Edward Harvey

Glucocorticoid (GC) usage is the most common non-traumatic cause of osteonecrosis of the femoral head (ON). Despite the strong association of GC with ON, the underlying mechanisms have been unclear. Investigators have proposed both direct and indirect effects of GC on cells. Indirect and direct mechanisms remain intimately related and often result in positive feedback loops to potentiate the disease processes. However, the direct effects, in particular apoptosis, have recently been shown to be increasingly important. Suppression of osteoblast and osteoclast precursor production, increased apoptosis of osteoblasts and osteocytes, prolongation of the lifespan of osteoclasts and apoptosis of endothelial cells (EC) are all direct effects of GC usage. Elevated blood pressure through several pathways may raise the risk of clot formation. High-dose GC also decreases tissue plasminogen activator activity (t-PA) and increases plasma plasminogen activator inhibitor-1 (PAI-1) antigen levels in...

BACKGROUND: Immediate primary closure of open fractures has been historically believed to increase the risk of wound infection and fracture nonunion. Recent literature has challenged this belief, but uncertainty remains as to whether primary closure can be used as routine practice. This study evaluates the impact of an institutional protocol mandating primary closure for all open fractures. METHODS: We retrospectively reviewed all open fractures treated in a single level 1 trauma centre in a 5-year period. Prior to the study, a protocol was adopted standardizing management of open fractures and advocating primary closure of all wounds as a necessary goal of operative treatment. Patient and fracture characteristics, type of wound closure and development of infectious and bone healing complications were evaluated from time of injury to completion of outpatient follow-up. RESULTS: A total of 297 open fractures were treated, 255 (85.8%) of them with immediate primary closure. Type III open injuries accounted for 24% of all injuries. Wounds that were immediately closed had a superficial infection rate of 11% and a deep infection rate of 4.7%. Both proportions are equivalent to or lower than historical controls for delayed closure. Fracture classification, velocity of trauma and time to wound closure did not correlate significantly with infection, delayed union or nonunion. CONCLUSION: Attempting primary closure for all open fractures is a safe and efficient practice that does not increase the postoperative risk of infection and delayed union or nonunion.

Traditional short nail fixation devices used for intertrochanteric (IT) fractures of the femur have several surgeon and patient benefits. However, these devices have had a high incidence of complications. A new intramedullary device designed to overcome these shortcomings has become commercially available. The goal of this study was to compare this intramedullary nail device with the traditional dynamic hip screw. A prospective cohort study with 60 IT hip fractures was performed. Thirty patients treated with the trochanteric fixation nail (TFN) were compared with 30 patients treated with the dynamic hip screw (DHS) during the same time period. Implant selection was dictated by surgeon randomization. Primary outcomes planned for this study were immediate measures of operative blood loss, surgical time, and incidence of operative complications. Secondary outcome of return to preoperative ambulatory status was also recorded. Follow-up for secondary outcomes was conducted at an average of 6 months after surgery. Perioperative, functional, and radiologic outcome measures were collected. No intra- or perioperative complications occurred with the new nail device. Operative time was 10 minutes shorter with TFN (50.7 minutes) compared with DHS (60.4 minutes). No Trendelenburg gait was noted in either group. No femur fractures or distal locking difficulties occurred in the TFN group. Twelve of 17 (71%) TFN patients returned to prefracture ambulation 6 months after surgery compared with only 6 of 18 (33%) DHS patients (p = 0.09). The rate of femoral fractures for short femoral nails was decreased compared with historical controls. Improved early mobilization was noted in TFN group.

Glucocorticoid usage especially at high doses is complicated by adverse outcomes such as thrombotic events or acceleration of inflammatory response in conditions like myeloma and osteonecrosis. The mechanism(s) through which high-dose dexamethasone (HDDEXA) causes vascular injury remains unclear. We hypothesized that HDDEXA sensitizes endothelial cells (EC) to the effect of inflammatory mediators and modulates endothelial haemostatic gene expression and leukocyte adhesion. Human umbilical vein endothelial cells (HUVECs) were grown in the absence or presence of HDDEXA and were also tested in the presence or absence of tumor necrosis factor-alpha (TNF-alpha), lipopolysaccharide (LPS) or thrombin. mRNA and protein expression were measured and the functional consequences of HDDEXA preconditioning on cell adhesion molecules (CAM) were determined by agonist-mediated leukocyte adhesion assay. Treatment with HDDEXA resulted in an increased induction of CAM, tissue factor and von Willebrand factor, while down-regulating thrombomodulin and urokinase. HDDEXA alone had no effect on adhesion but resulted in enhanced TNF-alpha- and LPS-mediated adhesion of neutrophils. Together, these findings suggest that HDDEXA sensitizes HUVEC to the effect of inflammatory mediators and induces a pro-adhesive environment in primary EC. This finding is of importance when glucocorticoid usage is required at therapeutic high doses in patients with or without thrombotic risk factors.

Several surgical options have been used for the repair of scapholunate instability over the last 50 years. The many options have included neglect, reduction with percutaneous pinning, primary repair, partial fusions, tendon weaves, and others. Recent advancements in scapholunate repair and anatomy have been aimed at a more physiological repair. Composite replacement of the entire scapholunate interval similar to other tendon repairs seen in orthopedic surgery has become popular. Currently, more common hand-based grafts are bone-retinaculum-bone, third or second metacarpal-carpal bone or hamate-capitate grafts. There still exist some failures in the outcome after any of these procedures. This technique demonstrates the use of a vascularized autograft replacement on a pedicled graft. This procedure is the natural extension of the third or second metacarpal-carpal bone autograft, previously reported in the literature. The use of this proven graft, with a pedicle based on the intermetacarpal artery, may avoid some of the late complications seen with other autografts.

Retrospective analysis of a prospectively followed cohort. Long-term evaluation of patients with anterior stabilization for dislocations of the cervical spine. Level 1 trauma center. Anterior stabilization of unstable cervical spine injuries is gaining popularity. However, the method of open reduction is controversial. Forty-one consecutive patients with unstable dislocations/subluxations of the subaxial cervical spine were included. Closed reduction was attempted in all patients using Gardner-Wells traction. If this failed, an anterior open reduction was performed. Tricortical iliac crest autograft and anterior plating was used. Patients were assessed for: 1) rate of successful reduction and stabilization using only the anterior surgical approach; and 2) complications and long-term clinical and radiologic outcome. Two of eight (25%) anterior open reductions failed requiring posterior surgery. One of these patients had associated pedicle fractures with horizontal rotation of the lateral masses. All grafts had healed successfully at the most recent follow-up visit. Moderate neck discomfort was found in 5 of 41 patients. Significant neurologic improvement was observed. Most subluxations/dislocations of the subaxial cervical spine can be reduced using Gardner-Wells traction and successfully stabilized with anterior surgery alone. If closed reduction fails, anterior open reduction is successful in the majority of cases.

To determine the prevalence and predictive factors for early cast alteration (splitting, trimming, complete replacement) in patients with distal radius fractures (DRFs) treated in circumferential cast. To determine if performing early cast alterations affects fracture alignment. Retrospective Cohort Study SETTING:: Level 1 Trauma Center PATIENTS:: All adult patients who presented with a DRF to a tertiary care hospital over a three-year period. All DRFs without immediate surgical indications are initially treated with circumferential casts at this center. The following variables were analyzed: patient demographics, polytrauma at time of injury, physician subspecialty performing reduction and type of cast alteration. Radiographs were used to assess initial fracture characteristics and secondary displacement of reduction over time. Analysis was performed primarily to identify predictive variables for early cast alteration, and secondarily to determine the effect of these alterations on fracture alignment. 296 patients were included in the study. One out of every 4-5 patients had their cast altered within the first 10 days of treatment. One out of 3 polytrauma patients had their cast altered. No type of cast alteration was found to be significantly predictive of loss of fracture alignment at 2 or at 6 weeks. Cast alteration is commonplace after casting of distal radius fractures, but is not associated with loss of alignment. Polytrauma patients may benefit from immediate cast splitting. Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Nanotechnology and its attendant techniques have yet to make a significant impact on the science of bone healing. However, the potential benefits are immediately obvious with the result that hundreds of researchers and firms are performing the basic research needed to mature this nascent, yet soon to be fruitful niche. Together with genomics and proteomics, and combined with tissue engineering, this is the new face of orthopaedic technology. The concepts that orthopaedic surgeons recognize are fabrication processes that have resulted in porous implant substrates as bone defect augmentation and medication-carrier devices. However, there are dozens of applications in orthopaedic traumatology and bone healing for nanometer-sized entities, structures, surfaces, and devices with characteristic lengths ranging from 10s of nanometers to a few micrometers. Examples include scaffolds, delivery mechanisms, controlled modification of surface topography and composition, and biomicroelectromechanical systems. We review the basic science, clinical implications, and early applications of the nanotechnology revolution and emphasize the rich possibilities that exist at the crossover region between micro- and nanotechnology for developing new treatments for bone healing.

Fracture healing is an extremely complex interaction of cells, biologic pathways, and molecules. Certainly, the inflammatory response is one of the initiating factors for bone healing. The inflammatory phase is a critical period characterized by low oxygen tension, impaired perfusion, and the migration of a wide array of cells and release of active molecules. Systemwide inflammatory conditions also modulate the primary processes of fracture management. Osteoprogenitor cells, mesenchymal cells, osteoblasts, and chondrocytes contribute to the healing and inflammatory response at the bone level. The inflammatory process is dependent on and propagates through proinflammatory cytokines, the transforming growth factor-beta superfamily with other growth factors, and the metalloproteinases and angiogenic factors. Interference with any of these pathways or proteins either promotes or more likely decreases fracture healing. This article reviews the initial inflammatory response to trauma as it pertains to musculoskeletal healing.

An ideal replacement for the scapholunate ligament (SLL) has not been found. The carpometacarpal bone-ligament-bone complex at the base of the second and third metacarpal is proposed as a replacement for the SLL in this study. A cadaveric study of matched SLL, second metacarpal-trapezoid ligament, third metacarpal-capitate ligament, and dorsal periosteal retinaculum was performed. Stiffness and strength were obtained from fresh-frozen specimens tested to failure with a hydraulic distractor. The second metacarpal-trapezoid ligament and the third metacarpal-capitate ligament most closely approximated the stiffness and strength of the SLL. The dorsal periosteal retinaculum was significantly less stiff and was significantly weaker than the SLL. This study indicates that the second or third carpometacarpal ligaments are grafts that approximate the mechanical properties of the SLL.

Radial-sided avulsions of the triangular fibrocartilage complex (TFCC) (Palmer 1D) with distal radioulnar joint (DRUJ) instability remain a challenging pathology to treat. We tested an intra-articular reconstruction that addresses unstable radial-sided TFCC avulsions. Ten preserved, dissected, cadaveric forearm specimens with intact TFCC and without ulnar-positive variance had biomechanical testing using a hydraulic testing device. The measurement of total displacement of the ulna relative to the radius was performed with an applied load ranging from 20 N in a volar direction to 20 N in a dorsal direction. Specimens were tested sequentially with intact TFCC, with surgically induced Palmer 1D lesions, and after reconstruction of the TFCC. All tests were performed at neutral, maximal pronation, and maximal supination. The mean total displacements of the DRUJ of the specimens at neutral rotation were as follows: 4.1 +/- 0.4 mm for the intact specimens compared with 11.8 +/- 0.8 mm after creation of the tear and 3.9 +/- 0.7 mm for the reconstructed specimens. In maximal pronation the mean total displacements were as follows: 2.4 +/- 0.3 mm intact versus 4.9 +/- 0.7 mm for torn and 2.1 +/- 0.3 mm after reconstruction. In maximal supination the mean total displacements were as follows: 1.4 +/- 0.2 mm intact versus 5.7 +/- 1.3 mm for torn and 1.0 +/- 0.1 mm after reconstruction. All specimens obtained the preoperative pronation and supination motion after the reconstruction. Current procedures are unable to restore DRUJ stability without a significant limitation of pronation and supination. This intra-articular reconstruction of radial-sided TFCC avulsions succeeded in restoring baseline stability to the DRUJ without interfering with pronation/supination.

A retrospective chart and radiographic review was performed of 37 operative procedures over 7 years period for peri-articular nonunions. This was a consecutive cohort from a single orthopedic trauma service of a Level 1 center. Nonunions of the tibia and humerus were treated with blade plates fashioned from standard compression plates. Twenty-nine operative sites were treated successfully. The average age was 45.0 years; the average follow-up being 5.3 years. The average number of operations before blade plate was 4.0 (range 1-16). Sixteen blade plates were performed in patients with a diagnosis of clinical infection and all progressed to union and resolution of infection. Seven tissue transfers were used as adjunctive therapy. Five other patients with blade plate surgery had persistent nonunion, of which four united after a second custom contoured blade plate procedure. This study illustrates that surgeon contoured blade plates are an option for peri-articular nonunions even in the presence of infection. This technique resulted in a high union rate and a low complication rate compared to other options.

In countries with universal health care systems patients frequently wait days for their "emergency" surgery. A general trend in orthopaedic traumatology is the advent of daily, dedicated orthopaedic trauma theatres. Availability of trauma theatres is believed to decrease morbidity and mortality, but this remains unproven. A retrospective review comparing morbidity and mortality outcomes between two similar level-one trauma centres (one without a dedicated trauma room system) was undertaken. We reviewed 701 elderly patients receiving hemiarthroplasties for displaced subcapital hip fractures over a 76-month period. Patients were similar between centres in terms of age, gender ratio and comorbidities. Statistically significant differences were found favouring the dedicated trauma room system with approximately half the operative delay and post-operative morbidity. A trend towards decreased mortality was also seen. This study supports the use of regular orthopaedic trauma theatres in tertiary care institutions.

The purpose of this study was to determine which screws could be safely inserted percutaneously into a proximal humerus locking plate using a new external aiming guide without injuring the axillary nerve. We also sought to evaluate that all the screws could be accurately inserted ina locked position with the external guide. Eight cadaveric specimens were implanted with a proximal humerus locking plate using a minimally invasive direct-lateral deltoid splitting approach using an attached external aiming guide for screw insertion. The anatomic proximity of the axillary nerve to the guidewires and screws was measured following soft tissue dissection and inspection of the nerve. The two superior holes (C1 and C2) were proximal to the axillary nerve with an average distance of 15.1 mm. Screw F was on average 6.6 mm distal to the axillary nerve but within 2 mm of the nerve in two specimens. In all specimens, the locking screws were appropriately seated in a locked position using the external aiming guide. This study suggests that percutaneous fixation of a proximal humerus locking plate with an external aiming guide can be safely used for proximal humerus fractures. The limited number of screws that can be inserted into the proximal fragment using the current external guide arm may compromise fixation of more unstable fractures. Therefore, the indications for percutaneous locking plate fixation of the proximal humerus using an external aiming guide should be limited to stable fracture patterns that can be anatomically reduced.

No area of fracture management has had such a recent explosion of new treatment modalities as distal radius plating. This explosion has largely been implant- and industry-driven, with little evidence-based research guiding the way. A perceived difficulty with commonly used modalities by the orthopedic community has been enough to drive an entire new set of options for distal radius fixation. A drift from dorsal to volar plating has occurred that has been unexamined by randomized research. Segment specific fixation has been a new mindset that has resulted in a novel plate line and has caused other manufacturers to redesign their product lines. Other novel approaches for proposed problems include locking plates, nail-plate combinations, and others. This article outlines some of these options with a literature opinion and a clarification from the authors. A treatment plan for common fractures of the distal radius is also outlined.

Historically, the etiology of local bone pathologies, such as avascular necrosis, has been related to intravascular occlusion. Recent reports have highlighted the occlusion of arteries, venules, and/or capillaries in bone tissue. Endothelium of bone presumably participates locally in the formation of the microvascular thrombosis. It is also known that endothelial cells (ECs) play a central role in angiogenesis, a process seen in osteosarcoma, amongst other bone diseases. Given the well-recognized heterogeneity of ECs throughout the body, investigations of local bone disease related to endothelium processes may be more appropriately targeted on bone ECs rather than other primary ECs or an immortalized EC line. In the current study, mechanical and enzymatic methods are described to isolate ECs from cancellous human bone tissue followed by immunomagnetic bead separation to purify the cell populations. The human bone-derived endothelial cells (hBDECs) were characterized based on endothelial cell antigen expression and functional assays. This study is the first report of isolation and expansion of ECs from human bone tissue. Isolation of hBDECs in human vascular bone diseases may facilitate the study of the molecular and/or genetic abnormalities in the vasculature system that contributes to the initiation and/or progression of the disease.

Vascular hypotheses provide compelling pathogenic mechanisms for the etiology of avascular necrosis of the femoral head (ANFH). A decrease in local blood flow of the femoral head has been postulated to be the cause of the disease. Several studies in human and animal models of ANFH have shown microvascular thrombosis. Endothelial cell damage could be followed by abnormal blood coagulation and thrombus formation with any resulting degeneration distal to the site of vascular occlusion. Other studies suggest that thrombophilia, particularly impaired fibrinolysis, plays a potential role in thrombus formation in ANFH. Reduction in shear stress due to decreased blood flow could lead to apoptosis of endothelial cells, which can ultimately contribute to plaque erosion and thrombus formation. Dysregulation of endothelial cell activating factors and stimulators of angiogenesis or repair processes could also affect the progression and outcome of ANFH. Likewise, regional endothelium dysfunction (RED), referred to as a potential defect in endothelial cells located in the feeding vessels of the femoral head itself, may also have a crucial role in the pathogenesis of ANFH. Molecular gene analysis of regional endothelial cells could also help to determine potential pathways important in the pathogenesis of ANFH.

Osteoconductive coatings may improve the clinical performance of implanted metallic biomaterials. Several low-temperature coating methods have been reported where a supersaturated solution is used to deposit typically apatitic materials. However, due to the very low solubility of apatite, the concentration of calcium and phosphate ions attainable in a supersaturated solution is relatively low ( approximately 1-2mM), thus coating formation is slow, with several solution changes required to form a uniform and clinically relevant coating. In order to avoid this problem, we present a novel method where substrates were initially sputter coated with pure magnesium metal and then immersed in differing phosphate solutions. In this method, upon immersion the implant itself becomes the source of cations and only the anions to be incorporated into the coating are present in solution. These ions react rapidly, forming a continuous coating and avoiding problems of premature non-localized precipitation. The different coatings resulting from varying the phosphate solutions were then characterized in terms of morphology and composition by microscopy and chemical analyses. Upon immersion of the sputter-coated metals into ammonium phosphate solution, it was found that a uniform struvite (MgNH(4)PO(4).6H(2)O) coating was formed. Upon subsequent immersion into a calcium phosphate solution, stable coatings were formed. The coated surfaces also enhanced both osteoblastic cellular adhesion and cell viability compared to bare titanium. The concept of sputter-coating a reactive metal to form an adherent inorganic metal coating appears promising in the field of developing rapid-forming low-temperature bioceramic coatings.