The abstracts were prepared on Mr J.

The abstracts were prepared on Mr J. H. Clegg. Correspondence should be addressed to him clo the BOA, Royal body of Surgeons, 35-43 Lincoln's Inn Fields, London WC2A 3PN

ANALYSIS OF ACUTE PAEDIATRIC ORTHOPAEDIC ADMISSIONS IN A DISTRICT GENERAL HOSPITAL

Dr V B Srinivasan and D A Jone Department of Orthopaedics. Morriston Hospital, Swansea

Summary: An analysis of the data, of all the 872 acute paediatric orthopaedic admissions in a paediatric surgical ward, in a district general hospital, throughout a two year period.(Oct 1992 - tribe 1994) showed that:

1 Orthopaedic admissions (582) was more than twice the number of the total of all other admissions.

2 forward average, each orthopaedic case had a stay of 424 days.

3 Trauma admissions were more in number between April to September (more sunshine hours).

4 Trauma was more used by all in boys.

5. Fractured forearm (517%) was the largest cluster in traumatic admissions.

6 Non traumatic admissions formed 157 % of all, acute admissions (917% of these were transient synovitis of the hip).

Our conclusions are as follows:

1 The fact that orthopaedic admissions cover more beddays, coupled with the fact that traumatic admissions are pensioner in summer months, leads to the logical conclusion that more beds will be occupied in summer Contrarily in winter, more beds are confine to be vacant. Instead of following a policy of fixed bed toughness throughout the year in so units, if a flexible framework is followed. it may be more useful economically.

2 lt can be seen that more than two-thirds of all acute admissions ensue from orthopaedics. Considering the high incidence of trauma and head injuries coming into the ward, it will be preferable to have all the staff suckles in such wards trained not merely in child care, but also in trauma.

CAM improvement OF FEMORAL AND HUMERAL HEADS FROM PRE AND NEO-NATAL RABBITS: A rule FOR INVESTIGATING THE FORMATION OF THE SECONDARY middle OF OSSIFICATION

N M P Clarke, H I Roach, J E Baker Southampton General Hospital, Southampton Many affairs occur concurrently during the initiation of the secondary ossification middle in the cartilaginous epiphyses of drawn out bones. We have investigated the chronology of interactions between the vascular connected view and epiphyseal chondrocytes by culturing explanted heads of thigh-bones and humeri from pre and neonatal rabbits forward the chorioallantoic membrane (CAM) of growing chick embryonates We confirmed that on the whole, the epiphyseal cartilage was resistant to vascular invasion, whereas the physeal sprouting plate was resorbed. However, recently made known CAM-derived cartilage canals occasionally penetrated within the articular surface. This caused death of those chondrocyte in the immediate vicinity of the canal yet no further reaction. If explants already contained a bony epiphysis and were halved prior to refinement CAM-derived vessels were attracted to the spongiosa. From there they pushed into the uncalcified cartilage. indicating that calcification was not a pre-requisite for vascular invasions. Where at least sum of two units vessels were in apposition, a recently made known pseudo-ossification centre was initiated: chondrocyte became hypertrophic and the matrix calcified. This proposes that cumulative release of diffusible factors from more than united vessel was the trigger for chondrocyte hypertrophy which, in use led to the initiation of the bony epiphysis. CAM agricultures thus provide an experimental archetype for both the quiescent angiogenesis of cartilage canal formation and the reactionary angiogenesis associated with chondrocyte hypertrophy from exploiting the different anatomy of CAM-derived vascularity, affairs which occur concurrently in vivo can be spacially separated in CAM agriculture

Key Words: cartilage canal, secondary ossification, chorioallantoic membrane, angiogenesis

A CLINICAL AND RADIOGRAPHIC research OF THE EFFECTS OF OSTEOCHONDROMAS upon THE GROWTH PLATE

D E Porter, F Lopez A H R W Simpson Oxford

Introduction: Hereditary Multiple Exostoses (HME) yields variable effects on stature and limb deformity. through many years this has l to its classification by dint of some experts as a skeletal dysplasia. At a molecular of the same height this classification would suggest the neighborhood of an inherited fieldchange in all confined apartments of at least one tissue involved in skeletal increase Recent advances in molecular biology have identified that the 'EXT' tumour suppressor gene family is responsible for HME Since tumour suppressor gene typically occasion structural anomalies through clonal expansion of single mutated small rooms this would conflict with the molecular basis for classification of HME as a skeletal dysplasia.

Aims: To investigate whether an drift of osteochondromas on growth plate function can be identified from one side analysis of clinical and radiographic changes in HME This may propose a neoplastic aetiology (clonal expansion effect) rather than a dysplastic aetiology (field change effect) for osteochondromas.

Design: A comparative clinical and radiographic investigation of forearm osteochondromas and bone amplifications in children with HME.