1849 he was appointed surgeon in ordinary to the prince consort, and in 1855 surgeon extraordinary, and in 1867 sergeant-surgeon to the queen. For many years Fergusson was the leading operator in London. He was elected to the council of the College of Surgeons in 1861, examiner in 1867, and was president of the college in 1870. As professor of human anatomy and surgery he delivered two courses of lectures before the College of Surgeons in 1864 and 1865, which were afterwards published. He was president of the Pathological Society in 1859–60, and of the British Medical Association in 1873. In 1875 he received the honorary degree of LL.D. from Edinburgh University. He resigned the professorship of surgery at King's College in 1870, but until his death was clinical professor of surgery and senior surgeon to King's College Hospital. He was also a fellow of the Royal Society. He was created a baronet on 23 Jan. 1866, an honour which led to his receiving a presentation from three hundred old pupils, consisting of a silver dessert service worth 400l., at the annual dinner of old King's College men on 21 June 1866. He died in London after an exhausting illness, of Bright's disease, on 10 Feb. 1877, and was buried at West Linton, Peeblesshire, where his wife had been buried in 1860. He was succeeded by his son, Sir James Ranken Fergusson; a younger son, Charles Hamilton, is a major in the army; he left besides three daughters. A portrait of him by Lehmann, painted by subscription, was presented to the London College of Surgeons in 1874, and a replica is in the Edinburgh College of Surgeons.
Fergusson's reputation is that of a brilliant operator and a great ‘conservative’ surgeon. The term conservative surgery, first applied by Fergusson in 1852 to operations for the preservation of parts of the body which would otherwise have been sacrificed, does not denote merely operations which he originated or improved, for James Syme [q. v.] had already been very successful in this line of procedure. But Fergusson extended the principle from the operation of excision of the elbow joint to many others. No portion of the body which could be usefully preserved was too small for him to make efforts to save. Among operations with which his name is specially identified are those for harelip and cleft palate, and operations on the jaws, the excision of joints, notably the hip, knee, and elbow, lithotomy and lithotrity, and amputations of limbs. His skill in dissection, and his careful study of the actions of the muscles which he had to cut through, were of essential importance to his success. In his lectures at the College of Surgeons he was able to speak of three hundred successful operations of his own for harelip. The operation for cleft palate had been largely abandoned till he took it up anew. His manipulative and mechanical skill was shown both in his modes of operating, and in the new instruments he devised. The bulldog forceps, the mouth-gag for cleft palate, and various bent knives attest his ingenuity. A still higher mark of his ability consisted in his perfect planning of every detail of an operation beforehand; no emergency was unprovided for. Thus, when an operation had begun, he proceeded with remarkable speed and silence till the end, himself applying every bandage and plaster, and leaving, as far as possible, no traces of his operation. So silently were most of his operations conducted, that he was often imagined to be on bad terms with his assistants. His punctuality and his hatred of unnecessary waste of time were very marked.
As a lecturer, out of the operating theatre, Fergusson did not shine, owing to his reticence and his imperfect command of abstract subjects; although on points of practice he gave excellent instruction. In the operating theatre his remarks on the cases before him were valuable and instructive. To students he was most kind and generous. He had to sustain much opposition, especially from Syme, but he did not imitate his opponent's mode of controversy; and if on any occasion he imagined he had said or done something to hurt another's feelings, he never rested till he had made reparation in some form.
Fergusson was an excellent carpenter, rivalling skilled artisans. When a student he made himself a brass-bound dissecting case, and in 1834 completed a lithotrite, with a novel rack and pinion, which he used throughout life. He was a good violinist, an expert fly-fisher, and very fond of the drama. His endurance was remarkable; he never seemed tired, and scarcely had a day's illness till attacked by Bright's disease. He was tall, dignified, and of good presence, of genial though keen expression, fond of a joke, and very hospitable. He rendered gratuitous aid to large numbers of clergymen, actors, authors, and governesses. He helped many of his pupils in starting in life, a large number of whom attained eminence as surgeons. He never forgot the face of a pupil.
In some expressions of opinion Fergusson was ill-advised, especially in matters requiring more knowledge of physiology and hygiene than he possessed. His evidence before the royal commission on vivisection, and his relations with homœpathic practitioners, which he was led to modify, are
