Summary Multiple myeloma (MM) is characterized by almost exclusive tropism of malignant cells for the bone marrow (BM) milieu. The survival and proliferation of malignant plasma cells have been shown to rely on interactions with nonmalignant stromal cells, in particular mesenchymal stromal cells (MSCs), in the BM microenvironment. However, the BM microenvironment is composed of a diverse array of cell types. This study examined the role of macrophages, an abundant component of BM stroma, as a potential niche component that supports malignant plasma cells. We investigated the proliferation of MM tumour cell lines when cultured alone or together with MSCs, macrophages, or a combination of MSCs and macrophages, using the carboxyfluorescein succinimidyl ester assay. Consistently, we observed increased proliferation of MM cell lines in the presence of either MSCs or macrophages compared to cell line-only control. Furthermore, the combined co-culture of MSCs plus macrophages induced the greatest degree of proliferation of myeloma cells. In addition to increased proliferation, MSCs and macrophages decreased the rate of apoptosis of myeloma cells. Our in vitro studies provide evidence that highlights the role of macrophages as a key component of the BM microenvironment facilitating the growth of malignant plasma cells in MM.

Large-sized cranial defects can arise from many etiologies, including open skull trauma, infection, tumor, and craniofacial reconstruction complications. With advances in neurotrauma care and early surgical decompression, trauma outcomes have improved over time; survivors are left with cranial defects. While large retrospective studies and metaanalyses of adult cranioplasty have been conducted, less is known about outcomes in the pediatric population.Reimplantation of the autologous bone flaps in children is thought to be advantageous. The osseous material can become reincorporated over the process of a child's maturation and growth. However, bone resorption is seen in up to 50% in the pediatric population 1,2 compared with up to 6.5% in adults, 3 necessitating further reconstructive surgery either with further autologous materials (split-thickness cranial bone graft, particulate bone graft with or without resorbable mesh), or other alloplastic materials (methyl methacrylate, hydroxyapatite cement, demineralized bone, and titanium mesh). We review the literature on special considerations, materials, and outcomes of large-sized cranioplasty in children such as after decompressive craniectomy (►Table 1). Autologous ReconstructionAutologous cranioplasty after decompressive craniectomy is considered the gold standard in pediatric care because of the ability of the bone graft to reincorporate into the skull (osseointegration), lower risk of material rejection, and ability to allow growth of the skull. There are several approaches to this form of reconstruction (►Table 2). The three main ways to perform an autologous cranioplasty use bone stored in the body, cryopreserved bone, or bone flaps harvested from a donor site. With pediatric patients, additional considerations must account for the high incidence of bone resorption (►Fig. 1a-c), the immature osseous skeleton, and future growth. Bone Flap Storage MethodsMethods of bone preservation each have advantages and drawbacks. Cryopreservation of the bone flap obviates a second surgical site and is favored by most of the U.S. centers. However, cryopreservation requires facilities for bone storage; in cases of geographic transfer of patient care, logistics of transport pose additional difficulty.4 In addition, the freezing process can devitalize the bone and result in an increased rate of complications including infection, resorption, and cosmetic deformity. AbstractLarge-sized calvarial defects in pediatric patients pose a reconstructive challenge because of children's unique physiology, developing anatomy, and dynamic growth. We review the current literature and outcomes with autologous and alloplastic cranioplasty in the pediatric population.

BackgroundThe demand for total hip and total knee arthroplasty in the USA is projected to increase significantly. Traditionally, face-to-face physical therapy has been an essential component of recovery in patients after total joint arthroplasty. Emerging technology allows telerehabilitation, or virtual physical therapy, which may reduce costs and increase standardization, but its effects on outcomes are not known.Questions/PurposeWe sought to review our initial experience using a telerehabilitation protocol for patients after primary total hip or total knee arthroplasty.MethodsIn this pilot study, we retrospectively compared our first 40 telerehabilitation patients after a primary total hip or knee arthroplasty with a historical cohort or literature referenced values and evaluated (1) readmission rates at 90 days, (2) emergency department visits, (3) patient-reported outcome scores, (4) incidence of closed knee manipulation within 90 days of primary total knee arthroplasty, and (5) patient satisfaction surveys.ResultsWe observed no increase in the telerehabilitation group at 90 days in readmissions, emergency department visits, or closed knee manipulations. Accuracy of telerehabilitation exercises performed was 92%. Patient-reported outcome scores showed improvements comparable with traditional therapy. Extremely high patient satisfaction scores were reported with the telerehabilitation protocol.ConclusionOur early experience demonstrates the feasibility of implementing a telerehabilitation program following primary total hip or knee arthroplasty without compromising clinical quality and with high patient satisfaction.Electronic supplementary materialThe online version of this article (10.1007/s11420-019-09715-w) contains supplementary material, which is available to authorized users.

Increased CP caused an observable decrease in PmO2 that was reversed by fasciotomy. PmO2 can be directly measured in real time with a polarographic tissue pO2 probe. This study is the first step of evaluating an alternative method for diagnosing acute CS.

The transverse acetabular ligament (TAL) is a reliable native anatomic landmark that can be used to guide accurate acetabular implant positioning during total hip arthroplasty through the direct anterior approach. The accurate acetabular implant position is defined by the preoperative plan, which corresponds to the Lewinnek safe zone. This article describes the anatomy of the TAL , exposure of the TAL, and pearls and pitfalls for exposure of the acetabulum during total hip arthroplasty through the direct anterior approach. This article discusses how the TAL is used to guide acetabular implant positioning and describes pilot data from our single surgeon case series (n = 31). Patient EvaluationThe preoperative imaging workup includes AP standing and cross-table lateral radiographs of the hip. All patients with primary total hip arthroplasty (THA) are indicated for this technique. Identifying the transverse acetabular ligament (TAL) is challenging in cases of hypertrophic osteoarthritis; it can often be identified after osteophytes are taken down.