Introduction to Congenital Upper Extremity and Cervical Deformities

The management of congenital deformities of the upper extremity and cervical spine represents one of the most complex domains in pediatric orthopedics. These conditions, arising from embryological failures of formation, differentiation, or segmentation, often present with profound biomechanical alterations and cosmetic concerns. For the practicing orthopedic surgeon, mastering the operative interventions for these anomalies requires an intimate knowledge of aberrant anatomy, a meticulous surgical technique, and a rigorous adherence to evidence-based indications.

This masterclass synthesizes decades of academic literature and surgical evolution, detailing the operative management of Sprengel deformity, congenital muscular torticollis, congenital pseudarthroses, congenital radial head dislocation, and radioulnar synostosis.

Congenital Elevation of the Scapula (Sprengel Deformity)

Sprengel deformity is the most common congenital anomaly of the shoulder girdle, characterized by a failure of the scapula to descend from its embryonic cervical position to its normal thoracic location by the third month of gestation. This results in a hypoplastic, abnormally rotated, and elevated scapula, frequently tethered to the cervical spine by an omovertebral bone or fibrous band.

Biomechanics and Pathoanatomy

The elevated scapula disrupts normal scapulothoracic rhythm. The glenoid is typically oriented inferiorly, severely restricting shoulder abduction and forward elevation. The trapezius, rhomboids, and levator scapulae are often fibrotic or hypoplastic.

Indications for Surgery

Surgical intervention is generally reserved for patients with:
* Cavendish Grade III or IV deformities: Visible elevation of the shoulder mass (>2-5 cm) with significant cosmetic asymmetry.
* Functional Impairment: Shoulder abduction restricted to less than 90 to 110 degrees.
* Optimal Age: Surgery is best performed between 3 and 8 years of age. Surgery in older children carries a significantly higher risk of brachial plexus traction injuries.

Surgical Warning: Attempting maximal inferior translation of the scapula in a child older than 8 years dramatically increases the risk of brachial plexus palsy. Prophylactic clavicular osteotomy may be required to decompress the neurovascular bundle.

Surgical Techniques: The Woodward Procedure

The Woodward procedure is the gold standard, involving the detachment and distal advancement of the paraspinal musculature origins.

Positioning and Approach:
1. The patient is positioned prone on chest rolls. The entire affected forequarter is prepped and draped free to allow intraoperative manipulation of the shoulder.
2. A midline longitudinal incision is made from the spinous process of C4 to T9.

Step-by-Step Execution:
1. Fascial Incision: The deep fascia is incised in the midline over the spinous processes.
2. Muscle Elevation: The origins of the trapezius and rhomboid major and minor are sharply detached from the spinous processes. The muscle flap is reflected laterally to expose the medial border of the scapula.
3. Omovertebral Excision: The omovertebral bone (present in ~30% of cases) or fibrous band is identified connecting the superomedial angle of the scapula to the cervical spine. This must be meticulously excised extra-periosteally to prevent recurrence.
4. Scapular Release: The levator scapulae is sectioned. The supraspinatus portion of the scapula may be partially resected (partial scapulectomy) if it impinges on the cervical spine during relocation.
5. Distal Relocation: The scapula is pushed inferiorly and rotated to orient the glenoid anteriorly and superiorly.
6. Reattachment: While holding the scapula in its corrected position, the aponeurosis of the trapezius and rhomboids is reattached to the spinous processes at a more inferior level.

Postoperative Protocol

The patient is placed in a shoulder immobilizer for 3 to 4 weeks. Passive range of motion (ROM) exercises begin at week 4, progressing to active ROM and periscapular strengthening by week 6.

Congenital Muscular Torticollis (CMT)

Congenital muscular torticollis results from unilateral fibrosis and contracture of the sternocleidomastoid (SCM) muscle. While the exact etiology remains debated (intrauterine compartment syndrome vs. birth trauma), the clinical presentation is classic: the head is tilted toward the affected side and rotated toward the contralateral side.

Indications for Operative Release

Over 90% of CMT cases resolve with aggressive physical therapy and manual stretching if initiated in the first few months of life. Surgical intervention is indicated when:
* Conservative management fails after 6 to 12 months of compliant stretching.
* The patient presents late (older than 1 year) with established contractures.
* There is progressive facial hemihypoplasia (plagiocephaly) or a rotational deficit exceeding 15 degrees.

Surgical Technique: Bipolar Release of the SCM

While unipolar release (distal only) was historically performed, bipolar release (proximal and distal) yields superior long-term outcomes and reduces recurrence rates.

Positioning:
The patient is positioned supine with a sandbag under the shoulders to extend the neck. The head is turned toward the unaffected side.

Distal Release (Sternal and Clavicular Heads):
1. A 3 cm transverse incision is made one fingerbreadth superior to the medial clavicle, following Langer’s lines.
2. The platysma is divided, and the investing fascia is opened.
3. The sternal and clavicular heads of the SCM are isolated on a right-angle clamp.
4. Critical Step: The muscle heads are divided using electrocautery. The surgeon must remain strictly within the muscle sheath to protect the underlying internal jugular vein, carotid artery, and vagus nerve.

Proximal Release (Mastoid Attachment):
1. A small transverse incision is made just below the mastoid process.
2. The proximal attachment of the SCM is identified and carefully divided.
3. Critical Step: The spinal accessory nerve (CN XI) enters the SCM approximately 3-5 cm distal to the mastoid tip. Dissection must remain highly proximal and superficial to avoid devastating denervation of the trapezius.

Clinical Pearl: Following bipolar release, the surgeon must manually rotate and laterally bend the cervical spine intraoperatively to ensure all tight fascial bands (including the deep cervical fascia) are completely released.

Postoperative Protocol

A soft cervical collar is applied. Aggressive physical therapy is initiated within 48 to 72 hours postoperatively to maintain the corrected position and retrain the cervical musculature.

Congenital Pseudarthrosis of the Upper Extremity

Congenital pseudarthrosis in the upper extremity most commonly affects the clavicle or the bones of the forearm (radius and ulna). The etiology and management of these two entities differ drastically.

Congenital Pseudarthrosis of the Clavicle

Almost exclusively occurring on the right side (unless associated with situs inversus), this condition arises from a failure of the two primary ossification centers of the clavicle to fuse.

Indications for Surgery:
Pain, progressive thoracic outlet syndrome, or severe cosmetic deformity. Surgery is typically delayed until the child is 3 to 5 years old to allow the clavicle to reach a size amenable to internal fixation.

Surgical Technique:
1. A transverse incision is made over the pseudarthrosis site.
2. The hypertrophic fibrous tissue is radically excised back to healthy, bleeding bone.
3. The medullary canals of both fragments are opened with a drill.
4. An autologous iliac crest bone graft (ICBG) is interposed.
5. Rigid internal fixation is achieved using a pre-contoured dynamic compression plate (DCP) or a locking reconstruction plate.

Congenital Pseudarthrosis of the Forearm (Radius/Ulna)

Unlike the clavicle, congenital pseudarthrosis of the forearm is highly associated with Neurofibromatosis Type 1 (NF-1). The biology of the pseudarthrosis site is inherently dysplastic, making standard bone grafting highly prone to failure.

Surgical Pitfall: Never attempt simple autogenous bone grafting and plating for an NF-1 associated forearm pseudarthrosis. The non-union rate approaches 100%.

Surgical Technique: Free Vascularized Fibular Graft (FVFG)
The gold standard for forearm pseudarthrosis is radical resection and reconstruction with a microvascular free fibular graft.
1. Resection: The pseudarthrosis and all surrounding dysplastic periosteum (the "hamartoma") are resected en bloc until healthy cortical bone is reached.
2. Harvest: A vascularized fibular graft is harvested, typically based on the peroneal artery.
3. Inlay/Onlay: The fibula is slotted into the radius or ulna.
4. Microvascular Anastomosis: The peroneal vessels are anastomosed to the radial or ulnar vessels.
5. Fixation: K-wires or custom pediatric plates are used to stabilize the construct while the graft incorporates.

Congenital Dislocation of the Radial Head

Congenital dislocation of the radial head is typically posterior or posterolateral and is often bilateral. It is characterized by a dysplastic, convex radial head, a hypoplastic capitellum, and a shortened ulna.

Diagnosis and Indications

Differentiating congenital from traumatic dislocation is paramount. Congenital cases present with bilateral involvement, an absence of trauma history, and radiographic signs of chronic dysplasia (domed radial head, hypoplastic capitellum).

Indications for Surgery:
Asymptomatic congenital dislocations should not be treated surgically. Prophylactic reduction or excision in a painless, functional elbow is contraindicated. Surgery is indicated only for:
* Severe, progressive pain.
* Significant restriction of elbow flexion or forearm rotation that impairs activities of daily living.

Surgical Management

In Children (Skeletally Immature):
Open reduction is notoriously difficult and prone to stiffness or re-dislocation. If attempted, it requires an ulnar lengthening osteotomy (to pull the radius distally) combined with an annular ligament reconstruction (using a triceps or palmaris longus slip).

In Adults (Skeletally Mature):
For the painful, arthritic congenital dislocation in a mature patient, simple radial head excision is the procedure of choice.
1. A Kocher approach is utilized (interval between the anconeus and extensor carpi ulnaris).
2. The radial nerve is protected by pronating the forearm.
3. The radial head and neck are excised proximal to the bicipital tuberosity.
4. Prosthetic replacement is generally not required unless there is concurrent longitudinal radioulnar instability (Essex-Lopresti equivalent).

Congenital Radioulnar Synostosis

Congenital radioulnar synostosis is a failure of longitudinal segmentation of the radius and ulna during the 7th week of gestation. It most commonly occurs at the proximal metaphysis. The forearm is rigidly fixed, typically in a position of severe pronation.

Biomechanics and Indications

While shoulder abduction and wrist hypermobility can compensate for mild pronation deformities, severe pronation (>60 degrees) prevents the patient from cupping their hands, receiving objects, or feeding themselves.

Indications for Surgery:
* Bilateral deformity with pronation >60 degrees.
* Unilateral deformity with pronation >60 degrees causing severe functional limitation.
* Optimal timing is between 4 and 7 years of age.

Surgical Management: Derotational Osteotomy

Attempts to resect the synostosis and interpose fat, muscle, or synthetic materials (to restore active rotation) have historically yielded dismal results due to high recurrence rates and the absence of functional supinator musculature. Therefore, the standard of care is a derotational osteotomy to place the forearm in a functional, static position.

Target Position:
* Unilateral: 10 to 20 degrees of pronation.
* Bilateral: Dominant arm in 10-20 degrees of pronation (for writing/typing); non-dominant arm in neutral to 20 degrees of supination (for feeding/washing).

Surgical Technique:
1. Site of Osteotomy: The osteotomy can be performed directly through the synostosis mass or at the distal radial diaphysis. Distal osteotomies carry a lower risk of neurovascular compromise.
2. Execution: Through a limited approach, the bone is pre-drilled and osteotomized using a microsaw or osteotomes.
3. Derotation: The forearm is slowly and carefully derotated to the desired position.
4. Fixation: The osteotomy is stabilized using crossed K-wires or a low-profile pediatric plate.

Surgical Warning: Acute derotation of a severe deformity (>60 degrees) places immense tension on the soft tissues, particularly the posterior interosseous nerve (PIN) and the anterior interosseous nerve (AIN). Prophylactic fasciotomies may be required, and the surgeon must be prepared to back off the rotation if distal perfusion is compromised.

Postoperative Protocol

The arm is immobilized in a long-arm cast for 6 to 8 weeks until radiographic union is achieved. Pins are removed in the clinic, and the patient is allowed to resume normal activities. Because the forearm remains a single functional bone, physical therapy is not required for ROM, but occupational therapy is vital to help the child adapt to their new, functional forearm position.

Conclusion

The surgical correction of congenital upper extremity and cervical deformities demands a high level of technical precision and a deep respect for aberrant pediatric anatomy. Whether executing a Woodward procedure for Sprengel deformity, navigating the microvascular complexities of a forearm pseudarthrosis, or carefully derotating a radioulnar synostosis, the orthopedic surgeon must balance the desire for anatomical correction with the imperative to preserve neurovascular function. Through rigorous patient selection and adherence to the evidence-based techniques outlined in this masterclass, surgeons can achieve profound, life-altering improvements in both the function and form of the growing child.