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

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

GRADE-ADOLOPMENT of clinical practice guideline for postmenopausal osteoporosis management-a Pakistani context.

Due to its high prevalence, we aimed to create postmenopausal osteoporosis clinical practice guideline via GRADE-ADOLOPMENT for Pakistan. We recommend a higher dose (2000-4000 IU) of vitamin D for osteoporotic patients who are old, have malabsorption, or are obese. The guideline will help standardize care provision and improve health care outcomes for osteoporosis. PURPOSE: Postmenopausal osteoporosis affects one in every five postmenopausal women in Pakistan. An evidence-based clinical practice guideline (CPG) is needed to standardize care provision to optimize health outcomes. Hence, we aimed to develop CPG for the management of postmenopausal osteoporosis in Pakistan. METHODS: The GRADE-ADOLOPMENT process was used to adopt (as is or with minor changes), exclude (omit), or adapt (modify based on local context) recommendations to the source guideline (SG)-clinical practice guidelines for the diagnosis and treatment of postmenopausal osteoporosis-2020 update from American Association of Clinical Endocrinology (AACE). RESULTS: The SG was "adoloped" to cater to the local context. The SG consisted of 51 recommendations. Forty-five recommendations were adopted as is. Due to unavailability of drugs, 4 recommendations were adopted with minor changes, and one was excluded, while one recommendation was adopted with the inclusion of use of a surrogate FRAX tool specific for Pakistan. One recommendation regarding vitamin D dosage was adapted to recommend a dose of 2000-4000 IU of vitamin D in patients with obesity, malabsorption, and old age. CONCLUSION: The developed Pakistani postmenopausal osteoporosis guideline consists of 50 recommendations. The guideline created recommends a higher dose (2000-4000 IU) of vitamin D for patients who are old, have malabsorption, or are obese, which is an adaptation from the SG by the AACE. This higher dose is justified as lower doses prove to be suboptimal in these groups and should be complemented with baseline vitamin D and calcium levels.

GRADE-ADOLOPMENT of clinical practice guideline for postmenopausal osteoporosis management-a Pakistani context

Due to its high prevalence, we aimed to create postmenopausal osteoporosis clinical practice guideline via GRADE-ADOLOPMENT for Pakistan. We recommend a higher dose (2000-4000 IU) of vitamin D for osteoporotic patients who are old, have malabsorption, or are obese. The guideline will help standardize care provision and improve health care outcomes for osteoporosis.Postmenopausal osteoporosis affects one in every five postmenopausal women in Pakistan. An evidence-based clinical practice guideline (CPG) is needed to standardize care provision to optimize health outcomes. Hence, we aimed to develop CPG for the management of postmenopausal osteoporosis in Pakistan.The GRADE-ADOLOPMENT process was used to adopt (as is or with minor changes), exclude (omit), or adapt (modify based on local context) recommendations to the source guideline (SG)-clinical practice guidelines for the diagnosis and treatment of postmenopausal osteoporosis-2020 update from American Association of Clinical Endocrinology (AACE). The SG was "adoloped" to cater to the local context. The SG consisted of 51 recommendations. Forty-five recommendations were adopted as is. Due to unavailability of drugs, 4 recommendations were adopted with minor changes, and one was excluded, while one recommendation was adopted with the inclusion of use of a surrogate FRAX tool specific for Pakistan. One recommendation regarding vitamin D dosage was adapted to recommend a dose of 2000-4000 IU of vitamin D in patients with obesity, malabsorption, and old age. The developed Pakistani postmenopausal osteoporosis guideline consists of 50 recommendations. The guideline created recommends a higher dose (2000-4000 IU) of vitamin D for patients who are old, have malabsorption, or are obese, which is an adaptation from the SG by the AACE. This higher dose is justified as lower doses prove to be suboptimal in these groups and should be complemented with baseline vitamin D and calcium levels.

Thirty-Day Morbidity and Mortality After Total Knee Replacement in a Tertiary Care Hospital in Pakistan.

Background Total knee arthroplasty has become very popular globally as a safe surgical modality for relieving pain and improving functional outcomes in patients who fail to respond to conservative treatments; however, it may be associated with postoperative complications. The aim of this study is to determine the incidence of postoperative complications occurring within the first 30 days after total knee replacement (TKR). Materials and methods This is a prospective cross-sectional study. All consecutive patients who underwent primary unilateral or bilateral total knee arthroplasty between November 2020 and July 2021 were included in the study. Patients were followed for a period of 30 days, and postoperative complications (if any) were documented. Continuous variables were expressed as means ± standard deviations. Categorical variables were expressed as frequency and percentages, and chi-square test was used to compare the qualitative variables. Univariate and multiple logistic regression analyses were done to analyze the magnitude of associations of the complication with other predictor variables keeping a level of significance of <0.05. Results The overall complication rate within the 30-day window was 7.0%. Postoperative surgical site infections (SSI) were noted in three patients (2.6%). Thromboembolic complications were seen in only one patient (0.9%). One patient (0.9%) was readmitted within the one-month period after initial discharge, and one patient (0.9%) expired within 12 hours postoperatively. Conclusion TKR renders satisfactory results with a low incidence of complications in general; however, wound infections, thromboembolic complications, and cardiovascular complications do occur postoperatively. Male gender, obesity, and bilateral TKRs remain the notable risk factors for the development of complications post-procedure.

Do's and Don'ts in Primary Aneurysmal Bone Cysts of the Proximal Femur in Children and Adolescents: Retrospective Multicenter EPOS Study of 79 Patients.

BACKGROUND: Aneurysmal bone cysts (ABC) are rare benign cystic bone tumors, generally diagnosed in children and adolescents. Proximal femoral ABCs may require specific treatment strategies because of an increased pathologic fracture risk. As few reports are published on ABCs, specifically for this localization, consensus regarding optimal treatment is lacking. We present a large retrospective study on the treatment of pediatric proximal femoral ABCs. METHODS: All eligible pediatric patients with proximal femoral ABC were included, from 11 tertiary referral centers for musculo-skeletal oncology (2000-2021). Patient demographics, diagnostics, treatments, and complications were evaluated. Index procedures were categorized as percutaneous/open procedures and osteosynthesis alone. Primary outcomes were: time until full weight-bearing and failure-free survival. Failure was defined as open procedure after primary surgery, >3 percutaneous procedures, recurrence, and/or fracture. Risk factors for failure were evaluated. RESULTS: Seventy-nine patients with ABC were included [mean age, 10.2 (±SD4.0) y, n=56 male]. The median follow-up was 5.1 years (interquartile ranges=2.5 to 8.8).Index procedure was percutaneous procedure (n=22), open procedure (n=35), or osteosynthesis alone (n=22). The median time until full weight-bearing was 13 weeks [95% confidence interval (CI)=7.9-18.1] for open procedures, 9 weeks (95% CI=1.4-16.6) for percutaneous, and 6 weeks (95% CI=4.3-7.7) for osteosynthesis alone ( P =0.1). Failure rates were 41%, 43%, and 36%, respectively. Overall, 2 and 5-year failure-free survival was 69.6% (95% CI=59.2-80.0) and 54.5% (95% CI=41.6-67.4), respectively. Risk factors associated with failure were age younger than 10 years [hazard ratios (HR)=2.9, 95% CI=1.4-5.8], cyst volume >55 cm 3 (HR=1.7, 95% CI=0.8-2.5), and fracture at diagnosis (HR=1.4, 95% CI=0.7-3.3). CONCLUSIONS: As both open and percutaneous procedures along with osteosynthesis alone seem viable treatment options in this weight-bearing location, optimal treatment for proximal femoral ABCs remains unclear. The aim of the treatment was to achieve local cyst control while minimizing complications and ensuring that children can continue their normal activities as soon as possible. A personalized balance should be maintained between undertreatment, with potentially higher risks of pathologic fractures, prolonged periods of partial weight-bearing, or recurrences, versus overtreatment with large surgical procedures, and associated risks. LEVEL OF EVIDENCE: Level IV, therapeutic study.

An Audit of the effect of Bone Morphogenetic Protein-2 Treatment in patients with non-union of long bone fractures.

OBJECTIVE: To evaluate the outcomes, clinical and radiological application of Bone Morphogenetic Protein-2 alone versus Bone Morphogenetic Protein-2 with autograft in long bone non-unions. METHODS: A prospective review of patients was done with fracture non-union admitted to Aga Khan University Hospital, Karachi, from January 2016 to January 2019. The patients were divided into two groups; those exposed to Bone Morphogenetic Protein-2 alone in group 1, and those exposed to Bone Morphogenetic Protein-2 plus autologous graft in group 2. RESULTS: Background characteristics of both the groups were analysed. Patients were followed up at 6, 12 and 24 weeks through their medical records. The primary outcome was postoperative union at 6, 12 and 24. Union was defined by having the clinical union as well as the radiological union at the same time of assessment. Of the 80 patients enrolled, 13(16.25%) were excluded, and 5(6.25%) were lost to follow-up. The final sample had 62(77.5%) patients; 35(56.5%) in group 1, and 27(43.5%) in group 2. Union at 6 weeks was observed in 13(21%) patients; 8(62%) in group 1, and 5(38%) in group 2. Union at 12 weeks was observed in 38(61%) patients; 20(53%) in group 1, and 18(47%) in group 2. CONCLUSIONS: Results showed that using the adjuvant treatment alone was not worse than using it along with bone autologous graft.

Our experience of Mega-prosthesis in bone tumours: A retrospective cross-sectional study in a tertiary care hospital.

OBJECTIVE: To evaluate the oncological and functional outcomes of bone tumour patients who underwent reconstruction with mega prosthesis. METHODOLOGY: A retrospective study was conducted in the department of Orthopaedics Aga Khan University Hospital, Karachi. All the paediatric and adult age group patients diagnosed with malignant, benign and metastatic bone tumours and meeting the inclusion criteria were selected and analysed. Retrospective data was collected from January 2008-January 2018. RESULTS: Sixty-two patients, 30 (48.4%) females and 32 (51.6%) males. were included in the study. Of these 57 (92%) cases had involvement of the lower limb. The mean age was 36.95±19.1 years with a range of 9-81 years. The duration of patients follow up was from 1-124 months (mean 32.7±36.43 months). There were 29 (47%) malignant cases. The most commonly occurring tumour site was distal femur and proximal femur. There were 53 (85%) primary surgeries (first time conducted surgeries) while 9(15%) revision surgeries were done. Major complications were encountered in 19 (30.6%) patients and 13 (20.9%) had minor complications. Post-surgery local recurrence occurred in 2 (3.2%) patients while 7 (11.2%) had distant metastasis. In functional outcomes the mean MSTS score of our patients was 72.09±26.43. The survival rate was 69.8% with 45 patients recovered. CONCLUSIONS: With a good patient selection, adherence to the principles of tumour surgery and an adequate applied knowledge of mega prosthesis insertion, a good functional outcome was achieved.

Treatment and outcomes of soft tissue sarcoma of groin, hip and thigh: a retrospective review from a tertiary care hospital.

OBJECTIVE: To study the frequency of the thigh, hip and groin soft tissue sarcomas and retrospectively analyse the management, treatment results, and outcomes of these uncommon malignant tumours, in a tertiary care hospital of the city of Karachi. METHODOLOGY: Data of soft tissue tumours registered from 2017-2018 was retrieved during January 2019 to March 2019 from Aga Khan University Hospital, Karachi bone and soft tissue tumour registry. A retrospective review was performed and all soft tissue tumour cases treated with surgical intervention (with adjuvant /neoadjuvant therapy) or palliative intention were included. RESULTS: Total 119 cases of soft tissue tumours (STS) were identified out of which 85 were malignant cases (sarcomas) while 30 were benign. On presentation 84 (70.6%) were primary cases. On topographical distribution, there were 25 patients who had hip, groin and thigh sarcoma. Of these, 15 were males and 10 were females. As treatment, neo-adjuvant radiation was done in 4 (16%) patients and adjuvant chemo/radio therapy was given to 13 (52%) patients. Wide margin excision was performed in 19 (76%) patients and 4 (16%) had amputation. Reconstruction was offered to 3 (12%) patients. In post-surgical complications, 1 (4%) patient had wound infection. On final surgical histopathology, majority of the sarcomas were liposarcomas, myxofibrosarcoma, synovial sarcoma and Leiomyosarcoma. Post-surgery recurrence occurred in 7 (28%) patients. Overall survival was 76%. CONCLUSIONS: In treatment of soft tissue sarcoma, limb salvage is an achievable option and survival results are also good.

Outcome of percutaneous screw fixation of posterior pelvic ring injuries.

OBJECTIVE: To evaluate the clinical outcome of percutaneous fixation for unstable pelvic ring injury. METHODS: This retrospective study was conducted at orthopaedics section of Aga Khan University Hospital Karachi, Pakistan from July 2015 to December 2018. Data was retrieved from trauma registry from July 2015 till December 2018, including all patients who underwent percutaneous fixation for pelvic ring injury. Majeed pelvic score was used to determine the functional outcome. RESULTS: A total number of 30 patients were included, 27(90.0%) adults, and 3(10.0%) paediatrics patients. There were 21(70.0%) males and 9(30.0%)females. . Mean age of patients was 37.1±16.1 years. Post op mean Majeed functional pelvic Score was 85.8. Of the 30 patients, 18 (60.0%) had Excellent, 10 (33.3%) good and 02(6.7%) fair scoring. CONCLUSIONS: Percutaneous fixation of posterior ring injuries has excellent functional outcome, with minimal blood loss and no soft tissue striping..

Our experience of treating adult bone lymphoma, A retrospective cross-sectional study in a tertiary care center, Aga Khan University Hospital, Karachi.

OBJECTIVE: To determine the experience at the Aga Khan University Hospital in diagnosing and treating adult patients with primary lymphoma of bone. METHODOLOGY: All patients with Primary lymphoma of bone (PLB) that were diagnosed and/or treated at Aga Khan University Hospital, Karachi from 2005 to 2019 were included as part of this study. RESULTS: There were 17 patients with PLB including 13 (76.5%) males and 4 (23.5%) females with a mean age of 44 ± 16.5 years. Nine patients were between 30-59 years of age at diagnosis. The mean follow-up time of patients was 80±46.7 months. Six patients had tumours of pelvic bone followed by tibia (5) and femur (4). Four patients had a pathological fracture at the time of presentation whereas 2 (11.8%) required surgical fixation of the pathological fracture. The stage of the tumour was based on Ann Arbor classification. Nine (52.9%) cases had Stage 1 disease, 7 (41.2%) had stage IV disease with metastasis in extra nodal tissues. As for treatment, every patient received chemotherapy whereas 5 (29.4%) received adjuvant radiotherapy. Complete remission in the size of the tumour was seen in 11 (64.7%) patients while 6 (35.3%) had partial remission. Post-treatment, 4 (23.5%) patients expired. The mean Overall Survival (OS) time was 80.18 ± 46.71months with a survival rate of 76.5. CONCLUSIONS: Primary lymphoma of the bone can be treated with medical regime and good prophylactic surgeries to avoid pathological fracture such as intramedullary nailing.

Functional outcomes and complications of total hip arthroplasty with dual mobility cup : an audit.

OBJECTIVE: To determine the functional outcomes in total hip arthroplasty with a dual mobility cup, performed in our hospital. METHODS: After receiving an exemption from the Ethics review committee of the hospital, data collection for audit was started in January 2019. Records from July 2016 to June 2018 were included. All patients who underwent total hip arthroplasty with dual mobility prosthesis without any age limit were included. A proforma was prepared to collect the required information. Data was entered and analyzed on SPSS v. 21. RESULTS: Two hundred and ten patients were included, 114 females and 96 males. Of the total, 188 patients underwent unilateral surgery while 22 had bilateral hip arthroplasty. The mean postoperative hospital stay was 5.91±3.9 days. . Mean pre-op Harris score was 33.7±7.6 and the post-op mean score was 75.9± 5.34. Eighty-three (39.5 %) patients had the neck of femur fracture, 31(14.8%) had osteoarthritis while 28(13.3%) had avascular necrosis. Post-surgery complications included, wound infection, surgical site haematoma, NSTEMI, and only one patient reported dislocation after use of dual mobility cup. CONCLUSIONS: The dislocation rate which was the prime concern, has been reduced with the use of dual mobility implant in total hip arthroplasty patients.

Long-term functional outcomes after total scapulectomy with dual suspension reconstruction in children - A case series.

Implant reconstruction following scapulectomy in children is a challenging task. Dual suspension reconstruction may offer an alternative but there is a dearth of literature on functional outcomes following this procedure for malignant tumours in children. A retrospective study was conducted at the Aga Khan University Hospital, a tertiary care centre in Karachi, Pakistan. Children with malignant tumours of the scapula who underwent total scapulectomy with dual suspension reconstruction (n=5) between Jan 2009 and June 2015 were included. Mean follow up was 50±13.39 months. There were four boys and one girl having mean age of 11±3.57 years. All patients were Enneking Stage IIB with 4 patients diagnosed as Ewing's Sarcoma and 1 as osteosarcoma. The MSTS scores ranged from 20-25 points, with a median of 23. One patient developed postoperative surgical site infection requiring surgical debridement whereas all patients remained disease-free till last follow up. Our findings suggest that scapulectomy with dual suspension reconstruction achieves satisfactory functional results with low rate of complications.

Strengthening Orthopaedic care at national level: Output of a structured residency programme at Aga Khan University.

This descriptive review of the output of the orthopaedic residency programme of Aga Khan University, Karachi, comprised information regarding the number of graduated residents and their educational background which was retrieved from departmental records. Information about their work location, subspecialty, current working status, participation in medical camps and national disaster relief efforts were obtained from various sources, including fellow surgeons, and social media profiles. From 1989 to 2017, a total of 48 residents graduated from the programme, with only 2(4.2%) of them being females. Overall, 19(39.6%) residents hailed from areas outside Karachi; 28(58.3%) belonged to Karachi; 1(2%) came from Kenya; 41(85.4%) remained to serve in Pakistan working mostly in tertiary healthcare centres; and 7(14.6%) moved abroad on consultancy and teaching assignments. Subspecialty training had a general trend towards general orthopaedics and trauma 21(43.7%), followed by arthroplasty surgery 13(27%).

Musculoskeletal tumours throughout history and beyond: Clinical features, imaging, staging and biopsy.

BACKGROUND: Over the last century, there has been a remarkable development in the study of bone and soft tissue sarcomas. This is primarily due to the improved knowledge of the nature of these lesions and the improved imaging technology. In literature there are many protocols that are being used and all of them have reported various advantages and disadvantages of each technique used. However, there is no set guideline and whatever has been proposed has been developed on the basis of the experience of different centres and different surgeons. OBJECTIVE: The current systematic review was planned to thoroughly evaluate the levels of evidence on which we base decisions for surgical management of lower extremity bone tumours. METHODS: The review included descriptive studies published in the English language. Studies included case reports, case series and experiences of different centres for the surgical management of lower extremity bone tumours. Articles reporting all levels of evidence - Level I to V - were included. PubMed, ERIC, MEDLINE, EMBASE and Cochrane Reviews databases from 2002 to 2012 were searched. RESULTS: Information was gathered and thoroughly studied from 63 articles. There were no Level I studies, 2(3.2%) Level II studies, 47(74.6%) Level III, and the remaining 14(22.2%) studies were Level IV and Level V. CONCLUSIONS: Sarcomas are rarely occurring neoplastic conditions which are present in all age groups but commonly affect young age population. Most are asymptomatic but can present with pain or pathological fracture. These lesions are commonly diagnosed with plain radiographs. CT scan and MRI may be used to delineate anatomy and to quantify the extent of soft tissue involvement. Various advantages and disadvantages associated with each aspect in the management of patients starting from the basic history-taking, physical examination, imaging, biopsy principles, peri-operative laboratory work-up and staging of the cancer were studied. Treatment ranges from conservative to en-block resection including extended curettage. Aggressive tumours should be closely followed up for recurrence and metastasis.

Outcome of proximal femur replacement in failed internal fixation of hip fractures, a case series.

INTRODUCTION: Failure of hip implant surgeries can be caused by various factors. Failure of internal fixation results in pain and restricted ambulation. In management of an elderly patient with hip fractures, the aim is to ambulate patient. The purpose of our study is to assess the outcomes of proximal femur replacement in the management of failed hip surgeries for fractures of the proximal femur. MATERIALS AND METHODS: A retrospective analysis of 26 patients, who underwent proximal femur replacement for failed surgeries of hip fracture during the period from April 2011 to March 2018, was conducted. All patients who underwent proximal femur replacement for failed hip implants were enrolled into the study. RESULTS: Total patients were 26. The mean follow was (12-91 months). The mean Harris Hip score improved from 26 preoperative to 66.7(45-91). Three patients developed dislocations which were managed with closed reduction. Three patients died within one year of surgery, one patent died of sepsis from implant infection at four months after surgery, one patient died of Myocardial infarction. Three patients developed surgical site infection of which one has superficial surgical site infection which was managed with oral antibiotics, in other case developed deep surgical site infection and was managed with wound debridement and IV antibiotics for 6 weeks, in third wound debridement was done but patient died of sepsis. CONCLUSION: Proximal femur replacement with modular stem implant has advantages over conventional hip implant in patients undergoing surgery after failure of internal fixation.

Histomorphometric Analysis of Pre- and Post-Denosumab-Treated Giant Cell Tumor of Bone.

Context. Denosumab is a monoclonal antibody against RANK ligand. Its administration in giant cell tumor of bone (GCTB) cases results in elimination of giant cells and new bone formation. Neoplastic stromal cells of GCTB harbor mutation of histone 3.3 and have pre-osteoblastic properties and thus express SATB2. Objectives. To (1) analyze histological changes in post-denosumab-treated GCTB, (2) analyze expression of H3.3G34W and SATB2 in pre- and post-denosumab-treated samples, and (3) to discuss why changes occur in the expression of not only H3.3G34W but also SATB2. Materials and Methods. Hematoxylin and eosin slides of 19 cases of denosumab-treated GCTB were reviewed. Immunohistochemical stains H3.3G34W and SATB2 were performed. The number of positive mononuclear cells were counted and graded. Results. Complete absence of osteoclast-like giant cells (OCLGCs) was noted in most cases along with a fibro-osseous component merging with peripheral shell of reactive bone. Irregular trabeculae of woven bone and osteoid with focal osteoblastic rimming was seen. Spindle cells were arranged predominantly in fascicular pattern. Morphometric analysis of H3.3G34W showed a mean of 68.8% positive stromal cells in pretreatment and a mean of 26.9% positive stromal cells in posttreated specimens with a statistically significant P value (.001). Mean percentage of SATB2-positive stromal cells in the pre- and posttreatment specimens was 36.46% and 20.8%, respectively. Conclusions. Our study validates that denosumab treatment results in marked reduction of OCLGCs with increased osteoblastic activity. Decreased expression of H3.3G34W in posttreatment may be a result of decreased antigenicity of neoplastic mononuclear cells. No significant change in SATB2 expression was noted.

Spectrum of histological features of Denosumab treated Giant Cell Tumor of Bone; potential pitfalls and diagnostic challenges for pathologists.

OBJECTIVES: Denosumab is Receptor Activator of Nuclear factor Kappa-B Ligand (RANKL) inhibitor which is being used in the treatment of locally advanced, recurrent and metastatic Giant Cell Tumor of Bone (GCTB). It causes reduction in monocyte recruitment and Osteoclast-Like Giant Cell (OLGC) formation which limits bone destruction. After Denosumab treatment, GCTB exhibit diverse morphological features which can pose diagnostic challenge. Our aim was to study the spectrum of histologic features seen in Denosumab treated GCTB which could be helpful in establishing correct diagnosis. METHODS: We retrieved and reviewed H&E stained microscopic glass slides of 38 GCTB cases who received Denosumab as neoadjuvant treatment. These cases were treated at different institutes and diagnosed at our institute between January 2017 and October 2019. Morphologic features such as presence of residual OLGC, appearances of mononuclear stromal and bony components were assessed along with other non-specific features. RESULTS: Patients' median age was 29 years. Male to female ratio was 1.53:1. Femur was the most commonly involved bone. Microscopically, peripheral shell of reactive bone was observed in all cases. In 20 (52.6%) cases, there was complete elimination of OLGC. Mononuclear stromal cells were predominantly bland spindle shaped and arranged in fascicular and storiform patterns. Focal atypia was noted in 3 cases. Bony component manifested as trabeculae of woven bone with osteoblastic rimming and immature trabeculae of unmineralized osteoid with haphazardly present osteoblasts. Spectrum of stromal changes included cystic spaces, foamy macrophages, inflammatory infiltrate, hemangiopericytoma-like (HPC-like) vessels, hyalinization, edematous areas and hemosiderin pigment. The tumors showed areas which resembled other bony and soft tissue lesions such non-ossifying fibroma, fibrous dysplasia, osteoblastoma, sclerosing epithelioid fibrosarcoma and osteosarcoma. CONCLUSION: Denosumab treatment induces a variety of changes in GCTB. Clinical history and knowledge of these features are necessary for excluding differential diagnoses and avoiding misdiagnosis.

A comprehensive basic understanding of pelvis and acetabular fractures after high-energy trauma with associated injuries: Narrative review of targeted literature.

Acetabular fractures are caused by energy trauma which is high enough to cause such a fracture with incidence of 3 patients / 100000. In older individuals, most commonmechanism of injury is fall and, in younger individuals, road traffic accidents. Acetabular fractures are usually associated with visceral injuries and other musculoskeletal injuries (about 50% of patient). In this narrative review of targeted English literature from all level of evidences, which is written and supervised by experienced specialized orthopedic and trauma surgeons who were among the pioneers of conducting pelvis fracture management workshops in the country, we aim to describe the mechanism of injury, assessment principles and associated injuries, decision-making and preoperative planning and indications of non-operative managements.