Variant Salter-Harris Type III Distal Ulna "T" Fracture in the Setting of Galeazzi Equivalent Wrist Injury: A Case Report.

CASE: An 11-year-old Caucasian boy presented to the emergency department with a displaced, closed, Galeazzi equivalent (GE) left wrist fracture sustained after a fall. Closed reduction was deemed unsatisfactory because of persistent displacement of the distal ulna epiphysis. An open reduction of the distal ulna and percutaneous fracture pinning was performed. At 1 year, the patient reported return to his preinjury baseline. No evidence of subsequent pathologic growth was detected on follow-up imaging. CONCLUSION: Open anatomic reduction of the distal ulna epiphysis and percutaneous fracture pinning may improve patient outcomes and limit progressive wrist deformity when treating GE wrist injuries.

Do 3-D Printed Handheld Models Improve Surgeon Reliability for Recognition of Intraarticular Distal Radius Fracture Characteristics?

BACKGROUND: For fracture care, radiographs and two-dimensional (2-D) and three-dimensional (3-D) CT are primarily used for preoperative planning and postoperative evaluation. Intraarticular distal radius fractures are technically challenging to treat, and meticulous preoperative planning is paramount to improve the patient's outcome. Three-dimensionally printed handheld models might improve the surgeon's interpretation of specific fracture characteristics and patterns preoperatively and could therefore be clinically valuable; however, the additional value of 3-D printed handheld models for fractures of the distal radius, a high-volume and commonly complex fracture due to its intraarticular configuration, has yet to be determined. QUESTIONS/PURPOSES: (1) Does the reliability of assessing specific fracture characteristics that guide surgical decision-making for distal radius fractures improve with 3-D printed handheld models? (2) Does surgeon agreement on the overall fracture classification improve with 3-D printed handheld models? (3) Does the surgeon's confidence improve when assessing the overall fracture configuration with an additional 3-D model? METHODS: We consecutively included 20 intraarticular distal radius fractures treated at a Level 1 trauma center between May 2018 and November 2018. Ten surgeons evaluated the presence or absence of specific fracture characteristics (volar rim fracture, die punch, volar lunate facet, dorsal comminution, step-off > 2 mm, and gap > 2 mm), fracture classification according to the AO/Orthopaedic Trauma Association (OTA) classification scheme, and their confidence in assessing the overall fracture according to the classification scheme, rated on a scale from 0 to 10 (0 = not at all confident to 10 = very confident). Of 10 participants regularly treating distal radius fractures, seven were orthopaedic trauma surgeons and three upper limb surgeons with experience levels ranging from 1 to 25 years after completion of residency training. Fractures were assessed twice, with 1 month between each assessment. Initially, fractures were assessed using radiographs and 2-D and 3-D CT images (conventional assessment); the second time, the evaluation was based on radiographs and 2-D and 3-D CT images with an additional 3-D handheld model (3-D printed handheld model assessment). On both occasions, fracture characteristics were evaluated upon a surgeon's own interpretation, without specific instruction before assessment. We provided a sheet demonstrating the AO/OTA classification scheme before evaluation on each session. Multi-rater Fleiss's kappa was used to determine intersurgeon reliability for assessing fracture characteristics and classification. Confidence regarding assessment of the overall fracture classification was assessed using a paired t-test. RESULTS: We found that 3-D printed models of intraarticular distal radius fractures led to no change in kappa values for the reliability of all characteristics: volar rim (conventional kappa 0.19 [95% CI 0.06 to 0.32], kappa for 3-D handheld model 0.23 [95% CI 0.11 to 0.36], difference of kappas 0.04 [95% CI -0.14 to 0.22]; p = 0.66), die punch (conventional kappa 0.38 [95% CI 0.15 to 0.61], kappa for 3-D handheld model 0.50 [95% CI 0.23 to 0.78], difference of kappas 0.12 [95% CI -0.23 to 0.47]; p = 0.52), volar lunate facet (conventional kappa 0.31 [95% CI 0.14 to 0.49], kappa for 3-D handheld model 0.48 [95% CI 0.23 to 0.72], difference of kappas 0.17 [95% CI -0.12 to 0.46]; p = 0.26), dorsal comminution (conventional kappa 0.36 [95% CI 0.13 to 0.58], kappa for 3-D handheld model 0.31 [95% CI 0.11 to 0.51], difference of kappas -0.05 [95% CI -0.34 to 0.24]; p = 0.74), step-off > 2 mm (conventional kappa 0.55 [95% CI 0.29 to 0.82], kappa for 3-D handheld model 0.58 [95% CI 0.31 to 0.85], difference of kappas 0.03 [95% CI -0.34 to 0.40]; p = 0.87), gap > 2 mm (conventional kappa 0.59 [95% CI 0.39 to 0.79], kappa for 3-D handheld model 0.69 [95% CI 0.50 to 0.89], difference of kappas 0.10 [95% CI -0.17 to 0.37]; p = 0.48). Although there appeared to be categorical improvement in kappa values for some fracture characteristics, overlapping CIs indicated no change. Fracture classification did not improve (conventional diagnostics: kappa 0.27 [95% CI 0.14 to 0.39], conventional diagnostics with an additional 3-D handheld model: kappa 0.25 [95% CI 0.15 to 0.35], difference of kappas: -0.02 [95% CI -0.18 to 0.14]; p = 0.81). There was no improvement in self-assessed confidence in terms of assessment of overall fracture configuration when a 3-D model was added to the evaluation process (conventional diagnostics 7.8 [SD 0.79 {95% CI 7.2 to 8.3}], 3-D handheld model 8.5 [SD 0.71 {95% CI 8.0 to 9.0}], difference of score: 0.7 [95% CI -1.69 to 0.16], p = 0.09). CONCLUSIONS: Intersurgeon reliability for evaluating the characteristics of and classifying intraarticular distal radius fractures did not improve with an additional 3-D model. Further studies should evaluate the added value of 3-D printed handheld models for teaching surgical residents and medical trainees to define the future role of 3-D printing in caring for fractures of the distal radius. LEVEL OF EVIDENCE: Level II, diagnostic study.

Nanoscale perfluorocarbon expediates bone fracture healing through selectively activating osteoblastic differentiation and functions.

BACKGROUND AND RATIONALE: Fracture incidence increases with ageing and other contingencies. However, the strategy of accelerating fracture repair in clinical therapeutics remain a huge challenge due to its complexity and a long-lasting period. The emergence of nano-based drug delivery systems provides a highly efficient, targeted and controllable drug release at the diseased site. Thus far, fairly limited studies have been carried out using nanomedicines for the bone repair applications. Perfluorocarbon (PFC), FDA-approved clinical drug, is received increasing attention in nanomedicine due to its favorable chemical and biologic inertness, great biocompatibility, high oxygen affinity and serum-resistant capability. In the premise, the purpose of the current study is to prepare nano-sized PFC materials and to evaluate their advisable effects on promoting bone fracture repair. RESULTS: Our data unveiled that nano-PFC significantly enhanced the fracture repair in the rabbit model with radial fractures, as evidenced by increased soft callus formation, collagen synthesis and accumulation of beneficial cytokines (e.g., vascular endothelial growth factor (VEGF), matrix metalloprotein 9 (MMP-9) and osteocalcin). Mechanistic studies unraveled that nano-PFC functioned to target osteoblasts by stimulating their differentiation and activities in bone formation, leading to accelerated bone remodeling in the fractured zones. Otherwise, osteoclasts were not affected upon nano-PFC treatment, ruling out the potential target of nano-PFC on osteoclasts and their progenitors. CONCLUSIONS: These results suggest that nano-PFC provides a potential perspective for selectively targeting osteoblast cell and facilitating callus generation. This study opens up a new avenue for nano-PFC as a promising agent in therapeutics to shorten healing time in treating bone fracture.

Analysis of fracture healing process by HR-pQCT in patients with distal radius fracture.

INTRODUCTION: High-resolution peripheral quantitative computed tomography (HR-pQCT) has enabled us to observe the changes in bone microarchitecture over time in vivo. In this study, the process of fracture healing was analyzed using HR-pQCT in patients with distal radius fracture who underwent osteosynthesis. MATERIALS AND METHODS: A total of 10 fracture sites identified from four patients with a distal radius fracture who underwent internal fixation with a volar locking plate (mean age 68.8 years, all women) were investigated. HR-pQCT was performed within a week (baseline) 4, 12, and 24 weeks after fracture. Rectangular region of interest (ROI) was established in the fracture site, inner callus, and external callus area, and the changes in bone mineral density (BMD) in each region were analyzed. RESULTS: From baseline to 24 weeks post-fracture, the BMD changed from 105.5 (95% CI 98.6-113) to 428.0 (331-554) mgHA/ccm at the fracture site, from 111.0 (104-119) to 375.3 (290-486) mgHA/ccm at the inner callus area, and from 98.5 (91.6-106) to 171.6 (132-222) mgHA/ccm at the external callus area. The BMD increased at the fracture site and inner callus area, but increased only slightly at the external callus area. At 24 weeks post-fracture, the BMD at the fracture site and inner callus area was significantly higher than the external callus area. CONCLUSION: In the healing process of postoperative distal radius fractures, increased BMD at the inner surface of the fracture site was confirmed in all fractures. Bone formation on the endosteal side may be a necessary condition for bone union of distal radius fractures.

Radial head fractures.

Radial head fractures are a common fracture involving the elbow joint. Patients typically present after a fall onto an outstretched hand with elbow pain and swelling. Without adequate treatment, this can lead to long-term complications, including loss of elbow motion and pain. Radial head fractures may also be associated with other injuries including elbow dislocation, neighbouring bony fractures and associated ligamentous rupture. It is therefore imperative that hospital clinicians understand the diagnosis and treatment of this condition. The plain radiograph is the optimum method to diagnose a radial head fracture. These fractures can be managed using a variety of techniques, from non-surgical conservative methods for the undisplaced fracture through to surgical fixation, radial head replacement and excision for the more complex, displaced fracture.

Proximal Radioulnar Translocation Associated with Posterior Fracture-Dislocation of Elbow in an Adolescent Girl: A Case Report.

CASE: A 14-year-old girl sustained a posterior elbow dislocation and presented with a proximal radioulnar translocation (PRUT) and a displaced fracture of the radial head. Reduction of the elbow dislocation and the proximal radioulnar translocation were achieved by external manipulation in the operating room. The radial head was not amenable to closed reduction and remained entrapped in the anteromedial compartment of the elbow. So open reduction and internal stabilization was carried out. CONCLUSIONS: In PRUT, closed reduction should be attempted. The radial head should be preserved even if it is fully dislocated from metaphysis. Retrograde intramedullary radial nailing provides enough stability of the fracture to promote early mobilization and facilitate union.

Evaluation of Hip Geometry Parameters in Patients With a Distal Radius Fracture.

BACKGROUND: Patients with a distal radius fracture (DRF) have an increased risk of subsequent fractures including hip fractures. The purpose of this study was to evaluate whether women with a DRF have certain hip geometry parameters known to indicate susceptibility to hip fractures. METHODS: We compared bone mineral density (BMD) and hip geometry parameters (hip axis length, neck shaft angle, mean cortical thickness, femur neck width, cross-sectional area [CSA], cross-sectional moment of inertia, section modulus, and buckling ratio) in 181 women with a DRF (DRF group) and 362 propensity score-matched women without a fracture (control group). We evaluated the associations between DRF and hip geometry parameters using logistic regression analysis. RESULTS: The DRF group had lower hip BMD; lower cortical thickness, CSA, and section modulus; and higher buckling ratio than the control group (all p < 0.05). The occurrence of a DRF was significantly associated with decreases in neck shaft angle (odds ratio [OR], 1.047; 95% confidence interval [CI], 1.008-1.088) and CSA (OR, 3.114; 95% CI, 1.820-5.326) after adjusting for age, BMI, and total hip BMD. CONCLUSIONS: In this study, women with a DRF were more likely than women without a DRF to have hip geometry parameters known to indicate susceptibility to hip fractures. Our results suggest that not only low hip BMD but also a decreased CSA could account for the increased risk of subsequent hip fracture in patients with a DRF.

Volar Locking Plate Fixation for Intra-Articular Distal Radius Fractures with Volar Lunate Facet Fragments Distal to the Watershed Line.

BACKGROUND: Standard volar plating of distal radius fractures may not adequately fix the volar lunate facet (VLF) fragment, which can result in volar carpal subluxation. We hypothesized that the size of VLF fragments distal to the watershed line might affect reduction loss after distally placed volar locking plate fixation for intra-articular distal radius fracture and examined if the presence of small displaced VLF fragments was a risk factor for reduction loss. METHODS: Twenty-seven hands of 27 patients with intra-articular distal radius fractures with VLF fragments distal to the watershed line were treated by using Acu-Loc 2 volar distal radius locking plate fixation. RESULTS: At final follow-up, the mean Mayo Performance Score was 90.9, and the mean Quick Disabilities of Arm, Shoulder, and Hand score was 13.6. On radiography, 5 patients had a reduction loss of >2 mm in ulnar variance from immediately postoperatively to final follow-up (group 1), while 27 had no reduction loss (group 2). The mean longitudinal, transverse, and anteroposterior lengths and joint surface area of the VLF fragment were significantly smaller in group 1 than in group 2. Three-dimensional computed tomography revealed that the fracture patterns of the radiocarpal and distal radioulnar joints in group 1 were mainly volar-displaced VLF fragments. CONCLUSIONS: By stabilizing fragments, distally placed volar locking plate fixation effectively treated intra-articular distal radius fractures with VLF fragments distal to the watershed line. However, the presence of small displaced VLF fragments may increase the risk of reduction loss in ulnar variance.

Obese Children Have Different Forearm Fracture Characteristics Compared With Normal-weight Children.

BACKGROUND: Current estimates suggest that one third of children and adolescents are overweight and 1 in 5 are obese. Obese children are at increased risk of sustaining more complex fractures, failing nonoperative treatment, and experiencing more complications during treatment. The purpose of this study was to compare forearm fracture characteristics, treatment, and complications in grouped overweight and obese [OW+OB; body mass index-for-age percentile (BMI%) ≥85] pediatric patients compared with normal-weight (NW; BMI%≤84) patients. METHODS: This was a retrospective comparative study of patients aged 2 to 17 years old who presented with a forearm fracture resulting from low-energy trauma between January 2010 and September 2017. Patients with incomplete height and weight data; an underlying condition that predisposes to fractures or altered fracture healing; and torus, greenstick, pathologic, and high-energy fractures were excluded. Demographics, fracture characteristics, treatment, and complications were recorded. Descriptive and inferential analyses were conducted. RESULTS: A total of 565 patients (403 NW, 162 OW+OB) met the inclusion criteria. NW children sustained open fractures nearly twice as frequently as the OW+OB children but this was not statistically significant (9.7% vs. 4.9%; P=0.065). Subanalysis showed that NW children were 4.1 times more likely to sustain an open fracture compared with obese (BMI%≥95) children (9.7% vs. 2.4%; P=0.029). A significant relationship was found between BMI% and location of the fracture, the bones involved, and fracture type. The OW+OB children sustained more distal forearm fractures than midshaft and proximal forearm fractures. Isolated radial shaft fractures were more common in the OW+OB group, whereas isolated ulnar shaft fractures were more common in the NW group. There was no difference in associated neurovascular injury, initial nonoperative versus operative management, failure of nonoperative treatment, and treatment complications. CONCLUSIONS: OW+OB children have different forearm fracture characteristics compared with their NW peers. The thick soft tissue envelope in obese children may be protective against an open forearm fracture. In contrast to previous studies, obesity was not associated with failure of nonoperative treatment or a higher rate of complications. LEVEL OF EVIDENCE: Level III-prognostic.

Pronation type Galeazzi-equivalent fracture: A rare case report (CARE-compliant).

RATIONALE: Galeazzi fractures are uncommon, and are less common in children than in adults. Galeazzi-equivalent fractures, a variant of the classic Galeazzi fractures, mostly occur in children or adolescents. Galeazzi equivalent fractures may commonly accompany distal radial fractures or injury of the epiphyseal plate of the distal ulna. PATIENT CONCERNS: A 13-year-old man visited our emergency department after stumbling over a rock. Manual reduction and splinting was already done in a nearby medical center. Plain radiographs revealed fractures in the distal radius and fracture of the ulnar epiphyseal plate. DIAGNOSIS: Plain radiographs showed Galeazzi-equivalent fracture. The result of primary closed reduction was not enough and there was still displacement of fracture. INTERVENTIONS: Anatomical reduction of distal radius was fixed with a plate and screws, and K-wires were inserted percutaneously for reduction and fixation of ulnar fracture. OUTCOMES: Complete bone union was achieved and normal range of motion is shown 2 years postoperatively. The patient is able to perform daily activities and sport activities without any signs of ulnar growth arrest. LESSONS: Open reduction is required in patients with malalignment, failure to reduce the DRUJ or maintain its reduction, or older ages which are hard to expect sufficient bone remodeling.

A Biomechanical Comparison of Three Miniature Locking Plate Systems in a Rabbit Radial and Ulnar Fracture Model.

OBJECTIVE: The aim of this study was to evaluate the biomechanical properties of three different miniature locking plate systems used to fixate radial and ulnar fractures in toy breed dogs. Implant size, shape, material and locking systems differ, and their influence on the fracture healing process is unknown. In the present study, we aimed to investigate this matter in vivo using rabbit radial and ulnar fracture models. STUDY DESIGN: Eighteen rabbits were randomly divided into three groups, and the left radius and ulna were osteotomized to create fracture models. The osteotomies were then fixated using either the TITAN LOCK 1.5, Fixin micro or LCP 1.5 system. Radiographs were obtained 2, 3 and 4 weeks after surgery. Four weeks after surgery, the radiuses were collected and used for biomechanical testing or histological examinations. RESULTS: During the 4 weeks of observation, no adverse effects due to the implants occurred. The radiographic scores in each group did not differ significantly at any time point. The maximum load in the LCP group was significantly higher than that in the TITAN and Fixin groups. There was no significant difference in bending stiffness or work to failure among the groups. Initial fracture healing via woven bone was evident at histological evaluation. CONCLUSIONS: All three miniature locking plate systems provided adequate fracture stabilization 4 weeks after surgery, despite their differences, in rabbit models.

Use of surgical glue for Mason type III radial head fractures: A case report.

RATIONALE: A Mason type III radial head fracture, which is characterized by comminuted fragments of the radial head, is a severe injury. Open reduction and internal fixation (ORIF) is an alternative treatment method; however, the technique of using an on-table reduction in combination with surgical glue is rarely reported. PATIENT CONCERNS: A 48-year-old man was admitted to our department with complaints of elbow pain after falling down. Elbow radiography and computed tomography (CT) demonstrated characteristics of fractures before the operation. DIAGNOSIS: Radiographic images showed a Mason type III radial head fracture. INTERVENTIONS: The patient underwent ORIF at our hospital. During the operation, the technique of on-table reconstruction combined with surgical glue was used. OUTCOMES: The patient recovered well and was able to participate in his usual work. LESSONS: Mason type III radial head fractures could be treated with ORIF, and a satisfactory result could be anticipated, thus avoiding a radial head replacement or resection. Anatomical reduction of a comminuted radial head could be obtained via an on-table reconstruction and application of surgical glue.

Pucker sign in an adult distal radial fracture.

Puckering of the skin following a fracture is a rare sign which can result in skin necrosis if the fracture is not urgently reduced. Skin puckering is associated with humeral, tibia and clavicular fractures. We present a case of a 79-year-old woman who fell on to her outstretched hand sustaining a right radial fracture with obvious skin puckering. Following X-rays, local anaesthetic was given and the skin was reduced, the fracture manipulated and a full cast applied. The patient made a full recovery. To our knowledge, this is the first reported case of the pucker sign in an adult radial fracture.

Bone Microarchitecture and Distal Radius Fracture Pattern Complexity.

Distal radius fractures (DRFs) occur in various complexity patterns among patients differing in age, gender, and bone mineral density (BMD). Our aim was to investigate the association of patient characteristics, BMD, bone microarchitecture, and bone strength with the pattern complexity of DRFs. In this study, 251 patients aged 50-90 years with a radiologically confirmed DRF who attended the Fracture Liaison Service of VieCuri Medical Centre, the Netherlands, between November 2013 and June 2016 were included. In all patients fracture risk factors and underling metabolic disorders were evaluated and BMD measurement with vertebral fractures assessment by dual-energy X-ray absorptiometry was performed. Radiographs of all DRFs were reviewed by two independent investigators to assess fracture pattern complexity according to the AO/OTA classification in extra-articular (A), partially articular (B), and complete articular (C) fractures. For this study, patients with A and C fractures were compared. Seventy-one patients were additionally assessed by high-resolution peripheral quantitative computed tomography. Compared to group A, mean age, the proportion of males, and current smokers were higher in group C, but BMD and prevalent vertebral fractures were not different. In univariate analyses, age, male gender, trabecular area, volumetric BMD (vBMD), and stiffness were associated with type C fractures. In multivariate analyses, only male gender (odds ratio (OR) 8.48 95% confidence interval (CI) 1.75-41.18, p = 0.008]) and age (OR 1.11 [95% CI 1.03-1.19, p = 0.007]) were significantly associated with DRF pattern complexity. In conclusion, our data demonstrate that age and gender, but not body mass index, BMD, bone microarchitecture, or strength were associated with pattern complexity of DRFs.© 2019 The Authors. Journal of Orthopaedic Research® Published by Wiley Periodicals, Inc. J Orthop Res 37:1690-1697, 2019.

Distal radial torus fracture in an adult. A new type of occult wrist fracture?

Torus or buckle fractures typically affect children who have suffered indirect minor wrist injuries. They are axial compression-type metaphyseal fractures of cortical and cancellous bone, which are stable and their treatment therefore consists in immobilisation of the joint for three to four weeks. We present an atypical case of distal radius torus fracture in a 19-year-old adult male, which has not been previously reported in adults and can be considered a new type of occult fracture. Knowledge of this possibility is mandatory to be able to make a differential diagnosis of wrist sprain in adults, and avoid performing superfluous complementary tests due to the persistence of pain and functional incapacity.

Altered gene and protein expressions of vitamin D receptor in skeletal muscle in sarcopenic patients who sustained distal radius fractures.

Despite the presence of vitamin D receptor (VDR) in skeletal muscle cells, the relationship between VDR expressions and muscle mass or function has not been well studied. The purpose of this study was to compare VDR gene and protein expression in the forearm muscle between sarcopenic and non-sarcopenic individuals who have sustained distal radius fractures. Twenty samples of muscle tissue from sarcopenic patients (mean age 63.4 ± 8.1 years) and 20 age- and sex-matched control tissues (62.1 ± 7.9 years) were acquired from the edge of dissected pronator quadratus muscle during surgery for distal radius fractures. The mRNA expression levels of VDR as well as the myokines of interest that may be associated with muscle mass change (myogenin and myostatin) were analyzed with real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). In addition, Western blot assay and immunohistochemistry for VDR were performed. Sarcopenic patients showed a significantly lower level of gene expression for VDR and myogenin, but a greater level of gene expression for myostatin than the controls according to qRT-PCR analysis. The density of VDR protein expressions was 2.1 times greater, while that of myostatin was 2.6 times lower, in the control group than in the sarcopenic group according to Western blot analysis. On immunohistochemical analysis, the density of the cells expressing VDR was significantly decreased in the sarcopenic patients. Sarcopenic patients who sustained distal radius fractures presented lower vitamin D receptor gene and protein expression in skeletal muscles compared to non-sarcopenic individuals.

Classification of the transverse pattern of Mason II radial head fractures and its usefulness in arthroscopic osteosynthesis. Anatomo-surgical study. / Clasificación del patrón transversal de las fracturas de la cabeza del radio tipo Mason II y su utilidad en la osteosíntesis mediante técnica artroscópica. Estudio anatomoquirúrgico.

OBJECTIVE: The management of MasonII fracture pattern assisted by arthroscopy is a valid technique that provides good results. The objective of this study was to draw attention to the usefulness of the location of the fracture in the head of the radius in defined quadrants with respect to the bicipital tuberosity through CT. This would help to plan the optimal forearm position to access each quadrant and foresee the specific difficulties of each one. MATERIAL AND METHOD: We dissected 4 specimens of cryopreserved cadaver. We divided the radial head into 4 quadrants with regard to the bicipital tuberosity, objectifying the change of position in pronation and maximum supination with respect to the sigmoid cavity and neurovascular structures. RESULTS: The head of the radio moves with pronosupination, so there are areas of convergence between the different quadrants. Quadrant1 is approached in supination via an anteromedial portal. Quadrant2 is approached in maximum pronation through a lateral portal. Quadrant3 can be approached through lateral portals, with the forearm in neutral position and in pronation. Quadrant4 is accessible with the forearm in a neutral position and in supination through a lateral portal. CONCLUSIONS: Depending on the location of the fracture in the head of the radius with respect to the bicipital tuberosity, we will need access through a specific arthroscopic portal, with the medial quadrants (anteromedial and posteromedial) being the most technically demanding.

Integrating 3D Printing and Biomimetic Mineralization for Personalized Enhanced Osteogenesis, Angiogenesis, and Osteointegration.

Titanium (Ti) alloy implants can repair bone defects at load-bearing sites. However, they mechanically mismatch with the natural bone and lack customized adaption with the irregularly major-sized load-bearing bone defects, resulting in the failure of implant fixation. Mineralized collagen (MC), a building block in bone, can induce angiogenesis and osteogenesis, and 3D printing technology can be employed to prepare scaffolds with an overall shape customized to the bone defect. Hence, we induced the formation of MC, made of hydroxyapatite (HAp) nanocrystals and collagen fibers, in 3D-printed porous Ti6Al4V (PT) scaffolds through in situ biomimetic mineralization. The resultant MC/PT scaffolds exhibited a bone-like Young's modulus and were customized to the anatomical contour of actual bone defects of rabbit model. We found that the biocompatibility and osteogenic differentiation are best when the mass ratio between HAp nanocrystals and collagen fibers is 1 in MC. We then implanted the MC/PT scaffolds into the customized radius defect rabbit model and found that the MC/PT scaffolds significantly improved the vascularized bone tissue formation and integration between new bone and the implants. Therefore, a combination of 3D printing and biomimetic mineralization could lead to customized 3D PT scaffolds for enhanced angiogenesis, osteogenesis, and osteointegration. Such scaffolds represent novel patient-specific implants for precisely repairing irregular major-sized load-bearing bone defects.

Effects of concentrated growth factors (CGF) on the quality of the induced membrane in Masquelet's technique - An experimental study in rabbits.

AIMS: The aim of the study was to test if the addition of CGF to the Masquelet technique contributes to the quality of the membrane formed surrounding the polymethylmethacrylate (PMMA), in terms of inflammation, proliferation and vasculazition in the Masquelet technique in the early and late phases in a rabbit model. MATERIALS AND METHODS: A critical bone defect of 15 mm was created in radius diaphysis, leaving 3 cm of intact bone to the joint. To mimic the Masquelet technique and to increase stability, a 6-hole 1.5 mm plate with two screws was applied, although it was initialy stable because of the inherently fixed ulna and radius both proximally and distally in the rabbits. Group 1 and Group 3, were soleley treated with the Masquelet technique as control groups, and were sacrificed at 3 and 6 weeks, respectively. Group 2 and Group 4, were treated with the Masquelet technique + CGF prepared from the rabbit blood groups, and were sacrificed at 3 and 6 weeks, respectively. The groups were compared histopathologically and immunohistochemically, in respect of the means of thickness of the membrane and ratio of elastic fibers, membrane vascularization (CD31), inflammation (MAC387), proliferation (Ki67), and presence of stem cells (STRO-1). RESULTS: Thickness of the membrane and CD31 values were significantly higher in Group 4 than Group 3 (p = 0.004 for both). MAC387 was statistically significantly higher in Group 2 compared to Group 1 and Group 4 compared to Group 3 (p = 0.04 for both). Ki67 was significantly higher in Group 2 compared to Group 1 and Group 4 compared to Group 3 (p = 0.05 and p = 0.006, respectively). Proliferation in the membrane was statistically significantly higher in Group 2 compared to Group 1 (p = 0.05). Likewise, the proliferation index of Group 4 was statistically significantly higher than Group 3 (p = 0.06). STRO-1 was significantly higher in Group 2 compared to Group 1 (p = 0036). CONCLUSION: The addition of CGF to the Masquelet technique contributes to the quality of the membrane formed, in respect of inducing inflammation and proliferation, maintaining vascularization on large diaphyseal bone defects, and increasing the number of stem cells.

The Sigmoid Notch View for Distal Radius Fractures.

PURPOSE: This study defines the sigmoid notch view of the distal radius. Specifically, we tested the null hypothesis that there is no relationship between the subchondral stripe of bone seen on a sigmoid notch view of the distal radius and the articular surface of the sigmoid notch. METHODS: We used 44 wrist specimens for anatomic and fluoroscopic analysis. We measured the articular depth of the sigmoid notch from its deepest point and classified the shape of the sigmoid notch. We then placed a radiopaque marker at the nadir of the articular surface and quantified the fluoroscopic depth of the sigmoid notch. A sigmoid notch view, which was a tangential fluoroscopic view of the volar and dorsal lips of the sigmoid notch, was obtained. The relationship of the articular surface to the stripe of subchondral bone seen on this view, called the sigmoid stripe, was determined. RESULTS: Anatomic analysis revealed sigmoid notch types with proportions similar to those in previous descriptions. The marker for the articular surface was superimposed or just ulnar to the sigmoid stripe in all specimens. In flat face and ski slope notches, this was coincident with the volar and dorsal lips of the sigmoid notch. In C- and S-type notches, there was a measurable distance from the articular surface marker to the edges of the bone of the volar and dorsal lips of the sigmoid. CONCLUSIONS: The articular surface marker at the nadir of the sigmoid notch is always coincident or ulnar to the sigmoid stripe in the sigmoid notch view. CLINICAL RELEVANCE: Surgeons can use the sigmoid notch view as a reliable method to (1) evaluate the integrity of the articular surface, (2) ensure hardware is not placed in the distal radioulnar joint, and (3) guide placement of volar locking plates in the coronal plane.