The evolution of 3D imaging in orthopedic trauma care.

Three-dimensional (3D) imaging can enhance trauma care by allowing better evaluation of bony detail and implant position compared to conventional fluoroscopy or x­ray. Intraoperative 3D imaging further improves this evaluation by allowing any necessary revisions to be made in the operating room prior to the patient emerging from anesthesia. This revision, if necessary, better achieves the surgical goals and alleviates the stressful situation of obtaining postoperative 3D imaging, where the benefit of revision must be balanced against the cost and risk of returning to the operating room. Improved image volume, resolution, and software capability have allowed surgeons to obtain high-quality, wide field views of bony anatomy that can include the uninjured side as a comparison. In this paper, the evolution of intraoperative 3D imaging over the past 25 years is discussed.

[The evolution of 3D imaging in orthopedic trauma care. German version]. / Entwicklung der 3­D-Bildgebung in der Versorgung orthopädischer Verletzungen.

Three-dimensional (3D) imaging can enhance trauma care by allowing better evaluation of bony detail and implant position compared to conventional fluoroscopy or x­ray. Intraoperative 3D imaging further improves this evaluation by allowing any necessary revisions to be made in the operating room prior to the patient emerging from anesthesia. This revision, if necessary, better achieves the surgical goals and alleviates the stressful situation of obtaining postoperative 3D imaging, where the benefit of revision must be balanced against the cost and risk of returning to the operating room. Improved image volume, resolution, and software capability have allowed surgeons to obtain high quality, wide field views of bony anatomy that can include the uninjured side as a comparison. In this paper, the evolution of intraoperative 3D imaging over the past 25 years is discussed.

Pulmonary haptoglobin and CD163 are functional immunoregulatory elements in the human lung.

BACKGROUND: The acute-phase protein haptoglobin (Hp) and its receptor CD163 serve as immunomodulators and possess anti-inflammatory besides antioxidant functions. OBJECTIVES: To further understand the role of the recently described pulmonary Hp (pHp) and its receptor CD163 in case of inflammation and infection, pHp and CD163 were investigated on mRNA and protein level to gain insight into the cellular events taking place upon stimulation with the inflammatory mediators LPS, Pam3, cytokine IL-6 and dexamethasone, and upon infection with respiratory pathogens (Haemophilus influenzae, Streptococcuspneumoniae and Chlamydia pneumoniae) by use of a human ex vivo tissue culture model and cell cultures of A549 and alveolar epithelial cells type II. In addition, pHp and CD163 expression in COPD and sarcoidosis was assessed. METHODS: We conducted experiments using 942 ex vivo cultured lung samples applying immunohistochemistry, immunocytochemistry, in situ hybridization, immunofluorescence, real-time PCR, RT-PCR, slot and Western immunoblot analyses with tissue lysates and culture supernatants as well as ELISA and cytometric bead array analyses. RESULTS: This study describes for the first time the expression, regulation and secretion of pHp and its receptor CD163 in the human lung. The release of soluble mediators from A549 cell line and human monocyte-derived macrophages was observed indicating that Hp differentially activates the release of soluble mediators and major chemoattractants. CONCLUSIONS: The findings indicate a native function of pHp and CD163 as functional pulmonary defense elements due to local expression, regulation and secretion during lung infection and as part of the inflammatory immune response of the respiratory system.

Tumors in the lung--morphologic features and the challenge of integrating biomarker signatures into diagnostics.

In the last decade, pathologic approaches concerning diagnosis and treatment of lung carcinomas have increasingly moved towards the implementation of molecular methods into the process of decision. In this study, an overview is given referring to the variety of tumors in the lung including common primary lung neoplasms and secondary tumors, and a modus operandi is presented which integrates immunology as well as molecular pathology within the process of finding correct diagnoses. Besides the conventional and approved methods and techniques leading to appropriate treatment including so-called targeted therapies, pathologist's work meanwhile depends on both histologic and molecular results. Since molecular techniques have increasingly entered the field of routine diagnostics, challenges and possibilities have changed and are still rapidly developing. The proceeding integration of molecular-biologic investigations into the process of diagnosing has changed the nature of diagnostics and will continuously grow in the near future. Only by obtaining a proper diagnosis, the optimal treatment of a patient can be assured, whereupon the knowledge of gene mutations and/or altered protein expression is crucial. By identifying those novel molecular target structures, the therapeutic spectrum is tremendously enlarged and will finally improve the patient's prognosis by personalized targeted therapies.

Realization and verification of three-dimensional conformal radiotherapy with modulated fields.

PURPOSE: We describe the experimental demonstration of the delivery of a three-dimensional conformal radiotherapy dose distribution using in-field modulation of nine fixed-gantry fields. METHODS AND MATERIALS: Two-dimensional in-field modulation profiles, varying from field to field, were realized by quasi-dynamic multileaf collimation using the prototype of a commercially available multileaf collimator installed on a medical linear accelerator. The profiles were calculated to deliver an optimal dose distribution for a patient with a prostate carcinoma. The target volume surface was invaginated and bifurcated. The calculated dose distribution was delivered to a homogeneous polystyrene phantom consisting of 1 cm thick slices that were cut to match the patient's outer contour. Seven therapy verification films were placed between the phantom slices. RESULTS: Analysis of the films revealed a degree of conformation of the high-dose region to the target shape that would not be possible with unmodulated conformal therapy. However, small observed spatial displacements of the dose distribution confirm the need for very accurate positioning. CONCLUSIONS: It is feasible to deliver clinically relevant, three-dimensional dose distributions that conform to invaginated and bifurcated target volumes using fields modulated by multileaf collimators.

X-ray field compensation with multileaf collimators.

PURPOSE: It has been proposed that conformal therapy can be carried out with static ports that are each individually compensated to deliver an optimal total dose distribution. If this proposal is to be implemented, one must have a means of compensating or modulating the fluence distributions within the boundaries of individual treatment fields. A theory was developed and implemented to achieve this goal. METHODS AND MATERIALS: The theory allowed creation of a leaf-setting sequence for a desired level of field-modulation precision. This method of beam modulation was experimentally verified using radiographic film to integrate the dose delivered by the sequence of discrete static multileaf collimator-defined subfields. RESULTS: Beam profiles were generated that matched the planned beam profiles to within the specified degree of precision. CONCLUSION: This methodology is a candidate for implementation of inverse planning for conformal therapy.

Surface and percentage depth doses for secondary blocking using a multileaf collimator and cerrobend-alloy blocks.

Percentage depth doses from the surface to a depth of 30 cm have been measured for a number of square fields using 6 MV and 15 MV X-rays as part of the commissioning procedure for a commercially available MLC. Factors such as changing SSD, presence of a secondary blocking tray in the beam, and radiation transmission between the MLC leaves were investigated.

Flatness characteristics for diagonal scans from Varian and Siemens linear accelerators.

The advent of 3D treatment planning systems whose algorithms utilize diagonal scan data to perform dose calculations has made the collection of diagonal profile data essential. Manufacturers' specifications (MS) on beam flatness and symmetry apply to both the radial and transverse axes of all square field sizes from 10 X 10 cm2 to the largest field available. Beam profile measurements were obtained for both diagonal axes over a range of field sizes and depths for two units, a Varian 2100C and a Siemens KD. In this note the International Electrotechnical Commission (IEC) flatness definition was used to characterize the diagonal flatness of each beam.

Tacrolimus-based triple-drug immunosuppression minimizes serum lipid elevations in pediatric cardiac transplant recipients.

BACKGROUND: Immunosuppression with corticosteroids and cyclosporine has been associated with hyperlipidemia, a risk factor for post-transplant coronary artery disease. The recent development of tacrolimus has created an alternative to cyclosporine-based triple drug immunotherapy. One potential benefit that has been reported in patients receiving tacrolimus is a minimization of elevation of both total and LDL cholesterol, compared to those increases observed in patients receiving cyclosporine-based immunosuppression. It is unclear in previous studies whether this beneficial effect is related to tacrolimus directly or to its corticosteroid sparing potential. To study this relationship, we compared lipid profiles from pediatric cardiac transplant recipients treated with corticosteroids, and either cyclosporine or tacrolimus. METHODS: The study group consisted of 23 patients (mean age = 12.3 years) with pre-transplant and serial post-transplant determinations of total cholesterol, LDL, HDL, and triglycerides. Patients were separated into 4 study groups, defined by immunosuppressive regimen (cyclosporine vs. tacrolimus) and prednisone dose (>0.10 mg/kg/day vs. < or =0.10 mg/kg/day). RESULTS: Patients who received cyclosporine and higher doses of prednisone experienced a mean 74 mg/dl increase from baseline in total cholesterol (p = .0001). None of the other 3 treatment groups demonstrated a statistically significant elevation. Similar trends were observed in LDL and triglyceride alterations between the 4 study groups. Interestingly, patients treated with tacrolimus and higher doses of prednisone demonstrated a significant rise in HDL from baseline (p = .0001), although those who received cyclosporine and higher dose prednisone failed to exhibit this rise. CONCLUSION: The minimal degree of lipid alteration seen in patients receiving tacrolimus and higher doses of prednisone indicates that this effect was not solely based upon the steroid-sparing properties of tacrolimus therapy. The data also suggests a possible synergistic effect between cyclosporine and higher doses of prednisone on hyperlipidemia. Therefore, in pediatric patients requiring higher corticosteroid doses late after transplantation, use of tacrolimus rather than cyclosporine may lead to more favorable lipid profiles and help minimize the risk of post-transplant coronary arteriopathy.

Safety and efficacy of pravastatin therapy for the prevention of hyperlipidemia in pediatric and adolescent cardiac transplant recipients.

BACKGROUND: Hyperlipidemia is common after cardiac transplantation and it is a risk factor for post-transplantation coronary artery disease. Immunosuppression with corticosteroids and cyclosporine has been associated with hyperlipidemia. Pravastatin, a HMG-CoA reductase inhibitor, has been shown to be effective and safe for cholesterol reduction in adult heart transplant recipients. To our knowledge the safety and efficacy of pravastatin therapy in pediatric and adolescent heart transplant populations have not been previously analyzed. Therefore, we evaluated lipid profiles, liver transaminases, rejection data, and possible side effects in pediatric and adolescent cardiac transplant recipients treated with pravastatin. METHODS: The study group consisted of 40 cardiac transplant recipients 10 to 21 years old (mean age 16.9 years). Twenty-two patients received pravastatin in addition to an immunosuppressive regimen of either cyclosporine or tacrolimus, azathioprine or mycophenolate mofetil, and prednisone. Serial determinations of total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein, and triglycerides were available for all pravastatin-treated patients. Pre-treatment lipid values and hepatic transaminases were compared with those measured after therapy with pravastatin. Comparison of pravastatin-induced lipid reduction between groups treated with cyclosporine vs tacrolimus was also made. RESULTS: Patients receiving pravastatin experienced a mean 32 mg/dl decrease in TC (p < 0.005) and a mean 31 mg/dl decrease in LDL (p < 0.005), regardless of their immunosuppressive regimen. No statistical differences occurred in the magnitude of mean lipid reduction induced by pravastatin between the groups treated with cyclosporine vs tacrolimus. No significant changes in hepatic transaminase levels were noted, and no clinical evidence of pravastatin-induced myositis occurred in any subjects. CONCLUSION: Pravastatin therapy is effective and safe when used in pediatric and adolescent cardiac transplant recipients. Although the pravastatin-induced reduction in TC and LDL was more pronounced in patients receiving cyclosporine, the reduction was not statistically different from that in the tacrolimus group. No evidence of hepatic dysfunction or rhabdomyolysis in patients treated with pravastatin was noted. Long-term studies are required to evaluate the effect of pravastatin therapy on the incidence of accelerated coronary atherosclerosis in this population.

Inability to obtain formal informed consent in the face of a standard surgical indication.

A thirty-eight-year-old intoxicated man was admitted to the surgical trauma service following a single motor-vehicle accident. He had a severe closed head injury, bilateral pulmonary contusions, a fracture-dislocation of the right acetabulum, and an open injury of the right knee joint. The acetabular fracture pattern was an associated both-column fracture with the femoral head dislocated into a widely displaced posterior-column fracture line. The treating physicians agreed that it would be in the patient's best interest to take him to the operating room for emergent debridement and irrigation of his knee wound. At surgery, the patient also underwent attempted closed reduction of the acetabular fracture and placement of a skeletal traction pin. Radiographs obtained with the patient in traction showed reduction of the femoral head beneath a displaced superior dome fragment, but there remained a 12-mm gap in the posterior column, greater than 3 mm of step incongruity, and a large articular fragment entrapped in the anterior aspect of the hip joint. The patient remained intubated and sedated for several days. Upon weaning from the ventilator, it became evident that his head injury would prevent him from being able to give informed consent in the foreseeable future. The patient's family members refused to become involved with his care or medical decision-making, as he had become completely estranged from them as a result of his chronic alcohol abuse. Further delay in surgical treatment for the acetabular fracture would be associated with greater difficulty in obtaining an anatomic reduction, the potential for additional articular damage to the femoral head, and an increased risk of surgical complications. The question that arises is whether it is in the patient's best interest for the surgeon to proceed with open reduction and internal fixation of the acetabular fracture without having had the opportunity to fully inform him of the treatment options or the risks associated with an extensive surgical exposure.

The impact of ankle radiographs on the diagnosis and management of acute ankle injuries.

RATIONALE AND OBJECTIVES: We assessed the impact of ankle radiographs on referring physicians' diagnoses and treatment of acute ankle injuries. METHODS: Twenty emergency department physicians prospectively completed questionnaires before and after radiography on 101 patients with acute trauma receiving ankle radiographs. The questionnaires asked physicians to estimate the probability (0-100%) of their most likely diagnosis before and after receiving the radiographic information. We also asked their anticipated and final treatment plans. We calculated the mean gain in diagnostic confidence percentage and the proportion of patients with changed initial diagnoses or anticipated management. RESULTS: The mean gain in diagnostic certainty from ankle radiographs was 34% (95% confidence interval [CI] = 28-40%). Ankle radiographs changed physicians' initial diagnoses in 37% (95% CI = 28-47%) of the patients. Immediate clinical management changed in 30% (95% CI = 22-40%) of the patients. CONCLUSION: Plain ankle radiographs have considerable impact on referring physicians' diagnoses and treatment of acute ankle trauma.

Stress fracture of the femoral neck in a long distance runner: biomechanical aspects.

With the rising public interest in physical fitness, emergency physicians are seeing an increasing number of stress fractures. Early diagnosis, followed by conservative management, allowed a long-distance runner with a compression type stress fracture of the femoral neck to return to running. The biomechanical cause of this injury may be related to erosion of the sole of the running shoe that reduced its shock absorption and increased the potential for injury.

A trend analysis of the in vivo quadriceps femoris angle-specific torque-velocity relationship.

To adequately assess isokinetic human muscle performance, it is important for clinicians to understand how the muscle functions across a range of velocities. Thus, the purpose of this study was to re-examine the in vivo quadriceps torque-velocity relationship using trend analysis. Twelve uninjured university-age females performed three concentric and eccentric contractions at velocities of 0, 25, 50, 75, 100, 125, 150, 175, and 200 degrees/sec on the Kin-Com isokinetic dynamometer. A trend analysis was performed on the angle-specific torques at 30, 60, and 75 degrees of knee flexion. The results indicated that the concentric and eccentric relationships at 30 degrees and the concentric relationship at 60 degrees were represented by a third-order polynomial, and a linear relationship was found for concentric contractions at 75 degrees. There were no significant trends for the eccentric relationship at 60 and 75 degrees, suggesting that they were best described by the grand mean. These results suggest that muscular torque production varies across velocities and contraction modes and that this relationship varies depending on the joint angle of torque measurement.

Identification of tibial stress fractures using therapeutic continuous ultrasound.

STUDY DESIGN: One-group discriminant analysis. OBJECTIVE: To determine whether 1 MHz of continuous ultrasound can identify tibial stress fractures in subjects. BACKGROUND: Stress fractures can lead to loss of function or to more serious nonunion fractures. Early diagnosis is important to reduce the risk of further injury and to assure a safe return to activity. Therapeutic ultrasound has been reported to be an accessible, less expensive alternative in diagnosing stress fractures compared with other diagnostic techniques. METHODS AND MEASURES: Twenty-six subjects (12 men, 20.33 +/- 1.37 years; 14 women, 20.78 +/- 3.8 years) with unilateral tibia pain for less than 2 weeks volunteered to participate in the study. Continuous, 1 MHz ultrasound was applied to the uninvolved and involved tibias at 7 increasing intensities for 30 seconds each. Subjects completed a visual analog scale after the application of each intensity to assess the pain response to ultrasound. Results from the visual analog scale were compared to magnetic resonance imaging (MRI) findings to determine if continuous ultrasound could predict whether subjects had a normal MRI, increased bone remodeling, or advanced bone remodeling consistent with a stress fracture. RESULTS: Discriminant analysis on the visual analog scale correctly classified subjects into 1 of 3 clinical classification groups in 42.31% of the cases. None of the subjects found to have a stress fracture by MRI were correctly identified by continuous ultrasound. This resulted in a predicted sensitivity of 0% and a predicted specificity of 100%. CONCLUSIONS: A protocol using visual analog scores after the application of 1 MHz continuous ultrasound is not sensitive for identifying subjects with tibial stress fractures.

Metacarpophalangeal and proximal interphalangeal joint injuries of the hand, including the thumb.

There is no cookbook approach to the treatment of a swollen finger or thumb. Different injury patterns may require different types of immobilization and different periods of abstinence from participation. Certain articular fractures and collateral ligament injuries have better results when treated with primary surgical intervention. It is only through accurate evaluation and adequate treatment that we may prevent long-term disability secondary to articular injuries of the fingers and thumb.

Effect of ACL Reconstruction and Tibial Rotation on Anterior Knee Laxity.

The anterior cruciate ligament (ACL) is the primary restraint to anterior translation of the tibia on the femur. Research suggests that resistance to anterior translation changes as the tibia is rotated internally and externally. This study assessed the degree to which ACL reconstruction and tibial rotation affects anterior knee laxity. Nine subjects with ACL lesions and functional instabilities participated in the study. Subjects were measured 1 to 10 days before surgery and 6 to 8 months after ACL reconstruction using the KT-1000 knee arthrometer. A mechanical leg stabilizer was used to assess anterior translation at 20 degrees of knee flexion in three positions: internal rotation of 15 degrees , neutral, and external rotation of 15 degrees . Subjects were measured at 89 and 67 N of anterior force. Data were analyzed with a three-factor (test x position x force) repeated measures ANOVA. Following surgery, reduction in laxity (mm) for the three positions (internal rotation, neutral, and external rotation) was 1.9, 2.8, and 3.4, respectively, at 89 N and 1.5, 2.0, and 2.6, respectively, at 67 N. The degree of reduction in laxity (presurgery to postsurgery) was dependent upon rotation and force, and was greatest in external rotation and least in internal rotation pre- to postsurgery. We concluded that ACL reconstruction using a patellar tendon graft significantly decreased anterior tibial translation at all three positions, but a greater amount of reduction was observed postsurgically at the externally rotated position. This supports the theory that mechanical blocks and secondary restraints such as a taut mid-third of the iliotibial tract may interfere with clinical laxity tests in some positions of tibial rotation. Fixing the tibia in an externally rotated position may decrease the effect of secondary restraints and improve sensitivity in testing for ACL laxity.

A 22-year-old woman with chronic, mild, intermittent knee pain.

The following case is presented to illustrate the roentgenographic and clinical findings of a condition of interest to orthopedic surgeons. The initial history, physical findings, and roentgenographic examination are found on the first page. The final clinical and roentgenographic diagnosis is presented on the following page.