TY - JOUR
T1 - Clinical and radiographic results after implant removal in idiopathic scoliosis
AU - Rathjen, Karl
AU - Wood, Megan
AU - McClung, Anna
AU - Vest, Zachary
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2007/9
Y1 - 2007/9
N2 - STUDY DESIGN. Prospective radiographic and clinical analysis of patients with idiopathic scoliosis who had complete implant removal following posterior spinal fusion (PSF) at least 2 years previously. OBJECTIVE. To evaluate the clinical and radiographic effect of implant removal after PSF for idiopathic scoliosis. SUMMARY OF BACKGROUND DATA. Occasionally, implants must be removed following instrumented PSF. Indications for removal include infection and late operative site pain. Previously, it has been thought that there was little morbidity associated with implant removal in the presence of a solid fusion. However, recent studies have reported loss of coronal correction after implant removal in patients who had a PSF for adolescent idiopathic scoliosis. Few long-term studies have assessed the clinical or radiographic results of complete implant removal after PSF. METHODS. We identified 56 patients who had undergone PSF for idiopathic scoliosis and subsequently had complete removal of all instrumentation. None of these patients had a pseudarthrosis at the time of implant removal. After IRB approval, 43 of 56 (77%) patients returned for new standing posteroanterior and lateral spine radiographs and completion of an SRS-22 questionnaire. RESULTS. For the 43 patients who had new radiographs and completed an SRS-22, the time from the original PSF to complete implant removal averaged 2.9 years (range, 7 months to 7.25 years). Twenty-two patients had implants removed because of infection, and 21 patients had implants removed secondary to pain. The average time from implant removal to completion of the most recent radiographs and SRS-22 questionnaire was 9.5 years (range, 3.2-17.9 years). Patients were considered to have had progression of deformity after implant removal if their Cobb angle measurements increased by more than 10°. Two patients had 11° to 20° of coronal plane progression of their main thoracic curve. No patient had more than 10° of coronal plane progression of a lumbar curve. Sagittal curve progression was identified more frequently. Nineteen patients had between an 11° and 20° increase in thoracic kyphosis, and 5 patients had >20° of thoracic kyphosis progression. Patients with >20° of thoracic kyphosis progression after implant removal had greater thoracic kyphosis before surgery and larger main thoracic and lumbar coronal curves at the time of implant removal. Progressive kyphosis did not correlate with: reason for implant removal, length of follow-up, or time from fusion to implant removal. Although total SRS-22 scores correlated inversely with increased thoracic kyphosis, this trend did not reach statistical significance. CONCLUSION. Implant removal after PSF for idiopathic scoliosis may be complicated by progression of deformity. Patients requiring implant removal should be appropriately counseled and monitored.
AB - STUDY DESIGN. Prospective radiographic and clinical analysis of patients with idiopathic scoliosis who had complete implant removal following posterior spinal fusion (PSF) at least 2 years previously. OBJECTIVE. To evaluate the clinical and radiographic effect of implant removal after PSF for idiopathic scoliosis. SUMMARY OF BACKGROUND DATA. Occasionally, implants must be removed following instrumented PSF. Indications for removal include infection and late operative site pain. Previously, it has been thought that there was little morbidity associated with implant removal in the presence of a solid fusion. However, recent studies have reported loss of coronal correction after implant removal in patients who had a PSF for adolescent idiopathic scoliosis. Few long-term studies have assessed the clinical or radiographic results of complete implant removal after PSF. METHODS. We identified 56 patients who had undergone PSF for idiopathic scoliosis and subsequently had complete removal of all instrumentation. None of these patients had a pseudarthrosis at the time of implant removal. After IRB approval, 43 of 56 (77%) patients returned for new standing posteroanterior and lateral spine radiographs and completion of an SRS-22 questionnaire. RESULTS. For the 43 patients who had new radiographs and completed an SRS-22, the time from the original PSF to complete implant removal averaged 2.9 years (range, 7 months to 7.25 years). Twenty-two patients had implants removed because of infection, and 21 patients had implants removed secondary to pain. The average time from implant removal to completion of the most recent radiographs and SRS-22 questionnaire was 9.5 years (range, 3.2-17.9 years). Patients were considered to have had progression of deformity after implant removal if their Cobb angle measurements increased by more than 10°. Two patients had 11° to 20° of coronal plane progression of their main thoracic curve. No patient had more than 10° of coronal plane progression of a lumbar curve. Sagittal curve progression was identified more frequently. Nineteen patients had between an 11° and 20° increase in thoracic kyphosis, and 5 patients had >20° of thoracic kyphosis progression. Patients with >20° of thoracic kyphosis progression after implant removal had greater thoracic kyphosis before surgery and larger main thoracic and lumbar coronal curves at the time of implant removal. Progressive kyphosis did not correlate with: reason for implant removal, length of follow-up, or time from fusion to implant removal. Although total SRS-22 scores correlated inversely with increased thoracic kyphosis, this trend did not reach statistical significance. CONCLUSION. Implant removal after PSF for idiopathic scoliosis may be complicated by progression of deformity. Patients requiring implant removal should be appropriately counseled and monitored.
KW - Idiopathic scoliosis
KW - Implant removal
KW - Kyphosis
KW - Posterior spinal fusion
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U2 - 10.1097/BRS.0b013e31814b88a5
DO - 10.1097/BRS.0b013e31814b88a5
M3 - Article
C2 - 17873809
AN - SCOPUS:34548696842
VL - 32
SP - 2184
EP - 2188
JO - Spine
JF - Spine
SN - 0362-2436
IS - 20
ER -