Plate vs. Screw for Guided Growth in Coronal Knee Deformities

Not Applicable

Not yet recruiting

• Conditions: Genu Varum; Genu Valgum; Epiphysiodesis; Bone Malalignment; Lower Extremity Deformities, Congenital

• Registration Number: NCT06879015
• Lead Sponsor: Assiut University

Brief Summary

The goal of this clinical trial is to compare two surgical techniques, Tension Band Plate (TBP) and Percutaneous Epiphysiodesis by Transphyseal Screw (PETS), in children with coronal angular knee deformities.

The main questions it aims to answer are:

* Which technique provides better correction of coronal knee deformities?

* Are there differences in complication rates or recovery times between TBP and PETS?

Participants will:

* Undergo either TBP or PETS surgery for knee deformity correction.

* Attend follow-up visits for radiographic and clinical evaluations.

Researchers will compare TBP and PETS groups to see if one method leads to better deformity correction and fewer complications.

Detailed Description

Genu varum and genu valgum are common lower limb deformities observed in children and adolescents. These conditions often require guided growth techniques for correction. One widely accepted approach for modulating growth and gradually correcting these deformities is temporary Hemi-epiphysiodesis. The two most commonly used techniques for this purpose are the Tension Band Plate (TBP) e.g. Eight-Plate and Percutaneous Epiphysiodesis using Transphyseal Screws (PETS). While both methods have proven effective, there remains ongoing debate about their relative efficacy, safety, and long-term outcomes.

The TBP technique, introduced as a less invasive method of guided growth, involves placing a non-locking plate and screws across the growth plate on one side allowing controlled correction without permanent damage to the physis.

Studies have demonstrated its effectiveness in treating angular deformities with a lower risk of growth plate closure, but concerns remain regarding implant migration, breakage, and rebound deformity post-removal. Conversely, PETS offers a minimally invasive alternative where transphyseal screws modulate growth without requiring plate fixation. Some studies suggest PETS may provide more rapid correction with fewer complications, while others highlight the potential risk of premature physeal closure, which could lead to limb length discrepancies.

Despite the widespread use of both techniques, there is limited high-quality comparative data to determine the superior method in terms of correction rate, complication profile, and long-term functional outcomes. A randomized controlled study comparing TBP and PETS is essential to establish evidence-based guidelines, optimize patient outcomes, and refine surgical decision-making in the management of genu varum and genu valgum. Our novel introduction of the Bone-Length Adjusted Correction Rate as a new criterion will further enhance the measurement of effectiveness for these interventions.

Study Timeline

• Status Verified: 2025-03
• Study First Submitted: 2025-03-11
• Study First Submitted QC: 2025-03-14
• Last Update Submitted: 2025-03-14
• Study First Posted: 2025-03-17
• Last Update Posted: 2025-03-17
• Study Start: 2025-04-01
• Primary Completion: 2027-04-01
• Study Completion: 2027-06-01

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 60

Inclusion Criteria

1. Children and adolescents beyond the age of physiological varus/valgus correction (i.e., typically ≥4 years for genu varum and ≥7 years for genu valgum) with Mechanical Axis Deviation (MAD) in lower limbs and abnormal joint orientation angles, in the coronal plane either femoral or tibial.
2. Open physis (growth plate) on radiographs and at least one year of growth remaining before age of skeletal maturity (typically ≤14 years in females, ≤16 years in males).

Exclusion Criteria

1. Sick Physis as in Blount's disease stages III-V or any partial or total physeal arrest caused by trauma, inflammation or neoplasia.

2. Uncorrectable systemic disorders affecting bone growth and alignment, including but not limited to:

   i- Severe metabolic disorders (e.g., advanced rickets, hypophosphatasia, mucopolysaccharidoses) ii- Uncontrolled endocrine disorders (e.g., untreated hypothyroidism, growth hormone abnormalities) iii- Severe connective tissue disorders (e.g., osteogenesis imperfecta, advanced Ehlers-Danlos syndrome) iv- Chronic inflammatory or hematologic conditions that impair bone growth (e.g., severe juvenile idiopathic arthritis, advanced sickle cell disease)

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Bone-Length Adjusted Angular Correction Rate (BLAACR)	Measured at 3-month intervals until clinical correction is achieved, up to 12 months	The Bone-Length Adjusted Angular Correction Rate (BLAACR) measures the effectiveness of guided growth correction by normalizing the angular correction rate based on limb growth. This method reduces bias in comparing the Tension Band Plate (TBP) and Percutaneous Epiphysiodesis by Transphyseal Screw (PETS) by accounting for variations in growth rate among participants. The formula is: BLAACR = (Change in Angular Deformity) / (Increase in Bone Length), where: -- Change in Angular Deformity = Initial Angle - Final Angle; * Increase in Bone Length = Initial Bone Length - Final Bone Length

Secondary Outcome Measures

Name	Time	Method
Angular Correction Rate (Degrees/Month)	Measured at 3-month intervals until clinical correction is achieved, up to 12 months	Measures the rate of angular deformity correction over time without adjusting for bone growth. This is calculated as: (Initial Angle - Final Angle) / Total Months of Follow-up.
Complications (Pain, Infection, Hardware Migration/Breakage)	Evaluated at each follow-up visit (3, 6, 9, 12 months)	Assess the frequency and severity of complications related to TBP and PETS, including post-operative pain (measured using a visual analog scale), surgical site infections, implant migration, and hardware failure.

Trial Locations

Locations (1)

Assiut University Hospital; 🇪🇬 Asyut, Egypt