The material at present on hand is therefore sufficient, if not to solve the problems of the disease, at least to make out a tolerably complete clinical history.
SYMPTOMS.—The early appearance of the morbid symptoms is the first striking peculiarity of the disease. Out of 88 cases whose records I have analyzed, 35 must be considered congenital, since some degree of paresis was observed from the time the child first began to walk;16 and the effort at walking was unusually late, being deferred till two, three, or even four years of age. In 21 other cases the first symptoms of the disease declared themselves between the ages of three and six17—at the age of seven 8 other cases began;18 between nine and ten, 7 cases;19 between ten and sixteen were 8 cases;20 finally, in 7 cases, of which 2 are more than doubtful (cases Barth and Müller), the disease seems to have begun in adult life.21 Thus, 57 cases, or rather more than two-thirds of the whole number, began before the age of six.
16 These cases are the following: Meryon, Lond. Med. Gaz., 1852 (5 cases); Partridge, ibid., 1847; Duchenne, Électris. local., 1861; Kaulich, Prager Vierteljahr., 1862, quoted by Friedreich; Spielmann, Gaz. méd. de Strasbourg, 1862, quoted by Friedreich; Duchenne fils, Archives gén., 1864 ("De la Paralysie atrophique graisseuse"); Griesinger, Archiv der Heilkunde, 1864; Sigmund, Deutsches Archiv für klin. Med., Bd. i. Heft 6; Wernich, ibid., Bd. ii. Heft 2, 1866; Benedikt, Elektrotherapie, Wien, 1868; Balthazar Foster, Lancet, 1869; Barth, Archiv der Heilkunde, xii. 2, 1871; Chrostek, Oesterreich Zeitschrift für prakt. Heilkunde, No. 38, 1871, quoted by Friedreich; Pekelharing, Arch. Virch., 1882, Bd. lxxxix., quoted by Friedreich; Knoll, Wien. Medizin Jahrbuch., 1872; Friedreich, Pseudo-hypertroph. der Musc., 1878, p. 291; Duchenne, Archives gén., 1868 (7 cases); Hammond, Treatise Nerv. Dis.; Gowers, loc. cit. (5 cases); Ross, Treatise Nerv. Dis., 2, 204.
17 Cases by Eulenburg, Allgemeine Med. Central Zeitung, Berlin, 1863, quoted by Friedreich; Rinecker, Verhand. du Phys. Med. Gesellsch. zu Wurzburg, 1860, quoted by Friedreich; Heller, Deutsches Archiv f. klin. Med., Bd. i. H. 6 (2 cases); Wernich, ibid., Bd. ii., 1866; Lutz, ibid., Bd. iii., 1867; Benedikt, loc. cit. (5th and 6th cases); Russel, Med. Times and Gaz., 1869 (3d case); Duchenne, loc. cit. (2d, 3d, 6th, 12th, 13th cases); Hammond, loc. cit.; Gowers, loc. cit. (6 cases).
18 Cases by Eulenburg and Cohnheim, Beitr. klin. Woch., 1865; Seidel, Atrophia Musculorum Lipomatosa, 1867; Heller, loc. cit. (2d case); Wagner, Berl. klin. Woch., 1866 (8 cases); Benedikt, loc. cit. (1st case); Duchenne, loc. cit. (9th case); Gowers, loc. cit. (7th case).
19 Seidel, loc. cit. (1st case); Coste and Gioja, Schmidt's Jahrb., Bd. xxiv. S. 176; Spielmann, Gaz. méd. de Strasbourg, 1862; Boquette, Inaug. Dissert., Berlin, 1868; Russel, loc. cit. (2d case); Rakowac, Wien. Mediz. Wochen., 1872; Brieger, Deutsches Archiv f. klin. Med., Bd. xxii., 1878; Pepper, Philada. Med. Times, 1871.
20 Lutz, loc. cit. (2d case); Ross, loc. cit., p. 190 (observed when adult); Hoffmann, Inaug. Dissert., Berlin, 1867; Russel, loc. cit. (1st case); Gowers, loc. cit. (18th and 20th cases).
21 Benedikt, loc. cit. (2d and 3d cases); Dyce Brown, Edin. Med. Journ., 1870; Eulenburg, Archiv Virch., Bd. xlix., 1870; Martini, Centralblatt für Med. Wissensch., No. 41, 1871; Barth, Archiv der Heilkunde, xii. 2, 1871; Müller, Beit. zur path. Ruckenmarkes, 1871.
The symptoms are of three kinds: 1st, those dependent on alterations in the function of the affected muscles; 2d, changes in the appearance, consistency, and electrical reaction of these same muscles; 3d, deformities resulting from their structural alteration.
The first muscles invaded are invariably the gastrocnemii,22 and therefore uncertainty of gait is the first symptom observed. The child is usually backward in learning how to walk, even when two, three, or four years intervene between this acquisition and the first decided appearance of the disease. In the unquestionably congenital disease the act of walking is always imperfectly performed, and the original imperfection gradually deepens into a noticeable uncertainty of gait, and finally into real paresis. It is noticed that the child falls very frequently—at first only when running, afterward even while standing. He then begins to experience difficulty in going up stairs: pulls himself up by the bannisters, and usually drags one leg completely. After a while it becomes quite impossible for him to go up stairs except on his hands and knees.