Shuang G Yan1,2, Matthias Woiczinski1, Tobias F Schmidutz1,3, Patrick Weber1, Alexander C Paulus1, Arnd Steinbrück1, Volkmar Jansson1, Florian Schmidutz4,5. 1. Department of Orthopaedic Surgery, Physical Medicine and Rehabilitation, University of Munich (LMU), Marchioninistr. 15, 81377, Munich, Germany. 2. Anhui Medical University, The First Affiliated Hospital of Anhui Medical University, Anhui Sheng, China. 3. Physics Department Cavendish Laboratory, University of Cambridge, Cambridge, UK. 4. Department of Orthopaedic Surgery, Physical Medicine and Rehabilitation, University of Munich (LMU), Marchioninistr. 15, 81377, Munich, Germany. florian.schmidutz@med.uni-muenchen.de. 5. BG Trauma Center, University of Tübingen, Tübingen, Germany. florian.schmidutz@med.uni-muenchen.de.
Abstract
PURPOSE: Short stem total hip arthroplasty (SHA) has gained increasing popularity as it conserves bone stock and is supposed to allow revision with a conventional stem. However, no study has evaluated whether the revision of a SHA with a standard total hip arthroplasty (THA) stem provides sufficient primary stability to allow osseous integration. METHODS: A neck preserving SHA (Metha) and a standard THA (CLS) stem were implanted into six composite femurs respectively and dynamically loaded (300-1700 N, 1 Hz). Primary stability was evaluated by three dimensional-micromotions (3D micro motion) at five points of the interface. Then, a revision scenario was created by removing the SHA and using the same CLS stem as a revision implant (CLS-revision group), with subsequent evaluation of the 3D micro motion according to the primary CLS stem. RESULTS: The 3D micro motion pattern significantly differed in the primary situation between the short and the standard stem. The highest 3D micro motion were registered proximally for the Metha and distally for the CLS stem. Revising the Metha with a CLS stem revealed a bony defect at the calcar. However, the 3D micro motion of the CLS-revision group were not significant higher compared to those of the primary CLS stem. CONCLUSION: Our results show, that SHA (Metha) and standard THA (CLS) provide a good primary stability, however with different pattern of anchorage. The CLS stem reached a similar stability in this revision scenario as the CLS in the primary situation, wherefore it can be assumed that in uncomplicated revisions the Metha short stem can safely be revised with a CLS standard stem.
PURPOSE: Short stem total hip arthroplasty (SHA) has gained increasing popularity as it conserves bone stock and is supposed to allow revision with a conventional stem. However, no study has evaluated whether the revision of a SHA with a standard total hip arthroplasty (THA) stem provides sufficient primary stability to allow osseous integration. METHODS: A neck preserving SHA (Metha) and a standard THA (CLS) stem were implanted into six composite femurs respectively and dynamically loaded (300-1700 N, 1 Hz). Primary stability was evaluated by three dimensional-micromotions (3D micro motion) at five points of the interface. Then, a revision scenario was created by removing the SHA and using the same CLS stem as a revision implant (CLS-revision group), with subsequent evaluation of the 3D micro motion according to the primary CLS stem. RESULTS: The 3D micro motion pattern significantly differed in the primary situation between the short and the standard stem. The highest 3D micro motion were registered proximally for the Metha and distally for the CLS stem. Revising the Metha with a CLS stem revealed a bony defect at the calcar. However, the 3D micro motion of the CLS-revision group were not significant higher compared to those of the primary CLS stem. CONCLUSION: Our results show, that SHA (Metha) and standard THA (CLS) provide a good primary stability, however with different pattern of anchorage. The CLS stem reached a similar stability in this revision scenario as the CLS in the primary situation, wherefore it can be assumed that in uncomplicated revisions the Metha short stem can safely be revised with a CLS standard stem.
Entities:
Keywords:
3D; Anchorage; Initial fixation; Micromotion; SHA; Three dimensional
Authors: Josef Hochreiter; Wilfried Hejkrlik; Katja Emmanuel; Wolfgang Hitzl; Reinhold Ortmaier Journal: Int Orthop Date: 2016-12-10 Impact factor: 3.075
Authors: Harpal S Khanuja; Samik Banerjee; Deepak Jain; Robert Pivec; Michael A Mont Journal: J Bone Joint Surg Am Date: 2014-10-15 Impact factor: 5.284
Authors: Arnd Steinbrück; Alexander W Grimberg; Johanna Elliott; Oliver Melsheimer; Volkmar Jansson Journal: Orthopade Date: 2021-03-05 Impact factor: 1.087
Authors: Karl Philipp Kutzner; Stefanie Donner; Lennard Loweg; Philipp Rehbein; Jens Dargel; Philipp Drees; Joachim Pfeil Journal: J Orthop Traumatol Date: 2019-10-31