Instability is a common indication for early
revision after both primary and revision total knee arthroplasty
(TKA), accounting for up to 20% in the literature. The number of
TKAs performed annually continues to climb exponentially, thus having
an effective algorithm for treatment is essential. This relies on
a thorough pre- and intra-operative assessment of the patient. The
underlying cause of the instability must be identified initially
and subsequently, the surgeon must be able to balance the flexion
and extension gaps and be comfortable using a variety of constrained
implants. This review describes the assessment of the unstable TKA, and
the authors’ preferred form of treatment for these difficult cases
where the source of instability is often multifactorial. Cite this article:
Although the vast majority of patients that undergo
total knee replacement have satisfactory outcomes with a generally
low complication rate, occasionally a patient will be encountered
that has had multiple failed surgeries, and now reaches a crossroad
as to whether limb salvage will be acceptable or not. Cite this article:
