Iliotibial band traction syndrome in guided motion TKA. A new clinical entity after TKA.

This study aimed at systematic documentation of lateral knee pain in a consecutive series of 1102 cruciate-substituting, guided motion total knee arthroplasties (TKA) (Journey, Smith and Nephew, Memphis, TN, USA) performed in 1085 patients; 1070 knees were available for review. Follow-up time ranged from one to five years, with a mean of 2.5 years. Symptoms mimicking the well known iliotibial band (ITB) friction syndrome were observed in 77 knees (7.2%). Initial conservative treatment consisted of anti-inflammatory medication (77 knees) and local steroid injection (35 knees). The pain persisted in 22 knees (2%), leading to a surgical release of the iliotibial band. Other surgical interventions included revision for infection (6 knees, 0.5%), revision for tibial component loosening (6 knees, 0.5%), revision for tibiofemoral dislocation (3 knees, 0.3%), revision for patellar component loosening (5 knees, 0.4%), revision for instability (1 knee, 0.1%) and secondary patellar resurfacing (1 knee, 0.1%). The overall survivorship with partial or total implant revision as an endpoint was 98%. The development of lateral knee pain in association with the use of a guided motion design can be explained by the forced posterior translation of the lateral condyle in flexion. The asymmetric cam and post mechanism, acting as a hard driver of posterior femoral translation and internal tibial rotation during flexion, does not allow for the natural kinematic variability occurring in native knees. This repetitive and forced stretching of the ITB seems to induce a painful traction syndrome in some patients.