The rare aggressive osteoblastoma in a two year old child in an unusual localization.

A rare bone tumor of 3rd metacarpal bone in a male child aged 2 years is being described. The patent presented with a gradually increasing, painful swelling over the dorsum of right hand which radiologically revealed an expansile, radioluscent mass, in 3rd metacarpal shaft with cortical destruction. The clinic-radiological differential diagnosis was aggressive cartilage tumor or an osteomyelitis. Histological examination of surgical biopsy material revealed randomly arranged woven bone lined by epithelioid osteoblast and after correlating the clinic-radiological features the diagnosis was an aggressive osteoblastoma. Appropriate diagnosis of such a rare tumor in an unusual location and age group facilitate adequate management by surgery alone without radiotherapy or chemotherapy.

Structure-function alteration of hemoglobin in arsenicosis patients: a probable pathway to exert toxicity.

Chronic arsenicosis, a major public health concern in India and Bangladesh, is mainly caused by ingestion of arsenic (As) contaminated ground water. Although this problem has been studied extensively, the mechanism of toxicity remains unknown. This paper investigates the process of trivalent arsenicals binding to hemoglobin (Hb) in chronic arsenicosis patients and consequent modification in the structure-function activity of Hb. In this work peroxidase activity, thermal denaturation profile, oxygen releasing capacity and hydrodynamic diameter have been evaluated for the Hb collected from subjects suffering with chronic arsenicosis. Increased peroxidative activity suggests altered oxidative status of Hb in the diseased state. The thermal denaturation profile indicates the Hb molecule to be more susceptible to unfolding in the pathologic state. The enhanced oxygen releasing capacity and significant reduction in hydrodynamic diameter of Hb is also observed in the diseased condition, suggesting conformational alterations in the Hb molecule. Finally, trivalent arsenic is found to bind with freshly isolated Hb from arsenicosis patients, binding affinity constant being 0.256 µM⁻¹. The binding is positively cooperative with a Hill coefficient of +2.961 and isosbestic points at specific wavelengths. Thus, our work explores the structure-function property of Hb in chronic arsenicosis subjects and reveals that the molecule is modified in such a way that comparatively weak binding with oxygen and strong binding with arsenic occur simultaneously. This association may play a crucial role in exerting the pathway for arsenic toxicity.

Evaluation of pedicular screw fixation in dorsolumbar spinal injury.

Twenty-five patients with dorsolumbar spinal injury was treated by pedicular screw fixation along with direct or indirect decompression within 1 1/2 years period. Eighteen patients with incomplete neurodeficit had some amount of neurological recovery in terms of ASIA impairment scale but no neurological recovery was seen in 6 patients with complete neurological injury. Mean correction of kyphotic angle was 11.76 degrees. Mean postoperative increase in anterior vertebral body height was 43%. Complications like bed sore, superficial wound infections and peroperative dural tear were seen but all of which were treated successfully. Neurological deterioration after operation, screw pull out and implant failure were seen in none. This study indicates that short segment pedicular screw fixation is a safe and effective method for treatment of unstable spinal injury.

Percutaneous fixation of displaced intra-articular calcaneal fracture.

Operative treatment modalities for calcaneal fracture are still controversial. The outcome of intra-articular calcaneal fracture is mainly influenced by the soft tissue and the subtalar joint. Percutaneous method of internal fixation has been attempted to avoid the problems. Patients with displaced intra-articular calcaneal fracture types IIA, IIB and IIC were treated by initial distraction of subtalar joint, restoration the of subtalar joint, reduction of lateral expansion and finally fixation with screws percutaneously. Twenty-two patients with 26 calcaneal fractures were included. After a mean follow-up of 2 1/2 years and with American Orthopaedic Foot and Ankle Society hind foot score 82 points out of 100. Percutaneous fixation of calcaneum fracture is good alternative method in types IIA, IIB and IIC and selective type III fractures.

An evaluation of flexible intramedullary nail fixation in femoral shaft fractures in paediatric age group.

Sixty-two femoral shaft fractures in 60 patients treated by elastic intramedullary nailing with mean age of the patients being 9.2 years (range 5 years to 12 years) and average follow-up of 15 months (range 7 months to 60 months) are evaluated. Twenty-eight fractures were fixed with titanium elastic nail while 34 fractures were fixed with Enders nail. There were 40 midshaft fractures, 18 proximal femoral and 4 were fractures of distal third. Fracture patterns were transverse in 35, short oblique in 14 cases and 13 were spiral fractures. Mean age of union in this series was 17 weeks (range 12 weeks to 28 weeks). Ten cases had complications, 5 had nail tip irritation, 3 varus or valgus malalignment and 2 had delayed union. In this series, we did not have any non-union, refracture, limb length discrepancy or any major infection. The result demonstrates 100% union rate irrespective of the age, weight and height of the patient. Regardless of the site of fracture and their pattern, it united every time with elastic nail fixation. We did not find and mismatch in the results of fractures stabilised with titanium elastic nail with that of elastic stainless steel nail.

Operative management of closed intra-articular fractures of distal end of humerus in adults.

This is a study of 60 patients with mean age of 30 years having intra-articular fracture of distal humerus of type C (AO classification). We treated these fractures by open reduction and internal fixation through transolecranon approach. Mean duration of operative time with that of injury was 10 days. In all the cases 1st the intracondylar fracture was fixed followed by reconstruction and stabilisation of medial and lateral pillar by 1/3 tubular plate and 3.5 mm dynamic compressent plate (DCP) or recon plate respectively. Minimum follow-up was of 1 year duration with average follow-up of 3 years. We could achieve 100% union with mean range of movement at the and of 1 year was 20 degree to 110 degree. Two fractures had delayed union, 5 patients had skin complications for which extended dressing was required. None of these patients required SSG or secondary suture.

DNA hypermethylation of promoter of gene p53 and p16 in arsenic-exposed people with and without malignancy.

Chronic arsenic exposure is known to produce arsenicosis and cancer. To ascertain whether perturbation of methylation plays a role in such carcinogenesis, the degree of methylation of p53 and p16 gene in DNA obtained from blood samples of people chronically exposed to arsenic and skin cancer subjects was studied. Methylation-specific restriction endonuclease digestion followed by polymerase chain reaction (PCR) of gene p53 and bisulfite treatment followed by methylation-sensitive PCR of gene p16 have been carried out to analyze the methylation status of the samples studied. Significant DNA hypermethylation of promoter region of p53 gene was observed in DNA of arsenic-exposed people compared to control subjects. This hypermethylation showed a dose-response relationship. Further, hypermethylation of p53 gene was also observed in arsenic-induced skin cancer patients compared to subjects having skin cancer unrelated to arsenic, though not at significant level. However, a small subgroup of cases showed hypomethylation with high arsenic exposure. Significant hypermethylation of gene p16 was also observed in cases of arsenicosis exposed to high level of arsenic. In man, arsenic has the ability to alter DNA methylation patterns in gene p53 and p16, which are important in carcinogenesis.