Trapezius sparing minimally aggressive surgical technique for sprengel deformity: A case report

Abstract

Sprengel deformity is a rare congenital anomaly of the pectoral girdle of unknown incidence. Surgical intervention is indicated in moderate to severe cases having functional and cosmetic impairment. Various surgical corrective procedures have evolved over the past decades, however the extensive magnitude of some of the surgical techniques have sometimes resulted in an unwarranted worse outcome due to associated complications like brachial plexus palsy, scapular winging, sternoclavicular joint prominence, improper scar healing and keloid formation which restrict such procedures to experienced hands at few centres. We report a case of Cavendish grade 3 Sprengel deformity in a five-year-old boy managed with a minimally aggressive modified technique of preserving the trapezius and restricting the surgery to excision of omovertebral bar and supraspinatous part of scapula by a transverse incision overlying the spine of scapula. In Sprengel deformity, the trapezius attached to the elevated scapula is underdeveloped and the technique of retraction instead of detachment of this muscle during surgery, can prevent scar adhesions and improve wound healing. In our patient, satisfactory cosmetic correction and good functional shoulder movements were achieved with minimal intervention.

1. Introduction

In 1891, Sprengel¹ described four cases of congenital elevation of scapula. This rare progressive congenital anomaly of the pectoral girdle may be associated with Klippel Feil syndrome, congenital cervical spine abnormalities and renal anomalies, with a spectrum of mild to severe cosmetic deformity and varying degrees of limitation of shoulder abduction.

1.1. Case

A 5 year old boy presented with elevated right shoulder (around 4 cms) Cavendish² grade 3 and limited shoulder abduction (0–60°) [Fig. 1], without facial asymmetry, torticollis or neurological deficit. Radiographs and 3D CT scan morphometric analysis [Fig. 2] revealed the superomedial scapular angle at the level of the 5th cervical (C) vertebrae. A thick omovertebral bar was present between the scapula and the right neural arch of C5-6. (Rigault³ grade 2). Other anomalies included hypoplasia of the right occipital condyle, odontoid process, and C4 vertebra; along with atlantoaxial instability; fusion of C4-5, C5-6, C6-7; with cervical rib; and hemivertebrae at T1, T9 and L5.

Fig. 1.

Preoperative photographs: A. Proximally located scapula seen from the back; B. Restricted shoulder abduction 0–60°.

Fig. 2.

3D CT morphometry showing omovertebral bar.

1.2. Surgical technique

The patient was operated in a floppy lateral semi-prone position under general anaesthesia with the affected right shoulder and arm kept free for necessary intra operative scapulothoracic movements. A 10 cms transverse skin incision was given over the spine of scapula along the Langer’s line. The underdeveloped trapezius was dissected and separated from the underlying muscles using a gloved finger and subsequently retracted to visualize and detach the levator scapulae and rhomboideus at the medial scapular margin, to expose the scapular attachment of the omovertebral bar, which was osteotomized to detether the fixed scapula. The dethering helped in the extraperiosteal exposure of the rest of the omovertebral bar which was subsequently excised from its attachment at the cervical vertebra. The, now mobile, medial border of the scapula was lifted to expose the anterior scapular surface to detach the proximal part of the subscapularis. The posterior surface of the supraspinatous fossa was exposed to detach the supraspinatus muscle, during which the superficially placed underdeveloped trapezius was easily retracted because of the long skin incision. The supraspinatus part of scapula was excised with a bone cutter stopping short of the suprascapular notch avoiding damage to the suprascapular nerve and artery. There was an improvement of the shoulder abduction intraoperatively, obviating the requirement of release of the long head of triceps brachii and teres minor. The wound was closed in layers over a negative suction drain which was removed on the second post-operative day. The cosmetic correction was satisfactorily improved to Cavendish grade 2 without any scar related or other complications and the functional range of abduction improved to 120° at one year follow up [Fig. 3].

Fig. 3.

Post-operative photographs: A. Well healed scar; B. Improved shoulder abduction 0–120°.

2. Discussion

Surgery in Sprengel deformity aims towards the improvement of the shoulder function and cosmesis with the best results in the age group of 3–8 years.

Morphometric analysis using three-dimensional CT, as suggested by Cho et al., is very useful for better preoperative planning and an enhanced perspective of the pathology to evaluate scapular dysplasia and malpositioning.⁴

The surgical outcome depends on factors including age, functional impairment, and associated comorbidities like torticollis, short neck, severe congenital scoliosis and neurological involvement. Surgical correction should be avoided in patients with a short neck and grade 4 deformity.¹

Over the decades, various surgical procedures and their modifications have evolved for cosmetic correction as well as functional improvement of shoulder abduction. Most of these procedures involve extensive soft tissue dissection including detachment of trapezius for the exposure of underlying muscles and scapula before excision of the supraspinatous part of scapula and omovertebral bar excision.

The soft tissue component of different surgical procedures reported in literature, includes caudal placement of scapula and attachment to a rib by Putti⁵ in 1926; reattachment of the extraperiosteally dissected musculature by Green⁵ in 1957 and Leibovic’s⁶ modification of securing the scapula in a pocket of lattisimus dorsi as well as Bellemans and Lamoureux⁷ omission of serratus anterior dissection to prevent winging. Woodward¹ shifted the trapezius and the rhomboids distally and placed the scapula in a pocket of the trapezius. Ahmad⁵ in 2010 anchored the superomedial scapula to the lower dorsal vertebrae, to correct glenoid vara.

Bony procedures apart from excision of supraspinatous part of scapula and omovertebral bar includes clavicle osteotomy by Woodward⁵ in 1961; morcellation of clavicle by Robinson et al.⁸ in 1967; osteotomy of acromion by Shrock⁵ and vertical scapular osteotomy in 1980 by Williamson and Campbell.¹

However various reported complications including brachial plexus palsy, scapula winging, sternoclavicular joint prominence and improper scar healing and keloid formation are always a challenge to the surgeons.¹

There is a recent trend among surgeons to avoid fixing the scapula distally and restrict the surgery to excision of the superomedial part of scapula and the omovertebral bar as a safe and effective method of treatment. Mears⁹ in 2001 described the release of long head of triceps and teres minor to improve shoulder abduction. In 2006, Zhang et al.⁵ described an inverted L skin incision to detach the trapezius and excise the superomedial part of scapula and the omovertebral bar.

The trapezius is not well developed in Sprengel deformity due to the proximal tethering of the scapula and is reported to be atrophic,⁵ hence it can be easily retracted, though with a longer skin incision. This avoids the detachment of the trapezius for excision of the supraspinatous part of scapula and minimizes chances of scar adhesions thereby improving wound healing, with a satisfactory cosmetic outcome.

Aggressive treatment of type 3 Cavendish deformity is not always necessary and surgical procedure may be restricted to a minimum without caudal fixation of the scapula. Preserving the trapezius minimizes the surgical dissection with better wound healing. Cosmetic improvement by the resection of the prominent supraspinous part of the scapula and improvement of the shoulder abduction by excision of the omovertebral bar is often satisfactory to the patient and the parents. We admit the shortcoming of this being a single case report and recommend further studies with bigger sample size.

Conflicts of interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Funding

None.