Removing the barriers to prehospital blood: A roadmap to success.

ABSTRACT: This review describes the necessity, evolution, and current state of prehospital blood programs in the United States. Less than 1% of 9-1-1 ground emergency medical service agencies have been able to successfully implement prehospital blood transfusions as part of a resuscitation strategy for patients in hemorrhagic shock despite estimates that annually between 54,000 and 900,000 patients may benefit from its use. The use of prehospital blood transfusions as a tool for managing hemorrhagic shock has barriers to overcome to ensure it becomes widely available to patients throughout the United States. Barriers include (1) current state Emergency Medical Services clinicians' scope of practice limitations; (2) program costs and reimbursement of blood products; (3) no centralized data collection process for prehospital hemorrhagic shock and patient outcomes; (4) collaboration between prehospital agencies, blood suppliers, and hospital clinicians and transfusion service activities. The following article identifies barriers and a proposed roadmap to reduce death due to prehospital hemorrhage.

Scalable manufacture of therapeutic mesenchymal stromal cell products on customizable microcarriers in vertical wheel bioreactors that improve direct visualization, product harvest, and cost.

BACKGROUND AIMS: Human mesenchymal stromal cells (hMSCs) and their secreted products show great promise for treatment of musculoskeletal injury and inflammatory or immune diseases. However, the path to clinical utilization is hampered by donor-tissue variation and the inability to manufacture clinically relevant yields of cells or their products in a cost-effective manner. Previously we described a method to produce chemically and mechanically customizable gelatin methacryloyl (GelMA) microcarriers for culture of hMSCs. Herein, we demonstrate scalable GelMA microcarrier-mediated expansion of induced pluripotent stem cell (iPSC)-derived hMSCs (ihMSCs) in 500 mL and 3L vertical wheel bioreactors, offering several advantages over conventional microcarrier and monolayer-based expansion strategies. METHODS: Human mesenchymal stromal cells derived from induced pluripotent cells were cultured on custom-made spherical gelatin methacryloyl microcarriers in single-use vertical wheel bioreactors (PBS Biotech). Cell-laden microcarriers were visualized using confocal microscopy and elastic light scattering methodologies. Cells were assayed for viability and differentiation potential in vitro by standard methods. Osteogenic cell matrix derived from cells was tested in vitro for osteogenic healing using a rodent calvarial defect assay. Immune modulation was assayed with an in vivo peritonitis model using Zymozan A. RESULTS: The optical properties of GelMA microcarriers permit noninvasive visualization of cells with elastic light scattering modalities, and harvest of product is streamlined by microcarrier digestion. At volumes above 500 mL, the process is significantly more cost-effective than monolayer culture. Osteogenic cell matrix derived from ihMSCs expanded on GelMA microcarriers exhibited enhanced in vivo bone regenerative capacity when compared to bone morphogenic protein 2, and the ihMSCs exhibited superior immunosuppressive properties in vivo when compared to monolayer-generated ihMSCs. CONCLUSIONS: These results indicate that the cell expansion strategy described here represents a superior approach for efficient generation, monitoring and harvest of therapeutic MSCs and their products.

TWIST1 and TSG6 are coordinately regulated and function as potency biomarkers in human MSCs.

Mesenchymal stem/stromal cells (MSCs) have been evaluated in >1500 clinical trials, but outcomes remain suboptimal because of knowledge gaps in quality attributes that confer potency. We show that TWIST1 directly represses TSG6 expression that TWIST1 and TSG6 are inversely correlated across bone marrow-derived MSC (BM-MSC) donor cohorts and predict interdonor differences in their proangiogenic, anti-inflammatory, and immune suppressive activity in vitro and in sterile inflammation and autoimmune type 1 diabetes preclinical models. Transcript profiling of TWIST1HiTSG6Low versus TWISTLowTSG6Hi BM-MSCs revealed previously unidentified roles for TWIST1/TSG6 in regulating cellular oxidative stress and TGF-ß2 in modulating TSG6 expression and anti-inflammatory activity. TWIST1 and TSG6 levels also correlate to donor stature and predict differences in iPSC-derived MSC quality attributes. These results validate TWIST1 and TSG6 as biomarkers that predict interdonor differences in potency across laboratories and assay platforms, thereby providing a means to manufacture MSC products tailored to specific diseases.

Morpholino-driven blockade of Dkk-1 in osteosarcoma inhibits bone damage and tumour expansion by multiple mechanisms.

BACKGROUND: Osteosarcoma (OS) is the most common primary bone malignancy. Chemotherapy plays an essential role in OS treatment, potentially doubling 5-year event-free survival if tumour necrosis can be stimulated. The canonical Wnt inhibitor Dickkopf-1 (Dkk-1) enhances OS survival in part through upregulation of aldehyde-dehydrogenase-1A1 which neutralises reactive oxygen species originating from nutritional stress and chemotherapeutic challenge. METHODS: A vivo morpholino (DkkMo) was employed to block the expression of Dkk-1 in OS cells. Cell mitosis, gene expression and bone destruction were measured in vitro and in vivo in the presence and absence of doxorubicin (DRB). RESULTS: DkkMo reduced the expression of Dkk-1 and Aldh1a1, reduced expansion of OS tumours, preserved bone volume and architecture and stimulated tumour necrosis. This was observed in the presence or absence of DRB. CONCLUSION: These results indicate that administration of DkkMo with or without chemotherapeutics can substantially improve OS outcome with respect to tumour expansion and osteolytic corruption of bone in experimental OS model.

A scalable system for generation of mesenchymal stem cells derived from induced pluripotent cells employing bioreactors and degradable microcarriers.

Human mesenchymal stem cells (hMSCs) are effective in treating disorders resulting from an inflammatory or heightened immune response. The hMSCs derived from induced pluripotent stem cells (ihMSCs) share the characteristics of tissue derived hMSCs but lack challenges associated with limited tissue sources and donor variation. To meet the expected future demand for ihMSCs, there is a need to develop scalable methods for their production at clinical yields while retaining immunomodulatory efficacy. Herein, we describe a platform for the scalable expansion and rapid harvest of ihMSCs with robust immunomodulatory activity using degradable gelatin methacryloyl (GelMA) microcarriers. GelMA microcarriers were rapidly and reproducibly fabricated using a custom microfluidic step emulsification device at relatively low cost. Using vertical wheel bioreactors, 8.8 to 16.3-fold expansion of ihMSCs was achieved over 8 days. Complete recovery by 5-minute digestion of the microcarriers with standard cell dissociation reagents resulted in >95% viability. The ihMSCs matched or exceeded immunomodulatory potential in vitro when compared with ihMSCs expanded on monolayers. This is the first description of a robust, scalable, and cost-effective method for generation of immunomodulatory ihMSCs, representing a significant contribution to their translational potential.

Characterization of a pluripotent stem cell-derived matrix with powerful osteoregenerative capabilities.

Approximately 10% of fractures will not heal without intervention. Current treatments can be marginally effective, costly, and some have adverse effects. A safe and manufacturable mimic of anabolic bone is the primary goal of bone engineering, but achieving this is challenging. Mesenchymal stem cells (MSCs), are excellent candidates for engineering bone, but lack reproducibility due to donor source and culture methodology. The need for a bioactive attachment substrate also hinders progress. Herein, we describe a highly osteogenic MSC line generated from induced pluripotent stem cells that generates high yields of an osteogenic cell-matrix (ihOCM) in vitro. In mice, the intrinsic osteogenic activity of ihOCM surpasses bone morphogenic protein 2 (BMP2) driving healing of calvarial defects in 4 weeks by a mechanism mediated in part by collagen VI and XII. We propose that ihOCM may represent an effective replacement for autograft and BMP products used commonly in bone tissue engineering.

Patient-Reported Outcomes After Structural Autograft for Large or Cystic Talar Dome Osteochondral Lesions.

BACKGROUND: While smaller talar dome osteochondral lesions (OCLs) are successfully treated with bone marrow stimulation techniques, the optimal treatment for large or cystic OCLs remains controversial. This study tested the hypothesis that transferring structural autograft bone from the distal tibia to the talus for large or cystic OCLs improves pain and function. METHODS: Thirty-two patients with large or cystic OCLs underwent structural bone grafting from the ipsilateral distal tibia to the talar dome. Patients were assessed with subjective patient-centered tools and objective clinical outcomes. Average age was 48.6 ± 14.9 years, and average follow-up was 19.5 ± 13.3 months. Average lesion area was 86.2 ± 23.5 mm2, and average depth was 8.4 ± 3.0mm. RESULTS: At final follow-up, improvement compared to preoperative scores was seen in American Orthopaedic Foot & Ankle Society (65.4 ± 21.2 to 86.9 ± 15.0, P < .05), Foot Function Index (48.9 ± 20.8 to 21.1 ± 18.9, P < .05), visual analog scale for pain (4.7 ± 3.0 to 1.4 ± 1.5, P < .05), and Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (40.4 ± 5.4 to 45.5 ± 7.4, P < .05) scores. There was no improvement in PROMIS pain interference (54.7 ± 18.1 to 52.4 ± 7.3, P > .05). Satisfaction with surgery was 8.4 ± 1.3/10, and 96% of patients would have the procedure again. Ninety-four percent of patients returned to work and/or play. One patient had a deep vein thrombosis 6 weeks postoperatively, and 1 patient underwent ankle fusion at 18 months postoperatively. CONCLUSION: This study demonstrates that structural bone graft harvested from the distal tibia transferred to the talus was a safe and effective treatment for large and cystic OCLs. Outcomes compare favorably to other described techniques for treatment of these injuries. LEVEL OF EVIDENCE: Level IV, case series.

Natural History of Avascular Necrosis in the Talus: When to Operate.

Avascular necrosis (AVN) of the talus bone is a progressive and debilitating consequence of trauma or exposure to a variety of risk factors. The Ficat classification describes current understanding of the natural history of AVN, including preclinical, preradiographic, precollapse, postcollapse, and arthritic stages. The size and location of the avascular region likely determines risk of progression; however, symptoms do not correlate with stage. Patients may be minimally symptomatic despite diffuse involvement for long periods. Joint-sparing strategies have shown promise but do not universally prevent progression of the disease. When bone structure fails, joint-sacrificing strategies may be required.

Implementation of Patient-Reported Outcomes Measurement Information System Data Collection in a Private Orthopedic Surgery Practice.

BACKGROUND: The authors describe a method of collecting patient-reported outcomes (PROs) using computerized adaptive tests (CATs) in a high-volume orthopedic surgery practice with limited resources and no research coordinator. METHODS: Patient-Reported Outcomes Measurement Information System CATs were collected prospectively for all clinic patients using a tablet and recorded in the electronic medical record. Scores were compared with validated national norms using single-variable t tests. Linear regression was used to assess age effects. Preoperative and postoperative pain scales were compared using paired t tests. RESULTS: In total, 4,524 CATs were administered during 10,719 visits (42%), reaching 70% as more tablets were introduced. Completing the CATs required 157 seconds. Older patients took more time than younger ones ( P < .05). Compared with normalized t scores of 50 ± 10 for the US population, pain intensity was 48.0 (95% confidence interval [CI], 47.8-48.2), pain interference 58.9 (95% CI, 58.6-59.1), physical function 40.1 (95% CI, 39.9-40.3), global physical health 43.4 (95% CI, 41.9-44.9), and global mental health 41.1 (95% CI, 40.89-41.4) ( P < .05 for all). Age had a small effect on all domains ( P < .05). Approximately 20 patients would be required to demonstrate a 15% change for a 2-tailed, paired study with α = 0.05 and 80% power. After surgery, pain intensity improved from 51.9 ± 8.2 to 44.1 ± 8.5, pain interference improved from 62.5 ± 6.9 to 55.7 ± 8.4, and physical function improved from 37.3 ± 8.9 to 41.5 ± 7.9 ( P < .05 for all). CONCLUSIONS: Using tablets to administer CATs and entering the data in the electronic medical record for later retrieval was an effective technique to collect PROs. An adequate number of tablets are needed for acceptable completion rates. Modest sample size requirements for comparative studies highlight the potential of these tools and techniques. LEVEL OF EVIDENCE: Level II, Prospective Comparative Study.

Fixation of osteoporotic distal fibula fractures: A biomechanical comparison of locking versus conventional plates.

The increased use of locking plates to treat difficult fracture scenarios has been advocated in patients that have reduced bone mineral density. One of these difficult fracture patterns, fixation of the distal fragment of a distal fibula fracture, may depend on unicortical and cancellous bony purchase. This study investigated the construct stiffness afforded by using locking and conventional plating schema in a cadaveric model. Overall, the data indicate that a locking plate construct with two distal unicortical screws was mechanically equivalent to standard plating with 3 distal screws. In addition, fixation with the standard plates was dependent on bone mineral density (BMD) whereas the locking plate fixation was independent of BMD. The clinical implication of this study is that locking plates may be advantageous in patients with the most severe osteoporosis.

Subtalar joint arthrodesis using a single lag screw.

BACKGROUND: This study tested the hypotheses that fusing the subtalar joint with a single lag screw from the posteroinferior calcaneus to the anterior talar neck is an effective technique and that factors affecting the time to fusion can be identified. METHODS: Between October, 1995, and July, 2002, the senior author (RAM) performed 101 isolated subtalar arthrodeses using a technique of single lag-screw fixation from posteroinferior to anterosuperior across the posterior facet of the subtalar joint combined with the application of an autograft taken from the floor of the sinus tarsi and anterior process. The average patient age was 52 (range 17 to 82) years. There were 52 women (53 arthrodeses) and 48 men (48 arthrodeses). Eight of 101 (8%) arthrodeses were revisions. The indications included posttraumatic arthritis (45), posterior tibial tendon dysfunction (18), failed prior ankle joint fusion (14), idiopathic disorders (12), hindfoot coalition (7), rheumatoid arthritis (3), and Charcot-Marie-Tooth disease (2). Fifteen of 101 patients (15%) smoked an average of 0.9 +/- 0.5 pack of cigarettes per day. RESULTS: Two of 101 joints did not fuse, resulting in an overall fusion rate of 98%. The average time to fusion was 12.3 +/- 3.4 weeks. The presence of a prior ankle fusion significantly prolonged the time to fusion of the subtalar joint (11.9 +/- 2.3 vs. 14.9 +/- 7.0, p = .003). Other factors, including smoking, revision surgery, patient age, and patient sex, did not affect time to fusion. The fixation screw was removed in 13 of 101 (13%) joints at an average of 8.8 +/- 0.5 months. CONCLUSIONS: Using a single 7.0-mm lag screw across the posterior facet of the subtalar joint results in fusion of the subtalar joint in 98% of patients. A prior ankle arthrodesis delays the time to fusion of the subtalar joint by 3 weeks. This is a simple and reliable technique for achieving fusion of the subtalar joint.

Metachronous multicentric giant cell tumor: a case report and literature review.

Metachronous multicentric giant cell tumors of bone are rare. The case of a 47-year-old woman who had a giant cell tumor of the ilium develop 24 years after resection of a giant cell tumor of the proximal tibia is reported. The initial and current surgical approaches for this patient are described. A literature review is presented to show that this patient had the longest disease-free interval documented for a patient with metachronous multicentric giant cell tumors.

The University of California at San Francisco international orthopaedic elective.

International volunteerism helps remedy global inequities in orthopaedic care and provides relief for increasing professional disillusionment experienced by many orthopaedic surgeons in the United States. From 1992 to 1998, 41% of residents from the Department of Orthopaedic Surgery at the University of California, San Francisco volunteered overseas. Approximately one half of those have continued volunteering internationally after residency, including many who led later trips with residents. Based on the success of these trips, the University of California, San Francisco Department of Orthopaedic Surgery established a 1-month elective rotation in Umtata, South Africa in conjunction with Orthopaedics Overseas. Seventy-six percent of residents have chosen this opportunity since the program's inception in 1998. The University of California, San Francisco experience suggests that early exposure to international volunteerism during residency promotes continued participation in volunteer activities after graduation. By providing residents with the opportunity to volunteer overseas, the University of California, San Francisco hopes to enhance resident education, foster a lifelong spirit of volunteerism, and serve as a model for other orthopaedic training programs.