ABSTRACT
Objective@#To evaluate the effect of three-dimensional Z-shaped osteotomy with cranium distraction osteogenesis for unilateral lambdoid synostosis.@*Methods@#Imaging the skull as a cuboid, we designed the affected lambdoid suture as the middle line of letter Z, the osteotomy line paralleling to the sagittal suture or extending downward posterior cranial fossa as the two horizontal lines of Z to obtain the three-dimensional Z-shaped osteotomy lines. Two or three distraction devices were installed after removing the cranial bone at the premature fused suture with a width of 2.0-2.5 cm. Since the 5th day after operation, distraction was performed at the rate of 0.6 mm each day, twice a day, until the distraction distance reached 2.0-4.5 cm. Finally, we removed the distractors after fixation for three months.@*Results@#Eleven cases of unilateral lambdoid synostosis were treated successfully. No infection or bleeding happened except for one case with distractor entrance scalp infection. No complications, including the fixed screws displacement, penetrating the cranium and the dura mater or distraction devices retracting, occurred. During a mean follow-up period of 24 months (5 to 36 months), all patients were satisfied with the cosmetic and functional result.@*Conclusions@#Three-dimensional Z-shaped osteotomy with cranium distraction osteogenesis can not only extend upward to raise the cranial height, but also lengthen backward to singularize the occipital carina, forming a well-pleasing occipitalia. Z shape stabilizes the whole plate, making the separated cranial bones not easy to retract. Therefore, using this procedure is effective and mini-invasive, and especially suitable for young infant.
ABSTRACT
Skull is usually available human bone for establishing personal identity. Presence of Inca bone in human skull is one such feature that may be identified on radiological examination and if earlier recorded help in establishing the identity of deceased. Complete division of membranous and cartilaginous part of occipital bone by a transverse suture extending between the two lambdoid sutures at the level of highest nuchal line above the external occipital protuberance, results in rare cranial variation presenting as Inca bone.During medicolegal examination of one male skull at Madhya Pradesh Medicolegal Institute Bhopal, presence of Inca bone was found. The interparietal bone is formed by a part of the squamous occipital bone bounded by two lambdoid sutures on two sides and additional longitudinal suture on both sides between lambdoid suture and external occipital protuberance forming diamond shaped Os Incae Centrale that can also be considered as intra-occipital bone. Such rare findings have significant anthropological and embryological basis. Specific anatomical feature if earlier documented in the clinico-radio-pathological reports of the deceased provides opportunity for establishing the identity.