The impact of a hands-on arthrocentesis workshop in undergraduate medical education.

BACKGROUND: To evaluate the impact of a training programme for arthrocentesis on procedural skills enhancement and self-confidence in medical students. METHODS: Participants were provided a structured workshop on injection models. A self-confidence questionnaire and medical knowledge assessment were performed. Retention of knowledge and skills were assessed at a later time point during a formal OSCE examination and compared to participants who had not attended a lecture and clinical attachments only. P-values, 95% confidence intervals about the mean, standard error of the mean, and standard deviations of the differences were calculated. RESULTS: All participants gained self-confidence, and improvement of their skills was significant. The mean self-confidence with performing an arthrocentesis procedure increased from 1.3 pre- to 5.9 points post-workshop (10-point Likert scale). The knee was the joint students felt most confident with (1.3 to 6.5 points). Knowledge on the selection of corticosteroid preparations (1.2 to 5.8 points) gained substantially, as well as confidence in providing post-injection advice (1.9 to 6.6 points). Upon the OSCE examination, attendance to the workshop resulted in a significant higher total score (16.2 vs 14.8 points, p < 0.05). CONCLUSIONS: A workshop for arthrocentesis procedures, in conjunction with other learning activities, is well suited to increasing skills and self-confidence in fourth year medical students and allows for developing important baseline knowledge and practicing invasive techniques without risk to a patient. TRIAL REGISTRATION: This trial has been approved by the human research ethics committee of the University of Adelaide (Ethics approval No H-2019-134).

Vancouver B2 Peri-Prosthetic Fractures in Cemented Femoral Implants can be Treated With Open Reduction and Internal Fixation Alone Without Revision.

BACKGROUND: The aim of this study is to assess the outcomes of 52 consecutive Vancouver B2 peri-prosthetic fractures around cemented polished double-tapered stems treated by open reduction and internal fixation in 2 trauma centers in 2 countries. METHODS: Outcomes included modified Harris Hip Score (mHHS), Harris Pain Score, and return to pre-injury mobility. Fracture healing was assessed; implant subsidence measured and complications including re-operations reported. RESULTS: No patient was lost to follow-up. Median patient age at operation was 82 years (range 43-98); Harris pain scores showed minimal pain (median 42, range 10-44) at latest follow-up. Median total subsidence at 1 year was 1.1 mm (range 0-5.4), the majority of which occurred within the cement mantle. No subsequent femoral stem revision was required (median 2.9 years, 0-10); however, there were 3 re-operations: 1 re-operation for pre-existing recurrent dislocation involving head liner exchange and 2 for repeat fixation due to metal fatigue. Two additional fractures occurred below the new plating, requiring further plating whilst still retaining the original stems. CONCLUSION: Anatomical reduction and open reduction and internal fixation of Vancouver B2 peri-prosthetic fractures should be considered as an appropriate treatment solution for frail elderly patients with a peri-prosthetic fracture around cemented polished double-tapered stems.

Unbiased gene expression analysis of the delayed fracture healing observed in Zucker diabetic fatty rats.

Aims: Impaired fracture repair in patients with type 2 diabetes mellitus (T2DM) is not fully understood. In this study, we aimed to characterize the local changes in gene expression (GE) associated with diabetic fracture. We used an unbiased approach to compare GE in the fracture callus of Zucker diabetic fatty (ZDF) rats relative to wild-type (WT) littermates at three weeks following femoral osteotomy. Methods: Zucker rats, WT and homozygous for leptin receptor mutation (ZDF), were fed a moderately high-fat diet to induce T2DM only in the ZDF animals. At ten weeks of age, open femoral fractures were simulated using a unilateral osteotomy stabilized with an external fixator. At three weeks post-surgery, the fractured femur from each animal was retrieved for analysis. Callus formation and the extent of healing were assessed by radiograph and histology. Bone tissue was processed for total RNA extraction and messenger RNA (mRNA) sequencing (mRNA-Seq). Results: Radiographs and histology demonstrated impaired fracture healing in ZDF rats with incomplete bony bridge formation and an influx of intramedullary inflammatory tissue. In comparison, near-complete bridging between cortices was observed in Sham WT animals. Of 13,160 genes, mRNA-Seq analysis identified 13 that were differentially expressed in ZDF rat callus, using a false discovery rate (FDR) threshold of 10%. Seven genes were upregulated with high confidence (FDR = 0.05) in ZDF fracture callus, most with known roles in inflammation. Conclusion: These findings suggest that elevated or prolonged inflammation contributes to delayed fracture healing in T2DM. The identified genes may be used as biomarkers to monitor and treat delayed fracture healing in diabetic patients.

Does Time to Theatre Affect the Ability to Achieve Fracture Reduction in Tibial Plateau Fractures?

Surgical management of displaced tibial plateau fracture (TPF) is often delayed due to accompanying soft tissue injuries sustained at the time of injury. The primary aim of this study was to assess the effect of time to surgery on fracture reduction in cases of TPF. The secondary aim was to assess the effect of preoperative demographics and residual articular step on Lysholm Scores and Knee Injury and Osteoarthritis Outcome Scores (KOOS) following fixation. Patients between 2006 and 2017, managed by a single surgeon, were prospectively enrolled in the study. Reduction of articular step, defined as <2 mm, was assessed by a single blinded examiner. A total of 117 patients were enrolled, 52 with Schatzker II, 4 with Schatzker IV, and 61 with Schatzker VI fractures. Patients were followed up to a mean of 3.9 years. Analysis showed that the ability to achieve fracture reduction was negatively influenced by time to theatre, with the odds of achieving reduction decreasing 17% with each subsequent day post injury (p = 0.002). Furthermore, an increased time to theatre was associated with a reduced Lysholm score at one year (p = 0.01). The ability to achieve fracture reduction did not influence PROMs within the study period. We conclude that delay in surgical fixation negatively affects fracture reduction in TPF and may delay recovery. However, residual articular step does not necessarily influence PROMs over the mid-term.

The compressive properties of bone cements containing large doses of antibiotics.

The addition of large amounts of antibiotics to bone cement provides a convenient local delivery, but may influence the compressive properties of the cement. Flucloxacillin and vancomycin were added to Simplex P (Stryker, Limerick, Ireland) and VersaBond (Smith & Nephew) cements. Tripling the antibiotic dose from 2 to 6 g had little effect on the static compressive properties 24 hours after curing. After 4 weeks in phosphate-buffered saline, there was marked decrease in properties with the addition of antibiotics. Compressive strength of cements with 6 g of antibiotic was reduced to near or below the ASTM and ISO minimum of 70 MPa after 4 weeks in phosphate-buffered saline. Microcomputer tomography revealed increased porosity and clumping of the radiopacifier with the addition of antibiotics.

Surgical Technique to Manage Periprosthetic Fractures of the Knee in Patients with Infected Leg Ulcers: A Report of Two Cases.

CASES: We describe 2 cases of nonagenarians with periprosthetic knee fractures that were not amenable to either standard internal fixation nor prosthesis revision because of infected leg ulcers in the same limb. The fractures were internally fixed by percutaneous insertion of medial and lateral plates that spanned the knee. Both patients returned to their baseline level of activity without developing surgical site infections. CONCLUSIONS: Percutaneous bridging plates that span the knee are a useful option for treating these difficult cases.

A Systematic Review of Patient-reported Outcome Measures Used in Circular Frame Fixation.

INTRODUCTION: Clinical studies in orthopedics are using patient-reported outcome measures (PROMs) increasingly. PROMs are often being designed for a specific disease or an area of the body with the aim of being patient centered. As yet, none exists specifically for treatment with circular ring external fixation devices. AIM: The purpose of this study is to provide a comprehensive systematic review of the published literature related to the use of PROMs in patients that underwent treatment with circular frames (Ilizarov or Hexapod Type Fixators). METHODS: An online literature search was conducted for English language articles using the Scopus. RESULTS: There were 534 published articles identified. After initial filtering for relevance and duplication, this figure reduced to 17, with no further articles identified through searching the bibliographies. Exclusion criteria removed two articles resulting in 15 articles included in the final review. Out of the 15 studies identified, a total of 10 different scoring measures where used. The majority of studies used a combination of joint/limb-specific and generic health PROMs with an average of 2.5 per study. No paper specifically discussed all eight PROMs criteria when justifying which PROMs they used. CONCLUSION: Our findings indicate that none of the PROMs analyzed in this systematic review are truly representative of the health outcomes specific to this patient group and, therefore, propose that a PROM specific to this patient group needs to be developed. HOW TO CITE THIS ARTICLE: Antonios T, Barker A, Ibrahim I, et al. A Systematic Review of Patient-reported Outcome Measures Used in Circular Frame Fixation. Strategies Trauma Limb Reconstr 2019;14(1):34-44.

Time dependent loss of trabecular bone in human tibial plateau fractures.

We investigated if time between injury and surgery affects cancellous bone properties in patients suffering tibial plateau fractures (TPF), in terms of structural integrity and gene expression controlling bone loss. A cohort of 29 TPF, operated 1-17 days post-injury, had biopsies from the fracture and an equivalent contralateral limb site, at surgery. Samples were assessed using micro-computed tomography and real-time RT-PCR analysis for the expression of genes known to be involved in bone remodeling and fracture healing. Significant decreases in the injured vs control side were observed for bone volume fraction (BV/TV, -13.5 ± 6.0%, p = 0.011), trabecular number (Tb.N, -10.5 ± 5.9%, p = 0.041) and trabecular thickness (Tb.Th, -4.6 ± 2.5%, p = 0.033). Changes in these parameters were more evident in patients operated 5-17 days post-injury, compared to those operated in the first 4 days post-injury. A significant negative association was found between Tb.Th (r = -0.54, p < 0.01) and BV/TV (r = -0.39, p < 0.05) in relation to time post-injury in the injured limb. Both BV/TV and Tb.Th were negatively associated with expression of key molecular markers of bone resorption, CTSK, ACP5, and the ratio of RANKL:OPG mRNA. These structure/gene expression relationships did not exist in the contralateral tibial plateau of these patients. This study demonstrated that there is a significant early time-dependent bone loss in the proximal tibia after TPF. This bone loss was significantly associated with altered expression of genes typically involved in the process of osteoclastic bone resorption but possibly also bone resorption by osteocytes. The mechanism of early bone loss in such fractures should be a subject of further investigation. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2865-2875, 2018.

Exposure of the superior gluteal neurovascular bundle for the safe application of acetabular reinforcement cages in complex revisions.

The posterior approach to the hip is the most common extensile approach used, however exposure is limited superiorly by the superior gluteal neurovascular bundle (SGNB). The extra-pelvic course of the SGNB demonstrates variability between individuals, occasionally located only 1 cm from the acetabular rim. In complex acetabular reconstructions where the application of a reinforcement cage maybe required protecting the SGNB is challenging. The flanges of these cages are designed to sit on the ilium superior to the acetabular rim and to receive screws for fixation. The application of such cages may result in iatrogenic injury to the SGNB by way of forceful retraction or entrapment. We describe a technique that involves exposure and release of the SGNB such that the flanges of cage constructs may be safely applied.

Effect of age and gender on cell proliferation and cell surface characterization of synovial fat pad derived mesenchymal stem cells.

Cell based therapies are being investigated for biological repair of a variety of disorders. Previous work has shown that mesenchymal stem cells (MSCs) from older patients have reduced proliferation rates. As age is associated with greater musculoskeletal morbidity, e.g., osteoarthritis, an optimal MSC expansion strategy is required for older patients. In this in vitro study we investigate how age and gender affect MSC proliferation rate and cell surface characterization, as well as identify a relationship between seeding density and proliferation that could be applied to therapeutic MSC uses. Synovial fat pad derived MSCs were isolated and expanded from 14 patients undergoing total knee replacements. The cells were seeded at densities between 50 and 10,000 cells/cm(2) and cell proliferation studies, flow cytometry, and cell surface staining were performed. Females were found to have consistently higher cell proliferation and cell surface marker expression. The cell surface marker CD105 had a constant expression irrespective of age. A statistically significant inverse relationship was found between seeding densities and cell proliferation rates. This study has shown that patient characteristics do effect cell proliferation rate and cell surface characterization, but as seeding density has a significant relationship with proliferation rate, it can be altered, possibly along with other cell culturing strategies, to compensate for the effects of patient factors on MSCs. We have also shown that gender affects cell proliferation and cell surface characterization, something most previous studies may have failed to identify as they group male and female patients together.

Dupuytren's Disease: Review of the Current Literature.

Dupuytren's disease is one of the most common condition seen by hand surgeons. It is not only prevalent but can also be a most debilitating condition resulting in significant loss of function of the fingers involved. The cause of this disease, however still remains largely unknown although some recent evidence suggests a stem cell etiology. This review article summarizes the current known knowledge of Dupuytren's as well as the clinical findings, investigations and treatments available.

Perioperative implications of surgery in elderly patients with hip fractures: an evidence-based review.

Hip fracture is a major cause of morbidity, mortality and loss of independence for the elderly. Surgical fixation of the fractured hip remains the standard of care to allow for early mobilisation and a return to independence. Operative management in this population carries its own set of problems. The altered physiological state of the older person, often coupled with significant comorbidity, can present challenges for the anaesthetist, the surgeon and the rest of the perioperative team. This article provides an evidence-based review of the important perioperative factors associated with hip fractures in the older person and their management.

Pore distribution and material properties of bone cement cured at different temperatures.

Implant heating has been advocated as a means to alter the porosity of the bone cement/implant interface; however, little is known about the influence on cement properties. This study investigates the mechanical properties and pore distribution of 10 commercially available cements cured in molds at 20, 37, 40 and 50 degrees Celsius. Although each cement reacted differently to the curing environments, the most prevalent trend was increased mechanical properties when cured at 50 degrees Celsius vs. room temperature. Pores were shown to gather near the surface of cooler molds and near the center in warmer molds for all cement brands. Pore size was also influenced. Small pores were more often present in cements cured at cooler temperatures, with higher-temperature molds producing more large pores. The mechanical properties of all cements were above the minimum regulatory standards. This work shows the influence of curing temperature on cement properties and porosity characteristics, and supports the practice of heating cemented implants to influence interfacial porosity.

Polymethylmethacrylate extrusion into the femoral nutrient vessel during arthroplasty: A phenomenon to be aware of.

Third generation cementing technique is now commonly used for total hip arthroplasty. The aim of this technique is to sufficiently pressurise the cement and allow maximal penetration of the cement into any remaining trabecular bone to provide a stable fixation of the prosthesis. We report a case where this pressurisation resulted in polymethylmethacrylate retrograde filling of the nutrient vessel and we discuss the controversial diagnosis and current literature surrounding this rare phenomenon.

Biomechanical influence of the vincula tendinum on digital motion after isolated flexor tendon injury: a cadaveric study.

PURPOSE: The vincula are specialized mesotendinous structures attaching to the flexor tendons of the hand. In addition to providing vascular supply to the tendons, the vincula can be mechanically important. The purpose of this study was to quantify the influence of intact vincula on digital flexion after flexor tendon laceration and to assess the ultimate strength and stiffness of the vincula. METHODS: The index, middle, and ring fingers of 12 fresh-frozen cadaveric fingers were dissected free at the level of the metacarpophalangeal joint, preserving at least 10 cm of the flexor and extensor tendons. A 9.8-N load was applied to each flexor tendon, and using digital photography and image analysis software, the degree of flexion at the proximal and distal interphalangeal joints and excursion of tendons proximal to the metacarpophalangeal joint was recorded before and after division of the flexor digitorum profundus and flexor digitorum superficialis tendons at their insertions. Load to failure and stiffness of the vincula were measured via a uniaxial material testing apparatus. Analysis of means was performed with a paired t-test. RESULTS: After division of the flexor digitorum superficialis tendon, proximal interphalangeal joint flexion secondary to the influence of the intact vincula was 93% of that compared with the uninjured digit. Distal interphalangeal joint flexion after flexor digitorum profundus transection was 69% of normal. The increased excursion of transected tendons compared with testing before division was 4 mm for flexor digitorum superficialis and 2 mm for flexor digitorum profundus. Load to failure was 27 N, and stiffness was 6 N/mm. CONCLUSIONS: The vincula breve can facilitate digital flexion after distal tendon transection, allowing tendons to act indirectly across the interphalangeal joints. The intact vincula breve can facilitate an almost normal range of motion across the interphalangeal joints, making the diagnosis of a flexor tendon injury difficult. In the immediate postinjury period, the vincula breve can hold a divided tendon within a few millimeters of its insertion. Testing against resistance is important to avoid missing the diagnosis of a tendon injury.