Controversies in orthopaedic oncology.

Chondrosarcoma is the second most common surgically treated primary bone sarcoma. Despite a large number of scientific papers in the literature, there is still significant controversy about diagnostics, treatment of the primary tumour, subtypes, and complications. Therefore, consensus on its day-to-day treatment decisions is needed. In January 2024, the Birmingham Orthopaedic Oncology Meeting (BOOM) attempted to gain global consensus from 300 delegates from over 50 countries. The meeting focused on these critical areas and aimed to generate consensus statements based on evidence amalgamation and expert opinion from diverse geographical regions. In parallel, periprosthetic joint infection (PJI) in oncological reconstructions poses unique challenges due to factors such as adjuvant treatments, large exposures, and the complexity of surgery. The meeting debated two-stage revisions, antibiotic prophylaxis, managing acute PJI in patients undergoing chemotherapy, and defining the best strategies for wound management and allograft reconstruction. The objectives of the meeting extended beyond resolving immediate controversies. It sought to foster global collaboration among specialists attending the meeting, and to encourage future research projects to address unsolved dilemmas. By highlighting areas of disagreement and promoting collaborative research endeavours, this initiative aims to enhance treatment standards and potentially improve outcomes for patients globally. This paper sets out some of the controversies and questions that were debated in the meeting.

Larger stem to bone diameter ratio predicts lower cemented endoprosthesis failure.

BACKGROUND AND OBJECTIVES: With continued advances in treatment options, patients with endoprosthetic reconstruction are living longer and consequently relying upon their devices for a longer duration. Major causes of endoprosthesis failure include aseptic loosening and mechanical failure. In the setting of tumor resection, loss of bone stock and use of radiation therapy increase the risk for these complications. As such, considerations of remaining native bone and stem length and diameter may be increasingly important. We asked the following questions: (1) What was the overall rate of endoprosthesis failure at a minimum of 5-year follow-up? (2) Does resection length increase implant failure rates? (3) Does implant size and its ratio to cortical width of bone alter implant failure rates? METHODS: We retrospectively analyzed patient outcomes at a single institution between the years of 1999-2022 who underwent cemented endoprosthetic reconstruction at the hip or knee and identified 150 patients. Of these 150, 55 had a follow-up of greater than 5 years and were used for analysis. Radiographs of these patients at time of surgery were assessed and measured for resection length, bone diameter, stem diameter, and remaining bone length. Resection percentage, and stem to bone diameter ratios were then calculated and their relationship to endoprosthesis failure were analyzed. RESULTS: Patients in this cohort had a mean age of 55.8, and mean follow-up of 59.96 months. There were 78 distal femoral replacements (52%), 16 proximal femoral replacements (10.7%), and 56 proximal tibial replacements (37.3%). There were five patients who experienced aseptic loosening and six patients who experienced mechanical failure. Patients with implant failure had a smaller mean stem to bone diameter (36% vs. 44%; p = 0.002). A stem to bone diameter of 40% appeared to be a breaking point between success and failure in this series, with 90% of patients with implant failure having a stem: bone ratio less than 40%. Stem to bone ratio less than 40% increased risk for failure versus stems that were at least 40% the diameter of bone (6/19 [31.6%] vs. 0/36 [0%]; odds ratio 0.68; p < 0.001). Resection length did not appear to have an impact on the rates of aseptic loosening and mechanical failure in this series. CONCLUSIONS: Data from this series suggests a benefit to using stems with a larger diameter when implanting cemented endoprostheses at the hip or knee. Stems which were less than 40% the diameter of bone were substantially more likely to undergo implant failure.

Effect of Vancomycin Applied to the Surgical Site on Fracture Healing in a Diabetic Rat Model.

BACKGROUND: Prophylactic vancomycin treatment decreases the prevalence of surgical site and deep infections by >70% in diabetic patients undergoing reconstructive foot and ankle surgery. Thus, determining whether clinically relevant local vancomycin doses affect diabetic fracture healing is of medical interest. We hypothesized that application of vancomycin powder to the fracture site during surgery would not affect healing outcomes, but continuous exposure of vancomycin would inhibit differentiation of osteoblast precursor cells and their osteogenic activity in vitro. METHODS: The vancomycin dose used to treat the diabetic rats was a modest increase to routine surgical site vancomycin application of 1 to 2 g for a 70-kg adult (21 mg/kg). After femur fracture in BB-Wistar type 1 diabetic rats, powdered vancomycin (25 mg/kg) was administered to the fracture site. Bone marrow and periosteal cells isolated from diabetic bones were cultured and treated with increasing levels of vancomycin (0, 5, 50, 500, or 5000 µg/mL). RESULTS: Radiographic scoring, micro-computed tomography (µCT) analysis, and torsion mechanical testing failed to identify any statistical difference between the vancomycin-treated and the untreated fractured femurs 6 weeks postfracture. Low to moderate levels of vancomycin treatment (5 and 50 µg/mL) did not impair cell viability, osteoblast differentiation, or calcium deposition in either the periosteum or bone marrow-derived cell cultures. In contrast, high doses of vancomycin (5000 µg/mL) did impair viability, differentiation, and calcium deposition. CLINICAL RELEVANCE: In this diabetic rodent fracture model, vancomycin powder application at clinically relevant doses did not affect fracture healing or osteogenesis.

Local zinc treatment enhances fracture callus properties in diabetic rats.

The effects of locally applied zinc chloride (ZnCl2 ) on early and late-stage parameters of fracture healing were evaluated in a diabetic rat model. Type 1 Diabetes has been shown to negatively impact mechanical parameters of bone as well as biologic markers associated with bone healing. Zinc treatments have been shown to reverse those outcomes in tests of nondiabetic and diabetic animals. This study is the first to assess the efficacy of a noncarrier mediated ZnCl2 on bony healing in diabetic animals. This is a promising basic science approach which may lead to benefits for diabetic patients in the future. Treatment and healing were assessed through quantification of callus zinc, radiographic scoring, microcomputed tomography (µCT), histomorphometry, and mechanical testing. Local ZnCl2 treatment increased callus zinc levels at 1 and 3 days after fracture (p ≤ 0.025). Femur fractures treated with ZnCl2 showed increased mechanical properties after 4 and 6 weeks of healing. Histomorphometry of the ZnCl2 -treated fractures found increased callus cartilage area at Day 7 (p = 0.033) and increased callus bone area at Day 10 (p = 0.038). In contrast, callus cartilage area was decreased (p < 0.01) after 14 days in the ZnCl2 -treated rats. µCT analysis showed increased bone volume in the fracture callus of ZnCl2 -treated rats at 6 weeks (p = 0.0012) with an associated increase in the proportion of µCT voxel axial projections (Z-rays) spanning the fracture site. The results suggest that local ZnCl2 administration improves callus chondrogenesis leading to greater callus bone formation and improved fracture healing in diabetic rats.

Infectious disease specialists and teamwork strategies worldwide: the World Association against Infection in Orthopedics and Trauma (WAIOT) and SICOT continue to cooperate in fighting musculoskeletal infections.

Bone and joint infections are associated with a devastating global burden. The successful treatment of these infections requires a multidisciplinary approach between orthopedic surgeons and experts of different disciplines. This multidisciplinary approach has gained ground over the past decades in modern infection units as a more effective treatment strategy, yielding better outcomes regarding infection eradication rates, length of hospital stay, and overall cost of treatments. Additionally, preventing and managing musculoskeletal infections requires strong connections between medical associations, biological laboratories, and the pharmaceutical industry worldwide. In this context, SICOT and World Association against Infection in Orthopaedics and Trauma (WAIOT) relationships have been increasing. The present editorial article discusses the multidisciplinary approach for managing bone and joint infections worldwide, explores the controversies in practices in terms of training, area of expertise, and extent of clinical involvement, and emphasizes the role of societies in research, prevention and management of musculoskeletal infections. The purpose is to acknowledge what orthopedics can obtain from specialists dealing with bone and joint infections and to consolidate their practice to provide the best care for orthopedic patients.

Diagnosis and Treatment of Lumbar Giant Cell Tumor of the Spine: Update on Current Management Strategies.

(1) Background: Giant Cell Tumor of the spine remains a difficult tumor to treat. Recent advances in adjuvant therapy such as denosumab and innovations in surgical technique in the last 5 years have given providers new options for treatment after a successful diagnosis of the tumor. (2) Methods: Articles published between 1927 and 2021 were selected from PubMed and Scopus searches using key words "Giant Cell Tumor" AND "Lumbar Spine" AND "Treatment". Relevant articles were reviewed and selected by the authors. (3) Results: A total of 191 articles were discovered. Complete en bloc spondylectomy remains the most definitive treatment option; however, this surgery is challenging and carries a high rate of complication. New adjuvant therapies including denosumab offer a viable alternative to surgery. (4) En bloc spondylectomy remains the gold standard treatment for Giant Cell Tumor of the spine with the lowest published recurrence rate. The use of (neo)adjuvant denosumab improves recurrence rates. More data are needed to determine if denosumab alone is a viable standalone definitive treatment.

Evolution of Surgical Management of Metastatic Disease of the Pelvis.

The surgical management of acetabular and pelvic lesions due to metastatic bone disease is complex in nature. These patients are typically in a frail state, having severe pain, limited mobility, and impaired wound healing. This causes a potential for complications, a high concern for the surgeon. Compounding these issues is limited life span for these patients given the advancement of the disease. Considerations for patients undergoing surgical treatment are achievement of significant pain relief and restoration of ambulation, all while having minimal complications during the postoperative period. Management may also include nonsurgical and interventional methods. A multidisciplinary approach is required for the successful treatment of these patients. Although there have been various surgical methods described, there is still no standardized modality that has been noted. These lesions often require complex decision making, imaging, and surgical reconstruction.

Cemented-augmented fixation of metastatic humeral lesions without segmental bone loss results in reliable outcomes.

Background: Treatment of metastatic lesions to the humerus is dependent on patient's pain, lesion size and location, and post-operative functional goals. Surgical options include plate or nail fixation [open reduction internal fixation (ORIF)], or endoprosthetic replacement (EPR), with cement augmentation. The objective of this study was to perform a single institution retrospective analysis of outcomes by method of reconstruction, tumor volume, and pathologic diagnosis. Methods: The records of 229 consecutive patients treated surgically for appendicular metastatic disease from 2005-2018 at our musculoskeletal oncology center were retrospectively reviewed following institutional review board (IRB) approval. Indications for surgical treatment at the humerus included patients who presented with impending and displaced pathologic fractures. Results: Sixty patients (34 male, 26 female) with a mean age of 62.9±12.2 were identified who were treated surgically at the proximal (n=21), diaphyseal (n=29), or distal (n=10) humerus. Forty-nine (82%) patients presented with displaced pathologic fractures. The remaining eleven patients had a mean Mirels score of 9.5. There was no difference in overall complication rate between EPR or ORIF [4/36 (11%) versus 2/24 (8%); P=0.725]. Mean Musculoskeletal Tumor Society (MSTS) scores were 83% for both EPR and ORIF, with no differences in subgroup analyses at the proximal, diaphyseal, or distal humerus. Patients with cortical destruction on anterior posterior (AP) and lateral imaging were at increased risk for mechanical failure [2/6 (33%) versus 0/18 (0%), P=0.015]. Conclusions: In conclusion, when pathologic pattern permits, cement-augmented fixation allows for stabilization of pathologic bone, while minimizing risk of soft-tissue detachment, while EPR resulted in similar outcomes in patients with more extensive bone destruction. Increased tumor volume was associated with lower MSTS scores.

IVC filter placement in patients undergoing surgical treatment of bone or soft-tissue tumors.

BACKGROUND AND OBJECTIVES: Patients with cancer to bone or soft tissues undergoing orthopedic procedures may be unable to receive pharmacologic prophylaxis for venous thromboembolism (VTE). Inferior vena cava (IVC) filters may be an effective method to prevent fatal pulmonary embolism (PE) in these patients. METHODS: Retrospective chart review performed for patients surgically treated for malignant disease of bone or soft tissue who had IVC filter placement. Type of surgery, anatomic region, and development of wound complications requiring repeat surgery were analyzed. RESULTS: From 2007 to 2018, 286 patients received IVC filters. Ten (3.5%) patients suffered deep vein thrombus (DVT) postoperatively. There was no acute fatal PE. Two patients suffered PE at 2 and 99 days postoperatively. Risk of DVT was comparable following surgery with endoprosthesis versus open reduction and internal fixation (p = 0.056) and with soft tissue versus bone involvement (p = 0.620). Three filter-related complications occurred. Patients disease at the femur had the highest rate of DVT. CONCLUSIONS: Following treatment of malignant disease of bone or soft-tissues, two patients with IVC filter placement experienced nonfatal PE and three patients experienced filter-related complications. No patients in this series experienced a fatal PE.

Improved osteogenesis in rat femur segmental defects treated with human allograft and zinc adjuvants.

Bone allograft is widely used to treat large bone defects or complex fractures. However, processing methods can significantly compromise allograft osteogenic activity. Adjuvants that can restore the osteogenic activity of processed allograft should improve clinical outcomes. In this study, zinc was tested as an adjuvant to increase the osteogenic activity of human allograft in a Rag2 null rat femoral defect model. Femoral defects were treated with human demineralized bone matrix (DBM) mixed with carboxy methyl cellulose containing ZnCl2 (0, 75, 150, 300 µg) or Zn stearate (347 µg). Rat femur defects treated with DBM-ZnCl2 (75 µg) and DBM-Zn stearate (347 µg) showed increased calcified tissue in the defect site compared to DBM alone. Radiograph scoring and µCT (microcomputed tomography) analysis showed an increased amount of bone formation at the defects treated with DBM-Zn stearate. Use of zinc as an adjuvant was also tested using human cancellous bone chips. The bone chips were soaked in ZnCl2 solutions before being added to defect sites. Zn adsorbed onto the chips in a time- and concentration-dependent manner. Rat femur defects treated with Zn-bound bone chips had more new bone in the defects based on µCT and histomorphometric analyses. The results indicate that zinc supplementation of human bone allograft improves allograft osteogenic activity in the rat femur defect model.

Does the Use of Intraoperative Angiography Reduce the Incidence of Postoperative Wound and Flap Complications in Complex Lower Extremity Oncologic Reconstruction?

INTRODUCTION: Intraoperative laser angiography via indocyanine green (ICG) has become a valuable tool in objectively assessing tissue perfusion in reconstructive procedures. Studies have demonstrated the utility of ICG angiography (ICGA) for decreasing both mastectomy skin flap necrosis and wound healing complications in abdominal wall reconstruction. This tool has not been studied in lower extremity oncologic reconstruction. The objective of this study was to compare postoperative complications in lower extremity oncologic reconstruction managed with or without laser-assisted ICGA. METHODS: A retrospective chart review was performed of patients undergoing complex lower extremity oncologic reconstruction at a single institution between 2000 and 2018. Patient information regarding demographics, comorbidities, operative procedures, and postoperative complications was analyzed. RESULTS: Sixty-one patients were identified in our study. As some patients underwent multiple reconstructive surgeries, a total of 76 reconstructive procedures were analyzed. Patients with plastic surgery reconstruction using ICGA (n = 36) were compared with those without, non-ICGA (n = 40). No significant differences in age, sex, smoking status, chemotherapy, or radiation history were identified between cohorts. The total number of postoperative complications did not statistically differ between cohorts. There was no statistically significant difference in the number of required reoperation because of a postoperative complication between the ICGA and non-ICGA groups (0.44 vs 0.4). CONCLUSIONS: The incidence of postoperative wound complications after complex lower extremity oncologic reconstruction remains high. The findings of our study suggest that clinical judgment of flap and soft tissue viability, as compared with ICGA, may lead to comparable operative outcomes and be more cost-effective. Long-term follow-up and prospective studies are needed to further investigate this trend.

Local insulin application has a dose-dependent effect on lumbar fusion in a rabbit model.

The purpose of this study was to determine if locally applied insulin has a dose-responsive effect on posterolateral lumbar fusion. Adult male New Zealand White rabbits underwent posterolateral intertransverse spinal fusions (PLFs) at L5-L6 using suboptimal amounts of autograft. Fusion sites were treated with collagen sponge soaked in saline (control, n = 11), or with insulin at low (5 or 10 units, n = 13), mid (20 units, n = 11), and high (40 units, n = 11) doses. Rabbits were euthanized at 6 weeks. The L5-L6 spine segment underwent manual palpation and radiographic evaluation performed by two fellowship trained spine surgeons blinded to treatment. Differences between groups were evaluated by analysis of variance on ranks followed by post-hoc Dunn's tests. Forty-three rabbits were euthanized at the planned 6 weeks endpoint, while three died or were euthanized prior to the endpoint. Radiographic evaluation found bilateral solid fusion in 10%, 31%, 60%, and 60% of the rabbits from the control and low, mid, and high-dose insulin-treated groups, respectively (p < 0.05). As per manual palpation, 7 of 10 rabbits in the mid-dose insulin group were fused as compared to 1 of 10 rabbits in the control group (p < 0.05). This study demonstrates that insulin enhanced the effectiveness of autograft to increase fusion success in the rabbit PLF model. The study indicates that insulin or insulin-mimetic compounds can be used to promote bone regeneration.

Management of Large Segmental Bone Defects at the Knee With Intramedullary Stabilized Antibiotic Spacers During Two-Stage Treatment of Endoprosthetic Joint Infection.

BACKGROUND: Following debridement of infected prostheses that require reconstruction with an endoprosthetic replacement (EPR), instability related to segmental residual bone defects present a challenge in management with 2-stage reimplantation. METHODS: We retrospectively reviewed all patients treated for revision total joint or endoprosthetic infection at the knee from 1998 to 2018. At our institution, patients with skeletal defects >6 cm following explant of prosthesis and debridement (stage 1) were managed with intramedullary nail-stabilized antibiotic spacers. Following stage 1, antimicrobial therapy included 6 weeks of intravenous antibiotics and a minimum of 6 weeks of oral antibiotics. Following resolution of inflammatory markers and negative tissue cultures, reimplantation (stage 2) of an EPR was performed. RESULTS: Twenty-one patients at a mean age of 54 ± 21 years were treated for prosthetic joint infection at the knee. Polymicrobial growth was detected in 38% of cases, followed by coagulase-negative staphylococci (24%) and Staphylococcus aureus (19%). Mean residual skeletal defect after stage 1 treatment was 20 cm. Prosthetic joint infection eradication was achieved in 18 (86%) patients, with a mean Musculoskeletal Tumor Society score of 77% and mean knee range of motion of 100°. Patients with polymicrobial infections had a greater number of surgeries prior to infection (P = .024), and were more likely to require additional debridement prior to EPR (odds ratio 12.0, P = .048). CONCLUSION: Management of large segmental skeletal defects at the knee following explant using intramedullary stabilized antibiotic spacers maintain stability and result in high rates of limb salvage with conversion to an endoprosthesis.

Risk factors of venous thromboembolism in patients with benign and malignant musculoskeletal tumors: a dual database analysis.

PURPOSE: Venous thromboembolism (VTE) is a potentially life-threatening condition associated with both orthopaedic surgery and tumour growth. In this study, we identify risk factors associated with VTE in patients with musculoskeletal tumours using two national datasets. METHODS: The ACS-NSQIP and NIS databases were queried for patients undergoing surgery with a diagnosis of benign or malignant musculoskeletal tumours. Chi-square and binary logistic regression analyses were used to determine risk factors for VTE. RESULTS: The incidence of VTE was 2% in both databases. Patients with malignant tumours, those with tumours of the pelvis, sacrum, or coccyx, obesity, arrhythmias, paralysis, metastatic disease, coagulopathy, and recent weight loss were at increased risk for VTE. In patients with benign tumours, those who were African American, those with tumours of the pelvis, sacrum, or coccyx, diabetes, anaemia, and coagulopathy were at increased risk of VTE. CONCLUSIONS: Patients with malignant or benign lesion are at greater risk of VTE if they are age 30 and over, of the African American population, or with tumors of the pelvis/sacrum/coccyx, or any of the following comorbidities: pulmonary disease, paralysis, other neurological disorders, or coagulopathy.

Outcomes following periacetabular tumor resection: A 25-year institutional experience.

BACKGROUNDS AND OBJECTIVES: Following tumor resection involving the acetabulum (periacetabular), various methods of reconstruction exist. The objective of this study was to analyze functional outcomes and complication rates by extent of periacetabular tumor resection, as well as by method of reconstruction. METHODS: Twenty-three patients underwent periacetabular resection for a primary pelvic bone tumor from 1993-2018 at a single institution. Complications were documented and functional outcomes were assessed using the Musculoskeletal Tumor Society (MSTS) scoring system. RESULTS: Mean age was 42.8 ± 22.6 years. Mean follow-up was 107 ± 75 months. MSTS scores were highest in patients with allograft reconstruction (80.2%) and lowest in saddle reconstruction (38.0%). MSTS scores were higher in patients with Type II periacetabular resection alone compared with Type II + additional resection (78.6% vs 60.3%; P = .019). Complications were lower in patients with Type II periacetabular resection alone (75% vs 28.6%; P = .036). Complications were highest following allograft reconstruction (78%) and lowest following hemipelvectomy without reconstruction (20%). CONCLUSION: Patients who underwent allograft/APC or nonsaddle metallic reconstruction experienced the highest functional outcome scores, but also sustained a higher complication rate than patients with hemipelvectomy without reconstruction. Patients with resection of ilium and/or pubis in addition to the periacetabular region had lower functional outcome scores and higher risk for complication.

Reconstruction with Custom Unicondylar Hemiarthroplasty following Tumor Resection: A Case Series and Review of the Literature.

For patients with tumors of the distal femur, options for limb salvage include tumor resection followed by reconstruction. While reconstruction commonly involves a distal femoral replacement, careful selection of patients with tumor involvement limited to a single condyle may be candidates for reconstruction with distal femur hemiarthroplasty. In these procedures, resection spares considerably more native anatomy. Three consecutive patients who underwent resection and reconstruction at the distal femur with custom unicondylar hemiarthroplasty are presented in this case series at a mean follow-up of 45 months (range, 26-78). In two cases, prostheses were utilized as a secondary procedure after failure of initial reconstruction. In one case, the custom prosthesis was utilized as the primary method of reconstruction. Mean Musculoskeletal Tumor Society disease-specific scores were 26.7 (range, 25-28). All patients achieved a return to full weight bearing, activities of daily living, and functional range of motion. In appropriately selected patients with tumors of the distal femur, reconstruction with custom unicondylar hemiarthroplasty provides benefits including optimal function postoperatively via preservation of tumor-free bone and ligamentous structures. Additionally, maintenance of greater bone stock may confer benefits to patients with pathology at a high likelihood for recurrence and need for subsequent procedures.

Complications following allograft reconstruction for primary bone tumors: Considerations for management.

INTRODUCTION: The aim of this study was to investigate complication rates and types following allograft reconstruction and discuss unique considerations for management. METHODS: Seventy-four consecutive patients underwent large segment allograft reconstruction following resection of primary musculoskeletal tumors from 1991 to 2016. Mean patient age was 32 ±â€¯20 years (range, 5-71 years). Minimum follow-up was 2 years unless patients were lost to disease prior. Mean follow-up was 105 months. RESULTS: Thirty-five patients had complications requiring subsequent surgery at a mean of 30 months (range, 1-146 months) post-operatively. Individual complication rates were 29%, 50%, and 42% for Allograft Prosthetic Composite, Intercalary, and Osteoarticular allograft reconstruction, respectively. Risk factors for complication included age less than 30 (OR 4.5; p = 0.002), male gender (OR 2.8; p = 0.031), chemotherapy (OR 4.4; p = 0.003), lower extremity disease (OR 3.4; p = 0.025). In patients with complications, limb-retention rate was 91% and mean MSTS scores were 23.6. CONCLUSION: Despite considerable complication rates, management with a systematic approach results in successful outcomes with limb-retention greater than 90% and mean MSTS scores of 79%. In carefully selected patients, allografts provide a reliable method of reconstruction with treatable complications occurring at a mean of 30 months.

Sterile particle-induced inflammation is mediated by macrophages releasing IL-33 through a Bruton's tyrosine kinase-dependent pathway.

Initiation of the innate sterile inflammatory response that can develop in response to microparticle exposure is little understood. Here, we report that a potent type 2 immune response associated with the accumulation of neutrophils, eosinophils and alternatively activated (M2) macrophages was observed in response to sterile microparticles similar in size to wear debris associated with prosthetic implants. Although elevations in interleukin-33 (IL-33) and type 2 cytokines occurred independently of caspase-1 inflammasome signalling, the response was dependent on Bruton's tyrosine kinase (BTK). IL-33 was produced by macrophages and BTK-dependent expression of IL-33 by macrophages was sufficient to initiate the type 2 response. Analysis of inflammation in patient periprosthetic tissue also revealed type 2 responses under aseptic conditions in patients undergoing revision surgery. These findings indicate that microparticle-induced sterile inflammation is initiated by macrophages activated to produce IL-33. They further suggest that both BTK and IL-33 may provide therapeutic targets for wear debris-induced periprosthetic inflammation.

Surgical Reconstruction of the Acetabulum and Pelvis in Metastatic Bone Disease.

Management of a painful metastatic acetabular lesion is complex and requires the assessment of tumor size and location, remaining integrity of the acetabulum, analgesic requirements, ability to use postoperative radiation, and projected patient survival. Patients presenting with suspected periacetabular metastasis frequently have groin pain aggravated by weight bearing. After a complete physical examination, advanced imaging and a complete laboratory workup should be performed to assess the extent of local and systemic disease. If a patient has a previously identified metastatic lesion, it is beneficial to communicate with the patient's medical oncologist to gather information on responses to chemotherapeutic agents, hormonal agents, and radiation therapy. Management may be nonsurgical, interventional, or surgical. Despite the limited life expectancy of patients with periacetabular metastasis, when performed in the appropriate setting, reconstruction by using anti-protrusio cages, screws, and cemented hip arthroplasty can improve quality of life by aiding independent ambulation and decreasing pain.

Dealing with the loss of a resident: An analysis of burnout rates in a reduced complement training program.

BACKGROUND: Residents in all fields of medicine experience high levels of burnout and less job-related satisfaction due to the stress experienced during training. Reduced complement residency classes often experience increased workloads due to the need to compensate for the fewer number of classmates. OBJECTIVE: The goal of this study was to examine whether residency classes of reduced size experience higher levels of burnout. METHODS: The Maslach Burnout Inventory Survey was distributed to all orthopaedic residents at our institution for four consecutive years. Emotional exhaustion≥27 and depersonalization≥10 correlate with high levels of burnout. At our institution, two residents were lost during their second year of training. Group 1 (n = 56) consisted of residents with reduced-size classes, while group 2 (n = 60) consisted of residents with full complement classes. RESULTS: Mean emotional exhaustion (29 vs. 30) and depersonalization (17 vs. 17) scores were comparable between reduced and full complement classes. The Maslach data from our study showed no statistical difference in burnout levels between classes of full complement and reduced complement. CONCLUSIONS: When compared to a previous study on burnout conducted in large orthopaedic residency programs, our entire residency program did demonstrate similar levels of emotional exhaustion and depersonalization.