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Over the past decades motor vehicles became the primary mode of transportation in developing countries. At the same time an improvement in automotive engineering and manufacturing as well as the phenomena of urbanisation have resulted in more vehicles spending more time on the road at higher speeds. Invariably this leads to driving scenarios where safety critical manoeuvres have to be performed that rely on the mechanical condition of the vehicles. In developing countries, where economic realities force the population to make use of older and less reliable vehicles, the risk of accidents caused by some sort of mechanical failure increases. The casualty rate (events causing death and/or serious injuries) for road traffic accidents in South Africa is amongst the highest in the world. This trend has persisted with little variation over the years, despite the efforts of local road safety organisations and research institutes to decrease them. The main goal of this study was to establish the contribution of mechanical failures to motor vehicle accidents, and furthermore, to compare it with international trends. Data obtained from accident response units (ARU) indicate that tyres and brakes were the main contributors to mechanical failures resulting in accidents in the Pretoria region (Gauteng Province). However, the reported percentage of approximately 3% is comparable to similar statistics from developed countries. Detailed information on the condition of road-going vehicles was then collected in this area. The roadside survey (potential mechanical defect tests (PMDT)) indicated that 40% of the vehicles surveyed on the suburban road and 29% of the vehicles surveyed on the highway had mechanical defects that contravened current road and traffic regulations in South Africa and may, therefore, be at risk of causing an accident due to a mechanical failure. In the Minibus (taxi) survey, large irregularities in tyre inflation pressure were identified as a cause of concern. The main conclusion from this work is that tyres and brakes are the two most dominant components that contribute to the mechanical defects causing accidents, with overloading an additional factor to consider. It is important to acknowledge that these three factors can easily be monitored during simple roadside inspections.

In this paper, a basic test specification is proposed to assess the structural integrity of a canopy that covers the load-area of a light commercial vehicle (LCV) used to carry passengers in the rear. The proposed test specification is a first step towards improving the safety of these passengers during rollover accidents. Different test methods were evaluated for applicability, ease of use and financial implications. The mass and geometric characteristics of three different one-ton LCVs were experimentally obtained and used to determine the minimum lateral velocity that will result in a rollover should a tripping mechanism be encountered. These velocities, in conjunction with other published data, were used to determine the energy required for a pendulum qualification test. It was decided that 7.7 kJ of energy delivered by a pendulum travelling between 4 and 7 m/s just prior to impact would be the most representative load case. A finite element analysis (FEA) of the proposed impact test on a specimen canopy was completed. Thereafter, the actual pendulum impact test was conducted to demonstrate the applicability of the proposed test procedure as well as the correlation with the FEA. It was shown that both FEA and actual testing are viable qualification procedures and that they can in fact be used to reliably assess the strength of the canopy. Finally, the outline of a test specification was developed and proposed, which can be used by national regulatory institutions to assess the structural integrity of commercially manufactured canopies.

The results of 17 patients with type III open tibial fractures were judged retrospectively by using the Guides to the Evaluation of Permanent Impairment. The fractures were divided into types IIIA (N = 7), IIIB (N = 5) and IIIC (N = 5) according to Gustilo et al. (1984). The impairment scores of these patients were compared with those after a through-knee amputation (36 per cent impairment) or a below-knee amputation (28 per cent impairment). The average impairment scores of the three groups were: IIIA 7.1 per cent, IIIB 19 per cent, IIIC 18.4 per cent. The impairment score of salvaged type III open tibial fractures, for each group, IIIA, IIIB and IIIC, was lower than that after a below-knee or through-knee amputation.

Closed reduction of a greenstick fracture of the forearm in a child of 9 years was complicated by interposition of the deep flexor tendon of the third, fourth, and fifth fingers in the fracture gap. Undelayed release of the tendon resulted in a complete functional recovery.

Unlabelled: In a retrospective study, the results of 39 patients with fresh unilateral femoral shaft fractures were studied: 19 had been treated with an AO interlocking nail and 20 with an AO plate. The preoperative characteristics of both groups were similar. The interlocking nail procedure took significantly longer (P = 0.002, Wilcoxon's test) and was associated with technical faults in seven patients. Full weight-bearing was allowed significantly earlier (P = 0.001, Wilcoxon's) in the interlocking nail group. Delayed union was observed in three patients in the plate osteosynthesis group but was not encountered in the interlocking nail group. Cancellous autogenous bone grafting was performed seven times during or after plating, but was not necessary in the interlocking nail group. Two cases of osteitis arose after plating and none after interlocked nailing. At follow-up, one patient in each group was suffering from serious complaints., Conclusion: The interlocking nail procedure took longer than plating, but allowed earlier full weight-bearing. The final results were similar in both groups of patients.

To investigate the outcome of conservative treatment, with and without closed reduction, 45 patients with fractures of the fifth metacarpal neck were evaluated 1 to 5 years after the initial injury. Radiographs were then taken to compare angulation and length with the original radiographs. The range of motion of the joints of the little finger was measured and the grip strength was assessed. The effects of malrotation on cosmetic appearance were observed, as were any signs of dystrophy. Finally, the patient's subjective opinion was obtained. Disability due to the injury was found in three patients while two others had moderate symptoms during daily activities. There seems to be little indication for closed reposition or operative treatment.

In a retrospective study 101 patients who underwent surgery for a parotid mass were evaluated. The different diagnostic modalities (sialography, ultrasound, needle biopsy and frozen section) are described and discussed. Eighty-one tumors proved to be benign, of which 56 patients had a pleiomorphic adenoma, ten of them had a recurrent pleiomorphic adenoma, all after an enucleation, which again proved to be an inadequate operation for a parotid mass. The 20 malignant parotid tumors had a poor clinical outcome. Of the 18 patients with a malignant primary parotid tumor three showed a local recurrence and five metastatic disease within five years. The morbidity of parotid surgery is mainly due to post-operative facial nerve weakness (30%), which is mostly reversible, and the Frey syndrome (10%).

Partial ileal bypass surgery in homozygous Watanabe heritable hyperlipidemic (WHHL) rabbits resulted in a decrease of low density lipoproteins (LDL)-cholesterol from 14.2 +/- 2.4 to 7.0 +/- 1.2 mmol/l. To investigate the effect of partial ileal bypass on receptor-mediated and receptor-independent LDL catabolism, turnover studies were performed of radiolabeled native LDL and chemically modified LDL (methyl-LDL) in WHHL rabbits after partial ileal bypass, in WHHL control rabbits, and in New Zealand White ("normal") rabbits. The plasma LDL pool in WHHL control rabbits was increased 10-fold. The receptor-mediated LDL clearance was essentially zero in WHHL rabbits, both in controls and after ileal bypass surgery; the fractional catabolic rates for total LDL were equal in both WHHL groups and were also similar to that for methyl-LDL in the normal rabbits. Seventy percent of the total LDL clearance in the normal rabbits occurred via the LDL receptor pathway. In the animals with a partial ileal bypass, the plasma LDL-protein pool was appreciably lower than in WHHL controls (41.6 +/- 5.7 vs 73.4 +/- 9.9 mg/kg, P less than 0.02). The absolute catabolic rate was almost 50% lower in the PIB group (21.4 +/- 2.0 vs 40.0 +/- 7.5 mg X kg-1 X day-1, P less than 0.02). These results indicate that the decrease of LDL after partial ileal bypass surgery in WHHL rabbits is the result of a reduced production rate of LDL.

The effects of the calcium antagonist, nifedipine, on atherogenesis were investigated in WHHL rabbits, a unique animal model for human familial hypercholesterolemia. Nifedipine, in a daily dose of 40 mg, was fed orally to 9 rabbits over a period of 26 weeks, resulting in serum concentrations of between 740 and 1370 ng/ml. Rabbits were killed at an age of 40 weeks and atherosclerotic plaque formation in various aortic segments was quantified. Atherosclerosis was most pronounced in the aortic arch and the thoracic aorta, plaques covering, respectively, 59 +/- 17% and 17 +/- 9% of total vessel area. These results are similar to those observed in a control group, which received the same diet and no nifedipine and displayed lesions on 62 +/- 19% and 21 +/- 13% of total area of aortic arch and thoracic aorta, respectively. Although variations in plaque area between WHHL rabbits are large and thus preclude the observation of small effects, the efficacy of nifedipine as an anti-atherogenic agent in rabbits with hereditary hypercholesterolemia appears questionable.

The effect of 3-hydroxy-3-methylglutaric acid (HMG) on serum cholesterol levels was investigated in Watanabe heritable hyperlipidaemic (WHHL) rabbits. Oral administration of HMG resulted in a reduction of serum cholesterol by 39%. Bile acid drainage, by means of either cholestyramine medication or partial ileal bypass (PIB) surgery, also led to significant reductions in circulating cholesterol, by 35 and 59% respectively. Intraperitoneal injection of HMG after PIB surgery further reduced serum cholesterol by 35%. Fibroblasts from the WHHL rabbits did not show high-affinity binding, uptake or degradation of 125I-labelled low density lipoprotein (LDL). The working mechanism of these lipid-lowering lowering therapies in WHHL rabbits is discussed in relation to recent literature. The significant reductions in circulating cholesterol induced by HMG warrant further investigation into the use of this compound in the management of familial hypercholesterolaemia.

Prophylactic mechanical ventilation with PEEP of patients with severe injuries prevents or attenuates the clinical manifestations of ARDS. Also, operative stabilization of all major fractures appears to be beneficial in reducing the incidence of ARDS. Primary external or internal fixation of all unstable long-bone fractures combined with prophylactic ventilation is safe and well tolerated, and allows for optimal nursing of the patient. In a group of 58 severely injured patients, treated accordingly to these principles, late death from remote organ failure due to sepsis--which is the main cause of death in multitrauma patients treated with delayed osteosynthesis or conservative fracture treatment--did not occur. Prophylactic mechanical ventilation with PEEP resulted in a significantly lower incidence of ARDS.

The treatment and results of a retrospective study are presented on 23 patients who underwent surgical treatment for a fracture of the base of the thumb metacarpal. The 12 patients with a Bennett fracture were not found to be suffering from limitations in their daily activities, work, sport or hobbies. In the majority of cases an anatomical or almost anatomical position was achieved and maintained using closed reduction and extra-articular Kirschner wire fixation. Two of the seven patients with a Rolando fracture were found to have complaints which gave rise to limitations in the above-mentioned activities. The results of the four patients with an extra-articular fracture were good. Owing to the favourable results obtained with closed reduction and Kirschner wire fixation, this technique should be given preference over the more difficult open reduction and internal fixation.

At age of 40 weeks, 9 WHHL rabbits were necropsied as a baseline control group for evaluating aortic and coronary atherosclerosis. An additional 18 WHHL rabbits of the same age underwent either a partial ileal bypass (PIB) or a sham operation. Serum cholesterol concentrations were significantly lower in PIB rabbits than in sham-operated rabbits, mean postsurgical values being 7.9 +/- 2.3 mmol/l and 13.2 +/- 2.4 mmol/l, respectively. This effect was mainly due to a lower LDL-cholesterol concentration. Serum triglycerides remained unaffected. Thirty weeks after surgery the PIB and sham rabbits were necropsied and atherosclerosis was evaluated. Progression of atherosclerotic plaque size in the sham group was most prominent in the aortic arch. PIB largely prevented this progression. The frequency of plaque complications in the aortic arch also increased in the sham groups. Here, no significant improvement was found in the PIB group. Extensive examination of the heart showed some affected coronary arteries in every 40-week-old WHHL rabbit. Progression of coronary atherosclerosis during the postsurgical period was small in both sham and PIB groups. However, while PIB did not affect the plaque size, it significantly reduced the number of coronary arteries affected.

The effectiveness of partial ileal bypass (PIB) as a counter-measure against atherosclerosis was evaluated in WHHL rabbits. The effects of PIB and sham operation, each performed in five animals, on serum lipids, lipoproteins and plaque formation were investigated. PIB resulted in an immediate and sustained decrease of 52% (range 29-67%) in serum cholesterol, while sham operation had no effect. The main reduction was in LDL cholesterol; VLDL-cholesterol was lowered to a lesser extent. PIB also appeared to change the electrophoretic behaviour of total serum, very low density and low density lipoproteins. Plaque formation, measured 30 weeks after operation in various aortic segments and arteries, was significantly reduced after PIB. It is concluded that an induced lowering of serum cholesterol can prevent atherosclerosis in WHHL rabbits. Also, these animals must be considered as a model for the receptor-defective cellular phenotype of homozygous familial hypercholesterolemia, not for the receptor-negative type, which is the only truly genetically homozygous form.

This case history describes a 70-year-old female patient with a malignant fibrous histiocytoma (MFH) of the breast with secondary involvement of the skin and axillary lymph node metastases. We think that in the case of a MFH of the breast a radical or modified radical mastectomy should be pursued instead of a simple mastectomy.

From 1970 to 1985, 49 patients were operated for traumatic aortic rupture (TAR) in 2 university hospitals. Protection of distal ischemia was performed 31 times with a left heart bypass (LHB), 5 times with a heparin coated shunt and, 13 times using simple aortic cross-clamping combined with pharmacological vasodilatation. Total mortality was 17 out of 49, 5 during and 12 after the operation, 2 of them being directly related to systemic heparinization during LHB. In the LHB and shunt groups there was one postoperative paraplegia out of 35 patients, while 4 from the 13 patients operated without a shunt developed paraplegia. If risk factors such as long cross-clamping time, hypotension, extensive laceration of the inner curvature of the aorta, or cross-clamping of the aortic arch at a high level are anticipated, LHB or the shunt technique must be considered to avoid paraplegia. A repair without a shunting procedure should be limited to those cases in which the individual surgeon believes that he can do the operation within 30 minutes aortic cross-clamping time.

The effect of delayed internal fixation in closed uncomplicated fractures of the femoral shaft was studied by comparing 40 patients from a hospital where this fracture was principally treated within 24 hours of the injury, with 46 patients from another hospital where this type of fracture was principally treated after a mean period of 13 days in skeletal traction. The two groups of patients were similar with regard to age, level of fracture, type of fracture and incidence of comminution. All fractures were treated by stable internal fixation. In the group treated by early operation considerably longer AO plates were used. Although delayed fixation resulted in more callus and although secondary bone healing was more frequent than in the group with early internal fixation, no difference in the rate of union of the fractures could be demonstrated.

The results of 20 conservatively treated elbow dislocations were retrospectively studied in 20 adults older than 16 years. After an average follow-up of 5 1/2 years (range 2-10 years), 16 patients (80%) had good or excellent results. Only two patients with neurological lesions showed poor results. According to the literature instability is always present after reduction of elbow dislocations. The conservatively treated patients of the present series showed no serious problems with long-term elbow instability at follow-up. In case of simple elbow dislocations instability after reduction does not form an indication for surgical treatment.

Unlabelled: In a group of 316 children with 318 femoral shaft fractures, 28 had been treated operatively (8.8%). Twenty children treated with plate-osteosynthesis came for follow-up. The indications for operation were polytrauma (6 X), unacceptable position after conservative treatment (6 X), severe head injury (3 X), serial fractures of the same limb (3 X) and open fractures (2 X). The average follow-up after trauma was four years and six months. Direct postoperative complications were a transient peroneal nerve palsy and a broken plate. In 17 children the difference in leg length was less than or equal to 1 cm. One boy with serial fractures of the same limb had an overgrowth of 3.3 cm and problems during walking., Conclusion: plate-osteosynthesis was a good method of treatment in this study on 20 children with femoral fractures and accompanying complicating conditions.

In a retrospective study 20 children with a medial epicondyle fracture of the elbow were evaluated. Possible pitfalls in diagnosis are described. The fate of the fragment after conservative as well as after operative treatment cannot be predicted. Nevertheless, final results were satisfactory.

The effects of bile acid drainage on serum cholesterol levels have been investigated in Watanabe heritable hyperlipidemic rabbits, a unique model for homozygous familial hypercholesterolemia. Cholestyramine medication lowered serum cholesterol concentrations with 38%, while a 33% and a 50% small bowel bypass resulted in a decrease of 56 and 48%, respectively. Cholestyramine treatment after either bypass induced a minor additional fall in serum cholesterol. Ileal bypass and ileal resection were equally effective in reducing serum cholesterol. These results indicate the necessity for further investigation into the potential of bile acid drainage as a therapy in homozygous familial hypercholesterolemia.

Aim of the present study was to compare an alimentary and a hereditary rabbit model for hypercholesterolemia. Serum lipids, serum lipoproteins and distribution and prevention of atherosclerotic plaque formation were studied in (1%) cholesterol-fed NZW rabbits and both heterozygous and homozygous WHHL rabbits. Cholesterol-fed NZW rabbits showed a hypercholesterolemia without hypertriglyceridemia, caused by accumulation of a spectrum of cholesterol ester-rich beta-migrating lipoproteins with a relatively low density. The WHHL rabbits displayed both a hypercholesterolemia with an elevation of LDL, and a hypertriglyceridemia. The hypertriglyceridemia in the WHHL homozygotes was due to accumulation of VLDL remnants and in the heterozygotes to a slight rise in normal pre-beta VLDL. Despite the pronounced quantitative and qualitative differences in lipoproteins, the location and extent of atherosclerotic plaques which had developed after 13 weeks cholesterol-rich diet in NZW rabbits and in 10 months old homozygous WHHL rabbits, was quite similar. Partial ileal bypass surgery lowered serum cholesterol in all three groups and also prevented atherogenesis.