Sensitivity of fresh isolates of soft tissue sarcoma, osteosarcoma and giant cell tumour cells to Apo2L/TRAIL and doxorubicin.

Chemotherapy is an established treatment modality for bone sarcomas such as osteosarcoma (OS). However, the use of chemotherapy in high-grade soft tissue sarcomas remains controversial, with the most active chemotherapeutic agent, doxorubicin (DOX), reported to have a response rate of, at best only 34% and most studies reporting lower response rates. Apo2L/TRAIL is a member of the tumour necrosis factor (TNF) family of cytokines and induces death of tumour cells, but not normal cells. Its potent apoptotic activity is mediated through cell surface death domain-containing receptors, DR4/TRAIL-R1 and DR5/TRAIL-R2. We investigated the efficacy of Apo2L/TRAIL as a single agent, and in combination with clinically relevant chemotherapeutic drugs, in fresh isolates of primary malignant cells obtained from biopsy material. The data presented here demonstrate that, in a range of primary bone related tumours, as well as soft tissue sarcomas, chemotherapeutic agents were only moderately effective, in terms of induction of cell death. Apo2L/TRAIL alone had little or no effect on any bone-related tumour or sarcoma in culture. In contrast, the combination of Apo2L/TRAIL and chemotherapeutic drugs produced a significant increase in tumour cell death, with DOX and Apo2L/TRAIL proving to be the most effective combination. These data suggest the potential for Apo2L/TRAIL to increase the effectiveness of chemotherapeutic drugs in bone and soft tissue sarcomas, while perhaps concurrently allowing a reduction in the exposure to drugs such as DOX, and a consequent reduction in toxicity. The synergistic action between these two different classes of agents has yet to be tested in vivo but may prove clinically relevant in the treatment of this refractive class of malignancies.

Treatment of pathological fractures of the humerus with a locked intramedullary nail.

OBJECTIVE: The humerus is a common site for metastasis. Intramedullary nail fixation has been reported to be the best form of fixation for this disease but complications occur. This study aimed to assess the use of a new humeral nail to treat pathological fractures and impending pathological fractures of the humerus. METHODS: 29 patients received 31 Austofix locked intramedullary humeral nails: 25 for pathological fractures and 6 for impending fractures; 24 nails were inserted anterograde and 7 retrograde. Cement augmentation was applied in 4 patients, and adjuvant therapy was used in 28 patients. Complications occurred in 12 patients. RESULTS: Fixation failed in 6 patients: 2 due to intraoperative fractures during retrograde nailing, one due to a fracture through screw holes postoperatively, and 3 due to local progression of disease. Difficulty in distal locking of the nail was encountered in 4 patients. Locked intramedullary nailing resulted in a stable humerus in 80% of patients. CONCLUSION: Retrograde insertion of the nail is associated with an increased risk of intra-operative fracture, and disease progression can occur, despite the administration of adjuvant therapy.

Expression of alternatively-spliced MDM2 transcripts in giant cell tumours of bone.

Giant cell tumours of bone (GCT) are characterized histologically by multinucleated bone resorbing giant cells in a background of ovoid spindle-shaped mesenchymal cells. Current evidence suggests that the latter comprise the tumour element of these lesions, although there are basic questions as to the factors that contribute to the tumourigenesis and progression of GCT. The deregulation of the p53/MDM2 pathway is an important pathogenetic event in many tumour types, prompting us to assess the expression of MDM2 by the stromal cells and giant cells of GCT. Northern blot analysis demonstrated that most of the GCT samples examined expressed increased levels of MDM2 when compared to normal human bone cells. However, Southern analysis failed to show any evidence of MDM2 gene amplification in the same samples, suggesting that increased levels of MDM2 mRNA were not a direct result of gene amplification, but rather due to altered transcriptional regulation of MDM2 gene. By RT-PCR analysis we found that 7/8 giant cell tumours expressed strongly a short alternatively spliced variant of MDM2, whereas other tumours of bone and normal human bone cells expressed predominantly full length MDM2. Sequence analysis confirmed this variant to be MDM2-b, a variant previously reported to confer a transformed phenotype. Cell fractionation of the GCTs has shown that the MDM2-b splice variant was expressed exclusively in the stromal population, whereas the full length MDM2 was expressed in the multinucleated giant cells of these lesions. Overexpression of a green fluorescent protein-tagged MDM2-b in human embryonic kidney cells (HEK-293), demonstrated predominantly nuclear localisation. Immunoprecipitation studies showed that MDM2-b is unable to physically associate with the p53 tumour suppressor protein. These results are consistent with the hypothesis that the stromal cells comprise the tumour element in giant cell tumours of bone and we speculate that expression of the MDM2-b splice variant contributes to their transformed phenotype in a p53 independent manner.

Enhanced apoptosis of soft tissue sarcoma cells with chemotherapy: A potential new approach using TRAIL.

Soft tissue sarcomas are less responsive to conventional chemotherapy when compared to bone sarcomas. We investigated the possibility of enhancing the efficacy of chemotherapy by utilising the recently identified cytokine, tumour necrosis factor-related apoptosis-inducing ligand (TRAIL/Apo2L) in combination with standard chemotherapeutic agents. Fresh human soft tissue sarcomas (rhabdomyosarcoma, fibrosarcoma, malignant fibrous histiocytoma) were obtained at biopsy and dispersed tumour cells were incubated in cell culture with standard cytotoxic agents, either as single agents or in combination with TRAIL. The chemotherapeutic agents were, at best, moderately effective, in terms of induction of cellular apoptosis, although the fibrosarcoma was completely unresponsive to all single agents. TRAIL alone had no effect on any sarcoma cell culture. In contrast, the addition of TRAIL and drug together produced a significant increase in sarcoma cell apoptosis, with TRAIL and doxorubicin the most effective combination.

Occult hypoxia after femoral neck fracture and elective hip surgery.

The incidence of hypoxia after femoral neck and total hip arthroplasty was investigated. In addition, the incidence of preoperative and postoperative delirium was assessed. Oxygen saturation and mental status were tested before and after surgery in patients undergoing surgery for a femoral neck fracture or total hip arthroplasty. Hypoxia was present before surgery in five of 50 patients who underwent total hip replacement and 17 of 50 patients with femoral neck fractures. On Day 1 after surgery, 20 patients who underwent total hip replacement and 36 with femoral neck fractures had hypoxia; on Day 3 after surgery, 12 patients who underwent total hip replacement and 17 with femoral neck fractures had hypoxia. Respiratory recovery was quicker in patients after total hip replacement with 39 who recovered by Day 3 after surgery, compared with 31 patients with femoral neck fractures. Preoperatively, patients with femoral neck fracture had significantly lower mental test scores than did patients who had undergone total hip replacement, and this continued on Day 1 after surgery. However, by Day 3 after surgery, there was no significant difference between the groups. Although the scores for the patients with femoral neck fractures were lower, delirium developed in only three patients with total hip replacements and six patients with femoral neck fracture. Hypoxia after hip surgery, particularly after femoral neck fracture, is common. The incidence of delirium was much lower than reported previously, and it is suggested that supplemental oxygen, when indicated and monitored by pulse oximetry, was the cause for the reduction in delirium.

The outcome of Austin-Moore hemiarthroplasty for fracture of the femoral neck.

One hundred and fifty-four consecutive patients who sustained a fracture of the femoral neck and were treated with an Austin-Moore hemiarthroplasty were followed up longitudinally for 10 years, or until revision of the prosthesis, or death of the patient. Clinical assessments were performed at 1, 3, 5, and 10 years after surgery. At 3 years, 46% of the patients were community ambulators; 10%, household ambulators; 6%, nonfunctional ambulators; 29%, nonambulators; and 9% unknown. At 10 years, 31% were community ambulators; 35%, household ambulators; 4%, nonfunctional ambulators; and 30%, nonambulators. Men had statistically significantly better ambulation than women at the 3-year review (P = 0.004), but there was no difference at later assessments. The Harris hip score was 69 (range, 41 to 97) at 5 years and 69 (range, 25 to 90) at 10 years. The overall failure rate was 6.5% at 5 years and 7.7% at 10 years. The revision rate was 4.5% at 5 years and 5.2% at 10 years. Patients younger than 70 years at the time of fracture had a statistically significantly higher revision rate than did older patients.

The results of coraco-clavicular slings for acromio-clavicular dislocation.

BACKGROUND: Treatment of type 3 acromio-clavicular (A-C) dislocations is controversial. There have been over 60 different surgical procedures as well as a variety of conservative measures used to treat this injury. METHODS: The outcome of a coraco-clavicular (C-C) sling for grade 3-4 A-C dislocation was studied. A dissolvable sling of braided 1 polydioxanone (PDS, Ethicon) was used with or without excision of the distal end of the clavicle in six patients. The clinical and radiological outcome of the braid and acromio-clavicular joint were studied by clinical examination, plain and stress radiographs and magnetic resonance imaging (MRI). RESULTS: All patients reported good-excellent results from 6 months after surgery. Radiological examination demonstrated some superior clavicular migration in all patients within 1 month of the procedure, although never more than that seen with a grade 2 dislocation. This migration was clinically evident only in patients with a thin build. At 1 month, the MRI demonstrated partial replacement of the braid by granulation tissue. From 6 months on, the braid was absent and fibrous tissue was noted between the coracoid and the clavicle and the acromion and clavicle. CONCLUSIONS: The coraco-clavicular sling did not maintain operative reduction of the dislocated clavicle. This did not diminish the functional result but was a cosmetic complication in patients with a thin build.

Growth disturbances associated with untreated benign bone cysts.

BACKGROUND: The occurrence of benign bone cysts adjacent to an active physis may be associated with a physeal arrest. That arrest may result from physeal penetration of the cysts itself, secondary pathologic fracture or the result of surgical curettage. METHODS: The pre-treatment X-rays of patients attending the Bone Tumor Clinic at the Children's Hospital and Medical Center were reviewed. Those patients presenting with a bone cyst were identified and the affected side was compared to the normal side in order to determine growth discrepancies. RESULTS: Three cases of benign bone cysts are presented that were located adjacent to a growing physis nad produced growth disturbance in the absence of surgical intervention. CONCLUSIONS: The risk of growth disturbance in itself should not be a contraindication to surgical intervention.

IgG-mediated phagocytosis in regenerated splenic tissue.

The risk of severe infections after splenectomy is well established. Operations such as auto-transplantation, splenic artery ligation or partial resection have been advocated for the retention or regeneration of splenic tissue following splenic trauma. The potential of such tissue to protect from infection is unclear. The ability of splenic tissue to phagocytose IgG opsonized syngeneic erythrocytes was measured in rats 6 months following splenectomy and splenic autotransplantation, splenic artery ligation, total or partial splenectomy, and compared with eusplenic controls. In eusplenic and partially splenectomized rats 71% of the label was cleared at 3 h, compared with approximately 50% in rats following total splenectomy, splenectomy and splenic autotransplantation or splenic artery ligation. The autotransplanted and the ligated splenic tissue cleared less than 10% compared with control spleen, but there was no difference between them when clearance was expressed as uptake per gram of tissue. Splenic autotransplants and ligated spleens were small and histologically abnormal, with an increase in the red pulp, significantly less white pulp and marginal zone, and the frequent absence of a central arteriole in the white pulp. The clearance of label was proportional to the amount of red pulp in the tissue, although the red pulp from the regenerated tissues was not as efficient at phagocytosis as control red pulp. The tissue which regenerated following autotransplantation or splenic artery ligation did not result in greater clearance of erythrocytes from the circulation than that which occurred in splenectomized rats.

A method of pre-operative assessment for posterior cruciate ligament reconstruction.

The use of the bone-patellar tendon-bone graft has been well established in anterior cruciate ligament (ACL) reconstruction. The value of this graft in posterior cruciate ligament (PCL) reconstruction has not been documented. A template was used to identify the origin and insertion of the PCL on standard lateral radiographs of the knee. Those patients who were found at arthroscopy to have an intact articular surface were measured using the template. Thirty-nine patients (40 knees) were included for study, the difference between the PCL and patellar tendon length was expressed as a percentage. The mean was 125% (range 98-165%). To assess the reproducibility of the technique, in 17 patients a repeat radiograph was taken and the two measurements compared. These were found to have a significant correlation (Rs coefficient 0.79, P < 0.001). The use of autologous bone-patellar tendon-bone graft obviates the need for allograft with its incumbent problems. This method of measurement indicates that the patellar tendon graft would be long enough to be suitable for PCL reconstruction in the majority of cases.

Allograft bone in the treatment of desmoplastic fibroma. A case report.

A 17-year-old girl had a desmoplastic fibroma of the distal femur. This rare tumor is managed by surgery alone and requires a marginal to wide resection because of its high risk of local recurrence. Had the tumor invaded into the epiphysis and marginal resection, it would have resulted in loss of articular femoral condyle. It was treated by en bloc proximal resection with distal intralesional curettage and anatomic specific allograft femoral replacement. There was no recurrence of the tumor three years after surgery, and function was excellent.

Longitudinal stress fracture of the tibia: two cases.

Stress fracture of the tibia occurs in individuals who subject their extremities to repeated trauma. They can arise in otherwise healthy bone that is subjected to excessive loads (as in the marathon runner) or in abnormal bone that is subjected to minor loads (as in osteoporosis). These fractures may be anywhere along the tibial shaft and tend to be either transverse or oblique in orientation. We report two cases of stress fracture that ran longitudinally in the distal one third of the tibia. Both patients were healthy and did not describe excessive physical activity prior to fracture. Both describe a repetitive twisting action prior to fracture. Computed tomography was diagnostic in both cases following abnormal bone scans and normal plain radiographs. This unusual pattern of fracture has been reported on only four occasions in five patients in the literature.

The vascular supply of splenic autotransplants.

The close opposition of blood to phagocytic cells lining the pulp cords and marginal sinus has been proposed as a contributing factor in the clearance mechanism of the spleen. The vasculature of splenic autotransplants was investigated in rats using microcorrosion casts. Six-month-old splenic autotransplants and unoperated control spleens were selectively perfused and a methyl methacrylate cast was made. Scanning electron microscopy of these corroded casts was performed. In autotransplants, the marginal zone capillary network was abnormal with the fine network of capillaries replaced by dilated blood vessels. The red pulp cords were also found to be abnormal with increased diameter and loss of the fine saccular dilations found in normal spleens. The abnormally dilated capillaries and cords in the autotransplants may decrease antigen contact with these cells and hence explain previous reports of reduced phagocytic function.

Antibody responses following splenectomy: implications for the timing of prophylactic vaccination.

Antibody responses are reduced both in the short- and long-term after splenectomy. It is not known if this reduction is more profound in the immediate postoperative period compared to later, and consequently, whether there would be an advantage in delaying prophylactic vaccination to ensure a greater antibody response. To investigate this, the effect of splenectomy on the primary and secondary antibody response to sheep red blood cells (SRBC) injected into the peritoneum (IP) of adult male Porton rats was measured after either splenectomy (Spx), sham splenectomy (Sham), anaesthesia only (Ans) or no procedure at all (Con). There was no difference in the titres of antibody between the Con and the Ans rats. There was no difference in the titres of antibody between the Sham and Spx rats, but both had significantly lower titres than the Con rats. In a separate experiment, rats were immunized 1 month or 1 year after splenectomy or sham-splenectomy. One month after the operation the antibody response of the Sham rats had increased and did not differ from that of Con rats, but in rats which had been splenectomized there was a long-term suppression of the antibody response, which did not improve for at least one year. The results suggest that, in patients requiring splenectomy for trauma and not able to be vaccinated before operation, there may be no advantage in delaying prophylactic vaccination postoperatively.

Comparative study of skin closure in hip surgery.

A prospective, randomized controlled study was performed to compare skin staplers for closure of skin following hip surgery. Patients were randomized to have their skin closed with either continuous subcuticular non-absorbable polypropylene 'prolene' suture (33 patients) or metal skin staples (Autosuture 'Premium' or Davis and Geck 'Oppose'; 33 patients). All patients received prophylactic cephalosporin (Cephalothin) in pre- and postoperative antibiotic therapy. The wounds were examined daily and the presence of discharge, wound dehiscence and infection were noted. Any discharge at 7 days was swabbed for microbiological examination. The final cosmetic appearance was assessed at 8-12 weeks postoperatively. Scar length and width were measured and the presence of cross-hatching noted. Wound dehiscence occurred in 1 patient (closed with staples). Wound infection developed in 2 patients at a rate of 3% (1 patient from each group). At final review (8-12 weeks postop), the scar produced by subcuticular prolene was narrower than that produced by the skin stapler (P less than 0.05). There was no significant difference in scar width between a wound which had staples removed at 10 days post operation and one where the staples were removed at 14 days. Staple insertion sites were more obvious in scars that had had the staples removed at the later time (P less than 0.05).

Morbidity and mortality following fractures of the femoral neck and trochanteric region: analysis of risk factors.

A retrospective review of casenotes with patient review at 3 years was carried out of 405 patients who had surgery for fracture of the femoral neck (including the trochanteric region). The operative management consisted of either internal fixation (61%), hemiarthroplasty (38%), or total arthroplasty (1%). Medical complications developed in 30% of patients; surgical complications developed in 14%. The mortality rate was greater for the first 9 months after operation, but thereafter approached the rate found in the general population (matched for age and sex). Followup 3 years postoperatively recorded 50% of patients still alive. Factors associated with death within the first postoperative year included increasing age, male sex, and the presence of dementia or congestive cardiac failure. Of the survivors, 55% described unlimited range of mobility but 32% reported only poor mobility (progressive dementia being the most common cause). Factors associated with poor mobility were increasing age, female sex, placement in an institution, and the presence of dementia or cerebrovascular insufficiency. Transfer to the specialist rehabilitation ward postoperatively was associated with significantly improved survival and mobility.