Does spiked tibial cement spacer reduce spacer-related problems in two-stage revision total knee arthroplasty for infection?

Clinical outcomes of two-stage revision arthroplasty using a spiked tibial cement spacer in infected total knee arthroplasty

PURPOSE

A tibial cement spacer (TCS) with spikes offers better initial stability than a conventional TCS and reduces spacer-related problems in two-stage revision total knee arthroplasty (R-TKA) for infection. We compared the clinical outcomes of two-stage revision arthroplasty for infected TKA using spiked TCS with that of conventional TCS.

METHODS

This retrospective cohort study included 29 patients who underwent two-stage revision arthroplasty using an articulating cement spacer and who could be followed up for at least one year. Group S comprised 14 patients using spiked TCS, whereas Group C comprised 15 patients using conventional TCS. Demographic data, the interval from first to second stage revision, motion arc, numerical rating scale (NRS), Knee Society (KS) score, serum levels of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and frequency of repeating the first-stage and infection recurrence after R-TKA between the groups were analyzed.

RESULTS

No significant differences were observed in the female ratio and mean age between both groups. The mean interval between the first and second stage revision was significantly shorter in Group S than in Group C. The mean motion arc was significantly larger in Group S than in Group C. The mean NRS was significantly lower in Group S than in Group C. The mean KS score in Group S was significantly higher than that in Group C. Serum ESR and CRP levels did not differ between the groups. The frequency of repeating the first stage was lower in Group S than in Group C. However, the recurrence rate after R-TKA was higher in Group S than in Group C.

CONCLUSION

Compared with conventional TCS, spiked TCS shortened the period until R-TKA and improved pain and function levels. However, no significant difference existed in the rate of infection recurrence after R-TKA.

Effect of Surgeon Volume on Mechanical Complications after Resection Arthroplasty with Articulating Spacer

Two-stage revision with an antibiotic-loaded cement articulating spacer is a standard treatment for chronic prosthetic knee infection (PKI); however, mechanical complications can occur during the spacer period. There is limited evidence on the association between surgeon volume and mechanical complications after resection arthroplasty (RA) using an articulating spacer. This study aimed to compare the rates of mechanical complications and reoperation after RA with articulating spacers by surgeons with high volumes (HV) and low volumes (LV) of RA performed and analyzed the risk factors for mechanical failure. The retrospective study investigated 203 patients treated with PKIs who underwent RA with articulating spacers and were divided according to the number of RAs performed by the surgeons: HV (≥14 RAs/year) or LV (<14 RAs/year). Rates of mechanical complications and reoperations were compared. Risk factors for mechanical complications were analyzed. Of the 203 patients, 105 and 98 were treated by two HV and six LV surgeons, respectively. The mechanical complication rate was lower in HV surgeons (3.8%) than in LV surgeons (36.7%) (p < 0.001). The reoperation rate for mechanical complications was lower in HV surgeons (0.9%) than in LV surgeons (24.5%) (p < 0.001). Additionally, 47.2% of patients required hinge knees after mechanical spacer failure. Medial proximal tibial angle < 87°, recurvatum angle > 5°, and the use of a tibial spacer without a cement stem extension were risk factors for mechanical complications. Based on these findings, we made the following three conclusions: (1) HV surgeons had a lower rate of mechanical complications and reoperation than LV surgeons; (2) mechanical complications increased the level of constraint in final revision knee arthroplasty; and (3) all surgeons should avoid tibial spacer varus malalignment and recurvatum deformity and always use a cement stem extension with a tibial spacer.

Are Static Spacers Superior to Articulated Spacers in the Staged Treatment of Infected Primary Knee Arthroplasty? A Systematic Review and Meta-Analysis

In the treatment of knee periprosthetic joint infection with a two-stage protocol, static spacers allow for the local delivery of high doses of antibiotics and help to preserve soft tissue tension. Articulated spacers were introduced to better preserve flexion after the reimplantation. The aim of this systematic review is to provide a comprehensive data collection of the results of these different spacers. An in-depth search on the main clinical databases was performed concerning the studies reporting data on the topic. A total of 87 studies and 4250 spacers were included. No significant differences were found both in pooling data analysis and meta-analysis of comparative studies about infection recurrences, complications, and clinical scores. Mean active knee flexion at last follow-up after total knee reimplantation was found to be significantly higher using articulated spacers (91.6° ± 7° for static spacers vs. 100.3° ± 9.9° for articulated spacers; p < 0.001). Meta-analysis also recognized this strong significant difference (p < 0.001). This review has confirmed that articulated spacers do not appear to be inferior to static spacers regarding all clinical outcomes, while they are superior in terms of active flexion. However, the low quality of the studies and the risk for selection bias with complex patients preferentially treated with static spacers need to be accounted for.