based on the People At the Centre of Mobile Application Development model: effectiveness, efficiency, satisfaction, learnability, memorability, error, and cognitive load. RESULTS: Several measures indicate various aspects of usability of the app, including completion rates, time to completion, number of clicks, number of screens, errors, incidents where participants were unable to perform tasks, which had previously been completed, and perceived task difficulty. Major and critical usability issues based on participant feedback were rooted from the limitation of screen size and resolution. Errors in data input (eg, typing errors, miscalculation), action failures, and misinterpretation of data (ie, radiography) were the most critical and common issues found in this study. A few participants did not complete the assigned tasks mostly owing to the navigation design and misreading/misunderstanding icons. However, the novice users were quite positive that they would be able to become familiar with the app in a short period of time. CONCLUSIONS: The usability issues in physician-to-physician teleconsultation systems in smartphones, in general, are derived from the limitations of smartphones and their operating systems. Although some recommendations were devised to handle these usability issues, usability evaluation for additional development should still be further investigated.

Anatomic 3D-Printed Endoprosthetic With Multiligament Reconstruction After En Bloc Resection in Giant Cell Tumor of Distal Radius.

A 34-year-old woman was diagnosed with a giant cell tumor of the right distal radius with extensive articular invasion. After en-bloc resection of 5.5 cm of the distal radius, reconstruction was done with three-dimensional printing custom-made distal radius prosthesis. In addition, a multiligament reconstruction was done to prevent postoperative radiocarpal subluxation and imitate the native distal radius. At 18 months, the range of motion was 20° dorsiflexion, 10° palmar flexion, 10° supination, and 60° pronation. Her grip strength was 60% compared with the contralateral side. No complications were seen during this 2-year follow-up. We present the combined 3-dimensional printed custom-made prosthetic with multiligament reconstruction as an innovative method without postoperative complication at 2 years.

Rotationplasty for Unplanned Fixation of Pathological Fracture Distal Femoral Osteosarcoma.

INTRODUCTION: Rotationplasty had been reported as a salvage procedure for many decades. However, this procedure has not been used for unplanned fixation for pathological fracture of osteosarcoma. Therefore, this is the first case report of rotationplasty for this particular indication. Case Presentation. We report a case of a 22-year-old Thai female patient who sustained a supracondylar fracture at the distal femur and underwent a surgical treatment by open reduction and internal fixation with a distal femoral locking plate and screws. Follow-up radiographic imaging revealed that there were abnormal osteolytic lesions, and conventional high-grade osteosarcoma was diagnosed by a pathological study. There were no distant metastases from Computed Tomography (CT) scan or Technitium-99m bone scintography. After discussing with the patient for treatment options, rotationplasty was chosen for her definitive treatment after 3 courses of neoadjuvant chemotherapy. All of the contaminated tissues were removed during the surgery. The neurovascular bundles were preserved. A standard rotationplasty type A-1 according to the Winkelmann Classification was performed. Postoperative imaging showed satisfactory outcomes, and the wound healed uneventfully. The patient was able to move her ankle as a knee, and external prosthetic fitting was made. Adjuvant chemotherapy was given after a free margin with good tumor necrosis which was achieved as shown in the pathological study. At the patient's 3-year follow-up visit, she has stable size of lung nodules. She can walk with external prosthesis, limping slightly. Her new knee could move as expected, and she was satisfied with the result of the treatment. CONCLUSION: Rotationplasty for unplanned fixation of pathological fracture is a complex procedure. Patients often do not select this type of treatment because of the cosmetic acceptance even though it yields a good functional result. Therefore, awareness of the pathological fracture should initially be taken into account to prevent inappropriate fixation which could result in an unnecessary amputation.

Potential role of Bacillus Calmette-Guérin (BCG) vaccination in COVID-19 pandemic mortality: Epidemiological and Immunological aspects.

SARS-CoV-2 had already killed more than 400,000 patients around the world according to data on 7 June 2020. Bacillus Calmette-Guérin (BCG) vaccine is developed from live-attenuated Mycobacterium bovis, which is a microorganism found in a cow. Discovered by Dr. Albert Calmette and Camille Guérin since 1921, the BCG has served as a protection against tuberculosis and its complications. It is noticeable that countries which use mandatory BCG vaccination approach had lower COVID-19 infection and death rate. Current review aims to clarify this issue through epidemiological illustration of correlation between national BCG immunization and COVID-19 mortality, in addition to biological background of BCG-induced immunity Epidemiological data shows that universal BCG policy countries have lower median mortality rate compare to countries with past universal BCG policy and non-mass immunization BCG. (18 May 2020). Still, the links between BCG vaccination and better COVID-19 situation in certain countries are unclear, and more data on actual infection rate using SAR-CoV-2 antibody testing in large population sample is crucial for disease spreading comparison. Two immunological mechanisms, heterologous effects of adaptive immunity and trained innate immunity which induced by BCG vaccination, may explain host tolerance against COVID-19 infection, however, there is no direct evidence to support this biological background. Clinical trials related to BCG vaccination against COVID-19 are under investigation. Without a strong evidence, BCG must not be recommended for COVID-19 prevention, although, this should not be absolute contraindication. Risk of local and systemic complications from the vaccine should be informed to individual, who request BCG immunization.

Alu hypermethylation and high oxidative stress in patients with musculoskeletal tumors.

BACKGROUND: Alu is one of the non-autonomous element retrotransposons, constituting nearly 11% of the human DNA. Methylation changes of the Alu element can cause genomic instability, a hallmark of cancer development, ultimately leading to the development of cancer. Epigenetic factors may induce the aberrant methylation of Alu and also oxidative stress. However, current knowledge of Alu methylation and oxidative stress is limited. There are few studies that have evaluated Alu methylation and oxidative stress on musculoskeletal tumor progression. Therefore, the present study evaluated the status of Alu methylation in musculoskeletal (MS) tumor, adjacent tissues, and blood leukocytes from MS tumor subjects, as well as unaffected participants. Moreover, we also investigated the oxidative stress status in MS tumor subjects and the control participants and determined the correlation between Alu methylation in MS tumors and that in blood leukocytes. METHODS: Musculoskeletal tumors from musculoskeletal tumor patients (n = 40) were compared to adjacent tissues (n = 40). The blood leukocytes from musculoskeletal tumor patients were compared to the blood leukocytes from controls (n = 107). Alu methylation status was analyzed using quantitative combined bisulfite restriction analysis (COBRA). In addition, 8-hydroxy 2'-deoxyguanosine (8-OHdG) values were determined using enzyme-linked immunosorbent assay. RESULTS: Alu methylation values in MS tumors were statistically significantly higher than those in adjacent tissues (P = 0.035). Similarly, Alu methylation statuses in the blood leukocytes of MS tumor subjects were statistically greater than those of control participants (P < 0.001). Moreover, there was a positive association between Alu methylation levels in MS tumors and blood leukocytes (r = 0.765, P < 0.001). In addition, the highest tertile was significantly associated with the risk of MS tumors (OR = 14.17, 95% CI [5.08-39.51]; P < 0.001). The 8-OHdG values in MS tumors were statistically higher than in adjacent tissues (P < 0.001) and circulating 8-OHdG levels were substantially greater in MS tumor subjects than in the control participants (P < 0.001). DISCUSSION: These findings suggest that Alu methylation in blood leukocytes and plasma 8-OHdG might represent non-invasive biomarkers to help diagnose MS tumors. Therefore, Alu hypermethylation and high oxidative stress might be involved in the pathogenesis of the musculoskeletal tumors.

Tail of Superficial Myxofibrosarcoma and Undifferentiated Pleomorphic Sarcoma After Preoperative Radiotherapy.

BACKGROUND/AIM: Superficial myxofibrosarcoma (MFS) and undifferentiated pleomorphic sarcoma (UPS) are highly associated with infiltrative growth (tail sign) and local recurrence, but the impact of preoperative radiotherapy is uncertain. PATIENTS AND METHODS: Eight consecutive superficial MFS and 10 superficial UPS cases treated with preoperative radiotherapy and surgery were reviewed. Pathological response, surgical margin and magnetic resonance imaging (MRI) were retrospectively evaluated. Oncological events were reported in a descriptive form. RESULTS: Pathologically, nearly-complete response was observed in six UPS cases. Tail sign was pathologically detected in 13 cases, eight of which remained viable. Among the eight cases with viable tail, three cases, including two with positive margin, locally recurred. No major discrepancy was observed between tail length on pre-treatment T1-weighted post-contrast, fat-saturated MRI and pathological tail length. CONCLUSION: Tail of superficial MFS and UPS can retain viability even after radiotherapy and cause local recurrence unless they respond to radiotherapy well. Wider resection including the tail on MRI is recommended.

Outcomes of unplanned sarcoma excision: impact of residual disease.

This study aimed to compare the oncological results between unplanned excision (UE) and planned excision (PE) of malignant soft tissue tumor and to examine the impact of residual tumor (ReT) after UE. Nonmetastatic soft tissue sarcomas surgically treated in 1996-2012 were included in this study. Disease-specific survival (DSS), metastasis-free survival (MFS), and local-recurrence-free survival (LRFS) were stratified according to the tumor location and American Joint Committee on Cancer Classification 7th edition stage. Independent prognostic parameters were identified by Cox proportional hazard models. Two-hundred and ninety PEs and 161 UEs were identified. Significant difference in oncological outcome was observed only for LRFS probability of retroperitoneal sarcomas (5-year LRFS: 33.0% [UE] vs. 71.0% [PE], P = 0.018). Among the 142 UEs of extremity and trunk, ReT in re-excision specimen were found in 75 cases (53%). UEs with ReT had significantly lower survival probabilities and a higher amputation rate than UEs without ReT (5-year DSS: 68.8% vs. 92%, P < 0.001; MFS: 56.1% vs. 90.9%, P < 0.001; LRFS: 75.8% vs. 98.4%, P = <0.001; amputation rate 18.5% vs. 1.8%, P = 0.003). The presence of ReT was an independent poor prognostic predictor for DSS, MFS, and LRFS with hazard ratios of 2.02 (95% confidence interval (CI), 1.25-3.26), 1.62 (95% CI, 1.05-2.51) and 1.94 (95% CI, 1.05-3.59), respectively. Soft tissue sarcomas should be treated in specialized centers and UE should be avoided because of its detrimental effect especially when ReT remains after UE.

Intramedullary nailing has sufficient durability for metastatic femoral fractures.

BACKGROUND: Surgical treatment options of femoral metastases include intramedullary nailing (IMN) and endoprosthetic reconstruction (EPR). Previous studies have demonstrated functional and oncological advantages of EPR over IMN. The purpose of this study was to (1) report the durability of IMN and (2) establish the indication of IMN for femoral metastases. METHODS: In 2003-2013, among 186 surgically treated femoral metastasis cases, we retrospectively reviewed 80 consecutive IMN cases in 75 patients, including 14 pathological and 66 impending fractures. For the decision of surgical procedure (IMN, EPR, or plating), the following factors are considered: (1) fracture pattern (impending or pathological fracture), (2) Mirels' score (≥8 or <8), (3) fracture site (femoral head, neck, intertrochanter, subtrochanter, diaphysis, or distal), (4) number of metastases (solitary or multiple), and (5) patient's estimated prognosis. Patient demographics, postoperative survival, implant survival, and early postoperative mortality were reviewed. RESULTS: The patients were 37 males and 38 females, with a mean age of 60.1 (20-84) years. Average follow-up period was 11.4 (1-77) months. The most common fracture site was the subtrochanter (46/80), followed by the diaphysis (26/80) and the intertrochanter (8/80). The most common primary tumor was lung cancer (24/80, 32%), followed by breast cancer (24%) and melanoma (15%). With the exception of six cases, all patients underwent postoperative radiotherapy to the affected whole femur. The postoperative patient survival was 14.2 and 8.4% at 2 and 3 years from surgery, respectively, while the implant survival rate remained 94.0% at both 2 and 3 years. Three out of 46 subtrochanteric cases required revision surgeries because of proximal breakage of implant 4-50 months after initial surgery for femoral metastases, but all were replaced by mega-prosthesis and did not need further operation until their death. Early postoperative fatal complications were observed in three patients, all of which were pulmonary dysfunction. CONCLUSIONS: The performance of IMN in this study was satisfactory although a large portion of sub- and intertrochanter metastases were included. Broader indication including these parts should be considered, for IMN has advantages such as lower cost and less invasiveness and even an implant failure can be revised by mega-prosthetic reconstruction.

Modification of human cancellous bone using Thai silk fibroin and gelatin for enhanced osteoconductive potential.

The modification of human cancellous bone (hBONE) with silk fibroin/gelatin (SF/G) using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC)/N-hydroxysuccini-mide (NHS) crosslinking was established. The SF/G solutions at a weight ratio of 50/50 and the solution concentrations of 1, 2, and 4 wt % were studied. SF/G sub-matrix was formed on the surface and inside pore structure of hBONE. All hBONE scaffolds modified with SF/G showed smaller pore sizes, less porosity, and slightly lower compressive modulus than unmodified hBONE. SF/G sub-matrix was gradually biodegraded in collagenase solution along 4 days. The hBONE scaffolds modified with SF/G, particularly at 2 and 4 wt % solution concentrations, promoted attachment, proliferation, and osteogenic differentiation of bone marrow-derived mesenchymal stem cells (MSC), comparing to the original hBONE. The highest cell number, ALP activity and calcium production were observed for MSC cultured on the hBONE scaffolds modified with 4 wt % SF/G. The mineralization was also remarkably induced in the cases of modified hBONE scaffolds as observed from the deposited calcium phosphate by EDS. The modification of hBONE with SF/G was, therefore, the promising method to enhance the osteoconductive potential of human bone graft for bone tissue engineering.

In vitro effects of thermoablation on apoptosis of giant cell tumor of bone: a preliminary report.

BACKGROUND: Giant cell tumor of bone is a common benign aggressive bone tumor. Recurrent rate in the patients who have the tumor with soft tissue invasion is rather high. Use of strong chemicals such as phenol and liquid nitrogen to lessen the recurrent rate might not be used in this lesion. OBJECTIVE: The experiment was carried out to discover apoptotic effects of thermoablation on giant cell tumor of bone to find out a possibility to use thermoablation in the clinic in the patients with extensive lesion. MATERIAL AND METHOD: Tumor cell suspension was prepared from 4 patients who had definite diagnosis of giant cell tumor of bone. The tumor cells were subjected to thermoablation at 45, 47 and 50 degrees C for 10 to 30 minutes before were cultured at 37 degrees C for another 3 days. Osteoblasts and chondrocytes from the last 3 patients were collected,prepared and underwent thermoablation in the same fashion. Apoptosis of tumor cells, chondrocytes and osteoblasts were carried out by the use of flow cytometry. RESULTS: Thermoablation at 47 degrees C for 30 minutes resulted in < 50% chondrocyte and osteoblast apoptosis and 70-90% tumor cells apoptosis of 3/4 patients. Thermoablation at 47 and 50 degrees C for 20 to 30 minutes has more negative effect on giant cell tumor of bone than chondrocytes and osteoblasts. CONCLUSION: Thermoablation might be a useful tool for local tumor control in the clinic.