User:Lukelahood/Scapulothoracic fusion

Lukelahood/Scapulothoracic fusion
Specialty	Orthopaedic
Frequency	Rare

Scapulothoracic fusion, also known as scapulodesis, scapulothoracic arthrodesis, and scapular fusion, is an orthopedic procedure to immobilize the scapula by achieving bony fusion between the scapula and the ribs, most commonly for the treatment of facioscapulohumeral muscular dystrophy (FSHD). Note that this procedure is distinct from the scapulopexy, versions of which can achieve similar results without bony fusion.

Applicable Conditions

FSHD

FSHD, the most common indication for scapulothoracic fusion, is a progressive muscle disease that affects the muscles around the scapula (periscapular muscles), namely the trapezius and serratus anterior. FSHD more often spares the rotator cuff muscles and deltoid muscle.

Serratus anterior muscle or trapezius muscle palsy

Serratus anterior muscle palsy (long thoracic nerve palsy) is the most common cause of scapular winging. Trapezius muscle palsy (spinal accessory nerve palsy) is another cause of scapular winging. First line therapy for both cases is observation or nerve repair. In cases of failed nerve repair, a pectoralis major transfer or Eden-Lange procedure, respectively, is indicated. Finally, scapulothoracic fusion is considered alternative treatment or salvage treatment for failed muscle transfers.

Clavicular insufficiency

Clavicular insufficiency is a condition in which the clavicle is unable serve its anatomical role as a strut during scapular movement, usually a result of trauma or surgery. When it is accompanied with pain, scapular winging emerges, secondary to the clavicular pain. When claviculectomy is unlikely to be beneficial, scapulothoracic fusion has served as a salvage procedure to alleviate severe pain.

Stroke

Stroke causing flail arm with scapular instability has rarely been treated with scapulothoracic fusion.

Contraindications

• Osteogenesis imperfecta
• Respiratory insufficiency
• Inadequate deltoid muscle strength

Technique

1. Skin and muscles of the upper back are incised and retracted until the ribs are exposed.
2. Posterior surfaces of ribs and anterior surfaces of scapula are decorticated.
3. A bone graft, such autologous cancellous iliac crest, is placed between the ribs and the scapula
4. Metal wires, or achilles tendon grafts, are looped around ribs (4 to 5 ribs are used, ranging from rib 2 to rib 7) and through drilled holes in scapula. Washers or metal plates can be used to reinforce the thin scapular border. The scapula is then tightened in place at 15 - 25 degrees of abduction (upward rotation).
5. Soft tissues are reattached

Risks

In general, most of the risks are in the short term, after surgery.

• Pneumothorax
• Nonunion
• Infection

Outcomes

Overall, outcomes are good, even many years after the procedure.

In most cases, shoulder fatigue, shoulder pain, and scapular winging is eliminated. The neck and shoulder contours are also restored. Active shoulder abduction and flexion significantly increases, although passive range of motion decreases (loss of ability to "throw" the arm up 180 degrees overhead). In some cases of FSHD, gains in shoulder abduction and flexion diminishes in the long term as the deltoid muscle undergoes dystrophy.

References

See also: Scapulopexy, Eden-Lange procedure, and Pectoralis Major Transfer