Three articles, published in the Virchow archives in 1862 and 1863 [27,28,29] are referred to as the beginnings of the HVL formulation. Unfortunately, they are all written in a very complicated and lengthy manner and it is not easy to interpret their content accurately.

Volkmann was the first to publish his article (1862) [27] focused on bone growth, which, however, was based only on an analysis of the literature and his own clinical observations, rather than on experiments. Most authors who dealt with HVL, reduced Volkmann´s article to a mere analysis of the growth of the human skull [4, 7]. However, Volkmann addressed more issues in his study and his opinions may be summarized as follows:

Growth of bone and maintenance of its shape must be controlled by certain laws.

One of the laws states that during growth, bone shape changes mostly by periosteal and by simultaneous intramedullary apposition.

A child’s skull has a sharper curvature than an adult skull. A child´s skull grows in such a way that “…there is never any overstressing of the bone… the periosteum adds new layers, while the increasing pressure from the inside on the previously formed bone leads to its atrophy”. Thereby, the internal processes taking place in the bone also influence its external shape (Fig. 1).

Fig. 1

The growth of the human skull, after Volkmann [26]. a – change in the skull shape: S – curvature of an adult skull, s – curvature of a child´s skull, a-b – shift of the double contour of parietal bone during growth; b – change in skull curvature: a, b,c, d – curvature of individual bones forming the calvaria of a child´s skull, e – the double contour of an adult, f, ff, f – cross-sections of skull sutures, which are the regions of the minimal periosteal apposition of the bone

The change in the shape of the bone occurs for various reasons. An example may be genu valgum and genu varum, when the physiological axis can be restored by application of plaster fixation and splints for 6 months. The bone shape may be changed also due to bending, or shifting, of the whole articular surface, e.g. in osteoarthritis, or bending of ribs in scoliosis. Other causes include for instance inactivity (senility, palsy etc.).

Bone elasticity and calcium metabolism are tools to change gradually the bone shape.

A bone grows interstitially and, as a result, it may enlarge or shrink (Fig. 2).

Fig. 2

Interstitial bone growth of long bone after Volkmann [26]

Fractures or necroses may result in overgrowth of the extremity, caused by inflammation stimulating a higher production of cells in the nearby epiphyseal cartilage. Conversely, certain inflammations, suppurations, or synostoses cause shortening of the bone.

Another study on this topic was published by Hueter, in 1862 [28], a few months after Volkmann, the second part of which was published as late as in 1863 [29], and is referred to in the literature only rarely [4]. In the first part of his study, Hueter dealt with articulation between the tibia and talus, and also with analysis of the subtalar joint in both children and adults (Fig. 3). Based on his observations, he deduced that the shape of the articulating bones resulted primarily from a relatively higher growth rate of those parts of the bone that were exposed to a lower compression load. In the other part of the article, the author focused on knee and hip joints. He discussed in detail the shape of the articular surfaces and noticed that the femur grows much more at its distal end. He described the division of the common cartilaginous epiphysis of the proximal femur into two parts. Worth noting is the part where, referring to Duhamel [30], Hunter [11] and Flourens [12], he argued with Volkmann about interstitial bone growth (IBG). Hueter was very cautious about the theory of interstitial growth and claimed that further discussion was needed in this direction.

Fig. 3

Original drawings of talus and calcaneus used by Hueter to study bone growth in the region of the subtalar joint [27]

One year later (1864), Hueter published a study on mandibular growth in which he again discussed Volkmann’s views [31]. This article, however, is not mentioned in the HVL literature.

Note

Mandibular growth fascinated many prominent anatomists and surgeons for many decades [11,12,13,14]. Unfortunately, it was not a suitable bone for studying the general principles of bone growth, as mandibular growth is complicated and could be most easily explained by IBG.

Another source, often referred to by authors dealing with HVL [4, 7], is Volkmann´s chapter Die Krankheiten der Bewegungsorgane in the monumental textbook of surgery “Handbuch der allgemeinen und speziellen Chirurgie“ published in 1865–1882 by Theodor Billroth (1829–1894) and František Piťha (1810–1875). However, individual authors differ on the year of publication, stating the years 1865 [7], 1869 [4] or 1882 [3]. We have discovered that 1865 is the year of the first edition [32] and 1882 of the second edition [33], although it is mentioned in neither book title. The year 1869 was obviously a mistake.

In both editions, Volkmann´s chapter is included in Band II, Abteilung II. Here, in Chap. 37 ”Bone hypertrophy and atrophy”, the author briefly states on pages 350–351 that hypertrophic conditions may include “abnormal lengthening of the bone due to absence of physiological compression load, an analogue of the much better known and much more common pressure atrophy, or pressure usuration: increased growth of the radius in length after its dislocation in the humeroradial joint…” [32, 33].

On page 333, in both editions, Volkmann mentioned bone growth. He stated that it occurs in three ways. Responsible for longitudinal growth is the cartilaginous disc between the epiphysis and metaphysis. Cartilaginous cells proliferate on the epiphyseal side and turn into bone cells on the diaphyseal side. Bone growth in width is the function of the periosteum. Widening of the medullary canal occurs by endosteal resorption. On pages 692–700 of the same chapter, Volkmann focused on the effect of compressive load on the shape of articular surfaces: “Anomalous difference in pressure results in asymmetric growth of the articular ends. Greater pressure retards the growth, lower pressure accelerates it“.

No mention was made of IBG there, which contradicted the theory of interstitial growth that he had published in 1862 [27]. Volkmann defended the IBG theory again in 1870, stating that a bone grows from the physis (Epiphysenfuge) only minimally [34]:“…I am convinced that the great long bones grow in length due to interstitial growth, and involvement of the growth cartilage comes into consideration only minimally.“. Such a fundamental change in his views is hard to explain, perhaps only by the fact that in the official textbook of surgery he presented the majority opinion of that time, whereas in the two articles he presented his own standpoint.

A careful analysis of all Volkmann´s and Hueter´s texts has shown that none of their publications [27,28,29, 31,32,33,34] was based on experiments, but merely on the data in the literature and their own anatomical and clinical observations. With some exaggeration it may be said that both authors, and particularly Volkmann, used incompatible arguments. They did not deal at all with the effect of pressure on the growth plate and mentioned this structure only marginally. They differed on a number of aspects, such as interstitial growth, and shared only the opinion that increased pressure retards and decreased pressure accelerates bone growth.

The statement by Willy et al. [7] concerning Volkmann saying that he also ‘‘suggested alterations in the growth of long bones as a result of tension and compression on the epiphyseal plate..’’, is a deep historical error. The way HVL is presented today [2, 4, 7, 9] is the result of gradual distortion of the original facts passed on from one article to another, when most modern authors do not know the original texts.