A 7-year-old boy was brought to us with swelling of the right knee since 1 year of age. The swelling used to appear suddenly once every two months, would last for a few days and then gradually subside on its own. During the episode, the patient used to have severe pain in the knee joint and was not able to walk. There were no aggravating or relieving factors. There was no history of fever, trauma, bleeding from any other site or swelling of any other joint.

Examination revealed a child with a fluctuating, tender swelling on the medial aspect of the right knee joint (Fig. 1). Movements at the right knee joint were restricted. Further examination revealed a swelling on the medial aspect of the right foot, just in front of medial malleolus, fluctuant, non-tender, which used to decrease in size on raising the leg and used to blanch on pressure. The parents informed that this swelling was present since birth. Careful scrutiny also revealed that the affected limb was clearly hypertrophied and larger than the unaffected limb.

Fig.1. Right-sided hemarthrosis

An MRI of the right lower limb was suggestive of a diffusely insinuating vascular malformation, haemolymphatic in nature, noted along the antero-medial aspect of the right leg with intra-articular extension and distension of the knee joint with mild joint effusion and evidence of intra-articular hemorrhage due to prior bleeds (Fig. 2). Similar focal lesions were also noted on the dorsum and medial aspect of the foot. The vascular surgeon plans to thrombose the vascular supply of the intra-articular portion of the malformation to prevent the recurrent hemarthrosis which would otherwise eventually destroy the joint.

Fig.2. Intra-articular bleed

Klippel Trenaunay syndrome is a cutaneous vascular malformation that, in combination with bony and soft tissue hypertrophy and venous abnormalities, constitutes the triad of defects of this usually nonheritable disorder [1]. However, interestingly, scattered reports are available in world literature that it may occasionally be inherited [2,3]. Our child had asymmetric limb hypertrophy, vascular malformations as well as a cutaneous vascular malformation on the lower foot. The lower limb is involved in 95% of the cases [4]. While bleeding from the vascular lesions are infrequent complications (hematuria from a vascular malformation of the urinary tract or rectal bleeding from a gut lesion) [4], intra-articular bleeds from such a lesion are extremely rare [5]. Screening of this child revealed no other associated features such as lymphatic obstruction, spina bifida, hypospadias, polydactyly, syndactyly, oligodactyly, orofacial abnormalities, hyperhidrosis, hypertrichosis, paresthesia, or decalcification of bones [4].

1. Cohen M. Klippel-Trenaunay syndrome. Am J Med Genet. 2000;93:171-2.

2. Ceballos-Quintal JM, Pinto-Escalante D, Castillo-Zapata I. A new case of Klippel-Trenaunay-Weber (KTW) syndrome: evidence of autosomal dominant inheritance. Am J Med Genet. 1996;63:426-7.

3. Hofer T, Frank J, Itin PH. Klippel-Trenaunay syndrome in a monozygotic male twin: supportive evidence for the concept of paradominant inheritance. Eur J Dermatol. 2005;15:341-3.

4. Jones K. Smith’s Recognizable Patterns of Human Malformations. 6th ed; Philadelphia, Elsevier Saunders: 2009.p.598-9.