Gait Analysis and Functional Knee Scores in Primary Knee Osteoarthritis and Their Correlation with Progression of the Disease in the Indian Population.

Introduction: Osteoarthritis of the knee is a leading cause of disability and is a multi-factorial disease. Moreover, it is partly considered a mechanically driven disease in which higher abnormally disbursed forces play a prime role. With the progression of the disease, the gait function declines, so a comprehensive and objective evaluation of gait function would help in prognostic evaluation and management. Materials and Methods: This study included two groups: patients with primary knee osteoarthritis and a control group of healthy volunteers. Gait analysis and functional knee scores were evaluated for all the subjects. The KOOS score, temporal parameters excluding the step length, and spatial parameters excluding the stance phase percentage were evaluated for an individual as a whole. The KSS score, kinetic parameters, kinematic parameters, step length, and stance phase percentage were calculated for each knee separately. Each knee of the patient and controls was taken as 1 sample and categorized as per Kellgren-Lawrence score. An asymptomatic control group of subjects were included in group A. Symptomatic patients with KL grades 1, 2 were included in group M, and those with KL grades 3, 4 were included in group S. The kinetic and kinematic parameters and KSS score were compared among the three groups. Results: A total of 60 subjects were included of which 40 were patients and 20 were controls. In the control group, the age ranged from 22 to 48 years with a mean age of 28.6 years. In the patient group, the mean age was 60.3 years. Patients with knee osteoarthritis were significantly obese with slower walking speed, short stride length, longer stride time, and decreased cadence compared to the asymptomatic group. There was a significant difference in spatiotemporal parameters, functional scores, and kinetic and kinematic parameters among the groups. Conclusion: Various spatiotemporal, kinetic, and kinematic parameters like peak knee flexion angle, abduction/adduction angle, peak knee adduction moment, range of knee flexion, peak knee flexion, and gait deviation index along with functional scores varied significantly with the progression of the disease. Supplementary Information: The online version contains supplementary material available at 10.1007/s43465-024-01103-9.

Treatment outcomes in patients with Ewing sarcoma of the spine in a resource-challenged setting: 17-year experience from a single center in India.

Ewing sarcoma (ES) of the spine is a rare childhood cancer with sparse literature on treatment outcomes. We aimed to describe survival outcomes and prognostic factors in patients with spinal ES treated at a single institute in a resource-challenged setting. We conducted a retrospective analysis of patients with spinal ES registered at a tertiary care oncology center between 2003-2019. Clinical patient data was retrieved from hospital records. Cox regression analysis was used to identify the association of baseline clinical parameters with event free survival (EFS) and overall survival (OS). A cohort of 85 patients was analyzed including 38 (45%) patients with metastatic disease. The median age was 15 years with 73% being male. Local therapy was administered in 62 (72.9%) patients with surgery alone in 8 (9.4%), radiotherapy alone in 36 (42.4%) and both in 18 (21.2%) patients. A higher proportion of males received local therapy than females (80.3% versus 59.1%; p = 0.049). The median EFS and OS were 20.1 and 28.6 months, respectively. On univariable analysis, age ≤ 15 years, female sex, serum albumin ≤3.5 g/dL and hemoglobin ≤11 g/dL were associated with inferior EFS while younger age, female sex, hypoalbuminemia and metastatic disease were associated with inferior OS. On multivariable analysis, only hypoalbuminemia was predictive for inferior EFS (HR:2.41; p = 0.005) while hypoalbuminemia (HR:2.06;p = 0.033) and female sex (HR:1.83; p = 0.046) were associated with inferior OS. We concluded that hypoalbuminemia confers poor prognosis in ES spine. Survival outcomes are poorer in females treated in our setting, possibly due to prevailing sex-based biases.

Formulation and validation of a baseline prognostic score for osteosarcoma treated uniformly with a non-high dose methotrexate-based protocol from a low middle income healthcare setting: a single centre analysis of 594 patients.

Introduction: The outcomes of osteosarcoma in low middle income countries (LMICs) are different due to patients presenting in advanced stages, resource constraints and the use of non-high-dose-methotrexate (HDMTX)-based regimens. This study derived and validated a prognostic score for osteosarcoma that integrates biologic and social factors and is tailored for patients from an LMIC setting using a non-HDMTX-based protocol. Materials and methods: A retrospective study including osteosarcoma patients enrolled for treatment at a single tertiary care centre in India between 2003-19 was conducted. Baseline biologic and social characteristics were extracted from medical records and survival outcomes were noted. The cohort was randomised into a derivation and validation cohort. Multivariable Cox regression was used to identify baseline characteristics that were independently prognostic for survival outcomes in the derivation cohort. A score was derived from the prognostic factors identified in the derivation cohort and further validated in the validation cohort with estimation of its predictive ability. Results: 594 patients with osteosarcoma were eligible for inclusion in the study. Around one-third of the cohort had metastatic disease with 59% of the patients residing in rural areas. The presence of metastases at baseline (HR 3.39; p<0.001; score=3), elevated serum alkaline phosphatase (SAP) >450 IU/L (HR 1.57; p=0.001; score=1) and baseline tumour size > 10 cm (HR 1.68; p<0.001; score=1) were identified to be independent factors predicting inferior event free survival (EFS) and were included in development of the prognostic score. Patients were categorized as low risk (score 0), intermediate risk (score 1-3) and high risk (4-5). Harrell's c-indices for the score were 0.682, 0.608 and 0.657 respectively for EFS in the derivation, validation and whole cohort respectively. The timed AUC of ROC was 0.67 for predicting 18-month EFS in the derivation, validation and whole cohorts while that for 36-month EFS were 0.68, 0.66 and 0.68 respectively. Conclusions: The study describes the outcomes among osteosarcoma patients from an LMIC treated uniformly with a non-HDMTX-based protocol. Tumor size, baseline metastases and SAP were prognostic factors used to derive a score with good predictive value for survival outcomes. Social factors did not emerge as determinants of survival.

Factors affecting the incorporation of extracorporeally irradiated autograft for the treatment of bone tumours-a retrospective analysis from a tertiary referral centre.

PURPOSE: Re-implantation of the tumor bearing autograft following extracorporeal radiation therapy (ECRT) has been established as an oncologically safe biological reconstruction technique following resection of bone sarcomas. However, factors affecting the ECRT graft-host bone incorporation have not been fully investigated. An insight into the factors that influence graft incorporation can circumvent the complications and increase graft survival. METHODS: A total of 96 osteotomies in 48 patients with intercalary resections of primary extremity bone sarcomas (mean age 15.8 years, mean follow-up 42.1 months) were analyzed retrospectively for factors ECRT autograft-host bone union. RESULTS: On univariate analysis, age < 20 years, metaphyseal osteotomy site, V-shaped diaphyseal osteotomy, and use of additional plate at diaphyseal osteotomy had a significantly faster time to union, while gender, tumour type, bone involved, resection length, chemotherapy, type of fixation, and use of intra-medullary fibula did not influence union time. In multivariate analysis, V-shaped diaphyseal osteotomy and use of additional plate at diaphyseal ostetomy were the independent factors with favourable time to union. None of the analyzed factors was found to have a significant effect on the union rate. The major complications were non-union in 11.4% patients, graft failure in 2.1%, infection in 12.5%, and soft tissue local recurrences in 14.5% patients. CONCLUSION: Modified diaphyseal osteotomy and augmentation of the stability of the reconstruction using additional small plates enhance the incorporation of ECRT autograft.

Prepubic inflammatory liposarcoma presenting as urosepsis.

Inflammatory well-differentiated liposarcoma is a rare soft-tissue tumor which is predominantly retroperitoneal in origin. We report a 72-year-old male without co-morbidities with suspected urosepsis and an obstructing ureteric calculus. Despite adequate diversion and broad-spectrum antimicrobials, the leukocytosis persisted. Further imaging revealed a locally infiltrating prepubic mass which was suspicious of a lymphoid malignancy and was found to be a high-grade liposarcoma on biopsy. He underwent open wide local resection of the tumor and the histopathology revealed an inflammatory well-differentiated liposarcoma with areas of neutrophilic abscess and necrosis. A dramatic response to the surgical resection was seen and the leukocytosis resolved within a few days.

Determinants and impact of diagnostic interval in bone sarcomas: A retrospective cohort study.

BACKGROUND: Diagnostic delays in cancers are frequent in developing countries due to poor health infrastructure. Existing literature from developed countries suggests that diagnostic interval in bone sarcomas is primarily dictated by tumour biology with no impact on survival. This study evaluates the social and biological determinants of the diagnostic interval in bone sarcomas in a resource-challenged setting and assesses its impact on treatment outcomes. METHODS: A retrospective single-institutional study was conducted on patients with high-grade bone sarcomas recorded in the sarcoma clinic database between 2003 and 2018. Baseline clinical characteristics and treatment outcomes were recorded. Logistic regression was performed to assess the impact of baseline clinical and social characteristics (distance from treating centre and rural vs. urban residence) on the diagnostic interval. Further, the impact of diagnostic interval on histologic response to neoadjuvant chemotherapy, amputation requirement in extremity sarcomas and survival was evaluated. RESULTS: A total of 1227 patients were included for analysis. The median diagnostic interval was 4 months (3-7 months). Age above 18 years, Ewing sarcoma (ES) diagnosis, absence of fever at presentation and tumour size above 7.5 cm were predictors of a longer diagnostic interval (>4 months). The length of the diagnostic interval did not impact amputation requirement or survival outcomes. However, the proportion of patients with good necrosis post-neoadjuvant chemotherapy was lower among patients with longer diagnostic intervals (25% vs. 34·16%; p-value = .04). CONCLUSION: Tumour characteristics rather than social factors determined the diagnostic interval. Diagnostic interval did not impact survival outcomes even in a resource-constrained setting.

Serendipitous Diagnosis of Tertiary Hyperparathyroidism in a Case Purportedly thought to have Skeletal Metastases.

Tertiary hyperparathyroidism (THPT) is characterized by over secretion of parathyroid hormone caused by long-standing secondary hyperparathyroidism. THPT can affect the bones as well as cause extraskeletal calcifications. The bony lesions often mimic multiple skeletal metastases or multiple myeloma. We report a case of a 48-year-old man with chronic kidney disease on dialysis, who presented with chief complaints of low back ache and swelling over the left clavicle. In view of clinical suspicion of malignancy with bony metastases, he underwent 18F-fluorodeoxyglucose positron emission tomography/computed tomography and was subsequently found to have parathyroid adenomas, which were confirmed on 99mTc-methoxy-isobutyl-isonitrile scintigraphy.

Non-invasive intravoxel incoherent motion MRI in prediction of histopathological response to neoadjuvant chemotherapy and survival outcome in osteosarcoma at the time of diagnosis.

BACKGROUND: Early prediction of response to neoadjuvant chemotherapy (NACT) is important to aid personalized treatment in osteosarcoma. Diffusion-weighted Intravoxel Incoherent Motion (IVIM) MRI was used to evaluate the predictive value for response to NACT and survival outcome in osteosarcoma. METHODS: Total fifty-five patients with biopsy-proven osteosarcoma were recruited prospectively, among them 35 patients were further analysed. Patients underwent 3 cycles of NACT (Cisplatin + Doxorubicin) followed by surgery and response adapted adjuvant chemotherapy. Treatment outcomes were histopathological response to NACT (good-response ≥ 50% necrosis and poor-response < 50% necrosis) and survival outcome (event-free survival (EFS) and overall survival (OS)). IVIM MRI was acquired at 1.5T at baseline (t0), after 1-cycle (t1) and after 3-cycles (t2) of NACT. Quantitative IVIM parameters (D, D*, f & D*.f) were estimated using advanced state-of-the-art spatial penalty based IVIM analysis method bi-exponential model with total-variation penalty function (BETV) at 3 time-points and histogram analysis was performed. RESULTS: Good-responders: Poor-responders ratio was 13 (37%):22 (63%). EFS and OS were 31% and 69% with 16.27 and 25.9 months of median duration respectively. For predicting poor-response to NACT, IVIM parameters showed AUC = 0.87, Sensitivity = 86%, Specificity = 77% at t0, and AUC = 0.96, Sensitivity = 86%, Specificity = 100% at t1. Multivariate Cox regression analysis showed smaller tumour volume (HR = 1.002, p = 0.001) higher ADC-25th-percentile (HR = 0.047, p = 0.005) & D-Mean (HR = 0.1, p = 0.023) and lower D*-Mean (HR = 1.052, p = 0.039) were independent predictors of longer EFS (log-rank p-values: 0.054, 0.0034, 0.0017, 0.0019 respectively) and non-metastatic disease (HR = 4.33, p < 10-3), smaller tumour-volume (HR = 1.001, p = 0.042), lower D*-Mean (HR = 1.045, p = 0.056) and higher D*.f-skewness (HR = 0.544, p = 0.048) were independent predictors of longer OS (log-rank p-values: < 10-3, 0.07, < 10-3, 0.019 respectively). CONCLUSION: IVIM parameters obtained with a 1.5T scanner along with novel BETV method and their histogram analysis indicating tumour heterogeneity were informative in characterizing NACT response and survival outcome in osteosarcoma.

Functional Outcomes of Centralization of the Ulna as a Method of Reconstruction Following Resection of Campanacci Grade 3 Giant Cell Tumor of the Distal Radius.

PURPOSE: Wrist reconstruction after distal radial tumor resection poses a challenge to the orthopedic oncologist. We evaluated the functional outcomes of centralization of the ulna with ulnocarpal arthrodesis as a method of reconstruction following resection of distal radius tumors, using impairment measures and patient-reported outcomes. METHODS: Evaluation of functional outcome was performed using the Musculoskeletal Tumor Society 93 scoring system and Disabilities of the Arm, Shoulder, and Hand questionnaire. We also determined hand grip strength on the affected side, time to radiologic union at the ulnocarpal junction and reduction in wrist circumference. Local complications and oncologic outcomes were recorded. RESULTS: The study included 26 patients with Campanacci grade 3 giant cell tumor of the distal radius. Mean follow-up period in the study was 32.8 ± 12 months. Mean resection length was 10.3 ± 2.5 cm. Radiologic union at the ulnocarpal junction was achieved in 38.5%, 77% and 96% of the patients by 4, 5, and 6 months respectively. Mean hand grip strength was 74 ± 3.9% of the contralateral side whereas mean reduction in wrist circumference was 16.9 ± 6.4%. A good functional outcome with a mean the Musculoskeletal Tumor Society 93 score of 26 ± 1.4 and mean Disabilities of the Arm, Shoulder, and Hand score of 10.5 ± 6.3 was observed. Fracture of the ulna, hardware loosening, and reflex sympathetic dystrophy were each noted in 1 patient, with an overall complication rate of 10.7% (3/28). No patient had nonunion, infection, or local recurrence. CONCLUSIONS: This is a simple and effective modality of reconstruction after resection of distal radial tumors. It provides good functional outcome and preservation of good hand grip strength, with low complication rates. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Infected Lower Limb Megaprosthesis on 68Ga-NOTA-Ubiquicidin PET/CT Imaging.

Pain after prosthesis implant is a common clinical problem which requires distinction of septic from aseptic causes since the treatment differs. Non-invasive imaging methods play an important role in the diagnosis. Radiolabelled ubiquicidin can be used for imaging infection by binding directly to bacterial cell wall. We describe a case of a 24-year-old man with right lower limb megaprosthesis which did not show any loosening on computed tomography (CT) but was accurately diagnosed as infected prosthesis with 68Ga-NOTA-ubiquicidin(29-41) acetate scan.

Development and validation of a prognostic score at baseline diagnosis for Ewing sarcoma family of tumors: a retrospective single institution analysis of 860 patients.

INTRODUCTION: Prognostic scores in Ewing sarcoma including baseline clinical and laboratory characteristics are necessary for pre-treatment risk stratification. In this study, we formulated and validated a prognostic model for baseline risk categorization in Ewing sarcoma. MATERIALS AND METHODS: A retrospective single-institutional study was conducted on Ewing sarcoma patients treated uniformly between January 2003 and December 2018. Baseline clinical/pathological characteristics and survival outcomes were noted from medical records. The cohort was randomised into a derivation and validation cohort. A prognostic score was formulated by including independent prognostic factors from the derivation cohort by multivariable analysis. The prognostic model was validated in the validation cohort along with estimation of its predictive ability. RESULTS: A total of 860 patients were included with 40.3% having baseline metastases. Tumor diameter >5 cm (HR 2.04; P<0.001; score 2), baseline metastases (HR 2.33; P<0.001, score 2), and total leucocyte count >11000/mm3 (HR 1.44; P=0.015; score 1) were independent predictors of overall survival in derivation cohort and included for prognostic score calculation. Patients were categorized into low (score 0), intermediate (score 1-3) and high-risk (score 4-5) groups. Harrell's c-indexes of the model were 0.625, 0.622 and 0.624 in the derivation, validation and whole cohort respectively. The timed AUC of ROC of the prognostic score-group for 5-year survival was 0.72, 0.71 and 0.73 in the derivation, validation and whole cohort respectively. CONCLUSIONS: We have formulated and validated a prognostic score for Ewing sarcoma incorporating baseline clinical and laboratory parameters, with fair predictive ability for risk stratification and facilitating risk-adapted personalized therapy.

Resource-appropriate selection of osteosarcoma treatment protocols in low- and middle-income countries.

Osteosarcoma is a rare malignancy; however, it is still the most common primary bone tumor in adolescents and young adults. Chemotherapy improves survival indubitably in osteosarcoma; nevertheless, the concern is the stagnant progress since the last several decades. There are a handful of active agents and unresolved issues, especially in choosing the ideal chemotherapy regimen. The oncology community is in equipoise regarding the position of high-dose methotrexate (HDMTX), mandatory or adjunct. The choice of therapy becomes widely relevant, including in low- and middle-income countries (LMIC), where HDMTX administration brings additional complexities. Research into novel non-HDMTX-based protocols adapted to the available resources is pivotal in improving disease outcomes, especially in LMIC. The current review focuses on real-world challenges in decision-making and provides a comprehensive overview of the evolution of treatment protocols in LMIC.

Controversies and Challenges in the Management of Osteosarcoma-an Indian Perspective.

Osteosarcoma (OGS) is the most common primary bone tumor in children and adolescents which requires a multidisciplinary approach to management. Although chemotherapy and surgery can cure more than half of localized OGS cases, the unique challenges faced by resource-limited countries like India make this outcome difficult to achieve. Various questions in the management of OGS including role of high-dose methotrexate (HDMTX) in neoadjuvant setting, triplet vs doublet chemotherapy, intensification of chemotherapy based on response in setting of doublet, and indigenous prosthesis in setting of limb salvage need to be defined. Similarly, in the metastatic and recurrent setting, questions regarding intent of treatment, indications of chemotherapy, timing of surgery, and role of targeted therapies need clarification. Lack of randomized trials from India makes definite conclusions difficult, but an attempt can be made to define the best approach in the Indian scenario from available evidence. Hence, a critical review of literature from India and the West was done to define possible management approaches and highlight the lacuna for future research.

Is Pulley Reconstruction Better Than Pulley Release for De Quervain's Tenosynovitis? A Double-Blind Randomized Controlled Trial.

Purpose The aim of this study was to compare the results of surgeries of the De Quervain's disease (DQD) through a randomized control trial. Materials and Methods We treated 40 cases of De Quervain's tenosynovitis in 2 groups: 20 patients by pulley release method and another 20 patients by pulley reconstruction method. The patients were selected as per the random table number. The clinical data, numeric Visual Analogue Scale (VAS) score, Quick DASH-Disabilities of the Arm, Shoulder, and Hand-score, Mayo Wrist Score, and subluxation of the tendons in dynamic ultrasonography (USG) during wrist hyperflexion and abduction of the thumb test were noted preoperatively and 6 months after the operation. All patient charts were reviewed and data analysis was done after completion of the study. Results All patients improved after surgery. There was no difference in clinical outcome data, numeric VAS score, Quick DASH Score, and Mayo Wrist Score ( p -value > 0.05). There were four patients with tendon subluxation under USG in pulley release group, out of which only one patient was clinically symptomatic. There was no tendon subluxation in pulley reconstruction group. The tendon subluxation between the two groups was not found to be statistically significant ( p -value: 0.661). Conclusion Although, higher numbers of subluxation were found in release group, there was no statistically significant difference in the outcome of the two surgical procedures for DQD. This study is a pilot study, and it may act as the groundwork over which further studies may be performed. Level of Evidence This is a Level I study.

Comparison of Denosumab and Zoledronic acid as neoadjuvant therapy in patients with giant cell tumor of bone.

OBJECTIVES: Both Zoledronic acid and denosumab have been utilized in neo-adjuvant setting for facilitating surgery and downsizing the lesion in Giant cell tumor (GCT). This study is aimed at comparing Zoledronic acid and Denosumab, when used in neo-adjuvant setting, in terms of radiological and clinical outcomes in GCT undergoing surgical intervention. PATIENTS AND METHODS: Patients undergoing surgical intervention for GCT who received either denosumab or Zoledronic acid as neoadjuvant agents were retrospectively analyzed for reduction in tumor load radiologically, change in surgical plan after therapy, facilitation of surgery, therapy related complications, cost of treatment, rate of local recurrence and clinical outcomes. RESULTS: Twenty patients received denosumab and 19 patients received Zoledronic acid as neoadjuvant agent. There was no significant difference in radiological outcomes, facilitation of surgery and clinical outcomes at end of follow-up. Zoledronic acid group had lower number of recurrences, however, not statistically significant. Therapy with Zoledronic acid was significantly cheaper (p = 0.001). CONCLUSION: Zoledronic acid is a cheaper alternative to denosumab in terms of solidification of lesion, reducing recurrence rates and improving clinical outcomes. Larger prospective studies required to further delineate this outcome with Zoledronic acid.

Limb Salvage Surgery in Fungating Giant Cell Tumors: A Report of Three Cases.

INTRODUCTION: The WHO defines giant cell tumor as a benign locally aggressive neoplasm with metastasizing capacity and aggressive behavior. Very rarely, these tumors are seen fungating, mostly when neglected. But when they do, the treatment option commonly conferred is amputation of the limb which is disabling and traumatizing. CASE REPORT: We report three cases of fungating limb masses (proximal tibia, distal fibula, and distal radius) diagnosed with giant cell tumor histologically, undergoing limb saving surgeries with various reconstruction techniques to endorse a good quality of life and functioning limb. CONCLUSION: Our study is one of the earliest to report medium-term follow-up after such limb salvage procedure. We recommend that salvage procedures should be considered in giant cell tumors even in the presence of fungation if there is no neurovascular encasement.

Relationship between height and osteosarcoma at the time of diagnosis in the Indian population: A retrospective study.

BACKGROUND: It has been indicated in several instances that tall stature is also an important risk factor in the development of osteosarcoma. This relationship between height and osteosarcoma is substantiated even more by the increasing evidences being put forth in the recent literature on dependence of certain tumors on the growth factors and their receptors, acting through autocrine or paracrine mechanisms. There has been no study on the Indian population that attempts to define such a relationship. PURPOSE: The primary objective of this study was to define relationship between height of patients and osteosarcoma at the time of diagnosis in the Indian population. MATERIALS/METHODS: Retrospective data was collected from the old hospital records. Height of patients at the time of diagnosis was compared with expected height of patients of the same age with reference to the standardized growth charts provided by the Indian Academy of Paediatrics. RESULTS: Out of 98 patients, there were 65 male and 33 female patients with M: F ratio being 1.97:1. The mean age at diagnosis was 17 (SD = 8) years with range of 5-55 years (median = 17 years). Height of the patients at the time of diagnosis was 155.18 (SD = 15.47) cm with range of 115 cm-184 cm (median = 159 cm). Overall, patients with Osteosarcoma were found to be shorter than the expected height deduced from the national growth charts. When patients were divided into two groups of those who were of growing age and those who had completed growth, results were similar. CONCLUSION: The observation that majority of patients with osteosarcoma in our study were stunted, is an important finding. It could be deduced from this observation that these patients are unable to mount the usual biological response to the overstimulated growth as part of tumorigenesis in osteosarcoma. This could point to a different scenario in the Indian population and more studies need to be carried out with larger number of patients to further elaborate on this observation.

Outcomes of major musculoskeletal oncological reconstructions using prolene mesh-a retrospective analysis from a tertiary referral centre.

BACKGROUND: Adequate reconstruction of the soft tissue defect following resection of bone tumors is challenging. Prolene mesh, despite being a useful tool, is not widely used due to the fear of deep infection. The aim of this study was to evaluate the functional outcome and complications of using a Prolene mesh in oncological reconstructions. METHODS: A retrospective study was conducted in bone tumor patients with soft tissue reconstruction using Prolene mesh between January 2017 and June 2019. Functional evaluation was done using MSTS 93 score. Complications were recorded and were classified as mechanical (dislocation and extension lag) or biological failure (wound problems and deep infection). Comparison was performed between groups with and without biological failure to identify predictive variables. RESULTS: Of 116 patients, 68 were males and 48 were females, with median age of 22.5 years. Thirty nine patients had tumors of proximal tibia, 23 of proximal femur, 25 of proximal humerus, 24 of pelvis, and five tumors at other sites. Approximately two-thirds (62.9%) of our patients underwent endoprosthetic reconstruction while the rest underwent either biological or cement spacer reconstructions. Excellent or good functional outcomes were reported in 98.3% patients as per MSTS 93 scoring. Complications were noted in 22 patients (18.9%), of which 16 had biological failure, with four patients requiring debridement and mesh removal. Dislocation of prosthesis occurred in 2 patients of proximal femur replacement. Overall re-surgery rate was 5.1% (6 patients). There was no statistically significant difference between the groups with or without biological failure with respect to demographics, site of tumor, type of procedure, blood loss, duration of surgery and history of chemotherapy. CONCLUSION: Prolene mesh is a useful tool to reconstruct the soft tissue defects following bone tumor resections. It is readily available, reliable and provides reproducible results, with no added risk of wound complications.

What Is the Comparative Ability of 18F-FDG PET/CT, 99mTc-MDP Skeletal Scintigraphy, and Whole-body MRI as a Staging Investigation to Detect Skeletal Metastases in Patients with Osteosarcoma and Ewing Sarcoma?

BACKGROUND: Skeletal metastases of bone sarcomas are indicators of poor prognosis. Various imaging modalities are available for their identification, which include bone scan, positron emission tomography/CT scan, MRI, and bone marrow aspiration/biopsy. However, there is considerable ambiguity regarding the best imaging modality to detect skeletal metastases. To date, we are not sure which of these investigations is best for screening of skeletal metastasis. QUESTION/PURPOSE: Which staging investigation-18F-fluorodeoxyglucose positron emission tomography/CT (18F-FDG PET/CT), whole-body MRI, or 99mTc-MDP skeletal scintigraphy-is best in terms of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) in detecting skeletal metastases in patients with osteosarcoma and those with Ewing sarcoma? METHODS: A prospective diagnostic study was performed among 54 of a total 66 consecutive osteosarcoma and Ewing sarcoma patients who presented between March 2018 and June 2019. The institutional review board approved the use of all three imaging modalities on each patient recruited for the study. Informed consent was obtained after thoroughly explaining the study to the patient or the patient's parent/guardian. The patients were aged between 4 and 37 years, and their diagnoses were proven by histopathology. All patients underwent 99mTc-MDP skeletal scintigraphy, 18F-FDG PET/CT, and whole-body MRI for the initial staging of skeletal metastases. The number and location of bone and bone marrow lesions diagnosed with each imaging modality were determined and compared with each other. Multidisciplinary team meetings were held to reach a consensus about the total number of metastases present in each patient, and this was considered the gold standard. The sensitivity, specificity, PPV, and NPV of each imaging modality, along with their 95% confidence intervals, were generated by the software Stata SE v 15.1. Six of 24 patients in the osteosarcoma group had skeletal metastases, as did 8 of 30 patients in the Ewing sarcoma group. The median (range) follow-up for the study was 17 months (12 to 27 months). Although seven patients died before completing the minimum follow-up, no patients who survived were lost to follow-up. RESULTS: With the number of patients available, we found no differences in terms of sensitivity, specificity, PPV, and NPV among the three staging investigations in patients with osteosarcoma and in patients with Ewing sarcoma. Sensitivities to detect bone metastases for 18F-FDG PET/CT, whole-body MRI, and 99mTc-MDP skeletal scintigraphy were 100% (6 of 6 [95% CI 54% to 100%]), 83% (5 of 6 [95% CI 36% to 100%]), and 67% (4 of 6 [95% CI 22% to 96%]) and specificities were 100% (18 of 18 [95% CI 82% to 100%]), 94% (17 of 18 [95% CI 73% to 100%]), and 78% (14 of 18 [95% CI 52% to 94%]), respectively, in patients with osteosarcoma. In patients with Ewing sarcoma, sensitivities to detect bone metastases for 18F-FDG PET/CT, whole-body MRI, and 99mTc-MDP skeletal scintigraphy were 88% (7 of 8 [95% CI 47% to 100%]), 88% (7 of 8 [95% CI 47% to 100%]), and 50% (4 of 8 [95% CI 16% to 84%]) and specificities were 100% (22 of 22 [95% CI 85% to 100%]), 95% (21 of 22 [95% CI 77% to 100%]), and 95% (21 of 22 [95% CI 77% to 100%]), respectively. Further, the PPVs for detecting bone metastases for 18F-FDG PET/CT, whole-body MRI, and 99mTc-MDP skeletal scintigraphy were 100% (6 of 6 [95% CI 54% to 100%]), 83% (5 of 6 [95% CI 36% to 100%]), and 50% (4 of 8 [95% CI 16% to 84%]) and the NPVs were 100% (18 of 18 [95% CI 82% to 100%]), 94% (17 of 18 [95% CI 73% to 100%]), and 88% (14 of 16 [95% CI 62% to 98%]), respectively, in patients with osteosarcoma. Similarly, the PPVs for detecting bone metastases for 18F-FDG PET/CT, whole-body MRI, and 99mTc-MDP skeletal scintigraphy were 100% (7 of 7 [95% CI 59% to 100%]), 88% (7 of 8 [95% CI 50% to 98%]), and 80% (4 of 5 [95% CI 28% to 100%]), and the NPVs were 96% (22 of 23 [95% CI 78% to 100%]), 95% (21 of 22 [95% CI 77% to 99%]), and 84% (21 of 25 [95% CI 64% to 96%]), respectively, in patients with Ewing sarcoma. The confidence intervals around these values overlapped with each other, thus indicating no difference between them. CONCLUSION: Based on these results, we could not demonstrate a difference in the sensitivity, specificity, PPV, and NPV between 18F-FDG PET/CT, whole-body MRI, and 99mTc-MDP skeletal scintigraphy for detecting skeletal metastases in patients with osteosarcoma and Ewing sarcoma. For proper prognostication, a thorough metastatic workup is essential, which should include a highly sensitive investigation tool to detect skeletal metastases. However, our study findings suggest that there is no difference between these three imaging tools. Since this is a small group of patients in whom it is difficult to make broad recommendations, these findings may be confirmed by larger studies in the future. LEVEL OF EVIDENCE: Level II, diagnostic study.