title: Does It Make a Difference to Stop Fusion at L3 Versus L4 in Terms of Disc and Facet Joint Degeneration: An MRI Study With Minimum 5 Years Follow-up.
abstract: To compare the functional outcomes of patients with idiopathic scoliosis who had surgical correction and fusion with all pedicle screw construct down to L3 or L4 and to evaluate whether saving a mobile lumbar motion segment distally would demonstrate any difference in terms of disc degeneration (DD) and facet joint degeneration (FJD) after minimum 5 years follow-up.
  
  
  
  Selection of lowest instrumented vertebra (LIV) is often difficult when lumbar curve was included into the fusion (L3 vs L4). Saving L4 is believed to be beneficial for preserving motion and preventing degeneration of unfused lumbar spine.
  
  
  
  The L3 group included 21 patients (mean age of 21.4) and L4 group included 16 patients (mean age 22.9). Control group included 30 healthy individuals with no spinal deformities (mean age of 23.8). Follow-up lumbar magnetic resonance images (MRIs) were evaluated for each patient in terms of DD and FJD. Clinical evaluation was done by using the Scoliosis Research Society-22r, Oswestry Disability Index, and Numeric Rating Scale.
  
  
  
  Mean follow-up period was 7.4 (5-10) years in the L3 group and 9 (5-17) years in L4 group. Average correction rates for lumbar curve magnitudes were 78% in the L3 group and 79% in the L4 group, with no significant correction loss at the final follow-up. There was no statistical difference for DD in all groups (p > .05). FJD was significantly greater in both L3 and L4 groups compared to the control group (p < .001). Clinical outcome scores were similar among all three groups (p > .05).
  
  
  
  Spinal balance and corrections remained stable, without showing any decompensation over time. This midterm MRI study demonstrated similar disc and facet degeneration rates for L3 and L4 groups. FJD at the upper two levels adjacent to the LIV was significant for both surgically treated groups. Clinical outcome scores were similar for all groups at minimum 5 years follow-up.
authors.affiliation: Istanbul Spine Center at Florence Nightingale Hospital, Abide-i Hurriyet Cad. No:166, Sisli, 34381, Istanbul, Turkey. Electronic address: enercan@yahoo.com.
authors.forename: Meric
authors.initials: M
authors.lastname: Enercan
authors.affiliation: Department of Orthopaedics and Traumatology, Istanbul Bilim University Faculty of Medicine, Abide-i Hurriyet Cad. No:160, Sisli, 34381, Istanbul, Turkey.
authors.forename: Sinan
authors.initials: S
authors.lastname: Kahraman
authors.affiliation: Department of Orthopaedics and Traumatology, Erzurum Ataturk University Faculty of Medicine, Vani Efendi Mah., Yakutiye, 2540, Erzurum, Turkey.
authors.forename: Sinan
authors.initials: S
authors.lastname: Yilar
authors.affiliation: Department of Orthopaedics and Traumatology, Adnan Menderes University Faculty of Medicine, Merkez Kampusu Aytepe Mevkii, 09100 Aydin, Turkey.
authors.forename: Mutlu
authors.initials: M
authors.lastname: Cobanoglu
authors.affiliation: Department of Orthopaedics and Traumatology, Istanbul Bilim University Faculty of Medicine, Abide-i Hurriyet Cad. No:160, Sisli, 34381, Istanbul, Turkey.
authors.forename: Bahadir Huseyin
authors.initials: BH
authors.lastname: Gokcen
authors.affiliation: Istanbul Spine Center at Florence Nightingale Hospital, Abide-i Hurriyet Cad. No:166, Sisli, 34381, Istanbul, Turkey.
authors.forename: Selhan
authors.initials: S
authors.lastname: Karadereler
authors.affiliation: Department of Radiology, Florence Nightingale Hospital, Abide-i Hurriyet Cad. No:166, Sisli, 34381, Istanbul, Turkey.
authors.forename: Ayhan
authors.initials: A
authors.lastname: Mutlu
authors.affiliation: Department of Radiology, Florence Nightingale Hospital, Abide-i Hurriyet Cad. No:166, Sisli, 34381, Istanbul, Turkey.
authors.forename: Levent Onur
authors.initials: LO
authors.lastname: Ulusoy
authors.affiliation: Department of Orthopaedics and Traumatology, Istanbul Bilim University Faculty of Medicine, Abide-i Hurriyet Cad. No:160, Sisli, 34381, Istanbul, Turkey.
authors.forename: Cagatay
authors.initials: C
authors.lastname: Ozturk
authors.affiliation: Department of Orthopaedics and Traumatology, Istanbul Bilim University Faculty of Medicine, Abide-i Hurriyet Cad. No:160, Sisli, 34381, Istanbul, Turkey.
authors.forename: Erden
authors.initials: E
authors.lastname: Erturer
authors.affiliation: Istanbul Spine Center at Florence Nightingale Hospital, Abide-i Hurriyet Cad. No:166, Sisli, 34381, Istanbul, Turkey.
authors.forename: Elif
authors.initials: E
authors.lastname: Gebes
authors.affiliation: Istanbul Spine Center at Florence Nightingale Hospital, Abide-i Hurriyet Cad. No:166, Sisli, 34381, Istanbul, Turkey.
authors.forename: Tunay
authors.initials: T
authors.lastname: Sanli
authors.affiliation: Department of Orthopaedics and Traumatology, Acibadem University Faculty of Medicine, Buyukdere Cad. No:40 Maslak, Sariyer, 34457, Istanbul, Turkey.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Alanay
authors.affiliation: Istanbul Spine Center at Florence Nightingale Hospital, Abide-i Hurriyet Cad. No:166, Sisli, 34381, Istanbul, Turkey.
authors.forename: Azmi
authors.initials: A
authors.lastname: Hamzaoglu
mesh_terms: D000328:Adult; D005500:Follow-Up Studies; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000209:etiology*; D008159:Lumbar Vertebrae; D008279:Magnetic Resonance Imaging; D012600:Scoliosis / Q000601:surgery*; D013123:Spinal Fusion; D055815:Young Adult; D021801:Zygapophyseal Joint
keywords: Adolescent idiopathic scoliosis; Disc degeneration; Facet joint degeneration; L3 versus L4; Lowest instrumented vertebra