ABSTRACT
BACKGROUND: For arthrodesis of the tarsometatarsal joints, there is the possibility of using a transplant screw made of allogenic human bone material (Shark Screw). This article investigates the clinical outcome and radiologic integration of the allogenic bone screw for arthrodesis of the tarsometatarsal joints II/+III. METHODS: This is a prospective study involving 20 feet of 17 patients who received TMT II/+III arthrodesis with an allogenic bone screw. A visual analog scale (VAS pain and function), Foot Function Index (FFI), American Orthopaedic Foot & Ankle Society (AOFAS) midfoot score, and Foot and Ankle Outcome Score (FAOS) were used as measures to compare preoperative with postoperative results. Radiologic integration in the recipient bone was also evaluated. RESULTS: A significant mean pre- to postoperative improvement of all evaluated scores has been observed (P < .05) after a mean follow-up of 15.87 months (minimum 12 months, maximum 33 months). VAS score (pain) decreased from 7.6 to 1.4 points as well as a decrease of the VAS (function) from 7.25 to 1.8 points. Further, a reduction of the FFI from 62.3% to 16.7% and an increase from 29.7 to 79.9 points of the AOFAS was detected. Analyzing the FAOS score, in all surveyed subscales, there was an increase in the score (Symptoms: 55.2 to 85.6 points; Pain: 30.5 to 86.9 points; Function: 33.1 to 88.3 points; Quality of life: 27.8 to 79.7 points). Moreover, in all cases, a complete radiologic integration into the receiving bone was appreciated, and after a minimum follow-up time from 12 months, the screw in 19 feet (95%) was no longer distinguishable from the original bone. CONCLUSION: With these first results of the allogenic bone screw in TMT II/+III arthrodesis, a significant improvement from preoperative to postoperative was confirmed in the collected scores, and a full radiographic integration was demonstrated in all feet.