Total knee arthroplasty in patient with poliomyelitis sequelae: maintaining a recurvatum is associated with better...

Total knee arthroplasty (TKA) in patients with sequelae of poliomyelitis is a surgical challenge due to muscle weakness, bone deformities or post-polio syndrome (PPS). Few data exist to determine the factors contributing to poor functional results. This study aimed: (1) to describe a cohort of patients with poliomyelitis sequelae who underwent TKA; (2) to examine risk factors for poor functional outcome.

A monocentric retrospective cohort study of all patients with poliomyelitis sequelae who underwent TKA between January 2006 and December 2019. Clinical, functional outcomes, radiographic results and occurrence of complications were collected.

A total of 22 patients (24 knees) were included in the analysis, with a mean follow-up of 6.6 years (from 2 to 13.7 years). There was an improvement in KSS (28 +/- 23 vs. 81 +/- 6, respectively; p < 0.0001) as well as functional KSS (25 +/- 12 vs. 57.5 +/- 21, respectively; p = 0.0001). There was less occurrence of annual knee giving way episodes after total knee replacement (11.9+/-16.1 vs. 5.1+/-13.7, respectively; p = 0.04). Even though the total knee replacement allowed a slight recurvatum, it was smaller than the preoperative recurvatum (13° vs. 8°, respectively; p = 0.04). Seven complications with reintervention (7/24; 29%) were found. The presence of a residual post operative recurvatum correlated with better KSS (ρ = 0.53, CI95% [0.15; 0.77]; p = 0.008). The number of postoperative annual knee giving way episodes was inversely correlated with persistent postoperative recurvatum (ρ = -0.42, CI95% [-0.69; -0.01]; p = 0.04) but was not correlated with the type of constraint (ρ = -0.26, CI95% [-0.6; 0.15]; p = 0.21) nor with quadricipital muscle strength (ρ = 0.21, CI95% [-0.21; 0.56]; p = 0.33).

TKA has a good mid-term functional outcome for knee osteoarthritis in patients with sequelae of poliomyelitis. Preserving a residual recurvatum postoperatively gives better clinical results without increasing the risk of ligament instability or early aseptic loosening.

IV.