Dimensional accuracy and precision and surgeon perception of additively manufactured bone models: effect of manufacturing technology and part orientation.

BACKGROUND: Additively manufactured (AM) anatomical bone models are primarily utilized for training and preoperative planning purposes. As such, they must meet stringent requirements, with dimensional accuracy being of utmost importance. This study aimed to evaluate the precision and accuracy of anatomical bone models manufactured using three different AM technologies: digital light processing (DLP), fused deposition modeling (FDM), and PolyJetting (PJ), built in three different part orientations. Additionally, the study sought to assess surgeons' perceptions of how well these models mimic real bones in simulated osteosynthesis. METHODS: Computer-aided design (CAD) models of six human radii were generated from computed tomography (CT) imaging data. Anatomical models were then manufactured using the three aforementioned technologies and in three different part orientations. The surfaces of all models were 3D-scanned and compared with the original CAD models. Furthermore, an anatomical model of a proximal femur including a metastatic lesion was manufactured using the three technologies, followed by (mock) osteosynthesis performed by six surgeons on each type of model. The surgeons' perceptions of the quality and haptic properties of each model were assessed using a questionnaire. RESULTS: The mean dimensional deviations from the original CAD model ranged between 0.00 and 0.13 mm with maximal inaccuracies < 1 mm for all models. In surgical simulation, PJ models achieved the highest total score on a 5-point Likert scale ranging from 1 to 5 (with 1 and 5 representing the lowest and highest level of agreement, respectively), (3.74 ± 0.99) in the surgeons' perception assessment, followed by DLP (3.41 ± 0.99) and FDM (2.43 ± 1.02). Notably, FDM was perceived as unsuitable for surgical simulation, as the material melted during drilling and sawing. CONCLUSIONS: In conclusion, the choice of technology and part orientation significantly influenced the accuracy and precision of additively manufactured bone models. However, all anatomical models showed satisfying accuracies and precisions, independent of the AM technology or part orientation. The anatomical and functional performance of FDM models was rated by surgeons as poor.

As simple as it sounds? The treatment of simple bone cysts in the proximal femur in children and adolescents: Retrospective multicenter EPOS study of 74 patients.

Purpose: Simple bone cysts are among the most prevalent benign cystic tumor-like lesions in children. Proximal femoral simple bone cysts may require specific treatment because of increased fracture risk. With limited literature available on this specific localization, consensus regarding optimal treatment is lacking. We present a large international multicenter retrospective cohort study on proximal femoral simple bone cysts. Methods: All consecutive pediatric patients with proximal femoral simple bone cyst from 10 tertiary referral centers for musculoskeletal oncology were included (2000-2021). Demographics, primary treatment, complications, and re-operations were evaluated. Primary outcomes were time until full weight-bearing and failure-free survival. Results: Overall, 74 simple bone cyst patients were included (median age 9 years (range = 2-16), 56 (76%) male). Median follow-up was 2.9 years (range = 0.5-21). Index procedure was watchful waiting (n = 6), percutaneous procedure (n = 12), open procedure (n = 50), or osteosynthesis alone (n = 6). Median time until full weight-bearing was 8 weeks (95% confidence interval = 0.1-15.9) for watchful waiting, 9.5 (95% confidence interval = 3.7-15.3) for percutaneous procedure, 11 (95% confidence interval = -0.7 to 13.7) for open procedure, and 6.5 (95% confidence interval = 5.9-16.1) for osteosynthesis alone (p = 0.58). Failure rates were 33%, 58%, 29%, and 0%, respectively (p = 0.069). Overall failure-free survival at 1, 2, and 5 years was 77.8% (95% confidence interval = 68.2-87.4), 69.5% (95% confidence interval = 58.5-80.5), and 62.0% (95% confidence interval = 47.9-76.1), respectively. Conclusion: A preferred treatment for proximal femoral simple bone cysts remains unclear, with comparable failure rates and times until full weight-bearing. Watchful waiting may be successful in certain cases. If not feasible, osteosynthesis alone can be considered. Treatment goals should be cyst control, minimizing complications and swift return to normal activities. Therefore, an individualized balance should be made between undertreatment, with potentially higher complication risks versus overtreatment, resulting in possible larger interventions and accompanying complications. Level of evidence: Level IV, retrospective multicentre study.

High fibrinogen levels are associated with poor survival in patients with liposarcoma.

The aim of this study was to evaluate whether (preoperative) plasma levels of fibrinogen, an essential clotting and acute phase protein, are associated with the prognosis of patients with a liposarcoma, a subtype of sarcoma derived from adipose tissue. We performed a retrospective cohort study of 158 patients with liposarcoma treated at the Department of Orthopaedics of the Medical University of Vienna in Austria from May 1994 to October 2021. Kaplan-Meier curves as well as uni- and multivariable Cox proportional hazard models were performed to evaluate the association between fibrinogen levels and overall survival. Elevated fibrinogen was associated with adverse overall survival in cause specific hazards analysis of mortality (hazard ratio [HR] per 10 mg/dL increase: 1.04; 95% CI 1.02-1.06; p < 0.001). This association prevailed in multivariable analysis after adjustment for AJCC tumor stage (HR 1.03; 95% CI 1.01-1.05; p = 0.013). Increasing levels of fibrinogen, a routinely available and inexpensive parameter, predicts the risk of mortality in patients with liposarcoma.

Patient-Specific Guides for Accurate and Precise Positioning of Osseointegrated Implants in Transfemoral Amputations: A Proof-of-Concept In Vitro Study.

Background and Objectives: The treatment of transfemoral amputees using osseointegrated implants for prosthetic anchorage requires accurate implant positioning when using threaded bone-anchoring implants due to the curvature of the femur and the risk of cortical penetration in misaligned implants. This study investigated the accuracy and precision in implant positioning using additively manufactured case-specific positioning guides. Materials and Methods: The geometry and density distribution of twenty anatomic specimens of human femora were assessed in quantitative computed tomography (QCT) scanning. The imaging series were used to create digital 3D specimen models, preoperatively plan the optimal implant position and manufacture specimen-specific positioning guides. Following the surgical bone preparation and insertion of the fixture (threaded bone-anchoring element) (OPRA; Integrum AB, Mölndal, Sweden), a second QCT imaging series and 3D model design were conducted to assess the operatively achieved implant position. The 3D models were registered and the deviations of the intraoperatively achieved implant position from the preoperatively planned implant position were analyzed as follows. The achieved, compared to the planned implant position, was presented as resulting mean hip abduction or adduction (A/A) and extension or flexion (E/F) and mean implant axis offset in medial or lateral (M/L) and anterior or posterior (A/P) direction measured at the most distal implant axis point. Results: The achieved implant position deviated from the preoperative plan by 0.33 ± 0.33° (A/A) and 0.68 ± 0.66° (E/F) and 0.62 ± 0.55 mm (M/L) and 0.68 ± 0.56 mm (A/P), respectively. Conclusions: Using case-specific guides, it was feasible to achieve not only accurate but also precise positioning of the implants compared to the preoperative plan. Thus, their design and application in the clinical routine should be considered, especially in absence of viable alternatives.

Patients' perception of changes and consequences after tumor resection : A qualitative study in Austrian patients with musculoskeletal malignancies.

OBJECTIVE: The aim of this study was to investigate the effects and consequences of surgical treatment of patients with musculoskeletal malignancies on everyday life. METHODS: A modified form of grounded theory was used for data collection and analysis. Data collection was systematic and analyzed simultaneously and 16 interviews were conducted: 2 narrative, 11 guided and 3 expert interviews (surgeon, physical therapist, support group). Data collection and analysis alternated until no new codes could be found. Once theoretical saturation was achieved, the main category was formed and described using the literature. RESULTS: The main category results from the combination of all categories and leads to the core category. In the center is the affected person and in the immediate environment are the patient's relatives/partners. In the next instance the primary care physician is necessary to establish a sense of normalcy. This depends on the individuality of the person and the restored possibilities of movement. CONCLUSION: Based on the results, the necessity of implementing psychosocial care involving the social environment is shown. The importance of relatives/partners for recovery is emphasized. Furthermore, the communication between the specialists and family physicians should be simplified.

One Health Education Nexus: enhancing synergy among science-, school-, and teacher education beyond academic silos.

Introduction: The fact that the daily lives of billions of people were affected by the medical, social, and political aspects of the SARS-CoV-2 pandemic shows the need to anchor the understanding of One Health in society. Hence, promoting awareness and deepening the understanding of the interrelation between human health, animal health, and ecosystems must be accomplished through quality education, as advocated by UN Sustainable Development Goal 4. The often-questioned and discussed measures taken by governments to control the global pandemic between 2020 and 2023 can be seen as an opportunity to meet the educational needs of civil society solutions in multi-stakeholder settings between public, universities, and schools. Methods: This paper focuses on the integration of One Health principles in educational frameworks, particularly within the context of the higher education teaching framework "Teaching Clinic." This master-level course in the domain of pre-service teacher education serves as a potent vehicle for facilitating One Health Education, bridging the gap between research, higher education, and schools. Through the presentation of two case studies, this article demonstrates how the Teaching Clinic approach fosters interdisciplinary perspectives and provides a dynamic learning environment for pre-service teachers, as well as for pupils involved in the educational process. Results: In both cases, the integration of educational One Health school teaching-learning settings effectively enhanced pupils' understanding of complex topics and engaged them in active learning experiences. Pre-service teachers played a crucial role in developing, implementing, and evaluating these interventions. In Case I, pupils demonstrated proficiency in analyzing data and evaluating mathematical models, while in Case II, the chosen instructional approach facilitated One Health knowledge acquisition and enjoyment among pupils. These results underscore the potential of the One Health Teaching Clinic as a valuable educational framework for enhancing teaching and learning outcomes for pre-service teachers and fostering pupil engagement in socio-scientific One Health-related topics. Discussion: The discussion delves into the significance of breaking down disciplinary silos and the crucial role of teacher education in promoting a holistic approach to education, emphasizing the intersectionality of One Health Education and Education for Sustainable Development. This article underpins the significance of collaborative efforts across multiple (scientific) disciplines and across secondary and tertiary education levels to reach a nexus. Moreover, it emphasizes the alignment of this approach with the 2030 Agenda, Education for Sustainable Development, and Sustainable Development Goals, highlighting the potential for collective action toward a more sustainable future.

What sports activity levels can be achieved in the long-term after major lower extremity amputation for malignant tumors? - A minimum follow-up of twenty years.

BACKGROUND: It is well-known that exercise through sports and physical activity has beneficial effects on health. After lower extremity amputation, low rates of participation in sports activities have been shown. So far, there is only limited scientific long-term information concerning sports activity and feasible types of sports in patients with lower extremity amputations due to malignant tumors. This study sought to provide very long-term information about the following questions: (1) What sports activity levels can be achieved after lower extremity amputation due to a malignant tumor? (2) What are feasible types of sports? (3) Is the University of California Los Angeles (UCLA) Activity Score influenced by patient's age, the age at the time of surgery and the amount of prosthesis sockets used to date? HYPOTHESIS: Patients with lower extremity amputation due to a malignant tumor cannot regularly participate in moderate sports activities (UCLA Activity Score≥6) in the very long-term. MATERIALS AND METHODS: In a retrospective questionnaire survey, 21 former patients (seven females, 14 males; median age: 60.5years [range: 33-74]) who underwent an amputation of the lower extremity (14 transfemoral, four knee disarticulations, three transtibial) from 1961 to 1993 due to a malignant tumor were interviewed. The median follow-up was 41.1years (range: 23-55). The patients were interviewed about types of sports, frequencies and durations of sports sessions at the time of the last follow-up, as well as retrospectively. Sports activity levels were then assessed based on the UCLA Activity Score. Demographic background, data on amputation level, histological results, prosthetic devices and revision surgeries were collected. RESULTS: Seven patients (33%) were still regularly exercising at least moderate sports activities at the last follow-up, including one patient regularly participating in impact sports. The preoperative median UCLA Activity Score of 9 (range: 2-10) decreased to 5 (range: 2-10) at the last follow-up (p<0.001). Swimming (13 patients, seven on a regular basis), cycling (seven), downhill skiing (five) and hiking (four) were among the most common feasible types of sports. Increasing age had a negative influence on the UCLA Activity Score [95% CI (-0.034, -0.006); RB=-0.020; SD=0.0074; p=0.007]. CONCLUSION: After a major amputation in the lower extremity due to a malignant tumor, high activity levels by practicing types of sports such as downhill skiing, are achievable. In the very long-term, a regular participation in at least moderate activities, such as swimming, is possible. Programs for physical and sports activities, based on recommendations drawn from long-term experience, are necessary and should be individually tailored to amputees and their limitations. LEVEL OF EVIDENCE: IV.

[Evidence in Infiltrative Pain Therapy of the Musculoskeletal System]. / Evidenz in der infiltrativen Schmerztherapie des Bewegungsapparates.

Musculoskeletal pain symptoms frequently generate limitations in daily work and life in many patients. Usually, symptomatic treatment is possible before clarifying the in depth diagnosis. A symptom-based infiltration therapy will never replace a thoroughly done physical examination and thoughtful collection of patient history, however, it can be of great benefit for the patient when done focused on the point of pain and executed with profound anatomical knowledge. Furthermore, the knowledge of the level of evidence of therapeutic infiltrations improves their outcomes and shapes realistic patients' expectations. Ultrasound-guided therapeutic infiltrations improve the outcome despite the use of lower amounts of active agents by pinpointed applications. This article provides an overview of the scientific evidence of effectiveness of (ultrasound-guided) infiltration techniques in diverse musculoskeletal regions.

Specific knowledge and resilience affect short-term outcome in patients following primary total hip arthroplasty.

PURPOSE: The aim of the present study was to investigate the potential associations between specific knowledge, resilience and patient-reported outcome measures (PROMS) following primary total hip arthroplasty (THA). METHODS: In a cross-sectional prospective study, consecutive patients following primary THA were included at a rehabilitation center. A novel knowledge score and the validated Connor Davidson Resilience Scale (CD-RISC) were utilized to assess patients' specific knowledge and resilience, respectively. Additionally, patients completed a qualitative questionnaire regarding the information they had received. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), as well as the University of California and Los Angeles Score (UCLA) served as primary outcome measures. Stepwise multiple regression analysis was performed to identify potential predictors of outcome. RESULTS: A total of 103 patients at a mean age of 67.5 years (SD 10.5, 38-88) were included in the analysis at a median of 55.5 days (IQR 43-81) following primary THA. The mean knowledge and resilience scores were 3.8 (SD 1.6, 0-7) and 69.5 (SD 18.5, 0-100), respectively. Forty-seven percent of patients were afraid of harming their prosthesis and these patients had up to 59% worse WOMAC scores (p < 0.001). WOMAC scores on admission to rehabilitation were predicted by resilience and knowledge scores (R2 = 0.106, p = 0.036). UCLA scores at the time of admission were predicted by knowledge scores (R2 = 0.078, p = 0.007). CONCLUSION: The present study demonstrated that patients with a feeling of uncertainty had an inferior short-term functional outcome following primary THA. Moreover, it could be shown that higher specific knowledge and resilience are associated with a better functional outcome according to validated PROMS. While these findings need to be prospectively validated in future studies, specific patient knowledge and resilience may have a direct impact on the outcome of primary THA.

Thermal Effects during Bone Preparation and Insertion of Osseointegrated Transfemoral Implants.

BACKGROUND: The preparation of bone for the insertion of an osseointegrated transfemoral implant and the insertion process are performed at very low speeds in order to avoid thermal damages to bone tissue which may potentially jeopardize implant stability. The aim of this study was to quantify the temperature increase in the femur at different sites and insertion depths, relative to the final implant position during the stepwise implantation procedure. METHODS: The procedure for installation of the osseointegrated implant was performed on 24 femoral specimens. In one specimen of each pair, the surgery was performed at the clinically practiced speed, while the speed was doubled in the contralateral specimen. Six 0.075 mm K fine gauge thermocouples (RS Components, Sorby, UK) were inserted into the specimen at a distance of 0.5 mm from the final implant surface, and six were inserted at a distance of 1.0 mm. RESULTS: Drilling caused a temperature increase of <2.5 °C and was not statistically significantly different for most drill sizes (0.002 < p < 0.845). The mean increase in temperature during thread tapping and implant insertion was <5.0 °C, whereas the speed had an effect on the temperature increase during thread tapping. CONCLUSIONS: Drilling is the most time-consuming part of the surgery. Doubling the clinically practiced speed did not generate more heat during this step, suggesting the speed and thus the time- and cost-effectiveness of the procedure could be increased. The frequent withdrawal of the instruments and removal of the bone chips is beneficial to prevent temperature peaks, especially during thread tapping.

Diagnostic accuracy of ultrasound-guided core needle biopsy versus incisional biopsy in soft tissue sarcoma: an institutional experience.

Core needle biopsy (CNB) is gaining in importance due to its advantages in the matter of patient morbidity, time and cost. Nevertheless, controversies still exist regarding the biopsy technique of choice for the accurate diagnosis of soft tissue sarcoma (STS). This retrospective cohort study compared the diagnostic performance between ultrasound-guided CNB and incisional biopsy (IB), both performed by orthopedic surgeons. The aims of the study were to answer the following questions: (1) Is ultrasound-guided CNB a highly reliable modality for diagnosing STSs? (2) Is CNB equally useful to IB for identifying histologic subtype? (3) Had patients who underwent CNB a reduced risk of complications? One-hundred and fifty-three patients who underwent resection of soft tissue sarcoma were classified into two groups according to biopsy technique prior to surgery; CNB group (n = 95) and IB group (n = 58). The final surgical specimens were in 40 patients liposarcoma (myxoid, pleomorphic and dedifferentiated), 39 undifferentiated pleomorphic sarcoma (UPS), 33 myxofibrosarcoma, 10 synovial sarcoma, 10 leiomyosarcoma and in the remaining 21 patients different soft tissue sarcoma entities. Sarcoma location of 71 patients was in the thigh, 19 in the lower leg, 22 in the upper arm and shoulder area; 10 in the knee and gluteal region, 9 in the thoracic region, the residual 12 in other body areas. Malignancy was correctly diagnosed in 87% (83 of 95) for the CNB group and 93% (54/58) for the IB group. Correct identification rate of histologic subtype was 80% (76 of 95) in the CNB group and 83% (48 of 58) in the IB group. There were no significant differences in the correct diagnosis rates of malignancy and subtype between the two techniques. No complications were seen in the CNB group, whereas 2 patients in whom IB was performed developed pulmonary embolism and 1 patient surgical site infection. Ultrasound-guided CNB is highly accurate and not inferior to IB in diagnosing the dignity of lesions and histologic subtype in patients with suspected STSs.

Cross-cultural adaption, translation and validation of the Toronto extremity salvage score (TESS) for patients in German-speaking countries.

OBJECTIVE: The preferred treatment for malignant bone and soft tissue tumors is limb salvage surgery; the Toronto extremity salvage score (TESS) is commonly used to measure physical functioning of the affected extremity. The aims of this study were to translate and culturally adapt the German version of the TESS, as well as to explore its convergent reliability, validity and re-test reliability. STUDY DESIGN: Patients (n = 50) 32 lower extremity (LE) and 18 upper extremity (UE) were asked to fill out the German TESS two times (t1: clinical visit, t2: regular email) and the SF-36 once. METHODS: The TESS questionnaires were translated from English into German, back translated into English, and culturally adapted. The reliability was assessed with Cronbach's alpha (α). The validity was measured with the SF-36 physical component score and TESS using the Spearman rank correlation coefficient (r). Furthermore, the test-retest reliability was calculated with the intraclass correlation coefficient (ICC). RESULTS: Internal consistency for both questionnaires was excellent (LE t1: α = 0.924, t2: α = 0.952; UE t1: α = 0.957, t2: α = 0.898). A statistically significant correlation was found between the SF-36 physical component scale and the German TESS (LE r = 0.741, UE r = 0.713). The ICC between baseline (t1) and re-test (t2) was 0.952 and 0.871 for the lower and upper extremities, respectively. CONCLUSION: Initial evidence demonstrated that the German TESS is a valid and reliable instrument for use with patients after surgical treatment of malignant bone or soft tissue sarcoma.

Higher patient knowledge and resilience improve the functional outcome of primary total knee arthroplasty.

BACKGROUND: A significant percentage of patients have an unfavorable outcome following primary total knee arthroplasty (TKA). This study aimed to evaluate whether specific knowledge about the implant and resilience can influence the functional outcome following TKA. METHODS: A consecutive series of 163 patients following primary TKA at a mean age of 70 years (SD 9.1 years) were included at a regional rehabilitation center between December 2015 and December 2016. Specific patient knowledge (scale 0-7), Connor Davidson Resilience Scale (CD-RISC), Western Ontario and McMaster Universities (WOMAC) score, University of California and Los Angeles (UCLA) score and constitutional parameters were assessed on admission. Pearson's correlation analysis and stepwise linear regression analysis were performed to investigate associations between knowledge, resilience and functional scores. RESULTS: The mean overall knowledge score was 3.5 out of 7 and the mean resilience score was 72.9 out of 100. Mean WOMAC and UCLA scores on admission were 23.8 and 5.5, respectively. Stepwise linear regression analysis identified knowledge and age as significant predictors of WOMAC scores (R2 = 14.3%, p = 0.003). Knowledge and resilience were identified as significant predictors of UCLA scores (R2 = 13.8%, p = 0.013). CONCLUSION: This study highlights the importance of patient-related factors as part of an integral patient care concept in TKA. Although the identified predictors still need to be refined, it could be demonstrated how better patient knowledge might ultimately lead to better functional outcome following TKA. Routinely assessing patients' resilience might be a useful tool to identify patients at risk for low activity levels. LEVEL OF EVIDENCE: III. Patient-reported outcome study.

How Common Are Chronic Residual Limb Pain, Phantom Pain, and Back Pain More Than 20 Years After Lower Limb Amputation for Malignant Tumors?

BACKGROUND: After major lower limb amputation, persistent pain is common, with up to 85% of patients reporting recurring phantom or residual-limb pain. Although pain management is an important factor of quality of life in patients with lower limb amputations, there are few long-term data regarding the frequency of persistent pain and how it impacts prosthesis use. QUESTIONS/PURPOSES: (1) How prevalent are different types of pain at long-term follow-up after amputation for malignant tumors? (2) What association do different pain types have with daily prosthesis use? METHODS: Between 1961 and 1995, 124 major amputations for malignant tumors were performed at one center in Austria in patients (1) who spoke German and (2) whose surgical date resulted in the possibility of a minimum follow-up time of 20 years at the time of this survey; those patients were considered potentially eligible for this retrospective study. The indications for major amputation were to achieve local tumor control in limbs that the surgeon deemed unsalvageable without amputation. Of those 124 patients, 71% (88) had died, 9% (11) could not be reached, and 3% (4) declined to participate. Thus, 58% (21 of 36) of those living at the time of this study and who underwent lower limb amputation between 1961 and 1993 with a median (range) follow-up duration of 41 years (23 to 55) completed a standardized questionnaire, including an assessment of pain and daily prosthesis use during the year before the survey. Phantom pain, residual limb pain, and back pain were each further subclassified into pain frequency, intensity, and restrictions in activities of daily living (ADL) due to the specific pain form and rated on a 5- (pain frequency) and 10-point (pain intensity, restrictions in ADL) numerical rating scale. Before multivariate regression analysis, daily prosthesis use was correlated with pain parameters using Spearman correlation testing. RESULTS: Seventeen of 21 patients reported phantom limb and back pain, and 15 patients reported residual limb pain in the past year. Median (range) phantom pain intensity was 7 (1 to 10) points, median residual limb pain intensity was 4 (1 to 9) points, and median back pain intensity was 5 (1 to 10) points. After controlling for relevant confounding variables such as age at amputation, age at survey, and stump length, we found that less intense residual limb pain (defined on a 10-point scale with 1 representing no pain at all and 10 representing extremely strong pain [95% CI 0.3 to 1.0]; r = 0.8; p = 0.003) was associated with greater daily prosthesis use. Higher amputation levels showed a decreased daily prosthesis use compared with patients with lower amputation levels (defined as transfemoral amputation versus knee disarticulation versus transtibial amputation [95% CI 0.3 to 5.1]; r = 0.5; p = 0.03). CONCLUSION: Decades after surgery, many patients with lower limb amputations experience pain that restricts them in terms of ADLs and decreases their daily prosthesis use. This information supports the need for regular residual limb inspections and careful prosthesis fitting even at long-term follow-up, as effective prosthesis fitting is a modifiable cause of residual limb pain. Future studies evaluating long-term treatment effects of pain relief surgery and therapeutic alternatives to conservative pain treatments should be performed, as these approaches may help alleviate pain in patients with refractory postamputation pain. LEVEL OF EVIDENCE: Level IV, therapeutic study.

What sports activity levels are achieved in long-term survivors with modular endoprosthetic humerus reconstruction following primary bone sarcoma resection?

BACKGROUND: The aim of the study was to assess (1) sports activity, (2) sports involving the upper extremities, (3) functional outcome and (4) sports-related complications of long-term survivors of primary malignant bone tumors of the proximal humerus. METHODS: A total of 18 patients with an endoprosthetic reconstruction for primary malignant bone sarcoma of the proximal humerus (8 male, 10 female, mean age 19.9 ± 8.4 years, range 7.8-37.4 years) with an average follow-up of 18.1 ± 7.4 years (range 6.7-29.8 years) were included. The type of sport, frequency, duration of each sport session and the University of California, Los Angeles (UCLA) activity score were assessed before surgery, at 1 year, 3 years and at the latest follow-up. Functional outcome was assessed by the Toronto extremity salvage score (TESS). RESULTS: The mean UCLA activity score decreased from 8.0 (±1.3, range 5-9) preoperative to 4.2 (±1.7, range 3-8) at 1­year follow-up (p < 0.05). After 3 years it increased to 5.1 (±1.75, range 3-8) and further to 7 (±1.8, range 4-9) at the last follow-up. The mean postoperative TESS was 80.8 (±6.4, range 75.7-91.4) at the latest follow-up. Patients who were initially more active without reconstruction including a synthetic mesh were more likely to develop soft tissue complications accompanied by proximal endoprothesis migration. CONCLUSION: Patients with a modular endoprosthetic reconstruction of the humerus following primary bone sarcoma resume participation in sports. Regarding the low incidence of periprosthetic infections, utilization of a synthetic mesh for reconstruction to prevent soft tissue complications in active patients should be considered.

What Opinions Do Tumor Reconstructive Surgeons Have about Sports Activity after Megaprosthetic Replacement in Hip and Knee? Results of the MoReSports Expert Opinion Online Survey.

Sports activity has many benefits in cancer survivors. A key one is having sport activity contribute to the well-being of the individual. However, there are no guidelines about the intensity and kind of postoperative mobility workouts after hip or knee megaprosthetic treatment. Opinion research about sports after modular bone and joint replacement may provide an understanding of surgeons' attitudes on sports activity after megaprostheses of the hip and knee joint. A web survey with members of three international professional organizations of orthopedic tumor reconstructive surgeons was conducted between September 2016 and January 2018. Members were invited via personalized emails by the European Musculoskeletal Oncology Society (EMSOS), the International Society of Limb Salvage (ISOLS), and the Musculoskeletal Tumor Society (MSTS). The questionnaire included 26 questions. A total of 149 surgeons started the survey, and 76 finished the entire survey (American Association for Public Opinion Research (AAPOR) second response rate (RR2) EMSOS: 12.3%; ISOLS: 21.9%; MSTS: n/a). More than half of the respondents encourage sarcoma survivors after megaprosthetic treatment to reach an activity level that would allow them to regularly participate in active sporting events of University of California, Los Angeles (UCLA) activity level 7 and higher. Orthopedic tumor reconstructive surgeons do fear a number of complications (periprosthetic fracture, allograft failure/fracture, loosening, prosthetic or bearing failure, and early polyethylene wear) due to sports activity after modular bone-joint replacement, but they actually witness fewer complications than they conceptually anticipated. According to the surgeons' opinions, between four to seven types of sports after surgery could reasonably be recommended depending on the type of hip or knee procedures. This survey provides insights into opinions on what could be recommended, what could be allowed if surgeons and their patients agree on the potential negative outcome, and which sports should definitely not be allowed after hip and knee megaprostheses.

Advanced techniques in amputation surgery and prosthetic technology in the lower extremity.

Bone-anchored implants give patients with unmanageable stump problems hope for drastic improvements in function and quality of life and are therefore increasingly considered a viable solution for lower-limb amputees and their orthopaedic surgeons, despite high infection rates.Regarding diversity and increasing numbers of implants worldwide, efforts are to be supported to arrange an international bone-anchored implant register to transparently overview pros and cons.Due to few, but high-quality, articles about the beneficial effects of targeted muscle innervation (TMR) and regenerative peripheral nerve interface (RPNI), these surgical techniques ought to be directly transferred into clinical protocols, observations and routines.Bionics of the lower extremity is an emerging cutting-edge technology. The main goal lies in the reduction of recognition and classification errors in changes of ambulant modes. Agonist-antagonist myoneuronal interfaces may be a most promising start in controlling of actively powered ankle joints.As advanced amputation surgical techniques are becoming part of clinical routine, the development of financing strategies besides medical strategies ought to be boosted, leading to cutting-edge technology at an affordable price.Microprocessor-controlled components are broadly available, and amputees do see benefits. Devices from different manufacturers differ in gait kinematics with huge inter-individual varieties between amputees that cannot be explained by age. Active microprocessor-controlled knees/ankles (A-MPK/As) might succeed in uneven ground-walking. Patients ought to be supported to receive appropriate prosthetic components to reach their everyday goals in a desirable way.Increased funding of research in the field of prosthetic technology could enhance more high-quality research in order to generate a high level of evidence and to identify individuals who can profit most from microprocessor-controlled prosthetic components. Cite this article: EFORT Open Rev 2020;5:724-741. DOI: 10.1302/2058-5241.5.190070.

Predicting Total Knee Replacement from Symptomology and Radiographic Structural Change Using Artificial Neural Networks-Data from the Osteoarthritis Initiative (OAI).

The aim of the study was to longitudinally investigate symptomatic and structural factors prior to total knee replacement (TKR) surgery in order to identify influential factors that can predict a patient's need for TKR surgery. In total, 165 participants (60% females; 64.5 ± 8.4 years; 29.7 ± 4.7 kg/m2) receiving a TKR in any of both knees within a four-year period were analyzed. Radiographic change, knee pain, knee function and quality of life were annually assessed prior to the TKR procedure. Self-learning artificial neural networks were applied to identify driving factors for the surgical procedure. Significant worsening of radiographic structural change was observed prior to TKR (p ≤ 0.0046), whereas knee symptoms (pain, function, quality of life) worsened significantly only in the year prior to the TKR procedure. By using our prediction model, we were able to predict correctly 80% of the classified individuals to undergo TKR surgery with a positive predictive value of 84% and a negative predictive value of 73%. Our prediction model offers the opportunity to assess a patient's need for TKR surgery two years in advance based on easily available patient data and could therefore be used in a primary care setting.

Biomechanical comparison of knotless vs. knotted suture anchors in the acetabular rim with respect to bone density.

BACKGROUND: Acetabular labral tears are managed with suture anchors providing good clinical outcomes. Knotless anchors are easier to use and have a quicker insertion time compared to knotted anchors. The purpose of this study was to compare the biomechanical behavior of two different anchor designs (knotted vs. knotless) in ultimate load testing in correlation with bone density in the acetabular rim. METHODS: Eighteen knotted Bio-FASTak and seventeen knotless PushLock anchors (both: Arthrex Inc., Naples, FL, USA) were inserted in the rims of two human acetabula, with known bone density distribution. The anchors were subjected to load-to-failure tests. Anchors were additionally tested in solid polyurethane foam with defined densities. FINDINGS: The Bio-FASTak group showed higher survival rates at 1, 2, and 3 mm displacement and was able to withstand significantly higher loads at 3 mm displacement (p = 0.031). There was no statistically significant difference in stiffness (p = 0.087), yield- (p = 0.190), and ultimate load (p = 0.222) between the two groups. Only the PushLock group showed correlation between bone volume over total volume (BV/TV) and stiffness (R = 0.750, p = 0.086) and between BV/TV and yield load (R = 0.838, p = 0.037). Experiments on solid polyurethane foam confirmed the correlation between the mechanical properties and tissue density for the same anchor. INTERPRETATION: PushLock shows similar biomechanical properties to the Bio-FASTak, but eliminates knot tying and potentially abrasive knots. In addition, biomechanical properties of the PushLock are governed by local bone density.