Study design:

Case report.

Introduction:

Instrumented posterior fusion using pedicle screws has been the mainstay of the surgical correction of adolescent idiopathic scoliosis since it was popularised by Roy-Camille in the 1970s. The aim of this case report is to describe the occurrence and salvage of an L1 chance fracture occurring through the lower instrumented vertebra following pedicle screw placement for posterior spinal instrumented fusion in the treatment of adolescent idiopathic scoliosis (AIS).

Case report:

A 15-year-old female patient underwent T2-L1 posterior instrumented fusion for a Lenke 1b deformity. The selection of fusion levels was made based upon standing and bending radiographs which showed a non-structural lumbar curve. Early recovery was uneventful. At 6 months post-operatively, the patient reported new deformity and pain. A chance fracture at L1 was diagnosed and subsequent extension of instrumentation to L3 was carried out. Final post-operative recovery was uneventful and the patient returned to an active lifestyle.

Conclusion:

Several factors can contribute to the occurrence of a fracture through an instrumented pedicle. This case shows that there must be due consideration of the small pedicle at L1 when it is chosen as the LIV.