Alexander H. Jinnah

Hidradenocarcinoma presenting as soft tissue mass: Case report with cytomorphologic description, histologic correlation, and differential diagnosis

Hidradenocarcinoma (HAC) is a rare adenexal tumor with a propensity for the head and neck region and extremities. We report a case of hidradenocarcinnoma in a 56‐year‐old woman with a mass on her right palm sampled by fine‐needle aspiration and later confirmed on histological examination. Fine‐needle aspiration cytology revealed a dual population of cells including polyhedral eosinophilic cells and glycogen containing cells with pale/clear cytoplasm. The nuclei were pleomorphic with prominent nucleoli. Occassional papillary structures were identified on the cell block material. A series of immunohistochemical stains were performed and an adnexal neoplasm was suggested. The mass was resected. On histologic sections, infiltration into the adjacent soft tissue was identified. After an additional series of immunohistochemical stains, the diagnosis was confirmed as a HAC. Herein, we present our findings and discuss the differential diagnoses. Diagn. Cytopathol. 2016;44:438–441.

Proving Osteoinductive Potential of a Decellularized Xenograft Bone Substitute

Background Large bone defects remain a major clinical challenge for orthopaedic surgeons. Tissue engineered bone grafts have garnered increased attention as a solution to this problem. One ideal property of any bone graft is osteoinductivity or the ability to stimulate progenitor cell differentiation into a bone forming lineage. Questions Is the osteoinductive potential of a porcine bone xenograft maintained in vitro after undergoing a novel decellularization and oxidation process? Are porcine bone scaffolds osteoinductive in an in vivo animal model? Methods In Vitro – C2C12 pre-osteoblasts were seeded on the scaffold or a commercial grade demineralized bone matrix (DBM) to study osteogenic differentiation and compare osteoinductive potential. MC3T3-E1 pre-osteoblasts were seeded on the scaffold and compared to a control monolayer to identify early markers of osteogenic differentiation. In Vivo – MC3T3-E1-seeded scaffolds were implanted subcutaneously in mice and assessed for markers of early osteogenic differentiation, new bone formation (micro-computed tomography and histological assessment), and vascular infiltration (histology). Results Osteoinductive potential was demonstrated in in vitro experiments by similar osteogenic marker expression compared to DBM and significantly greater expression than a control monolayer. Osteoinductivity was confirmed with in vivo experiments showing both new bone formation and vascular infiltration. Conclusion Porcine bone maintains osteoinductive properties after decellularization and oxidation. Clinical Relevance This construct could potentially serve as a bone graft substitute maintaining the osteoinductive potential of native bone. The unrestricted supply and controlled donor biology may satisfy a large clinical need for orthopaedic cases requiring bone grafting.

A percutaneous, minimally invasive annulus fibrosus needle puncture model of intervertebral disc degeneration in rabbits:

Purpose: Various animal models have been proposed to mimic the pathophysiologic process of intervertebral disc degeneration, a leading cause of back pain. The purpose of this study is to describe a minimally invasive technique via percutaneous needle puncture of the annulus fibrosus in New Zealand white rabbits. Methods: Under fluoroscopic guidance, an 18-gauge spinal needle was inserted 2 cm lateral to the midline spinous process. The needle was slowly advanced at approximately 45° angle until it was adjacent to the L5/L6 disc space. Lateral and anteroposterior views were used to verify correct needle position before advancing into the nucleus pulposus. The rabbits underwent weekly X-rays for 4 weeks to assess disc height index. MRI T2 relaxation was evaluated at week four to assess morphological changes. Discs were histologically graded on a 12-point scale to assess degeneration and compared to discs obtained from uninjured rabbits. Results: There were no complications associated with the percutaneous needle puncture procedure. All animals survived the duration of the experiment. Four weeks after injury, the disc height had progressively narrowed to approximately 50% of baseline. MRI assessment at the 4-week time point demonstrated a mean T2 relaxation time at the L5/L6 level that was 20.9% of the T2 relaxation time at the uninjured L4/L5 disc level (p < 0.001). Histological analysis demonstrated lamellar disorganization of the annulus and decreased cellularity and proteoglycan content within the injured nucleus compared to uninjured control discs. Conclusion: The present study demonstrated a reliable technique of inducing an annular tear via a percutaneous needle puncture. Compared to open surgical approaches, the percutaneous model produces similar progressive disc degeneration while minimizing harm to the animal subjects. Clinical Relevance: The present study establishes a technique for the introduction of novel therapeutic agents to treat disc degeneration that may translate to future clinical trials.

Previous History of Breast Cancer Increases Rates of Pulmonary Embolism and Costs after Total Knee Arthroplasty: An Evaluation of 185,114 Matched Patients

&NA; Risk factors for adverse events after total knee arthroplasty (TKA) relating to malignancy have not been well studied. Thus, the purpose of this study was to conduct a retrospective case‐control outcome and cost analysis after TKA in this population. Patients with a history of breast cancer (BrCa) were identified based on the International Classification of Disease 9th revision codes. An age‐ and sex‐matched cohort was also identified of patients without a history of BrCa. Complications, length of stay, comorbidity burden, and reimbursements were tracked at 90 days. Each cohort comprised 92,557 patients. Length of stay was similar between cohorts (p = 0.627). Comorbidity status and incidence of pulmonary embolism (PE), lower extremity ultrasound, and chest computed tomography (CT) use were higher in patients with a history of BrCa (p < 0.05 for all). Control patients had a lower incidence of acute myocardial infarction (0.14 vs. 0.21%; p < 0.001). Surgical complications were similar. The 90‐day reimbursements were greater in patients with a history of BrCa (US

A Decellularized Porcine Xenograft-Derived Bone Scaffold for Clinical Use as a Bone Graft Substitute: A Critical Evaluation of Processing and Structure

13,990 vs. US

Emerging and Established Models of Bone Metastasis

13,033 for controls; p = 0.021). Surgeons should be aware of the increased risk of PE after TKA in patients with a history of BrCa as well as increased 90‐day costs, which warrant great attention.

Editorial on “Determination of the accuracy of navigated kinematic unicompartmental knee arthroplasty: a 2-year follow-up”

Background: Bone grafts are used in approximately one half of all musculoskeletal surgeries. Autograft bone is the historic gold standard but is limited in supply and its harvest imparts significant morbidity to the patient. Alternative sources of bone graft include allografts, synthetics and, less commonly, xenografts which are taken from animal species. Xenografts are available in unlimited supply from healthy animal donors with controlled biology, avoiding the risk of human disease transmission, and may satisfy current demand for bone graft products. Methods: In the current study, cancellous bone was harvested from porcine femurs and subjected to a novel decellularization protocol to derive a bone scaffold. Results: The scaffold was devoid of donor cellular material on histology and DNA sampling (p < 0.01). Microarchitectural properties important for osteoconductive potential were preserved after decellularization as shown by high resolution imaging modalities. Proteomics data demonstrated similar profiles when comparing the porcine bone scaffold against commercially available human demineralized bone matrix approved for clinical use. Conclusion: We are unaware of any porcine-derived bone graft products currently used in orthopaedic surgery practice. Results from the current study suggest that porcine-derived bone scaffolds warrant further consideration to serve as a potential bone graft substitute.

Nutritional markers may identify patients with greater risk of re-admission after geriatric hip fractures

Metastasis is the leading cause of cancer-related death and drives patient morbidity as well as healthcare costs. Bone is the primary site of metastasis for several cancers—breast and prostate cancers in particular. Efforts to treat bone metastases have been stymied by a lack of models to study the progression, cellular players, and signaling pathways driving bone metastasis. In this review, we examine newly described and classic models of bone metastasis. Through the use of current in vivo, microfluidic, and in silico computational bone metastasis models we may eventually understand how cells escape the primary tumor and how these circulating tumor cells then home to and colonize the bone marrow. Further, future models may uncover how cells enter and then escape dormancy to develop into overt metastases. Recreating the metastatic process will lead to the discovery of therapeutic targets for disrupting and treating bone metastasis.

Basic Shoulder Arthroscopy: Lateral Decubitus Patient Positioning

The article entitled “Determination of the accuracy of navigated kinematic unicompartmental knee arthroplasty: a 2-year follow-up” (1) published in the Journal of Arthroplasty was reviewed in detail. We would like to commend the authors on taking on such an important topic. This investigation retrospectively reviewed prospective data collected over a 4-year period on consecutive patients that underwent minimally invasive unicompartmental knee arthroplasty (UKA) with the Stryker (Mahwah, NJ, USA) Triathlon partial knee arthroplasty (PKA) prosthesis with the use of the Stryker precision computer navigation (PCN) system.