The management of the length discrepancy requires an early removal of the hemodynamic and metabolic causes for the bone pathology because the likelihood of correction by this vascular operation to the primary lesion is much higher when done during infancy (Table 43.3) [12, 34, 35]. When, however, the long-bone length discrepancy is more than 4–5 cm, the combined approach of an orthopedic procedure and vascular surgery has been generally accepted as the primary strategy. When presented with severe length discrepancy, noninvasive and/or invasive diagnosis procedures should be started even before the age of 3 in order to perform the necessary vascular procedure to correct the pathologic hemodynamics first before it is too late [17]. However, if the vascular cause of the length discrepancy can be contained until the age of 7, orthopedic surgery may then be performed (Table 43.4). The policy of first performing vascular surgery to arrest further abnormal long-bone growth and then subsequent additional orthopedic correction is the treatment of choice. An early aggressive approach is mandatory [9, 30–32].

In the long run, length discrepancy may not represent the underlying problem in these patients. That is why a critical indication should be considered.

Children and young people with a congenital vascular malformation sometimes also suffer mono- or oligoarthralgia of the large joints, mainly of the lower limbs (Table 43.5) (Hauert Disease) [33].

What we notice here is that this includes cases in which destruction of the affected joints occurs early on in childhood, sometimes even before the age of 5, the considerable extent of which stands in extraordinary contrast to the usual complaint of moderate or slight pain. What is also striking is that this joint condition is accompanied only by very marginal inflammatory malformations and that, entirely unlike in primary degenerative joint changes, this type of destruction appears not to show any significant tendency of progression after longitudinal growth is complete. There are no signs of systemic inflammation; rheumatoid factors are consistently negative [5–8]. The vertebra joints appear to be recessed. Based on our experience and knowledge of international literature, this very unusual clinical phenotype is as yet undocumented, so we have provisionally opted for the descriptive term of angiodysplasia arthropathy, or “Hauert disease,” for this set of conditions, with the aim of having it acknowledged as a stand-alone entity.

Vascular malformation on the affected limb makes most patients seriously ill in any case, a major symptom being chronic bouts of phlebitis causing pain and restriction of movement. The clinically visible signs of vascular malformation explain why it is only in later examinations that joint disease is considered as a cause of the symptoms. The vascular malformation alone is capable of compromising joint function so much so that its typical symptoms such as limping, contractures, and painful movement can obscure an arthropathy, which shares the same symptoms. The most striking symptom in patients is a loss of function of the joint, a limp, and possibly a periarticular swelling. Effusion in the knee joint or hemarthrosis is key exceptions. There are generally no lab-based inflammation parameters.

A restriction in movement of the ankle and foot joints can already be detected in newborns. Clinical examination using duplex ultrasound (color-coded ultrasound of the vessels) can quickly diagnose vessel failure (vascular malformation).

We have divided the disease into three degrees of severity depending on the extent of the tissue malformations (Table 43.6).