1. A series of 154 patients who underwent anterior cervical discectomy and fusion has been studied. A detailed analysis of the first eighty-four patients who have been observed for periods of from one to eight and a half years is described. In sixty-eight patients the fusion was done with a keystone type of graft, in seventeen by a dowel (Cloward) graft.

2. Despite a preponderance of multiple level fusions in the keystone series, clinically better results (80·8 per cent excellent or good) were found in this group than in the dowel group (64·8 per cent excellent or good).

3. A biomechanical study has indicated the keystone graft to be more stable than a dowel graft under flexion and extension strains as well as lateral bending strain. The graft is more stable the closer it is to the line of "zero velocity."

4. The three cases of non-union all occurred in the dowel group. The high incidence of fusion with the keystone technique is considered to be related to the type of graft, its method of seating, its depth of penetration, its larger surface area and the fact that raw cancellous bone of the adjacent vertebral bodies is in contact with the graft above and below.

1. Tarsal coalition often presents with the clinical picture of a peroneal spastic flat foot, but may present with a painful varus foot and spasm of the tibial muscles.

2. Three cases of tibialis spastic varus foot are described with a calcaneo-navicular bar as the associated anomaly.

3. Complete excision of the bar with interposition of the origin of the extensor digitorum brevis muscle appears to be a satisfactory method of treatment when carried out at a sufficiently early age.

1. Three patients are reported in whom a sudden acute internal derangement of the knee was caused by torsion of a pedunculated portion of the infrapatellar fat pad.

2. The symptoms and signs are described.

3. The pathological changes and the pathogenesis are discussed.

1. Arterial spasm may be expected in any injury resulting in stretch of the arterial system.

2. Excessive traction in the treatment of fractures may well initiate diffuse arterial spasm.

3. In fractures that have permitted shortening of the vascular system for a considerable period, spasm may be initiated when a return to normal length is made.