CORR Insights: What Sports Activity Levels Are Achieved in Patients With Modular Tumor Endoprostheses of Osteosarcoma About the Knee?

T he current study by Hobusch et al. presented 27 sportsminded patients with osteosarcoma who had undergone successful limb salvage of the knee. Surgeons used modular knee endoprostheses (25 patients with fixed hinges, two patients with rotating hinges) to reconstruct the knees. The authors charted the sporting activities that the patients resumed after surgery compared to their prediagnosis sporting abilities. This retrospective study was done via chart review and telephone interview, and results were presented at an average followup time of 11.2 years. The results of the study found that two patients (7.4%) returned to high-impact sporting activities (soccer, jogging) and approximately more than one-third performed intermediate-impact activities (alpine skiing, fitness training) postsurgery. However, this study also poses a number of questions: Is there a risk to the limb and prosthesis in achieving some of these sporting activities? Is a rotating platform hinge knee more conducive to attempts at sporting activities than these fixed hinges or just more parts to wear and fail with excessive activity? The ultimate goal in tumor surgery for osteosarcoma of the knee is to save a life. The secondary goal is to save the limb. If those two goals are achieved, the final goal is to help the patient resume his or her routine daily living activities in ways that might be more advantageous than patients treated with the surgical alternative to these reconstructions, which is an above-knee-amputation. While there are inherent (and, to my eye, important) differences in how the extensor mechanism can be handled in distal femoral reconstructions compared to proximal tibial reconstructions, the authors did not find any sport-related functional differences, and as such, the distal femur (16 patients) and proximal tibia (11 patients) reconstructions were reported together. The authors specifically mentioned a 51% revision rate, but did not attribute this to sports activities. Revisions were performed for soft tissue failure in eight patients, aseptic loosening of the press fit This CORR Insights is a commentary on the article ‘‘What Sports Activity Levels Are Achieved in Patients With Modular Tumor Endoprostheses of Osteosarcoma About the Knee? ’’ by Lang and colleagues available at: DOI: 10.1007/s11999-014-3788-2. The author certifies that he, or any member of his immediate family, has no funding or commercial associations (eg, consultancies, stock ownership, equity interest, patent/ licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research editors and board members are on file with the publication and can be viewed on request. The opinions expressed are those of the writers, and do not reflect the opinion or policy of CORR or the Association of Bone and Joint Surgeons. This CORR Insights comment refers to the article available at DOI: 10.1007/s11999-0143788-2. M. J. Joyce MD (&) Orthopaedic and Rheumatology Institute, Cleveland Clinic, 9500 Euclid Avenue/A41, Cleveland, OH 44195, USA e-mail: joycem@ccf.org CORR Insights Published online: 20 August 2014 The Association of Bone and Joint Surgeons1 2014