Bio-Integrative Versus Metallic Screws for Calcaneus Osteotomies

Study Overview
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Brief Summary
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The use of bio-integrative implants in orthopedic surgery is growing exponentially. As many biomechanical and histological studies were able to sustain its structural and biological properties, few clinical studies are available to support its advantages, such as good osteosynthesis, lower rates of removal, and diminished implant-related artifact in imaging studies. This information is vital to providers when choosing the proper material and planning postoperative treatment. This trial intends to test the capacity of the bioabsorbable screws in reaching the same clinical and radiographical outcomes of the current metallic screws.

Detailed Description
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A minimum of 44 patients undergoing Medial or Lateral Displacement Calcaneal Osteotomy (MDCO) will be randomized in two parallel groups for surgery, considering applied the implant. One group will be operated using two 4.0mm cannulated bio-integrative (absorbable) screws, and the other group using two 4.0mm cannulated metallic screws. Patients will be blinded evaluated for a mean follow-up of twelve weeks in terms of bone healing, complications, and implant-related artifact using weight-bearing computed tomography (WBCT).

Official Title
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Bio-Integrative Versus Metallic Screws for Calcaneus Osteotomies: A Non- Inferiority Randomized Clinical Trial

Conditions
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Flatfoot, Bone Resorption, Cavus Deformity, Osteolysis, Complication

Intervention / Treatment
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* Procedure: Calcaneus Osteotomy (Metallic)
* Procedure: Calcaneus Osteotomy (Bio-integrative)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Individuals must be older than 18 and younger than 75 years of age, both genders; Participants must be experiencing symptoms related to their baseline condition for at least six months before the surgery; Clinical diagnosis of hindfoot malignment, defined as the presence of a clinical hindfoot angle above 10 degrees of valgus or any degree of varus; Surgical planning, including a calcaneus displacement osteotomy through a traditional oblique cut. Exclusion Criteria: Previous surgery involving the affected calcaneus; History or documented evidence of autoimmune or peripheral vascular diseases; History or documented evidence of peripheral neuropathy (nervous compression syndrome, tarsal tunnel syndrome) or systemic inflammatory disease a (rheumatoid arthritis, spondylitis, Reiter Syndrome, etc.); Any condition that represents a contraindication of the proposed therapies; Impossibility or incapacity to sign the informed Consent Form; Presence of infectious process (superficial on the skin and cellular tissue, or deep in the bone) in the region to be treated. Osteotomies requiring resection of wedges (Dweyer, triple Dweyer, etc.); Osteotomies planned to occur in a non-traditional cut (Malerba, Scarf, etc.).

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Randomized, investigator-blinded, in parallel groups, two-arms, single-center, non-inferiority, clinical trial.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Bio-integrative<br>Traditional oblique calcaneus osteotomy through a lateral approach. After a 10mm displacement, the osteotomy will be fixed with two 4.0mm bio-integrative cannulated screws. | Procedure: Calcaneus Osteotomy (Bio-integrative)<br>* Calcaneus Displacement Osteotomy using two bio-integrative screws<br>|
| Active Comparator: Metallic<br>Traditional oblique calcaneus osteotomy through a lateral approach. After a 10mm displacement, the osteotomy will be fixed with two 4.0mm metallic cannulated screws. | Procedure: Calcaneus Osteotomy (Metallic)<br>* Calcaneus Displacement Osteotomy using two metallic screws<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Bone healing | - Amount of bone bridging crossing the osteotomy site: Determined by the percentage of bone trabeculae crossing the osteotomy site on every tomography cut (amount of the cut in millimeters that shows bone spanning the two fragments divided by the total amount of osteotomy's surface on the cut). - Weight-bearing computed tomography (WBCT) acquisitions will be used to determine this percentage. | 6 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Complications | - Percentage of minor and major complications: Dehiscence: inability to heal the soft tissue coverage until the end of the 4th post-operative week. Peripherical nerve damage: hypoesthesia or paresthesia not solved until the 6th week after the surgery. Infection: clinical signs of site infection or pus drainage at the wound that required antibiotics. | 6 weeks | 
| Implant-related artifact | - Quantity of Hounsfield units around the implants Measured on WBCT acquisitions. | 6 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Bone Healing, Osteotomy, Calcaneus, Bio-integrative, Metallic, Screws