Comparison of Dynamic Radiographs in Determining Fusion Level in Adolescent Idiopathic Scoliosis Correction

The purpose of this study is to identify the flexibility radiograph(s) that can most accurately predict the curve behaviour after surgical correction of AIS. With these findings, the investigators hope to give further guidance for the selection of fusion levels and to incorporate different dynamic radiographs into the Lenke Classification, leading to a more universal application that can consistently lead to good surgical and clinical outcome.

Study Overview

• Status: Completed
• Conditions: Adolescent Idiopathic Scoliosis
• Intervention / Treatment: Radiation: Flexibility Radiographs (supine, supine side-bend, FB); Radiation: Flexibility Radiographs (awake traction); Radiation: Flexibility Radiographs (STUGA)

Detailed Description

The Lenke Classification is the most widely-accepted classification for Adolescent Idiopathic Scoliosis (AIS) in the world. Its recommendations for fusion of the minor curves depend on its structurality. It defines a minor curve as structural if there is inflexibility on side-bending more than 25 . However, a recent Delphi survey from a panel of experts in AIS management showed that there was no consensus as to which type of dynamic radiograph was optimal. Up to two thirds of the surgeons did not use side-bending as a routine, and hence they cannot apply the Lenke Classification accurately in clinical practice nor follow its recommendations for fusion.

Furthermore, the current classification does not give specific recommendations regarding the selection of fusion levels and does not take into account the clinical appearance of the patients which impact on treatment. Consequently, there are still controversies regarding the Upper Instrumented Vertebra (UIV) and Lowest Instrumented Vertebra (LIV) selections, and following the recommendations may not allow fusion of the least number of segments nor give best clinical results eg shoulder balance.

• Study Type: Observational
• Enrollment (Actual): 134

Contacts and Locations

Study Locations

• Hong Kong
  • Hong Kong, Hong Kong
    • Duchess of Kent Children's Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 10 years to 18 years (ADULT, CHILD)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

The study will be divided into two phases. In Phase 1, an exploratory pilot study will be performed with up to 3 flexibility films done on the same patient in different spinal centres which are in Hong Kong and Turkey.

Description

Inclusion Criteria:

• Patients diagnosed with AIS who reach the threshold for surgical correction.
• Patients aged 10 to 18 years

Exclusion Criteria:

• Neuromuscular deformity
• Prior fusion or spine surgery
• Spinal tumor diagnosis
• Congenital anomalies

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Hong Kong; Radiation: Flexibility Radiographs (supine, supine side-bend, FB) supine side-bending and fulcrum bending films	Radiation: Flexibility Radiographs (supine, supine side-bend, FB); Supine, supine side-bend, fulcrum bend
Turkey; Radiation: Flexibility Radiographs (supine, supine side-bend, FB) Radiation: Flexibility Radiographs (awake traction) Radiation: Flexibility Radiographs (STUGA) supine side-bending, fulcrum bending films, awake traction and supine traction under GA	Radiation: Flexibility Radiographs (supine, supine side-bend, FB); Supine, supine side-bend, fulcrum bend; Radiation: Flexibility Radiographs (awake traction); awake traction; Radiation: Flexibility Radiographs (STUGA); supine traction under GA

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Investigate the flexibility equivalence of different bending methods, and their predictability of the final outcome	To investigate the flexibility equivalence of different bending methods: supine side-bending, fulcrum bending (FB) and supine Halter traction without GA (awake), and their predictability of the final outcome	6 months to 9 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incorporate these findings into the Lenke Classification of AIS	To incorporate these findings into the Lenke Classification of AIS	6 months to 9 months
Give new recommendations for fusion levels according to the flexibility assessment	To give new recommendations for fusion levels according to the flexibility assessment	6 months to 9 months

Collaborators and Investigators

• Sponsor: The University of Hong Kong
• Collaborators: AO Foundation, AO Spine

Publications and helpful links

General Publications

• Hamzaoglu A, Talu U, Tezer M, Mirzanli C, Domanic U, Goksan SB. Assessment of curve flexibility in adolescent idiopathic scoliosis. Spine (Phila Pa 1976). 2005 Jul 15;30(14):1637-42. doi: 10.1097/01.brs.0000170580.92177.d2.
• Clements DH, Marks M, Newton PO, Betz RR, Lenke L, Shufflebarger H; Harms Study Group. Did the Lenke classification change scoliosis treatment? Spine (Phila Pa 1976). 2011 Jun 15;36(14):1142-5. doi: 10.1097/BRS.0b013e318207e9c4.
• Cheh G, Lenke LG, Lehman RA Jr, Kim YJ, Nunley R, Bridwell KH. The reliability of preoperative supine radiographs to predict the amount of curve flexibility in adolescent idiopathic scoliosis. Spine (Phila Pa 1976). 2007 Nov 15;32(24):2668-72. doi: 10.1097/BRS.0b013e31815a5269.
• Lenke LG, Betz RR, Harms J, Bridwell KH, Clements DH, Lowe TG, Blanke K. Adolescent idiopathic scoliosis: a new classification to determine extent of spinal arthrodesis. J Bone Joint Surg Am. 2001 Aug;83(8):1169-81.
• Chow SC, Shao J, Wang H. Sample Size Calculations in Clinical Research. 2003. Marcel Dekker, New York

Study record dates

Study Major Dates

• Study Start (ACTUAL): May 1, 2016
• Primary Completion (ACTUAL): May 1, 2018
• Study Completion (ACTUAL): December 31, 2018

Study Registration Dates

• First Submitted: September 22, 2017
• First Submitted That Met QC Criteria: September 22, 2017
• First Posted (ACTUAL): September 28, 2017

Study Record Updates

• Last Update Posted (ACTUAL): May 6, 2020
• Last Update Submitted That Met QC Criteria: May 5, 2020
• Last Verified: May 1, 2020

More Information

Terms related to this study

• Keywords: AIS
• Additional Relevant MeSH Terms: Musculoskeletal Diseases; Spinal Diseases; Bone Diseases; Spinal Curvatures; Scoliosis
• Other Study ID Numbers: UW 16-208

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No