Patient-specific guides for consistently achieving R0 bone margins after resection of primary malignant bone tumors of the pelvis.

AIMS: Primary malignant bone tumor of the pelvis is an uncommon lesion, the resection of which via freehand osteotomy is subject to inaccuracy due to its three-dimensional anatomy. Patient-Specific Guides (PSG), also called Patient-Specific Instruments (PSI) are essential to ensure surgical planning and resection adequacy. Our aim was to assess their use and effectiveness. METHODS: A monocentric retrospective study was conducted on 42 adult patients who underwent PSG-based resection of a primary malignant bone tumor of the pelvis. The primary outcome was the proportion of R0 bone margins. The secondary outcomes were the proportion of overall R0 margins, considering soft-tissue resection, the cumulative incidence of local recurrence, and the time of production for the guides. A comparison to a previous series at our institution was performed regarding histological margins. RESULTS: Using PSGs, 100% R0 safe bone margin was achieved, and 88% overall R0 margin due to soft-tissue resection being contaminated, while the comparison to the previous series showed only 80% of R0 safe bone margin. The cumulative incidences of local recurrence were 10% (95% CI: 4-20%) at one year, 15% (95% CI: 6-27%) at two years, and 19% (95% CI: 8-33%) at five years. The median overall duration of the fabrication process of the guide was 35 days (Q1-Q3: 26-47) from the first contact to the surgery date. CONCLUSIONS: Patient-Specific Guides can provide a reproducible safe bony margin.

AtoG: A simple score to predict complications and death after hip fractures, in line with the comprehensive geriatric assessment.

INTRODUCTION: Proximal Femur Fractures (PFFs) are a significant public health issue and occur in the context of global frailty and aging. Recent literature identifies new patient-related prognostic factors that focus on socioeconomic environment, patient well-being, or nutrition status. Specific scores have been developed, but in most cases, they fail to be in line with the comprehensive geriatric assessment, or do not assess the newly identified prognostic factors, contain multitude collinearities, or are too complex to be used in the daily practice. Hypothesis A comprehensive score with equal representation of the patient's dimensions does at least as good as the Charlson score (CCI), to predict complications and mortality. OBJECTIVE: To develop a new comprehensive prognostic score, predicting inpatient complications and mortality up to 5-year after PFF. MATERIAL AND METHODS: The patients treated surgically for PFF on a native hip, between 2005 and 2017 were selected from a French national database. The variables were the gender, age, the type of treatment (osteosynthesis or arthroplasty), and the CCI. The outcomes were the medical and surgical complications as inpatient and the mortality (up to 5-year). Variables were grouped into dimensions with similar clinical significance, using a Principal Component Analysis, for instance, bedsores and malnutrition. The dimensions were tested for 90-day mortality and complications, in regressions models. Two scores were derived from the coefficients: SCOREpond (strict ponderation), and SCORE (with loose ponderation: 1 point/risk factors, -1 point/protective factors). Calibration, discrimination (ROC curves with Area Under Curves AUC), and cross-validation were assessed for SCOREpond, SCORE, and CCI. RESULTS: Analyses were performed on 7756 fractures. The factorial analysis identified seven dimensions: age; brain-related conditions (including dementia): 1738/7756; severe chronic conditions (for instance, organ failures) 914/7756; undernutrition: 764/7756; environment, including social issues or housing difficulties: 659/7756; associated trauma: 814/7756; and gender. The seven dimensions were selected for the prognostic score named AtoG (ABCDEFG, standing for Age, Brain, Comorbidities, unDernutrition, Environment, other Fractures, Gender). The median survival rate was 50.8 months 95% CI [49-53]. Anaemia and urologic complications were the most prevalent medical complications (1674/7756, 21%, and 1109/7756, 14.2%). A total of 149/7756 patients (1.9%) developed a mechanical inpatient complication (fractures or dislocations), with a slightly higher risk for arthroplasties. The AUCs were 0.69, 0.68, and 0.67 for AtoGpond, AtoG, and CCI, respectively, for 90-day mortality, and 0.64, 0.63, and 0.56 for complications. Compared to patients with AtoG=0, Hazard Ratios for 90-day mortality were 2.3 95% CI [1.7-2.9], 4.2 95% CI [3.1-5.4], 6 95% CI [4.5-8.1], 8.3 95% CI [6.5-12.9], and 13.7 95% CI [8-24], from AtoG=1 to AtoG≥5, respectively (p<10-4); the 90-day survival decreased by 5%/point, roughly. The sur-risk of mortality associated with AtoG was up to 5-year: HR=1.51 (95% CI [1.46-1.55], p<10-4). Compared to AtoG=0, from AtoG=1 to AtoG≥5, the pooled Odd Ratios were 1.14 95% CI [1.06-1.2], 1.53 95% CI [1.4-1.7], 2.17 95% CI [1.9-2.4], 2.9 95% CI [2.4-3.4], and 4.9 95% CI [3.3-7.4] for any complication (p<10-4). CONCLUSION: AtoG is a multidimensional score in line with the concept of comprehensive geriatric assessment. It had good discrimination and performance in predicting 90-day mortality and complications. Performances were as good as CCI for 90-day mortality, and better than it for the complications. LEVEL OF PROOF: IV; retrospective cohort study.

Periosteal chondroblastoma of the femoral neck: two cases and a review of the literature.

Chondroblastoma is a rare benign cartilaginous tumor mostly confined to the epiphyses and apophyses. Cases outside the epiphyseal region are exceedingly rare. Extramedullary chondroblastomas are exceptional; to our knowledge, only two cases qualified as "periosteal chondroblastoma" have been described in the literature. We report two cases of metaphyseal periosteal chondroblastoma both located on the inferior surface of the femoral neck. Both cases were paucicellular with an unusual dense sclerotic reaction. The diagnosis of chondroblastoma was supported by the expression of histone 3.3, K36M mutant in tumor cells.

What to improve: Results of fixed-hinge knee endoprosthesis reconstructions over 40 years in a single tumor center.

INTRODUCTION: Over the past decades, numerous structural changes in implants, medical treatments, and surgical techniques have been made for Malignant Bone Tumors (MBT) around the knee. However, the overall care improvement is still unclear. The method is crucial when analyzing outcomes in surveys involving tumors, and a thorough assessment of the mortality is mandatory because death acts as competing event. The aims of this study were: 1) a comprehensive and longitudinal assessment of the revisions with an extensive follow-up and adequate methods; 2) a complete mortality review to consider competing risks. HYPOTHESIS: The hypothesis was that some prosthesis's structural improvements were made while the surgical toll increased as well as an improvement of mortality was also expected. MATERIAL AND METHODS: Analyses were performed on 248 patients with MBT (mean follow-up was 8.7 years, surgeries between 1972 and 2017). Three prosthesis models were successively used over time: 120 Guepar (older model), 42 Tornier, and 86 Stanmore (more recent model). The primary outcome was the assessment of revisions sorted out according to Henderson: type-1 soft-tissue failures or instability, type-2 aseptic loosening, type-3 structural failures, type-4 periprosthetic infections, type-5 tumoral progression. Death and amputations were considered as competing events. An extensive assessment of mortality was performed by merging the dataset with the French register of Deaths (INSEE). Cumulative probabilities were computed at 2, 5, 10, and 15 years and compared with Gray's tests. RESULTS: The overall 5-year survival was, 80% (95% CI: 73-87) for Guepar, 69% (95% CI: 56-84) for Tornier, and 71% (95% CI: 62-82) for Stanmore (p=0.4). The 5-year cumulative risks for type-1 were 5% (95% CI: 1-9), 9% (95% CI: 0-18), and 17% (95% CI: 9-25) for Guepar, Tornier, and Stanmore, respectively (p=0.01). The 15-year cumulative risks for type-2 were 22% (95% CI: 15-39), 8% (95% CI: 0-17) and 8% (95% CI: 2-14) for Guepar, Tornier, and Stanmore, respectively (p=0.10). Ten patients had an implant failure, nine Guepar, and one Tornier. The 5-year cumulative risks for type-4 were 7% (95% CI: 2-12), 19% (95% CI: 7-31), and 12% (95% CI: 5-18) for Guepar, Tornier, and Stanmore, respectively (p=0.08). There were 29 tumoral progressions; the 15-year risks were 16% (95% CI: 2-22), 2% (95% CI: 0-7%), and 12% (95% CI: 4-19%) for Guepar, Tornier, and Stanmore, respectively (p=0.08). No difference whatsoever was found between the proximal tibial and distal femur. CONCLUSION: There were some improvements in prosthesis design (forged steel instead of cast steel) and probably also in cemented stem fixation, but not in prosthetic joint infection and local recurrence over forty years. The overall mortality did not change significantly over the last 40 years amongst this specific cohort of patients who benefited from a hinge reconstruction prosthesis. LEVEL OF EVIDENCE: III; comparative case series with sensibility analysis.

Hip fractures after 60 years of age in France in 2005-2017: Nationwide sample of statutory-health-insurance beneficiaries.

BACKGROUND: Proximal femoral factures (PFFs) constitute a heavy medical, social, and economic burden. Overall, orthopaedic conditions vary widely in France regarding the patients involved and treatments applied. For PFFs specifically, data are limited. Moreover, the ongoing expansion of geriatric orthopaedics holds promise for improving overall postoperative survival. The objectives of this retrospective study of a nationwide French database were: 1) to describe the pathway of patients with PFFs regarding access to care, healthcare institutions involved, and times to management; 2) to look for associations linking these parameters to post-operative mortality. HYPOTHESIS: Across France, variations exist in healthcare service availability and time to management for patients with PFFs. MATERIAL AND METHODS: A retrospective analysis of data in a de-identified representative sample of statutory-health-insurance beneficiaries in France (Échantillon généraliste des bénéficiaires, EGB, containing data for 1/97 beneficiaries) was conducted. All patients older than 60 years of age who were managed for PFFs between 2005 and 2017 were included. The following data were collected for each patient: age, management method, Charlson's Comorbidity Index (CCI), home-to-hospital distance by road, and type of hospital (public, non-profit private, or for-profit private), and time to surgery were collected. The study outcomes were the incidence of PFF, mortality during the first postoperative year, changes in mortality between 2005 and 2017, and prognostic factors. RESULTS: In total 8026 fractures were included. The 7561 patients had a median age of 83.8 years and a mean CCI of 4.6; both parameters increased steadily over time, by 0.18 years and 0.06 points per year, respectively (p<10-4 for both comparisons). Management was by total hip replacement in 3299 cases and internal fixation in 4262 cases; this information was not available for 465 fractures. The overall incidence increased from 90/100,000 in 2008 to 116/100,000 in 2017 (p=0.03). Of the 8026 fractures, 5865 (73.1%) were managed in public hospitals (and this proportion increased significantly over time), 1629 (20.3%) in non-profit private hospitals (decrease over time), and 264 (3.3%) in for-profit private hospitals. The home-to-hospital distance ranged from 7.5 to 38.5km and increased over time by 0.26km/year (95% confidence interval [95%CI]: 0.15-0.38) (p<10-4). Median time to surgery was 1 day [1-3 days], with no significant difference across hospital types. Mortality rates at 90 days and 1 year were 10.5% (843/8026) and 20.8% (1673/8026), respectively. Two factors were significantly associated with day-90 mortality: the CCI (hazard ratio [HR], 1.087 [95%CI: 1.07-1.10] [p<10-4]) and time to surgery>1 day (HR 1.35 [95%CI: 1.15-1.50] [p<0.0001]). Day-90 mortality decreased significantly from 2005 to 2017 (HR 0.95 [95%CI: 0.92-0.97] [p<10-4]), with no centre effect. CONCLUSION: The management of PFF in patients older than 60 varied widely across France. Time to surgery longer than 1 day was a major adverse prognostic factor whose effects persisted throughout the first year. This factor was present in over half the patients. Day-90 mortality decreased significantly from 2005 to 2017 despite increases in age and comorbidities. LEVEL OF EVIDENCE: IV Retrospective cohort study.

Diagnosis and management of METS-Stanmore Morse taper failure.

We describe clinical semiology in 6 cases of METS-Stanmore distal femoral Morse taper impaction failure: from obvious forms with intraprosthetic dislocation to chronic forms with less obvious symptoms: instability, piston sensation, rotational disorder in gait. The diagnostic procedure in chronic forms is described, notably with dynamic examination under fluoroscopy. Reduction and re-impaction by external maneuver can be attempted; in case of failure or of any suspicion of taper disassembly, the 2 modular implant components have to be replaced. Finally, we provide a review of the literature on this rare but serious complication. LEVEL OF EVIDENCE: IV.

Preoperative Arterial Embolization of Musculoskeletal Tumors: A Tertiary Center Experience.

The purpose of this study was to report the effectiveness of preoperative transcatheter arterial embolization (TAE) of musculoskeletal tumors in terms of blood loss and functional outcomes. Patients who underwent preoperative TAE of hypervascular musculoskeletal tumors between January 2018 and December 2021 were retrospectively included. The patients' characteristics, TAE procedure details, degree of post-TAE devascularization, surgical outcomes in terms of red blood cell transfusion and functional results were collected. The degree of devascularization was compared between patients who had peri-operative transfusion and those who did not. Thirty-one patients were included. The 31 TAE procedures led to complete (58%) or near-complete (42%) tumor devascularization. Twenty-two patients (71%) had no blood transfusion during surgery. Nine patients (29%) had a blood transfusion, with a median number of red blood cell packs of three (q1, 2; q3, 4; range: 1-4). Eight patients (27%) had complete improvement of the initial musculoskeletal symptoms at the end of the follow-up, 15 (50%) had partially satisfying improvement, 4 (13%) had partially unsatisfying improvement and 3 (10%) had no improvement. Our study suggests that preoperative TAE of hypervascular musculoskeletal tumors allowed for bloodless surgery in 71% of patients and minimal transfusion needs for the remaining 29%.

Surgical site infection after pelvic bone and soft tissue sarcoma resection: Risk factors, microbiology, and impact of extended postoperative antibiotic prophylaxis.

BACKGROUND: Pelvic bone and/or soft tissue sarcoma removal surgeries are associated with a high rate of surgical site infection (SSI). The recommended antibiotic prophylaxis (ABP) duration is 24-48 h. We aimed to assess the impact of extended ABP (5 days) on the SSI rate and describe the microbiology of SSI in bone and/or soft tissue pelvic sarcomas. METHODS: We retrospectively included all consecutive patients who underwent pelvic bone and/or soft tissue sarcoma removal surgery between January 2010 and June 2020. RESULTS: We analyzed 146 patients with pelvic bone (45, 31%) or soft tissue (101, 69%). Sixty patients (41%) developed SSI. SSI occurred in 13/28 (46.4%) in the extended ABP group versus 47/118 (39.8%) in the standard group (p = 0.53). In multivariable analysis, risk factors for SSI were surgery duration (OR: 1.94 [1.41-2.92] per h), stay in postoperative ICU for more than 2 days (12.0 [2.8-61.3]), and shred or autologous skin flap (39.3 [5.8-409.5]). Extended ABP was not associated with SSI. SSI were mainly polymicrobial with Enterobacterales (57.4%) and Enterococcus (45%). CONCLUSIONS AND DISCUSSION: Pelvic bone and/or soft tissue sarcoma removal surgery is highly prone to postoperative infection. Extending the ABP to 5 days does not reduce the level of SSI.

Biology and Management of High-Grade Chondrosarcoma: An Update on Targets and Treatment Options.

This review provides an overview of histopathology, clinical presentation, molecular pathways, and potential new systemic treatments of high-grade chondrosarcomas (CS), including grade 2−3 conventional, dedifferentiated, and mesenchymal CS. The diagnosis of CS combines radiological and histological data in conjunction with patient clinical presentations. Conventional CS is the most frequent subtype of CS (85%) and represents about 25% of primary bone tumors in adults; they can be categorized according to their bone location into central, peripheral, and periosteal chondrosarcomas. Central and peripheral CS differ at the molecular level with either IDH1/2 mutations or EXT1/2 mutations, respectively. CDKN2A/B deletions are also frequent in conventional CS, as well as COL2A1 mutations. Dedifferentiated CS develops when low-grade conventional CS transforms into a high-grade sarcoma and most frequently exhibits features of osteosarcoma, fibrosarcoma, or undifferentiated pleomorphic sarcoma. Their molecular characteristics are similar to conventional CS. Mesenchymal CS is a totally different pathological entity exhibiting recurrent translocations. Their clinical presentation and management are different too. The standard treatment of CSs is wide en-bloc resection. CS are relatively radiotherapy resistant; therefore, doses >60 Gy are needed in an attempt to achieve local control in unresectable tumors. Chemotherapy is possibly effective in mesenchymal chondrosarcoma and is of uncertain value in dedifferentiated chondrosarcoma. Due to resistance to standard anticancer agents, the prognosis is poor in patients with metastatic or unresectable chondrosarcomas. Recently, the refined characterization of the molecular profile, as well as the development of new treatments, allow new therapeutic options for these rare tumors. The efficiency of IDH1 inhibitors in other malignancies suggests that these inhibitors will be part of IDH1/2 mutated conventional CS management soon. Other treatment approaches, such as PIK3-AKT-mTOR inhibitors, cell cycle inhibitors, and epigenetic or immune modulators based on improving our understanding of CS molecular biology, are emerging.

Prognostic factors of the synovial sarcoma of the extremities: imaging does matter.

OBJECTIVES: Synovial sarcomas (SS) of the extremities are rare soft tissue sarcomas that are more common in young adults. We deciphered the imaging phenotype of SS with the aim to determine if imaging could provide an incremental value to currently known prognostic factors (PF)-age and histological grade-to predict long-term overall survival (OS). METHODS: This retrospective multicenter study included consecutive pediatric and adult patients with synovial sarcomas of the extremities from December 2002 to August 2020. Inclusion criteria were (i) a follow-up greater than 5 years and (ii) available pre-therapeutic MRI. A subset analysis included MRI and CT-scan. Clinical, pathological, and imaging variables were collected in all patients. The primary endpoint was to evaluate the association of these variables with OS using univariate and multivariate Cox regressions. RESULTS: Out of 428 patients screened for eligibility, 98 patients (mean age: 37.1 ± 15.2 years) were included (MRI: n = 98/98, CT scan: n = 34/98; 35%). The median OS was 75.25 months (IQR = 55.50-109.12) and thirty-six patients (n = 36/98;37%) died during follow-up. The recurrence rate was 12.2% (n =12/98). SS lesions were mostly grade 2 (57/98; 58%). On MRI, SS had a mean long-axis diameter of 67.5 ± 38.3 mm. On CT scan, 44% (15/34) were calcified. Grade (hazard ratio [HR] = 2.71; 95%CI = 1.30-5.66; p = 0.008), size of the lesions evaluated on MRI (HR = 1.02; 95% CI = 1.01-1.03; p < 0.001), and calcifications on CT scan (HR = 0.10; 95% CI = 0.02-0.50; p = 0.005) were independent PF of OS. CONCLUSIONS: This study demonstrated that imaging biomarkers can be used to predict long-term outcome in patients with SS. Strikingly, the presence of calcifications on CT scan is associated with favorable outcome and provides an incremental value over existing PF such as age, grade, and size. KEY POINTS: • Beyond its diagnostic value, MRI is a pre-operative prognostic tool in synovial sarcomas of the extremities since the size of the lesion is an important prognostic factor. • Calcifications on CT scans are independently and significantly associated with prolonged overall survival.

Artificial intelligence in musculoskeletal oncology imaging: A critical review of current applications.

Artificial intelligence (AI) is increasingly being studied in musculoskeletal oncology imaging. AI has been applied to both primary and secondary bone tumors and assessed for various predictive tasks that include detection, segmentation, classification, and prognosis. Still, in the field of clinical research, further efforts are needed to improve AI reproducibility and reach an acceptable level of evidence in musculoskeletal oncology. This review describes the basic principles of the most common AI techniques, including machine learning, deep learning and radiomics. Then, recent developments and current results of AI in the field of musculoskeletal oncology are presented. Finally, limitations and future perspectives of AI in this field are discussed.

Performance of Sonoelastography for predicting malignancy in soft tissue.

BACKGROUND: Separating benign from malignant soft-tissue masses often requires a biopsy. The objective of this study was to assess whether shear-wave elastography (SWE) helped to separate benign from malignant soft-tissue masses. METHODS: In 2015-2016, we prospectively included patients with soft-tissue masses deemed by our multidisciplinary sarcoma board to require a diagnostic biopsy. All patients underwent ultrasonography (US) followed by SWE to measure elasticity. We compared benign and malignant tumors, overall and after separating tumors with vs. without a fatty component. The biopsy findings, and surgical-specimen histology when available, served as the reference standard. RESULTS: We included 136 patients, 99 with non-fatty and 37 with fatty soft-tissue masses. Mean elasticity and tumor-to-fat elasticity ratio (T/F) values were significantly lower for the benign than the malignant soft-tissue masses in the overall cohort (30.9 vs. 50.0 kilopascals (kPa), P = 0.03; and 2.55 vs. 4.30, P = 0.046) and in the non-fatty subgroup (37.8 ± 31.9 vs. 58.9 ± 39.1 kPa, P = 0.049 and 2.89 ± 5.25 vs. 5.07 ± 5.41, P = 0.046). Data for fatty tumors were non relevant due to lack of conclusive results. By receiver operating characteristics curve analysis, a T/F cutoff of 3.5 had 46% sensitivity and 84% specificity for separating benign and malignant soft-tissue masses. CONCLUSIONS: SWE had good specificity and poor sensitivity for separating benign from malignant soft-tissue masses.

Netrin-1 Secreted by Human Osteoarthritic Articular Chondrocytes Promotes Angiogenesis in Vitro.

OBJECTIVE: Netrin-1 expression in articular cartilage is correlated with osteoarthritic changes. We aimed to investigate the contribution of Netrin-1 secreted by human osteoarthritic articular chondrocytes to angiogenesis process in vitro. DESIGN: Human articular chondrocytes were extracted from non-osteoarthritic (n = 10) and osteoarthritic (n = 22) joints obtained from surgical specimens and incubated for 24 hours. Medium conditioned by non-osteoarthritic and osteoarthritic articular chondrocytes were collected. Human umbilical vein endothelial cells (HUVEC) were treated with control and conditioned medium and assessed using assays for cell adherence, migration, and tube formation. Netrin-1 expression and secretion was compared between non-osteoarthritic and osteoarthritic chondrocytes by qPCR, Western blot, and ELISA. The role of chondrocyte-secreted Netrin-1 on HUVEC functions was assessed by immunological neutralization using an anti-Netrin-1 monoclonal antibody. RESULTS: As compared with medium conditioned by non-osteoarthritic chondrocytes, medium conditioned by osteoarthritic chondrocytes permitted tube formation by HUVEC. Both non-osteoarthritic and osteoarthritic chondrocytes expressed Netrin-1 at the RNA and protein levels. At the RNA level, Netrin-1 expression did not differ between non-osteoarthritic and osteoarthritic chondrocytes. At the protein level, Netrin-1 appeared as a full protein of 64 kDa in non-osteoarthritic chondrocytes and as two cleaved proteins of 55 kDa and 64 kDa in osteoarthritic chondrocytes. Immunological neutralization of endogenous Netrin-1 reduced the pro-angiogenic and pro-inflammatory transcriptional profile of HUVEC treated with the medium conditioned by osteoarthritic chondrocytes, as well as their capacities to form tubes. CONCLUSIONS: Medium conditioned by osteoarthritic chondrocytes permits tube formation by HUVEC in vitro. This permissive effect is mediated by Netrin-1.

Time is Money! Influence on Operating Theater and Sterilization Times of Patient-specific Cutting Guides and Single-use Instrumentation for Total Knee Arthroplasty: A Full Factorial Design of 136 Patients.

Background: Patient-specific cutting guides (PSGs) and single-use disposable instrumentation (SUI) have emerged as potential beneficial innovations for total knee arthroplasty. The aim of this study was to evaluate the impact of PSG and SUI for total knee arthroplasty on operating room (OR) and sterilization times. Methods: A monocentric, prospective, interventional, full factorial design study, including 136 patients, compared patient-specific (PSG, n = 68) to conventional cutting guides (n = 68) and SUI (n = 68) to conventional instrumentation (CVI, n = 68). In the OR, we recorded the number of instrument trays, operating time, and room occupancy time. In the central sterile services department, the total sterilization duration was assessed. The primary outcome was operating time and sterilization duration. Secondary outcomes were difference in the number of trays, Oxford Knee Score, and postoperative mechanical axis. Results: The median operating time was 80 minutes (Q1-Q3: 73-90) and was significantly increased for SUI compared to that for CVI (+5 minutes, P = .0072). The median sterilization duration was 1261 minutes (Q1-Q3: 934-1603). It was significantly in favor of SUI (936 minutes) over CVI (1565 minutes) (+629 minutes, P < .0001). The total number of instrument trays was 404 for 136 patients: 252 for CVI and 152 for SUI (P < .0001) and 189 for PSG and 215 for conventional cutting guides (P = .0006). There was no significant difference in OKS (P = .86) nor in the postoperative alignment which was between 177° and 183° (75% patients, P = .24). Conclusions: SUI lowers the number of instrument trays and sterilization duration. PSG is not associated with significant OR or sterilization time reduction. The use of SUI could reduce the risk of noncompliance of instrument trays.

Does delayed weight bearing in the surgical management of fractures of the upper end of the femur in the elderly lead to more complications? A prospective study.

INTRODUCTION: Fractures of the upper end of the femur (FUEF) lead to increased mortality and dependence in the elderly. However, mechanical complications after surgery persist in up to 20% of cases, which may justify a delayed resumption of full weight bearing to protect the osteosynthesis during consolidation. HYPOTHESIS: Our hypothesis was that the late resumption of weight bearing in an elderly population after a FUEF would be limited by a higher frequency of medical complications. METHODS: This was a prospective monocentric study including patients aged 80 or over with an isolated FUEF requiring osteosynthesis. The operator decided on the discharge. The primary endpoint was to show a difference in a medical complication score created for this study (APRETAR), between a group with, and a group without, weight bearing delayed by 45 days. RESULTS: Between 2016 and 2019, 254 patients (88±5.6 years, 77.6% women) were included, and of these, 70 (27.6%) had delayed weight bearing. The mean APRETAR at 45 days was greater in the delayed weight bearing group (5.9±8.6 vs. 5.7±11.0; p<0.001). One-year mortality was 12.6% (32 patients), with no difference between the two groups (p=0.51). The level of dependence was significant (IADL at 2.2±1.7), with some comorbidities (Charlson at 2.9±2.2 and CIRS-G at 6.5±4.3) and all comparable across the two groups but with low cognitive levels, especially in the group with delayed weight bearing (MMSE 15.9±10.7 vs. 21±6.9; p<0.001). CONCLUSION: This prospective study shows that delaying weight bearing in the elderly population, even for mechanical problems with FUEF, statistically increases medical complications but in a clinically acceptable manner. LEVEL OF EVIDENCE: II, Prospective cohort study.

Mid and long-term overall survival after carcinologic resections of thyroid cancer bone metastases.

Background: Bone metastases in thyroid cancer impair the patient's quality of life and prognosis. Interestingly, wide margins resection as the surgical treatment of bone metastases might improve the overall survival (OS). Nonetheless, data are lacking regarding the potential benefits of this strategy. Methods: In order to assess the OS of patients with thyroid cancer after a bone metastases carcinologic resection, a retrospective multicentric study was performed, evaluating the 1, 5, 10 and 15 years-OS along with the potential prognosis associated factors. Results: 40 patients have been included in this multicentric study, with a mean follow-up after surgery of 46.6 ± 58 months. We observed 25 (62.5%) unimestastatic patients and 15 multimetastatic patients (37.5%). The median overall survival after resection was 48 ± 57.3 months. OS at 1, 5, 10, and 15 years was respectively 76.2%, 63.6%, 63.6%, and 31.8%. Survival for patients with a single bone metastasis at 15 year was 82.3%, compared with 0.0% (Log Rank, p = 0.022) for multi-metastatic bone patients. Conclusions: This study advocates for an increased long term 10-year OS in patients with thyroid cancer, after resection of a single bone metastasis, suggesting the benefits of this strategy in this population.

Proximal femur versus acetabular extra-articular resection of the hip joint for primary malignant bone tumors: a retrospective comparative review of 33 cases.

INTRODUCTION: Extra-articular resection (EAR) of the hip joint is prone to significant complications and morbidity. Thus, this study evaluates the cumulative incidences and main reasons of reoperation following EAR of primary malignant bone tumors (PMBT) of the hip to determine whether the outcomes are different between EAR of the pelvis and that of the proximal femur. PATIENTS AND METHODS: Thirty-three patients presented with a PMBT of the proximal femur or pelvis were included in this study. Among all PMBTs, 58% originated from the pelvis and 42% were from the proximal femur. Twenty patients had chondrosarcomas (61%), 10 had osteosarcomas (30%), and 3 had sarcomas of another histological subtype (9%). RESULTS: The mean follow-up was of 76 months (range: 24-220 months). The cumulative probabilities of revision for any reason were 52% (95% confidence interval [CI] 30-70%) 5 years after surgery. The 5-year cumulative probabilities of revision were 13% (95% CI 4-27%), 24% (95% CI 10-42%), and 34% (95% CI 14-56%) for mechanical, infectious, and tumoral reasons, respectively. The 5-year cumulative probabilities of revision for any reason were 78% (95% CI 37-94%) and 14% (95% CI 2-38%) for the pelvis and proximal femur, respectively (p = 0.004). Posterior column preservation was significantly associated with more mechanical complications even after adjusting for the resection site (p = 0.043). CONCLUSION: Half of patients undergoing EAR of the hip joint for PMBT of the proximal femur or acetabulum will require another operation. EAR of the pelvis is associated with significantly worse outcome than EAR of the proximal femur.

Clinical results after surgical resection of benign solitary schwannomas: A review of 150 cases.

INTRODUCTION: Peripheral nerve schwannomas are the most common nerve tumors. While they are efficiently treated with surgery, the risk of neurological complications, especially sensory deficits, remains debated. HYPOTHESIS: We postulate that rates of post-operative sensory deficits in peripheral schwannoma surgery are low and are not increased in schwannomas of the hand, in which preservation of discriminative tact is of prime functional importance. MATERIALS AND METHODS: A retrospective multicenter study was carried out on 150 patients with an isolated peripheral schwannoma operated between 2002 and 2018, including 11 patients with schwannomas of the hand. All cases were reviewed preoperatively and postoperatively with a detailed exam of the neurological status. RESULTS: Most schwannomas were located in the lower limbs (58%). The two main affected trunks were the posterior tibial nerve in the lower limb and the median nerve in the upper limb. The average preoperative tumor volume measured on MRI was 2.93 cm3 [0.11 cm3-25 cm3]. The most common preoperative symptoms were paresthesia (77.1%) and pseudo-Tinel sign (55.7%). Less frequently, pain (50.3%) and hypoesthesia (18.1%) were observed. On the other hand, preoperative neurological motor manifestations remained exceptional (3.3%). The rates of new post-operative motor deficits, paresthesias, and sensory deficits were 4.6%, 10.9% and 8% respectively and were not increased in schwannomas of the collateral nerves of the hand. CONCLUSION: Surgical resection is a safe procedure for peripheral nerve schwannoma treatment with satisfying functional results and an acceptable risk of nerve injury, especially for sensory function. LEVEL OF PROOF: D; Multicenter retrospective study.

Effect of Prehabilitation Before Total Knee Replacement for Knee Osteoarthritis on Functional Outcomes: A Randomized Clinical Trial.

Importance: Multidisciplinary prehabilitation before total knee replacement (TKR) for osteoarthritis may improve outcomes in the postoperative period. Objective: To compare multidisciplinary prehabilitation with usual care before TKR for osteoarthritis in terms of functional independence and activity limitations after surgery. Design, Setting, and Participants: This prospective, open-label randomized clinical trial recruited participants 50 to 85 years of age with knee osteoarthritis according to the American College of Rheumatology criteria for whom a TKR was scheduled at 3 French tertiary care centers. Recruitment started on October 4, 2012, with follow-up completed on November 29, 2017. Statistical analyses were conducted from March 29, 2018, to March 6, 2019. Interventions: Four supervised sessions of multidisciplinary rehabilitation and education (2 sessions per week, at least 2 months before TKR, delivered to groups of 4-6 participants at each investigating center; session duration was 90 minutes and included 30 minutes of education followed by 60 minutes of exercise therapy) or usual care (information booklet and standard advice by the orthopedic surgeon) before TKR. Main Outcomes and Measures: The short-term primary end point was the proportion of participants achieving functional independence a mean (SD) of 4 (1) days after surgery defined as level 3 on the 4 functional tests. The midterm primary end point was activity limitations within 6 months after TKR assessed by the area under the receiver operating characteristic curve of the self-administered Western Ontario Questionnaire and McMaster Universities Osteoarthritis Index function subscale. Results: A total of 262 patients (mean [SD] age, 68.6 [8.0] years; 178 women [68%]) were randomized (131 to each group). A mean (SD) of 4 (1) days after surgery, 34 of 101 (34%) in the experimental group vs 26 of 95 (27%) in the control group achieved functional independence (risk ratio, 1.4; 97.5% CI, 0.9-2.1; P = .15). At 6 months, the mean (SD) area under the curve for the Western Ontario Questionnaire and McMaster Universities Osteoarthritis Index function subscale was 38.1 (16.5) mm2 in the experimental group vs 40.6 (17.8) mm2 in the control group (absolute difference, -2.8 mm2; 97.5% CI, -7.8 to 2.3; P = .31 after multiple imputation). No differences were found in secondary outcomes. Conclusions and Relevance: This randomized clinical trial found no evidence that multidisciplinary prehabilitation before TKR for osteoarthritis improves short-term functional independence or reduces midterm activity limitations after surgery. Trial registration: ClinicalTrials.gov Identifier: NCT01671917.

Management of sarcoma recurrence after megaprosthesis of the knee.

BACKGROUND: The management of local sarcoma recurrence about the knee (at the distal femur or proximal tibia) is challenging. The objective of this study was to describe the locations of local sarcoma recurrences about knee megaprostheses, the treatments used for each type of recurrence, and the outcomes according to the treatment used. HYPOTHESIS: The strategy for treating a local sarcoma recurrence about the knee must be based on the topography of tumour involvement. MATERIALS AND METHODS: We included 13 patients who had local sarcoma recurrence about a knee megaprosthesis and were followed up for at least 2 years. The diagnosis was osteosarcoma in 10 patients and chondrosarcoma in 3 patients. The distal femur was involved in 11 patients and the proximal tibia in 2 patients. We classified the patients into two groups based on whether the tumour involved important structures or was at a distance within the soft tissues. RESULTS: The recurrence was a nodule at a distance of important structures in 8 (57%) patients, in whom the mean time to recurrence was 15 months (range, 2-34 months). The remaining 5 (38.5%) patients had involvement of important structures in the popliteal fossa and a mean time to recurrence of 42 months (range, 16-80 months). Surgery was performed in 10 patients; the other 3 patients received palliative care due to rapid metastatic dissemination. Of the 6 patients who had surgery for a recurrence at a distance from important structures, 5 (83.3%) underwent isolated tumour resection with the goal of salvaging the limb and 1 (16.7%) underwent transfemoral amputation. Transfemoral amputation was performed in all 3 patients who had surgery for popliteal recurrences. Lung metastases were detected in 10 (77%) patients, 2 at the time of initial sarcoma diagnosis and 8 at the time of the local recurrence. At last follow-up, 5 patients were alive, including 2 (33.3%) of the 6 patients with recurrences at a distance from important structures and all 3 patients with popliteal recurrences. Of the 5 survivors at last follow-up, 2 had metastases. CONCLUSION: In patients with local recurrence of knee sarcoma, three presentations can be distinguished. When the local recurrence coincides with distant recurrence, failure to control the disease is likely and the local treatment should be designed as a component of palliative care. When no metastases are detected but the local recurrence is in contact with important structures, amputation is advisable at present given the complexity of limb-salvage surgery and high risk of further local recurrence. Finally, when no metastases are detected and the local recurrence is at a distance from important structures, limb-salvage surgery deserves consideration. LEVEL OF EVIDENCE: IV, retrospective observational study.