Mg Alloy DrillPins in Hammertoe Deformity Correction

Official title

The Use of Magnesium (Mg)-Based Absorbable DrillPins in Hammertoe Deformity Correction: a Feasibility Study

Overview

This is a prospective, single-arm clinical feasibility study evaluating the safe application of a novel lean absorbable magnesium-zinc-calcium alloy (ZX00) drill pin (RemeOs™ DrillPin) for the surgical correction of hammertoe deformities. A total of 20 adult patients will be enrolled. All participants will receive the investigational implant without a comparator or control group. The study focuses on feasibility, safety, and functional outcomes following implantation.

Detailed description

This single-arm, open-label, monocenter clinical investigation is conducted in accordance with ISO 14155 to evaluate the safety and performance of the RemeOs™ DrillPin, an absorbable magnesium-zinc-calcium alloy (ZX00) implant, for internal fixation during hammertoe correction surgery in adult patients.

Eligible participants are adults aged 18 years and older with hammertoe deformity of the lesser toes requiring surgical correction, with or without concomitant hallux valgus surgery. The RemeOs™ DrillPin is designed to provide mechanical stability during osteotomy healing and gradually resorbs over time, potentially eliminating the need for implant removal and reducing infection risk through primary wound closure.

Primary objectives include assessing implantation success-defined as low pain levels (VAS \<3) and good or fair toe alignment according to the AOFAS Lesser Metatarsophalangeal-Interphalangeal Scale (AOFAS-LMIS)-at 12 weeks postoperatively, as well as short-term safety, measured by the incidence of adverse and serious adverse device events (ADEs/SADEs).

Secondary assessments include clinical evaluation of pain, wound healing, DIP joint function, and neurovascular status at 2, 4, 6, and 12 weeks, and at 12 and 36 months. Radiographic assessments will monitor alignment, gas formation, and osteolysis at each follow-up, with CT imaging at 12 and 36 months to evaluate implant resorption and potential local effects.

This feasibility study aims to generate initial clinical data on the use of absorbable magnesium-based implants in forefoot surgery and to assess their potential to maintain deformity correction without the need for implant retrieval.

Interventions

• Device Implant Mg-based RemeOs™ drillpins
  This is a first-in-human clinical feasibility study of a novel absorbable magnesium-zinc-calcium alloy DrillPin (RemeOs™) for internal fixation during surgical correction of hammertoe deformities in adult patients. The implant is investigational, not CE-marked, and represents an alternative to conventional stainless steel or titanium K-wires commonly used in toe correction surgery. The RemeOs™ DrillPin is designed to provide mechanical stability during osteotomy healing and gradually resorbs ov

Primary outcome measures

• Number of participants with pain score <3 on the Visual Analogue Scale (VAS) (criterion of successful implantation) [Time frame: At 12 weeks postoperatively]
• Number of participants with good or fair alignment on the AOFAS Lesser Metatarsophalangeal-Interphalangeal Scale (AOFAS-LMIS) (criterion of successful implantation) [Time frame: At 12 weeks postoperatively]
• Number of participants with at least one adverse device event (ADE) or serious adverse device event (SADE) [Time frame: From surgery to 12 weeks postoperatively]

Secondary outcome measures (2)

• Degree of DrillPin resorption [Time frame: 12 and 36 months postoperatively]
• Number of participants with radiographic evidence of subcutaneous gas formation [Time frame: 12 and 36 months postoperatively]

Eligibility criteria

Inclusion criteria

• Hammertoe deformity of the lesser toes, with or without accompanying surgery of a hallux valgus deformity
• Written informed consent of the participant
• Female and male patients aged 18 years and more
• Subject has been informed of the nature of the study, agrees to participate and signs the approved consent form
• Subject is able and willing to comply with all assessments in the study.
• Female patients in childbearing age perform a pregnancy test prior to inclusion

Exclusion criteria

• Pathological bone lesions (e.g., bone cysts or osteomyelitis)
• Underlying diseases (kidney diseases, diabetes mellitus)
• Chronic alcoholics
• Severe mental illness
• Pregnant or breastfeeding women
• Inability or unwillingness to give informed consent

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

Healthy volunteers: No

Study design

Allocation

N/A

Model

Single group

Masking

Open label

Primary purpose

Treatment

Study locations

Center list to be confirmed — check the primary protocol.

Publications

• Klammer G, Baumann G, Moor BK, Farshad M, Espinosa N. Early complications and recurrence rates after Kirschner wire transfixion in lesser toe surgery: a prospective randomized study. Foot Ankle Int. 2012 Feb;33(2):105-12. doi: 10.3113/FAI.2012.0105. PMID 22381341
• Holweg P, Berger L, Cihova M, Donohue N, Clement B, Schwarze U, Sommer NG, Hohenberger G, van den Beucken JJJP, Seibert F, Leithner A, Loffler JF, Weinberg AM. A lean magnesium-zinc-calcium alloy ZX00 used for bone fracture stabilization in a large growing-animal model. Acta Biomater. 2020 Sep 1;113:646-659. doi: 10.1016/j.actbio.2020.06.013. Epub 2020 Jun 14. PMID 32553919
• Bostman O, Pihlajamaki H. Routine implant removal after fracture surgery: a potentially reducible consumer of hospital resources in trauma units. J Trauma. 1996 Nov;41(5):846-9. doi: 10.1097/00005373-199611000-00013. PMID 8913214

Identifiers

NCT: NCT07121790 · 243-03-CI-01

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗