Fifty shades of knee instability: a commentary on “Repair of intraoperative injury to the medial collateral ligament during primary total knee arthroplasty”

Instability following total knee arthroplasty (TKA) can be the source of residual pain, swelling, and is a leading cause for early revision following knee replacement surgery (1). While the true definition and causes for instability are not well defined, intraoperative injury to the medial collateral ligament (MCL) without proper management can result in dysfunction and dissatisfaction following TKA.