PURPOSE: Sagittal balance has recently been the focus of studies aimed at understanding the correction force required for both coronal and sagittal malalignment. However, the correlation between cervical kyphosis and sagittal balance in AIS patients has yet to be thoroughly investigated. This study aimed to clarify the correlation between cervical alignment and spinal balance in patients with adolescent idiopathic scoliosis (AIS). Here, we hypothesized that cervical kyphosis patients can be classified into groups by the apex of thoracic kyphosis. METHODS: This study included 92 AIS patients (84 females, 8 males; mean age, 15.1 years). Patients were divided into the cervical lordosis (CL), cervical sigmoid (CS), or cervical kyphosis (CK) groups and further classified according to the apex of thoracic kyphosis into High (above T3), Middle (T4-T9), and Low (below T10) groups. RESULTS: There were 17 (18.5 %), 22 (23.9 %), and 53 (57.6 %) patients with CL, CS, and CK, respectively. In the CK group, 13 had CK-High, 35 had CK-Middle, and 5 had CK-Low. The C7 sagittal vertical axis (C7SVA) measurements were most backward in CK-High and most forward in CK-Low. The T5-12 kyphosis (TK) measurement was significantly lower in CK-High. CONCLUSIONS: Most AIS patients had kyphotic cervical alignment. Patients with CK can be classified as having CK-High, CK-Middle, or CK-Low according to the apex of thoracic kyphosis. CK-High is due to thoracic hypokyphosis with a backward balanced C7SVA. CK-Middle is well-balanced cervical kyphosis. CK-Low has forward-bent global kyphosis of the cervicothoracic spine that positioned the C7SVA forward.
PURPOSE: Sagittal balance has recently been the focus of studies aimed at understanding the correction force required for both coronal and sagittal malalignment. However, the correlation between cervical kyphosis and sagittal balance in AISpatients has yet to be thoroughly investigated. This study aimed to clarify the correlation between cervical alignment and spinal balance in patients with adolescent idiopathic scoliosis (AIS). Here, we hypothesized that cervical kyphosispatients can be classified into groups by the apex of thoracic kyphosis. METHODS: This study included 92 AISpatients (84 females, 8 males; mean age, 15.1 years). Patients were divided into the cervical lordosis (CL), cervical sigmoid (CS), or cervical kyphosis (CK) groups and further classified according to the apex of thoracic kyphosis into High (above T3), Middle (T4-T9), and Low (below T10) groups. RESULTS: There were 17 (18.5 %), 22 (23.9 %), and 53 (57.6 %) patients with CL, CS, and CK, respectively. In the CK group, 13 had CK-High, 35 had CK-Middle, and 5 had CK-Low. The C7 sagittal vertical axis (C7SVA) measurements were most backward in CK-High and most forward in CK-Low. The T5-12 kyphosis (TK) measurement was significantly lower in CK-High. CONCLUSIONS: Most AISpatients had kyphotic cervical alignment. Patients with CK can be classified as having CK-High, CK-Middle, or CK-Low according to the apex of thoracic kyphosis. CK-High is due to thoracic hypokyphosis with a backward balanced C7SVA. CK-Middle is well-balanced cervical kyphosis. CK-Low has forward-bent global kyphosis of the cervicothoracic spine that positioned the C7SVA forward.
Authors: Jason E Lowenstein; Hiroko Matsumoto; Michael G Vitale; Mark Weidenbaum; Jaime A Gomez; Francis Young-In Lee; Joshua E Hyman; David P Roye Journal: Spine (Phila Pa 1976) Date: 2007-02-15 Impact factor: 3.468
Authors: D E Harrison; D D Harrison; R Cailliet; S J Troyanovich; T J Janik; B Holland Journal: Spine (Phila Pa 1976) Date: 2000-08-15 Impact factor: 3.468
Authors: Justin K Scheer; Jessica A Tang; Justin S Smith; Frank L Acosta; Themistocles S Protopsaltis; Benjamin Blondel; Shay Bess; Christopher I Shaffrey; Vedat Deviren; Virginie Lafage; Frank Schwab; Christopher P Ames Journal: J Neurosurg Spine Date: 2013-06-14
Authors: Frank J Schwab; Benjamin Blondel; Shay Bess; Richard Hostin; Christopher I Shaffrey; Justin S Smith; Oheneba Boachie-Adjei; Douglas C Burton; Behrooz A Akbarnia; Gregory M Mundis; Christopher P Ames; Khaled Kebaish; Robert A Hart; Jean-Pierre Farcy; Virginie Lafage Journal: Spine (Phila Pa 1976) Date: 2013-06-01 Impact factor: 3.468