Investigation of primary cell-biomaterial interactions using silver nitrate staining of nucleolar organising regions

The quantification of silver nitrate staining of nucleolar organising regions (AgNORs) within the nucleus of the cell has been shown to give a relative measure of the metabolic activity of the cell. In the present study, silver nitrate staining was utilised to identify metabolic variations in cells cultured on different surfaces and compared with proliferative activity assessed using bromodeoxyuridine (BrdU) uptake. Primary osteoblast and periosteal cells, isolated from the calvaria of neonate rats, were cultured on tissue culture-grade (TCPS) and bacteriological-grade (BACPS) polystyrene petri dishes for 3, 5, 7 and 9 days (silver nitrate) or 14 days (BrdU). The phenotype of the cells was examined using RT-PCR of the mRNA for osteocalcin, collagen 1a, alkaline phosphatase and osteopontin. The number and area of AgNORs and the proportion of BrdU positive cells were statistically different in cells cultured on TCPS compared with BACPS at each culture period tested. The results suggest that the metabolic activity and proliferation of cells were affected by the substrate which they colonise.

Changing patterns of pediatric pelvic fractures with skeletal maturation: implications for classification and management

Orthopaedic traumatologists have recognized the unique fracture patterns and injury constellations of pediatric pelvic fractures. However, an understanding of the effect of advancing skeletal maturation is needed to avoid applying adult classifications and management. The authors determined how pelvic fracture patterns and management change with advancing skeletal maturity. At their pediatric trauma center, they identified 166 consecutive pelvic fractures. Eighty percent of patients had plain radiographs adequate to evaluate the triradiate cartilage. Physes were scored as open, narrowed, or closed. The Risser sign, fracture pattern, survival after injury, and need for open reduction and internal fixation were recorded. Ninety-seven patients (mean age 5.7 years) had an open triradiate or an "immature pelvis." Thirty-two patients (mean age 14 years) had a closed triradiate cartilage or a "mature pelvis." The immature group had a higher propensity for isolated pubic rami and iliac wing fractures. The mature group had a higher predilection for acetabular fractures and pubic or sacroiliac diastasis. All patients requiring open reduction and internal fixation had a mature pelvis. The incidences of specific pelvic fracture patterns between the two groups were statistically different. Management of fractures to the immature pelvis should focus on associated injuries. Once the triradiate cartilage has closed, adult pelvic fracture classifications and management principles should be used.

Surgical treatment of congenital kyphosis

STUDY DESIGN

In this study, 26 cases of congenital kyphosis and kyphoscoliosis treated surgically were retrospectively reviewed.

OBJECTIVE

To assess the clinical outcomes and surgical indications for posterior only versus anteroposterior surgery in the child.

SUMMARY OF BACKGROUND DATA

Congenital kyphosis usually is progressive without surgical intervention. Current recommended treatment includes posterior arthrodesis for deformities of less than 50 degrees to 60 degrees, and anterior release or decompression, anterior fusion, and posterior instrumented arthrodesis for large deformities and cord compression.

METHODS

Cases involving myelodysplasia, spinal dysgenesis, and skeletal dysplasia were excluded from the study. Kyphoscoliosis was included if the kyphotic deformity was greater than the scoliotic deformity. Patients were grouped by age and surgical technique. The patients in group P1 underwent posterior arthrodesis at an age younger than 3 years, and those in group P2 underwent the procedure at an age older than 3 years. The patients in group AP1 underwent anterior and posterior procedures at an age younger than 3 years, and those in group AP2 underwent the procedures at an age older than 3 years. The preoperative deformity, complications, and postoperative deformity correction were analyzed. There were nine Type 1 (failure of formation), nine Type 2 (failure of segmentation), and eight Type 3 (mixed) deformities. Four patients had associated spinal dysraphism. Three patients with Type 1 deformities had clinical or radiographic evidence of cord compression.

RESULTS

In Group P1, five patients at an average age of 16 months underwent posterior arthrodesis alone for an average kyphotic deformity of 49 degrees. The immediate postoperative correction improved over a period of 6 years and 9 months by an additional 10 degrees, resulting in a final deformity of 26 degrees. Pseudarthrosis developed in two patients, requiring fusion mass augmentation or anterior arthrodesis. Neither patient was instrumented. In Group P2, five patients at an average age of 13 years and 7 months underwent posterior arthrodesis with instrumentation for kyphotic deformity of 59 degrees. Approximately 30 degrees of intraoperative correction was achieved safely using compression instrumentation and positioning. No further correction occurred with growth. The final residual kyphotic deformity was 29 degrees after a follow-up period of 4 years and 5 months. In Group AP1, seven patients underwent anterior release or vertebra resection for deformity correction and posterior arthrodesis for an average kyphotic deformity of 48 degrees at the age of 16 months. There were no iatrogenic neurologic injuries. The final residual kyphotic deformity was 22 degrees after a follow-up period of 6 years and 3 months. In Group AP2, nine patients underwent anterior release or decompression with posterior arthrodesis for kyphotic deformity of 77 degrees at the age of 11 years and 6 months. The deformity was corrected to 37 degrees, with no significant loss over a follow-up period of 5 years and 2 months. There were two postoperative neurologic complications.

CONCLUSIONS

After reviewing their experience, the authors made the following observations: 1) The pseudarthrosis rate was low even without routine augmentation of fusion mass if instrumentation was used; 2) gradual correction of kyphosis may occur with growth in patients younger than 3 years with Types 2 and 3 deformities after posterior fusion, but appears to be unpredictable; 3) the risk of neurologic injury with anterior and posterior fusion for kyphotic deformity was associated with greater age, more severe deformity, and preexisting spinal cord compromise.

Overlapping recognition determinants within the ssrA degradation tag allow modulation of proteolysis

The ssrA tag, an 11-aa peptide added to the C terminus of proteins stalled during translation, targets proteins for degradation by ClpXP and ClpAP. Mutational analysis of the ssrA tag reveals independent, but overlapping determinants for its interactions with ClpX, ClpA, and SspB, a specificity-enhancing factor for ClpX. ClpX interacts with residues 9-11 at the C terminus of the tag, whereas ClpA recognizes positions 8-10 in addition to residues 1-2 at the N terminus. SspB interacts with residues 1-4 and 7, N-terminal to the ClpX-binding determinants, but overlapping the ClpA determinants. As a result, SspB and ClpX work together to recognize ssrA-tagged substrates efficiently, whereas SspB inhibits recognition of these substrates by ClpA. Thus, dissection of the recognition signals within the ssrA tag provides insight into how multiple proteins function in concert to modulate proteolysis.

Care for children with special health care needs in a managed care system: a patient satisfaction survey

In 1994 the government of Puerto Rico adopted a capitated managed health care system for the medically indigent. The new law has been implemented in most municipalities. A survey of children with special health care needs treated at a tertiary pediatric center under the capitated managed care system and the prior non-capitated system was analyzed using the Consumer Assessments of Health Plan Survey (CHAPS) instrument. One third of the patients who were under the new capitated managed care system were not satisfied with the medial care they were receiving. The parents of children with multidisciplinary conditions found it much more difficult to access care at the tertiary center. It took parents two years to learn to navigate within the capitated managed care system. Studies to measure outcome and health quality of children with special health care needs in capitated managed health care programs must be developed to learn how the potential benefits of managed care can be maximized and the potential harms minimized. The purpose of this study was to analyze the accessibility and satisfaction of caretakers of children with special health care needs under a capitated managed health care system.

Analysis of the cause, classification, and associated injuries of 166 consecutive pediatric pelvic fractures

SUMMARY

Pediatric pelvic fractures are serious injuries. Anatomical differences exist between pediatric and adult populations, leading to different causes and rates of death, fracture patterns, and associated injuries. This study is the largest consecutive series of pediatric pelvic fractures from one institution emphasizing the unique aspects seen in pediatrics. One hundred sixty-six children were included. Plain radiography and computed tomography scans were used to classify pelvic fractures. Multisystem injuries occurred in 60%, and 50% sustained additional skeletal injuries. The death rate was 3.6%. Head and/or visceral injuries were the causes of all deaths. Life-threatening hemorrhage did not occur. Urethral injury was not seen as often as in adults. Anterior ring fractures were the most common type, dominated by pedestrian versus motor vehicle trauma. Anatomical differences and mechanism of injury may play a role in these contrasting findings.

The orthopedists' perspective: bone tumors, scoliosis, and trauma

Although a detailed, comprehensive look at pediatric orthopedists' use of imaging is beyond the scope of this article, we offer an orthopedist's perspective of the role imaging plays in the care of children with tumors, scoliosis, and trauma. Given the growing, dynamic state of a child's skeleton, the long-term consequences of injury must always be considered.

Rethinking the role of phosducin: light-regulated binding of phosducin to 14-3-3 in rod inner segments

Phosducin (Pd), a small protein found abundantly in photoreceptors, is widely assumed to regulate light sensitivity in the rod outer segment through interaction with the heterotrimeric G protein transducin. But, based on histochemistry and Western blot analysis, Pd is found almost entirely in the inner segment in both light and dark, most abundantly near the rod synapse. We report a second small protein, 14-3-3, in the rod with a similar distribution. By immunoprecipitation, phospho-Pd is found to interact with 14-3-3 in material from dark-adapted retina, and this interaction is markedly diminished by light, which dephosphorylates Pd. Conversely, unphosphorylated Pd binds to inner segment G protein(s) in the light. From these results and reported functions of 14-3-3, we have constructed a hypothesis for the regulation of light sensitivity at the level of rod synapse. By dissociating the Pd/14-3-3 complex, light enables both proteins to function in this role.

A technique of occipitocervical arthrodesis in children using autologous rib grafts

STUDY DESIGN

Description of an operative technique with an illustrative case report.

OBJECTIVES

The technique is presented to provide an alternative to iliac crest graft procedures for achieving occipitocervical fusion in children. This technique is particularly useful in children with instability after extensive decompression or laminectomy and in children with a large protuberant occiput.

SUMMARY OF BACKGROUND DATA

The majority of techniques previously described for occipitocervical fusion in children rely on corticocancellous iliac crest autograft. Results generally have been promising; however, it can be difficult to harvest enough graft to span large defects after extensive decompression or to contour an iliac crest graft to a protuberant occiput. Structural rib autograft is superior in terms of availability and its unique and modifiable contour. Theoretical benefits of rib graft include superior strength and lower donor site morbidity.

METHODS

The surgical technique is described. A case of a 2-year-old boy with Down's syndrome and myelopathy secondary to cervical instability is reviewed.

RESULTS

The patient underwent occipitocervical arthrodesis using the technique described. The child made a full neurologic recovery, and at the 2-years follow-up evaluation, the graft had incorporated and the spine was stable.

CONCLUSION

A technique of occipitocervical arthrodesis in children is described using autologous rib graft. This procedure was designed to span large defects or to deal with a large protuberant occiput; however, it is also useful for less demanding cases and may offer several advantages compared with procedures relying on iliac crest graft.

The limping child: evaluation and diagnosis

A limp is a common reason for a child to present to the orthopaedist. Because of the long list of potential diagnoses, some of which demand urgent treatment, an organized approach to evaluation is required. With an understanding of normal and abnormal gait, a directed history and physical examination, and the development of a differential diagnosis based on the type of limp, the patient's age, and the anatomic site that is most likely affected, the orthopaedist can take a selective approach to diagnostic testing. Laboratory tests are indicated when infection, inflammatory arthritis, or a malignant condition is in the differential diagnosis. The C-reactive protein assay is the most sensitive early test for musculoskeletal infections; an abnormal value rapidly returns to normal with effective treatment. Imaging should begin with plain radiography. Ultrasonography is particularly valuable in assessing the irritable hip and guiding aspiration, if necessary.

Role of computed tomography in the classification and management of pediatric pelvic fractures

In adults, pelvic computed tomography (CT) scanning plays an important role in the treatment of pelvic fractures; however, the role of CT scanning in the management of pediatric pelvic fractures is unclear. The purpose of this study was to investigate the efficacy of CT scanning in the management of pelvic fractures in children. One hundred three consecutive patients were identified. All patients underwent anteroposterior plain radiographic evaluation; CT scans were performed in 62. Three orthopaedic surgeons independently reviewed the plain radiographs and determined fracture classification and management. Subsequently, each observer was shown corresponding CT scans and again determined classification and management. Interobserver agreement was calculated using Kappa statistics. After the addition of CT scans, the mean changes in classification were nine (15%) and in management two (3%). Plain radiographs alone reliably predicted the need and type of operative intervention. Kappa statistics demonstrated "excellent" agreement for classification and management without and with CT scans. We reliably determined fracture classification and management based on plain radiographs alone.

Titanium elastic nails for pediatric femur fractures: a multicenter study of early results with analysis of complications

Titanium elastic nailing is used instead of traction and casting in many European centers, but limited availability has prevented widespread use in North America. Before a planned general release in America, titanium elastic nails (TENs) were trialed at several major pediatric trauma centers. This multicenter study is a critical analysis of early results and complications of the initial experience. Overall, TENs allowed rapid mobilization with few complications. The results were excellent or satisfactory in 57 of the 58 cases. No child lost rotational alignment in the postoperative period. Irritation of the soft tissue near the knee by the nail tip occurred in four patients, leading to a deeper infection in two cases. As indications, implantation technique, and aftercare are refined, TENs may prove to be the ideal implant to stabilize many pediatric femur fractures, avoiding the prolonged immobilization and complications of traction and spica casting.

Campath-1H monoclonal antibody therapy

Monoclonal antibodies are receiving ever-increasing utilization in the treatment of hematologic malignancies. Campath-1 antibodies are directed against the surface antigen CD52 that is expressed on virtually all lymphocytes and monocytes. Murine forms, Campath-1G and Campath-1M, have been utilized extensively in allogeneic bone marrow transplants in order to purge the allograft of lymphocytes. The humanized form, Campath-1H, is currently the focus of many clinical trials in hematologic malignancies and autoimmune diseases. The genetically engineered Campath-1H has been utilized in the treatment of lymphomas and lymphoid leukemias with impressive results. T-cell prolymphocytic leukemia, chronic lymphocytic leukemia, and non-Hodgkin lymphomas appear to be particularly good targets for this agent. Campath-1H may be administered intravenously or subcutaneously. Infectious complications are the most significant side effect associated with its usage, with fevers, chills, nausea, and vomiting most common. Antibiotic prophylaxis has made the infectious morbidity associated with Campath-1H more manageable. The efficacy demonstrated in clinical trials and manageable toxicities make Campath-1H an appealing agent in the treatment of hematologic malignancies.

Closed ankle fractures in the diabetic patient

Systemic and local manifestations of diabetes mellitus may complicate the treatment of ankle fractures in the diabetic population. We studied 98 patients (73 non-diabetics and 25 diabetics) who were treated for closed ankle fractures by either surgical or non-surgical methods. We found that overall, the risk of infection in the diabetic population (32%) was 4 times higher than in the non-diabetic population (8%). The infection rate in the diabetic group treated surgically more than doubled that in the non-diabetic group. Four out of six diabetic patients treated with cast became infected compared to no infections in the five non-diabetics treated with a cast. Even though the diabetic foot and ankle are well studied, the medical literature is not conclusive regarding the management of ankle fractures in the diabetic patient. Diabetic patients treated conservatively had a tendency to become infected over those treated surgically. Peripherovascular disease, peripheral neuropathy and swelling and/or ecchymosis increased the risk of infection in the diabetic population. Diabetic patients with poor compliance had a tendency to become infected more than those who were compliant. We concluded that the diabetic patient who is poorly compliant with evidence of neuropathic disease, peripherovascular disease and severe swelling and ecchymosis presents the most difficult group to manage. Although these patients are poor surgical candidates, they are also the most difficult to manage and also most prone to infection and complications if treated conservatively. When faced with this difficult scenario a multidisciplinary team approach would probably yield the best possible results by early identification and intervention in these patients.

Fracture patterns in children and young adults who fall from significant heights

Trauma is a leading cause of morbidity and mortality for children and young adults. When all causes of trauma are considered, falls are the most common mechanism of injury. To address specifically age-related fracture patterns in children who fall, we identified 125 consecutive patients, 21 years old or younger, who fell from a height of 10 feet or greater. The medical records and radiographs for 110 of these patients were available for review. Patients were divided into three groups based on age: there were 25 infant/toddlers (0-2 years), 55 children (3-10 years), and 30 adolescent/young adults (11-21 years). We found statistically significant differences in fracture distribution between the groups. The adolescent/young adult group sustained a greater number of vertebral fractures (p<0.003) and total fractures per fall (p<0.015). The children, in contrast, had a greater number of long bone fractures (p<0.05). Knowledge of age-related fracture patterns could result in improved diagnosis and treatment of these injuries.

Objective evaluation of knee laxity in children

This study was designed to measure objectively knee laxity in children. Physical examination and the KT 1000 arthrometer were used to test the knee laxity of 150 healthy, uninjured children between 6 and 18 years of age. Data from the knee examinations and the KT 1000 measurements were compared and statistically analyzed to determine the change in knee laxity with age, laxity differences between boys and girls, and the correlation between the KT1000 measurements and subjective tests for laxity described by Carter and Wilkinson. There was no statistical difference in knee laxity between boys and girls of similar ages. We found that knee laxity, determined by measuring the millimeters of tibial translation using the KT 1000 arthrometer, was significantly greater in younger children.

Pyomyositis in children and adolescents: report of 12 cases and review of the literature

Pyomyositis initially was observed more commonly in the developing world but now is reported with increasing frequency in the United States. The presentation is nonspecific and the differential diagnoses are many. We found the clinical history, laboratory findings, and response to treatment similar to those observed in different areas of the world. Magnetic resonance imaging (MRI) with gadolinium injection, in addition to helping to make the diagnosis, may help differentiate between early and late stages that help guide treatment. Coexisting bone changes (58%) may represent either the sensitivity of MRI to reactive inflammatory changes or the presence of a coexisting osteomyelitis. All patients responded to antibiotics and drainage if abscesses were present. Although the optimal duration of antibiotic therapy remains unclear, a shorter course should be considered in patients with a good clinical response, even when MRI shows nonspecific bony abnormalities. Percutaneous drainage was successful in five cases and may represent an alternative to the traditional surgical approach.

Stem-cell transplantation in chronic lymphocytic leukemia: the time for designing randomized studies has arrived

Stem-cell transplantation in conjunction with myeloablative therapy has evolved as a standard treatment option for patients with several hematologic malignancies, including chemosensitive, relapsed non-Hodgkin's lymphoma and untreated multiple myeloma. The pharmacologic basis for this treatment includes a favorable tumor dose-response curve that abrogates intrinsic drug resistance associated with these diseases and facilitates cure or prolongation of survival even in the absence of a cure. The belief that chronic lymphocytic leukemia (CLL) is a palliative disease of the elderly has been perpetuated, limiting the application of more aggressive therapies. The introduction of fludarabine and its use in combination with other agents has increased the morphologic complete response rate observed in the initial treatment of CLL, providing the rationale to explore further disease-consolidative therapies. Concomitant with this, several phase II studies have demonstrated the feasibility of performing both allogeneic and autologous stem-cell transplantation in patients with CLL. In this regard, allogeneic transplantation has produced prolonged remissions in young patients with relapsed and refractory CLL, but at the cost of high treatment-related morbidity and mortality. Application of "minitransplantation" regimens may temper the frequency of these complications and warrants further study. Autologous stem-cell transplantation has also been explored with promising disease-free survival outcomes in less heavily pretreated patients. However, relapses continue to be the most frequent source of late mortality, as has been observed previously with multiple myeloma. With scientific justification established in similar diseases and demonstrated feasibility with low morbidity, we believe the time for a randomized comparison of standard chemotherapy versus autologous stem-cell transplantation in CLL has arrived. Despite promising results observed with allogeneic transplantation, further refinements that broaden the patient eligibility and lower treatment mortality will be required before similar investigations can occur with this modality.

Assessing, developing, and maintaining staff's competency in times of restructuring

Downsizing and reorganization in hospitals have resulted in nursing staff being realigned to different areas. During these times, nurse educators are continually challenged to provide effective educational programs to develop and upgrade staff competency. Nurse educators at a government health care facility in New York City experienced similar challenges as inpatient units were closed and staff had to develop or upgrade their skills. Two educational programs were designed to prepare staff to assume other duties, and competency assessments were developed and used to measure the effectiveness of the programs. Concepts relevant to competency assessment, development, and maintenance are discussed, and methods of assessments are described. Sample assessment tools and description of outcomes are included.

Seroprevalence of blood borne transmissible diseases in trauma orthopaedic surgical patients

OBJECTIVE

The purpose of this study is to determine the seroprevalence of blood borne transmissible diseases of the orthopaedic trauma surgical patients who deny or did not have knowledge of having disease or risk factors, but are positive for either human immunodeficiency virus, hepatitis B virus, and hepatitis C virus.

BACKGROUND

Orthopaedic surgeons practicing in areas with a high prevalence of HIV infection may expect that up to 7% of their patients who undergo emergency procedures and 1% to 3% of those who undergo elective surgery will be HIV-positive.

METHOD

All conscious adult patients consecutively admitted for surgical management by the orthopaedic service were evaluated. A detailed questionnaire was completed asking the patient of knowledge of having a transmissible disease and documenting certain risk factors. Blood samples were taken to test for HIV, HBV and HCV and all positive patients were sent to a follow up clinic.

RESULTS

Out of 100 patients the following results were found: 7% were positive for HIV, 12% positive for HBV, 12% positive for HCV, 19% were positive to at least one test, and 9% were positive in more than one test. Of the one hundred patients, 6% had a positive test in spite of denying having a disease or any risk factors. None of the patients with HBV and/or HCV knew they were positive and three (43%) of the seven with HIV were also unaware of their condition.

CONCLUSIONS

This study suggests that a worrisome number of patients are seropositive for a blood borne transmissible disease, even though they had no knowledge of such disease and claimed they had no risk factors. In order to protect orthopaedic surgeons from the unreliability of some patients' histories, all trauma orthopaedic surgical patients should be managed with universal precautions.

Segmental spinal dysgenesis: early neurologic deterioration and treatment

Segmental spinal dysgenesis is a rare congenital condition of the lumbar or thoracolumbar spine that can be associated with significant progressive or permanent neurologic defects, including paraplegia. In the past, both bracing and surgery have been recommended. Of the seven children we have seen with this problem, three have lost motor function between presentation and the time of surgery. Our experience suggests that to prevent catastrophic neurologic deterioration, surgery is indicated once the diagnosis is made.