Discussion
Sprengel´s deformity (SD), also called "high scapula”, is a rare disorder but still the most frequent congenital anomaly of the shoulder, consisting of an elevated and adducted scapula and often axial rotation. It is more common in men and is usually left-sided; if bilateral, the left side is more severely affected.
SD is caused by a failure in the embryological migration of the scapula from the fourth or fifth cervical vertebrae to its final posterior thoracic location between the second and eighth ribs. 20-50% of cases are due to the existence of an omovertebral BAR, consisting of fibrous, cartilaginous and/or real bony components, which attaches obliquely the superomedial extreme of the scapula to the spinous processes, transverse processes or laminae of the fourth to the seventh cervical vertebrae [1-5].
Other abnormalities associated with Sprengel´s deformity are Klippel-Feil syndrome (fusion of two or more cervical vertebral segments, present in our patient), spina bifida, syringomyelia, diastematomyelia, congenital kyphoscoliosis, cervical ribs, absent or fused ribs, hypoplasia or atrophy of the regional muscles, dysplasia of the clavicle and humerus, renal anomalies [2, 3, 5, 6].
Clinically there is asymmetry between shoulders and reduced abduction of the affected scapula, sometimes with a short neck and torticollis. Cavendish´s classification sets out four degrees of severity depending on the cosmetic deformity (3, 8, 9); our case was a grade 1, unnoticed until this moment.
Simple chest X-ray shows elevation and rotation of a scapula. Scoliosis must be also ruled out. CT with multiplanar and 3D reconstructions is a valuable diagnostic technique and guides surgical management [1, 4, 7, 8]. Visualization of a scapula in an axial plane of the back of a child, with absent contralateral scapula because they are not situated at the same level, as well as the demonstration of a omovertebral bone in the expected location, confirm the suspected diagnosis [2, 7]. In our case, as in most, the left scapula is dysplastic, with convex medial margin and bending forward the supraspinous portion.
Ultrasound is useful detecting cartilaginous and/or fibrous structures, with the advantage of being quick, noninvasive and widely accessible. MR imaging is also useful but it is not as quick and readily available.
Surgical treatment is reserved for severe deformities or dysfunctions between 3 and 8 years of age [2, 5, 8, 9]. Conservative treatment consists of exercises to maintain mobility and strengthen muscles.
