Summary

For patients who developed septic arthritis following ACL reconstruction, treatment outcomes were compared between those who underwent graft salvage versus those who underwent graft resection with or without subsequent revision ACL reconstruction.

Abstract

Background

Septic arthritis (SA) of the knee following anterior cruciate ligament reconstruction (ACLR) is a rare but potentially devastating condition. In certain cases, graft removal becomes necessary.

Purpose

Evaluate clinical, subjective, and radiological outcomes of patients with SA following ACLR and assess whether graft retention has superior clinical results compared to graft removal.

Study Design:
Case series.

Methods

All patients who were at least 12 months out from arthroscopic treatment of SA following isolated ACLR at our institution were eligible for inclusion. Patients were categorized into either group 1, patients with initial graft retention, or group 2, patients with initial graft removal. Group 2 was again subdivided into group 2a, patients with graft re-implantation, and group 2b, patients without graft re-implantation. Clinical, subjective and radiological assessment were obtained at follow-up including the IKDC knee examination form, KT-1000 measurements, WOMAC score, Lysholm score, and IKDC subjective evaluation as well as pre- and postoperative MRI.

Results

Of the 41 patients included, 33 patients (81%) were available for follow-up at a mean of 54.7 ± 24.4 months with average age of 28.4 ± 9.3 years. Patients from group 1 (n = 21) obtained significantly better results on objective assessment than patients from group 2 (n = 12) both on the objective IKDC score (Group 1 66.6% of patients normal or nearly normal; group 2 33.4% of patients normal or nearly normal; P = 0.047) and KT-1000 measurements (Group 1, 1.3 ± 1.0 mm; Group 2, 2.9 ± 1.5 mm; P=0.005). Group 1 also scored better than group 2 both on the Lysholm, IKDC Subjective, and WOMAC scores (P = 0.007, P = 0.011, and P = 0.069, respectively). Comparing group 2a and 2b, no statistical significance in outcomes could be detected (P-value ranging from 0.307 to 0.705), although patients with ACL graft re-implantation showed a clear tendency towards better results. MRI evaluation showed more frequently cartilage damage and meniscal tears among patients with graft resection compared to graft retention.

Conclusions

Patients with graft retention showed superior postoperative results compared to patients who underwent initial graft resection, although subanalysis showed comparable outcomes between graft retention and reimplantation. Thus, while graft-retaining protocols should have the highest priority in the treatment of SA after ACLR, graft re-implantation should be performed in cases were graft resection becomes necessary to avoid future cartilage and meniscal lesions. Finally, further studies with larger numbers of patients are needed to gain a better understanding of the outcomes of patients with SA following ACLR.