Proximal Junctional Kyphosis After Vertical Expandable Prosthetic Titanium Rib Insertion

Area of Science:

• Spinal surgery
• Pediatric orthopedics
• Biomechanical engineering

Background:

• Proximal junctional kyphosis (PJK) is a known complication following posterior spinal instrumentation.
• The incidence and characteristics of PJK after vertical expandable prosthetic titanium rib (VEPTR) insertion are not well-documented.
• VEPTR is used to treat thoracic insufficiency syndrome and other conditions causing spinal deformities in growing children.

Purpose of the Study:

• To investigate the occurrence of clinically significant PJK after VEPTR treatment.
• To identify potential risk factors and outcomes associated with PJK in VEPTR patients.

Main Methods:

• Retrospective review of 68 patients treated with VEPTR between 1999 and 2009.
• Data collected included diagnosis, age, VEPTR anchor location, spinal deformity measurements (scoliosis, T2-T12 kyphosis, PJK), and follow-up details.
• Analysis of PJK development, timing, and need for revision procedures.

Main Results:

• Four patients (6%) developed PJK, with a mean follow-up of 5.7 years.
• PJK occurred within the first year post-VEPTR insertion.
• Patients with preoperative thoracic hyperkyphosis appeared to be at higher risk.
• Revision surgery (to growing rods) improved PJK in the affected patients.

Conclusions:

• PJK is a potential complication following VEPTR insertion.
• Preoperative thoracic hyperkyphosis may indicate an increased risk for PJK.
• PJK can be progressive and may necessitate surgical intervention, with revision to growing rods showing positive outcomes in this series.