Readmissions at Thirty-Days and One-Year for Implant-Associated Complications following Primary Total Hip and Knee Arthroplasty: A Population-Based Study of 34,392 Patients Across Austria.

INTRODUCTION: The primary aim of this study was to assess 30-day and one-year rates for unplanned readmission due to implant-associated complications following total hip (THA) or total knee arthroplasty (TKA) in Austria. Secondary endpoints were reasons for readmission and differences in revision risk depending on demographics and hospital size. METHODS: Data on patients receiving THA (n = 18,508) or TKA (n = 15,884) in orthopaedic and trauma units across Austria within a one-year period (January 2021 to December 2021) was retrieved from a government-maintained database. The absolute and relative frequencies of unplanned readmissions were calculated. Risk factors for 30-day and one-year readmission following THA or TKA due to implant-associated complications were investigated. RESULTS: The thirty-day and one-year readmission rates for any implant-associated complication were 1.0% (339 of 34,392) and 3.0% (1,024 of 34,392). Relative to the overall readmission rate for any complication at 30 days (n = 1,952) and one year (n = 12,109), respectively, readmission rates for implant-associated complications were 17.4 and 8.5%. The thirty-day readmission rates were higher in THA (1.2%) than TKA patients (0.8%; P = 0.001), while it was the opposite at one year (THA, 2.7%; TKA, 3.3%; P < 0.001). Mechanical complications (554 of 1,024) were the most common reason for one-year readmission. Prolonged length of in-hospital stay independently associated with increased one-year readmission risk in THA and TKA patients. Treatment at large-sized hospitals was associated with a higher one-year readmission risk in TKA patients. CONCLUSIONS: The thirty-day and one-year readmission rates for implant-associated complications following THA or TKA in Austria are lower than reported in other countries, with similar risk factors and reasons for readmission. Considering that almost 20% of unplanned hospital readmissions following total joint arthroplasty are attributable to implant-associated complications, optimization of in-hospital and post-discharge medical care for these patients is warranted.

The effect of preoperative embolization on giant cell tumors of the bone localized in the iliosacral region of the pelvis.

INTRODUCTION: Giant cell tumors of the bone (GCTB) are aggressive neoplasms, with rare occurrences in the posterior pelvis and sacral area. Surgical challenges in this region include the inability to apply a tourniquet and limited cementation post-curettage due to proximity to neurovascular structures, leading to potential complications. This case-control study explores the impact of preoperative embolization on GCTB located in the iliosacral region. METHODS: Five surgeries (January-December 2021) for pelvic GCTB (3 sacrum, 2 posterior ilium) were performed on four patients. Diagnosis was confirmed through preoperative CT-guided biopsies. One surgery involved curettage with PMMA cement filling, while four surgeries had curettage without cavity filling. Preoperative embolization of the tumor feeding vessel occurred approximately 16 h before surgery in two cases. Denosumab treatment was not administered. RESULTS: Tumor volume, assessed by preoperative MRI, was comparable between patients with and without preoperative embolization (p = .14). Surgeries without embolization had a mean intraoperative blood loss of 3250 ml, erythrocyte transfusion volume of 1125 ml, and a mean surgical time of 114.5 min for two surgeries. Surgeries with preoperative embolization showed a mean intraoperative blood loss of 1850 ml, no erythrocyte transfusion requirement, and a mean surgical time of 68 min. CONCLUSION: Curettage of GCTB in the posterior pelvis and sacrum presents challenges, with significant intraoperative blood loss impacting surgical time and transfusion needs. Preoperative embolization may be beneficial in reducing blood loss during surgery in these cases.

Conventional vs. endoscopic-assisted curettage of benign bone tumours. An experimental study.

BACKGROUND: This experimental study aimed at directly comparing conventional and endoscopic-assisted curettage towards (1) amount of residual tumour tissue (RTT) and (2) differences between techniques regarding surgical time and surgeons' experience level. METHODS: Three orthopaedic surgeons (trainee, consultant, senior consultant) performed both conventional (4x each) and endoscopic-assisted curettages (4x each) on specifically prepared cortical-soft cancellous femur and tibia sawbone models. "Tumours" consisted of radio-opaque polyurethane-based foam injected into prepared holes. Pre- and postinterventional CT-scans were carried out and RTT assessed on CT-scans. For statistical analyses, percentage of RTT in relation to total lesion's volume was used. T-tests, Wilcoxon rank-sum tests, and Kruskal-Wallis tests were applied to assess differences between surgeons and surgical techniques regarding RTT and timing. RESULTS: Median overall RTT was 1% (IQR 1 - 4%). Endoscopic-assisted curettage was associated with lower amount of RTT (median, 1%, IQR 0 - 5%) compared to conventional curettage (median, 4%, IQR 0 - 15%, p = 0.024). Mean surgical time was prolonged with endoscopic-assisted (9.2 ± 2.9 min) versus conventional curettage (5.9 ± 2.0 min; p = 0.004). No significant difference in RTT amount (p = 0.571) or curetting time (p = 0.251) depending on surgeons' experience level was found. CONCLUSIONS: Endoscopic-assisted curettage appears superior to conventional curettage regarding complete tissue removal, yet at expenses of prolonged curetting time. In clinical practice, this procedure may be reserved for cases at high risk of recurrence (e.g. anatomy, histology).

Esophageal perforation with near fatal mediastinitis secondary to Th3 fracture.

A 74-year-old male patient was referred with signs of sepsis 5 days after having been diagnosed with a rib fracture following a fall out of bed. Novel hypodensities were visible on thoracic X­rays and laboratory tests revealed elevated inflammatory parameters. Subsequently performed thoracic computed tomography (CT) scan showed burst fracture of the 3rd thoracic vertebra, posttraumatic esophageal rupture at the same level and mediastinitis. Furthermore, marked degenerative changes of the spinal column (diffuse idiopathic skeletal hyperostosis) were present. The patient underwent emergency thoracotomy and esophagectomy. Gastric pull-up with esophagogastrostomy was postponed for 3 days. After 14 days on the intensive care unit (ICU) and 12 days of i.v. antibiotics, the patient was transferred to the general ward and 7 weeks after trauma the patient was infection-free without difficulties in swallowing. Up to the latest follow-up 41 months following injury, several endoscopic dilations with a bougie due to constrictions at the anastomosis have been performed. Similar to previous cases in the literature, esophageal injury was diagnosed delayed, with the patient already having developed severe complications. This extremely seldom injury should be suspected in young patients following high-energy trauma, but also in older patients after low-energy trauma but known degenerative changes of the vertebral column.

30-day and one-year readmission rate in 11,270 patients with surgical treatment for proximal femoral fractures across Austria.

Aims: Patients with proximal femoral fractures (PFFs) are often multimorbid, thus unplanned readmissions following surgery are common. We therefore aimed to analyze 30-day and one-year readmission rates, reasons for, and factors associated with, readmission risk in a cohort of patients with surgically treated PFFs across Austria. Methods: Data from 11,270 patients with PFFs, treated surgically (osteosyntheses, n = 6,435; endoprostheses, n = 4,835) at Austrian hospitals within a one-year period (January to December 2021) was retrieved from the Leistungsorientierte Krankenanstaltenfinanzierung (Achievement-Oriented Hospital Financing). The 30-day and one-year readmission rates were reported. Readmission risk for any complication, as well as general medicine-, internal medicine-, and surgery/injury-associated complications, and factors associated with readmissions, were investigated. Results: The 30-day and one-year readmission rates due to any complication were 15% and 47%, respectively. The 30-day readmission rate (p = 0.001) was higher in endoprosthesis than osteosynthesis patients; this was not the case for the one-year readmission rate (p = 0.138). Internal medicine- (n = 2,273 (20%)) and surgery/injury-associated complications (n = 1,612 (14%)) were the most common reason for one-year readmission. Regardless of the surgical procedure, male sex was significantly associated with higher readmission risk due to any, as well as internal medicine-associated, complication. Advanced age was significantly associated with higher readmission risk after osteosynthesis. In both cohorts, treatment at mid-sized hospitals was significantly associated with lower readmission risk due to any complication, while prolonged length of stay was associated with higher one-year readmission risks due to any complication, as well as internal-medicine associated complications. Conclusion: Future health policy decisions in Austria should focus on optimization of perioperative and post-discharge management of this vulnerable patient population.

Artificial intelligence large language model ChatGPT: is it a trustworthy and reliable source of information for sarcoma patients?

Introduction: Since its introduction in November 2022, the artificial intelligence large language model ChatGPT has taken the world by storm. Among other applications it can be used by patients as a source of information on diseases and their treatments. However, little is known about the quality of the sarcoma-related information ChatGPT provides. We therefore aimed at analyzing how sarcoma experts evaluate the quality of ChatGPT's responses on sarcoma-related inquiries and assess the bot's answers in specific evaluation metrics. Methods: The ChatGPT responses to a sample of 25 sarcoma-related questions (5 definitions, 9 general questions, and 11 treatment-related inquiries) were evaluated by 3 independent sarcoma experts. Each response was compared with authoritative resources and international guidelines and graded on 5 different metrics using a 5-point Likert scale: completeness, misleadingness, accuracy, being up-to-date, and appropriateness. This resulted in maximum 25 and minimum 5 points per answer, with higher scores indicating a higher response quality. Scores ≥21 points were rated as very good, between 16 and 20 as good, while scores ≤15 points were classified as poor (11-15) and very poor (≤10). Results: The median score that ChatGPT's answers achieved was 18.3 points (IQR, i.e., Inter-Quartile Range, 12.3-20.3 points). Six answers were classified as very good, 9 as good, while 5 answers each were rated as poor and very poor. The best scores were documented in the evaluation of how appropriate the response was for patients (median, 3.7 points; IQR, 2.5-4.2 points), which were significantly higher compared to the accuracy scores (median, 3.3 points; IQR, 2.0-4.2 points; p = 0.035). ChatGPT fared considerably worse with treatment-related questions, with only 45% of its responses classified as good or very good, compared to general questions (78% of responses good/very good) and definitions (60% of responses good/very good). Discussion: The answers ChatGPT provided on a rare disease, such as sarcoma, were found to be of very inconsistent quality, with some answers being classified as very good and others as very poor. Sarcoma physicians should be aware of the risks of misinformation that ChatGPT poses and advise their patients accordingly.

A comparative study assessing the efficacy and safety of radiofrequency ablation versus surgical treatment for osteoid osteoma: retrospective analysis in a single institution.

OBJECTIVE: We aim to evaluate the efficacy of CT-guided percutaneous radiofrequency ablation (RFA) and surgical treatment in osteoid osteoma (OO) treated at the Medical University of Graz. MATERIALS AND METHODS: In a single-institution study, we analysed data from January 2005 to January 2021 of patients with histological/radiological diagnosis of OO. CT and MRI scans were reviewed for typical findings. Means (with SD) and medians (with IQR) were reported for normally and non-normally distributed variables. Differences between groups were assessed using chi-squared tests and t-tests. RESULTS: One hundred nineteen patients (mean age: 21.6 ± 10.9 years; 63.9% males) with confirmed OO were retrospectively evaluated. 73 and 43 patients underwent RFA and surgery, respectively. In three cases, RFA combined with surgery was performed. Pre-intervention, 103 patients (88.8%) had undergone CT, and 101 had an MRI (87.1%). The nidus was confirmed in 82.5% of cases with CTs (85/103) and 63.4% with MRIs (64/101). The majority of nidi were located cortically (n = 96; 82.8%), most frequently in the femur (38 patients, 33.3%) with a median size of 8.0 mm (IQR: 5.0-12.0 mm). Median symptom duration before treatment was 6.0 (IQR: 4.0-13.0) months. The complication rate was 12.1% (14/116; 15.1% RFA vs. 7.0% surgery; p = 0.196). In total, 11.2% of patients had persistent symptoms after one week with clinical success rates of RFA and surgery, 86.3% and 90.7% (p = 0.647), respectively. CONCLUSION: Compared to surgical treatment, CT-guided percutaneous RFA is a safe, minimally invasive, reliable, and efficient treatment option for OO. CRITICAL RELEVANCE STATEMENT: This article critically assesses the diagnosis and treatment of osteoid osteoma, emphasising accurate imaging, and detailing a non-invasive option for effective management. KEY POINTS: • This study analyses 116 cases of OO at one institution, focusing on symptom persistence, recurrence in short-term follow-up, and complications in two study groups. • Surgery showed higher, though not statistically significant, success despite comparable symptom persistence; CT displayed typical OO features more than MRI, regardless of the intramedullary, cortical and subperiosteal location as well as the site of the affected bone. • CT-guided RFA is an effective therapeutic alternative for OO compared to surgical intervention. In case of atypical OO appearance, RFA is not the first-line treatment.

Long-term clinical and radiological outcome of a cementless titanium-coated total knee arthroplasty system.

INTRODUCTION: To ensure a high-quality standard, it is important to frequently evaluate different prostheses models to avoid prostheses with high failure rates. Thus, the aim of the study was to evaluate the long-term outcome of the uncemented titanium-coated total knee arthroplasty (TKA) system (Advanced Coated System (ACS) III, Implantcast, GERMANY). We hypothesized that the ACS III would have a similar performance as other cemented TKA systems. MATERIALS AND METHODS: A total of 540 ACS III mobile-bearing knee joint prostheses were implanted in 495 patients. The visual analogue scale (VAS) score, Tegner activity score (TAS), knee society score (KSS), Western Ontario and McMaster (WOMAC) score, and the Short Form 12 (SF-12) score for the evaluation of quality of life (QoL) were taken after at least 9 years of follow-up. In addition, we measured range of motion (ROM) and assessed potential sex differences. In addition, the survival analysis was calculated at a median follow-up of 16.7 years. RESULTS: At the final follow-up, 142 patients had died, and 38 had been lost to follow-up. The rate of revision-free implant survival at 16.7 years was 90.0% (95% CI 87.1-92.2%) and the rate of infection-free survival was 97.0% (IQR 95.2-98.2%). The reasons for revision surgery were aseptic loosening (32.9%), followed by infection (27.1%), inlay exchange (15.9%), and periprosthetic fractures (5.7%). At the clinical follow-up visit, the mean VAS score was 1.9 ± 1.9, the median TAS was 3 (IQR 2-4), and the mean KSS for pain and function were 83.5 ± 15.3 and 67.5 ± 25.2, respectively. The mean WOMAC score was 81.1 ± 14.9, and the median SF-12 scores for physical and mental health were 36.9 (IQR 29.8-45.1) and 55.8 (IQR 46.2-61.0), respectively. The mean knee flexion was 102.0° ± 15.4°. Male patients had better clinical outcome scores than female patients [SF-12 mental health score, p = 0.037; SF-12 physical health score, p = 0.032; KSS pain score (p < 0.001), and KSS functional score (p < 0.001)]. CONCLUSION: The ACS III TKA system is a suitable option for the treatment of end-stage osteoarthritis of the knee joint because of its adequate long-term survival. Our findings are in line with published data on similar TKA systems that have shown favourable clinical scores in males. LEVEL OF EVIDENCE: Level III-Retrospective cohort study.

Vancomycin Elution Kinetics of Four Antibiotic Carriers Used in Orthopaedic Surgery: In Vitro Study over 42 Days.

This study aimed to analyse and compare the vancomycin elution kinetics of four biodegradable, osteoconductive antibiotic carriers used in clinical practice within a 42-day in vitro setting. Carriers A and D already contained vancomycin (1.1 g and 0.247 g), whereas carriers B and C were mixed with vancomycin according to the manufacturer's recommendations (B: 0.83 g and C: 0.305 g). At nine time points, 50% (4.5 mL) of the elution sample was removed and substituted with the same amount of PBS. Probes were analysed with a kinetic microparticle immunoassay. Time-dependent changes in vancomycin concentrations for each carrier and differences between carriers were analysed. Mean initial antibiotic levels were highest for carrier A (37.5 mg/mL) and lowest for carrier B (5.4 mg/mL). We observed time-dependent, strongly negative linear elution kinetics for carriers A (-0.835; p < 0.001), C (-0.793; p < 0.001), and D (-0.853; p < 0.001). Vancomycin concentrations increased from 48 h to 7 d and dropped thereafter in carriers C and D whilst constantly decreasing at any time point for carrier A. Carrier B showed a shallower decrease. Mean antibiotics levels at 42 d were 1.5 mg/mL, 2.6 mg/mL, 0.1 mg/mL, and 0.1 mg/mL for carriers A, B, C, and D. Differences in mean initial and final vancomycin concentrations for carrier A were significantly larger in comparison to C (p = 0.040). A carrier consisting of allogenic bone chips showed the highest vancomycin-to-carrier ratio and the largest elution over the study period. Whilst vancomycin concentrations were still measurable at 42 days for all carriers, carrier A provided a higher drug-to-carrier ratio and a more consistent antibiotic-releasing profile.

Effect of radiotherapy on local recurrence, distant metastasis and overall survival in 1200 extremity soft tissue sarcoma patients. Retrospective analysis using IPTW-adjusted models.

BACKGROUND AND PURPOSE: Neoadjuvant (NRTX) and adjuvant radiotherapy (ARTX) reduce local recurrence (LR) risk in extremity soft tissue sarcoma (eSTS), yet their impact on distant metastasis (DM) and overall survival (OS) is less well defined. This study aimed at analysing the influence of NRTX/ARTX on all three endpoints using a retrospective, multicentre eSTS cohort. MATERIALS AND METHODS: 1200 patients (mean age: 60.7 ± 16.8 years; 44.4 % females) were retrospectively included, treated with limb sparing surgery and curative intent for localised, high grade (G2/3) eSTS. 194 (16.2 %), 790 (65.8 %), and 216 (18.0 %) patients had received NRTX, ARTX and no RTX, respectively. For the resulting three groups (no RTX vs. NRTX, no RTX vs. ARTX, NRTX vs. ARTX) Fine&Gray models for LR and DM, and Cox-regression models for OS were calculated, with IPTW-modelling adjusting for imbalances between groups. RESULTS: In the IPTW-adjusted analysis, NRTX was associated with lower LR-risk in comparison to no RTX (SHR [subhazard ratio]: 0.236; p = 0.003), whilst no impact on DM-risk (p = 0.576) or OS (p = 1.000) was found. IPTW-weighted analysis for no RTX vs. ARTX revealed a significant positive association between ARTX and lower LR-risk (SHR: 0.479, p = 0.003), but again no impact on DM-risk (p = 0.363) or OS (p = 0.534). IPTW-weighted model for NRTX vs. ARTX showed significantly lower LR-risk for NRTX (SHR for ARTX: 3.433; p = 0.003) but no difference regarding DM-risk (p = 1.000) or OS (p = 0.639). CONCLUSION: NRTX and ARTX are associated with lower LR-risk, but do not seem to affect DM-risk or OS. NRTX may be favoured over ARTX as our results indicate better local control rates.

The Enigma of Atypical Cartilaginous Tumors: Surgery or Surveillance?

During the last 20 years, the treatment of atypical cartilaginous tumors (ACTs) of the long bones has undergone a dramatic change: while these formerly called chondrosarcomas G1 previously led to wide resections and big reconstructions with megaprostheses, today, the use curettage of the lesions and filling the defect e [...].

Effect of Local Adjuvants Following Curettage of Benign and Intermediate Tumours of Bone: A Systematic Review of the Literature.

Local adjuvants are used upon intralesional resection of benign/intermediate bone tumours, aiming at reducing the local recurrence (LR) rate. However, it is under debate whether, when and which local adjuvants should be used. This PRISMA-guideline based systematic review aimed to analyse studies reporting on the role of adjuvants in benign/intermediate bone tumours. All original articles published between January 1995 and April 2020 were potentially eligible. Of 344 studies identified, 58 met the final inclusion criteria and were further analysed. Articles were screened for adjuvant and tumour type, follow-up period, surgical treatment, and development of LR. Differences in LR rates were analysed using chi-squared tests. Altogether, 3316 cases (10 different tumour entities) were analysed. Overall, 32 different therapeutic approaches were identified. The most common were curettage combined with high-speed burr (n = 774; 23.3%) and high-speed burr only (n = 620; 18.7%). The LR rate for studies with a minimum follow-up of 24 months (n = 30; 51.7%) was 12.5% (185/1483), with the highest rate found in GCT (16.7%; 144/861). In comparison to a combination of curettage, any adjuvant and PMMA, the sole application of curettage and high-speed burr (p = 0.015) reduced the LR rate in GCT. The overall complication rate was 9.6% (263/2732), which was most commonly attributable to postoperative fracture (n = 68) and osteoarthritis of an adjacent joint during follow-up (n = 62). A variety of adjuvants treatment options are reported in the literature. However, the most important step remains to be thorough curettage, ideally combined with high-speed burring.

Spatial tumour gene signature discriminates neoplastic from non-neoplastic compartments in colon cancer: unravelling predictive biomarkers for relapse.

BACKGROUND: Opting for or against the administration of adjuvant chemotherapy in therapeutic management of stage II colon cancer remains challenging. Several studies report few survival benefits for patients treated with adjuvant therapy and additionally revealing potential side effects of overtreatment, including unnecessary exposure to chemotherapy-induced toxicities and reduced quality of life. Predictive biomarkers are urgently needed. We, therefore, hypothesise that the spatial tissue composition of relapsed and non-relapsed colon cancer stage II patients reveals relevant biomarkers. METHODS: The spatial tissue composition of stage II colon cancer patients was examined by a novel spatial transcriptomics technology with sub-cellular resolution, namely in situ sequencing. A panel of 176 genes investigating specific cancer-associated processes such as apoptosis, proliferation, angiogenesis, stemness, oxidative stress, hypoxia, invasion and components of the tumour microenvironment was designed to examine differentially expressed genes in tissue of relapsed versus non-relapsed patients. Therefore, FFPE slides of 10 colon cancer stage II patients either classified as relapsed (5 patients) or non-relapsed (5 patients) were in situ sequenced and computationally analysed. RESULTS: We identified a tumour gene signature that enables the subclassification of tissue into neoplastic and non-neoplastic compartments based on spatial expression patterns obtained through in situ sequencing. We developed a computational tool called Genes-To-Count (GTC), which automates the quantification of in situ signals, accurately mapping their position onto the spatial tissue map and automatically identifies neoplastic and non-neoplastic tissue compartments. The GTC tool was used to quantify gene expression of biological processes upregulated within the neoplastic tissue in comparison to non-neoplastic tissue and within relapsed versus non-relapsed stage II colon patients. Three differentially expressed genes (FGFR2, MMP11 and OTOP2) in the neoplastic tissue compartments of relapsed patients in comparison to non-relapsed patients were identified predicting recurrence in stage II colon cancer. CONCLUSIONS: In depth spatial in situ sequencing showed potential to provide a deeper understanding of the underlying mechanisms involved in the recurrence of disease and revealed novel potential predictive biomarkers for disease relapse in colon cancer stage II patients. Our open-access GTC-tool allowed us to accurately capture the tumour compartment and quantify spatial gene expression in colon cancer tissue.

More help than harm: surgery for metastatic spinal cord compression is associated with more favorable overall survival within a propensity score analysis.

PURPOSE: Indication for surgical decompression in metastatic spinal cord compression (MSCC) is often based on prognostic scores such as the modified Bauer score (mBs), with favorable prognosis suggestive of surgery and poor prognosis of non-surgical management. This study aimed to clarify if (1) surgery may directly affect overall survival (OS) aside from short-term neurologic outcome, (2) explore whether selected patient subgroups with poor mBs might still benefit from surgery, and (3) gauge putative adverse effects of surgery on short-term oncologic outcomes. METHODS: Single-center propensity score analyses with inverse-probability-of-treatment-weights (IPTW) of OS and short-term neurologic outcomes in MSCC patients treated with or without surgery between 2007 and 2020. RESULTS: Among 398 patients with MSCC, 194 (49%) underwent surgery. During a median follow-up of 5.8 years, 355 patients (89%) died. MBs was the most important predictor for spine surgery (p < 0.0001) and the strongest predictor of favorable OS (p < 0.0001). Surgery was associated with improved OS after accounting for selection bias with the IPTW method (p = 0.021) and emerged as the strongest determinant of short-term neurological improvement (p < 0.0001). Exploratory analyses delineated a subgroup of patients with an mBs of 1 point who still benefited from surgery, and surgery did not result in a higher risk of short-term oncologic disease progression. CONCLUSION: This propensity score analysis corroborates the concept that spine surgery for MSCC associates with more favorable neurological and OS outcomes. Selected patients with poor prognosis might also benefit from surgery, suggesting that even those with low mBs may be considered for this intervention.

Prevalence and characteristics of benign cartilaginous tumours of the knee joint as identified on MRI scans.

BACKGROUND: Enchondromas (EC) and atypical cartilaginous tumours (ACT) of the knee joint represent benign/intermediate chondromatous neoplasms of the bone that are most commonly discovered incidentally. Based on small to intermediate-sized cohorts, the prevalence of cartilaginous tumours of the knee as visible in MRI is estimated at 0.2-2.9%. This study aimed at verifying/challenging these numbers via retrospective examination of a larger, uniform patient cohort. METHODS: Between 01.01.2007 and 01.03.2020, 44,762 patients had received an MRI of the knee for any indication at a radiologic centre. Of these, 697 patients presented with MRI reports positive for cartilaginous lesions. In a three-step workflow, 46 patients were excluded by a trained co-author, a radiologist and an orthopaedic oncologist, as wrongly being diagnosed for a cartilage tumour. RESULTS: Of 44,762 patients, 651 presented with at least one EC/ACT indicating a prevalence of 1.45% for benign/intermediate cartilaginous tumours of the knee joint (EC: 1.4%; ACTs: 0.05%). As 21 patients showed 2 chondromatous lesions, altogether 672 tumours (650 ECs [96.7%] and 22 ACTs [3.3%]) could be analysed in terms of tumour characteristics: With a mean size of 1.6 ± 1.1 cm, most lesions were located in the distal femur (72.9%), in the metaphysis of the respective bone (58.9%) and centrally in the medullary canal (57.4%). CONCLUSIONS: This study revealed an overall prevalence of 1.45% for cartilage lesions around the knee joint. Whilst a constant increase in prevalence was found for ECs over 13.2 years, prevalence remained constant for ACTs.

Clinical and functional outcome after partial or total claviculectomy without reconstruction for oncologic causes.

BACKGROUND: To achieve clear margins in rare malignant clavicular neoplasms, claviculectomy may become necessary. This study aimed to review clinical, functional, and oncologic outcomes following partial or total claviculectomy without reconstruction. METHODS: This study retrospectively included 15 patients from 2 tertiary sarcoma centers (mean age, 42.6 ± 20.3 years; 66.7% male patients). The median length of clinical and oncologic follow-up was 48.0 months (interquartile range [IQR], 24.0-83.5 months). Functional follow-up (Musculoskeletal Tumor Society score and QuickDASH score [short version of the Disabilities of the Arm, Shoulder and Hand questionnaire]) was available in 9 patients at a median of 36.0 months (IQR, 20.0-100.0 months). RESULTS: Of the 15 patients, 7 underwent total claviculectomy; 5, partial lateral claviculectomy; and 3, partial medial claviculectomy. No postoperative complications emerged. The median Musculoskeletal Tumor Society and QuickDASH scores at latest follow-up amounted to 26.0 points (IQR, 24.0-29.0 points) and 18.0 points (IQR, 11.0-22.0 points), respectively. Notably, scores tended to be lower in patients who underwent total claviculectomy (n = 2) in comparison to partial claviculectomy (n = 7). CONCLUSION: Satisfactory clinical and functional results can be achieved following partial or total claviculectomy without reconstruction, with a low complication rate and acceptable mid- to long-term function.

Femoral Anteversion in Total Hip Arthroplasty: Retrospective Comparison of Short- and Straight-Stem Models Using CT Scans.

Data on reconstruction of the femoral anteversion (FA) and the center of rotation after total hip arthroplasty (THA) are rare. We aimed to answer whether a short-stem fixation enables improved anatomical reconstruction of the FA compared to a straight-stem. METHODS: One hundred and thirty patients who underwent short- (n = 89, group A, prospective) or straight-stem THA (n = 41, group B, retrospective) were included. CT scans of the hip, knee, and ankle were performed pre- and postoperatively in group A and in group B during the last follow-up. Femoral torsion was determined using three-dimensional models. RESULTS: The mean preoperative FA was 22.4° ± 11.0°, and the mean postoperative FA was 23.4° ± 10.1°. The relative difference was -0.8° ± 8°, and the absolute difference was 6.4° ± 4.9°. Gender analysis revealed significant differences in preoperative FA between female (f) and male (m) patients (28.1° ± 11.2° (f) vs. 18.4° ± 8.3° (m); p > 0.001) as well as in postoperative FA (26.7° ± 23.5° (f) vs. 21.0° ± 9.7° (m); p < 0.007) in group A. Postoperative FA was higher in group A (mean 6.8°; 23.9° ± 10.1° (f) vs. 16.6° ± 8.6° (m); p < 0.001). CONCLUSIONS: The study's findings suggest that short-stem THA leads to improved anatomical FA reconstruction; however, a substantial postoperative gender-related FA difference was detectable, which may warrant consideration by surgeons when determining the final stem anteversion. It should be noted that the impact of the postoperative gender-related FA difference on clinical outcomes is not entirely clear, and further research is warranted to elucidate this relationship.