Use of HA–PLLA Composite Screws to Fix Acetabular Bone Graft in Cemented THA: Absorption Pattern of Screws in Six Patients
We used a composite of uncalcined and unsintered hydroxyapatite (u-HA) particles and poly-l-lactide (PLLA) to fix the acetabular bone graft in total hip arthroplasty (THA) in a clinical trial in six patients, and followed them for over 10 years. The patients were evaluated clinically and radiologically to assess the safety and efficacy of the screws and the characteristics of their absorption. No patient in this series experienced revision or radiographic loosening during the follow-up period. The configurations of the HA–PLLA composite screws were confirmed on early post-operative radiographs in every case, whereas they appeared obscure on radiographs within 5 years after surgery, and only osteosclerotic traces remained in the screw positions at the final follow-up. Some screw heads were covered with bone within 3 months of surgery, and some screw heads migrated laterally with breakage, but were absorbed in situ within 5 years. The screws seemed to have no negative effect on the mid-term clinical results of the THAs.
Eyup Sabri Kayali, Gultekin Goller and Ipek Akin
K. Goto et al., "Use of HA–PLLA Composite Screws to Fix Acetabular Bone Graft in Cemented THA: Absorption Pattern of Screws in Six Patients", Key Engineering Materials, Vols. 493-494, pp. 422-425, 2012