Comparing human bone screws to metal screws for flatfoot surgery

Medial Displacement Calcaneal Osteotomy and FDL- Transfer - a Prospective Comparative Study Between Metal/Bio-Tenodesis Screw (Arthrex) and the Human, Allogeneic Cortical Bone Screw (Shark Screw®️, Surgebright-GmbH)

Observational Orthopedic Hospital Vienna Speising · NCT05643079

This study is testing if a new human bone screw works as well as a traditional metal screw for treating flatfoot surgery to see if it can help patients recover better without needing to remove the hardware later.

Quick facts

Study typeObservational
Enrollment40 (estimated)
Ages18 Years and up
SexAll
SponsorOrthopedic Hospital Vienna Speising Academic / other
Locations1 site (Vienna)
Trial IDNCT05643079 on ClinicalTrials.gov

What this trial studies

This observational study aims to compare the effectiveness of a human allogeneic cortical bone screw, known as Shark Screw®, with a traditional metal/Bio-Tenodesis screw in treating symptomatic flatfoot deformities through medializing calcaneal osteotomy and flexor digitorum longus (FDL) tendon transfer. The study will assess union rates, time to union, complication rates, and patient-reported outcomes using various activity scores over a follow-up period of two years. The goal is to determine if the human bone screw can provide similar or better outcomes without the need for hardware removal post-surgery.

Who should consider this trial

Good fit: Ideal candidates for this study are adults with symptomatic flatfoot deformities who require surgical intervention and meet specific inclusion criteria.

Not a fit: Patients with a BMI over 40, active infections, or significant comorbidities may not benefit from this study.

Why it matters

Potential benefit: If successful, this approach could reduce the need for additional surgeries and complications associated with hardware removal, leading to improved patient satisfaction and outcomes.

How similar studies have performed: Previous studies using allogeneic bone screws have shown promising results, indicating low complication rates and high satisfaction, suggesting potential success for this approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria

* Indication for the use of a metal/Bio-Tenodesis screw or human bone screw in medializing calcaneus osteotomy with FDL transfer.
* BMI\< 40 kg/m²

Exclusion Criteria:

* Insufficient knowledge of German
* Alcohol and drug abuse
* Pregnant woman or nursing mother
* Foreseeable compliance problems
* Neoplastic diseases, malignant bone tumors, rheumatoid arthritis
* Active osteomyelitis
* History of foot surgery
* Advanced osteoarthritis of the lower ankle joint
* Ulcerations in the skin of the surgical area
* Immunosuppressive medications that cannot be discontinued
* BMI \>40

Where this trial is running

Vienna

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Flat FeetFlexor Tendon RuptureTibialis Posterior DysfunctionDeformity, Foothuman allogeneic cortical bone screwShark Screw®flat foot deformityFDL Transfer
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.