case_images: PMC8131960_01
case_images: The left leg has the typical features of macrodystrophia lipomatosa,
  affecting the whole limb and hemipelvis (a). The patient presented with two
  draining sinuses in an area of indurated skin (b).
case_images: jbji-6-141-g01.jpg
case_images: PMC8131960_01_jbji-6-141-g01.jpg
case_images: Ch1.F1
case_images: A 47-year-old man with gigantism due to static ML of his left leg was referred with a 2-year history of two spontaneously discharging sinuses on the lateral aspect of his left leg (Fig. 1a and b). He was reviewed by a plastic surgeon who concluded that amputation would not be possible as the gigantism extended to above the hip joint and would require a very major reconstruction to close the residual stump (Fig. 1a). The soft tissues on the lateral aspect of his left leg were indurated with two obvious draining sinuses (Fig. 1b).
case_images: Plain X-ray showed the area of new bone formation in the lateral soft tissues (white arrows), separate from the fibula. The ankle joint has
  extensive heterotopic bone formation, deformity and ankylosis.
case_images: jbji-6-141-g02.jpg
case_images: PMC8131960_01_jbji-6-141-g02.jpg
case_images: Ch1.F2
case_images: Plain radiography showed subcutaneous calcification consistent with heterotopic ossification or possible sequestration and infection (Fig. 2).
case_images: MRI revealed the extent of the infection around the heterotopic bone
  (white arrow). The muscles under the HO have undergone significant fatty
  replacement (a). Transverse images (b) show the high signal around the HO
  with oedema in the muscle and subcutaneous tissue (white arrow). There is no
  evidence of infection around the tibia or fibula and the surrounding muscles
  are normal. The fluid around the HO extended to a skin sinus (white
  arrow) (c).
case_images: jbji-6-141-g03.jpg
case_images: PMC8131960_01_jbji-6-141-g03.jpg
case_images: Ch1.F3
case_images: A magnetic resonance imaging (MRI) scan demonstrated fluid around the heterotopic bone, with oedema in the surrounding soft tissues (Fig. 3a, b). This fluid extended to the skin at one of the sinuses (Fig. 3c).
case_images: At operation, the infected HO was found deep to the subcutaneous fat,
  on the surface of the muscle. It separated easily from the tissues and was
  removed.
case_images: jbji-6-141-g04.jpg
case_images: PMC8131960_01_jbji-6-141-g04.jpg
case_images: Ch1.F4
case_images: The infected and dead bone was excised completely and the tissues were closed primarily (Fig. 4).
case_images: At 1 year after surgery, the surgical site is fully healed with no recurrence of infection.
case_images: jbji-6-141-g05.jpg
case_images: PMC8131960_01_jbji-6-141-g05.jpg
case_images: Ch1.F5
case_images: At 1-year follow-up, the wound over the lateral leg was well healed and there were no signs of local recurrence of osteomyelitis (Fig. 5).