Ac. Stahelin et al., CLINICAL DEGRADATION AND BIOCOMPATIBILITY OF DIFFERENT BIOABSORBABLE INTERFERENCE SCREWS - A REPORT OF 6 CASES, Arthroscopy, 13(2), 1997, pp. 238-244
The clinical biocompatibility and degradation of bioabsorbable interfe
rence screws of different polymer composition is described in this rep
ort for six patients who underwent repeat arthroscopy after anterior c
ruciate ligament (ACL) reconstruction. Bioabsorbable interference scre
ws were used for bone plug fixation of bone-patellar tendon-bone (BPTB
) autografts. Poly (L-lactide) (PLLA) interference screws were used in
one case, poly (D,L-lactide-co-glycolide) (PDLLA-co-PGA) in two cases
and poly (D,L-lactide) (PDLLA) in three cases. The patients either un
derwent removal of the femoral screw or had a biopsy taken from the sc
rew site during re-arthroscopy. Large fragments of the PLLA screw were
still present 20 months postoperatively. In one case, the PDLLA-co-PG
A screw was extruded spontaneously from the tibial bone tunnel 3 weeks
after the operation. In the second PDLLA-co-PGA screw case, there was
no evidence left of the screw material on biopsy 12 months after impl
antation. The PDLLA screw in one patient was removed 6 weeks after imp
lantation without any signs of degradation. No traces of the PDLLA scr
ews were found in the two other patients, 10 or 14 months postoperativ
ely. There were no clinical signs of foreign-body reactions in all cas
es.