Primary osseous leiomyosarcoma of humerus misinterpreted as aneurysmal bone cyst: A case report and literature review.

RATIONALE: Primary leiomyosarcoma of the bone (LMSB) is a rare aggressive sarcoma with limited treatment options. Histopathologic and immunohistochemical features are similar to their more common uterine and soft tissue counterparts. However, its broader spectrum of histopathologic features and rarity make diagnostic challenges. PATIENT CONCERNS: We present a case of LMSB in a 20-year-old female who presented with left shoulder aching pain for 3 months. An osteolytic intramedullary lesion was found in the left proximal humeral epi-metaphysis. DIAGNOSES: Initial open biopsy showed a giant cell tumor of bone with aneurysmal bone cyst (ABC)-like changes. However, an open biopsy followed by extended curettage showed LMSB with ABC-like changes. INTERVENTIONS: Wide excision of the lesion and bipolar hemiarthroplasty followed by concomitant chemoradiation therapy was conducted. The mass was completely removed without significant problems. OUTCOMES: Complete mass excision and symptomatic improvements were achieved, and no subsequent relapses were observed. LESSONS: The authors encountered a rare case of LMSB. Most occurrences are in the lower extremity and trunk, respectively. ABC-like changes in bone tumors can lead to misdiagnosis. In this case, the ABC-like changes developed from the underlying LMSB as a secondary alteration. A careful examination of the underlying bone tumor is crucial to avoid misdiagnosing it as ABC or exhibiting ABC-like changes. Moreover, there has been no case report of LMSB with secondary ABC-like changes in bone.

Comparison of reconstructive techniques for nonprimary malignancies in the proximal humerus.

BACKGROUND: Endoprostheses (EPC) are often utilized for reconstruction of the proximal humerus with either hemiarthroplasty (HA) or reverse arthroplasty (RA) constructs. RA constructs have improved outcomes in patients with primary lesions, but no studies have compared techniques in metastatic disease. The aim of this study is to compare functional outcomes and complications between HA and RA constructs in patients undergoing endoprosthetic reconstruction for proximal humerus metastases. METHODS: We retrospectively reviewed our institutional arthroplasty database to identify 66 (56% male; 38 HA and 28 RA) patients with a proximal humerus reconstruction for a non-primary malignancy. The majority (88%) presented with pathologic fracture, and the most common diagnosis was renal cell carcinoma (48%). RESULTSS: Patients with RA reconstructions had better postoperative forward elevation (74° vs. 32°, p < 0.01) and higher functional outcome scores. HA patients had more complications (odds ratio 13, p < 0.01), with instability being the most common complication. CONCLUSIONS: Patients with nonprimary malignancies of the proximal humerus had improved functional outcomes and fewer complications after undergoing reconstruction with a reverse EPC compared to a HA EPC. Preference for reverse EPC should be given in patients with good prognosis and ability to complete postoperative rehabilitation.

Efficacy of denosumab treatment for lung metastasis secondary to proximal humerus chondroblastoma.

Chondroblastoma is a rare benign cartilaginous tumor that accounts for approximately 1% of bone tumors, but it can be associated with lung metastasis in extremely rare cases, leading to a poor prognosis and death. Herein, we report the case of a 19-year-old male patient who presented with an aggressive chondroblastoma of the proximal humerus and bilateral lung metastasis. The patient was treated with wide local resection, partial metastasectomy, and denosumab. Denosumab treatment was effective in controlling metastatic progression and preventing local recurrence.

Does the ulnohumeral angle have a role in the aetiopathogenesis of lateral epicondylitis?

The pathophysiology of lateral epicondylitis (LE) remains not fully elucidated, as it involves a complex interaction of anatomical structures. The primary objective of the research is to identify a potential relationship between LE and the ulnohumeral angle (UHA), which demonstrates the coronal alignment of the elbow. Patients diagnosed with LE between September 1st, 2020, and September 1st, 2023, were retrospectively examined. Demographic information and UHA measurements of patients meeting the inclusion criteria and a control group with similar criteria were collected. Measurements were independently conducted by 2 orthopedists at a 2-week interval and compared. Among 413 patients meeting the inclusion criteria and the control group comprising 420 patients, there were no significant differences in age, gender, and side (P = .447, P = .288, P = .159, respectively). The mean UHA for the LE group was 13.49 ±â€…4.24, while for the control group, it was 12.82 ±â€…9.19, showing a significant difference (P = .026). The inter-observer and intraobserver reliability of the angle measurements were both above 0.80. We hypothesize that the increase in UHA in patients with LE reflects an adaptive change secondary to compressive forces acting on the lateral aspect of the elbow. This study is the first to describe the relationship between LE and UHA based on anatomical-biomechanical foundations, suggesting a cause-and-effect relationship. Further studies are warranted to delve deeper into this relationship.

Severe Hemodynamic Collapse During Humerus Stabilization with Photodynamic Implant: A Report of Two Cases.

CASE: We present 2 cases of severe hemodynamic collapse during prophylactic stabilization of impending pathologic humerus fractures using a photodynamic bone stabilization device. Both events occurred when the monomer was infused under pressure into a balloon catheter. CONCLUSION: We suspect that an increase in intramedullary pressure during balloon expansion may cause adverse systemic effects similar to fat embolism or bone cement implantation syndrome. Appropriate communication with the anesthesia team, invasive hemodynamic monitoring, and prophylactic vent hole creation may help mitigate or manage these adverse systemic effects.

Adolescent idiopathic scoliosis: is there a relationship between Risser staging and the proximal humerus ossification system?

PURPOSE: To evaluate whether there is a mismatch between Risser staging and the proximal humerus ossification system (PHOS); and to analyze the correlation in the skeletal maturity stages between the two humeral epiphyses. METHODS: Data from patients aged 10 to 18 years with adolescent idiopathic scoliosis (AIS) seen between 2018 to 2021 were analyzed. In an anteroposterior (AP) spine radiograph the ossification process was evaluated using the Risser classification method and bilateral PHOS (if both humeral epiphyses were visualized). A mismatch between methods was defined as a Risser 0-1 (relatively skeletally immature) with a PHOS 4-5 (skeletally mature), or a Risser 2-5 (relatively skeletally mature) with a PHOS 1-3 (skeletally immature). The McNemar test was used to calculate the significance of the mismatch. RESULTS: A mismatch between Risser and PHOS stages was observed in 28.5% of 105 patients, which was statistically significant (p < 0.001). Of the 49 patients with a Risser 0-1, 55.1% (n = 27) had a PHOS 4-5. None of the patients with a Risser 2-5 had a PHOS 1-3. In the 47 patients in whom both humeri were visualized, the absolute correlation between the left and right PHOS values was 95.7%. CONCLUSION: Of AIS patients who are relatively skeletally immature according to Risser staging, more than half may be skeletally mature when measured with PHOS. In patients with a Risser 0-1, it is recommended to measure skeletal maturity in an AP spine radiograph using the PHOS method, which may more accurately guide treatment decision-making, without the need to visualize both humeral epiphyses in this radiographic projection. LEVEL OF EVIDENCE: IV.

An Unusual Case of Clear Cell Chondrosarcoma With Early Metastatic Recurrence.

We present a case of a 58-year-old male who presented following 4 months of progressively worsening right upper extremity pain. Initial pathology demonstrated pleomorphic chondroblasts with increased mitotic activity indicating an intermediate grade (Grade 2) clear cell chondrosarcoma of the proximal humerus. Following surgical resection, the primary lesion demonstrated aggressive behavior and early metastasis to the cervical and thoracic spine. The patient unfortunately expired 30 months after initial presentation. Although clear cell chondrosarcoma has been historically regarded as low grade, we present a unique example of an aggressive clinical course of clear cell chondrosarcoma.

18 F-FDG PET/CT Imaging of Isolated Myeloid Sarcoma in the Right Humerus.

ABSTRACT: Myeloid sarcoma is a neoplastic mass formed by the infiltration of primitive or immature myeloid cells into organs and tissues outside the bone marrow. It may occur before, at the same time, or manifest as the recurrence of acute myeloid leukemia, myelodysplastic syndromes, and chronic myeloproliferative syndromes. It may involve any organ or tissue, including skin, soft tissue, lymph nodes, and gastrointestinal tract and bone. Isolated humerus involvement is extremely rare. Herein, we present the FDG PET/CT findings of a rare case of isolate myeloid sarcoma in the right humerus, which showed only increased bone density with moderate FDG uptake.

Rare presentation of a primary intraosseous glomus tumor in the humerus of a teenager.

A glomus tumor is a benign mesenchymal tumor comprised of cells that resemble the perivascular modified smooth muscle cells of the glomus body. Glomus tumors typically appear in the superficial lesions of the soft tissue in the extremities, such as the subungual region. However, their occurrence in the bone is rare, with only about 30 cases reported to date. Half of these cases involved the distal phalanges of the fingers or toes, with only three reported cases involving the long bones. Here, we present the first case, a primary glomus tumor in the humerus of a 14-year-old female. An osteolytic and cystic lesion was detected after a pathological fracture occurred during exercise. Despite the tumor's large size, no pathological findings indicated malignancy. The fracture healed through conservative treatment, while the tumor was effectively managed with curettage. Appropriate medical care can be provided to patients by focusing on pathological findings.

Does A Single Osteotomy Technique for Frozen Autograft (Pedicled Freezing) in Patients With Malignant Bone Tumors of the Long Bones Achieve Union and Local Tumor Control?

BACKGROUND: Biological reconstruction by replanting the resected tumor-bearing segment is preferred by some surgeons when caring for a patient with a bone sarcoma. Frozen autografts are advantageous because they are cost-effective, provide an excellent fit, permit the maintenance of osteoinductive and osteoconductive properties, and are not associated with transmission of viral disease. The pedicle frozen autograft technique, in which only one osteotomy is made for the freezing procedure, keeping the affected segment in continuity with the host bone and soft tissue instead of two osteotomies, maintains the affected segment with the host bone and soft tissue. This could restore blood flow more rapidly in a frozen autograft than in a free-frozen autograft with two osteotomies. QUESTIONS/PURPOSES: (1) In what proportion of patients was union achieved by 6 months using this technique of frozen autografting? (2) What complications were observed in a small series using this approach? (3) What was the function of these patients as determined by Musculoskeletal Tumor Society (MSTS) score? (4) What proportion of patients experienced local recurrence? METHODS: Between 2014 and 2017, we treated 87 patients for primary sarcomas of the femur, tibia, or humerus. Of those, we considered patients who could undergo intercalary resection and showed a good response to neoadjuvant chemotherapy as potentially eligible for this technique. Based on these criteria, 49% (43 patients) were eligible; a further 9% (eight) were excluded because of inadequate bone quality (defined as cortical thickness less than 50% by CT assessment). We retrospectively studied 32 patients who were treated with a single metaphyseal osteotomy, the so-called pedicle freezing technique, which uses liquid nitrogen. There were 20 men and 12 women. The median age was 18 years (range 13 to 48 years). The median follow-up duration was 55 months (range 48 to 63 months). Patients were assessed clinically and radiologically regarding union (defined in this study as bony bridging of three of four cortices by 6 months), the proportion of patients experiencing local recurrence, the occurrence of nononcologic complications, and MSTS scores. RESULTS: Three percent (one of 32) of the patients had nonunion (no union by 9 months). The median MSTS score was 90%, with no evidence of metastases at the final follow-up interval. Nine percent (three of 32) of our patients died. The local recurrence rate was 3.1% (one of 32 patients). The mean restricted disease-free survival time at 60 months (5 years) was 58 months (95% CI 55 to 62 months). Twenty-five percent of patients (eight of 32) experienced nononcologic complications. This included superficial skin burns (two patients), superficial wound infection (two patients), deep venous thrombosis (one patient), transient nerve palsy (two patients), and permanent nerve palsy (one patient). CONCLUSION: This treatment was reasonably successful in patients with sarcomas of the femur, tibia, and humerus who could undergo an intercalary resection, and this treatment did not involve the epiphysis and upper metaphysis. It avoids a second osteotomy site as in prior reports of freezing techniques, and union was achieved in all but one patient. There were few complications or local recurrences, and the patients' function was shown to be good. This technique cannot be used in all long-bone sarcomas, but we believe this is a reasonable alternative treatment for patients who show a good response to neoadjuvant chemotherapy, those in whom intercalary resection is feasible while retaining at least 2 cm of the subchondral area, and in those who have adequate bone stock to withstand the freezing process. Experienced surgeons who are well trained on the recycling technique in specialized centers are crucial to perform the technique. Further study is necessary to see how this technique compares with other reconstruction options. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Durability of intercalary endoprosthesis for humeral reconstruction.

INTRODUCTION: The humerus is a common site of metastases and primary tumors. For some patients with a segmental defect and/or diaphyseal cortical destruction a cemented intercalary device may provide a more reliable construct, however data on their use is limited. METHODS: We reviewed 43 (28 male and 15 female) patients treated with an intercalary humeral spacer at a single tertiary referral center between 1989 and 2022. Humeral lesions were most commonly secondary to metastatic disease (n = 29, 68%), with 25 (58%) patients presenting with a pathologic fracture. Mean age and body mass index were 66 years and 27.9 kg/m2 . First generation taper joint device were used in 22 patients and second-generation lap device in 21 patients. RESULTS: Following reconstruction the 2-year overall survival was 30%. Mechanical complications occurred in 11 patients, most commonly aseptic loosening (n = 6, 14%). With death as a competing risk, the cumulative incidence of mechanical failure was 28% at 2-years postoperative. Following the procedure, mean Musculoskeletal Tumor Society scores was 70% and mean shoulder elevation was 87°. CONCLUSION: Reconstruction of the humeral diaphysis with an intercalary endoprosthesis provides restoration of function of the upper extremity, however, is associated with one in four patients having mechanical failure.

The comparison of functional bracing of humeral shaft fractures: thermoplastic custom against preprepared commercial braces.

BACKGROUND: Functional humeral bracing of midshaft humeral fractures has been widely accepted as a gold standard for nonoperative treatment. Despite reported high union rates, there is no proven superiority of any orthosis. Here we aim to compare the outcomes after the use of custom-made thermoplastic vs. commercial humeral brace with regard to time to union, nonunion rates, types of nonunion, and conversion to surgery. METHODS: Patients with humeral fractures treated between 2018 and 2021 were identified retrospectively by electronic records. Only diaphyseal humerus fractures (AO 12) were included in the study. Proximal (AO 11) or distal (AO 13) fractures, open fractures, pathologic fractures, bilateral fractures, multiple fractures, and patients lost to follow-up were excluded. Patients attending one center received a custom-made thermoplastic splint, whereas those at the other center had an off-the-shelf humeral brace applied. Radiologic union was defined as healing of at least 3 of 4 cortices determined from follow-up radiographs. Data calculations were performed using the χ2 test. RESULTS: A total of 53 patients treated with a thermoplastic brace and 43 with a commercial brace were identified. A total of 52 men were included, and the cohort's mean age was 60.1 years (standard deviation: 16.1 years). Both groups had similar gender and age distributions. More patients achieved union with a thermoplastic brace (79.2%) than those with a commercial brace (76.7%), which was statistically significant (χ2, P = .04). Although time to union was similar both clinically and radiologically, patients with a commercial brace converted to surgical treatment more frequently (11 vs. 14 cases). CONCLUSION: Thermoplastic custom-made braces provide better fracture stability, allowing for statistically significantly higher rates of fracture union during a similar treatment period to commercially available splints. Patients wearing a commercial splint were significantly more likely to develop hypertrophic nonunion requiring surgery.

Advances in Oncologic Shoulder Girdle Resection and Reconstruction.

The bony shoulder girdle consists of the clavicle, humerus, and scapula, which work synergistically to form a complex articulation that is essential for use of the upper extremity. The shoulder girdle is the most common location for primary and secondary bone tumors in the upper extremity, and following resection of these tumors, reconstruction of the upper extremity is challenging. Compared with those in the lower extremity, reconstructive techniques in the upper extremity have historically been unreliable and fraught with complications and poor functional outcomes. Newer reconstructive techniques using reverse total shoulder arthroplasty and functional muscle flaps have shown promise to improve outcomes while reducing complications for proximal humerus reconstructions. Despite these advancements, reconstruction following scapulectomy remains challenging and is still associated with more frequent complications and compromised function.

Esclerosis bilateral de huesos largos: enfermedad de Erdheim-Chester. Reporte de un caso / Bilateral long bone sclerosis: Erdheim-Chester disease. Case report

La enfermedad de Erdheim-Chester (EEC) es una patología poco frecuente, caracterizada por presentar infiltración xantogranulomatosa sistémica, con afección de diversos sistemas incluido el óseo. La EEC se encuentra descripta dentro de las enfermedades osteocon-densantes (EO), las cuales se reconocen por presentar aumento de la masa ósea y compromiso tanto de huesos largos como planos. La presentación clínica de la EEC es variada: puede presentar desde un curso indolente hasta manifestaciones multisistémicas. Las características radiológicas son de gran importancia para establecer su diagnóstico. Presentamos una paciente con EEC, con esclerosis bilateral de huesos largos, que exhibe algunas características diferenciales con relación a otros casos reportados: a) afectación exclusivamente ósea a 10 años de evolución, b) compromiso bilateral y simétrico de distinta magnitud, c) esclerosis cortical endóstica y perióstica, d) signos radiológicos sugestivos de periostitis, d) ausencia de compromiso metafisario, e) ausencia de actividad metabólica de las lesiones en las imágenes de 18F-FDG PET/CT.Conclusión: la presencia de lesiones osteocondensantes bilaterales exclusivamente en huesos largos deben hacer sospechar EEC. La ausencia de compromiso metafisario y de actividad metabólica en 18F-FDG PET/CT ha sido raramente descripta. (AU)

Erdheim - Chester disease (ECD) is a rare disease, characterized by systemic xanthogranulomatous infiltration, with involvement of various organs including bone. ECD is described within the sclerosing bone disorders, which are recognized for presenting increased bone mass and involvement of both long and flat bones. The clinical presentation of ECD is diverse, ranging from an asymptomatic course to multisystemic manifestations. Radiological features are of great importance to establish the diagnosis. We describe here a patient with ECD, with bilateral sclerosis of long bones that presents some differential characteristics in relation to other reported cases: a) exclusively bone involvement at 10 years of evolution, b) bilateral and symmetric involvement of different magnitude, c) endosteal and periosteal cortical sclerosis d) radiological signs suggestive of periostitis, d) absence of metaphyseal involvement, e) absence of metabolic activity of the lesions in 18F-FDG PET/CT.Conclusion: the presence of bilateral osteosclerosis exclusively in long bones should lead to suspect ECD. The absence of metaphyseal involvement and metabolic activity in 18F-FDG PET/CT have been rarely described. (AU)

Outcomes of proximal humeral reconstruction with cemented osteoarticular allograft in pediatric patients: a retrospective cohort study.

BACKGROUND: There is no agreement on the best choice of proximal humeral reconstruction following tumor resection in pediatric patients. We reviewed the functional outcomes, oncologic outcomes, and surgical complications in pediatric patients after proximal humeral reconstruction with cemented osteoarticular allograft. METHODS: Eighteen patients aged 8-13 years who underwent proximal humeral osteoarticular allograft reconstruction following resection of primary bone sarcoma were included. The mean follow-up period was 88 ± 31.7 months. At the last follow-up assessment, limb function was evaluated based on shoulder range of motion, Musculoskeletal Tumor Society score, and Toronto Extremity Salvage Score. Tumor recurrence and postoperative complications were extracted from the patients' medical records. RESULTS: Mean active forward flexion of the shoulder was 38° ± 18°. Mean active abduction was 48° ± 18°. Mean active external rotation was 23° ± 9°. The mean Musculoskeletal Tumor Society score was 73.4% ± 11.2%. The mean Toronto Extremity Salvage Score was 75.6% ± 12.9%. Local recurrence occurred in 1 patient. Metastasis developed after the operation in 2 additional patients. We recorded 6 postoperative complications in this series, including 1 superficial infection, 1 late-onset deep infection, 1 allograft fracture, 2 cases of nonunion, and 2 cases of shoulder instability. Two complications required allograft removal. CONCLUSION: In pediatric patients, reconstruction of the proximal humerus with cemented osteoarticular allograft results in acceptable oncologic and functional outcomes while the postoperative complication rate seems to be lower than that of other available techniques.

Are Vascularized Fibula Autografts a Long-lasting Reconstruction After Intercalary Resection of the Humerus for Primary Bone Tumors?

BACKGROUND: A vascularized fibula graft (VFG) is the vascular autograft most frequently used to restore large segmental long bone defects, particularly in the upper limb. Because the use of a vascularized fibula involves an operation in an uninvolved extremity with potential morbidity, it is important to document that this type of reconstruction is successful in restoring function to the humerus. However, the long-term results of VFG after intercalary resection of the humeral diaphysis for bone tumors are still unknown. QUESTIONS/PURPOSES: (1) What was the complication rate of reconstruction? (2) What was the functional result after surgical treatment, as assessed by the Musculoskeletal Tumor Society (MSTS) score, the American Shoulder and Elbow Society (ASES) score, and Constant score? (3) What was the survivorship of these grafts free from revision and graft removal at 5, 10, and 15 years? METHODS: Between 1987 and 2021, 127 patients were treated at our institution with en bloc resection for a primary malignant or an aggressive benign bone tumor of the humerus; we excluded patients treated with extra-articular resection or amputation. Of those, 14% (18 of 127) were treated with intercalary resection of the humeral diaphysis for primary bone tumors and reconstruction with VFG, with or without a bulk allograft, and were analyzed in this retrospective study. Generally, our indications for reconstruction with VFG are intercalary resection of the humerus for primary malignant or aggressive benign bone tumors in patients with long life expectancy and high functional demands, in whom adequate bone stock of the proximal and distal epiphysis can be preserved. In 13 patients, VFG was used alone, whereas in five patients, a massive allograft was used. Our policy was to use VFG combined with a massive allograft in patients undergoing juxta-articular joint-sparing resections in which proximal osteotomy was performed close to the anatomic neck of the humerus to obtain more stable fixation and better tendinous reattachment of the rotator cuff and deltoid. All 18 patients who were treated with a VFG were available for follow-up at a minimum of 2 years (median follow-up 176 months, range 26 to 275 months), and although three have not been seen in the past 5 years and are not known to have died, they had 172, 163, and 236 months of follow-up, and were included. The median age at surgery was 25 years (range 2 to 63 years), the median humeral resection length was 15 cm (range 8 to 21 cm), and the median fibular length was 16 cm (range 12 to 23 cm). Complications and functional scores were ascertained by chart review that was performed by an individual not involved in patient care. Functional results were assessed with the MSTS score (range 0 to 30), the ASES score (range 0 to 100), and the Constant score (range 0% to 100%). Survivorship was estimated using a Kaplan-Meier survivorship estimator, which was suitable because there were few deaths in this series. RESULTS: Seven patients underwent a revision procedure (one radial nerve transient palsy because of screw impingement, four nonunions in three patients with one humeral head avascular necrosis, treatment for screw-related pain in one patient, and two VFG fractures), and one patient underwent VFG removal. Donor site complications were observed in four patients (one ankle valgus deformity and three claw toes-the first toe in two patients and the other toes in the third). At the final clinical control, at a median follow-up of 176 months (range 26 to 275 months), the median MSTS score was 30 of 30 (range 28 to 30), the median ASES score was 98.3 (range 93 to 100), and the median Constant score was 93.5% (range 79% to 100%). Revision-free survival was 71% (95% CI 53% to 96%) at 5 years and 57% (95% CI 37% to 88%) at 10 and 15 years; VFG removal-free survival was 94% (95% CI 83% to 100%) at 5, 10, and 15 years. CONCLUSION: VFG appears to be an effective reconstructive option after humeral intercalary resection for primary bone tumors. These are complex procedures and should be performed by an experienced team of surgeons who recognize that complications may occur frequently in the first years after the procedure. The frequency of mechanical complications observed in the first 5 years postoperatively may be lessened by using long spanning-plate fixation, and if successful, this reconstruction provides a long-term, durable reconstruction with excellent functional results. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Humeral intracondylar fissures and intracondylar sclerosis are common CT findings in the limb contralateral to a humeral condylar fracture in French bulldogs and spaniel breeds.

French bulldogs (FBD) are reported to be at an increased risk of developing humeral condylar fractures (HCF). Spaniel breeds have been reported to be at increased risk of HCF due to a high prevalence of humeral intracondylar fissures (HIF), which can predispose to fracture. The aims of this retrospective, single center, observational study were twofold. First, to compare the signalment, fracture configuration, and etiology of populations of FBD and spaniel breeds presenting with HCF at a single hospital. Second, to evaluate the computed tomographic (CT) findings of the contralateral elbow joints of FBD and spaniel breeds presenting with HCF for concomitant pathology. FBDs were overrepresented for HCF, most commonly presenting when skeletally immature, with a median age of 3.7 months. Fractures of the lateral condyle were the most common configuration for both breed groups. Sclerosis at the fracture site was identified in 62% of FBD and 95% of spaniels undergoing CT scans. Humeral intracondylar fissures and intracondylar sclerosis were commonly observed in the contralateral elbows of FBD (44% and 50%, respectively) and spaniel breeds (58% and 95%, respectively). Medial coronoid pathology, elbow incongruency, and periarticular osteophytes were not identified in the contralateral elbows of FBD but were identified in 29%, 4%, and 20% of spaniels, respectively. The high prevalence of HIF in the FBD group may be a predisposing factor for HCF in this breed.

What Is the Prosthetic Survival After Resection and Intercalary Endoprosthetic Reconstruction for Diaphyseal Bone Metastases of the Humerus and Femur?

BACKGROUND: Large metastatic lesions of the diaphysis can cause considerable pain and result in difficult surgical challenges. Resection and cemented intercalary endoprosthetic reconstruction offer one solution to the problem, but it is an extensive operation that might not be tolerated well by a debilitated patient. The risk of aseptic loosening and revision after intercalary endoprosthetic replacement has varied in previous reports, which have not examined the risk of revision in the context of patient survival. QUESTIONS/PURPOSES: (1) In a small case series from one institution, what is the survivorship of patients after cemented intercalary endoprosthetic replacement for diaphyseal metastasis, and what is the cumulative incidence of revision for any reason? (2) What are the complications associated with cemented intercalary reconstruction? (3) What is the functional outcome after the procedure as assessed by the MSTS93 score? METHODS: We retrospectively studied 19 patients with diaphyseal long bone metastases who were treated with resection and cemented intercalary endoprosthetic reconstruction by five participating surgeons at one referral center from 2006 to 2017. There were 11 men and eight women with a median age of 59 years (range 46 to 80 years). The minimum follow-up required for this series was 12 months; however, patients who reached an endpoint (death, radiographic loosening, or implant revision) before that time were included. One of these 19 patients was lost to follow-up but was not known to have died. The median follow-up was 24 months (range 0 to 116 months). Eight of the 19 patients presented with pathologic fractures. Ten of 19 lesions involved the femur, and nine of 19 were in the humerus. The most common pathologic finding was renal cell carcinoma (in 10 of 19). Survival estimates of the patients were calculated using the Kaplan-Meier method. A competing risks estimator was used to evaluate implant survival, using death of the patient as the competing risk. We also estimated the cumulative incidence of aseptic loosening in a competing risk analysis. Radiographs were analyzed for radiolucency at the bone-cement-implant interfaces, fracture, integrity of the cement mantle, and component position stability. Complications were assessed using record review that was performed by an individual who was not involved in the initial care of the patients. Functional outcomes were assessed using the MSTS93 scoring system. RESULTS: Patient survivorship was 68% (95% CI 50% to 93%) at 1 year, 53% (95% CI 34% to 81%) at 2 years, and 14% (95% CI 4% to 49%) at 5 years; the median patient survival time after reconstruction was 25 months (range 0 to 116 months). In the competing risk analysis, using death as the competing risk, the cumulative incidence of implant revision was 11% (95% CI 2% to 29%) at 1 year and 16% (95% CI 4% to 36%) at 5 years after surgery; however, the cumulative incidence of aseptic loosening (with death as a competing risk) was 22% (95% CI 6% to 43%) at 1 year and 33% (95% CI 13% to 55%) at 5 years after surgery. Other complications included one patient who died postoperatively of cardiac arrest, one patient with delayed wound healing, two patients with bone recurrence, and one patient who experienced local soft tissue recurrence that was excised without implant revision. Total MSTS93 scores improved from a mean of 12.6 ± 8.1 (42% ± 27%) preoperatively to 21.5 ± 5.0 (72% ± 17%) at 3 months postoperatively (p < 0.001) and 21.6 ± 8.5 (72% ± 28%) at 2 years postoperatively (p = 0.98; 3 months versus 2 years). CONCLUSION: Resection of diaphyseal metastases with intercalary reconstruction can provide stability and short-term improvement in function for patients with advanced metastatic disease and extensive cortical destruction. Aseptic loosening is a concern, particularly in the humerus; however, the competing risk analysis suggests the procedure is adequate for most patients, because many in this series died of disease without undergoing revision. LEVEL OF EVIDENCE: Level IV, therapeutic study .