Medial Displacement Calcaneal Osteotomy and FDL- Transfer - With a Human, Allogeneic Cortical Bone Screw

NCT ID: NCT05643079

Last Updated: 2025-03-20

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

RECRUITING

Total Enrollment

40 participants

Study Classification

OBSERVATIONAL

Study Start Date

2022-02-10

Study Completion Date

2028-02-29

Brief Summary

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The goal of this observational study is to compare the use of a screw made of human bone (Shark-Screw®, Surgebright-GmbH) with the metal/Bio-Tenodesis screw (Arthrex) in the treatment of the symptomatic flatfoot using the medializing calcaneus osteotomy with flexor digitorum longus transfer (FDL) in adult patients. The advantage of the human bone screw is that after surgery no hardware removal is necessary. The screw is transformed from the body to normal bone.

The main questions it aims to answer are:

* Can the human bone screw achieve union rates like the metal/Bio-Tenodesis screw?
* Is the time to union similar between the different screws?
* Is the complication rate similar between the different screws?
* Are the activity scores American Orthopaedic Foot and Ankle Society (AOFAS), Foot and Ankle Outcome Score (FAOS) and Foot Function Index (FFI) after surgery similar in the compared patient groups?

Participants will have

* the surgery
* follow-ups at 6 weeks, 6 months, 1 and 2 years.
* X-rays are performed at each follow up.
* CT-scans are performed after 6 months.
* activity scores are collected at the follow up after 6 months, 1 year and 2 years.

Detailed Description

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Symptomatic flatfoot deformity in adults often occurs as a result of dysfunction of the Tibialis posterior tendon (TPTD), with a prevalence of 3.3%. Structured non-surgical treatment programs with orthotics and physiotherapy can achieve a high level of long-term subjective and functional satisfaction, with surgery being avoided in 70-89% of cases. Surgical intervention is indicated for progressive or uncontrolled symptoms. Flexible flatfoot deformity, stage II classified by Johnson and Strom, can be treated with a joint-preserving strategy, which usually includes a medializing calcaneal osteotomy, debridement of the tibialis posterior tendon, and transfer of the flexor digitorum longus (FDL) tendon. 87% satisfaction after ten years was observed in both pain relief and foot function and alignment.

Metal screws have been used for decades to treat bone fractures. The removal is the major disadvantage of conventional osteosyntheses and requires a second operation, with all the resulting risks of complications for each patient. The use of the bone screw from allogeneic cortical bone would reduce costs substantially, with a significant reduction in the average complication rate to 0.3%.

The idea of stabilizing fractures using compact bone instead of metal is not new. Obwegeser published the clinical use of 796 screw implants of allogeneic bone and reported that the only complication was the fracture of 6 screws (\<1%) and three screw loosening (\<0,5%).

Since 2016, the human, allogeneic cortical bone screw(Shark Screw®) has been used by two tissue banks, the Austrian Austrian tissue bank Surgebright-GmbH and the German Institute for Cell and Tissue Replacement (DIZG). The Shark Screw® graft was approved by the competent Austrian authority (AGES) in 2016. The bone graft immediately creates a solid, purely bony connection. This leads to bone remodeling, bone incorporation and optimal reparation in the surgical area. Depending on the loads and requirements, the bone connection adapts for the future. The bone grafts undergo a certified sterilization procedure at the DIZG, which was developed in 1985 at the Berlin Charité.

Due to the lack of further systematic investigations to objectively confirm the theoretically given and subjectively experienced product advantages, this observational study is now being conducted.

The aim of the present study is to evaluate the application of the human allogeneic cortical bone screw (Shark Screw®) and the metal/Bio-Tenodesis screw in the surgical treatment (medializing calcaneus osteotomy with FDL transfer) of symptomatic flatfoot and to systematically document corresponding clinical and radiological parameters before and after surgery.

Conditions

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Flat Feet Flexor Tendon Rupture Tibialis Posterior Dysfunction Deformity, Foot

Study Design

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Observational Model Type

CASE_CONTROL

Study Time Perspective

PROSPECTIVE

Study Groups

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metal/Bio-Tenodesis group

medializing calcaneal osteotomy, debridement of the tibialis posterior tendon, and/or transfer of the flexor digitorum longus (FDL) tendon with the following screws:

Metal-/Bio-Tenodesis screw (Arthrex, Naples, Florida, USA)

Metal-Screw:

ø 6,7 mm length: 40-60 mm

Bio-Tenodesis screw:

ø 4,00 mm, length: 10 mm ø 4,75 mm, length: 15 mm ø 5,50 mm, length: 15 mm

medializing calcaneal osteotomy and/or transfer of the flexor digitorum longus tendon (FDL) with metal/Bio-Tenodesis screws

Intervention Type PROCEDURE

The calcaneus osteotomy is performed dorsal proximal to plantar distal with caution of the peroneal tendons and sural nerve. After mobilization the dorsal fragment is displaced medially by\~10mm. Thereafter, a guide wire is placed from plantar-lateral into the ventral portion of the calcaneus under fluoroscopic control. After stab incision and length measurement, the osteotomy is fixed with a Metal/Bio-Tenodesis screw(MBS). The lateral projection of the edge is straightened. Opening of the tendon sheath of the FDL muscle and dissection distally to Henry's node. Settling of the tendon and arming with a "shuttle suture". Tendon diameter measurement. Place a guide wire at os naviculare directed from plantar to dorsal in 20°proximal guidance. Pull through the FDL tendon from plantar to dorsal and fixation with an MBS in 20°of pointed foot position and inversion with appropriate desired tension. The tendon is then sutured to the stump of the tibialis posterior tendon, retinaculum sutures.

human, allogeneic cortical bone screw (Shark Screw®)

medializing calcaneal osteotomy, debridement of the tibialis posterior tendon, and/or transfer of the flexor digitorum longus (FDL) tendon with the following screws:

Shark Screw® (Surgebright-GmbH, 4040 Lichtenberg, Austria)

Versions used:

Shark Screw® diver ø: 5,0 mm, length: 35 mm Shark Screw® diver ø: 5,0 mm, length: 45 mm Shark Screw® tendon ø: 5,0 mm, length: 15 mm

medializing calcaneal osteotomy and/or transfer of the flexor digitorum longus tendon (FDL) with Shark Screws®

Intervention Type PROCEDURE

The calcaneus osteotomy is performed dorsal proximal to plantar distal with caution of the peroneal tendons and sural nerve. After mobilization the dorsal fragment is displaced medially by approx.10mm. Thereafter, a guide wire is placed from plantar-lateral into the ventral portion of the calcaneus under fluoroscopic control. After stab incision and length measurement, the osteotomy is fixed with a Shark Screw®. The lateral projection of the edge is straightened. Opening of the tendon sheath of the FDL muscle and dissection distally to Henry's node. Settling of the tendon and arming with a "shuttle suture". Tendon diameter measurement. Place a guide wire at os naviculare directed from plantar to dorsal in 20°proximal guidance. Pull through the FDL tendon from plantar to dorsal and fixation with the Shark Screw® in 20°of pointed foot position and inversion with appropriate desired tension. The tendon is then sutured to the stump of the tibialis posterior tendon, retinaculum sutures.

Interventions

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medializing calcaneal osteotomy and/or transfer of the flexor digitorum longus tendon (FDL) with metal/Bio-Tenodesis screws

The calcaneus osteotomy is performed dorsal proximal to plantar distal with caution of the peroneal tendons and sural nerve. After mobilization the dorsal fragment is displaced medially by\~10mm. Thereafter, a guide wire is placed from plantar-lateral into the ventral portion of the calcaneus under fluoroscopic control. After stab incision and length measurement, the osteotomy is fixed with a Metal/Bio-Tenodesis screw(MBS). The lateral projection of the edge is straightened. Opening of the tendon sheath of the FDL muscle and dissection distally to Henry's node. Settling of the tendon and arming with a "shuttle suture". Tendon diameter measurement. Place a guide wire at os naviculare directed from plantar to dorsal in 20°proximal guidance. Pull through the FDL tendon from plantar to dorsal and fixation with an MBS in 20°of pointed foot position and inversion with appropriate desired tension. The tendon is then sutured to the stump of the tibialis posterior tendon, retinaculum sutures.

Intervention Type PROCEDURE

medializing calcaneal osteotomy and/or transfer of the flexor digitorum longus tendon (FDL) with Shark Screws®

The calcaneus osteotomy is performed dorsal proximal to plantar distal with caution of the peroneal tendons and sural nerve. After mobilization the dorsal fragment is displaced medially by approx.10mm. Thereafter, a guide wire is placed from plantar-lateral into the ventral portion of the calcaneus under fluoroscopic control. After stab incision and length measurement, the osteotomy is fixed with a Shark Screw®. The lateral projection of the edge is straightened. Opening of the tendon sheath of the FDL muscle and dissection distally to Henry's node. Settling of the tendon and arming with a "shuttle suture". Tendon diameter measurement. Place a guide wire at os naviculare directed from plantar to dorsal in 20°proximal guidance. Pull through the FDL tendon from plantar to dorsal and fixation with the Shark Screw® in 20°of pointed foot position and inversion with appropriate desired tension. The tendon is then sutured to the stump of the tibialis posterior tendon, retinaculum sutures.

Intervention Type PROCEDURE

Other Intervention Names

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Metal/Bio-Tenodesis screw intervention Shark Screw® intervention

Eligibility Criteria

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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
Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

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Orthopedic Hospital Vienna Speising

OTHER

Sponsor Role lead

Responsible Party

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Forian Wenzel-Schwarz

Senior Physician Dr. med.

Responsibility Role PRINCIPAL_INVESTIGATOR

Principal Investigators

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Florian Wenzel-Schwarz, MD

Role: PRINCIPAL_INVESTIGATOR

Abteilung für Kinderorthopädie und Fußchirurgie Orthopädisches Spital Speising, Vienna, Austria

Locations

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Abteilung für Kinderorthopädie und Fußchirurgie Orthopädisches Spital Speising

Vienna, , Austria

Site Status RECRUITING

Countries

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Austria

Central Contacts

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Florian Wenzel-Schwarz, MD

Role: CONTACT

+43180182 ext. 3081

Facility Contacts

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Florian Wenzel-Schwarz, MD

Role: primary

+43180182 ext. 3081

References

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Pastl K, Pastl E, Flory D, Borchert GH, Chraim M. Arthrodesis and Defect Bridging of the Upper Ankle Joint with Allograft Bone Chips and Allograft Cortical Bone Screws (Shark Screw(R)) after Removal of the Salto-Prosthesis in a Multimorbidity Patient: A Case Report. Life (Basel). 2022 Jul 11;12(7):1028. doi: 10.3390/life12071028.

Reference Type BACKGROUND
PMID: 35888116 (View on PubMed)

Pastl K, Schimetta W. The application of an allogeneic bone screw for osteosynthesis in hand and foot surgery: a case series. Arch Orthop Trauma Surg. 2022 Oct;142(10):2567-2575. doi: 10.1007/s00402-021-03880-6. Epub 2021 Apr 8.

Reference Type BACKGROUND
PMID: 33834287 (View on PubMed)

Brcic I, Pastl K, Plank H, Igrec J, Schanda JE, Pastl E, Werner M. Incorporation of an Allogenic Cortical Bone Graft Following Arthrodesis of the First Metatarsophalangeal Joint in a Patient with Hallux Rigidus. Life (Basel). 2021 May 24;11(6):473. doi: 10.3390/life11060473.

Reference Type BACKGROUND
PMID: 34073841 (View on PubMed)

Johnson KA, Strom DE. Tibialis posterior tendon dysfunction. Clin Orthop Relat Res. 1989 Feb;(239):196-206.

Reference Type BACKGROUND
PMID: 2912622 (View on PubMed)

Obwegeser JA. [Absorbable and bioconvertible osteosynthesis materials in maxillofacial surgery]. Mund Kiefer Gesichtschir. 1998 Nov;2(6):288-308. doi: 10.1007/s100060050077. German.

Reference Type BACKGROUND
PMID: 9880999 (View on PubMed)

Hanslik-Schnabel B, Flory D, Borchert GH, Schanda JE. Clinical and Radiologic Outcome of First Metatarsophalangeal Joint Arthrodesis Using a Human Allogeneic Cortical Bone Screw. Foot Ankle Orthop. 2022 Jul 29;7(3):24730114221112944. doi: 10.1177/24730114221112944. eCollection 2022 Jul.

Reference Type BACKGROUND
PMID: 35924004 (View on PubMed)

Amann P, Pastl K, Neunteufel E, Bock P. Clinical and Radiologic Results of a Human Bone Graft Screw in Tarsometatarsal II/+III Arthrodesis. Foot Ankle Int. 2022 Jul;43(7):913-922. doi: 10.1177/10711007221081533. Epub 2022 Apr 2.

Reference Type BACKGROUND
PMID: 35373594 (View on PubMed)

Sailer S, Lechner S, Flossmann A, Wanzel M, Habeler K, Krasny C, Borchert GH. Treatment of scaphoid fractures and pseudarthroses with the human allogeneic cortical bone screw. A multicentric retrospective study. J Orthop Traumatol. 2023 Feb 10;24(1):6. doi: 10.1186/s10195-023-00686-7.

Reference Type BACKGROUND
PMID: 36765020 (View on PubMed)

Krasny C, Radda C, Polke R, Schallmayer D, Borchert GH, Albrecht C. A human, allogeneic cortical bone screw for distal interphalangeal joint (DIP) arthrodesis: a retrospective cohort study with at least 10 months follow-up. Arch Orthop Trauma Surg. 2023 Jul;143(7):4557-4564. doi: 10.1007/s00402-023-04785-2. Epub 2023 Feb 9.

Reference Type BACKGROUND
PMID: 36757467 (View on PubMed)

Other Identifiers

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FDLTransferSharkScrew

Identifier Type: -

Identifier Source: org_study_id

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