OFDS includes a wide variety of symptoms which make the diagnosis confusing for the pediatric orthopedic surgeon. The incidence of OFDS type I, the most common type of this syndrome, is 1/50000–1/250000 live birth. Mutation of chromosome X (22.3–22.2) is responsible for this disorder. This gene (Xp22) plays an important role in the development of body organs such as brain, face, limbs, and kidneys [10,11,12]. It encodes a protein localized in the centrosome and basal body of primary cilia. At present, OFDS appears to be a marked subgroup of ciliopathies with heterogeneity [13]. It is important to distinguish type I and II (Mohr syndrome). Type I is associated with cardiac and brain anomalies. Diagnosing Type II is mostly important because of the associated difficulties in the intubation process. This distinction also has important implications in genetic counseling [11]. If OFDS type I is suspected, genetic testing may confirm it. However, the gene associated with the other types is not yet recognized and the diagnosis is mainly clinical [14]. In this case study, we presented a patient with Mohr syndrome who underwent anesthesia for orthopedic surgery. The patient had some typical features of OFDS type II, which can be differentiated from type I and the other types, including high-arch palate, broad nose, hypertelorism, and tongue nodules. One characteristic which can help this differentiation is that the type I presents with milia or small noncancerous cysts on the face and ears [4, 9, 15].
Our patient was a sporadic case with oral, facial, and digital manifestations. The congenital absence of central incisors is a frequent feature of Mohr syndrome, whereas alar hypoplasia, alopecia, and milia are the main characteristics of OFDS type I. Renal involvement in the form of polycystic kidney disease is usually present in type I in contrast to type II. Distinguishing different types of OFDS is also important due to associated involvement of heart, kidney, and central nervous system, especially in type 1 [11, 16, 17]. In our case, these organs were not involved. Craniofacial anomaly and high arch palate in Mohr syndrome can be challenging for anesthesiologists. Difficulty in airway should be anticipated and discussed with the anesthesiologist beforehand. High-arch palate which is associated with some congenital syndromes, is a known cause of difficult laryngoscopy. It may also be difficult to place supraglottic devices such as laryngeal mask airway in these patients, so difficult airway equipment availability is recommended. However, in most of the reported cases, intubation was performed by an anesthesiologist without the use of these devices [18, 19]. Using a Miller blade, the Mallampati grade of our patient was 2 and head extension was normal. Mask ventilation was adequate and we did not encounter any difficulty during intubation.
Mohr syndrome is a very rare type of OFDS. Patients often need several surgical interventions from infancy to adulthood and the surgical team should be prepared for a difficult intubation. Video-assisted laryngoscopy might be safer in these patients.
Polydactyly of the 4 limbs (tetra polydactyly) is very rare, and so is simultaneous preaxial and postaxial polydactyly. We performed an extensive literature search and the only known associated entities were Ellis van Kreveld and OFD syndromes. Hence it is recommended to consider the possibility of OFDS in every child with pre and postaxial tetra polydactyly and then evaluate for associated brain, cardiac and maxillofacial anomalies and be prepared for a difficult intubation in these patients.
