Soft tissue balance in total knee arthroplasty: Clinical value of intra-operative measurement

Purpose:

Considering successful clinical outcomes, accurate osteotomy/implantation and soft tissue balancing are essential in total knee arthroplasty (TKA). However, intra-operative assessment of soft tissue balance remains difficult, and management is left much to the surgeon's subjective feel and experience. The aim of this paper was to review various soft tissue balance assessments and their relationship with pre- and intra-operative factors and clinical outcomes.

Methods:

Literature regarding the history of soft tissue balance measurement, various types of measurement tools, theory of recent measurement, influence of various factors on soft tissue balance, and influence of soft tissue balance on clinical outcomes in TKA was reviewed using the PubMed database.

Results:

Soft tissue balance measurement has switched from the unphysiological condition, i.e., with assessment between bone cut surfaces and patellar eversion, to the physiological condition, i.e. with femoral component placement and patellofemoral joint reduction. Type of prosthesis, implant design, surgical technique, and pre-operative factors affect intra-operative soft tissue balance. Intra-operative soft tissue balance also affects post-operative range of motion and patient-reported outcome measures.

Conclusions:

Intra-operative quantitative soft tissue balance measurement and management with physiological knee condition, which is closely influenced by various pre-operative and intra-operative factors, is important for the achievement of high knee function and patient satisfaction.