The use of biocomposite vented anchors for arthroscopic remplissage allows for better bony ingrowth than peek vented anchors: A volumetric CT study of 85 anchors.

PURPOSE: To evaluate whether the use of polyetheretherketone (PEEK) or biocomposite vented anchors has any impact on bony ingrowth inside the anchor or implant-related osteolysis after implantation during remplissage for Hill-Sachs defects (HSD) in patients with shoulder instability.

METHODS

Prospective cohort study with a minimum of 24 months follow-up (mean follow-up 3.11[SD = 0.67] years). Forty-nine subjects (43 males and 6 females; mean age 27.6[SD:9.22] years) with HSD undergoing remplissage were evaluated with a CT performed at a mean of 14.7[4,4] months after surgery. The procedures were performed in two cohorts: in the first, 44 anchors (4.5 mm Healicoil PEEK) were used in 26 subjects. In the second, 41 anchors (4.75 mm Healicoil Regenesorb biocomposite) were used in 21 subjects. A computed tomography evaluation of the volume of the bone defects and the degree of bony ingrowth was made.

RESULTS

Preoperatively both cohorts were homogenous. The biocomposite anchors showed better bony ingrowth than the PEEK anchors (p = 0.0014): full bony ingrowth in 18/41(44%) in biocomposite versus 13/44(30%) in PEEK; clear ossification with a thin lucent rim in 15/41(37%) biocomposite versus 7/44(30%) PEEK; discontinuous ossification in 6/41(15%) biocomposite versus 7/44(16%) PEEK; and no ossification in 2/41(5%) biocomposite versus 17/44(39%) PEEK. The biocomposite anchors showed smaller bone defects than the PEEK anchors (p = 0.0217): no bone defect in 18/41(44%) biocomposite versus 13/44(30%) PEEK, partial bone defects in 20/41(49%) biocomposite versus 17/44(39%) PEEK; and bone defects larger than the insertion hole in 2/41(5%) biocomposite versus 13/44(30%) PEEK. One anchor in each group caused a bone defect larger than twice the size of the hole (2%). At the latest follow-up no differences in clinical outcomes between the groups were found.

CONCLUSION

Biocomposite vented anchors for remplissage favours bony ingrowth and lower the incidence of osteolysis and defect formation when compared to PEEK anchors with similar clinical outcomes.

LEVEL OF EVIDENCE: Level II, prospective cohort study.