A 10-year follow up of Arthroereisis screws in Adult Flat Foot Reconstruction

J Bhamra, A Fell, M Hashem, C Clark

Introduction: The use of an arthroereisis screw is well described in the paediatric population for the correction of flexible flat feet. There are no long-term studies of its use in adults. We performed a functional and radiographic evaluation of a single centre, single surgeon series following the use of a subtalar arthroereisis screw, to augment reconstruction in adult patients with acquired adult flat foot deformity secondary to spring ligament / tibialis posterior
tendon failure.

Methods: We performed a retrospective review of 40 consecutive feet with stage 2 PTTI that underwent flexor digitorum longus transfer, reefing of the spring ligament, translational medialising calcanaeal osteotomy and augmentation with an arthroereisis screw (Kalix, Integra; 22 feet or ProStop, Arthrex; 3 feet), between 2005 and 2021. All arthroereisis screws were electively removed at 6 months. Radiographic values were assessed pre- and postoperatively
at 1-year with functional results both at 1-year and average 10-year follow-up.

Results: The mean age of patients at surgery was 60 years (range 44-77 years). There was a significant improvement p<0.05) in radiographic parameters (calcaneal pitch, Mearys angle, medial column height, talus to 1st and 2nd metatarsal angle and talonavicular coverage). There were no re-operations. Manchester Oxford Foot Questionnaire, EQ-5D and VAS scores at an average of 10.6 years for pain were reported as 2.3 (range 0-64, Likert scale), 0.94 (range -0.59-1) and 0.2 (0-10), respectively. Health TODAY averaged at 91.4%.

Conclusion: We conclude that the use of an arthroereisis screw is a promising adjunct to conventional reconstruction in adult PTTI that protects the spring ligament repair and tendon transfer during the initial healing time of the soft tissues. Excellent radiological and functional results were obtained in our cohort with high levels of patient satisfaction at long-term follow-up.