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Piovan G, Bori E, Padalino M, Pianigiani S, Innocenti B. Biomechanical analysis of patient specific cone vs conventional stem in revision total knee arthroplasty. J Orthop Surg Res 2024; 19:439. [PMID: 39068461 PMCID: PMC11282788 DOI: 10.1186/s13018-024-04936-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Accepted: 07/21/2024] [Indexed: 07/30/2024] Open
Abstract
BACKGROUND In revision total knee arthroplasty, addressing significant bone loss often involves the use of cemented or press-fit stems to ensure implant stability and long-term fixation. A possible alternative to stem was recently introduced utilizing custom-made porous metaphyseal cones, designed to reconstruct the missing tibial and femoral geometries. Early clinical and radiological assessments have shown promising results. The objective of this research was to biomechanically evaluate the performances of these custom-made cones. METHODS The biomechanical study was conducted using a validated finite element model. The bone geometries of a patient (selected for their history of four knee revisions due to infection and periprosthetic fractures, followed by a successful treatment with custom-made 3D-printed metaphyseal cones) were employed for the study. On these bone models, different revision scenarios were simulated and examined biomechanically: (A) custom-made cementless metaphyseal cones; (B) cemented stems; (C) press-fit stems; (D) distal femoral reconstruction with press-fit stem. All the models were analyzed at 0 °and 90 °of flexion, under physiological load conditions simulating daily activities; stress distribution, average Von-Mises stresses and risk of fracture were then analyzed and compared among configurations. RESULTS The use of custom-made 3D-printed cones exhibited the most favorable stress distribution in both femoral and tibial bones. Tibial bone stress was evenly distributed in custom-made cone configurations, while stress concentration was observed in distal regions for the other scenarios. Additionally, custom-made cones displayed overall homogeneity and lower stress levels, potentially contributing to limit pain. Symmetrical stress distribution was observed between the lateral and medial proximal tibia in custom-made cone models, whereas other scenarios exhibited uneven stress, particularly in the anterior tibial bone. CONCLUSIONS The biomechanical analysis of porous custom-made metaphyseal cones in re-revision arthroplasties is in agreement with the positive clinical and radiological outcomes. These findings provide valuable insights into the potential benefits of using custom-made cones, which offer more uniform stress distribution and may contribute to improve patient outcomes in revision TKA procedures. Further studies in this direction are warranted to validate these biomechanical findings.
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Affiliation(s)
- Gianluca Piovan
- Department of Orthopaedic and Traumatology, S. Cuore-Don Calabria Hospital, Negrar, Italy
| | - Edoardo Bori
- BEAMS Department (Bio Electro and Mechanical Systems), École Polytechnique de Bruxelles, Université Libre de Bruxelles, Av. F. Roosevelt, 50 CP165/56, Brussels, 1050, Belgium
- Département ECAM, Haute Ecole ICHEC-ECAM-ISFSC, Woluwe-Saint-Lambert, Belgium
| | - Marika Padalino
- BEAMS Department (Bio Electro and Mechanical Systems), École Polytechnique de Bruxelles, Université Libre de Bruxelles, Av. F. Roosevelt, 50 CP165/56, Brussels, 1050, Belgium
| | - Silvia Pianigiani
- BEAMS Department (Bio Electro and Mechanical Systems), École Polytechnique de Bruxelles, Université Libre de Bruxelles, Av. F. Roosevelt, 50 CP165/56, Brussels, 1050, Belgium
- Adler Ortho, Cormano, Milan, 20032, Italy
| | - Bernardo Innocenti
- BEAMS Department (Bio Electro and Mechanical Systems), École Polytechnique de Bruxelles, Université Libre de Bruxelles, Av. F. Roosevelt, 50 CP165/56, Brussels, 1050, Belgium.
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Cianni L, Taccari F, Bocchi MB, Micheli G, Sangiorgi F, Ziranu A, Fantoni M, Maccauro G, Vitiello R. Characteristics and Epidemiology of Megaprostheses Infections: A Systematic Review. Healthcare (Basel) 2024; 12:1283. [PMID: 38998818 PMCID: PMC11241048 DOI: 10.3390/healthcare12131283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 05/18/2024] [Accepted: 06/18/2024] [Indexed: 07/14/2024] Open
Abstract
BACKGROUND Megaprostheses were first employed in oncological orthopedic surgery, but more recently, additional applications have arisen. These implants are not without any risks and device failure is quite frequent. The most feared complication is undoubtedly the implants' infection; however, the exact incidence is still unknown. This systematic review aims to estimate in the current literature the overall incidence of megaprosthesis infections and to investigate possible risk/protective factors. METHODS We conducted a systematic search for studies published from July 1971 to December 2023 using specific keywords. To be included, studies needed to report either the megaprosthesis anatomical site, and/or whether the megaprosthesis was coated, and/or the surgical indication as oncological or non-oncological reasons. RESULTS The initial literature search resulted in 1281 studies. We evaluated 10,456 patients and the overall infection rate was 12%. In cancer patients, the infection rate was 22%, while in non-oncological patients, this was 16% (trauma 12%, mechanical failure 17%, prosthetic joint infections 26%). The overall infection rates comparing coated and uncoated implants were 10% and 12.5%, respectively. CONCLUSIONS The number of megaprosthesis implants is increasing considerably. In traumatological patients, the infection rate is lower compared to all the other subgroups, while the infection rate remains higher in the cancer patient group. As these devices become more common, focused studies exploring epidemiological data, clinical outcomes, and long-term complications are needed to address the uncertainties in prevention and management.
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Affiliation(s)
- Luigi Cianni
- Dipartimento di Scienze dell'invecchiamento, Ortopediche e Reumatologiche, Unità Operativa Complessa di Ortopedia e Traumatologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
- Dipartimento di Sicurezza e Bioetica-Sezione di Malattie Infettive, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
| | - Francesco Taccari
- Dipartimento di Scienze Mediche e Chirurgiche, Unità Operativa Complessa di Malattie infettive, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| | - Maria Beatrice Bocchi
- Dipartimento di Scienze dell'invecchiamento, Ortopediche e Reumatologiche, Unità Operativa Complessa di Ortopedia e Traumatologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
- Dipartimento di Sicurezza e Bioetica-Sezione di Malattie Infettive, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
| | - Giulia Micheli
- Dipartimento di Sicurezza e Bioetica-Sezione di Malattie Infettive, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Dipartimento di Scienze Mediche e Chirurgiche, Unità Operativa Complessa di Malattie infettive, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| | - Flavio Sangiorgi
- Dipartimento di Sicurezza e Bioetica-Sezione di Malattie Infettive, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Dipartimento di Scienze Mediche e Chirurgiche, Unità Operativa Complessa di Malattie infettive, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| | - Antonio Ziranu
- Dipartimento di Sicurezza e Bioetica-Sezione di Malattie Infettive, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Ospedale Isola Tiberina-Gemelli Isola, 00186 Rome, Italy
| | - Massimo Fantoni
- Dipartimento di Sicurezza e Bioetica-Sezione di Malattie Infettive, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Dipartimento di Scienze Mediche e Chirurgiche, Unità Operativa Complessa di Malattie infettive, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| | - Giulio Maccauro
- Dipartimento di Scienze dell'invecchiamento, Ortopediche e Reumatologiche, Unità Operativa Complessa di Ortopedia e Traumatologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
- Dipartimento di Sicurezza e Bioetica-Sezione di Malattie Infettive, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
| | - Raffaele Vitiello
- Dipartimento di Scienze dell'invecchiamento, Ortopediche e Reumatologiche, Unità Operativa Complessa di Ortopedia e Traumatologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
- Dipartimento di Sicurezza e Bioetica-Sezione di Malattie Infettive, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
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Li Y, Zhang X, Ji B, Yushan N, Wulamu W, Guo X, Cao L. Conservative femoral revision using short cementless stems with a tapered rectangular shape for selected Paprosky II-IV bone defects: an average seven-year follow-up. ARTHROPLASTY 2024; 6:38. [PMID: 38907318 PMCID: PMC11191343 DOI: 10.1186/s42836-024-00251-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 03/18/2024] [Indexed: 06/23/2024] Open
Abstract
BACKGROUND The use of long stems for severe femoral bone defects is suggested by many scholars, but it is associated with further bone loss, intraoperative fracture, increased surgical trauma, and complications. With better bone retention, simple and quick surgical procedures, and minimal complications, the short cementless stems with a tapered rectangular shape may be an alternative for femoral revision. This study aimed to evaluate the results of this type of stem in treating selected Paprosky II-IV bone defects. METHODS This retrospective study included 73 patients (76 hips involved) who underwent conservative femoral revision using the short cementless stems with a tapered rectangular shape between January 2012 and December 2020. The preoperative femoral bone defects were identified as follows: 54 cases of type II, 11 cases of type IIIA, 7 cases of type IIIB, and 4 cases of type IV. Indications for revision included aseptic loosening (76.3%) and prosthetic joint infection (23.7%). Six cementless stems with a tapered rectangular shape from three companies were used in all patients. Among them, SLR-Plus, SL-Plus MIA, and Corail stems were employed in most patients (40.8%, 23.7%, and 17.1%, respectively). The average length of these stems measured 171.7 mm (SD 27 mm; 122-215 mm). Radiographic results, Harris hip scores (HHS), complications, and survivorship were analyzed. The follow-up lasted for 7 years on average (range 3-11 years). RESULTS The subsidence was observed in three hips (3.9%), and all stems achieved stable bone ingrowth. Proximal femoral bone restoration in the residual osteolytic area was found in 67 hips (88.2%), constant defects in nine hips (11.8%), and increasing defects in 0 cases. There was no evidence of stem fractures and stem loosening in this series. The mean HHS significantly improved from 32 (range 15-50) preoperatively to 82 (range 68-94) at the last follow-up (t = - 36.297, P < 0.001). Five hips developed prosthesis-related complications, including three infection and two dislocation cases. The mean 5- and 10-year revision-free survivorships for any revision or removal of an implant and reoperation for any reason were 94.6% and 93.3%, respectively. Both mean 5- and 10-year revision-free survivorships for aseptic femoral loosening were 100%. CONCLUSION Conservative femoral revision using short cementless stems with a tapered rectangular shape can provide favorable radiographic outcomes, joint function, and mid-term survivorship with minimal complications. Of note, a sclerotic proximal femoral bone shell with continued and intact structure and enough support strength is the indication for using these stems.
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Affiliation(s)
- Yicheng Li
- Department of Orthopaedics, First Affiliated Hospital of Xinjiang Medical University, 137 South Liyushan Road, Urumqi, Xinjiang, 830054, China
| | - Xiaogang Zhang
- Department of Orthopaedics, First Affiliated Hospital of Xinjiang Medical University, 137 South Liyushan Road, Urumqi, Xinjiang, 830054, China
| | - Baochao Ji
- Department of Orthopaedics, First Affiliated Hospital of Xinjiang Medical University, 137 South Liyushan Road, Urumqi, Xinjiang, 830054, China
| | - Nuerailijiang Yushan
- Department of Orthopaedics, First Affiliated Hospital of Xinjiang Medical University, 137 South Liyushan Road, Urumqi, Xinjiang, 830054, China
| | - Wuhuzi Wulamu
- Department of Orthopaedics, First Affiliated Hospital of Xinjiang Medical University, 137 South Liyushan Road, Urumqi, Xinjiang, 830054, China
| | - Xiaobin Guo
- Department of Orthopaedics, First Affiliated Hospital of Xinjiang Medical University, 137 South Liyushan Road, Urumqi, Xinjiang, 830054, China
| | - Li Cao
- Department of Orthopaedics, First Affiliated Hospital of Xinjiang Medical University, 137 South Liyushan Road, Urumqi, Xinjiang, 830054, China.
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Fiore M, Sambri A, Morante L, Bortoli M, Parisi SC, Panzavolta F, Alesi D, Neri E, Neri MP, Tedeschi S, Zamparini E, Cevolani L, Donati DM, Viale P, Campanacci DA, Zaffagnini S, De Paolis M. Silver-Coated Distal Femur Megaprosthesis in Chronic Infections with Severe Bone Loss: A Multicentre Case Series. J Clin Med 2023; 12:6679. [PMID: 37892817 PMCID: PMC10607434 DOI: 10.3390/jcm12206679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 10/20/2023] [Accepted: 10/20/2023] [Indexed: 10/29/2023] Open
Abstract
Periprosthetic joint infections (PJI) and fracture-related infections (FRI) of the distal femur (DF) may result in massive bone defects. Treatment options include articulated silver-coated (SC) megaprosthesis (MP) in the context of a two-stage protocol. However, there is limited evidence in the literature on this topic. A retrospective review of the prospectively maintained databases of three Institutions was performed. Forty-five patients were included. The mean follow-up time was 43 ± 17.1 months. Eight (17.8%) patients had a recurrent infection. The estimated recurrence-free survival rate was 91.1% (93.5% PJI vs. 85.7% FRI) 2 years following MP implantation, and 75.7% (83.2% PJI vs. 64.3% FRI; p = 0.253) after 5 years. No statistically relevant difference was found according to the initial diagnosis (PJI vs. FRI). Among possible risk factors, only resection length was found to significantly worsen the outcomes in terms of infection control (p = 0.031). A total of eight complications not related to infection were found after reimplantation, but only five of them required further surgery. Above-the-knee amputation was performed in two cases (4.4%), both for reinfection. Articulated DF SC MP in a two-stage protocol is a safe and effective treatment for chronic knee infection with severe bone loss.
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Affiliation(s)
- Michele Fiore
- Department of Medical and Surgical Sciences, Alma Mater Studiorum University of Bologna, 40138 Bologna, Italy; (M.F.); (S.T.)
| | - Andrea Sambri
- Orthopaedics and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (L.M.); (F.P.); (M.D.P.)
| | - Lorenzo Morante
- Orthopaedics and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (L.M.); (F.P.); (M.D.P.)
| | - Marta Bortoli
- Orthopaedics and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (L.M.); (F.P.); (M.D.P.)
| | - Stefania Claudia Parisi
- Orthopaedics and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (L.M.); (F.P.); (M.D.P.)
| | - Francesco Panzavolta
- Orthopaedics and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (L.M.); (F.P.); (M.D.P.)
| | - Domenico Alesi
- Second Orthopaedic Clinic, IRCCS Istituto Ortopedico Rizzoli, 40136 Bologna, Italy; (D.A.); (S.Z.)
| | - Elisabetta Neri
- Orthopaedic Oncology Unit, Azienda Ospedaliera Universitaria Careggi, 50134 Firenze, Italy (D.A.C.)
| | - Maria Pia Neri
- Second Orthopaedic Clinic, IRCCS Istituto Ortopedico Rizzoli, 40136 Bologna, Italy; (D.A.); (S.Z.)
| | - Sara Tedeschi
- Department of Medical and Surgical Sciences, Alma Mater Studiorum University of Bologna, 40138 Bologna, Italy; (M.F.); (S.T.)
- Infectious Disease Unit, Department for Integrated Infectious Risk Management, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Eleonora Zamparini
- Infectious Disease Unit, Department for Integrated Infectious Risk Management, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Luca Cevolani
- Third Orthopaedic Clinic, IRCCS Istituto Ortopedico Rizzoli, 40136 Bologna, Italy (D.M.D.)
| | - Davide Maria Donati
- Third Orthopaedic Clinic, IRCCS Istituto Ortopedico Rizzoli, 40136 Bologna, Italy (D.M.D.)
| | - Pierluigi Viale
- Department of Medical and Surgical Sciences, Alma Mater Studiorum University of Bologna, 40138 Bologna, Italy; (M.F.); (S.T.)
- Infectious Disease Unit, Department for Integrated Infectious Risk Management, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | | | - Stefano Zaffagnini
- Second Orthopaedic Clinic, IRCCS Istituto Ortopedico Rizzoli, 40136 Bologna, Italy; (D.A.); (S.Z.)
| | - Massimiliano De Paolis
- Orthopaedics and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (L.M.); (F.P.); (M.D.P.)
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Sambri A, Parisi SC, Zunarelli R, Di Prinzio L, Morante L, Lonardo G, Bortoli M, Montanari A, De Cristofaro R, Fiore M, De Paolis M. Megaprosthesis in Non-Oncologic Settings-A Systematic Review of the Literature. J Clin Med 2023; 12:4151. [PMID: 37373844 DOI: 10.3390/jcm12124151] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 05/31/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023] Open
Abstract
Modular megaprostheses (MPs) are commonly used after bone-tumor resection, but they can offer a limb salvage solution in massive bone defects. The aim of this systematic review of the Literature is to provide a comprehensive data collection concerning the use of MPs in non-oncologic cases, and to provide an overview of this topic, especially from an epidemiologic point of view. Three different databases (PubMed, Scopus, and Web of Science) were searched for relevant articles, and further references were obtained by cross-referencing. Sixty-nine studies met the inclusion criteria, reporting on cases of MP in non-oncologic cases. A total of 2598 MPs were retrieved. Among these, 1353 (52.1%) were distal femur MPs, 941 (36.2%) were proximal femur MPs, 29 (1.4%) were proximal tibia MPs and 259 (10.0%) were total femur MPs. Megaprostheses were most commonly used to treat periprosthetic fractures (1158 cases, 44.6%), in particular in the distal femur (859, 74.2%). Overall, complications were observed in 513 cases (19.7%). Type I (soft tissue failures) and type IV (infection) according to the Henderson classification were the most frequent (158 and 213, respectively). In conclusion, patients with severe post-traumatic deformities and/or significant bone loss who have had previous septic complications should be considered as oncologic patients, not because of the disease, but because of the limited therapeutic options available. The benefits of this treatment include relatively short operative times and immediate weight-bearing, thus making MP particularly attractive in the lower limb.
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Affiliation(s)
- Andrea Sambri
- Orthopedic and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Stefania Claudia Parisi
- Orthopedic and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Renato Zunarelli
- Orthopedic and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Lorenzo Di Prinzio
- Orthopedic and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Lorenzo Morante
- Orthopedic and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Gianluca Lonardo
- Orthopedic and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Marta Bortoli
- Orthopedic and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Andrea Montanari
- Orthopedic and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Roberto De Cristofaro
- Orthopedic and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Michele Fiore
- Orthopedic and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Massimiliano De Paolis
- Orthopedic and Traumatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
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Reimplantation after Periprosthetic Joint Infection: The Role of Microbiology. Antibiotics (Basel) 2022; 11:antibiotics11101408. [PMID: 36290065 PMCID: PMC9598703 DOI: 10.3390/antibiotics11101408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 10/11/2022] [Accepted: 10/11/2022] [Indexed: 11/26/2022] Open
Abstract
Periprosthetic joint infection (PJI) is among the most feared orthopedic complications. Critical questions are whether the infection is completely resolved before reimplantation and what the clinical significance of positive culture is at reimplantation. The aim of this study was to determine whether a correlation exits between culture results at reimplantation after spacer insertion for hip and knee PJI and treatment failure rate. The data of 84 patients who underwent two-stage exchange arthroplasty for hip or knee PJI were reviewed and the results of intraoperative culture at reimplantation were analyzed quantitatively and qualitatively. Correlations were sought between these patterns and treatment outcome. Our data indicate no evidence for a correlation between positive culture at reimplantation and greater risk of treatment failure. Nonetheless, we noted a higher, albeit statistically not significant rate of treatment failure in patients with at least two samples testing positive. The role of microbiology at reimplantation remains unclear, but a positive culture might signal increased risk for subsequent implant failure. Further studies are needed to elucidate the implications of this finding.
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