Centre of excellence of joint replacements

Transcription

1 REPORT 2008 Centre of excellence of joint replacements The Norwegian Arthroplasty Register The Norwegian Cruciate Ligament Register The Norwegian Hip Fracture Register Helse-Bergen HF, Department of Orthopaedic Surgery Haukeland University Hospital Report in Norwegian: ISBN: ISSN:

2 Report 2008

3 Contents Preface The Norwegian Arthroplasty Register Hip prostheses Number of total hip replacements by year of operation... 1 Incidence of primary total hip replacements by gender and age (1995, 2000, 2005)... 1 Hip disease... 2 Patient age by year of operation... 2 Reason for revision... 3 Type of revision... 4 Bone transplant... 5 Operative approach... 6 Trochanteric osteotomy... 6 Systemic antibiotic prophylaxis... 6 Cement... 7 Cement and bone transplant in revisions... 8 Cement brands Common combinations of prosthesis brands (acetabulum and femur) Prosthesis brands, acetabulum Prosthesis brands, femur Monoblock and modular caput Caput diameter in modular prostheses Prosthesis brands, modular caput ASA classification Thrombosis prophylaxis Mini-invasive surgery Computernavigation Bone loss at revision Articulation, primary operations Kaplan-Meier survival curves by year of operation and use of cement Knee prostheses Number of knee replacements by year of operation Incidence of primary knee replacements by gender and age (1995, 2000) Number of knee replacements by year of operation and type of prosthesis Knee disease Cement Prosthesis brands Reason for revision Patient age by year of operation Type of revision Kaplan-Meier survival curves by year of operation and type of prosthesis Elbow prostheses Number of elbow replacements by year of operation Elbow disease Cement Prosthesis brands Reason for revision... 57

4 Report 2008 Ankle prostheses Number of ankle replacements by year of operation Ankle disease Cement Prosthesis brands Reason for revision Finger joint prostheses (MCP, PIP) Number of finger joint replacements by year of operation Finger joint disease Cement Prosthesis brands Reason for revision Wrist prostheses Number of wrist replacements by year of operation Wrist disease Cement Prosthesis brands Reason for revision Carpometacarpal prostheses (CMC I) Number of CMC I replacements by year of operation CMC I disease Cement Prosthesis brands Reason for revision Lumbar disc prostheses Number of lumbar disc replacements by year of operation Lumbar disc disease Cement Prosthesis brands Shoulder prostheses (total, hemi) Number of shoulder replacements by year of operation Shoulder disease Cement Prosthesis brands Reason for revision Toe joint prostheses Number of toe joint replacements by year of operation Toe joint disease Cement Prosthesis brands Reason for revision Kaplan-Meier survival curves for elbow, ankle, finger, CMC I, shoulder and toe... 86

5 The Norwegian Hip Fracture Register Introduction Number of hip fractures by year of operation Incidence of primary hip fracture Age by primary operation Time from fracture to operation primary operation Cognitive impairment primary operation Type of anaesthesia primary operation ASA classification Type of fracture reason for primary operation Reason for reoperation Reason for reoperation by reason for primary fracture Type of primary operation vs. reason for primary operation Type of primary operation all fractures Type of reoperation Type of reoperation after primary uni/bipolar hemiprosthesis Type of reoperation after primary screw fixation Hemiprosthesis primary operation Hemiprosthesis reoperation Screws primary operation Hip compression screw primary operation Nail primary operation Fixation of primary hemiprosthesis Cement with antibiotics primary operation Fixation of primary hemiprosthesis uncemented Pathological fracture primary operation Operative approach when primary hemiprosthesis Peroperative complications primary operation Systemic antibiotic prophylaxis Thrombosis prophylaxis Kaplan-Meier survival curves for hip fractures The Norwegian Cruciate Ligament Register Introduction All operations Number of procedures by year of operation Incidence of primary reconstruction of crucate ligament The number of other procedures for all categories of surgeries Distribution of other procedures in combination with primary reconstruction of cruciate ligament Distribution of other procedures in combination with reconstruction Distribution of other procedures when this is the only procedure Per operative complications Primary reconstruction of cruciate ligament

6 Report 2008 Age at primary operation Activity that lead to injury Injury ACL with additional injuries PCL with additional injuries Choice of graft Fixation femur ACL Fixation femur PCL Fixation tibia ACL Fixation tibia PCL Fixation femur and tibia ACL Meniscal lesion Fixation Meniscal lesion Cartilage lesion: ICRS grade Cartilage lesion: probable cause Cartilage lesion: treatment Cartilage injuries Outpatient surgery Per operative complications Systemic antibiotic prophylaxis Thrombosis prophylaxis Revision reconstruction Age at primary operation Activity that lead to injury Injury ACL with additional injuries PCL with additional injuries Choice of graft Fixation femur ACL Fixation femur PCL Fixation tibia ACL Fixation tibia PCL Fixation femur and tibia ACL Meniscal lesion Fixation Meniscal lesion Cartilage lesion: ICRS grade Cartilage lesion: probable cause Cartilage lesion: treatment Cartilage injuries Outpatient surgery Per operative complications Systemic antibiotic prophylaxis Thrombosis prophylaxis Other procedures Age at primary operation Activity that lead to injury Injury ACL with additional injuries PCL with additional injuries Meniscal lesion Fixation Meniscal lesion Cartilage lesion: ICRS grade

7 Cartilage lesion: probable cause Cartilage lesion: treatment Cartilage injuries Outpatient surgery Per operative complications Systemic antibiotic prophylaxis Thrombosis prophylaxis Kaplan-Meier survival curves for cruciate ligament Publications...173

8 Report 2008

9 ANNUAL REPORT 2008 The Norwegian Arthroplasty Register performs quality control and research on all joint replacements from all hospitals in Norway. From the period the register contains information about hip prosthesis operations. In January 1994 the register expanded to include also replacements in other joints. From the period it is registered data on knee replacements and in other joints than hip or knee. June 7 th 2004 the registering of operations on the cruciate ligament started. From the start and until December 31 st 2007 it is registered cruciate ligament operations. For more information please refer to the preface for the National Cruciate Ligament Register on page 115. The Norwegian Hip Fracture Register was started January 1 st 2005 and there are primary hip fractures and revisions registered so far. For more information please refer to the preface on page 87. We have decided to publish mainly descriptive statistics in the annual reports. Comparative studies, for instance of the quality of different types of prostheses, are presented in scientific lectures, posters or papers. We strongly feel that the results from comparing types of prostheses should include a thoroughly review on how the patients in the study were picked and the use of statistical methods. It should also include a discussion on how the results should be interpreted. This is best done in a scientific setting, and we refer to our list of references in the end of this report and on our web-page ( The web-page also includes an English version of the annual report for Most of our reports and papers can be read directly from this web-page (some magazines will not give their permission). We give here an overview of the last year s scientific findings with references to the papers and abstracts, and we encourage the readers to look at our web-page and study the papers. ANNUAL REPORTS TO THE HOSPITALS The annual reports to each hospital where sent to the contact persons at the respective hospitals in September The reports include data for We encourage the orthopedic divisions to use the annual report actively in their quality work. This year a PDF-type file will be sent to the contact person to make presentations to their colleagues easier. PhDs in 2007 Orthopedic surgeon Geir Hallan at the Department of Orthopedic Surgery, Haukeland University Hospital defended his medical PhD Wear, fixation and revision of total hip prostheses January 19 th 2007 (PhDs 6). This is reported thoroughly in last year s annual report. Karin Monstad at Norwegian school of economics and business administration (NHH) defended her PhD Essays on the Economics of health and fertility (7) September 28 th The main discovery was that the hip replacement patients to a small extent took advantage of their right to choose hospital in order to shorten the waiting time to the replacement. She showed further that the elder patients were more reluctant to travel than the younger ones, but the characteristic that counted most was their level of education, patients with education more than high school were more willing to travel than the rest. PROSTHESIS SURGERY IN NORWAY 2007 It was a 5 % increase in the number of primary hip replacements from 2006 to 2007, and a 15 % increase in primary knee replacements (Table 1). It is still cemented prostheses (both components) which dominate as the fixation method both for hip and knee (Figure 5-7). Conventional polyethylene is the most common used as articulation, but the use of cross

10 Report 2008 linked polyethylene is increasing. This new type of plastic was used in 839 primary hip prostheses in 2007 (Table 41-43). The use of uncemented stems and cemented cups in the younger patients is promising and has increased. Randomized studies are on their way and we will encourage the surgeons to wait for the results from these. We will advise against the use of uncemented cups with conventional polyethylene (Abstract 27). The number of revisions in the hip has increased somewhat from 12.3 % in 2003 to 13.6 % in 2007 (Table 1). Preliminary analyses show that the users of the Charnley prosthesis have improved their results the last 10 years, but there is little improvement for the other cemented prostheses. This shows that there is room for improvement and that there must be a focus on surgical techniques in the education of surgeons (Abstract 6). Dislocation, infection, wear, osteolysis, and acetabular loosening are still frequent reasons for revisions, and these problems have to be solved through development of technology, research and not the leas better surgical techniques. NEW TABLES AND FIGURES The figures and tables have each a number to make it easier to find and read. We have included tromboprophylaxis and ASA class for knee prostheses (Table 22-29). We have promised the steering committee to analyze the tromboprophylaxis data so they soon can be removed from the form, because these questions take a long time to complete. It has been a trend that it is more common to give the first dose after the operation. This way of doing it is supported by randomized studies with surrogate endpoint (venografical shown deep venous thrombosis). We will study if this practice also is advisable if the death of the patient is the endpoint. SUMMARY OF THE MOST IMPORTANT FINDINGS IN 2007 Two PhDs and 10 papers are published in scientific journals. Until now in papers have been published, 4 papers are approved for publication and 4 are submitted for publication. 18 chapters in books are written. Uncemented femoral stems have good results. Corail (HA covered) is the one most used and has the fewest revisions with endpoint all stem revisions. The difference is small between the uncemented femoral stems used today regarding aseptic loosening as a reason for revision, with % survival after 10 to 15 years of follow up. The problem is that the long term result for the total prosthesis is not so good due to many revisions at the cup side due to wear and loosening of uncemented cups (Dissertation 6, 53). In a study with Zweymuller SL uncemented press-fit stem and Endler Titanium screw cup with fixed polyethylene (n=70) from two hospitals there was however good results for young patients (24-68 years) with 16 years median follow up (55). Revisions of fixed uncemented cups with isolated acetabular liner exchange gave two times higher risk for revision compared with complete acetabular component revision. This indicates that the threshold to remove a fixed acetabular component can be lowered (48). The results for conversion from failed hemiarthroplasties to total hip artrhoplasties are best when the whole prosthesis were exchanged, to operate in a new acetabular component and keep the old femoral stem gave a higher risk of revision, especially due to dislocation (51). The results for total hip prosthesis after acute femoral neck fractures and sequela after fracture of femoral neck are in general good, but not as good as for primary osteoarthritis. This was due to an increase in dislocation and an increase in periprostetic fractures and infections. The risk of revision was especially higher the first six months after the primary operation compared to primary osteoarthritis patients (63).

11 Unicompartmental knee arthroplasties had twice the revision risk compared to total knee arthroplasties in all age groups. This was due to increased aseptic loosening of both femoral and tibia components and increased revision for periprostetic fractures (45). There was a reduction in incidence of orthopedic surgery among patients with chronic inflammatory joint diseases in the time period 1994 to 2004; this was probably due to better medication. The incidence of orthopedic surgery for primary osteoarthritis has increased in the same time period (46). The results for ankle arthroplasties were inferior after 10 years compared to arthroplasties of other joints. It has not improved the last 10 years. LINK STAR ankle arthroplasty with HA porous coating has less aseptic loosening than with HA on a smooth surface (50). Men had a higher risk of loosening of the femoral stem than women, and men and women with a high body weight had a higher risk of loosening of the femoral stem. Men with high physical activity in their leisure time had a higher risk for loosening of the cup (47). In a comparative study between the Swedish and the Norwegian Arthroplasty Registers and the Medicare database in the US it was shown that the 8 year survival for hip prostheses in the age group above 65 years was better both in Sweden and Norway than in the US. For knee prostheses the results were better in the US than in Norway. Because there was no data on prosthesis components in the Medicare database we could not analyze the reasons for these results. Our hypothesis was that good results for the hip prostheses in Sweden and Norway were due to a high rate of cemented prostheses, and the good results of the knee prostheses in the US were due to a higher rate of patella resurfacing (49). For the Charnley prostheses the lateral approach with trochanteric osteotomy reduced the risk for revision compared to lateral approach without osteotomy due to dislocation, and in the time period also less revisions due to aseptic loosening. There were more revisions due to dislocation with the use of posterolateral approach (52). The result for hip prosthesis after a developmental dysplasia of the hip was as good as after a primary osteoarthritis, when we adjust for age and the use of uncemented prostheses (54). ONGOING PhD RESEARCH WITHIN JOINT PROSTHESES AND HIP FRACTURES Hilde Apold (doctor in specialization) at Orthopedic Center, Ullevål University Hospital, investigates data from the Norwegian Institute of Public Health and the Norwegian Arthroplasty Register. Astvaldur Arthursson (orthopedic surgeon) at Stavanger University Hospital has a PhD grant from Helse Vest RHF to study the results of different surgical approaches for total hip arthroplasty (52), and to validate the data from Stavanger University Hospital compared to the Norwegian Register and the Norwegian Patient Register (38). He defended his thesis 13 th of November.. Stein Hakon Lygre (MSc and statistician) has a PhD grant from Health and Rehabilitation to study data on function, pain and quality of life after primary and revision arthroplasties in the knee. He has sent out a questionnaire on quality of life (EQ-5D), function and pain (KOOS) to selected patients. He now studies the differences between primary total prostheses in knees

12 Report 2008 with or without patella component (Abstract 29). He found no difference in pain and function between knee prostheses with or without patella component. Eva Dybvik (MSc and statistician) has a PhD grant from Helse Vest RHF to study cancer treatment and result of hip prostheses. Data from the Cancer Registry in Norway and the Norwegian Arthroplasty Register are coupled. Bjørg Tilde Fevang (post doc) has published a paper on ankle arthroplasties (50) and a paper on shoulder arthroplasties in Norway have been accepted for publication. She is currently working on a paper on elbow arthroplasties and a paper on improvement of the prostheses surgery in Norway. Ingvild Engesæter (stud med) and Trude Lehmann (cand med) study the results of hip arthroplasty surgery for children hip diseases. Ingvild has a paper on risk of total hip replacement in younger adulthood after neonatal hip instability accepted for publication in Acta Orthopaedica (56). She works in addition with the validation of the diagnosis in children hip diseases and with functional analyzes of prostheses after children hip diseases. Jan-Erik Gjertsen (doctor in specialization) studies the result of total hip replacement in patients with hip fractures (63). He describes the start of the Hip Fracture Register (62, 65 Abstract 46, 48), and the functional results after osteosynthesis or hemi prosthesis with displaced intracapsular fractures (Abstract 49). We hope he will deliver his PhD thesis within the turn of the year. Kjell Matre (orthopedic surgeon) studies mortality after trochanteric and subtrochanteric fractures (Abstract 50, 53). Tarjei Vinje (doctor in specialization) studies mortality after dislocated intracapsular femoral neck fractures (Abstract 47). Håvard Dale (orthopedic surgeon), Jan Schrama (orthopedic surgeon) and Håkon Langvatn (stud med) study the development of infections after hip prostheses related to antibiotic prophylaxis (Abstract 30). Håkon Langvatn has traveled to selected hospitals in Norway to study the microbiological test answers after revised infected hip prostheses. ACADEMIC TEACHING BOOK IN IMPLANT SURGERY Coworkers at the Register have participated in writing a teaching book for candidates who is specializing in orthopedic surgery in hip and knee and orthopedic infections. The book is especially adjusted to the curriculum at the compulsory course regarding this subject held at Røros each year. The book is hardback and with many new color illustrations and will be a valuable reference book for all orthopedic surgeons and all orthopedic departments. The editors have been Arild Aamodt, Greger Lønne and Ove Furnes. The book can be ordered at JOINT PROJECTS Stein Atle Lie is leading a study on total hip and knee replacement and postoperative mortality comparing data from the Australian and Norwegian Arthroplasty Registers (Abstract 10). The paper has been submitted for publication.

13 The Norwegian Arthorplasty Register cooperates with the Norwegian Institute of Public Health and Orthopedic Center at Ullevål University Hospital in several studies on the risk of receiving a hip or knee prosthesis. We have started a joint project with Dartmouth University in New Hampshire, US, where we use decision theory (cost-effectiveness analysis). The first study on unicompartmental or total knee arthroplasty in elderly patients is published (44), and two more studies are in progress, one regarding computer navigation in knee arthroplasty and the other on the use of antibiotics in cement. The Register is part of the Locus for registry-based epidemiology at the University of Bergen and we have used data from the Medical Birth Register. A paper has been published (56). The Register has participated at the meeting in International Society of Arthroplasty Registers (ISAR) under AAOS in San Francisco Leif Ivar Havelin is a member of the board. The goal for the society is to be a forum for national and greater regional registers where they can inform about results, experiences and also work on standardizing the reporting and registration. A symposium was held on register research at the latest AAOS, where Leif Ivar Havelin presented data on unicompartmental and total knee prostheses from the Norwegian Register (Abstract 21). Kerstin Pankewitsch, the University of Halle, Germany, is working on a PhD project where she performs data mining on data from the Register. She presented some of the results on the EAR (European Arthroplasty Register) symposium at the EFFORT meeting in Florence in NORDIC ARTHROPLASTY REGISTER ASSOCIATION (NARA) The Norwegian, Swedish and Danish Hip Arthroplasty Registers have now completed the coupling of data in an analysis file. Several papers are planned. The first study is headed by Leif Ivar Havelin and the paper has been submitted for publication. We expect a lot from this cooperation, where the focus will be on prostheses and techniques where the data samples are too small in each country on its own. MEETING WITH THE ORTHOPEDIC SOCIETY OF NORTHERN NORWAY Leif Ivar Havelin and Lasse Engesæter were in Tromsø in November. The meeting got a good review, and they showed results for the hospitals and discussed the differences between the four Health Divisions in Norway. Next year we plan a meeting in mid Norway (Helse Midt- Norge). COOPERATION WITH SINGLE HOSPITALS Coworkers at the Register receive many inquiries from single hospitals and doctors and we try to help out as much as we have capacity to. All together we had 32 relatively large summonses of data and analyzes done for hospitals, doctors, institutions, industry and the government in REPORTING REVISIONS When there are infections or removal of prostheses (in the hips as a Girdlestone operation) or part of he prosthesis has to be removed; it should be reported on the standard register form where one state the reason for the operation and which parts that have been removed. One also has to report when a new prosthesis has been operated in to a joint which has previously had a prosthesis removed.

14 Report 2008 EXCHANGE OF PLASTIC PARTS These revisions shall, as other revisions, be reported on the standard form where you mark out the reason for revision and what has been done, if necessary one can write this in free text. In our survival analysis we will differentiate between different types of revisions and state the endpoint in the analysis. Most commonly we will use all types of revisions of the femur and acetabulum component as the endpoint, or we can perform analysis where we exclude exchange of plastic parts in the endpoint definition. Generally we give the total number of revisions in addition to the number of revisions with only exchange of plastic parts. ADMINISTRATIVE CONDITIONS The Norwegian Register of Arthroplasty is declared as national center of excellence of joint replacements. All the functions of the center (The Norwegian Arthroplasty Register, The Norwegian Hip Fracture Register and The National Cruciate Ligament Register) are located at Møllendalsbakken 11 (close to Haukeland University Hospital). We receive funding from Helse Vest RHF and from Helse Bergen, and for The National Cruciate Ligament register also from Oslo Sports Trauma Research Center (Helse Sør-Øst). 20 YEAR ANNIVERSARY IN BERGEN SEPTEMBER 26 TH AND 27 TH 2007 The anniversary was held at Hotel Norge in Bergen. It was 120 participations on the two day long scientific symposium where we gave an overview of results and new findings from the register. It was five main topics; the use of data from medical quality registers with an introduction from the owners of the hospitals, hip arthroplasty surgery, knee arthroplasty surgery (including ankle and shoulder arthroplasty surgery), cruciate ligament surgery and hip fracture surgery. We arranged a symposium dinner at Maartmannshaven at Hotel Norge. The symposium got one-page coverage in Aftenposten. We give a big thank you to all the participants and contributors. SYMPOSIUM AT THE AUTUMN MEETING The registers arranged a two hour anniversary symposium at the annual orthopedic meeting. We presented and discussed the most important findings the last years with subjects from hip arthroplasty surgery with focus on new articulations, arthroplasty surgery in knee and other joints, cruciate ligament surgery and hip fracture surgery. This year s symposium will discuss the problems around making the hospital results public and how to handle possible divergence. STAFF Orthopedic surgeon and professor Ove Furnes is head of the Arthroplasty Register. Coworkers are orthopedic surgeon and Professor Lars Birger Engesæter, orthopedic surgeon and Professor Leif Ivar Havelin and orthopedic surgeon Geir Hallan. Together these four share one position at the register. Leif Ivar Havelin is in charge of the hip arthrolpasty, Ove Furnes is in charge of the knee and other joints arthroplasty, and Lars Birger Engesæter is in charge of the hip fracture register. The surgeons Jan-Erik Gjertsen, Tarjei Vinje, Kjell Matre, and Jonas Fevang (supervisor) are all doing research on data from the hip fracture register. Birgitte Espehaug and Anne Marie Fenstad (50 % position from August 1 st 2007) are statisticians. Kjersti Steindal is a computer engineer and has an extra responsibility for annual reports from the cruciate ligament and hip fracture registers and our databases. Tor-Egil Sørås is a computer engineer (40 % position) and works with the databases for the arthroplasty registers and the annual reports of these. Stein Atle Lie has a 20 % position as a statistician and advisor. Director of the Medical Birth Register, professor Stein Emil Vollset is scientific

15 and statistic advisor. Secretaries are Inger Skar (knee and other joints), Ingun Vindenes (hip prostheses), Ruth Wasmuth (cruciate ligament), Marianne Wiese (hip fracture), and Kari Alvær (hip fracture). Surgeon Knut Fjeldsgaard is scientific contact for the cruciate ligament register together with head of the board Lars Engebretsen and medical student Lars P. Granan. Randi Hole is performing research on data from the cruciate ligament register. Lise Kvamsdal is project coordinator with main responsibility for the hip fracture register. APPRECIATION TO INGER SKAR Inger has worked as a secretary at the register in more than 10 years. She has been responsible for the registration of the forms for knee and other joints. She will now retire after all together 22 years at Haukeland University Hospital. She has done an excellent job for the register with her accurate registration, her thoroughly follow up to new prostheses and her great skills to look after the boss. We will miss her at the register. We will thank her and wish her good luck with her retirement. BOARD OF THE NORWEGIAN ARTHROPLASTY REGISTER The Norwegian Orthopedic Association is the owner of the register and the general meeting in the Norwegian Orthopedic Association is its highest organ. The Norwegian Orthopedic Association has appointed a board consisting of leader professor Lars B. Engesæter (University of Bergen), Professor Lars Nordsletten (Helse Øst), Professor Arild Aamodt (Helse Midt Norge), orthopedic surgeon Odd Inge Solem (Helse Nord), and orthopedic surgeon Svein Svenningsen (Helse Sør), Professor Leif Ivar Havelin (Helse Vest) and head of the register Professor Ove Furnes. Professor emeritus Einar Sudmann is an honorary member of the board and professor Lars Engebretsen at Orthopedic Center, Ullevål University Hospital meets as the head of the board for the cruciate ligament register. BOARD OF THE CRUCIATE LIGAMENT REGISTER The board of the cruciate ligament register consists of the head professor Lars Engebretsen, surgeon Knut Fjeldsgaard, Surgeon Jon Olav Drogseth, Chief surgeon Arne Ekeland, Professor Roald Bahr and Professor Ingar Holme. ACKNOWLEDGEMENT The Norwegian Arthroplasty Register/Centre of excellence of joint replacements would like to thank all orthopedic surgeons in the country for excellent reporting. Further we would like to thank Helse Bergen, Helse Vest, all product distributors, Locus for registry based epidemiology, University of Bergen, Oslo Sports Trauma Center at the Norwegian University of Sport and Physical Education, Norwegian Patient Register, The Norwegian Institute of Public Health, Norwegian Board of Health Supervision, and the Norwegian Health Authorities, for the good cooperation in Bergen,

16 Report 2008

17 Hip prostheses Table 1: Annual number of operations Year Figure 1: Annual number of operations Primary operations Revisions (86,4%) (13,6%) (86,2%) (13,8%) (86,2%) (13,8%) (86,9%) 939 (13,1%) (87,7%) 990 (12,3%) (86,6%) 956 (13,4%) (87,0%) 922 (13,0%) (85,4%) 975 (14,6%) (85,3%) 943 (14,7%) (83,5%) (16,5%) (84,0%) (16,0%) (82,8%) (17,2%) (83,8%) 985 (16,2%) (83,5%) 910 (16,5%) (85,1%) 845 (14,9%) (86,4%) 769 (13,6%) (85,2%) 783 (14,8%) (86,9%) 732 (13,1%) (87,5%) 741 (12,5%) (85,8%) 651 (14,2%) (88,0%) 179 (12,0%) Registration complete from 1989 The Norwegian Arthroplasty Register (85,7%) (14,3%) Number of operations Primary operations Revisions 55,2% of the operations were performed on the right side. 68,7% of the operations were performed on women. Mean age was 69,5 years. Figure 2: Incidence of primary hip prostheses Number of operations per inhabitants Women 2000 Women 2005 Women 1995 Men 2000 Men 2005 Men 0 Age: < > 79

18 Report 2008 Hip disease Table 2: Hip disease Year Primary osteoarthritis Rheumatoid arthritis Fract. of femoral neck Congenital dysplasia Diseases are not mutually exclusive Congenital dislocation Epiphysiol./Pert hes' disease Ankylosing spondylitis Acute fract. of the femur Other Missing information Figure 3: Age by year of operation 50 Proportion (%) of primary operations Year of operation <45 years years years years >79 years 2 Hip

19 The Norwegian Arthroplasty Register Reasons for revision Table 3: Reasons for revision Year of revision Acetabular loosening Femoral loosening Dislocation Deep infection Revision causes are not mutually exclusive Fracture of femur Pain Osteolysis acet., no loosening Osteolysis femur, no loosening Polyethylene wear Previous Girdlestone Other Missing information Figure 4: Reasons for revision 1600 Reasons for revision Miss ing information Other Osteolysis and wear Pain Fracture of femur Deep infection Dislocation 200 Femoral loosening Acetabular loosening Year of revision Hip 3

20 Report 2008 Type of revision Table 4: Type of revision Year of revision Exchange, acetabulum Exchange, caput Exchange, caput and acetab. Exchange, femur Exchange, all components Exchange, PE liner Exchange, PE liner and caput Exchange, PE liner and femur Removal, femur Girdlestone Previous Girdlestone Other Missing information 13% 6% 27% 13% 26% 0% 4% 1% 0% 5% 1% 3% 0% % 3% 21% 14% 26% 1% 6% 1% 0% 6% 2% 1% 0% % 3% 16% 13% 30% 1% 4% 2% 0% 5% 2% 3% 1% % 4% 20% 14% 29% 1% 5% 2% 0% 7% 2% 1% 1% % 3% 13% 17% 28% 1% 5% 2% 0% 6% 2% 1% 1% % 2% 15% 19% 31% 1% 6% 2% 1% 5% 3% 2% 1% % 2% 19% 21% 31% 1% 5% 2% 5% 3% 1% 0% % 2% 20% 21% 31% 1% 7% 1% 0% 4% 3% 0% 0% % 2% 14% 21% 37% 0% 5% 1% 0% 5% 3% 1% 0% % 1% 16% 20% 37% 1% 4% 2% 0% 4% 4% 1% % 1% 11% 22% 40% 1% 3% 1% 0% 4% 4% 0% 0% % 1% 11% 23% 42% 0% 1% 0% 0% 6% 3% 1% 0% % 1% 9% 24% 42% 0% 1% 0% 0% 4% 4% 1% % 0% 2% 28% 44% 0% 1% 0% 1% 4% 2% 1% % 0% 1% 28% 45% 0% 0% 0% 4% 1% 0% 0% % 1% 1% 26% 49% 0% 0% 0% 0% 5% 1% 1% 0% % 0% 0% 25% 49% 0% 1% 5% 0% 1% 1% % 1% 25% 55% 0% 0% 3% 0% 0% 2% % 0% 0% 24% 58% 0% 2% 0% 0% 1% % 1% 20% 63% 0% 0% 2% 2% 0% 1% % 1% 21% 63% 1% 1% 1% % 2% 12% 21% 39% 0% 3% 1% 0% 5% 2% 1% 1% 4 Hip

21 The Norwegian Arthroplasty Register Bone transplant Table 5: Bone transplant acetabulum - Revisions Year of revision Yes No Bone impaction Missing (12,7 %) 586 (56,2 %) 192 (18,4 %) 133 (12,8 %) (11,4 %) 554 (54,9 %) 201 (19,9 %) 139 (13,8 %) (15,2 %) 527 (49,8 %) 230 (21,7 %) 141 (13,3 %) (17 %) 570 (60,7 %) 162 (17,3 %) 47 (5 %) (16,4 %) 651 (65,8 %) 147 (14,8 %) 30 (3 %) (22,1 %) 621 (65 %) 86 (9 %) 38 (4 %) (19,7 %) 578 (62,7 %) 132 (14,3 %) 30 (3,3 %) (22,2 %) 601 (61,6 %) 136 (13,9 %) 22 (2,3 %) (20,3 %) 593 (62,9 %) 141 (15 %) 18 (1,9 %) (21,5 %) 642 (61,1 %) 160 (15,2 %) 22 (2,1 %) (21,6 %) 636 (62,9 %) 134 (13,3 %) 23 (2,3 %) (25,2 %) 639 (63,6 %) 82 (8,2 %) 30 (3 %) (31,8 %) 641 (65,1 %) 4 (0,4 %) 27 (2,7 %) (31,6 %) 607 (66,7 %) 0 (0 %) 15 (1,6 %) (31,4 %) 558 (66 %) 0 (0 %) 22 (2,6 %) (26,9 %) 541 (70,4 %) 0 (0 %) 21 (2,7 %) (27,2 %) 555 (70,9 %) 0 (0 %) 15 (1,9 %) (29 %) 506 (69,1 %) 0 (0 %) 14 (1,9 %) (26,7 %) 535 (72,2 %) 0 (0 %) 8 (1,1 %) (25 %) 477 (73,3 %) 0 (0 %) 11 (1,7 %) (19 %) 144 (80,4 %) 0 (0 %) 1 (0,6 %) (22,3 %) (63,6 %) (9,8 %) 807 (4,4 %) Table 6: Bone transplant femur - Revisions Year of revision Yes No Bone impaction Missing (11,9 %) 594 (57 %) 69 (6,6 %) 256 (24,5 %) (14,6 %) 598 (59,3 %) 81 (8 %) 183 (18,1 %) (17,1 %) 571 (53,9 %) 86 (8,1 %) 221 (20,9 %) (13,2 %) 647 (68,9 %) 119 (12,7 %) 49 (5,2 %) (13,8 %) 726 (73,3 %) 97 (9,8 %) 30 (3 %) (18,1 %) 646 (67,6 %) 99 (10,4 %) 38 (4 %) (17,1 %) 584 (63,3 %) 150 (16,3 %) 30 (3,3 %) (22,2 %) 571 (58,6 %) 166 (17 %) 22 (2,3 %) (21,7 %) 534 (56,6 %) 186 (19,7 %) 18 (1,9 %) (20,9 %) 603 (57,4 %) 206 (19,6 %) 22 (2,1 %) (21,5 %) 581 (57,5 %) 190 (18,8 %) 23 (2,3 %) (23,4 %) 615 (61,3 %) 124 (12,4 %) 30 (3 %) (37,3 %) 586 (59,5 %) 5 (0,5 %) 27 (2,7 %) (30,3 %) 619 (68 %) 0 (0 %) 15 (1,6 %) (27,6 %) 590 (69,8 %) 0 (0 %) 22 (2,6 %) (16 %) 625 (81,3 %) 0 (0 %) 21 (2,7 %) (11,5 %) 678 (86,6 %) 0 (0 %) 15 (1,9 %) (16,9 %) 594 (81,1 %) 0 (0 %) 14 (1,9 %) (18,1 %) 599 (80,8 %) 0 (0 %) 8 (1,1 %) (13,8 %) 550 (84,5 %) 0 (0 %) 11 (1,7 %) (17,9 %) 146 (81,6 %) 0 (0 %) 1 (0,6 %) (19,5 %) (66,3 %) (8,5 %) (5,7 %) Regsitration of "Bone impaction" started in 1996 Hip 5

22 Report 2008 Operative approach Table 7: Operative approach - Primary operations Year Smith- Petersen Anterolateral Lateral Posterolateral Other Missing information (0,2 %) 403 (6,1 %) (66,3 %) (25,7 %) 9 (0,1 %) 107 (1,6 %) (0 %) 452 (7,2 %) (67,5 %) (23,4 %) 3 (0 %) 115 (1,8 %) (0,1 %) 520 (7,9 %) (67 %) (23,3 %) 4 (0,1 %) 110 (1,7 %) (0,1 %) 463 (7,4 %) (68,9 %) (23,1 %) 5 (0,1 %) 20 (0,3 %) (0,2 %) 591 (8,4 %) (68,8 %) (22,1 %) 3 (0 %) 36 (0,5 %) (0,2 %) 414 (6,7 %) (69,6 %) (22,6 %) 17 (0,3 %) 36 (0,6 %) (0,1 %) 410 (6,6 %) (69,3 %) (23,4 %) 8 (0,1 %) 27 (0,4 %) (0,3 %) 437 (7,7 %) (67,6 %) (24,2 %) 2 (0 %) 13 (0,2 %) (0,1 %) 455 (8,3 %) (67 %) (24,2 %) 8 (0,1 %) 14 (0,3 %) (0,2 %) 395 (7,4 %) (69 %) (23,2 %) 0 (0 %) 12 (0,2 %) (0,1 %) 371 (7 %) (69,9 %) (22,5 %) 1 (0 %) 26 (0,5 %) (0,1 %) 366 (7,6 %) (65,5 %) (26,2 %) 3 (0,1 %) 26 (0,5 %) (0,1 %) 311 (6,1 %) (66,3 %) (27,2 %) 8 (0,2 %) 10 (0,2 %) (0,2 %) 188 (4,1 %) (69,1 %) (26,5 %) 2 (0 %) 6 (0,1 %) (0,9 %) 226 (4,7 %) (71,2 %) (22,5 %) 12 (0,2 %) 23 (0,5 %) (0,7 %) 283 (5,8 %) (69,3 %) (23 %) 9 (0,2 %) 52 (1,1 %) (0,1 %) 260 (5,8 %) (69,1 %) (24,1 %) 1 (0 %) 37 (0,8 %) (0,1 %) 323 (6,7 %) (66,3 %) (26 %) 0 (0 %) 49 (1 %) (0,2 %) 380 (7,3 %) (61,3 %) (30,6 %) 0 (0 %) 35 (0,7 %) (0,2 %) 262 (6,7 %) (63,1 %) (29 %) 1 (0 %) 39 (1 %) (0,1 %) 119 (9 %) 840 (63,8 %) 350 (26,6 %) 2 (0,2 %) 5 (0,4 %) 221 (0,2 %) (6,9 %) (67,6 %) (24,5 %) 98 (0,1 %) 798 (0,7 %) Table 8: Operative approach - Revisions Year Smith- Petersen Anterolateral Lateral Posterolateral Other Missing information (0,1 %) 55 (5,3 %) 701 (67,2 %) 269 (25,8 %) 2 (0,2 %) 15 (1,4 %) (0,1 %) 61 (6 %) 701 (69,5 %) 231 (22,9 %) 2 (0,2 %) 13 (1,3 %) (0,3 %) 44 (4,2 %) 790 (74,6 %) 198 (18,7 %) 14 (1,3 %) 10 (0,9 %) (0,2 %) 52 (5,5 %) 731 (77,8 %) 134 (14,3 %) 1 (0,1 %) 19 (2 %) (0,1 %) 85 (8,6 %) 738 (74,5 %) 114 (11,5 %) 6 (0,6 %) 46 (4,6 %) (0,2 %) 68 (7,1 %) 722 (75,5 %) 137 (14,3 %) 8 (0,8 %) 19 (2 %) (0,5 %) 83 (9 %) 673 (73 %) 131 (14,2 %) 10 (1,1 %) 20 (2,2 %) (0,3 %) 90 (9,2 %) 737 (75,6 %) 129 (13,2 %) 11 (1,1 %) 5 (0,5 %) (0,3 %) 83 (8,8 %) 728 (77,2 %) 114 (12,1 %) 8 (0,8 %) 7 (0,7 %) (0,2 %) 73 (7 %) 827 (78,8 %) 137 (13 %) 6 (0,6 %) 5 (0,5 %) (0,2 %) 55 (5,4 %) 777 (76,9 %) 168 (16,6 %) 4 (0,4 %) 5 (0,5 %) (0 %) 73 (7,3 %) 712 (70,9 %) 202 (20,1 %) 5 (0,5 %) 12 (1,2 %) (0,1 %) 60 (6,1 %) 738 (74,9 %) 178 (18,1 %) 5 (0,5 %) 3 (0,3 %) (0,1 %) 48 (5,3 %) 685 (75,3 %) 174 (19,1 %) 1 (0,1 %) 1 (0,1 %) (0,1 %) 38 (4,5 %) 624 (73,8 %) 173 (20,5 %) 4 (0,5 %) 5 (0,6 %) (0,4 %) 40 (5,2 %) 536 (69,7 %) 179 (23,3 %) 5 (0,7 %) 6 (0,8 %) (0,1 %) 36 (4,6 %) 526 (67,2 %) 216 (27,6 %) 0 (0 %) 4 (0,5 %) (0,1 %) 43 (5,9 %) 464 (63,4 %) 220 (30,1 %) 1 (0,1 %) 3 (0,4 %) (0,4 %) 51 (6,9 %) 419 (56,5 %) 261 (35,2 %) 1 (0,1 %) 6 (0,8 %) (0,9 %) 51 (7,8 %) 347 (53,3 %) 242 (37,2 %) 0 (0 %) 5 (0,8 %) (0,6 %) 23 (12,8 %) 94 (52,5 %) 61 (34,1 %) 0 (0 %) 0 (0 %) 43 (0,2 %) (6,6 %) (71,7 %) (19,8 %) 94 (0,5 %) 209 (1,1 %) Hip

23 The Norwegian Arthroplasty Register Trochanteric osteotomy Table 9: Trochanteric osteotomy Year Primary operations Revisions No Yes Missing No Yes Missing (91,7 %) 74 (1,1 %) 480 (7,2 %) 861 (82,6 %) 109 (10,5 %) 73 (7 %) (90,5 %) 87 (1,4 %) 514 (8,1 %) 838 (83,1 %) 104 (10,3 %) 67 (6,6 %) (90,7 %) 112 (1,7 %) 499 (7,6 %) 866 (81,8 %) 102 (9,6 %) 91 (8,6 %) (96,5 %) 130 (2,1 %) 90 (1,4 %) 807 (85,9 %) 99 (10,5 %) 33 (3,5 %) (95,3 %) 213 (3 %) 121 (1,7 %) 862 (87,1 %) 97 (9,8 %) 31 (3,1 %) (95,4 %) 194 (3,1 %) 89 (1,4 %) 824 (86,2 %) 104 (10,9 %) 28 (2,9 %) (96,3 %) 157 (2,5 %) 74 (1,2 %) 776 (84,2 %) 120 (13 %) 26 (2,8 %) (96,8 %) 121 (2,1 %) 59 (1 %) 842 (86,4 %) 118 (12,1 %) 15 (1,5 %) (96,2 %) 176 (3,2 %) 30 (0,5 %) 811 (86 %) 121 (12,8 %) 11 (1,2 %) (94,1 %) 282 (5,3 %) 31 (0,6 %) 904 (86,1 %) 131 (12,5 %) 15 (1,4 %) (93,5 %) 302 (5,7 %) 46 (0,9 %) 881 (87,1 %) 115 (11,4 %) 15 (1,5 %) (92,4 %) 311 (6,4 %) 54 (1,1 %) 882 (87,8 %) 98 (9,8 %) 24 (2,4 %) (90 %) 491 (9,6 %) 17 (0,3 %) 827 (84 %) 154 (15,6 %) 4 (0,4 %) (89 %) 495 (10,7 %) 11 (0,2 %) 781 (85,8 %) 120 (13,2 %) 9 (1 %) (86,8 %) 593 (12,3 %) 44 (0,9 %) 723 (85,6 %) 113 (13,4 %) 9 (1,1 %) (85,6 %) 630 (12,9 %) 73 (1,5 %) 656 (85,3 %) 103 (13,4 %) 10 (1,3 %) (81,2 %) 790 (17,6 %) 54 (1,2 %) 626 (79,9 %) 146 (18,6 %) 11 (1,4 %) (76,9 %) (21,9 %) 54 (1,1 %) 553 (75,5 %) 169 (23,1 %) 10 (1,4 %) (76,1 %) (22,4 %) 76 (1,5 %) 539 (72,7 %) 197 (26,6 %) 5 (0,7 %) (73,2 %) 997 (25,4 %) 54 (1,4 %) 434 (66,7 %) 206 (31,6 %) 11 (1,7 %) (72,9 %) 338 (25,7 %) 19 (1,4 %) 126 (70,4 %) 52 (29,1 %) 1 (0,6 %) (89,9 %) (7,9 %) (2,2 %) (83,4 %) (13,9 %) 499 (2,7 %) Systemic antibiotic prophylaxis Table 10: Systemic antibiotic prophylaxis Primary operations Revisions Year No Yes Missing No Yes Missing (0,4 %) (99,5 %) 7 (0,1 %) 29 (2,8 %) (96,5 %) 7 (0,7 %) (0,6 %) (99,4 %) 0 (0 %) 28 (2,8 %) 981 (97,2 %) 0 (0 %) (0,3 %) (99,7 %) 0 (0 %) 19 (1,8 %) (98,2 %) 0 (0 %) (0 %) (100 %) 0 (0 %) 6 (0,6 %) 928 (98,8 %) 5 (0,5 %) (0 %) (100 %) 1 (0 %) 8 (0,8 %) 975 (98,5 %) 7 (0,7 %) (0,1 %) (99,9 %) 2 (0 %) 10 (1 %) 943 (98,6 %) 3 (0,3 %) (0,2 %) (99,8 %) 2 (0 %) 3 (0,3 %) 918 (99,6 %) 1 (0,1 %) (0,2 %) (99,8 %) 1 (0 %) 6 (0,6 %) 969 (99,4 %) 0 (0 %) (0,1 %) (99,9 %) 1 (0 %) 5 (0,5 %) 935 (99,2 %) 3 (0,3 %) (0,2 %) (99,8 %) 1 (0 %) 6 (0,6 %) (99,4 %) 0 (0 %) (0,1 %) (99,9 %) 0 (0 %) 5 (0,5 %) (99,3 %) 2 (0,2 %) (0,1 %) (99,9 %) 0 (0 %) 10 (1 %) 993 (98,9 %) 1 (0,1 %) (0,2 %) (99,7 %) 1 (0 %) 3 (0,3 %) 982 (99,7 %) 0 (0 %) (0,6 %) (99,4 %) 1 (0 %) 12 (1,3 %) 898 (98,7 %) 0 (0 %) (1,2 %) (98,8 %) 3 (0,1 %) 12 (1,4 %) 832 (98,5 %) 1 (0,1 %) (2,2 %) (97,7 %) 5 (0,1 %) 16 (2,1 %) 746 (97 %) 7 (0,9 %) (3,1 %) (96,7 %) 13 (0,3 %) 24 (3,1 %) 755 (96,4 %) 4 (0,5 %) (4,8 %) (95,2 %) 4 (0,1 %) 18 (2,5 %) 711 (97,1 %) 3 (0,4 %) (8,8 %) (91,1 %) 6 (0,1 %) 36 (4,9 %) 703 (94,9 %) 2 (0,3 %) (14 %) (85,8 %) 9 (0,2 %) 45 (6,9 %) 602 (92,5 %) 4 (0,6 %) (16,9 %) (82,8 %) 5 (0,4 %) 13 (7,3 %) 164 (91,6 %) 2 (1,1 %) (1,8 %) (98,2 %) 62 (0,1 %) 314 (1,7 %) (98 %) 52 (0,3 %) Hip 7

24 Report 2008 Use of cement in primary operations Figure 5: Use of cement in primary operations - All patients Proportion of primary operations 100 % 80 % 60 % 40 % 20 % 0 % Figure 6: Use of cement in primary operations - Patients < 60 years Proportion of primary operations 100 % 80 % 60 % 40 % 20 % 0 % Figure 7: Use of cement in primary operations - Patients >= 60 years Proportion of primary operations 100 % 80 % 60 % 40 % 20 % 0 % Cemented (containing antibiotic) Cemented (plain) Uncemented Hybrid, cemented acetabulum Hybrid, cemented femur Other / Missing information 8 Hip

25 The Norwegian Arthroplasty Register Use of cement in revisions Table 11: Use of cement in revisions - Acetabulum With antibiotic Without antibiotic Uncemented Missing information >=60 yrs <60 yrs All >=60 yrs <60 yrs All >=60 yrs <60 yrs All >=60 yrs <60 yrs All >=60 yrs <60 yrs All % 51% 59% 0% 0% 0% 42% 48% 41% 0% 1% 0% % 54% 61% 0% 0% 0% 40% 46% 39% 0% 0% 0% % 60% 64% 0% 0% 0% 37% 40% 36% 0% 0% 0% % 58% 68% 0% 0% 0% 33% 42% 32% 0% 0% 0% % 66% 68% 0% 0% 1% 32% 34% 31% 0% 0% 0% % 68% 63% 1% 1% 1% 35% 31% 36% 0% 0% 0% % 53% 61% 3% 5% 2% 38% 42% 37% 0% 0% 0% % 52% 63% 0% 1% 0% 39% 47% 37% 0% 1% 0% % 51% 65% 0% 1% 0% 37% 48% 34% 0% 0% 0% % 55% 66% 1% 0% 1% 35% 45% 33% 0% 0% 0% % 44% 58% 0% 1% 0% 45% 56% 42% 0% 0% 0% % 35% 56% 1% 0% 1% 46% 65% 42% 0% 0% 1% % 34% 58% 0% 0% 1% 46% 66% 41% 1% 0% 1% % 30% 53% 1% 0% 1% 49% 70% 45% 0% 0% 0% % 19% 52% 1% 2% 1% 53% 79% 46% 0% 0% 0% % 32% 65% 3% 0% 3% 37% 64% 31% 1% 3% 1% % 34% 63% 3% 1% 4% 36% 62% 31% 3% 2% 3% % 32% 68% 2% 0% 2% 34% 65% 27% 3% 3% 3% % 36% 73% 3% 0% 4% 29% 61% 22% 1% 3% 1% % 46% 74% 4% 0% 5% 24% 51% 18% 2% 4% 2% % 50% 76% 3% 0% 3% 23% 50% 19% 1% 0% 2% % 46% 63% 1% 1% 1% 38% 53% 35% 1% 1% 1% Table 12: Use of cement in revisions - Femur With antibiotic Without antibiotic Uncemented Missing information >=60 yrs <60 yrs All >=60 yrs <60 yrs All >=60 yrs <60 yrs All >=60 yrs <60 yrs All >=60 yrs <60 yrs All % 23% 36% 0% 0% 0% 66% 77% 64% 0% 0% 0% % 20% 39% 0% 0% 0% 63% 80% 61% 0% 0% 0% % 35% 41% 0% 0% 0% 60% 65% 59% 0% 0% 0% % 31% 57% 0% 0% 0% 47% 69% 43% 0% 0% 0% % 52% 61% 0% 0% 0% 39% 48% 38% 0% 0% 0% % 67% 60% 1% 2% 1% 38% 31% 39% 0% 0% 0% % 42% 62% 1% 0% 1% 39% 58% 37% 0% 0% 0% % 59% 64% 0% 0% 0% 36% 41% 35% 1% 0% 1% % 48% 69% 0% 0% 0% 34% 52% 31% 0% 0% 0% % 52% 68% 0% 0% 0% 33% 47% 31% 1% 1% 1% % 53% 65% 0% 0% 1% 36% 47% 34% 0% 0% 0% % 43% 67% 2% 1% 2% 34% 56% 30% 1% 0% 1% % 40% 65% 3% 3% 3% 35% 57% 31% 1% 0% 1% % 31% 61% 5% 2% 5% 38% 67% 33% 1% 0% 1% % 28% 61% 3% 3% 4% 41% 69% 36% 0% 0% 0% % 52% 75% 4% 3% 5% 23% 43% 19% 2% 1% 2% % 50% 74% 5% 2% 6% 21% 45% 16% 4% 3% 4% % 40% 75% 3% 2% 4% 23% 54% 16% 5% 5% 6% % 44% 80% 4% 1% 4% 21% 52% 13% 2% 3% 2% % 46% 80% 4% 0% 4% 19% 46% 13% 4% 9% 3% % 42% 80% 5% 0% 5% 17% 47% 13% 3% 11% 2% % 43% 64% 2% 1% 2% 36% 55% 33% 1% 1% 1% Hip 9