Minimal Invasive Scoliosis or Open Surgery

NCT07203586 | Not Yet Recruiting

• 2 other identifiers: MISCOS2025-01956-01
• Study Type: interventional
• Target: 180
• Locations: 1 country
• Sites: 1

Brief Summary

Surgical treatment for idiopathic scoliosis usually involves open surgery from the back (posterior approach). This method corrects the curve and stabilizes the spine using screws and rods, followed by a fusion of the treated segments. The goal is to achieve the best possible alignment of the spine. This type of surgery can be demanding for the body and often requires a longer hospital stay because of tissue damage and pain after the procedure. Traditionally, patients stayed in the hospital for up to a week or more. In recent years, recovery programs such as ERAS (Enhanced Recovery After Surgery) have been introduced. These programs include better pain control, faster mobilization, and improved preparation before surgery. Thanks to these improvements, many patients can now go home one to two days after surgery instead of several days. There has also been a development of minimally invasive surgery (MIS) techniques in spine surgery. These techniques aim to reduce tissue damage and blood loss compared to traditional open surgery. Smaller incisions can lead to less scarring, less pain, and potentially faster recovery. Because scoliosis surgery is complex, it is important to study whether MIS offers the same safety and benefits as traditional surgery. Minimally invasive surgery makes correct screw placement in the curved spine more challenging, as the usual anatomical landmarks are not fully exposed. To ensure accuracy, MIS often uses advanced technologies such as intraoperative 3D imaging or robotic-assisted surgery (RAS). The purpose of this project is to evaluate whether MIS is as safe and effective as traditional open surgery. The study will compare both methods regarding the need for additional surgery, complications, infections, pain, and bone fusion after surgery. It will also examine hospital stay, degree of curve correction, accuracy of screw placement, changes in nerve function during surgery, blood loss, operation time, and patient-reported outcomes. Most existing studies on MIS in scoliosis are based on older or small patient series, and randomized controlled trials are lacking. This research will provide scientific evidence to guide future treatment choices. The aim is to determine whether MIS can deliver the same correction and safety as open surgery while reducing pain, blood loss, and recovery time. If proven effective, these techniques could improve recovery and quality of life for many scoliosis patients.

Conditions

Idiopathic Adolescent Scoliosis; Idiopathic Juvenile Scoliosis

Keywords

Idiopathic scoliosis; Minimally invasive scoliosis surgery; Traditional Open scoliosis surgical correction; Robotic assisted surgery (RAS); Win-odds; non-inferiority randomised controlled trial

Outcome Measures

Primary Outcomes (1)

• The primary outcome measure is the assessment of a composite group of variables by the statistical method of "win odds". The variables are listed in hierarchic order in the "description" below.

  The composite primary endpoint includes: (i) no reoperation within two years (defined as any secondary spinal procedure related to the index operation); (ii) no serious complications, defined as life-threatening events or complications associated with long-term disability; (iii) absence of early surgical site infection, defined as infections occurring within 12 weeks postoperatively; (iv) absence of other inpatient-related infections, such as pneumonia or urinary tract infections; (v) patient-reported pain at two years, measured using the Numeric Rating Scale (NRS) for back and leg pain; (vi) quality of life assessed with the SRS-22r questionnaire, which captures dimensions such as pain, function, self-image, mental health, and satisfaction; and (vii) radiological evidence of successful spinal fusion, defined as bone bridging across the operated spinal levels, either through the facet joints or between vertebral bodies.

  From the inclusion of the first subject up to two years after the operation of the last subject.

Secondary Outcomes (14)

• Inpatient stay

  During the discharge of each subject, assessed up to two weeks after the operation of the last subject.

• Deformity correction rate

  The assessment will take place during the first follow up of each subject (three months postoperatively) and will be assessed up to the first follow-up of the last subject.

• Progression of Cobb angle in the operated levels at 2-years standing x-ray

  At 2-year follow-up for each subject assessed up to the 2-year follow-up of the last subject.

• Progression of secondary curve angles at 2-years standing x-ray

  During the 2-year follow-up for each subject up to the 2-year follow-up of the last subject.

• Perioperative blood loss

  Assessed during the surgery of each subject

Study Arms (2)

Minimally invasive scoliosis surgery group

EXPERIMENTAL

Patients that will be operated by minimally invasive scoliosis surgery

Procedure: Minimally invasive scoliosis surgery

Open scoliosis surgery group

ACTIVE COMPARATOR

Patients that will be operated by traditional scoliosis surgery

Procedure: Traditional open scoliosis surgery group

Interventions

Minimally invasive scoliosis surgery PROCEDURE

Patients undergoing minimally invasive surgery have screws placed using the surgeon's preferred method: 3D navigation, robotic assistance, freehand, or combinations. A long incision of the skin is made without detaching the erector spinae muscles. Each screw is inserted through the musculature, and positioning is verified with intraoperative CT; misplaced screws are corrected. Rods are then shaped, placed, and deformity correction is performed. The surgeon may decorticate some or all facet joints using minimally invasive techniques before closing the wound.

Minimally invasive scoliosis surgery group

Traditional open scoliosis surgery group PROCEDURE

In traditional open scoliosis surgery, the surgeon uses the preferred method for screw placement (3D navigation, robotic assistance, freehand, or combinations). A long incision is made, and the spinal musculature is detached to fully expose the posterior elements. All screws are inserted through this open area, and their positions are verified with intraoperative CT; misplacements are corrected if needed. Rods are shaped, placed, and deformity correction is performed. Decortication of facet joints, spinous processes, and laminae may be performed with a high-speed burr or similar technique. The wound is then closed.

Open scoliosis surgery group

Eligibility Criteria

• Age: 10 Years - 25 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• Written informed consent
• Idiopathic scoliosis
• Age between 10-25 years
• Planed surgery: Posterior correction for scoliosis
• Major curve Cobb angle 75 degrees or less

You may not qualify if:

• Inability to give informed consent
• Other diagnosis of scoliosis than "idiopathic"
• Rigid curves that require posterior or three-column osteotomy/ies
• Previous surgery at the operated levels
• BMI \> 35

Sponsors & Collaborators

• Uppsala University: lead
• University of Oslo: collaborator
• Karolinska University Hopsital: collaborator
• University Hospital, Umeå: collaborator
• Örebro University, Sweden: collaborator
• Skane University Hospital: collaborator
• Sahlgrenska University Hospital: collaborator
• Department of Orthopedics, Uppsala University Hospital: collaborator
• Linkoeping University: collaborator

Study Sites (1)

Akademiska University hospital

Uppsala, Uppsala County, 75185, Sweden

Location

Related Publications (8)

• Dong G, Huang B, Chang YW, Seifu Y, Song J, Hoaglin DC. The win ratio: Impact of censoring and follow-up time and use with nonproportional hazards. Pharm Stat. 2020 May;19(3):168-177. doi: 10.1002/pst.1977. Epub 2019 Oct 31.

  PMID: 31671481 BACKGROUND

• Pocock SJ, Ariti CA, Collier TJ, Wang D. The win ratio: a new approach to the analysis of composite endpoints in clinical trials based on clinical priorities. Eur Heart J. 2012 Jan;33(2):176-82. doi: 10.1093/eurheartj/ehr352. Epub 2011 Sep 6.

  PMID: 21900289 BACKGROUND

• Peng L. The use of the win odds in the design of non-inferiority clinical trials. J Biopharm Stat. 2020 Sep 2;30(5):941-946. doi: 10.1080/10543406.2020.1757690. Epub 2020 May 31.

  PMID: 32475213 BACKGROUND

• Burstrom K, Johannesson M, Diderichsen F. Swedish population health-related quality of life results using the EQ-5D. Qual Life Res. 2001;10(7):621-35. doi: 10.1023/a:1013171831202.

  PMID: 11822795 BACKGROUND

• Fairbank JC, Pynsent PB. The Oswestry Disability Index. Spine (Phila Pa 1976). 2000 Nov 15;25(22):2940-52; discussion 2952. doi: 10.1097/00007632-200011150-00017.

  PMID: 11074683 BACKGROUND

• Matsumoto H, Williams B, Park HY, Yoshimachi JY, Roye BD, Roye DP Jr, Akbarnia BA, Emans J, Skaggs D, Smith JT, Vitale MG. The Final 24-Item Early Onset Scoliosis Questionnaires (EOSQ-24): Validity, Reliability and Responsiveness. J Pediatr Orthop. 2018 Mar;38(3):144-151. doi: 10.1097/BPO.0000000000000799.

  PMID: 27299779 BACKGROUND

• Heintel TM, Dannigkeit S, Fenwick A, Jordan MC, Jansen H, Gilbert F, Meffert R. How safe is minimally invasive pedicle screw placement for treatment of thoracolumbar spine fractures? Eur Spine J. 2017 May;26(5):1515-1524. doi: 10.1007/s00586-016-4908-3. Epub 2016 Dec 8.

  PMID: 27933475 BACKGROUND

• Danielsson AJ, Romberg K. Reliability and validity of the Swedish version of the Scoliosis Research Society-22 (SRS-22r) patient questionnaire for idiopathic scoliosis. Spine (Phila Pa 1976). 2013 Oct 1;38(21):1875-84. doi: 10.1097/BRS.0b013e3182a211c0.

  PMID: 23846501 BACKGROUND

Study Officials

• Nikos Schizas, MD, PhD

  Uppsala University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Nikos Schizas, MD, PhD

CONTACT

0046186170448; nikos.schizas@surgsci.uu.se

Paul Gerdhem, Professor

CONTACT

0046736994409; paul.gerdhem@uu.se

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Masking Details: The study design does not allow blinding of the surgeons and other personnel in the operating theatre. However, the patient and other health-care personnel will be blinded and held up to six months postoperatively. Patient reported outcomes will be assessed without influence of the caregiver.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Patients with idiopathic scoliosis between 10-25 years old scheduled for spinal deformity surgery will be informed about the study at the time of an outpatient visit. Patient eligibility will be established before treatment randomization. Patients will be randomized about one week prior to operation and strictly sequentially to either minimally invasive or open scoliosis surgical correction, as patients are eligible for randomization. If a patient discontinues from the study, the patient number will not be reused, and the patient will not be allowed to re-enter the study.

Study Record Dates

• First Submitted: September 4, 2025
• First Posted: October 2, 2025
• Study Start: October 15, 2025
• Primary Completion (Estimated): December 31, 2028
• Study Completion (Estimated): December 31, 2030
• Last Updated: October 2, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR, ANALYTIC CODE
• Time Frame: Study protocol, statistical analysis and informed consent form is currently available upon request from the study coordinator. The complete clinical study report will be available upon request after the 2-year follow-up of the last subject included. Data registered in Swespine or similar platforms are available upon request.
• Access Criteria: The principal investigator and study coordinators will have access to the data. Other researchers can have access to supporting information upon request.

Locations

SE (1)