Multicenter Trial of Proximal Femoral Guided Growth in Children With CP and Hips at Risk of Dislocation (GGSH-MC)

Official title

Guided Growth in Spastic Hip - Multicenter Study (GGSH-MC)

Overview

The Guided Growth in Spastic Hip Multicenter Study (GGSH-MC) is a prospective, multicenter, randomized controlled trial that aims to evaluate the mid-term outcomes of Proximal Femoral Guided Growth (PFGG) in children with spastic cerebral palsy (CP) and hips at risk of dislocation (HRD). Hip dislocation is a common and severe complication in children with CP, especially those who are non-ambulatory, with a reported risk of 70-90%. The trial includes children aged 3 to 8 years with spastic CP and HRD, defined by a migration percentage (MP) between 30% and 60%. Participants will be cluster-randomized by center into two parallel groups: * Experimental Group: Standard prophylactic treatment for HRD + PFGG * Control Group: Standard prophylactic treatment for HRD only PFGG involves insertion of a fully threaded cannulated screw across the lateral cortex and proximal femoral epiphysis under fluoroscopic guidance, with the aim of modulating growth to improve hip containment. All patients will also receive standard soft tissue surgery (adductor and/or psoas tenotomies), as clinically indicated. Follow-up will include clinical, radiographic, and functional assessments at 3 and 6 weeks, and at 6, 12, 18, and 24 months post-intervention. The study will include a 1-year inclusion period and a 2-year follow-up, concluding in October 2027. Primary outcome measures include radiographic indicators of hip displacement. Secondary outcomes include functional scores, complication rates, and need for further surgery. A total of 42 participants (21 per group) will provide 80% power to detect significant differences at a 0.05 significance level. Analyses will be performed using intention-to-treat principles, with subgroup and multivariate analyses to explore modifying factors.

Detailed description

Cerebral palsy (CP) is the leading cause of severe physical disability in childhood, with a prevalence of 1.6 per 1,000 live births in developed countries. Spastic CP, affecting 75% of patients, often leads to progressive musculoskeletal deformities due to muscle imbalance, particularly around the hip joint. Hip dysplasia is the second most common deformity, and if untreated, can progress to dislocation, especially in non-ambulatory children (GMFCS IV-V), where risk exceeds 70%.

Hip displacement in CP is attributed to spasticity of the adductors and flexors, growth-related deformities such as coxa valga and acetabular dysplasia, and limited weight-bearing. These changes can impair function, sitting tolerance, hygiene, and quality of life. Current strategies emphasize surveillance and early intervention for hips at risk of dislocation (HRD), including soft tissue surgery. However, recurrence remains high, and reconstructive surgery, while effective, is invasive and associated with significant morbidity.

Proximal Femoral Guided Growth (PFGG) is a minimally invasive technique involving medial hemiepiphysiodesis with a cannulated screw to modulate proximal femoral growth and improve containment. Though early outcomes are promising, prospective multicenter evidence is limited.

This study is a prospective, multicenter, randomized controlled trial using cluster randomization by center to compare PFGG + standard treatment versus standard treatment alone. Children aged 3-8 years with spastic CP and HRD (MP 30-60%) will be included. The primary outcome is radiographic containment. Secondary outcomes include functional scores, pain, complications, and reintervention rates. Follow-up spans 24 months.

All surgeries follow a standardized protocol. Postoperative care includes early mobilization, use of hip abduction wedge, and physical therapy. Sample size is calculated for 80% power to detect a difference in dislocation rates, requiring 42 subjects. Data will be collected using standardized CRFs and managed centrally under SEOP oversight. Adverse events will be systematically recorded.

The study has IRB approval and complies with ISO 14155, GDPR, and the Helsinki Declaration. Funding is provided by the 2023 EPOS Research Grant (€10,000). Results will be published regardless of outcome.

Interventions

• Procedure Proximal Femoral Guided Growth.
  Proximal Femoral Guided Growth (PFGG) is performed under general anesthesia with the patient in a supine position on a radiolucent table. The surgical field is prepared from the abdomen to the feet. Anatomical landmarks on the femur and femoral neck are marked to guide the procedure. A smooth guidewire (4.0-7.0 mm) is introduced parallel to the table and advanced to the lateral quarter of the femoral neck. A 1-2 cm incision is made along the lateral femur, allowing access to the vastus lateral
• Procedure Standard prophylactic treatment for Hips at Risk of Dislocation.
  Both groups will receive standard prophylactic treatment for HRD, which consists of soft tissue release procedures based on clinical indication and functional level (GMFCS classification): Adductor Tenotomy - Percutaneous or open technique, depending on contracture severity. Psoas Tenotomy - Intrapelvic approach for GMFCS levels I-III and IV (ambulatory). Lesser trochanter approach for GMFCS levels IV-V (non-ambulatory). Additional tenotomies may be performed as needed, targeting muscles contr

Primary outcome measures

• Migration percentage (MP). Radiological [Time frame: Pre-surgery; 3 weeks; 6, 12, 18, and 24 months post-surgery]
• Pelvic Obliquity (PO). Radiological [Time frame: Pre-surgery; 3 weeks; 6, 12, 18, and 24 months post-surgery.]
• Migration Percentage Adjusted for Pelvic Obliquity (PAMP). Radiological [Time frame: Pre-surgery; 3 weeks; 6, 12, 18, and 24 months post-surgery.]
• Acetabular Index (AI). Radiological [Time frame: Pre-surgery; 3 weeks; 6, 12, 18, and 24 months post-surgery.]
• Center-Edge Angle (CEA). Radiological [Time frame: Pre-surgery; 3 weeks; 6, 12, 18, and 24 months post-surgery.]
• Hilgenreiner Epiphyseal Angle (HEA). Radiological [Time frame: Pre-surgery; 3 weeks; 6, 12, 18, and 24 months post-surgery.]

Secondary outcome measures (12)

• Patient characteristics. Age [Time frame: At time of surgery]
• Patient characteristics. Sex [Time frame: Pre-surgery]
• Patient characteristics. Gross Motor Function Classification System level (GMFCS) [Time frame: Pre-surgery]
• Patient characteristics. Weight [Time frame: Pre-surgery]
• Patient characteristics. Orthopedic comorbidities [Time frame: Pre-surgery]
• Patient characteristics. Respiratory disorders or gastrointestinal issues [Time frame: Pre-surgery]
• Patient characteristics. Medication use [Time frame: Pre-surgery]
• Clinical variables. Pain [Time frame: Immediately after surgery; 3 and 6 weeks; 6, 12, 18, and 24 months post-surgery]
• Clinical variables. Analgesic needs [Time frame: Immediately after surgery; 3 and 6 weeks; 6, 12, 18, and 24 months post-surgery]
• Clinical variables. Hip abduction in flexion [Time frame: Pre-surgery; at 6 weeks, 6 months, 12, 18, and 24 months]
• Clinical variables. Hip abduction in extension [Time frame: Pre-surgery; at 6 weeks, 6 months, 12, 18, and 24 months]
• Clinical variables. Hip flexion contracture >20° [Time frame: Pre-surgery; at 6 weeks, 6 months, 12, 18, and 24 months]

Eligibility criteria

Inclusion criteria

• Patients aged 3 to 8 years.
• Diagnosis of predominantly spastic cerebral palsy (CP).
• Any functional level according to the GMFCS.
• Hips at risk of dislocation (HRD), unilateral or bilateral, defined by a migration percentage (MP) between 30% and 60%.

Exclusion criteria

• Children with predominantly hypotonic or dystonic types of CP.
• Children with neuromuscular conditions other than CP.
• Children with high surgical/anesthetic risk.
• Documented history of reconstructive or palliative hip surgery.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Open label

Primary purpose

Treatment

Study locations

Spain · 16 centers

• H. Materno Inf. Teresa Herrera — A Coruña
• Hospital Universitario Torrecárdenas Almeria — Almería
• H.U. Virgen Macarena Sevilla — Seville
• H.U. Virgen Del Rocio — Seville
• Ihp-Orthopediatica Sevilla — Seville
• H. Universitari Son Espases — Palma
• H. Universitario de Salamanca — Salamanca
• H. Sant Joan de Deu — Barcelona
• … and 8 more centers

Publications

• Kiapekos N, Brostrom E, Hagglund G, Astrand P. Primary surgery to prevent hip dislocation in children with cerebral palsy in Sweden: a minimum 5-year follow-up by the national surveillance program (CPUP). Acta Orthop. 2019 Oct;90(5):495-500. doi: 10.1080/17453674.2019.1627116. Epub 2019 Jun 18. PMID 31210072
• Shore BJ, Yu X, Desai S, Selber P, Wolfe R, Graham HK. Adductor surgery to prevent hip displacement in children with cerebral palsy: the predictive role of the Gross Motor Function Classification System. J Bone Joint Surg Am. 2012 Feb 15;94(4):326-34. doi: 10.2106/JBJS.J.02003. PMID 22336971
• Hwang M, Kuroda MM, Tann B, Gaebler-Spira DJ. Measuring care and comfort in children with cerebral palsy: the care and comfort caregiver questionnaire. PM R. 2011 Oct;3(10):912-9. doi: 10.1016/j.pmrj.2011.05.017. PMID 21852220
• Hagglund G, Goldring M, Hermanson M, Rodby-Bousquet E. Pelvic obliquity and measurement of hip displacement in children with cerebral palsy. Acta Orthop. 2018 Dec;89(6):652-655. doi: 10.1080/17453674.2018.1519104. Epub 2018 Oct 17. PMID 30326758
• Narayanan UG, Fehlings D, Weir S, Knights S, Kiran S, Campbell K. Initial development and validation of the Caregiver Priorities and Child Health Index of Life with Disabilities (CPCHILD). Dev Med Child Neurol. 2006 Oct;48(10):804-12. doi: 10.1017/S0012162206001745. PMID 16978459
• Birkenmaier C, Jorysz G, Jansson V, Heimkes B. Normal development of the hip: a geometrical analysis based on planimetric radiography. J Pediatr Orthop B. 2010 Jan;19(1):1-8. doi: 10.1097/BPB.0b013e32832f5aeb. PMID 19829156
• Foroohar A, McCarthy JJ, Yucha D, Clarke S, Brey J. Head-shaft angle measurement in children with cerebral palsy. J Pediatr Orthop. 2009 Apr-May;29(3):248-50. doi: 10.1097/BPO.0b013e31819bceee. PMID 19305274
• Southwick WO. Osteotomy through the lesser trochanter for slipped capital femoral epiphysis. J Bone Joint Surg Am. 1967 Jul;49(5):807-35. No abstract available. PMID 6029256

Identifiers

NCT: NCT06956729 · P.I.R-0041-24 · PR-PI24-00016

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗