BACKGROUND: Extensor mechanism disruption (EMD) combined with periprosthetic joint infection (PJI) after total knee arthroplasty are life-changing complications. The literature suggests many eventually receive above-knee amputation and lose ambulatory function. An alternative is modular knee fusion (KF), but little is known about its outcomes and biomechanical function. We report early term results on a case series of patients. METHODS: A retrospective review was conducted of patients who underwent 2-stage reconstruction with modular KF for combined EMD and PJI. Patient-reported outcomes at 1 year after arthrodesis and complications of surgery were recorded. Biomechanical analysis was conducted on 6 patients >1 year after surgery to measure gait speed and balance. RESULTS: Fifteen patients received a modular KF. At the most recent follow-up visit (average 25.7 months), 12 patients had their modular KFs in place and were ambulatory while 2 had died. Six patients used a walker; 4, a cane; and 2, unassisted. Gait analysis of 6 of these patients showed variation in patterns and speed. Balance was better than historical controls treated with above-knee amputation. Average Knee Injury and Osteoarthritis Outcome Score Junior was 76 ± 11. CONCLUSION: Modular KF for EMD and PJI can result in successful outcomes in terms of preventing additional operations and maintaining ambulation. While speed is variable, physical testing shows this method for limb salvage may allow patients to ambulate with a gait aid although further studies are needed to evaluate midterm and long-term results.
BACKGROUND: Extensor mechanism disruption (EMD) combined with periprosthetic joint infection (PJI) after total knee arthroplasty are life-changing complications. The literature suggests many eventually receive above-knee amputation and lose ambulatory function. An alternative is modular knee fusion (KF), but little is known about its outcomes and biomechanical function. We report early term results on a case series of patients. METHODS: A retrospective review was conducted of patients who underwent 2-stage reconstruction with modular KF for combined EMD and PJI. Patient-reported outcomes at 1 year after arthrodesis and complications of surgery were recorded. Biomechanical analysis was conducted on 6 patients >1 year after surgery to measure gait speed and balance. RESULTS: Fifteen patients received a modular KF. At the most recent follow-up visit (average 25.7 months), 12 patients had their modular KFs in place and were ambulatory while 2 had died. Six patients used a walker; 4, a cane; and 2, unassisted. Gait analysis of 6 of these patients showed variation in patterns and speed. Balance was better than historical controls treated with above-knee amputation. Average Knee Injury and Osteoarthritis Outcome Score Junior was 76 ± 11. CONCLUSION: Modular KF for EMD and PJI can result in successful outcomes in terms of preventing additional operations and maintaining ambulation. While speed is variable, physical testing shows this method for limb salvage may allow patients to ambulate with a gait aid although further studies are needed to evaluate midterm and long-term results.
Authors: Brian P Chalmers; Alexis K Matrka; Stephen A Sems; Matthew P Abdel; Rafael J Sierra; Arlen D Hanssen; Mark W Pagnano; Tad M Mabry; Kevin I Perry Journal: Bone Joint J Date: 2020-06 Impact factor: 5.082
Authors: Edward J McPherson; Chris Woodson; Paul Holtom; Nikolaos Roidis; Chrissandra Shufelt; Michael Patzakis Journal: Clin Orthop Relat Res Date: 2002-10 Impact factor: 4.176
Authors: Sven Hungerer; Martin Kiechle; Christian von Rüden; Matthias Militz; Knut Beitzel; Mario Morgenstern Journal: BMC Musculoskelet Disord Date: 2017-11-13 Impact factor: 2.362
Authors: Arnold J Suda; Xaver Brachtendorf; Marco Tinelli; Raed Wagokh; Ghaith Abou-Nouar; Oliver E Bischel Journal: Int Orthop Date: 2021-04-23 Impact factor: 3.075