Hip Dislocation

Implant devices are important tools - their use is essential across a number of orthopaedic indications, including hip conditions, trauma and limb deformity. Given the vital role fixation devices play in maintaining alignment, promoting healthy bone healing and preventing joint degeneration, it is essential to understand the expected lifetime outcomes of these implants, and evaluate their safety and efficacy. Prospective implant efficacy and safety registries are needed to support this endeavour, especially considering new regulatory requirements from the European Union Medical Devices Regulation (EU MDR) in relation to post-market clinical follow-up (PMCF).

This 10-year follow-up study aims to further investigate long-term migration patterns of the uncemented Delta-TT cup and H-MAX S stem, comparing outcomes between ceramic and polyethylene liners. Given the predictive value of early RSA migration patterns at the 2-year mark for identifying implants at risk of aseptic loosening, we hypothesize that the Delta-TT cup will demonstrate good stability at the 10-year postoperative mark. Besides, it is hypothesized that migration of Delta TT-cups is comparable between ceramic and polyethylene liners. The primary objective of this study is to measure the long-term stability of the Delta TT cup, combined with either a ceramic or cross-linked polyethylene liner, by means of RSA at 10-years postoperatively. Secondary objectives are to measure long-term stability of the H-MAX S stem, by means of RSA at 10-year postoperatively. Furthermore the study aims to measure implant survival rates and patient-reported outcomes for both the Delta-TT cup and H-MAX S stem, comparing outcomes between the ceramic and polyethylene group.

In recent literature, the potential of guided growth of the proximal femur to modify hip growth in patients with cerebral palsy has been shown. Using medial hemi-epiphysiodesis of the proximal femur (TMH-PF) morphology of hips at risk of symptomatic (sub)luxation in cerebral palsy (CP) can be changed, aiming to reduce further hip migration and the need for more invasive surgical treatment modalities. Further research is necessary to assess if the results of TMH-PF in combination with adductor tenotomies are significantly better than the results of the current standard of care; adductor tenotomies alone. The investigators objective is to determine whether guided growth of the proximal femur decreases the risk of further hip migration and need for further surgery in cerebral palsy patients.