Forty-five cases in 33 patients of congenital muscular abnormalities causing vascular compression in the popliteal fossa are reported. Three main types of abnormality were distinguished. In the first, one muscle, either the medial head of gastrocnemius or the plantaris, is abnormal. In the second, both these muscles contribute to the problem, whereas in the third type, the semi-membranosus also is abnormal. In some cases an abnormal course of the popliteal vessel(s) is also found. With only a few exceptions, cases reported in the literature fit into this classification. Twelve patients in this series were affected bilaterally but only 5 had the same anatomy in both legs. In only 14 instances, either with thrombosis or with characteristic shifting of the artery, was routine arteriography sufficient for diagnosis; loss of distal pulses during active plantar flexion was necessary in the majority to demonstrate the abnormality. It is suggested that the condition is more common than has been thought.

One hundred and sixteen cases of popliteal aneurysm have been studied. The condition most commonly represents a local manifestation of generalized degenerative arterial disease, either occlusive or dilating. In the latter instance the condition is more often bilateral and there is a higher incidence of aortic aneurysm. Symptoms occur from complications irrespective of the size of the aneurysm. The results of reconstructive operations in false aneurysrns are bad, and unless there is good cause to consider that some form of reconstruction would be successful a lumbar sympathectomy is probably the best treatment. Operation should be advised in all cases with a paten; aneurysm and in those with a thrombosed aneurysm and patent tibia1 vessels. In cases with tibial vessel obstruction due to embolism, clearance can often be effected by the use of an embolectomy catheter to allow distal anastomosis. When a popliteal aneurysm is a manifestation of generalized dilating disease the results of surgery are excellent and long lasting, but if there is generalized stenosing disease the results are the same as after operation for diffuse atherosclerosis. In patients with bilateral popliteal aneurysms, one of which is complicated, the uncomplicated one should probably be operated upon first, although sometimes both may be done at the same session. Sympathectomy seems a worth‐while operation in patients in whom no distal vessel is available for anastomosis, and other proximal reconstructions may be indicated, particularly when diffuse stenosing disease is present.

A study of 864 patients with occlusive disease and 246 with ectatic disease was made with reference to their ABO blood groups. The results confirmed the findings of other workers that occlusive disease and myocardial infarction occur more commonly in group‐A individuals and that blood group O seems to confer some immunity to occlusive disease. There was also a probable correlation between group A and ectatic disease, but belonging to group O did not seem to confer any protection in this disease. It was also found that the incidence of myocardial infarction was much lower in ectatic disease than in occlusive disease. It is suggested that ectatic disease and occlusive disease are two distinct entities.

SUMMARYThe early complications of 445 arterial operations were analysed with reference to the preoperative haemoglobin concentration and platelet count. The hnemoglobin levels were compared with those of 200 non-arteriosclerotic control subjects, and the influence of cigarette smoking on the haemoglobin levels of both groups was assessed. It was concluded that smoking did not affect the haemoglobin levels and that arteriosclerotic patients tended to have higher haemoglobin levels than normal controls. It seems that the higher the haemoglobin or platelet level the greater is the risk of complications at or soon after operalion.

To those who have been responsible for the establishment, maintenance, and development of the centre progress has often seemed too slow and to lag far behind needs. The recommendation of the advisory council of the Head Injuries Rehabilitation Trust was that so far as possible the funds required for what should be acknowledged as a part of the National Health Service should come from the State, and it can be said with due gratitude that the State has emerged with much credit. In writing this article I am but the scribe of many others, without whose imagination, patience, devotion, support, and guidance there would have been nothing to write about. I am confident that those that are not mentioned by name will agree with my expression of thanks particularly to Miss J. E. Drake, secretary, and Mr. S. S. Harkness, treasurer, of the Head Injuries Rehabilitation Trust; Mrs. N. Kimmitt and Mr. H. F. Kinchin, respectively occupational therapist and manager at the work centre; Mr. P. P. Lockhart, group medical social worker; Mr. G. Myers, secretary of the South Birmingham Hospital Management Committee, and his successor, Mr. P. J. Roys; Mr. H. Proctor, surgeon, and Mr. M. B. Rickett, administrator, of the Birmingham Accident Hospital; Dr. Keith Young, deputy administrative medical officer of the Birmingham Regional Hospital Board; and the administrative and nursing staff of the Royal Orthopaedic Hospital (the Forelands) as well as other members of the advisory council of the Head Injuries Rehabilitation Trust and its subcommittees.