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Adjacent Segment Disease 44 Years Following Posterior Spinal Fusion for Congenital Lumbar Kyphosis
Spine Deformity 5 (2017) 435e439 www.spine-deformity.org
Adjacent Segment Disease 44 Years Following Posterior Spinal Fusion for Congenital Lumbar Kyphosis Avionna Baldwin, BS, Addisu Mesfin, MD* Department of Orthopaedic Surgery, University of Rochester Medical Center, Rochester, NY 14642, USA Received 4 September 2016; revised 13 April 2017; accepted 27 April 2017
Abstract Study Design: Case report. Objective: To report the clinical and imaging findings of a patient with lumbar stenosis 44 years after posterior spinal fusion for congenital lumbar kyphosis. Summary of Background Data: To our knowledge, there are no long-term follow-up reports after posterior spine fusion (PSF) for congenital kyphosis. Congenital kyphosis is an uncommon deformity with the potential to progress rapidly and result in deformity and neurologic deficits. Methods: We report the patient’s history, physical examination, imaging findings, and management in addition to providing a literature review. Results: A 54-year-old-male who underwent T8eL3 PSF in 1972 because of congenital kyphosis presented 44 years after surgery with lower back pain, buttock, and bilateral posterior leg pain. On physical examination, no weakness was elicited and magnetic resonance imaging demonstrated L4eL5 lumbar stenosis. The patient was enrolled in physical therapy and responded well to medical/interventional management. Conclusion: To our knowledge, this is the longest follow-up of surgical management of congenital lumbar kyphosis. Posterior fusion only halted the progression of the kyphosis with subsequent developed of adjacent segment disease distal to the fusion. Level of Evidence: Level IV. Ó 2017 Scoliosis Research Society. All rights reserved. Keywords: Congenital kyphosis; Emivertebrae; Adjacent segment disease; Posterior spinal fusion; Spinal deformity
Congenital kyphosis is a rare deformity in which vertebral anomalies impair the longitudinal growth of vertebral elements in the sagittal plane with subsequent development of posterior angulation [1-10]. Surgery is indicated over nonsurgical approaches (ie, bracing) because spinal cord compression and neurologic deficits can occur as the kyphosis progresses [1,2]. The type of vertebral anomaly, size of deformity, and degree of spinal cord compression determine the operative approach [1-10]. We report a 44-year follow-up of congenital kyphosis of L1 managed with posterior spinal fusion (PSF) and subsequent development of adjacent segment disease at the distal part of the fusion.
Author disclosures: none. *Corresponding author. Department of Orthopaedic Surgery, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Box 665, Rochester, NY 14642, USA. Tel.: (585) 275-5196; fax: (585) 756-4726. E-mail address: [email protected] (A. Mesfin).
Case Report A 54-year-old man who underwent PSF for correction of congenital L1 kyphosis 44 years earlier presented to the office for low back pain and leg pain with ambulation. At the age of five months a chest radiograph was performed for an upper respiratory tract infection and incidentally revealed an L1 Type I (failure of anterior vertebral body formation) with a 50-degree kyphosis from T12 through L2. As the patient grew older, a gibbus deformity in his thoracolumbar junction was noted. Given the absence of neurologic symptoms, the patient was managed medically/interventionally while being closely monitored for the progression of kyphosis. In 1972, the patient presented with lower back pain when seated and a 10-degree limitation of lateral bend bilaterally. Radiographs revealed a kyphosis of 71 degrees from T12 to L2 and 14-degree scoliosis from T12 to L5 convex to the right. A myelogram revealed a myelographic block at T12 and L1. Despite the presence of a myelographic block, the patient did not demonstrate any neurologic deficits.
2212-134X/$ - see front matter Ó 2017 Scoliosis Research Society. All rights reserved. http://dx.doi.org/10.1016/j.jspd.2017.04.006
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A. Baldwin and A. Mesfin / Spine Deformity 5 (2017) 435e439
Because of the progression of the kyphosis and the spinal cord compression, the patient underwent T8eL4 PSF with autogenous left iliac bone graft. Postoperatively, the patient was placed in a plaster cast. Ten months postoperatively, radiographs revealed a 10-degree decrease in kyphosis. In 1975, three years postoperation an intact fusion mass, a 54-degree kyphosis from T12 to L2 and a 73-degree lordosis from L2 to S1 were noted. From 2013 to 2016 (44 years postoperation), the patient has been followed for axial back pain symptoms in addition to neurogenic claudication symptoms. He has no motor or sensory deficits. His radiographs demonstrate a 57-degree kyphosis from T12 to L2 (Fig. 1), and computed
tomography demonstrates a solid fusion mass from T8 to L4 (Fig. 2). The patient’s pelvic incidence (PI) was 73 degrees, with a kyphosis of 7 degrees from L1 to L5 and a PI lordosis mismatch of 80 degrees. Sagittal vertebral axis was positive 2.7 cm. Magnetic resonance imaging (MRI) demonstrated cord signal changes in the T12eL1 region because of the L1 hemivertebrae as well adjacent segment disease (L4eL5 stenosis) (Fig. 3). Subsequent MRI of the lumbar spine obtained 31 months later did not demonstrate significant worsening of the stenosis and degenerative at L4eL5 (Fig. 3C). The patient continues to be managed medically/interventionally with physical therapy, nonsteroidal anti-inflammatory drugs, antiepileptics, as well as
Fig. 1. Anteroposterior (AP) and lateral scoliosis radiographs demonstrating the L1 hemivertebrae (arrow) and posterior spinal fusion. A mild scoliosis is noted on the AP view.
A. Baldwin and A. Mesfin / Spine Deformity 5 (2017) 435e439
437
Fig. 2. (A) Sagittal CT image demonstrating the L1 hemivertebrae and posterior spinal fusion mass (arrow). (B) Axial CT demonstrating degenerative changes at the L4eL5 facet due to adjacent segment disease. CT, computed tomography.
Fig. 3. (A) Sagittal T2-weighted MRI demonstrating stenosis and cord signal change at the T12eL1 region as well as stenosis at L4eL5 due to adjacent segment disease. (B) Axial T2-weighted MRI demonstrating stenosis at L4eL5 with ligamentum flavum hypertrophy. (C) Sagittal T2-weighted MRI obtained 31 months following the initial MRIs with no significant changes in the L4eL5 degenerative changes and canal stenosis. MRI, magnetic resonance imaging.
transforaminal injections. On initial presentation in December 2013, his Oswestry Disability Index (ODI) was 50 and was unchanged in April 2016 at age 50 years. Discussion Congenital kyphosis is rare and can arise from a failure of formation (Type I), failure of segmentation (Type II), or a mixed presentation (Type 3) [1]. In a series of 112 patients with congenital spinal deformity, 76 had kyphoscoliosis and 36 had kyphosis [2]. Congenital kyphosis in the
thoracic spine has the potential to cause neurologic compromise as the spinal cord becomes compressed. Management options include early intervention (prior to age five years) with posterior spinal fusion, combined anterior-posterior fusion, or hemivertebrae resection from an all-posteriorebased approach [1-10]. The vertebral deformity can progress rapidly during adolescent growth, with Type III progressing the most rapidly [1,2,7]. McMaster advocated prophylactic posterior arthrodesis in patients under age five years presenting with a Type I malformation. We believe there is wisdom in this
438
A. Baldwin and A. Mesfin / Spine Deformity 5 (2017) 435e439
recommendation and can potentially avoid the pitfalls of extensive anterior-posterior procedures or attempts at all posterior hemivertebrae resections [3]. Type I (failure of anterior vertebral body formation) is the most common type of congenital kyphosis. In a series of 130 patients with congenital kyphosis 86 (66.2%) were classified as Type I [1]. In another series of 65 patients with congenital kyphosis, 46 (70.8%) were classified as Type I [3]. The patient described in this case also had a Type I deformity. In 1972 when our patient’s surgery was performed, leading spine deformity centers were advocating for anterior and posterior fusions for the management of congenital kyphosis [1,11]. However, because of the morbidity of such an approach and the patient’s lack of neurologic signs and symptoms, it was elected to proceed with posterior arthrodesis only. As was the practice during that era, he was placed in a plaster cast and monitored closely. He demonstrated no evidence of pseudarthrosis during his postoperative radiographs and his 44-year follow-up. In McMaster’s series of 65 patients with congenital kyphosis, he had 11 patients under age five years with a Type I deformity and 17 patients older than five years with a Type I deformity who underwent posterior arthrodesis only [3]. These patients also wore a Risser jacket for six to nine months postoperatively similar to the patient in this case. As was performed in our case, McMaster advocated for a fusion spanning the kyphosis in order to stop the progression of the condition. The use of iliac crest and posterior solid arthrodesis obtained in our patient was critical for preventing neurologic injury. Additional contributors to the patient’s symptoms are the mismatch between his pelvic incidence and lumbar lordosis. Ideally this mismatch is 10 degrees or less as opposed to the 80-degree mismatch in our patient. The mismatch in addition to the adjacent segment disease that can develop following lumbar fusion are major components of his symptoms. Adjacent segment disease can occur in 36% of patients following lumbar spine fusion [12]. Currently a pediatric patient with congenital thoracolumbar kyphosis and evidence of cord signal change would most like be managed via a hemivertebrae resection and fusion with pedicle screw instrumentation. Posterioronly approaches are being increasingly reported [13-15]. Wang et al. reported on 24 patients with congenital kyphosis undergoing posterior-only vertebral column resection [13]. They achieved 67-degree correction with four complications, including a nerve root injury and incomplete spinal cord injury. Short-term constructs (five levels) following posterior hemivertebrae resection have been associated with a 19% rate of proximal junctional kyphosis [14]. Posterior-only vertebral column resections are challenging procedures that should be managed by experienced spine deformity surgeons. There are also case reports of paraplegia following attempts to correct congenital kyphosis with posterior-only approaches and is
important for the patient and family to understand the risks involved [16]. In our patient, the successful arthrodesis spanning the kyphotic deformity was critical in halting the progression of his kyphosis. Although he has adjacent segment disease and pelvic incidence-lumbar lordosis mismatch he continues to function with no neurologic changes. However, if the patient had the posterior arthrodesis prior to age five years as advocated by McMaster in his large series of 65 patients [3], the pelvic incidence-lumbar lordosis mismatch may have been significantly less and the patient may not have developed a symptomatic adjacent segment disease. Lastly, with the exception of a 28-year follow-up of an anterior and posterior fusion approach, most of the literature on congenital kyphosis is limited to follow-up of 10 years [1-11]. Conclusion In summary, this is the longest follow-up, to our knowledge, on a patient undergoing posterior spinal fusion for a Type I congenital kyphosis. Forty-four years later, the patient demonstrates no evidence of pseudarthrosis and is symptomatic only from his adjacent segment disease and stenosis.
References [1] Winter RB, Moe JH, Wang JF. Congenital kyphosis. Its natural history and treatment as observed in a study of one hundred and thirty patients. J Bone Joint Surg Am 1973;55:223e56. [2] McMaster MJ, Singh H. Natural history of congenital kyphosis and kyphoscoliosis. A study of one hundred and twelve patients. J Bone Joint Surg 1999;81:1367e83. [3] McMaster MJ, Singh H. The surgical management of congenital kyphosis and kyphoscoliosis. Spine 2001;26:2146e54. [4] Bollini G, Docquier PL, Viehweger E, et al. Thoracolumbar hemivertebrae resection by double approach in a single procedure: long-term follow-up. Spine (Phila Pa 1976) 2006;31:1745e57. [5] Ruf M, Jensen R, Letko L, Harms J. Hemivertebra resection and osteotomies in congenital spine deformity. Spine (Phila Pa 1976) 2009;34:1791e9. [6] Winter RB, Turek-Shay LA. Twenty-eight-year follow-up of anterior and posterior fusion for congenital kyphosis: a case report. Spine 1997;22:2183e7. [7] Winter RB, Moe JH, Lonstein JE. The surgical treatment of congenital kyphosis. A review of 94 patients age 5 years or older, with 2 years or more follow-up 77 patients. Spine (Phila Pa 1976) 1985;10:224e31. [8] Noordeen MH, Garrido E, Tucker SK, Elsebaie HB. The surgical treatment of congenital kyphosis. Spine (Phila Pa 1976) 2009;34: 1808e14. [9] Smith JT, Gollogly S, Dunn HK. Simultaneous anterior-posterior approach through a costotransversectomy for the treatment of congenital kyphosis and acquired kyphoscoliotic deformities. J Bone Joint Surg Am 2005;87:2281e9. [10] Kim YJ, Otsuka NY, Flynn JM, et al. Surgical treatment of congenital kyphosis. Spine (Phila Pa 1976) 2001;26:2251e7. [11] Hodgson AR. Correction of fixed spinal curves: a preliminary communication. J Bone Joint Surg Am 1965;47:1221e7. [12] Ghiselli G, Wang JC, Bhatia NN, et al. Adjacent segment degeneration in the lumbar spine. J Bone Joint Surg Am 2004;86:1497e503.
A. Baldwin and A. Mesfin / Spine Deformity 5 (2017) 435e439 [13] Wang S, Aikenmu K, Zhang J, et al. The aim of this retrospective study is to evaluate the efficacy and safety of posterior-only vertebral column resection (PVCR) for the treatment of angular and isolated congenital kyphosis. Eur Spine J 2015 [Epub ahead of print]. [14] Wang Y, Kawakami N, Tsuji T, et al. Proximal junctional kyphosis following posterior hemivertebra resection and short
439
fusion in children younger than 10 years. Clin Spine Surg 2017;30:E370e6. [15] Aydogan M, Ozturk C, Tezer M, et al. Posterior vertebrectomy in kyphosis, scoliosis and kyphoscoliosis due to hemivertebra. J Pediatr Orthop B 2008;17:33e7. [16] Lamartina C, Berjano P. Paraplegia after posterior only correction of congenital kyphosis. Eur Spine J 2011;20:1582e3.
Adjacent Segment Disease 44 Years Following Posterior Spinal Fusion for Congenital Lumbar Kyphosis Avionna Baldwin, BS, Addisu Mesfin, MD* Department of Orthopaedic Surgery, University of Rochester Medical Center, Rochester, NY 14642, USA Received 4 September 2016; revised 13 April 2017; accepted 27 April 2017
Abstract Study Design: Case report. Objective: To report the clinical and imaging findings of a patient with lumbar stenosis 44 years after posterior spinal fusion for congenital lumbar kyphosis. Summary of Background Data: To our knowledge, there are no long-term follow-up reports after posterior spine fusion (PSF) for congenital kyphosis. Congenital kyphosis is an uncommon deformity with the potential to progress rapidly and result in deformity and neurologic deficits. Methods: We report the patient’s history, physical examination, imaging findings, and management in addition to providing a literature review. Results: A 54-year-old-male who underwent T8eL3 PSF in 1972 because of congenital kyphosis presented 44 years after surgery with lower back pain, buttock, and bilateral posterior leg pain. On physical examination, no weakness was elicited and magnetic resonance imaging demonstrated L4eL5 lumbar stenosis. The patient was enrolled in physical therapy and responded well to medical/interventional management. Conclusion: To our knowledge, this is the longest follow-up of surgical management of congenital lumbar kyphosis. Posterior fusion only halted the progression of the kyphosis with subsequent developed of adjacent segment disease distal to the fusion. Level of Evidence: Level IV. Ó 2017 Scoliosis Research Society. All rights reserved. Keywords: Congenital kyphosis; Emivertebrae; Adjacent segment disease; Posterior spinal fusion; Spinal deformity
Congenital kyphosis is a rare deformity in which vertebral anomalies impair the longitudinal growth of vertebral elements in the sagittal plane with subsequent development of posterior angulation [1-10]. Surgery is indicated over nonsurgical approaches (ie, bracing) because spinal cord compression and neurologic deficits can occur as the kyphosis progresses [1,2]. The type of vertebral anomaly, size of deformity, and degree of spinal cord compression determine the operative approach [1-10]. We report a 44-year follow-up of congenital kyphosis of L1 managed with posterior spinal fusion (PSF) and subsequent development of adjacent segment disease at the distal part of the fusion.
Author disclosures: none. *Corresponding author. Department of Orthopaedic Surgery, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Box 665, Rochester, NY 14642, USA. Tel.: (585) 275-5196; fax: (585) 756-4726. E-mail address: [email protected] (A. Mesfin).
Case Report A 54-year-old man who underwent PSF for correction of congenital L1 kyphosis 44 years earlier presented to the office for low back pain and leg pain with ambulation. At the age of five months a chest radiograph was performed for an upper respiratory tract infection and incidentally revealed an L1 Type I (failure of anterior vertebral body formation) with a 50-degree kyphosis from T12 through L2. As the patient grew older, a gibbus deformity in his thoracolumbar junction was noted. Given the absence of neurologic symptoms, the patient was managed medically/interventionally while being closely monitored for the progression of kyphosis. In 1972, the patient presented with lower back pain when seated and a 10-degree limitation of lateral bend bilaterally. Radiographs revealed a kyphosis of 71 degrees from T12 to L2 and 14-degree scoliosis from T12 to L5 convex to the right. A myelogram revealed a myelographic block at T12 and L1. Despite the presence of a myelographic block, the patient did not demonstrate any neurologic deficits.
2212-134X/$ - see front matter Ó 2017 Scoliosis Research Society. All rights reserved. http://dx.doi.org/10.1016/j.jspd.2017.04.006
436
A. Baldwin and A. Mesfin / Spine Deformity 5 (2017) 435e439
Because of the progression of the kyphosis and the spinal cord compression, the patient underwent T8eL4 PSF with autogenous left iliac bone graft. Postoperatively, the patient was placed in a plaster cast. Ten months postoperatively, radiographs revealed a 10-degree decrease in kyphosis. In 1975, three years postoperation an intact fusion mass, a 54-degree kyphosis from T12 to L2 and a 73-degree lordosis from L2 to S1 were noted. From 2013 to 2016 (44 years postoperation), the patient has been followed for axial back pain symptoms in addition to neurogenic claudication symptoms. He has no motor or sensory deficits. His radiographs demonstrate a 57-degree kyphosis from T12 to L2 (Fig. 1), and computed
tomography demonstrates a solid fusion mass from T8 to L4 (Fig. 2). The patient’s pelvic incidence (PI) was 73 degrees, with a kyphosis of 7 degrees from L1 to L5 and a PI lordosis mismatch of 80 degrees. Sagittal vertebral axis was positive 2.7 cm. Magnetic resonance imaging (MRI) demonstrated cord signal changes in the T12eL1 region because of the L1 hemivertebrae as well adjacent segment disease (L4eL5 stenosis) (Fig. 3). Subsequent MRI of the lumbar spine obtained 31 months later did not demonstrate significant worsening of the stenosis and degenerative at L4eL5 (Fig. 3C). The patient continues to be managed medically/interventionally with physical therapy, nonsteroidal anti-inflammatory drugs, antiepileptics, as well as
Fig. 1. Anteroposterior (AP) and lateral scoliosis radiographs demonstrating the L1 hemivertebrae (arrow) and posterior spinal fusion. A mild scoliosis is noted on the AP view.
A. Baldwin and A. Mesfin / Spine Deformity 5 (2017) 435e439
437
Fig. 2. (A) Sagittal CT image demonstrating the L1 hemivertebrae and posterior spinal fusion mass (arrow). (B) Axial CT demonstrating degenerative changes at the L4eL5 facet due to adjacent segment disease. CT, computed tomography.
Fig. 3. (A) Sagittal T2-weighted MRI demonstrating stenosis and cord signal change at the T12eL1 region as well as stenosis at L4eL5 due to adjacent segment disease. (B) Axial T2-weighted MRI demonstrating stenosis at L4eL5 with ligamentum flavum hypertrophy. (C) Sagittal T2-weighted MRI obtained 31 months following the initial MRIs with no significant changes in the L4eL5 degenerative changes and canal stenosis. MRI, magnetic resonance imaging.
transforaminal injections. On initial presentation in December 2013, his Oswestry Disability Index (ODI) was 50 and was unchanged in April 2016 at age 50 years. Discussion Congenital kyphosis is rare and can arise from a failure of formation (Type I), failure of segmentation (Type II), or a mixed presentation (Type 3) [1]. In a series of 112 patients with congenital spinal deformity, 76 had kyphoscoliosis and 36 had kyphosis [2]. Congenital kyphosis in the
thoracic spine has the potential to cause neurologic compromise as the spinal cord becomes compressed. Management options include early intervention (prior to age five years) with posterior spinal fusion, combined anterior-posterior fusion, or hemivertebrae resection from an all-posteriorebased approach [1-10]. The vertebral deformity can progress rapidly during adolescent growth, with Type III progressing the most rapidly [1,2,7]. McMaster advocated prophylactic posterior arthrodesis in patients under age five years presenting with a Type I malformation. We believe there is wisdom in this
438
A. Baldwin and A. Mesfin / Spine Deformity 5 (2017) 435e439
recommendation and can potentially avoid the pitfalls of extensive anterior-posterior procedures or attempts at all posterior hemivertebrae resections [3]. Type I (failure of anterior vertebral body formation) is the most common type of congenital kyphosis. In a series of 130 patients with congenital kyphosis 86 (66.2%) were classified as Type I [1]. In another series of 65 patients with congenital kyphosis, 46 (70.8%) were classified as Type I [3]. The patient described in this case also had a Type I deformity. In 1972 when our patient’s surgery was performed, leading spine deformity centers were advocating for anterior and posterior fusions for the management of congenital kyphosis [1,11]. However, because of the morbidity of such an approach and the patient’s lack of neurologic signs and symptoms, it was elected to proceed with posterior arthrodesis only. As was the practice during that era, he was placed in a plaster cast and monitored closely. He demonstrated no evidence of pseudarthrosis during his postoperative radiographs and his 44-year follow-up. In McMaster’s series of 65 patients with congenital kyphosis, he had 11 patients under age five years with a Type I deformity and 17 patients older than five years with a Type I deformity who underwent posterior arthrodesis only [3]. These patients also wore a Risser jacket for six to nine months postoperatively similar to the patient in this case. As was performed in our case, McMaster advocated for a fusion spanning the kyphosis in order to stop the progression of the condition. The use of iliac crest and posterior solid arthrodesis obtained in our patient was critical for preventing neurologic injury. Additional contributors to the patient’s symptoms are the mismatch between his pelvic incidence and lumbar lordosis. Ideally this mismatch is 10 degrees or less as opposed to the 80-degree mismatch in our patient. The mismatch in addition to the adjacent segment disease that can develop following lumbar fusion are major components of his symptoms. Adjacent segment disease can occur in 36% of patients following lumbar spine fusion [12]. Currently a pediatric patient with congenital thoracolumbar kyphosis and evidence of cord signal change would most like be managed via a hemivertebrae resection and fusion with pedicle screw instrumentation. Posterioronly approaches are being increasingly reported [13-15]. Wang et al. reported on 24 patients with congenital kyphosis undergoing posterior-only vertebral column resection [13]. They achieved 67-degree correction with four complications, including a nerve root injury and incomplete spinal cord injury. Short-term constructs (five levels) following posterior hemivertebrae resection have been associated with a 19% rate of proximal junctional kyphosis [14]. Posterior-only vertebral column resections are challenging procedures that should be managed by experienced spine deformity surgeons. There are also case reports of paraplegia following attempts to correct congenital kyphosis with posterior-only approaches and is
important for the patient and family to understand the risks involved [16]. In our patient, the successful arthrodesis spanning the kyphotic deformity was critical in halting the progression of his kyphosis. Although he has adjacent segment disease and pelvic incidence-lumbar lordosis mismatch he continues to function with no neurologic changes. However, if the patient had the posterior arthrodesis prior to age five years as advocated by McMaster in his large series of 65 patients [3], the pelvic incidence-lumbar lordosis mismatch may have been significantly less and the patient may not have developed a symptomatic adjacent segment disease. Lastly, with the exception of a 28-year follow-up of an anterior and posterior fusion approach, most of the literature on congenital kyphosis is limited to follow-up of 10 years [1-11]. Conclusion In summary, this is the longest follow-up, to our knowledge, on a patient undergoing posterior spinal fusion for a Type I congenital kyphosis. Forty-four years later, the patient demonstrates no evidence of pseudarthrosis and is symptomatic only from his adjacent segment disease and stenosis.
References [1] Winter RB, Moe JH, Wang JF. Congenital kyphosis. Its natural history and treatment as observed in a study of one hundred and thirty patients. J Bone Joint Surg Am 1973;55:223e56. [2] McMaster MJ, Singh H. Natural history of congenital kyphosis and kyphoscoliosis. A study of one hundred and twelve patients. J Bone Joint Surg 1999;81:1367e83. [3] McMaster MJ, Singh H. The surgical management of congenital kyphosis and kyphoscoliosis. Spine 2001;26:2146e54. [4] Bollini G, Docquier PL, Viehweger E, et al. Thoracolumbar hemivertebrae resection by double approach in a single procedure: long-term follow-up. Spine (Phila Pa 1976) 2006;31:1745e57. [5] Ruf M, Jensen R, Letko L, Harms J. Hemivertebra resection and osteotomies in congenital spine deformity. Spine (Phila Pa 1976) 2009;34:1791e9. [6] Winter RB, Turek-Shay LA. Twenty-eight-year follow-up of anterior and posterior fusion for congenital kyphosis: a case report. Spine 1997;22:2183e7. [7] Winter RB, Moe JH, Lonstein JE. The surgical treatment of congenital kyphosis. A review of 94 patients age 5 years or older, with 2 years or more follow-up 77 patients. Spine (Phila Pa 1976) 1985;10:224e31. [8] Noordeen MH, Garrido E, Tucker SK, Elsebaie HB. The surgical treatment of congenital kyphosis. Spine (Phila Pa 1976) 2009;34: 1808e14. [9] Smith JT, Gollogly S, Dunn HK. Simultaneous anterior-posterior approach through a costotransversectomy for the treatment of congenital kyphosis and acquired kyphoscoliotic deformities. J Bone Joint Surg Am 2005;87:2281e9. [10] Kim YJ, Otsuka NY, Flynn JM, et al. Surgical treatment of congenital kyphosis. Spine (Phila Pa 1976) 2001;26:2251e7. [11] Hodgson AR. Correction of fixed spinal curves: a preliminary communication. J Bone Joint Surg Am 1965;47:1221e7. [12] Ghiselli G, Wang JC, Bhatia NN, et al. Adjacent segment degeneration in the lumbar spine. J Bone Joint Surg Am 2004;86:1497e503.
A. Baldwin and A. Mesfin / Spine Deformity 5 (2017) 435e439 [13] Wang S, Aikenmu K, Zhang J, et al. The aim of this retrospective study is to evaluate the efficacy and safety of posterior-only vertebral column resection (PVCR) for the treatment of angular and isolated congenital kyphosis. Eur Spine J 2015 [Epub ahead of print]. [14] Wang Y, Kawakami N, Tsuji T, et al. Proximal junctional kyphosis following posterior hemivertebra resection and short
439
fusion in children younger than 10 years. Clin Spine Surg 2017;30:E370e6. [15] Aydogan M, Ozturk C, Tezer M, et al. Posterior vertebrectomy in kyphosis, scoliosis and kyphoscoliosis due to hemivertebra. J Pediatr Orthop B 2008;17:33e7. [16] Lamartina C, Berjano P. Paraplegia after posterior only correction of congenital kyphosis. Eur Spine J 2011;20:1582e3.