Hallux Valgus Correction Using the Metal Screw or the Human Allogeneic Cortical Bone Screw (Shark Screw).

Clinical and Radiological Comparison of Hallux Valgus Correction Using the Metal Screw or the Human Allogeneic Cortical Bone Screw, a Prospective Study

The goal of this clinical trial is to compare the treatment of Hallux Valgus using the conventional method (metal screw) with the new method (human allogeneic cortical bone screw (Shark Screw®) in adult patients with confirmed Hallux Valgus.

The main questions it aims to answer are:

Can the new method obtain comparable results as the conventional method in regard to union rate and time to union? Are the number of complications lower with the new method? Participants will be operated either with the metal screw or with the Shark Screw®. The assignment to the groups is randomized.

The planned prospective study will investigate whether the use of the human allogenic cortical bone screw (Shark Screw® leads to comparable results in the union rate and the prevention of recurrences as with metal screws. Furthermore, it will be investigated whether rotational stability is possible with the bone screw. The measurement of the HVA angle and the IMA angle should provide information on whether the correction is stable over time. A comparison of the AOFAS forefoot score before and after the operation for both methods is a further measure to check whether the human allogenic cortical bone screw can deliver similar results.

Initial studies on the use of the allogenic bone screw in hand and foot surgery show particularly good integration behavior of the human allogenic cortical bone screw . A retrospective study by Hanslik-Schnabel et al has shown initial positive results in the treatment of hallux rigidus. In addition, a gait analysis is performed pre- and postoperatively to provide information on possible differences between the two groups in the context of 3D gait analysis/pedobarography and is also matched with another healthy cohort.

At the preoperative time point and after 12 and 24 months, a 3D gait analysis with a foot model is conducted to record the joint kinematics and kinetics. In the study by Canseco et al. , the proximal gait pattern changes remained unchanged. Hwang reported hyper-external rotation in the subtalar joint, excessive eversion in the subtalar joint, and lack of movement in the hallux MP joint in the terminal standing phase.

Inclusion Criteria:

• between 18 and 85
• confirmed Hallux Valgus

Exclusion Criteria:

• <18 years and >85 years
• Known underlying oncological disease
• Pregnant women or breastfeeding mothers
• Alcohol and drug abuse
• Foreseeable compliance problems
• Foreseeable loss of responsibility as a study doctor
• Neoplastic diseases
• Active osteomyelitis
• Ulcerations in the area of the skin of the surgical site
• Immunosuppressive medication that cannot be discontinued