Certain features of the sagging rope sign recently analysed by Apley and Weintroub (1981) are examined in detail. Evidence is presented to show that the line is a radiological shadow cast by the lateral edge of a severely deformed femoral head rather than a condensation of the spongiosa within the neck. An explanation is offered to explain the common association of the presence of this radiological sign with premature epiphysial fusion.

1. The fibrillar networks of adult human articular cartilage, taken from femoral and acetabular specimens, have been systematically examined by scanning electron microscopy. The internal structures revealed by rupturing the tissue were compared with published findings from transmission electron microscope studies.

2. Though this technique demonstrated the internal fibrillar appearance of cartilage to a remarkable degree, it had several attendant limitations. On final drying, specimens generally exhibited shrinkage which varied within wide limits; this could have altered the internal architecture to some extent. In addition, the rupturing technique, which at the time of this investigation was the only satisfactory method of revealing the fibrillar cartilage structure, may well have had a great influence on the fibril orientations.

3. The fibrils revealed no characteristic collagen periodicity and were considerably thicker than those observed by transmission electron microscopy. It is suggested that a coating of mucin on the collagen fibrils might account for this.

4. At low magnifications the torn layers in the fractured surfaces extended radially from the calcified zone and turned obliquely at or near the articular surface to merge with the distinctly layered superficial zone, thus forming arcade-like structures. That these were not artefacts produced by the fracturing technique was shown by their similarity to the classical arcade pattern of light microscopy. However, the factor which governed the direction of these planes of weakness, be it collagen, mucopolysaccharides or cells, could not be satisfactorily determined.

5. At higher magnifications only three regions of distinct fibrillar organisation could be identified: 1) a surface layer consisting of a random fibrillar network; 2) a superficial zone composed of layers of fibrillar network, intersecting and overlapping in planes parallel to the surface; and 3) elsewhere below the superficial zone a network of virtually random fibrils which extended to the calcified region with apparently little variation in thickness or density. There was little variation from this pattern even in aged fibrillated specimens.

6. At the lower magnification range the scanning electron microscope has revealed the arcade pattern described by light microscopy, while at the higher magnifications the fibrillar organisation as seen by scanning electron microscopy correlated well with the concepts developed by transmission electron microscopy, that is, a random network of fibrils overlaid at the articular surface by a membrane-like system of bundled fibrils.

7. A possible role in the transmission of joint forces is outlined for the above fibrillar organisation.

1. The methods of treating flayed limbs are enumerated, with mention of the reasons against conserving the injured skin.

2. The reasons for conserving the injured skin are presented and they are backed by the results in the patients described.

3. The factors that may influence the survival of injured skin are discussed, and the indications for, and methods of, conserving injured skin are described.

1. Radiological and histological observations of the tissue changes resulting from the implantation of various metals in the long bones of dogs are recorded.

2. Of the metals employed, tantalum, Vitallium, alloys "C" and "S" and F.M.B. steel were inert; silver and mild steel were reactive; F.S.T. steel occupied an intermediate position.

3. A correlation has been demonstrated between the anodic back E.M.F., the weight loss due to corrosion and the histological changes produced.

1. Attention is drawn to that type of rigid congenital flat foot in which the talus lies vertically instead of horizontally.

2. This deformity is rare, but if not treated successfully leads to an ugly, painful foot in adolescence.

3. The experience of five patients forms the basis of the present preliminary account. One adolescent and two young children under the age of five were treated unsuccessfully by both conservative and operative measures. More recently in two children with bilateral deformity open operation has been successful in restoring the shape of the foot.

4. The operation is essentially a reduction of a subluxation at the talo-navicular and subtalar joints. It entails freeing the head of the talus sufficiently to allow it to be lifted dorsally and laterally. The talus is then anchored in position by transplanting the distal end of the peroneus brevis tendon through the neck of the bone.

1. The literature dealing with the reaction of tissues to metals has been briefly reviewed and discussed.

2. It is suggested that the "anodic back EMF" of metals, under the conditions of the experiment, is a measurable electrical quantity which can be correlated with their behaviour in tissues.

3. Details of the method for obtaining this "anodic back EMF" are given.

4. A correlation between the "anodic back EMF" and the loss of weight due to corrosion in vitro has been demonstrated.

5. The inertness of eighty-seven metals has been classified by this method.

6. It must be emphasised that these results are based on in vitro experiments only. In vivo experiments are in progress and the results will be published in due course. Preliminary work suggests that there is some correlation between the ABE and the behaviour of metals in tissue (Hickman 1953).

It has been fascinating to trace the gradual erection of the British edifice of orthopaedics, and nostalgic to recapture a memory, however fleeting, of some of the figures who built it and taught us so much of our sum of knowledge half-way through the twentieth century—the remarkable spell of Robert Jones, the lofty, ascetic Tubby, the pugnacious Openshaw, the forceful and enthusiastic Hey Groves, the earnest but irascible Laming Evans, the equable and thoughtful Elmslie, the restless and exuberant Trethowan. It is always tempting to conclude: "those were the days." It is probably wise to do no more than record the events and leave judgment of progress to a later century. But we are being judged already and not always kindly or even truthfully. We are justified surely in priding ourselves on what has already been achieved, and on the service that orthopaedic surgery now gives to the community and promises for the future. In concern for this aspect of our work we have perhaps tended to neglect our capacity for basic research. But we are aware of this shortcoming, as witness our closer relationships with research departments of universities and royal colleges, and our increasing contacts with colleagues in the basic sciences. Finally, apart from the most intellectual snob and the pessimistic cynic, all must surely rejoice at the enthusiasm, industry and ability of our young colleagues—the orthopaedic surgeons of to-morrow.

1. The history of the genesis of the Putti-Platt operation for habitual dislocation of the shoulder is outlined so far as it is known.

2. The operation is described and briefly commented upon.

3. Since there is both gleno-labrial detachment and defect in the humeral head successful treatment depends upon: i) a block to the exit of the humeral head in front and ii) limitation of external rotation movement.