Orthogenomics: an update.

The study of genomics in orthopaedics has considerably lagged behind such study in other medical disciplines. Seminal work from other lines of medical research demonstrates the importance of genomic information in the evolution of personalized medicine. Common techniques for studying genome-phenotype associations include single nucleotide polymorphism, haplotype, and quantitative trait loci analysis. The few genome-based studies in major orthopaedic and related conditions have focused on osteoporosis, osteoarthritis, neuropathy and nerve compression, spinal deformity, trauma and inflammatory response, and pain and analgesia. The nascent field of orthogenomics, newly defined here as the application of genomic study to orthopaedic practice, has produced findings that could affect the practice of orthopaedics. However, more work is required, and the findings must be distilled and harnessed into applicable and achievable steps to improve clinical orthopaedic practice.

Delayed flap reconstruction with vacuum-assisted closure management of the open IIIB tibial fracture.

OBJECTIVE: Vacuum-assisted closure (VAC) therapy has been shown to be effective at reducing bacterial counts in wounds until definitive bony coverage. However, there is continued debate over timing and type of definitive wound coverage even with VAC therapy application. METHODS: From 2004 to 2009, 32 patients with Gustilo type IIIB open tibia fractures were initially treated with VAC therapy were included. The number of debridements, length of treatment with VAC dressing, definitive wound coverage management, and length of hospital stay, flap-related complications, and time to radiographic fracture healing were recorded. RESULTS: The mean Injury Severity Score was 17.3 ± 2.0. All wounds closed after being treated with the primary VAC closure. The mean interval between the initial injury and definitive intervention was 10.9 days ± 0.3 days. Twenty of 27 patients (74%) underwent rotational muscle flaps; four received free muscle flaps and three only with split-thickness skin grafts for definitive wound coverage. Nine of 32 patients (28%) underwent below knee amputation, five without flap coverage after several VAC sessions and four after definitive flap coverage. The average time to union was 10.0 months ± 2.0 months. Eight patients developed nonunion and 11 patients developed infections. The average follow-up time is 2.4 years ± 0.2 years. Patients were divided into two groups for analysis according to the interval time. The rate of infection was significantly increased in patients who had an interval of more than 7 days from the time of injury to flap coverage. CONCLUSIONS: The VAC therapy may help to reduce the flap size and need for a flap transfer for type IIIB open tibial fractures. However, prolonged periods of VAC usage, greater than 7 days, should be avoided to reduce higher infection and amputation risks.

Treatment of interprosthetic fractures of the femur.

BACKGROUND: The treatment of interprosthetic femoral fractures is challenging because of several factors. Poor bone stock, advanced age, potential prosthetic instability, and limited fracture fixation options both proximally and distally can complicate standard femur fracture treatment procedures. The purpose of this report was to describe our experience treating interprosthetic femoral fractures, providing an emphasis on treatment principles and specific intraoperative management. METHODS: All patients with fractures occurring between ipsilateral hip and knee prostheses between 2004 and 2010 were identified from a comprehensive database and included in this study. Patients had been treated using principles adapted from two isolated periprosthetic fracture classification systems, the Vancouver and Su classifications. The electronic medical record (including inpatient medical records, operative notes, outpatient medical records, and all radiographs) was reviewed for each patient and demographic and treatment-related variables as well as complications and outcomes were recorded. RESULTS: Thirteen consecutive patients with interprosthetic fractures were included. Four fractures occurred around a clearly loose prosthesis, which were subsequently treated with long-stemmed revisions. The remaining 12 fractures were treated with a locked-plate construct. Two of nine patients (22.2%) died before fracture union. Follow-up averaged 28 months ± 4 months, with fracture union achieved at an average of 4.7 months ± 0.3 months. All patients returned to their self-reported preoperative ambulatory status except one who developed a loose hip prosthesis at 3-year follow-up after fracture union. CONCLUSIONS: The principles for treatment of isolated periprosthetic fractures are useful to guide the fixation of interprosthetic fractures. Locked plating is an effective method for the treatment of interprosthetic femoral fractures. Bypassing the adjacent prosthesis by a minimum of two femoral diameters is a necessary technique to prevent a stress riser.

Peroneal tenography to evaluate lateral hindfoot pain after calcaneal fracture.

BACKGROUND: Lateral hindfoot pain after union of a calcaneal fracture remains a challenge to orthopaedic surgeons. This study aimed to investigate the relationship between lateral calcaneal pain, calcaneal width and peroneal tendon sheath impingement in patients with lateral hindfoot pain. MATERIALS AND METHODS: Seventy-four consecutive patients with unilateral lateral hindfoot pain were identified from an institutional trauma registry. Regular followups were performed and the severity of lateral hindfoot pain was recorded. CT scans were conducted to measure calcaneal width at the level of sustentaculum tali. Bilateral peroneal tenography was performed to examine compression of the peroneal tendon sheath. The sheaths on the injured, painful side were compared to the contralateral sheath at the same level. The data was analyzed with bivariate correlation using SPSS 13.0 for Windows. RESULTS: The injured calcanei were wider in all patients and the peroneus longus and brevis tendon sheaths were compressed on peroneal tenography in 68.9% (51 of 74). Statistics demonstrated significant correlations between compression of tendon sheaths and lateral hindfoot pain (Rs = 0.93, p < 0.001), and between increasing calcaneal width and lateral hindfoot pain (Rs = 0.665, p < 0.001). The severity of lateral hindfoot pain was directly correlated to tendon sheath impingement and indirectly related to calcaneal widening. CONCLUSION: Calcaneal widening following fracture union was the cause of compression of the peroneal tendons. Increasing compression correlated with increasing levels of lateral pain. Our study demonstrated the utility of peroneal tenography in identifying the presence of peroneal tendon impingement in patients with lateral pain following calcaneal fractures.

The past, present, and future management of hemodynamic instability in patients with unstable pelvic ring injuries.

Pelvic ring injuries presenting in hemorrhagic shock have historically had a mortality rate greater than 30%. To address this high mortality rate our institution has had a multi-disciplinary protocol for hemodynamically unstable pelvic ring injuries since 1993. In 2004, this protocol was revised to prioritize pre-peritoneal pelvic packing over angiography to rapidly control hemorrhage, reduce high-volume blood transfusions, and decrease the number of deaths from acute blood loss. This protocol has been successful in reducing deaths from hemorrhage by 30%. Despite the benefits of such a protocol, many trauma centers are not routinely stabilizing pelvic ring injuries or controlling pelvic hemorrhage. Subsequently, mortality rates remain high with a significant proportion of patients dying from acute blood loss. Trauma centers adhering to multi-disciplinary protocols that allow for rapid stabilization of the pelvis and simultaneous control of multiple sites of hemorrhage in hybrid operative suites are promising future directions for the management of patients with these lethal injuries.

Prediction of pulmonary morbidity and mortality in patients with femur fracture.

BACKGROUND: We aimed to determine the effect of femur fractures on mortality, pulmonary complications, and adult respiratory distress syndrome (ARDS). In addition, we aimed to compare the effect of femur fractures with other major musculoskeletal injuries and to determine the effect of timing to surgery on these complications. METHODS: All patients were identified from the trauma registries of two Level I trauma centers. Outcomes were defined at mortality in hospital, pulmonary complications, and ARDS in hospital. Regression analysis was used to determine the effect of femur fractures, while controlling for age, Abbreviated Injury Scales, Glasgow Coma Scale, and systolic blood pressure at presentation. We compared femur fractures with other major musculoskeletal injuries in similar models. Within the patients with femur fracture, time to surgery (< 8 hours, 8 hours to 24 hours, and > 24 hours) was evaluated using similar regression analysis. RESULTS: Of the total 90,510 patients, 3,938 (4.35%) died in the hospital, 2,055 (2.27%) had a pulmonary complication, and 285 (0.31%) developed ARDS. Femur fracture is statistically predictive of mortality (odds ratio [OR], 1.606; 95% confidence interval [CI], 1.288-2.002) and pulmonary complications (OR, 1.659; 95% CI, 1.329-2.070), when controlling for other injury factors. This was comparable with the effect of pelvic fracture and other major musculoskeletal injuries. Femur fracture had a strong relationship with ARDS (OR, 2.129; 95% CI, 1.382-3.278). Patients treated in the 8 hours to 24 hours window had the lowest mortality risk (OR, 0.140; 95% CI, 0.052-0.375), and there was a trend to increased risk of ARDS in a delay to surgery of > 24 hours. CONCLUSIONS: Femur fractures are a major musculoskeletal injury and increase the risk of mortality and pulmonary complications as much as any other musculoskeletal injuries. There is a unique relationship between ARDS and femur fractures, and this must be considered carefully in treatment planning for these patients.

Stress radiograph to detect true extent of symphyseal disruption in presumed anteroposterior compression type I pelvic injuries.

BACKGROUND: The differentiation between anteroposterior compression (APC)-I and APC-II pelvic fracture patterns is critical in determining operative versus nonoperative treatment. We instituted a protocol in which a stress examination was performed for patients presenting with an APC-I injury diagnosed with static radiographs to reveal the true extent of the injury. METHODS: During a 4-year study period, we performed 22 stress radiographs in patients with a presumed APC-I injury, which showed symphyseal diastasis ≥ 1.0 cm but <2.5 cm on initial anteroposterior (AP) radiographs of the pelvis or on axial images of the pelvis on computed tomography (CT) scans. In the operating room, a radiopaque marker of known diameter was placed on the skin over the pubic symphysis. A direct AP load was manually applied to both anterior superior iliac spines, and diastasis of the pubic symphysis was measured on stress fluoroscopic images. RESULTS: The mean distance of symphyseal diastasis was 1.8 cm on the AP radiographs, 1.4 cm on the CT scans, and 2.5 cm on fluoroscopic images under a stress examination. Six of 22 patients (27.2%) demonstrated a symphyseal diastasis of >2.5 cm during the stress examination, which changed their treatment from nonoperative to operative. CONCLUSIONS: Measurements of symphyseal diastasis can significantly vary depending on the radiographic modality (CT vs. plain films) and during application of a stress force. The use of stress examination under general anesthesia in the acute setting of pelvic injury can be beneficial in accurately diagnosing the severity of injury and choosing appropriate treatment.

The application of the axial view projection of the S1 pedicel for sacroiliac screw.

BACKGROUND: The objective of this study was to position the iliosacral screws speedily, easily, and safely, we sought to delineate readily reproducible radiographic anatomic clues of the pedicel of S1 for the iliosacral screw placement. METHODS: We used eight normal adult pelvic specimens lying on the operation table in the prone position. First, the C-arm fluoroscope unit is positioned for the lateral view of the body of S1. We gradually changed the angle of the C-arm to ventral and cephalad. When a clear oval track image appears, we fix the angle of the C-arm. With the assistance of the C-arm projection, the starting point for the guide pin is centered on the oval track, and the orientation is adjusted. When the projection of the guide pin became a point inside of the oval track, the guide pin is inserted using battery-powered equipment. The accuracy and angle of pin placement is assessed using computed tomography scans in all cases. RESULTS: In all the pelves, the oval track has been successfully found, and the guide pins are accurately inserted using the sacral pedicel axial view. In the angular orientations by the computed tomography scan, the transverse plane inclination to the ventral of the guide pin is approximately 38.3 degrees +/- 1.9 degrees, and the frontal plane inclination to the cephalad is approximately 29.6 degrees +/- 2.0 degrees. CONCLUSION: The sacral pedicel axial view projection is a optimal radiographic technique for percutaneous placement of iliosacral screws in clinical practice. We can get the limpid axial view of pedicel of S1 to applicate this project method, which provides a speedier method with less radiation exposure for percutaneous placement of iliosacral screws.

Traction table-related complications in orthopaedic surgery.

Traction tables are used in numerous procedures about the hip and femur, including fracture fixation, hip arthroscopy, and less invasive arthroplasty. The use of a traction table is not without risks, however, and significant complications have been described, including injury to the perineal integument and soft tissues, neurologic impairment, and iatrogenic compartment syndrome of the well leg. The orthopaedic surgeon who uses a traction table for the surgical management of femur fracture must be familiar with the associated potential dangers and risks and must develop a plan to avoid traction table-associated complications, such as use of a radiolucent flat-top operating table for obese patients, adequate patient positioning, and the minimum possible surgical time.

Superior gluteal artery injury presenting as delayed onset shock.

Injury to the superior gluteal artery (SGA) is usually associated with acetabular fractures or posterior pelvic ring injuries. The diagnosis is suspected in cases of initial hemodynamic instability which is refractory to resuscitation. The initial presentation is often dramatic and is caused by direct injury to the artery at the time of traumatic impact. In these cases, patient management at most trauma centers follows a pre-arranged algorithm which decreases the likelihood of a missed diagnosis. Delayed arterial bleeding, however, is rare and potentially catastrophic since most algorithms are not designed to detect these infrequent occurrences. We present two such cases due to initial blunt buttock trauma combined with an anterior pelvic ring fracture and a L2 spine fracture which resulted in delayed massive bleeding from the SGA. Delayed arterial bleeding should be considered in late onset shock associated with pelvic or lumbar vertebrae body fractures or direct buttock injury. If active bleeding is suspected, urgent arteriography with embolization is the treatment of choice.

Absence of the complement regulatory molecule CD59a leads to exacerbated neuropathology after traumatic brain injury in mice.

BACKGROUND: Complement represents a crucial mediator of neuroinflammation and neurodegeneration after traumatic brain injury. The role of the terminal complement activation pathway, leading to generation of the membrane attack complex (MAC), has not been thoroughly investigated. CD59 is the major regulator of MAC formation and represents an essential protector from homologous cell injury after complement activation in the injured brain. METHODS: Mice deleted in the Cd59a gene (CD59a-/-) and wild-type littermates (n = 60) were subjected to focal closed head injury. Sham-operated (n = 60) and normal untreated mice (n = 14) served as negative controls. The posttraumatic neurological impairment was assessed for up to one week after trauma, using a standardized Neurological Severity Score (NSS). The extent of neuronal cell death was determined by serum levels of neuron-specific enolase (NSE) and by staining of brain tissue sections in TUNEL technique. The expression profiles of pro-apoptotic (Fas, FasL, Bax) and anti-apoptotic (Bcl-2) mediators were determined at the gene and protein level by real-time RT-PCR and Western blot, respectively. RESULTS: Clinically, the brain-injured CD59a-/- mice showed a significantly impaired neurological outcome within 7 days, as determined by a higher NSS, compared to wild-type controls. The NSE serum levels, an indirect marker of neuronal cell death, were significantly elevated in CD59a-/- mice at 4 h and 24 h after trauma, compared to wild-type littermates. At the tissue level, increased neuronal cell death and brain tissue destruction was detected by TUNEL histochemistry in CD59a-/- mice within 24 hours to 7 days after head trauma. The analysis of brain homogenates for potential mediators and regulators of cell death other than the complement MAC (Fas, FasL, Bax, Bcl-2) revealed no difference in gene expression and protein levels between CD59a-/- and wild-type mice. CONCLUSION: These data emphasize an important role of CD59 in mediating protection from secondary neuronal cell death and further underscore the key role of the terminal complement pathway in the pathophysiology of traumatic brain injury. The exact mechanisms of complement MAC-induced secondary neuronal cell death after head injury require further investigation.

Inhibition of complement C5a prevents breakdown of the blood-brain barrier and pituitary dysfunction in experimental sepsis.

INTRODUCTION: Septic encephalopathy secondary to a breakdown of the blood-brain barrier (BBB) is a known complication of sepsis. However, its pathophysiology remains unclear. The present study investigated the effect of complement C5a blockade in preventing BBB damage and pituitary dysfunction during experimental sepsis. METHODS: Using the standardised caecal ligation and puncture (CLP) model, Sprague-Dawley rats were treated with either neutralising anti-C5a antibody or pre-immune immunoglobulin (Ig) G as a placebo. Sham-operated animals served as internal controls. RESULTS: Placebo-treated septic rats showed severe BBB dysfunction within 24 hours, accompanied by a significant upregulation of pituitary C5a receptor and pro-inflammatory cytokine expression, although gene levels of growth hormone were significantly attenuated. The pathophysiological changes in placebo-treated septic rats were restored by administration of neutralising anti-C5a antibody to the normal levels of BBB and pituitary function seen in the sham-operated group. CONCLUSIONS: Collectively, the neutralisation of C5a greatly ameliorated pathophysiological changes associated with septic encephalopathy, implying a further rationale for the concept of pharmacological C5a inhibition in sepsis.

Bench-to-bedside review: Burn-induced cerebral inflammation--a neglected entity?

Severe burn injury remains a major burden on patients and healthcare systems. Following severe burns, the injured tissues mount a local inflammatory response aiming to restore homeostasis. With excessive burn load, the immune response becomes disproportionate and patients may develop an overshooting systemic inflammatory response, compromising multiple physiological barriers in the lung, kidney, liver, and brain. If the blood-brain barrier is breached, systemic inflammatory molecules and phagocytes readily enter the brain and activate sessile cells of the central nervous system. Copious amounts of reactive oxygen species, reactive nitrogen species, proteases, cytokines/chemokines, and complement proteins are being released by these inflammatory cells, resulting in additional neuronal damage and life-threatening cerebral edema. Despite the correlation between cerebral complications in severe burn victims with mortality, burn-induced neuroinflammation continues to fly under the radar as an underestimated entity in the critically ill burn patient. In this paper, we illustrate the molecular events leading to blood-brain barrier breakdown, with a focus on the subsequent neuroinflammatory changes leading to cerebral edema in patients with severe burns.

Safety and efficacy of damage control external fixation versus early definitive stabilization for femoral shaft fractures in the multiple-injured patient.

BACKGROUND: Optimal timing and treatment of patients with concomitant head, thoracic, or abdominal injury and femoral shaft fracture remain controversial. This study examines acute patient outcomes associated with early total care with intramedullary nailing (ETC group) versus damage control external fixation (DCO group) for multiple-injured patients with femoral shaft fractures. We propose DCO as a safe initial treatment for the multiple-injured patient with femur shaft fractures. METHODS: This study was a retrospective review of the trauma registry and multisystem organ failure registry data at a Level I trauma center. Two cohorts were identified to compare multiple-injured patients with femoral shaft fractures treated with early total care and damage control orthopaedic surgery. Primary outcome measures included mortality, pulmonary complications (adult respiratory distress syndrome [ARDS] score), transfusion requirements, and multiple organ failure (MOF score). Operative time, estimated blood loss, intensive care unit length of stay (LOS), and hospital length of stay (LOS) were also compared. RESULTS: During the study period, 462 patients with 481 femoral shaft fractures were identified. Of 462 patients with femoral shaft fractures, 97 met the inclusion criteria (42 ETC and 55 DCO). The DCO group had a significantly shorter operative time (22 minutes vs. 125 minutes) and less estimated blood loss from their operative procedure (37 mL vs. 330 mL). There was no significant difference between the groups for ARDS, lung scores, MOF, MOF score, intensive care unit LOS, or hospital LOS. CONCLUSION: Fracture fixation method did not have an impact on the incidence of systemic complications in multiple-injured patients with femoral shaft fractures. Although minimal differences were noted between DCO and ETC groups regarding systemic complications, DCO is a safer initial approach, significantly decreasing the initial operative exposure and blood loss.

Management of hemorrhage in life-threatening pelvic fracture.

Emergent life-saving treatment is required for high-energy pelvic fracture with associated hemorrhage and hemodynamic instability. Advances in prehospital, interventional, surgical, and critical care have led to increased survival rates. Pelvic binders have largely replaced military antishock trousers. The availability and precision of interventional angiography have expanded considerably. External pelvic fixation can be rapidly applied, often reduces the pelvic volume, and provides temporary fracture stabilization. Pelvic packing, popularized in Europe, is now used in certain centers in North America. The use of standardized treatment algorithms may improve decision making and patient survival rates. Active involvement of an experienced orthopaedic surgeon in the evaluation and care of these critically injured patients is essential.

Posttraumatic stress disorder and depression negatively impact general health status after hand injury.

PURPOSE: To estimate the prevalence of posttraumatic stress disorder (PTSD) and depression among hand-injured patients and assess the impact of these disorders on general health status. METHODS: A total of 106 adult hand-injured patients (40 women, 66 men) with a mean age of 42 years (range, 18-79 years) participated. Patients with a chronic mental illness or cognitive impairment were excluded. Psychological status was assessed using the Revised Civilian Mississippi Scale for PTSD and the Beck Depression Inventory. General health status was evaluated with the Short Form-36 health survey (SF-36). We obtained demographics and injury characteristics from the patient medical records. RESULTS: Prominent mechanisms of injury included a fall (n = 38), traffic-related injuries (n = 14), machine versus operator (n = 8), gunshot wounds (n = 6), and assault (n = 6). Using the screening questionnaires, 32 persons qualified for PTSD and 19 for depression. Sixteen patients met the criteria for both PTSD and depression. The association between PTSD and depression was significant (p < .01). Patients with PTSD had significantly lower scores than those who did not endorse items consistent with PTSD or depression on the SF-36 subscales of role-emotional (p < .01), body pain (p = .013), social function (p = .028), and mental health (p < .01). We found no significant differences between groups for the subscales of role-physical (p = .289), general health (p = .147), vitality (p = .496), and physical functioning (p = .476). Patients who had concurrent PTSD and depression had significantly lower scores than patients who had neither PTSD nor depression on all subscales (p < .05 for all) except role-physical (p = .135). We found significant negative correlations between Beck Depression Inventory scores and all of the SF-36 subscales (p < .05 for all). CONCLUSIONS: In this study, nearly one third of hand-injured patients met diagnostic criteria for PTSD, depression, or both, according to the thresholds of the instruments used to measure these psychological aspects of illness. PTSD and depression had a negative effect on general health status after hand injury. It may be important to consider psychological status when caring for patients with hand injuries.

Pharmacology of traumatic brain injury: where is the "golden bullet"?

Traumatic brain injury (TBI) represents a major health care problem and a significant socioeconomic challenge worldwide. In the United States alone, approximately 1.5 million patients are affected each year, and the mortality of severe TBI remains as high as 35%-40%. These statistics underline the urgent need for efficient treatment modalities to improve posttraumatic morbidity and mortality. Despite advances in basic and clinical research as well as improved neurological intensive care in recent years, no specific pharmacological therapy for TBI is available that would improve the outcome of these patients. Understanding of the cellular and molecular mechanisms underlying the pathophysiological events after TBI has resulted in the identification of new potential therapeutic targets. Nevertheless, the extrapolation from basic research data to clinical application in TBI patients has invariably failed, and results from prospective clinical trials are disappointing. We review the published prospective clinical trials on pharmacological treatment modalities for TBI patients and outline future promising therapeutic avenues in the field.

Treatment of distal femur and proximal tibia fractures with external fixation followed by planned conversion to internal fixation.

PURPOSE: To evaluate healing rates and complications in patients treated with temporary external fixation (EF) and subsequent open reduction and internal fixation (ORIF) for high-energy distal femur or proximal tibia fractures. METHODS: Retrospective analysis of prospectively collected data 1999 to 2005. Demographic data and injury severity score were obtained from medical records. Factors reviewed included perioperative complications (nonunion, postoperative infection, loss of fixation) and time to radiographic and clinical union. RESULTS: Forty-seven patients with 16 distal femur and 36 proximal tibia fractures were treated using temporary EF. Patients subsequently underwent ORIF (mean time from EF to ORIF = 5 days, range 1-23 days). Thirty-five fractures were open (Gustilo I = 8, II = 6, IIIA = 3, IIIB = 13, IIIC = 5) and 17 closed. Forty patients with 44 fractures reached 1-year follow-up. Of these, 36 patients with 40 (91%) fractures had healed both radiographically and clinically. The mean postoperative follow-up time was 14 months (range 3-68). Eight (16%) deep infections occurred, all in open fractures (Gustilo I = 2, IIIB = 3, IIIC = 3), with one patient requiring above knee amputation. Other complications included one hematoma, two malunions, one fixation failure, and one pin site infection. One patient died as a result of a stroke. CONCLUSIONS AND SIGNIFICANCE: Temporary bridging EF offers the advantage of early soft tissue and bone stabilization without the potential local risks of immediate ORIF in severely injured soft tissues, or the potential systemic risks in a severely traumatized patient. The 16% infection rate in this study, all occurring in open fractures, falls within the reported range for grade III open fractures (15%-20%). We conclude that the initial treatment of high-energy periarticular knee fractures with bridging EF, followed by planned conversion to internal fixation is a safe option in patients who are unsuitable for initial definitive surgery.

Serum titanium levels in individuals undergoing intramedullary femoral nailing with a titanium implant.

BACKGROUND: Many patients request nail extraction or question the long-term effects of hardware retention. Systemic titanium degradation products may influence the timing of such decisions. The orthopedic literature provides no data regarding systemic titanium in patients undergoing intramedullary nail fixation with titanium implants. The purpose of this study was to determine the systemic level of serum titanium in patients who had undergone femoral nailing. METHODS: Patients who underwent antegrade locked femoral nailing utilizing a reamed technique with a titanium implant were eligible to participate. Eight patients were recruited for each of four time points: 6 weeks, 3 months, 6 months, and 1 year. Blood samples were collected from each subject. Serum titanium levels were analyzed through inductively coupled plasma/mass spectrometry (ELAN DRC II, Perkin Elmer, SCIEX, Inc, Shelton, CT). Test sensitivity was 0.2 microg/L. Normal serum titanium levels are <150 microg/L. RESULTS: Thirty-two patients were enrolled. The study group included 10 women and 22 men with average age of 32 (range 19-63) years. The most common fracture pattern was 32-A3 (n = 12), followed by 32-B2 (n = 9). No patients showed an elevated serum titanium level. Mean titanium levels were 49.38, 58.25, 49.38, and 50.63 microg/L at 6 weeks, 3 months, 6 months, and 12 months cohorts, respectively. No statistically significant differences were found (p = 0.207). CONCLUSIONS: Standard intramedullary nail fixation of femur fractures did not result in elevated levels of serum titanium in the first year after surgery. Differences in serum titanium did not differ significantly across time since implantation.

Retrograde femoral nailing: an understanding of the intercondylar insertion site.

BACKGROUND: : The intercondylar starting site for retrograde femoral nailing has been selected to avoid damage to the articular weight-bearing surface. This starting point assumes that implants will adapt to the femoral radius of curvature. Implant-femur radius mismatch may result in postoperative fracture angulations, translation, or increase in hoop stress. METHODS: : Twenty cadaveric femurs were analyzed. The posterior cruciate ligament (PCL) was preserved. Two different femoral nails were analyzed. After creating an osteotomy at the superior level of the lesser trochanter, a cannulated nail was inserted to the level of the articular surface of the distal femur. A pointed guide wire was advanced through the nail and driven through the articular surface of the distal femur. The exact location of the guide wire exiting the articular surface was anatomically and radiographically determined. RESULTS: : The mean anterior distance of the wire to the PCL was 20.4 mm for the ACE nail and 13.9 mm for the Synthes Femoral Nail (SFN). A Student's t test showed a significant difference between the two implants (p = 0.0002). The mean medial distance of the guide wire exit compared with the PCL was 4.2 mm for the ACE and 4.1 mm for the SFN nail and showed no significant difference. CONCLUSIONS: : The tested nails require a more anterior insertion site than what has been described to match the femur curvature. Of the two nail designs evaluated, the SFN was more compatible with the currently recommended starting point.