Prognostic factors and real-life applicability of prognostic models for patients with bone metastases of carcinoma.

OBJECTIVE: This study aimed to investigate the factors affecting the survival of patients with bone carcinoma metastases and assess the clinical applicability of existing prognostic models. METHODS: We retrospectively evaluated 247 patients who presented to our hospital between 2011 and 2021 diagnosed with bone carcinoma metastasis. Demographic data, general health status, primary diagnoses, laboratory and radiological findings, pathological fracture status, treatment methods, and survival times of the patients were recorded, and the effects of these variables on survival time were evaluated. Previously developed Katagiri, Janssen, 2013-Spring, PathFX, and SORG prognostic models were applied, and the predictive performances of these models were evaluated by comparing the predicted survival time with the actual survival time of our patients. RESULTS: After the multivariate analysis, the following factors were shown to be significantly associated with the survival time of patients: blood hemoglobin and leukocyte levels, lactate dehydrogenase concentration, prognostic nutritional index, body mass index, performance status, medium and fast-growing groups of primary tumors, presence of extraspinal and visceral or brain metastases, and pathological fractures. According to receiver operating characteristics and Brier scores, SORG had the overall highest performance scores, while the Janssen nomogram had the lowest. CONCLUSION: Our report showed that all prognostic models were clinically applicable, but their performances varied. Among them, the SORG predictive model had the best performance scores overall and is the model the authors suggested for survival prediction among patients with carcinoma bone metastases. LEVEL OF EVIDENCE: Level IV, Prognostic Study.

Combined Lumbar-Sacral Plexus Block in Facioscapulohumeral Muscular Dystrophy for Hip Fracture Surgery: A Case Report.

Facioscapulohumeral muscular dystrophy (FSHD) is a muscular dystrophy that can affect individuals of all age groups. Its prevalence is reported to be 0.4-1 in 10,000 people. Because of the low occurrence of FSHD, anaesthetic management is primarily based on expert opinions, case reviews, or brief series. Here, we present the case of a 72-year-old woman with FSHD who underwent hip fracture (HF) surgery. To prevent respiratory compromise due to FSHD, we opted for lumbar-sacral plexus block. To the best of our knowledge, there is no information in the literature regarding the use of combined lumbar-sacral plexus block in patients with FSHD undergoing HF surgery.

Reconstruction of critical size segmental femoral diaphyseal defects of New Zealand rabbits by using combined titanium mesh cage and induced membrane technique.

PURPOSE: Long bone defects due to fractures resulting from high-energy trauma, infections and tumor resections are problems that orthopedic surgeons commonly face. We investigated the effects of a titanium mesh cage on bone healing with an induced membrane technique. METHODS: Three groups, each composed of eight rabbits, were formed. Extraarticular diaphyseal bone defects were created. Femora of the first group were fixed with an empty titanium mesh cage and two K-wires. After formation of the defect, polymethylmethacrylate was inserted and fixed with a K-wire in the second group. At the third week, the cement was removed, a sterilized cancellous graft-filled titanium mesh cage was placed into the defect, and the membrane that was previously formed over the cement was placed on the cage and repaired. In the third group, sterilized cancellous grafts were filled into the titanium mesh cage, and the titanium mesh cage was fitted into the bone defect area. RESULTS: At the end of the third month, all subjects were killed. Radiological data revealed that the healing of the bone in the second and third groups was significantly better than that in the first group. There was no difference between the second and third groups. A histological evaluation of the healing status, such as fibrous tissue, cartilage tissue and mature or immature bone formation, was performed. Histological healing in the second and third groups was also significantly better than that in the first group. CONCLUSION: We concluded that the combination of membrane-induced bone healing and graft-filled titanium mesh cages expedites osteogenesis in extraarticular bone defects.

Clinical and radiological outcomes of Salter versus Pemberton osteotomies in the management of developmental dysplasia of the hip: A retrospective comparative study.

OBJECTIVE: The aim of this study was to investigate whether there is a relationship between Salter and Pemberton pelvic osteotomies and avascular necrosis of femoral head in the management of developmental dysplasia of the hip (DDH). METHODS: This retrospective study included 69 hips of 52 patients aged between 12-36 months, diagnosed as DDH who had undergone either Salter or Pemberton pelvic osteotomy with Smith Petersen approach. There were 35 patients in Salter Pelvic Osteotomy and 34 patients in Pemberton Pelvic Osteotomy groups. Before the treatment of DDH, Tönnis classification was used, preoperative and 24th month postoperative Acetabular Index (AI) angles were measured. Kalamchi-MacEwen grades of avascular necrosis were determined in terms of presence of avascular necrosis of the femoral head. RESULTS: There were no significant differences between two osteotomy groups at the end of mid-term follow up in terms of the radiological parameters and avascular necrosis of femoral head. However it was found that the increased avascular necrosis incidence was significantly associated with Tönnis grade 4 hips. CONCLUSION: Salter and Pemberton osteotomies can be both used safely in the treatment of DDH regarding their effect on the femoral head. LEVEL OF EVIDENCE: Level III, Therapeutic Study.

Preliminary results of a new intercalary modular endoprosthesis for the management of diaphyseal bone metastases.

OBJECTIVES: This study aims to evaluate functional outcomes of patients and to analyze complication rates of modular intercalary endoprosthetic reconstruction after resection of metastatic diaphyseal bone lesions. PATIENTS AND METHODS: Between December 2017 and February 2020, 22 patients (15 males, 7 females; median age: 64.2 years; range, 49 to 91) who underwent reconstruction with modular intercalary endoprostheses for metastatic bone tumors at five different centers were retrospectively analyzed. Age, sex, diagnosis, follow-up duration, previous treatments of patients, and resection lengths were recorded. The Musculoskeletal Tumor Society Scores (MSTS) were used to assess functional status of available patients at the final follow-up. Failures were categorized according to the Henderson classification. RESULTS: Locations of the resected tumors included 10 humeri (45.5%), five tibiae (22.7%), and seven femurs (31.8%). The length of the resected tissues ranged from 35 mm to 180 mm. Seven patients (31.8%) died of disease, and one patient died of pneumonia within follow-up period. The functional outcomes of surviving patients were satisfying with a median MSTS score of 86.9% (range, 70 to 100%) at a median follow-up of 17 (range, 8 to 26) months. There were two cases of type II (9%), one cases of type IIIa (4.5%), two cases of type IIIb (9%), and one case of type IV (4.5%) failure. Complications were most commonly observed in tibial reconstructions. CONCLUSION: The good short-term functional results were achieved in surviving patients. Uncomplicated patients were able to perform daily living activities without limitations. The overall rate of complications was relatively low and, among them, mechanical problems were the most commonly encountered problems.

Cross-cultural adaptation and validation of the Turkish version of the Toronto Extremity Salvage Score in patients with musculoskeletal tumors.

OBJECTIVE: The aim of the study was to translate theToronto Extremity Salvage Score (TESS) into Turkish and perform acrosscultural adaptation for patients with musculoskeletal tumors. METHODS: Thirty-six patients (20 male, 16 female; mean age = 36.6 ± 15.4 years) who were diagnosed with malignant bone and soft tissue sarcoma or benign aggressive bone tumors between the years 2007 and 2012 were included in the study. TESS was translated into Turkish and back translated to determine language validity. To test convergent validity, the Turkish versions of the Short Form-36 (SF-36), Western Ontario and McMaster Universities Arthritis Index (WOMAC), and Disabilities of the Arm, Shoulder and Hand (DASH) were used. SF-36 was used on all patients while WOMAC and DASH were used onpatients with lower extremity tumors and upper extremity tumors respectively. The tests were repeated 15 days later and the intraclass correlation coefficient (ICC) was used to determine test-retest reliability. RESULTS: The Turkish version of TESS was found to have a strong negative correlation with WOMAC (r = -0.702; P < 0.001) and DASH (r = -0.774; P < 0.001) as well as a strong negative correlation with ROMS (r = 0.601; P < 0.001). Turkish TESS also had a statistically significant correlation with SF-36-Physical functioning, SF-36-Role Physical, SF-36-Bodily Pain, and SF36-General Health at levels ranging from 0.326 to 0.669 (r values ranging from 0.326 to 0.669, P < 0.001). The internal consistency (Cronbach's α:0.96 for lower extremity and Cronbach's α:0.94 for upper extremity) and test-retest reliability of Turkish TESS were found to be excellent (ICC lower extremity: 0.96 [0.935-0.983]; P < 0.001 and ICC upper extremity: 0.99 [0.967-0.997]; P < 001). ICC values varied between 0.674 and 0.987 for each item of the scale for both extremities. Conlusion: The Turkish version of TESS seems to be a valid and reliable patient-reported outcome measure to evaluate physical function after musculoskeletal tumor surgery in Turkish patients. LEVEL OF EVIDENCE: Level II, Diagnostic Study.

Ultrasonographic measurement of the dimensions of proximal and distal patellar fragments after Niebauer-King Procedure for the management of congenital dislocation of the knee.

OBJECTIVE: The aim of this study was to ultrasonographically measure the dimensions of the proximal and distalpatellar fragments to determine whether postoperative growth differences existbetween the fragments in children with congenital dislocation of the kneetreated by Niebauer Kings quadricepsplasty. METHODS: This retrospective study included six congenitaldislocated knees of four children with arthrogryposis multiplex congenita (AMC)(3 girls; mean age = 40 months; age range = 9-44 months), presented with severe hyperextension knee contractures,which were treated by Niebauer-King's quadricepsplasty.The transverse, craniocaudal, and anteroposterior dimensions of the patellaewere measured ultrasonographically 20 (range = 6-42) months postoperatively by a singleradiologist. RESULTS: The mean transverse, craniocaudal, and anteroposteriordimensions of proximal and distal halves of the patellae were: 11.46 (7.0-16.9)-10.5 (8.0-14.4); 17.4 (14.0-21.0) -16.68 (14.5-19.3); 6.76 (5.6-7.9) -7.76 (7.0-9.4) mm respectively. There was no significantdifference in craniocaudal and transverse dimensions, but the anteroposteriordimension (thickness) of the distal patellae articulating the knee joint had agreater thickness (P = 0,01). CONCLUSION: Evidence from this study has shown that a bettergrowth can be expected in the distal fragment of the patella compared with theproximal fragment following treatment with Niebauer-King's quadricepsplasty in children with congenital dislocation ofthe knee. LEVEL OF EVIDENCE: Level IV, Therapeutic Study.

Cross-cultural adaptation and validation of the Turkish version of the Musculoskeletal Tumor Society scoring system in patients with musculoskeletal tumors.

OBJECTIVE: This study aimed to translate and cross-culturally adapt the musculoskeletal tumor society (MSTS) scoring system into Turkish and to determine the reliability and validity of the translated version for the functional evaluation of patients with musculoskeletal tumors. METHODS: A total of 36 patients (16 women, 20 men; mean age=36.6; age range=13-75 years) who underwent limb-salvage surgery owing to benign aggressive or malignant musculoskeletal tumors were included in the study. Translation and back translations of the MSTS were performed according to the published guidelines. Short form (SF) 36 physical component, Western Ontario and McMaster Universities Arthritis Index (WOMAC), disabilities of the arm, shoulder, and hand (DASH), and range of motion scale (ROMS) that were previously analyzed for Turkish validation were used for validity. Reliability of MSTS Turkish version was evaluated by calculating test-retest reliability and internal consistency. Intraclass correlation coefficient (ICC) was used to evaluate the inter-observer consistency and test-retest reliability. Alpha coefficient (Cronbach's alpha) was used to evaluate the internal consistency. RESULTS: It was observed that total MSTS score has a strong negative correlation with DASH (r=-0.689; p<0.001) and WOMAC scores (r=-0.634; p<0.001) and moderate correlation with the ROMS score (r=0.521; p<0.001). Total MSTS score also had a statistically significant strong correlation with SF-36 scores (r values ranging from 0.425 to 0.609, p<0.001). Inter and intra-observer reliability of the MSTS scale was found to be excellent (Cronbach's α=0.97 p<0.001; ICC: 0.97 (0.96-0.99; p<0.001). Unlike other subscales, statistical correlation between dexterity and hand-positioning subscales of MSTS with DASH scores was found to be insignificant (r=-0.533, p =0.061 and r=-0.336, p=0.261, respectively). CONCLUSION: The Turkish version of the MSTS scoring system seems to be a valid and reliable scale that measures the correct and desired values in the evaluation of health-related quality of life in orthopedic oncology. Reliability coefficients of the Turkish version of MSTS were determined to be strong. LEVEL OF EVIDENCE: Level II, Diagnostic Study.

Is elective cancer surgery feasible during the lock-down period of the COVID-19 pandemic? Analysis of a single institutional experience of 404 consecutive patients.

BACKGROUND: We aimed to assess the feasibility and short-term clinical outcomes of surgical procedures for cancer at an institution using a coronavirus disease 2019 (COVID-19)-free surgical pathway during the peak phase of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. MATERIALS AND METHODS: This was a single-center study, including cancer patients from all surgical departments, who underwent elective surgical procedures during the first peak phase between March 10 and June 30, 2020. The primary outcomes were the rate of postoperative SARS-CoV-2 infection and 30-day pulmonary or non-pulmonary related morbidity and mortality associated with SARS-CoV-2 disease. RESULTS: Four hundred and four cancer patients fulfilling inclusion criteria were analyzed. The rate of patients who underwent open and minimally invasive procedures was 61.9% and 38.1%, respectively. Only one (0.2%) patient died during the study period due to postoperative SARS-CoV2 infection because of acute respiratory distress syndrome. The overall non-SARS-CoV2 related 30-day morbidity and mortality rates were 19.3% and 1.7%, respectively; whereas the overall SARS-CoV2 related 30-day morbidity and mortality rates were 0.2% and 0.2%, respectively. CONCLUSIONS: Under strict institutional policies and measures to establish a COVID-19-free surgical pathway, elective and emergency cancer operations can be performed with acceptable perioperative and postoperative morbidity and mortality.

Retrorectal tumor: a single-center 10-years' experience.

PURPOSE: Retrorectal tumors (RTs) are a rare incidence and recommendations on the ideal surgical approaches are lacking. This study aimed to evaluate outcomes and follow-up results of patients undergoing excision of RTs at our institution. METHODS: A retrospective review was conducted for undergoing surgery for RT between January 2009 and January 2019. Demographic characteristics, presenting symptoms, preoperative diagnostic tests, surgical procedures, histopathological results, intraoperative and postoperative complications, postoperative hospital stay, postoperative 30-day mortality, 90-day unplanned readmission rate, and long-term outcomes were evaluated. RESULTS: Twenty patients with a mean age of 48.3 ± 14.2 were analyzed. The most common presenting complaint was perineal pain (35.0%). Magnetic resonance imaging and computed tomography was preferred in 18 and 2 patients, respectively. Tumor localization was below the level of the third sacral vertebrae in 14 patients for whom the posterior surgical approach was used. No postoperative mortality was recorded at the end of follow-up of 53.8 ± 40 months. Mean length of postoperative hospital stay was 8.6 ± 9.4 days. Ten percent of the patients had unplanned hospital readmission within 90 days after discharge. Recurrence developed in 1 patient, for whom pathology were reported as chordoma. CONCLUSION: RT should be managed by a multidisciplinary team given the complexity and heterogeneity of these tumors despite the fact that the majority are benign. A good understanding of pelvic anatomy and characterization of lesions through detailed radiological imaging is crucial to optimize surgical planning. Complete surgical resection is key for prolonged disease-free and overall survival of patients diagnosed with RTs.

Therapy-Induced Neural Differentiation in Ewing's Sarcoma: A Case Report and Review of the Literature.

Ewing's sarcoma (ES) is a small round cell tumor of adolescents or young adults that usually arises in the deep soft tissues of the extremities. The tumor cells have uniform round nuclei, fine powdery chromatin and indistinct nucleoli. CD99 (O13) is a product of the MIC 2 gene that is highly sensitive to ES but not specific. A panel of markers should be used for the differential diagnosis of small round cell tumors because nearly all others, on occasion, show membranous staining for CD99. One of the defining feature of ES is the presence of 22q12 gene rearrangement. The presented case is a 6 year-old boy complaining of swelling on his right leg. The biopsy was compatible with classic ES in terms of histopathological, immunohistochemical and cytogenetic criteria. Wide surgical resection was performed after chemotherapy. The posttreatment specimen was composed of uniformly small round cells mixed with areas of ganglion cells embedded in neurophil-like fibrillary background. Immunohistochemically, neoplastic cells revealed strong CD99 (O13) and NSE staining and the tumor had EWSR1 gene rearrangement. Morphologic alterations due to treatment are commonly seen in pediatric tumors. Single case reports have defined neural differentiation in ES but to the best of our knowledge this is the first report of ES in the literature with all histopathological, immunohistochemical, and cytogenetic criteria evaluated in both pretreatment and posttreatment specimens.

Evaluation of plantar pressure distributions in patients with anteriorcruciate ligament deficiency: preoperative and postoperative changes.

BACKGROUND/AIM: Anterior cruciate ligament (ACL) deficiency results in several kinematic changes in the lower extremities. The aim of this study is to define the plantar pressure parameters in ACL-deficient patients and to show the effect of ACL reconstruction on dynamic plantar pressure. MATERIALS AND METHODS: Forty patients with unilateral ACL rupture and 40 healthy controls were included in this study. Dynamic plantar pressures of both groups were recorded by the EMED SF-2 system during level walking. Thirteen of the patients who had ACL reconstructions with hamstring autografts (HS group) were reevaluated at an average of 14.5 months following the ACL reconstructions. RESULTS: ACL-deficient patients had significantly lower hindfoot (P = 0.007) but higher midfoot pressure values (P = 0.03) on their ipsilateral foot compared to control group subjects. Ipsilateral hindfoot pressures were also found to be significantly lower than those of the contralateral foot (P = 0.001). Hindfoot pressure values of the HS group were increased in postoperative measurements (P = 0.01). CONCLUSION: ACL-deficient patients have altered plantar pressure distributions and ACL reconstructions restore these changes to normal. Pedobarography might be used as a practical method for dynamic functional assessment of ACL-deficient patients.

Treatment of post-traumatic elbow deformities in children with the Ilizarov distraction osteogenesis technique.

OBJECTIVE: The present study assessed functional and radiographic outcomes of distraction osteogenesis treatment of post-traumatic elbow deformities in children. METHODS: Eight children were treated between 2008 and 2013 for post-traumatic elbow deformities using distraction osteogenesis. Mean age at time of operation was 10.9 years. Six patients had varus and 2 had valgus deformity. Magnitude of correction, fixator index, complications, carrying angle, and elbow range of motion were assessed. Functional results were graded according to protocol of Bellemore et al. RESULTS: Mean follow-up was 43 months. Mean preoperative varus deformity in 6 patients was 29.2° and valgus deformity in 2 patients was 28.5°. Preoperative flexion and extension of elbow were 123.8° and -10.6°, respectively. Mean carrying angle was 9° valgus at last follow-up. Mean flexion and extension were 134.4° and -6.0°, respectively. Change in carrying angle was statistically significant (p = 0.002). There were 2 grade 1 pin tract infections and 1 diaphyseal fracture of humerus. Functional outcome was rated excellent in 7 patients and good in 1 patient. CONCLUSION: Ilizarov distraction osteogenesis is a valuable alternative in treatment of elbow deformities in children. The surgical technique is simple and correction is adjustable. Gradual correction prevents possible neurovascular complications and minimally invasive surgery produces less scarring. Compliance of patient and family is key factor in the success of the outcome. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Elastofibroma dorsi: Clinical evaluation of 61 cases and review of the literature.

OBJECTIVE: Elastofibroma dorsi (ED) is a rare, benign, soft tissue tumor typically located between inferior corner of scapula and posterior chest wall causing mass, scapular snapping, and pain. When classic symptoms and localization are present, it is diagnosed without biopsy and treated with marginal resection. This study retrospectively analyzed patients operated on for ED to evaluate presenting symptoms, tumor size, complications, and clinical results, and to suggest optimal treatments. METHODS: This study included 51 patients who underwent surgery for ED in 2 different clinics between 2005 and 2015. Patient age, gender, profession, side affected, symptoms, average duration of symptoms, and tumor size were researched. Radiological examinations of patients were evaluated. Patients with lesions larger than 5 cm in size were operated on. Postoperative complications, recurrence, and functional results were evaluated using Constant score and compared to preoperative values. RESULTS: A total of 61 operated lesions of 51 patients clinically and radiologically diagnosed with ED were retrospectively evaluated. Average length of time patient experienced symptoms was 11.21 months. Lesions in 19 (37.2%) patients were bilateral, 10 of which were symptomatic and larger than 5 cm in size, meeting indication for surgery. Average lesion diameter was 8.7 cm. Average follow-up was 26.89 months. Average of preoperative Constant score of 67.28 subsequently increased to 92.88 (p < 0.05). Seroma and hematoma were observed in 11.5% of patients. CONCLUSION: Generally, good clinical results can be obtained with marginal resection without requiring a biopsy, considering classic complaints and radiological appearance of ED. LEVEL OF EVIDENCE: Level IV, Therapeutic study.

Clinical and pathological results of denosumab treatment for giant cell tumors of bone: Prospective study of 14 cases.

OBJECTIVE: Giant cell tumor of bone (GCT) is a primary, osteolytic, benign tumor of the bone. Surgery is the commonly used treatment; however, recurrence remains a problem. Receptor activator of nuclear factor kappa B (RANKL) is responsible for the formation of osteoclastic cells. Discovery of RANKL and its human monoclonal antibody, denosumab, led to use of denosumab for treatment of GCT. The aim of this study was to evaluate clinical and pathological results of treatment of GCT with denosumab and to assess adverse effect profile and recurrence rate. METHODS: Thirteen patients with 14 lesions were enrolled in the study. Mean age was 38.3 years. Patients were given subcutaneous injections of denosumab (120 mg) every 4 weeks (with additional doses on days 0, 8 and 15 in cycle 1 only) and were radiologically evaluated for tumor response. Pain and functional status were measured using Visual Analog Score (VAS) and Musculoskeletal Tumor Society Score (MSTS). Adverse effects were analyzed after each cycle. RESULTS: Participants were 5 men and 8 women. Mean follow-up was 17 months. One lesion was Campanacci grade I, 8 were grade II, and 5 were grade III. Eight lesions were recurrent, and remaining were primary lesions. After average of 9 cycles (range: 4-17 cycles), all tumors underwent radiological regression. Ten lesions were removed surgically. More than 90% of giant cells were found to have regressed in all pathological specimens. On last follow-up, average VAS was 1 and MSTS was 87%. Fatigue and joint and muscle pain after injections was reported by 46% of patients, and mild hypocalcaemia was seen in 1 patient. CONCLUSION: Denosumab has been shown to be a successful drug in treatment of GCT. Denosumab can be used as neoadjuvant for all recurrent lesions, grade II lesions with high surgical risk, grade III lesions, and metastatic cases of GCT. LEVEL OF EVIDENCE: Level IV, Therapeutic study.

Comparison of effectiveness of kyphoplasty and vertebroplasty in patients with osteoporotic vertebra fractures.

OBJECTIVE: The aim of this study was to compare the functional and radiological outcomes of vertebroplasty and kyphoplasty in patients with osteoporotic vertebra fractures. METHODS: The files of the patients who underwent vertebroplasty or kyphoplasty for osteoporotic vertebrae fractures were retrieved from the archives. Forty-three patients with complete follow-up data were included in the study group. The patients were evaluated for radiological outcomes in terms of local kyphosis angle, wedging index, compression ratio, visual analog pain scale (VAS) and Oswestry Disability Index (ODI). RESULTS: In the study group, kyphoplasty was performed on 24 vertebrae of 22 patients (17 females, 5 males; mean age: 73 years) whereas vertebroplasty was applied on 24 vertebrae of 21 (16 females, 5 males; mean age: 74.7 years) patients. The mean follow-up time was 26 months. When the VAS and ODI values of the groups were analyzed, both groups showed statistically significant progress after the operation. Radiological data showed that the kyphoplasty group showed statistically significant improvement in the sagittal index values whereas the vertebroplasty group did not. The overall complication ratio was 4%. CONCLUSION: Both vertebroplasty and kyphoplasty are effective treatment methods for functional recovery and pain relief in osteoporotic fractures of the vertebra. Although radiological outcomes of the kyphoplasty seem to be better, this does not have any clinical relevance. We suggest vertebroplasty over kyphoplasty since it is an easier method to manage. LEVEL OF EVIDENCE: Level III, Therapeutic study.

Clinical and prognostic significance of PD-1 and PD-L1 expression in sarcomas.

Programmed death-1 (PD-1) and programmed death-ligand 1 (PD-L1) are new targets in cancer immunotherapy in recent years. The aim of this study is to evaluate the PD-1/PD-L1 expressions in sarcomas and to determine association between PD-1/PD-L1 expressions and clinical/pathological properties in some sarcoma subtypes. Formalin-fixed, paraffin-embedded tissue samples from 65 cases with sarcomas were analyzed. Immunohistochemical staining was performed to detect the PD-1 and PD-L1 expressions in tumor tissue and microenvironment, separately. PD-1 expression in tumor tissue and microenvironment was detected in 11 (17 %) and 8 (12 %) cases, respectively. PD-L1 expression in tumor tissue and microenvironment was detected in 19 (29 %) and 20 cases (30 %), respectively. None of the 5 Ewing sarcomas involving bone showed PD-1/PD-L1 expression, while 2 of 3 cases with Ewing sarcomas involving soft tissue showed PD-1 and PD-L1 expression. Among 5 cases with Kaposi sarcoma, four showed PD-1 and/or PD-L1 expression in tumor or microenvironment. PD-1/PD-L1 expressions were detected 3 of 6 cases with pleomorphic sarcoma, 2 of 4 cases with peripheral nerve sheath tumors and 1 of 4 cases with synovial sarcoma. Interestingly, strongest PD-1/PD-L1 expressions in our study group were detected in 2 sarcoma cases with the history of giant cell tumor. PD-1 and PD-L1 expressions are up to 30 % of the cases with sarcomas. It may be rational to target programmed death pathway in Kaposi sarcoma, pleomorphic sarcoma and peripheral nerve sheath tumors. Strong expression of PD-1/PD-L1 in cases with previous giant cell bone tumor has been found to be interesting and must be studied in giant cell tumor samples.

Morphologic evaluation of the effect of denosumab on giant cell tumors of bone and a new grading scheme.

Giant cell tumor (GCT) is a rare, usually benign but locally aggressive neoplasm. Recent studies suggest new approaches in light of the elucidation of molecular pathways in bone. The osteolytic nature of GCT is caused by the receptor for activating nuclear factor-kB ligand (RANKL) associated osteoclasts. Denosumab is a monoclonal antibody that affects GCT through RANKL and it prevents normal and neoplastic osteolysis. The aim of this study is to evaluate the histopathologic alterations due to denosumab treatment and the efficiency of this drug in GCT therapy. Ten patients had been treated with denosumab and were included in the study. Pretreatment biopsies were interpreted as conventional GCTs and posttreatment biopsies of the ten patients' GCTs were classified in accordance with the grading system. Only one patient had tumor remaining after treatment. There is limited data on histopathologic alterations that follow denosumab treatment. The bone pathologist should keep these changes in mind because they mimic different types of bone tumors. Furthermore, there is no widely accepted grading system to evaluate the effect of denosumab in GCT. Our study suggested a scheme that would be helpful to evaluate the efficiency of denosumab treatment in GCT.

Impact of oxidative stress on early postoperative knee function and muscle injury biochemical markers: Is it possible to create an ischemic preconditioning effect in sequential ischemic surgical procedures?

OBJECTIVE: Simultaneous bilateral total knee arthroplasty (TKA) with prolonged tourniquet time has the potential to trigger ischemia-reperfusion injury, which can adversely affect knee function. Studies suggest that the magnitude of injury is less if it occurs following an ischemic event which takes place in another part of the body, known as ischemic preconditioning (IPC). The purpose of this study was to investigate the impact of oxidative stress on muscle injury and knee function and to elucidate if potential IPC effect can attenuate ischemia-reperfusion injury metabolites and prevent poor functional outcomes in single-stage bilateral TKA. METHODS: Thirty patients who underwent single-stage bilateral TKA under tourniquet were enrolled in the study. All procedures were initiated from the right limb. Upon completion of the procedure, the left tourniquet was inflated 20 minutes after the first tourniquet was deflated. The tourniquet time was noted. Pre- and postoperative levels of malondialdehyde (MDH), creatine kinase (CK), and lactate dehydrogenase (LDH) were evaluated. Knee function was assessed postoperatively at 1 month using WOMAC score. RESULTS: Postoperative levels of MDH, CK, and LDH were significantly increased in both extremities compared to preoperative levels. Serum MDH, CK, and LDH levels were not found to be correlated with tourniquet time for either extremity. Compared to the left extremity, the right extremity revealed increased postoperative oxidative stress, which was indicated by elevated serum MDH, CK, and LDH levels. Although tourniquet time and postoperative serum MDH, CK, and LDH levels were not found to be correlated with WOMAC index in either knee, the average change in WOMAC score at 1 month postoperatively was found to be higher in the left knee compared to the right. CONCLUSION: The biochemical and functional outcomes can be attributed to potential IPC effect. During bilateral TKA, a 20-minute interval between tourniquets can create IPC effect and attenuate the magnitude of ischemia-reperfusion injury, preserving better functional outcomes.

Humeral surface anatomy and percutaneous plate advancement: a cadaveric study.

OBJECTIVE: The aim of this study was to identify the anatomical obstacles on the humeral surface which can complicate subcutaneous plate advancement during surgical treatment of humeral fractures. METHODS: We dissected twelve upper extremities of six male cadavers, and measured the humeral length, which was defined as the distance between the greater tubercle and the lateral epicondyle. We performed a retrograde advancement of a 4.5 mm plate through the subbrachial tunnel and noted the mechanical obstacles during the procedure. In addition, we recorded the distances between the anatomic obstacles and lateral epicondyle. RESULTS: The average humeral length was 271.8 mm. We identified anterior insertion of the deltoid muscle and the proximal part of the brachialis muscle as the main anatomic obstacles on the anterior surface of the humerus. The average distances between the lateral epicondyle and the most proximal and distal insertion of anterior deltoid were 188.9 mm and 138.7 mm, respectively. The average distance between the lateral epicondyle and the brachialis origin was 147.4 mm. Proportions of the distances between the lateral epicondyle and proximal of anterior deltoid insertion, the lateral epicondyle and distal of anterior deltoid insertion and the lateral epicondyle and proximal of brachialis origin to humeral length were 69.4%, 51%, and 54.2%, respectively. There was a high interobserver reliability (p<0.001). CONCLUSION: The deltoid insertion and proximal attachment of the brachialis muscles were identified as mechanical obstacles when performing the percutaneous plating. These sites caused difficulties with the procedure during the retrograde plate advancement through submuscular tunnel on the anterior surface of humerus. It was also noted that for successful plate advancement, it was necessary to release the anterior part of the deltoid insertion.