Survival and failure modes of the Compress® spindle and expandable distal femur endoprosthesis among pediatric patients: A multi-institutional study.

BACKGROUND: Expandable endoprostheses can be used to equalize limb length for pediatric patients requiring reconstruction following large bony oncologic resections. Outcomes of the Compress® Compliant Pre-Stress (CPS) spindle paired with an Orthopedic Salvage System expandable distal femur endoprosthesis have not been reported. METHODS: We conducted a multi-institutional retrospective study of pediatric patients with distal femoral bone sarcomas reconstructed with the above endoprostheses. Statistical analysis utilized Kaplan-Meier survival technique and competing risk analysis. RESULTS: Thirty-six patients were included from five institutions. Spindle survivorship was 86.3% (95% confidence interval [CI], 67.7-93.5) at 10 years. Two patients had a failure of osseointegration (5.7%), both within 12 months. Twenty-two (59%) patients had 70 lengthening procedures, with mean expansions of 3.2 cm (range: 1-9) over 3.4 surgeries. The expandable mechanism failed in eight patients with a cumulative incidence of 16.1% (95% CI, 5.6-31.5) at 5 years. Twenty-nine patients sustained International Society of Limb Salvage failures requiring 63 unplanned surgeries. Periprosthetic joint infection occurred in six patients (16.7%). Limb preservation rate was 91% at 10 years. CONCLUSIONS: There is a high rate of osseointegration of the Compress® spindle among pediatric patients when coupled with an expandable implant. However, there is a high rate of expansion mechanism failure and prosthetic joint infections requiring revision surgery. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Secondary aneurysmal bone cysts and associated primary lesions: imaging features of 49 cases.

PURPOSE: To describe the imaging, anatomic, and clinical features of a series of secondary aneurysmal bone cysts (ABC) and to ascertain their most commonly associated primary bone lesions. METHODS: Forty-nine cases of histopathologically proven secondary ABCs were retrospectively reviewed. Demographic data and clinical history were obtained. Radiographic, computed tomographic, magnetic resonance, and nuclear medicine imaging were analyzed. Lesion location, imaging characteristics, and associated primary lesions were documented. Linear regression analysis and Chi-squared testing was performed for statistical analysis. RESULTS: Twenty-four males and 25 females were included, with an age range of 8-79 years (mean 29.7 + - 4.5 years). Eleven types of primary bone lesion were identified, with giant-cell tumor (n = 17, 35%), chondroblastoma (n = 11, 22%), fibrous dysplasia (n = 6, 12%), osteoblastoma (n = 4, 8%) and osteosarcoma (n = 4, 8%) being the most frequent. The lesions involved chiefly the long bone epiphyses (n = 25, 51%). Secondary ABC imaging findings and locations most closely approximated those of their primary counterparts, although fluid-fluid levels were seen at a higher frequency than previously reported in primary chondroblastoma (9/11, 82%), fibrous dysplasia (2/6, 33%), osteoblastoma (4/4, 100%), osteosarcoma (3/4, 75%), and chondromyxoid fibroma (1/2, 50%). CONCLUSION: The most common primary lesions associated with secondary ABC were giant cell tumor and chondroblastoma, located in the long bone epiphyses. The majority of the secondary ABCs demonstrate predominant imaging characteristics typical of the primary bone lesions, but with a higher presence of fluid-fluid levels.

Musculoskeletal Infection in Orthopaedic Oncology: Assessment of the 2018 International Consensus Meeting on Musculoskeletal Infection.

BACKGROUND: The first International Consensus Meeting (ICM) on Musculoskeletal Infection convened in 2013 in order to provide agreement on the prevention, the diagnosis, and the treatment of surgical site infection (SSI) and periprosthetic joint infection (PJI). Recognizing the added susceptibility of orthopaedic oncology patients to SSI and PJI, the second ICM in 2018 included questions and corresponding recommendations from this subspecialty of orthopaedics. METHODS: The 13 steps of the Delphi method were followed over the course of 26 months, starting in June 2016. From July 25 to 27, 2018, delegates from 93 countries convened at Thomas Jefferson University in Philadelphia, Pennsylvania. Delegates were divided into their subspecialty workgroups, where questions and recommendations were discussed, modified, and subsequently voted upon. The level of consensus measured the agreement among the delegates on the basis of the voting results. The level of evidence that accompanied each question and recommendation was dependent on the types of studies that were reviewed for each question and the number of flaws that were present in those studies. RESULTS: There were 30 orthopaedic oncology questions and recommendations that were voted on by 14 delegates with expertise in either orthopaedic oncology or infectious disease. Twenty-six (87%) of the questions were unanimous among the delegates. The remaining 13% (n = 4) were agreed upon by 93% of the delegates, with 7% of the delegates abstaining from the vote. CONCLUSIONS: The inclusion of orthopaedic oncology in the 2018 ICM on Musculoskeletal Infection was particularly important because of the high rate of SSI and PJI following these procedures. Despite there being strong consensus among voting delegates, these recommendations are based on limited levels of evidence and tend to reflect the recommendations from hip and knee arthroplasty. We hope that high-quality prospective studies in the field of orthopaedic oncology are available for the third ICM.

Factors Associated with Osteoid Osteoma Recurrence after CT-Guided Radiofrequency Ablation.

PURPOSE: To identify clinical and imaging variables associated with symptomatic recurrence of osteoid osteomas (OOs) treated with computerized tomography (CT)-guided radiofrequency (RF) ablation. MATERIALS AND METHODS: Seventy-one patients treated with the use of CT-guided RF ablation for OO at a single institution from July 2005 to May 2018 were included in this retrospective cohort analysis. Clinical data, including patient age, sex, race, and clinical outcomes, were collected from institutional electronic health records and telephone follow-up. Imaging variables regarding tumor characteristics were gathered from imaging reports and a blinded review of preprocedural images by an experienced musculoskeletal radiologist. Logistic regression, Cox proportional hazards, and Kaplan-Meier analyses were used to identify variables that are significantly associated with symptomatic recurrence, which was defined as pain occurring > 2 weeks after RF ablation. RESULTS: Ten patients (14.1%) experienced symptomatic recurrence at a median of 21.5 months after RF ablation. Univariable logistic regression classified young age (≤ 13 years), female sex, maximum tumor length, and "eccentricity index" (EI) ≥ 3 as predictive variables significantly associated with symptomatic recurrence. Multivariable logistic regression identified female sex and EI ≥ 3 to be significant predictors for symptomatic recurrence. A multivariable proportional hazards Cox regression of time to recurrence revealed EI ≥ 3 to be the only significant predictor of symptomatic recurrence. CONCLUSIONS: Female patients with OOs with an EI ≥ 3 have a greater risk of symptomatic recurrence following RF ablation. The EI is a useful tool to identify OOs with elongated 3-dimensional morphology, which may warrant more extensive ablation.

Cutibacterium (formerly Propionibacterium) acnes clavicular infection.

Cutibacterium (formerly Propionibacterium) acnes13, 16 is a slow growing, gram-positive bacteria that is naturally found in higher concentrations as skin flora on the chest and back, as well as in other areas with greater numbers of hair follicles.25, 37 Most of the reported cases of C. acnes shoulder girdle infection follow arthroplasty surgery,18, 20, 26, 27, 32, 35 which then often requires debridement, administration of intravenous antibiotics, and surgical revision of the implanted device.12, 15, 21, 28-30 In a recent study, 56% of 193 shoulder revisions had a positive culture, 70% of which grew C. acnes.30 Despite the relatively common presumed association of C. acnes humeral osteomyelitis with prosthetic infection, infection of the scapula or clavicle secondary to C. acnes is rare.4, 23, 36 Osteomyelitis of the clavicle involving any organism is also an uncommon event that can arise spontaneously via presumed hematogenous spread, or secondary to open fractures or internal fixation.6, 33 The most commonly found organism in clavicular osteomyelitis is Staphylococcus aureus.9 We here report two cases of clavicular infection secondary to C. acnes that were not associated with implants.

Soft Tissue Sarcoma, Version 2.2018, NCCN Clinical Practice Guidelines in Oncology.

Soft tissue sarcomas (STS) are rare solid tumors of mesenchymal cell origin that display a heterogenous mix of clinical and pathologic characteristics. STS can develop from fat, muscle, nerves, blood vessels, and other connective tissues. The evaluation and treatment of patients with STS requires a multidisciplinary team with demonstrated expertise in the management of these tumors. The complete NCCN Guidelines for STS provide recommendations for the diagnosis, evaluation, and treatment of extremity/superficial trunk/head and neck STS, as well as intra-abdominal/retroperitoneal STS, gastrointestinal stromal tumors, desmoid tumors, and rhabdomyosarcoma. This portion of the NCCN Guidelines discusses general principles for the diagnosis, staging, and treatment of STS of the extremities, superficial trunk, or head and neck; outlines treatment recommendations by disease stage; and reviews the evidence to support the guidelines recommendations.

NCCN Guidelines Insights: Bone Cancer, Version 2.2017.

The NCCN Guidelines for Bone Cancer provide interdisciplinary recommendations for treating chordoma, chondrosarcoma, giant cell tumor of bone, Ewing sarcoma, and osteosarcoma. These NCCN Guidelines Insights summarize the NCCN Bone Cancer Panel's guideline recommendations for treating Ewing sarcoma. The data underlying these treatment recommendations are also discussed.

Intra-articular osteoid osteoma at the femoral trochlea treated with osteochondral autograft transplantation.

We present the case of an intra-articular osteoid osteoma at the femoral trochlea. Intra-articular osteoid osteoma can present a diagnostic challenge both clinically and with imaging because it presents differently from the classic cortical osteoid osteoma. Given the lesion's proximity to overlying cartilage, the patient underwent resection of the lesion with osteochondral autograft transplantation at the surgical defect. A comprehensive literature review and discussion of intra-articular osteoma will be provided.

Multiple hereditary exostoses: A pseudoaneurysm masquerading as tumor.

Multiple hereditary exostoses is an autosomal dominant condition characterized by numerous benign osteochondromas. Complications are rare and can include deformity, growth abnormality, fracture, adventitial bursa formation, local mass effect on a nerve, malignant degeneration, and vascular complications including stenosis, occlusion, arteriovenous fistula, and pseudoaneurysm. We present a case of multiple hereditary exostoses leading to a deep femoral artery pseudoaneurysm in the proximal medial thigh with subsequent rupture and hematoma, masquerading as tumor.

Malignant Transformation of an Aneurysmal Bone Cyst to Fibroblastic Osteosarcoma.

Aneurysmal bone cysts are uncommon primary bone tumors typically regarded as histologically and clinically benign. Malignant transformation of these lesions occurs almost exclusively in the context of prior radiation exposure. However, 4 cases of an osteosarcoma developing without prior radiation exposure have been reported. In this article, we report a fifth case of degeneration of an aneurysmal bone cyst to a fibroblastic osteosarcoma. In addition to reviewing the earlier cases, we describe the radiologic, pathologic, and immunohistochemical basis of this diagnosis.

Giant Cell Tumor of Bone: Documented Progression over 4 Years from Its Origin at the Metaphysis to the Articular Surface.

The exact location of origin for giant cell tumors of bone (GCTB) remains controversial, as lesions are not routinely imaged early but rather late when the tumor is large and clinically symptomatic. At the time of diagnosis, GCTB are classically described as lucent, eccentric lesions with nonsclerotic margins, located within the epiphysis to a greater extent than the metaphysis. Here we present a case of a biopsy proven GCTB initially incidentally seen on MRI as a small strictly metaphyseal lesion, which over the course of several years expanded across a closed physis to involve the epiphysis and abut the articular surface/subchondral bone plate.

Soft Tissue Sarcoma, Version 2.2016, NCCN Clinical Practice Guidelines in Oncology.

Soft tissue sarcomas (STS) are rare solid tumors of mesenchymal cell origin that display a heterogenous mix of clinical and pathologic characteristics. STS can develop from fat, muscle, nerves, blood vessels, and other connective tissues. The evaluation and treatment of patients with STS requires a multidisciplinary team with demonstrated expertise in the management of these tumors. The complete NCCN Guidelines for Soft Tissue Sarcoma (available at NCCN.org) provide recommendations for the diagnosis, evaluation, and treatment of extremity/superficial trunk/head and neck STS, as well as intra-abdominal/retroperitoneal STS, gastrointestinal stromal tumor, desmoid tumors, and rhabdomyosarcoma. This manuscript discusses guiding principles for the diagnosis and staging of STS and evidence for treatment modalities that include surgery, radiation, chemoradiation, chemotherapy, and targeted therapy.

How Often Does Spindle Failure Occur in Compressive Osseointegration Endoprostheses for Oncologic Reconstruction?

BACKGROUND: Compressive osseointegration is a promising modality for limb salvage in distal femoral oncologic tumors. However, few studies have explored short-term survival rates in a large patient cohort of distal femur compressive endoprostheses or highlighted the risk factors for spindle failures. QUESTIONS/PURPOSES: We asked: (1) What is the frequency of compressive osseointegration spindle failure in distal femoral reconstructions? (2) What are the characteristics of rotational failure cases with distal femur compressive osseointegration endoprostheses? (3) What are the risk factors for mechanical and rotational failure of distal femur compressive osseointegration implantation? (4) What are other modalities of failure or causes of revision surgery, which affect patients undergoing distal femur compressive osseointegration implantation for oncologic reconstruction? METHODS: Between 1996 and 2013, 127 distal femoral reconstructions with the Compress(®) prosthesis were performed in 121 patients. During that time, 116 Compress(®) prostheses were implanted for aggressive primary tumors of the distal femur and/or failure of previous oncologic reconstruction. This approach represented approximately 91% of the distal femoral reconstructions performed during that time. Of the patients with prostheses implanted, four patients (four of 116, 3%) had died, and 37 (37 of 116, 32%) were lost to followup before 24 months. The median followup was 84 months (range, 24-198 months), and 71 patients (66% of all patients) were seen within the last 3 years. A retrospective chart review was performed to determine failure modality as defined by radiographs, clinical history, and intraoperative findings. Risk factors including age, sex, BMI, resection length, and perioperative chemotherapy were analyzed to determine effect on spindle and rotational failure rates. Survival analysis was determined using the Kaplan-Meier estimator. Differences in survival between groups were analyzed using the log rank test. Risk factors were determined using Cox proportional hazard modeling. RESULTS: Spindle survival at 5 and 10 years was 91% (95% CI, 82%-95%). Survival rates from rotational failure at 5 and 10 years were 92% (95% CI, 83%-96%); the majority of failures occurred within the first 2 years postoperatively and were the result of a twisting mechanism of injury. With the numbers available, none of the potential risk factors examined were associated with mechanical failure. The 5-year and 10-year all-cause revision-free survival rates were 57% (95% CI, 44%-67%) and 50% (95% CI, 36%-61%), respectively. CONCLUSIONS: Distal femur compressive osseointegration is a viable method for endoprosthetic reconstruction. Rotational failure is rare with the majority occurring early. No variables were found to correlate with increased risk of mechanical failure. More research is needed to evaluate methods of preventing mechanical and rotational failures in addition to other common causes of revision such as infection in these massive endoprosthetic reconstructions. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Intraoperative Radiotherapy in the Management of Locally Recurrent Extremity Soft Tissue Sarcoma.

Purpose. To investigate the efficacy and morbidity of limb-sparing surgery with intraoperative radiotherapy (IORT) for patients with locally recurrent extremity soft tissue sarcoma (ESTS). Methods and Materials. Twenty-six consecutively treated patients were identified in a single institution retrospective analysis of patients with locally recurrent ESTS treated with IORT following salvage limb-sparing resection from May 2000 to July 2011. Fifteen (58%) patients received external beam radiotherapy (EBRT) prior to recurrence (median dose 63 Gy), while 11 (42%) patients received EBRT following IORT (median dose 52 Gy). The Kaplan-Meier product limit method was used to estimate disease control and survival and subsets were compared using a log rank statistic, Cox's regression model was used to determine independent predictors of disease outcome, and toxicity was reported according to CTCAE v4.0 guidelines. Results. With a median duration of follow-up from surgery and IORT of 34.9 months (range: 4 to 139 mos.), 10 patients developed a local recurrence with 4 subsequently undergoing amputation. The 5-year estimate for local control (LC) was 58% (95% CI: 36-75%), for amputation-free was 81% (95% CI: 57-93%), for metastasis-free control (MFC) was 56% (95% CI: 31-75%), for disease-free survival (DFS) was 35% (95% CI: 17-54%), and for overall survival (OS) was 50% (95% CI: 24-71%). Prior EBRT did not appear to influence disease control (LC, p = 0.74; MFC, p = 0.66) or survival (DFS, p = 0.16; OS, p = 0.58). Grade 3 or higher acute and late toxicities were reported for 6 (23%) and 8 (31%) patients, respectively. The frequency of both acute and late grade 3 or higher toxicities occurred equally between patients who received EBRT prior to or after IORT. Conclusions. IORT in combination with oncologic resection of recurrent ESTS yields good rates of local control and limb-salvage with acceptable morbidity. Within the limitations of small subsets, these data suggest that prior EBRT does not significantly influence disease control or toxicity.

Gastrointestinal stromal tumors, version 2.2014.

Gastrointestinal stromal tumors (GIST) are the most common soft tissue sarcoma of the gastrointestinal tract, resulting most commonly from KIT or platelet-derived growth factor receptor α (PDGFRα)-activating mutations. These NCCN Guideline Insights highlight the important updates to the NCCN Guidelines for Soft Tissue Sarcoma specific to the management of patients with GIST experiencing disease progression while on imatinib and/or sunitinib.

Soft tissue sarcoma, version 2.2014.

These NCCN Guidelines Insights highlight the important updates to the NCCN Guidelines for Soft Tissue Sarcoma (STS) specific to the role of radiation therapy in the management of patients with retroperitoneal/intra-abdominal STS. The guidelines have also included recommendations for genetic testing and counseling for patients with a clinical and/or family history of genetic cancer syndromes associated with a predisposition for the development of STS.

Bone cancer.

Primary bone cancers are extremely rare neoplasms, accounting for fewer than 0.2% of all cancers. The evaluation and treatment of patients with bone cancers requires a multidisciplinary team of physicians, including musculoskeletal, medical, and radiation oncologists, and surgeons and radiologists with demonstrated expertise in the management of these tumors. Long-term surveillance and follow-up are necessary for the management of treatment late effects related to surgery, radiation therapy, and chemotherapy. These guidelines discuss the management of chordoma, giant cell tumor of the bone, and osteosarcoma.

Prevention of Orthopaedic Implant Infection in Patients Undergoing Dental Procedures.

The Prevention of Orthopaedic Implant Infection in Patients Undergoing Dental Procedures evidence-based clinical practice guideline was codeveloped by the American Academy of Orthopaedic Surgeons (AAOS) and the American Dental Association. This guideline replaces the previous AAOS Information Statement, "Antibiotic Prophylaxis in Bacteremia in Patients With Joint Replacement," published in 2009. Based on the best current evidence and a systematic review of published studies, three recommendations have been created to guide clinical practice in the prevention of orthopaedic implant infections in patients undergoing dental procedures. The first recommendation is graded as Limited; this recommendation proposes that the practitioner consider changing the long-standing practice of routinely prescribing prophylactic antibiotic for patients with orthopaedic implants who undergo dental procedures. The second, graded as Inconclusive, addresses the use of oral topical antimicrobials in the prevention of periprosthetic joint infections. The third recommendation, a Consensus statement, addresses the maintenance of good oral hygiene.