Kristoff Hammerich1, Jens Pollack2, Alexander F Hasse3, André El Saman4, René Huber5,6, Markus Rupp7, Volker Alt7, Raimund W Kinne5, Joerg Mika5. 1. Department of Orthopaedic Surgery, Eichsfeld Klinikum gGmbH, Academic Teaching Hospital of the University of Goettingen, 37308 Heilbad Heiligenstadt, Germany. 2. Department of Orthopaedic Surgery, SRH Wald-Klinikum Gera, Academic Teaching Hospital of the University of Jena, 07548 Gera, Germany. 3. Department of Internal Medicine 1, Section of Hematology/Oncology/Rheumatology, University Hospital Homburg, 66421 Homburg, Germany. 4. Department of Trauma, Hand and Reconstructive Surgery, University Hospital Frankfurt, 60590 Frankfurt am Main, Germany. 5. Experimental Rheumatology Unit, Department of Orthopedics, Jena University Hospital, Waldkliniken Eisenberg GmbH, 07607 Eisenberg, Germany. 6. Institute of Clinical Chemistry, Hannover Medical School, 30625 Hannover, Germany. 7. Department of Trauma Surgery, University Hospital Regensburg, 93053 Regensburg, Germany.
Abstract
BACKGROUND: A major disadvantage of current spacers for two-stage revision total knee arthroplasty (R-TKA) is the risk of (sub-) luxation during mobilization in the prosthesis-free interval, limiting their clinical success with detrimental consequences for the patient. The present study introduces a novel inverse spacer, which prevents major complications, such as spacer (sub-) luxations and/or fractures of spacer or bone. METHODS: The hand-made inverse spacer consisted of convex tibial and concave femoral components of polymethylmethacrylate bone cement and was intra-operatively molded under maximum longitudinal tension in 5° flexion and 5° valgus position. Both components were equipped with a stem for rotational stability. This spacer was implanted during an R-TKA in 110 knees with diagnosed or suspected periprosthetic infection. Postoperative therapy included a straight leg brace and physiotherapist-guided, crutch-supported mobilization with full sole contact. X-rays were taken before and after prosthesis removal and re-implantation. RESULTS: None of the patients experienced (sub-) luxations/fractures of the spacer, periprosthetic fractures, or soft tissue compromise requiring reoperation. All patients were successfully re-implanted after a prosthesis-free interval of 8 weeks, except for three patients requiring an early exchange of the spacer due to persisting infection. In these cases, the prosthetic-free interval was prolonged for one week. CONCLUSION: The inverse spacer in conjunction with our routine procedure is a safe and cost-effective alternative to other articulating or static spacers, and allows crutch-supported sole contact mobilization without major post-operative complications. Maximum longitudinal intra-operative tension in 5° flexion and 5° valgus position appears crucial for the success of surgery.
BACKGROUND: A major disadvantage of current spacers for two-stage revision total knee arthroplasty (R-TKA) is the risk of (sub-) luxation during mobilization in the prosthesis-free interval, limiting their clinical success with detrimental consequences for the patient. The present study introduces a novel inverse spacer, which prevents major complications, such as spacer (sub-) luxations and/or fractures of spacer or bone. METHODS: The hand-made inverse spacer consisted of convex tibial and concave femoral components of polymethylmethacrylate bone cement and was intra-operatively molded under maximum longitudinal tension in 5° flexion and 5° valgus position. Both components were equipped with a stem for rotational stability. This spacer was implanted during an R-TKA in 110 knees with diagnosed or suspected periprosthetic infection. Postoperative therapy included a straight leg brace and physiotherapist-guided, crutch-supported mobilization with full sole contact. X-rays were taken before and after prosthesis removal and re-implantation. RESULTS: None of the patients experienced (sub-) luxations/fractures of the spacer, periprosthetic fractures, or soft tissue compromise requiring reoperation. All patients were successfully re-implanted after a prosthesis-free interval of 8 weeks, except for three patients requiring an early exchange of the spacer due to persisting infection. In these cases, the prosthetic-free interval was prolonged for one week. CONCLUSION: The inverse spacer in conjunction with our routine procedure is a safe and cost-effective alternative to other articulating or static spacers, and allows crutch-supported sole contact mobilization without major post-operative complications. Maximum longitudinal intra-operative tension in 5° flexion and 5° valgus position appears crucial for the success of surgery.
Authors: Tahir Mahmud; Matthew C Lyons; Douglas D Naudie; Steven J Macdonald; Richard W McCalden Journal: Clin Orthop Relat Res Date: 2012-10 Impact factor: 4.176
Authors: Aaron J Johnson; Siraj A Sayeed; Qais Naziri; Harpal S Khanuja; Michael A Mont Journal: Clin Orthop Relat Res Date: 2012-01 Impact factor: 4.176
Authors: S P Boelch; A Jakuscheit; S Doerries; L Fraissler; M Hoberg; J Arnholdt; M Rudert Journal: BMC Musculoskelet Disord Date: 2018-11-10 Impact factor: 2.362