Outcome after Knee Arthrodesis for Failed Septic Total Knee Replacement Using a Monolateral External Fixator

Abstract

purpose. To evaluate the pain level and patient satisfaction as well as the fusion and infection eradication rates after knee arthrodesis using a monolateral external fixator for failed septic total knee replacement (TKR). Methods. Records of 10 male and 11 female consecutive patients aged 70 to 88 (mean, 81) years who underwent knee arthrodesis using a monolateral external fixator for failed septic TKR were retrospectively reviewed. Each patient had undergone a mean of 3.4 (range, 1-15) procedures. The infection eradication rate, fusion rate, time to achieve fusion, pain level, patient satisfaction, and health-related quality of life were evaluated. results. Infection was eradicated in 18 (86%) of the 21 patients, whereas fusion was achieved in 17 (81%) of the 21 patients after a mean of 10.3 (range, 4-16) months. Those who did and did not achieve fusion differed significantly in terms of the mean pain score (2.3 vs. 6.4, p=0.031). Compared with age-matched Outcome after knee arthrodesis for failed septic total knee replacement using a monolateral external fixator Journal of Orthopaedic Surgery 2013;21(3):275-80Spanish general population, patients aged >75 years fared significantly worse in terms of the mean physical summary component score (40.7 vs. 34.9, p=0.001). Among those who achieved fusion, 82% were very or somewhat satisfied; none was very dissatisfied. Among those who did not achieve fusion, 75% were very or somewhat dissatisfied. conclusion. Knee arthrodesis using a monolateral external fixator for failed septic TKR achieved high fusion and infection eradication rates, despite the extended time needed. When fusion is achieved, patients had good pain relief and satisfaction.

Modern Techniques in Knee Arthrodesis

“…Although LLD was comparable to another recent study, the wide range of fusion rates reported in the literature, regarding the use of a monolateral external fixator, makes it difficult to accurately assess how this study compares, to other techniques, in this aspect (range of 28.6%-87.5%) [8,12,38] (Table 1). Those who did and did not achieve fusion differed significantly in regards to their pain score as well as their satisfaction rates (82% vs 75% respectively) [35] . Watanabe et al found a similar fusion rate of 87.5% in 8 patients who underwent monolateral external fixation following an infected TKA.…”

“…The frame is placed based on the position of the skin incision, which is done either anterolaterally or anteromedially [3,35] . Although compression and bending stiffness is adequate along these planes, there have been reports of reduced stability along the mediolateral aspect [3,36,37] .…”

Salvage Procedures for Management of Prosthetic Joint Infection After Hip and Knee Replacements

“…Different designs have also been used for EF. These included the Hoffman EF with multiplanar pin insertion [72], the Ilizarov or circular ring fixators [73-76], unilateral EFs [77, 78], hybrid EFs [79] and a combination of EF and Steinmann pin application [80]. …”

“…Monolateral EF was associated with worse functional outcomes in patients older than 75 years of age [78]. Using pulsing electromagnetic field to enhance arthrodesis was found to promote union only in the early postoperative phase.…”

“…Of the most commonly used techniques, EF was associated with the lowest re-infection rates with no recurrence seen in 4 studies [73-75, 97] and recurrence rates ranging from 14 - 17.7% in 3 other studies [79, 78, 80]. On the other hand, re-infection rates ranged from 3 - 28.6% for IMNs.…”