bioball® adapter system: a supportive modular tool for primary and revision hip arthroplasty
Background: Restoring native hip biomechanics, particularly femoral offset and leg length, can be challenging in both primary and revision total hip arthroplasty (THA). Instability due to insufficient soft-tissue tension and isolated acetabular revisions with a well-integrated femoral stem are common scenarios where standard implants may be inadequate.
Objective of the Article: This article presents the technical characteristics, indications, surgical technique, and clinical outcomes of the BioBall® modular taper adapter system as a solution for complex hip reconstruction.
Key Points / Core Message: The BioBall® system is a versatile adapter-head system that allows for intraoperative adjustment of neck length, offset, and femoral version. Its primary indication is in revision THA, particularly for isolated acetabular component exchange, where it facilitates biomechanical correction while retaining a well-fixed femoral stem. The system is available for various taper sizes and can be combined with different stem materials and head types. A critical step is the intraoperative assessment of the existing stem taper; the system is contraindicated for tapers with significant damage, such as palpable defects or material loss, as this increases failure risk. Surgeons must also consider the increased lever arm created by extra-long adapters, which can elevate stress on the implant, especially when used with modular revision stems.
Conclusion / Implications for Practice: The BioBall® modular adapter system is an effective tool that provides intraoperative flexibility to address complex biomechanical challenges in THA. It can prevent the need for a more extensive femoral stem revision, which is particularly beneficial in high-risk patients. While clinical studies report favorable long-term outcomes and low complication rates, meticulous surgical technique, including rigorous taper evaluation, is paramount to ensure successful and durable reconstruction.
