1
|
Thalmann C, Kempter P, Stoffel K, Ziswiler T, Frigg A. Prospective 5-year study with 96 short curved Fitmore™ hip stems shows a high incidence of cortical hypertrophy with no clinical relevance. J Orthop Surg Res 2019; 14:156. [PMID: 31133027 PMCID: PMC6537407 DOI: 10.1186/s13018-019-1174-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 04/29/2019] [Indexed: 12/20/2022] Open
Abstract
Background An increased occurrence of cortical hypertrophy (CH) was observed 1–2 years after implanting short curved Fitmore hip stems. There are no published data about either the clinical relevance or the progression of CH over the long term. Methods Ninety-six primary total hip arthroplasties were performed between 2008 and 2010 using the Fitmore hip stem. Clinical and radiological parameters were recorded preoperatively and at 1, 2, 3, and 5 year follow-up. Results CH appeared mainly on antero-posterior radiographs in Gruen Zones 2, 3, 5, and 6. After 1 year, the diameter was 10 ± 2 mm and remained constant thereafter. The CH rate after 1 year was 69% and after 5 years 71%. Subsidence after 1 year was 1.6 ± 1.55 mm and 1.93 ± 1.72 mm after 5 years. Cortical thinning was 46% after 1 year and 56% after 5 years, mainly in Gruen Zones 7 and 8. In the first year radiolucencies were found in 51% in all Gruen Zones, and in 20% after 5 years. Patient, implant, and surgical factors did not correlate with radiological outcomes except that larger stems had more CH. After 5 years, the Harris Hip Score had improved from 59 to 94 and the Oxford Hip Score from 22 to 41. Radiographic parameters, notably CH, were not associated with clinical outcomes except that cortical thinning correlated with lower outcome scores. Conclusions CH correlated neither with clinical outcome nor with patient, surgical or implant factors, except for a positive correlation with stem size. The Fitmore hip stems settled within the first year to a stable fixation and then remained almost unchanged. However, cortical thinning is common in Gruen Zone 7 and 8 meaning that there is stress-shielding.
Collapse
Affiliation(s)
- Caroline Thalmann
- Orthopedic Department, Kantonsspital Graubünden, Loestrasse 99, 7000, Chur, Switzerland.,Orthopedic Department, University Hospital Basel, Spitalstrasse 21, 4031, Basel, Switzerland
| | - Patricia Kempter
- Orthopedic Department, Kantonsspital Graubünden, Loestrasse 99, 7000, Chur, Switzerland.,Orthopedic Department, University Hospital Basel, Spitalstrasse 21, 4031, Basel, Switzerland
| | - Karl Stoffel
- Orthopedic Department, Kantonsspital Graubünden, Loestrasse 99, 7000, Chur, Switzerland.,Orthopedic Department, University Hospital Basel, Spitalstrasse 21, 4031, Basel, Switzerland.,Orthopedic Department, Kantonsspital Liestal, Rheinstrasse 26, 4410, Liestal, Switzerland
| | - Thea Ziswiler
- Orthopedic Department, Kantonsspital Graubünden, Loestrasse 99, 7000, Chur, Switzerland.,Orthopedic Department, University Hospital Basel, Spitalstrasse 21, 4031, Basel, Switzerland
| | - Arno Frigg
- Orthopedic Department, Kantonsspital Graubünden, Loestrasse 99, 7000, Chur, Switzerland. .,Orthopedic Department, University Hospital Basel, Spitalstrasse 21, 4031, Basel, Switzerland. .,Private University of the Principality of Liechtenstein, Triesen, Liechtenstein.
| |
Collapse
|
2
|
Schuh A, Schraml A, Hohenberger G. Long-term results of the Wagner cone prosthesis. INTERNATIONAL ORTHOPAEDICS 2007; 33:53-8. [PMID: 17932669 DOI: 10.1007/s00264-007-0460-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2007] [Revised: 07/04/2007] [Accepted: 08/03/2007] [Indexed: 11/30/2022]
Abstract
The Wagner cone prosthesis is indicated in uncemented total hip replacement of cases with cylinder-shaped femurs, deformed femurs, femurs with increased antetorsion, and in conditions of intramedullary bony scar tissue after previous osteotomies. The objective of this study is to present long-term results. From January 1, 1993 to December 31, 1995, 132 implantations were made with the Wagner cone prosthesis. We report the clinical and radiographic results of 94 cone prostheses with a mean observation period of 11.5 years. The Merle d'Aubigné score improved from a preoperative mean value of 8.8 to a postoperative mean of 16.3. The radiographic evaluation revealed 32 cases with cortical hypertrophy, 73 cases with atrophy of the proximal femur, and 18 cases with complete pedestal formation. Radiolucencies over Gruen zones 1 and 7 occurred in 42 cases; only zone 1 was affected in 24 cases. Complications included three deep infections, three acetabular revisions, five total joint revisions, one recurrent luxation, and three heterotopic ossifications. In spite of the fact that the examined cohort often included patients who had undergone multiple previous operations (a maximum of six) of the proximal femur or the acetabulum, the long-term results of the Wagner cone prostheses were very promising.
Collapse
Affiliation(s)
- Alexander Schuh
- Research Unit Orthopaedics and Surgery, Neumarkt Hospital, Teaching Hospital of the University of Erlangen-Nuremberg, Nürnbergerstrasse 12, 92318, Neumarkt i.d. OPf, Germany.
| | | | | |
Collapse
|