Retrospective Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Nov 18, 2015; 6(10): 829-837
Published online Nov 18, 2015. doi: 10.5312/wjo.v6.i10.829
Modified porous tantalum rod technique for the treatment of femoral head osteonecrosis
Emilios E Pakos, Panayiotis Megas, Nikolaos K Paschos, Spyridon A Syggelos, Antonios Kouzelis, Georgios Georgiadis, Theodoros A Xenakis
Emilios E Pakos, Nikolaos K Paschos, Georgios Georgiadis, Theodoros A Xenakis, Department of Orthopaedics and Biomechanics, University of Ioannina, Medical School, 45110 Ioannina, Greece
Panayiotis Megas, Antonios Kouzelis, Department of Orthopaedic Surgery, University Hospital of Patras, University of Patras, Medical School, 26504 Patras, Greece
Spyridon A Syggelos, Department of Anatomy, Histology, Embryology, University of Patras, Medical School, 26504 Patras, Greece
Author contributions: Pakos EE designed the research, performed the research, analysed the data and wrote the paper; Megas P performed the operations, designed and performed the research; Paschos NK wrote the paper and performed the language editing; Syggelos SA and Kouzelis A performed the research and wrote the paper; Georgiadis G wrote the paper; Xenakis TA performed the operations, designed and performed the research.
Institutional review board statement: This study was reviewed and approved by the Ethics Committees of the University Hospital of Ioannina and the University Hospital of Patras.
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: We have no financial relationships to disclose.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Emilios E Pakos, MD, PhD, Lecturer, Orthopaedic Surgeon, Department of Orthopaedics and Biomechanics, University of Ioannina, Medical School, P.O. Box 1186, 45110 Ioannina, Greece. epakos@yahoo.gr
Telephone: +30-265-1008099 Fax: +30-265-1008069
Received: May 25, 2015
Peer-review started: May 27, 2015
First decision: June 18, 2015
Revised: July 15, 2015
Accepted: September 7, 2015
Article in press: September 8, 2015
Published online: November 18, 2015
Abstract

AIM: To study a modified porous tantalum technique for the treatment of osteonecrosis of the femoral head.

METHODS: The porous tantalum rod was combined with endoscopy, curettage, autologous bone grafting and use of bone marrow aspirates from iliac crest aspiration in 49 patients (58 hips) with a mean age of 38 years. The majority of the patients had idiopathic osteonecrosis, followed by corticosteroid-induced osteonecrosis. Thirty-eight hips were of Steinberg stage II disease and 20 hips were of stage III disease. Patients were followed for 5 years and were evaluated clinically with the Merle D’Aubigne and Postel score and radiologically. The primary outcome of the study was survival based on the conversion to total hip arthroplasty (THA). Secondary outcomes included deterioration of the osteonecrosis to a higher disease stage at 5 years compared to the preoperative period and identification of factors that were associated with survival. The Kaplan-Meier survival analysis was performed to evaluate the survivorship of the prosthesis, and the Fisher exact test was performed to test associations between various parameters with survival.

RESULTS: No patient developed any serious intraoperative or postoperative complication including implant loosening or migration and donor site morbidity. During the 5-year follow up, 1 patient died, 7 patients had disease progression and 4 hips were converted to THA. The 5-year survival based on conversion to THA was 93.1% and the respective rate based on disease progression was 87.9%. Stage II disease was associated with statistically significant better survival rates compared to stage III disease (P = 0.04). The comparison between idiopathic and non-idiopathic osteonecrosis and between steroid-induced and non-steroid-induced osteonecrosis did not showed any statistically significant difference in survival rates. The clinical evaluation revealed statistically significantly improved Merle d’Aubigne scores at 12 mo postoperatively compared to the preoperative period (P < 0.001). The mean preoperative Merle d’Aubigne score was 13.0 (SD: 1.8). The respective score at 12 mo improved to 17.0 (SD: 2.0). The 12-mo mean score was retained at 5 years.

CONCLUSION: The modified porous tantalum rod technique presented here showed encouraging outcomes. The survival rates based on conversion to THA are the lowest reported in the published literature.

Keywords: Avascular necrosis, Femoral head, Tantalum rod, Survival, Bone grafting

Core tip: In the present study, we present the results of a modified porous tantalum technique for the treatment of femoral head avascular necrosis. The porous tantalum rod was combined with endoscopy, curettage, autologous bone grafting and use of bone marrow aspirates from iliac crest aspiration in 58 hips. The 5-year survival based on conversion to total hip arthroplasty was 93.1% and the respective rate based on disease progression was 87.9%. Stage II disease was associated with statistically significantly better survival rates compared to stage III disease, while no other factor was found to be associated with outcomes.