Design and construction of a 9 MeV γ-ray source based on capture of moderated plutonium-beryllium neutrons in nickel.

We have designed and constructed a high-energy γ-ray source for detector characterisation and calibration. The source is a composite type based on a plutonium-beryllium neutron emitter embedded in a paraffin moderator, which is homogeneously mixed with nickel powder. The 9 MeV γ-ray source produces approximately 450 photons per second in 4π when 2.2×105 neutrons per second are emitted, corresponding to a surface flux of 9 MeV γ-rays of approximately 2.5×10-6 cm-2 per emitted neutron. Here we discuss the properties and design of this source, including the characterisation of homogeneity and high-energy γ-ray emission spectra.

Achieving excellent microformability in aluminum by engineering a unique ultrafine-grained microstructure.

During microforming of conventional materials, specimen and microstructural length-scales are close to each other. This leads to an abnormal deformation behavior of the material and reduces microformability. Engineering ultrafine-grained (UFG) microstructure in the material is a possible solution. However, micro-scale deformation behavior of UFG material is not fully understood. Present work attempts to comprehensively investigate the micro-scale deformation of four distinctly engineered microstructures: UFG with residual dislocations and elongated grains, UFG free of residual dislocation with equiaxed grains, bimodal-grained and coarse-grained. The deformation behavior is captured via micro-scale uniaxial tensile test and micro-deep drawing operation. Micro-cups generated from UFG material with equiaxed grains show excellent surface quality, form-accuracy and minimal process scatter. Postmortem microscopy of the formed micro-cups attributes this improved microformability to the activation of grain boundary-mediated plasticity in the material which results in synergetic grain migration and rotation. Presence of residual dislocations and elongated grains hinders the grain migration and rotation leading to strain localization and thinning. In case of bimodal and coarse-grained material, cross-slip based deformation mode progressively dominates over grain migration and rotation, which results in a reduction in microformability due to the influence of size-effect.

Salvage of limbs with vascular trauma.

In an eight-year period we treated 51 cases of vascular injury associated with fractures and/or dislocations or soft-tissue injuries of the limbs. We relied on a clinical diagnosis and immediate exploration of blood vessels rather than the time-consuming procedure of arteriography. All patients were operated on by the orthopaedic residents on duty and not by vascular surgeons. Only 17 (33%) were repaired within six hours of injury. Limb viability with good function was obtained in 38. Complications included six deaths, four amputations, two renal failures and delayed occlusion in one case.

External fixation of intertrochanteric fractures of the femur.

External fixation was used in the treatment of 154 intertrochanteric fractures of the femur over a period of eight years. Good fixation and early ambulation was achieved in all cases. Blood loss was slight. There were 12 deaths due to medical causes unrelated to the surgical procedure. Deep pin-track infection occurred in six cases and late displacement of the fracture fragments in nine. The average time for union was 16 weeks. The technique is simple, quick and inexpensive, and causes minimal surgical trauma. All these features are particularly relevant where resources are limited.

Deep vein thrombosis after total hip arthroplasty in Indian patients with and without enoxaparin.

PURPOSE: To study the incidence of deep vein thrombosis in Indian patients undergoing total hip arthroplasty with or without prophylaxis, and the effect of enoxaparin on deep vein thrombosis. METHODS: The study covered a total of 50 hips in 40 patients who underwent total hip arthroplasty. Patients were assessed for deep vein thrombosis using Doppler ultrasonography. The hips were numbered and divided into 2 groups: the odd-numbered hips did not receive any thrombo-prophylaxis, whereas the even-numbered hips received 40 mg of enoxaparin subcutaneously, once a day for 2 weeks, until the time of discharge. RESULTS: Deep vein thrombosis was not found in both groups. We found wound haematomas in 9 patients (all of whom were on enoxaparin) (p<0.05), superficial infection in 2 patients (one on enoxaparin, one not), and local bruising in 4 patients (all of whom were on enoxaparin). Major haemorrhage did not occur in any of the cases. CONCLUSION: The incidence of deep vein thrombosis in Indian patients is very low compared to that in European and American patients. Enoxaparin failed to provide any advantage to the patients. It is therefore not advisable to give prophylaxis/low-molecular-weight heparin for deep vein thrombosis to patients undergoing total hip arthroplasty without any risk factors.

Giant cell tumour of soft tissue--a case report.

Giant cell tumor is seen in late adolescence or in the third or fourth decade of life. It arises from epiphysis of long bones, the commonest site being the distal end of the demur and the proximal end of tibia. This paper presents a case report of giant cell tumor of soft tissue.

Giant cell tumour of soft tissue--a case report.

Giant cell tumor is seen in late adolescence or in the third or fourth decade of life. It arises from epiphysis of long bones, the commonest site being the distal end of the femur and the proximal end of tibia. This paper presents a case report of giant cell tumor of soft tissue.

Functional restoration after early tendon transfer in high radial nerve paralysis.

We assessed the effect of an early transfer of pronator teres to extensor carpi radialis brevis on hand function in patients with high radial nerve paralysis. Power grip and precision grip were measured preoperatively and postoperatively using a dynamometer. Fifteen patients were operated on, of which ten could be assessed at the end of 6 months. At 6 months after surgery, there was a median increase of 48% in power grip, 162% in tip pinch, 90% in key pinch and 98% in palmar pinch. Decreased palmar flexion was seen in four patients. Fraying of the periosteal extension and rupture of sutures at the junction site were each seen in one patient, leading to unsatisfactory results. Early tendon transfer quickly restored efficient grip while awaiting reinnervation of wrist extensors, avoiding the need for prolonged external splintage.

Volkmann sign of non-ischaemic origin.

This paper presents six cases who had a contracture of the long flexor tendons of the fingers and exhibited Volkmann's sign due to a chronic abscess or cysticercosis in the belly of the flexor digitorum profundus. All of them were treated conservatively, with full functional recovery in all the cases and with no recurrence.

Is life only precious at 20 weeks?

PIP: The experience of India demonstrates the insufficiency of abortion legalization without concomitant measures to make the procedure accessible, safe, and affordable. Abortion is permitted up to 20 weeks, and all 38 clinics of the Family Planning Association of India are equipped to perform the procedure at a cost of Rs60. However, services are inadequate to meet the demand in a context where abortion is the 4th most widely used method of fertility control. As a result, half a million Indian women die each year from complications of clandestine abortions performed by quacks. Parivar Seva Sanstha (PSS), the Indian affiliate of Marie Stopes International, is fighting to make abortion more accessible and to use the abortion visit to introduce effective contraception. Total reproductive care is provided by PSS at 31 clinics throughout India, and 3 mobile units travel to 65 villages. 80% of PSS clients accept family planning services. Subsidized treatment is available to abortion seekers unable to pay the nominal fee. The success of this program demonstrates the crucial role of abortion in family planning services.^ieng

Biological fixation of subtrochanteric fractures by external fixation.

Fifty-one subtrochanteric fractures have been stabilized by external fixation over the last 9 years. Union occurred in all types of fractures, usually within 6 months. Soft tissue interposition led to non-union in three patients. Refracture in one patient and significant limb-length discrepancy in two patients was seen. The technique is versatile, easily reproducible and 'biological'. Protected weight-bearing is not necessary after removal.

Spinal epidural abscess - a report of six cases.

Six cases of spinal epidural abscess are presented. All patients were young with no predisposing conditions. All were treated with laminectomy and intravenous antibiotics. The patients with no neurological deficit recovered completely, while patients with pre-existing neurological deficit had a poorer outcome. Emphasis is given to early detection and surgical management to prevent irreversible damage to the spinal cord.

Encounters with pseudoaneurysms in orthopaedic practice.

Thirteen pseudoaneurysms are presented of which five were caused as a complication of pin/wire placement of external fixators (one conventional and four Ilizarov frames). The most common symptom was the presence of profuse persistent bleeding from either the wound or the pin/wire site. In nine patients the pseudoaneurysm was directly caused by a fracture or subsequent fracture stabilisation. Pre-operative evaluation included radiography, arteriography, Doppler and computed tomography (CT) angiography. Depending on the site and size of the pseudoaneurysm management consisted of either ligation, resection and end-to-end anastamosis/vein grafting, lateral suture, endoaneurysmorrhaphy or selective embolisation.A high index of suspicion needs to be maintained following penetrating injury in the vicinity of a major vessel, particularly in the presence of persisting symptoms. External fixators are widely used to treat complex orthopaedic problems. The procedure is technically demanding, requiring a sound knowledge of cross-sectional limb anatomy. Injudicious use may result in potentially life/limb threatening complication of pseudoaneurysm.