Association Between Lithium Use and Periprosthetic Fracture After Total Hip Arthroplasty.

BACKGROUND

Periprosthetic fracture (PPFx) is a devastating complication following total hip arthroplasty (THA), with concern for higher risk in osteoporotic patients. Lithium is associated with higher bone mineral density, and has emerged as a potential low-cost, widely available method for preventing fractures, promoting fracture healing, and improving implant osseointegration. This study investigated the association between lithium use and risk of PPFx following THA.

METHODS

Retrospective review of the PearlDiver Mariner Patient Claims Database was performed, querying all patients who underwent THA for osteoarthritis from 2010 to 2022. Lithium-use patients were those who filled lithium prescriptions for at least 90 days before and 90 days after THA. These patients were propensity-score matched to controls not on lithium in a 1:4 ratio, matching for age, diagnosis of bipolar disorder, gender, body mass index, Charlson Comorbidity Index, and insurance. PPFx rate was compared between groups at 90 days and 2 years postoperatively. Secondarily, rate of aseptic loosening, revision, and prosthetic joint infection were compared between groups.

RESULTS

Four thousand six hundred seventy patients were included, with 934 patients on lithium and 3736 controls. There was no difference in PPFx rate (90 day: lithium 1.3% vs no lithium 1.2%, P = .97; 2 year: lithium 1.7% vs no lithium 1.9%, P = .93), aseptic loosening, revision, or prosthetic joint infection.

CONCLUSIONS

Despite the theoretical benefit of lithium on bone density, it was not associated with a difference in the rate of PPFx or other surgical complication following THA. Further work is needed to address treatment of osteoporosis and prevention of periprosthetic fracture in the arthroplasty population.