Three-dimensional printing in surgery: a review of current surgical applications.

BACKGROUND: Three-dimensional printing (3DP) is gaining increasing recognition as a technique that will transform the landscape of surgical practice. It allows for the rapid conversion of anatomic images into physical objects, which are being used across a variety of surgical specialties. It has been unclear which groups are leading the way in coming up with novel ways of using the technology and what specifically the technology is being used for. The aim of this article was to review the current applications of 3DP in modern surgical practice. MATERIALS AND METHODS: An electronic search was carried out in MEDLINE, EMBASE, and PsycINFO for terms related to 3DP. These were then screened for relevance and practical applications of the technology in surgery. RESULTS: Four hundred eighty-eight articles were initially found, and these were eventually narrowed down to 93 full-text articles. It was determined that there were three main areas in which the technology is being used to print: (1) anatomic models, (2) surgical instruments, and (3) implants and prostheses. CONCLUSIONS: Different specialties are at different stages in the use of the technology. The costs involved with implementing the technology and time taken for printing are important factors to consider before widespread use. For the foreseeable future, this is an exciting and interesting technology with the capacity to radically change health care and revolutionize modern surgery.

Why Mechanism Matters: A Literature Review of Simultaneous Ipsilateral Tibial Tuberosity Avulsion and Patella Fracture With Case Report.

Simultaneous ipsilateral tibial tuberosity avulsion and patella fractures are rare in adults. They are often associated with patients who have underlying bone disease and other medical co-morbidities. Here we describe a case where this injury was attributed to direct trauma and demonstrate our department's management for such an injury. In addition to our case report, we have performed a systematic literature review to identify other cases of the same injury. Only four other cases have been reported. Here we summarise and compare the management and outcome measures reported in each case. All patients are managed differently, yet all authors report satisfactory outcomes. With this being a relatively rare injury, further research is required to establish a gold standard for management of such patients.

Femoral fracture type can be predicted from femoral structure: A finite element study validated by digital volume correlation experiments.

Proximal femoral fractures can be categorized into two main types: Neck and intertrochanteric fractures accounting for 53% and 43% of all proximal femoral fractures, respectively. The possibility to predict the type of fracture a specific patient is predisposed to would allow drug and exercise therapies, hip protector design, and prophylactic surgery to be better targeted for this patient rendering fracture preventing strategies more effective. This study hypothesized that the type of fracture is closely related to the patient-specific femoral structure and predictable by finite element (FE) methods. Fourteen femora were DXA scanned, CT scanned, and mechanically tested to fracture. FE-predicted fracture patterns were compared to experimentally observed fracture patterns. Measurements of strain patterns to explain neck and intertrochanteric fracture patterns were performed using a digital volume correlation (DVC) technique and compared to FE-predicted strains and experimentally observed fracture patterns. Although loaded identically, the femora exhibited different fracture types (six neck and eight intertrochanteric fractures). CT-based FE models matched the experimental observations well (86%) demonstrating that the fracture type can be predicted. DVC-measured and FE-predicted strains showed obvious consistency. Neither DXA-based BMD nor any morphologic characteristics such as neck diameter, femoral neck length, or neck shaft angle were associated with fracture type. In conclusion, patient-specific femoral structure correlates with fracture type and FE analyses were able to predict these fracture types. Also, the demonstration of FE and DVC as metrics of the strains in bones may be of substantial clinical value, informing treatment strategies and device selection and design. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:993-1001, 2018.

Service contribution and cost-effectiveness of specialist registrars in NHS trusts: a survey and costing analysis.

Since the introduction of the European Working Time Directive, specialist registrars arguably contribute less to clinical service. The purpose of this study was to broadly quantify the service contribution of specialist registrars across a range of specialties and their value to an NHS organisation. A questionnaire-based survey of the clinical activities of specialist registrars in a large NHS trust was undertaken. Simple costing analyses of this -clinical activity were performed. Responses from 66 specialist registrars in 24 specialties showed an average of 51% overall clinical autonomy. Trainees attended an average of 2.7 outpatient clinics per week and spent 3.5 sessions a week doing ward work. Medical trainees took more referrals and attended more clinics. An analysis of costings suggested that surgical trainees might have generated around £700,000 income per year for the trust. Overall, specialist registrars make a substantial contribution to NHS clinical service and are cost-effective.

Mutations in the reverse transcriptase component of telomerase (TERT) in patients with bone marrow failure.

Human telomerase has two core components, the RNA molecule (TERC) that provides the template for telomere repeat elongation and a reverse transcriptase (TERT) that is responsible for the addition of telomere repeats at the ends of each chromosome. Mutations in TERC have been found in the autosomal-dominant form of the inherited bone marrow failure syndrome dyskeratosis congenita and in a subset of patients with aplastic anemia and myelodysplasia. These patients have short telomeres compared to age-matched controls. These observations suggest that uncharacterised cases of dyskeratosis congenita/aplastic anemia may have mutations in TERT or other molecules that associate with TERC in the telomerase complex. We have therefore screened the TERT gene for mutation by denaturing HPLC in 80 patients with inherited and acquired bone marrow failure (24 with dyskeratosis congenita, 36 with constitutional aplastic anemia, 13 with idiopathic aplastic anemia and 7 with other forms of bone marrow failure). 15 different TERT mutations have been identified. Of these, 5 are in flanking intron sequences, 6 are synonymous and 4 are non-synonymous (missense) substitutions in the coding sequence. These are the first natural mutations of TERT to be described and we highlight their possible pathogenic role in the development of bone marrow failure.