Percutaneous Needle Technique is Comparable to Open Z-plasty Surgery for Unilateral Tendon Achilles Lengthening in Children With Cerebral Palsy

This study aims to compare the outcomes of two surgical techniques for Achilles tendon lengthening in ambulatory children with cerebral palsy (CP): the percutaneous needle technique and the traditional open Z-lengthening technique. The primary objective is to evaluate the effectiveness of these techniques in improving ankle dorsiflexion and gait function one year postoperatively. Secondary objectives include assessing postoperative complications, re-rupture rates, and patient satisfaction. The study is designed as a retrospective, matched-pair cohort study, utilizing data from clinical records, 3D gait analysis (3DGA), and structured telephone interviews.

Study Overview

• Status: Completed
• Conditions: Cerebral Palsy; Gait Analysis in Neurological Disorders; Equinus Foot Deformity in Children With Cerebral Palsy

• Study Type: Observational
• Enrollment (Actual): 20

Contacts and Locations

Study Locations

• Norway
  • Buskerud
    • Drammen, Buskerud, Norway, 3004
      • Vestreviken

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

This retrospective, matched-pair cohort study investigates the outcomes of percutaneous needle technique versus open Z-lengthening for Achilles tendon lengthening in children with spastic cerebral palsy. The study will assess changes in ankle dorsiflexion, gait function, and the incidence of postoperative complications. Data will be gathered from 3D gait analysis reports, clinical records, and structured telephone interviews. The primary outcome is the degree of passive ankle dorsiflexion one year postoperatively. Secondary outcomes include active ankle dorsiflexion, adverse events and re-rupture rates. The results aim to inform clinical decision-making and optimize surgical management for children with CP-related gait impairments.

Description

Inclusion Criteria:

• Ambulatory children with spastic cerebral palsy (unilateral or bilateral).
• Indication for Achilles tendon lengthening confirmed by 3D gait analysis.
• Underwent unilateral either percutaneous needle technique or open Z-lengthening between 2015 and 2022.
• Availability of preoperative and one-year postoperative 3D gait analysis data.
• Informed consent obtained.

Exclusion Criteria:

• Multilevel surgical interventions.
• Previous foot surgeries that alter foot anatomy.
• Non-compliance with rehabilitation protocols or orthotic use.
• Botulinum toxin-A injections in the triceps surae within six months pre- or post-surgery.
• Incomplete or inadequate 3D gait analysis data.
• Lack of informed consent.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Open z-TAL; Patients with CP who has undergone unilateral Tendon Achilles Lengthening by open z-plasty (open z-TAL)
Needle PTAL; Patients with CP who has undergone unilateral Tendon Achilles Lengthening by percutaneous needle technique (needle PTAL)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Passive Ankle Dorsiflexion (Degrees)	Passive Ankle Dorsiflexion (Degrees) measured with the knee flexed.	Measured with the knee extended at one year postoperatively.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Active Ankle Dorsiflexion (Degrees)	Active Ankle Dorsiflexion (Degrees): Measured with the knee extended and flexed.	Measured with the knee extended at one year postoperatively.
Maximum Ankle Dorsiflexion in Stance Phase	Maximum Ankle Dorsiflexion in Stance Phase: Kinematic analysis during 3D gait analysis.	Measured with the knee extended at one year postoperatively.
Propulsive Power in Terminal Stance	Propulsive Power in Terminal Stance: Measured in watts per kilogram using kinetic analysis.	Measured with the knee extended at one year postoperatively.
Postoperative Complications	Postoperative Complications: Incidence of infections, hematoma, and re-ruptures within the first postoperative year.	Measured with the knee extended at one year postoperatively.

Collaborators and Investigators

• Sponsor: Vestre Viken Hospital Trust

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2024
• Primary Completion (Actual): March 1, 2025
• Study Completion (Actual): March 1, 2025

Study Registration Dates

• First Submitted: March 7, 2025
• First Submitted That Met QC Criteria: March 12, 2025
• First Posted (Actual): March 25, 2025

Study Record Updates

• Last Update Posted (Actual): March 30, 2025
• Last Update Submitted That Met QC Criteria: March 28, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Keywords: cerebral palsy; open surgery; tendon Achilles; z-plasty lengthening; needle lengthening technique
• Additional Relevant MeSH Terms: Neurologic Manifestations; Musculoskeletal Diseases; Brain Diseases; Central Nervous System Diseases; Musculoskeletal Abnormalities; Congenital Abnormalities; Brain Damage, Chronic; Lower Extremity Deformities, Congenital; Limb Deformities, Congenital; Cerebral Palsy; Nervous System Diseases; Paralysis; Foot Deformities; Foot Deformities, Congenital
• Other Study ID Numbers: 1000168

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
• product manufactured in and exported from the U.S.: No