Session 10: Knee arthroplasty
14. November
14:30 - 16:00
Lokale: Skovbrynet
Chair: Anders El-Ghalaly & Thomas Lind-Hansen
Mikkel Andreas Hansen1, Claus Varnum1,2, Signe Timm1,2, Lasse E. Rasmussen1
1. Department of Orthopedic Surgery, Lillebaelt Hospital - Vejle, University Hospital of Southern Denmark 2. Department of Regional Health Research, University of Southern Denmark, Denmark
Background: Tourniquet application during total knee arthroplasty (TKA) is a common practice aimed at reducing intraoperative bleeding. However, concerns have been raised about potential tissue damage from ischemia and reperfusion injury.
Aim: This study examines the effects of tourniquet use during TKA on postoperative functional outcomes, including pain, range of motion (ROM), and patient- reported outcome measures (PROMs), specifically the Forgotten Joint Score (FJS) and Oxford Knee Score (OKS).
Materials and Methods: In a fast-track setting, a randomized, single-blinded controlled trial was conducted with patients undergoing bilateral TKA. Tourniquets were applied to one knee, while the contralateral knee served as a control. Evaluations were conducted after two and four weeks, and at three and twelve months postoperatively, employing paired t-tests and mixed- effects linear regression modeling for statistical analysis.
Results: Among the 22 participants who completed the study, no significant differences were observed in pain levels at two weeks or in PROMs at any time point between the tourniquet and control groups. While a modest increase in one-year ROM was noted in the tourniquet group, it was considered a clinically irrelevant difference.
Interpretation / Conclusion: Tourniquet use in TKA does not affect early pain levels or long-term functional outcomes in patients undergoing bilateral TKA, suggesting that its benefits in surgical efficiency do not compromise patient recovery or long-term outcomes.
1. Department of Orthopedic Surgery, Lillebaelt Hospital - Vejle, University Hospital of Southern Denmark 2. Department of Regional Health Research, University of Southern Denmark, Denmark
Background: Tourniquet application during total knee arthroplasty (TKA) is a common practice aimed at reducing intraoperative bleeding. However, concerns have been raised about potential tissue damage from ischemia and reperfusion injury.
Aim: This study examines the effects of tourniquet use during TKA on postoperative functional outcomes, including pain, range of motion (ROM), and patient- reported outcome measures (PROMs), specifically the Forgotten Joint Score (FJS) and Oxford Knee Score (OKS).
Materials and Methods: In a fast-track setting, a randomized, single-blinded controlled trial was conducted with patients undergoing bilateral TKA. Tourniquets were applied to one knee, while the contralateral knee served as a control. Evaluations were conducted after two and four weeks, and at three and twelve months postoperatively, employing paired t-tests and mixed- effects linear regression modeling for statistical analysis.
Results: Among the 22 participants who completed the study, no significant differences were observed in pain levels at two weeks or in PROMs at any time point between the tourniquet and control groups. While a modest increase in one-year ROM was noted in the tourniquet group, it was considered a clinically irrelevant difference.
Interpretation / Conclusion: Tourniquet use in TKA does not affect early pain levels or long-term functional outcomes in patients undergoing bilateral TKA, suggesting that its benefits in surgical efficiency do not compromise patient recovery or long-term outcomes.
Julius Tetens Hald1, Anders Brændsgaard El-Galaly1, Michael Mørk Petersen1, 2, Martin Lindberg-Larsen3, Robin Christensen4,5, Anders Odgaard1,2,
1. Department of Orthopedic Surgery, Rigshospitalet, Copenhagen University. 2. Department of Clinical Medicine, University of Copenhagen, Copenhagen. 3. Department of Orthopedic Surgery and Traumatology, Odense University Hospital 4. Section for Biostatistics and Evidence-Based Research, the Parker Institute, Bispebjerg and Frederiksberg Hospital, Copenhagen 5. Research Unit of Rheumatology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital
Background: The use of both primary and revision knee arthroplasties is rising and more patients are expected to undergo multiple implant revisions within their lifetime. These patients represent a complex population with severe complications, disabilities, and healthcare costs. They pose a challenge to both surgeons and healthcare systems in general. Healthcare systems will require increasing resources to address this problem, but most importantly more knowledge is needed. S
Aim: To ascertain the absolute incidence and implant survival rates of knee arthroplasties and those who subsequently underwent multiple revisions in Denmark between 1998 and 2021.
Materials and Methods: A retrospective observational study of several nationwide Danish registers (clinicaltrials.gov identifier: NCT06064318). From the registers, all primary knee arthroplasty procedures performed in Denmark from 1998 to 2021 were identified. From these primary arthroplasties, revision procedures were identified; these were also categorized by the number of previous revisions. Kaplan-Meier plots were used in survival analysis to estimate the likelihood of implant survival.
Results: Between 1998 and 2021, 161,384 primary knee arthroplasties were identified; among these a total of 13,787 (8.5%) revisions were identified. There were 10,638 1st revisions, 2,148 2nd revisions, 624 3rd revisions, 223 4th revisions, and 153 procedures which had been revised more than 4 times; casuistically, the highest number of revisions performed in this period on a single knee was 11. The 10-year survival of primary arthroplasties was 92.3% (95% CI 92.2 to 92.5%). Among primary failures: first-time revisions had a 10-year survival of 75.9% (95% CI 74.9 to 76.9%). The 10-year survival of second- and third-time revisions was 65.1% (95% CI 62.6 to 67.6%) and 57.8% (95% CI 53.4 to 62.5%), respectively.
Interpretation / Conclusion: This study has identified that 0.6% of all primary knee arthroplasties performed in Denmark from 1998-2021 resulted in 3 or more revisions. The implant survival decreased for each consecutive revision, with almost half of the third-time revisions being re-revised within 10 years.
1. Department of Orthopedic Surgery, Rigshospitalet, Copenhagen University. 2. Department of Clinical Medicine, University of Copenhagen, Copenhagen. 3. Department of Orthopedic Surgery and Traumatology, Odense University Hospital 4. Section for Biostatistics and Evidence-Based Research, the Parker Institute, Bispebjerg and Frederiksberg Hospital, Copenhagen 5. Research Unit of Rheumatology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital
Background: The use of both primary and revision knee arthroplasties is rising and more patients are expected to undergo multiple implant revisions within their lifetime. These patients represent a complex population with severe complications, disabilities, and healthcare costs. They pose a challenge to both surgeons and healthcare systems in general. Healthcare systems will require increasing resources to address this problem, but most importantly more knowledge is needed. S
Aim: To ascertain the absolute incidence and implant survival rates of knee arthroplasties and those who subsequently underwent multiple revisions in Denmark between 1998 and 2021.
Materials and Methods: A retrospective observational study of several nationwide Danish registers (clinicaltrials.gov identifier: NCT06064318). From the registers, all primary knee arthroplasty procedures performed in Denmark from 1998 to 2021 were identified. From these primary arthroplasties, revision procedures were identified; these were also categorized by the number of previous revisions. Kaplan-Meier plots were used in survival analysis to estimate the likelihood of implant survival.
Results: Between 1998 and 2021, 161,384 primary knee arthroplasties were identified; among these a total of 13,787 (8.5%) revisions were identified. There were 10,638 1st revisions, 2,148 2nd revisions, 624 3rd revisions, 223 4th revisions, and 153 procedures which had been revised more than 4 times; casuistically, the highest number of revisions performed in this period on a single knee was 11. The 10-year survival of primary arthroplasties was 92.3% (95% CI 92.2 to 92.5%). Among primary failures: first-time revisions had a 10-year survival of 75.9% (95% CI 74.9 to 76.9%). The 10-year survival of second- and third-time revisions was 65.1% (95% CI 62.6 to 67.6%) and 57.8% (95% CI 53.4 to 62.5%), respectively.
Interpretation / Conclusion: This study has identified that 0.6% of all primary knee arthroplasties performed in Denmark from 1998-2021 resulted in 3 or more revisions. The implant survival decreased for each consecutive revision, with almost half of the third-time revisions being re-revised within 10 years.
Stefan Risager1, Bjarke Viberg1, Martin Lindberg-Larsen1, Kristine Arndt2, Charlotte Abrahamsen3, Anders Odgaard4
1 Department of Orthopaedic and traumatology, Odense University Hospital 2 Department of Orthopaedic Surgery and Traumatology, Hospital Lillebaelt, Kolding 3 Department of Orthopaedic Surgery and Traumatology, Rigshospitalet, København
Background: Periprosthetic knee fractures (PPKF) following total knee arthroplasty (TKA) are uncommon, but potentially serious injuries.
Aim: To analyze the risk and risk factors for a PPKF in standard primary TKA patients with osteoarthritis (OA) and a minimally (cruciate retaining TKA’s without femoral box cut) or posterior stabilized TKA. In addition, to report the risk for patients with other underlying knee disorders and/or a higher level of TKA constraint.
Materials and Methods: A nationwide cohort study using register data between 1997 and 2022. All primary TKA were identified from the Danish National Patient Register and the Danish Knee Arthroplasty Register. Subsequent fractures were identified through ICD diagnosis code, NOMESCO procedure code or indication for revision TKA.
Results: We included 120,642 standard primary TKA patients with 1,434 PPKF´s. The cumulated proportions were 0.3% (95% CI 0.3-0.3) at 2 years, 0.7% (0.6-0.7) at 5 years and at 10 years it was 1.5% (1.4-1.6) with 1.2% in the femur, 0.2% in the patella and 0.1% tibia. Significant risk factors were (Hazard Ratio (95% CI)); ipsilateral hip arthroplasty (2.5 (2.1-2.8)), female sex (2.0 (1.8-2.3)), osteoporosis (1.4 (1.1-1.7)), age 80+ (1.4 (1.2-1.6)), Charlson Comorbidity Index (CCI) score 3+ (1.4 (1.0-1.8)). Additional 22,624 primary TKA patients with other underlying knee disorders and/or higher level of implant constraint were included with 485 PPKF’s. The 10-year cumulated proportion were 5.5% (95% CI 4.4-6.9) when underlying disorder was previous fracture, 2.3% (1.7-2.9) for rheumatic disorders and 3.5% (1.4-8.8) for osteonecrosis. In patients with condylar constrained knees it was 4.3% (2.9-6.3) and 7.3% (4.1-13.1) for hinges.
Interpretation / Conclusion: In standard primary TKA patients, the 10 year cumulated proportion of PPKF’s was 1.5% and ipsilateral hip arthroplasty, female sex, osteoporosis, advanced age, and higher CCI increased the risk. Higher risks were observed in non-OA patients and/or patients with higher level of TKA constraint.
1 Department of Orthopaedic and traumatology, Odense University Hospital 2 Department of Orthopaedic Surgery and Traumatology, Hospital Lillebaelt, Kolding 3 Department of Orthopaedic Surgery and Traumatology, Rigshospitalet, København
Background: Periprosthetic knee fractures (PPKF) following total knee arthroplasty (TKA) are uncommon, but potentially serious injuries.
Aim: To analyze the risk and risk factors for a PPKF in standard primary TKA patients with osteoarthritis (OA) and a minimally (cruciate retaining TKA’s without femoral box cut) or posterior stabilized TKA. In addition, to report the risk for patients with other underlying knee disorders and/or a higher level of TKA constraint.
Materials and Methods: A nationwide cohort study using register data between 1997 and 2022. All primary TKA were identified from the Danish National Patient Register and the Danish Knee Arthroplasty Register. Subsequent fractures were identified through ICD diagnosis code, NOMESCO procedure code or indication for revision TKA.
Results: We included 120,642 standard primary TKA patients with 1,434 PPKF´s. The cumulated proportions were 0.3% (95% CI 0.3-0.3) at 2 years, 0.7% (0.6-0.7) at 5 years and at 10 years it was 1.5% (1.4-1.6) with 1.2% in the femur, 0.2% in the patella and 0.1% tibia. Significant risk factors were (Hazard Ratio (95% CI)); ipsilateral hip arthroplasty (2.5 (2.1-2.8)), female sex (2.0 (1.8-2.3)), osteoporosis (1.4 (1.1-1.7)), age 80+ (1.4 (1.2-1.6)), Charlson Comorbidity Index (CCI) score 3+ (1.4 (1.0-1.8)). Additional 22,624 primary TKA patients with other underlying knee disorders and/or higher level of implant constraint were included with 485 PPKF’s. The 10-year cumulated proportion were 5.5% (95% CI 4.4-6.9) when underlying disorder was previous fracture, 2.3% (1.7-2.9) for rheumatic disorders and 3.5% (1.4-8.8) for osteonecrosis. In patients with condylar constrained knees it was 4.3% (2.9-6.3) and 7.3% (4.1-13.1) for hinges.
Interpretation / Conclusion: In standard primary TKA patients, the 10 year cumulated proportion of PPKF’s was 1.5% and ipsilateral hip arthroplasty, female sex, osteoporosis, advanced age, and higher CCI increased the risk. Higher risks were observed in non-OA patients and/or patients with higher level of TKA constraint.
Abdullahi Abdirisak Hirsi1,2, Oddrún Danielsen Danielsen 1,2, Claus Varnum1,3, Thomas Jakobsen1,4, Mikkel Rathsach Andersen1,5, Manuel Josef Bieder1,6, Søren Overgaard1,7, Christoffer Calov Jørgensen1,8, Henrik Kehlet1,9, Kirill Gromov1,10, Martin Lindberg-Larsen1,2
1Center for Fast-track Hip and Knee Replacement, Denmark 2Dept. of Orthopaedic Surgery and traumatology, Odense University Hospital and Svendborg 3Dept. of Orthopaedic Surgery, Lillebaelt Hospital – Vejle 4Dept. of Orthopaedic Surgery, Aalborg University Hospital 5Dept. of Orthopaedic Surgery, Copenhagen University Hospital, Herlev- Gentofte 6Dept. of Orthopaedic surgery, Næstved, Slagelse and Ringsted Hospitals 7Dept. of Orthopaedic Surgery and Traumatology, Copenhagen University Hospital, Bispebjerg 8Dept. of Anaesthesia, Hospital of Northern Zeeland, Hillerød 9Section of Surgical Pathophysiology, Copenhagen University Hospital, Rigshospitalet 10Dept. of Orthopaedic Surgery, Hvidovre University Hospital
Background: Day case surgery following primary hip and knee arthroplasty is feasible in over 20% of patients in a public healthcare setting.The day- case patient rate may increase further,but it is concerning if it results in additional post- discharge healthcare system contacts.
Aim: To investigate whether day-case surgery leads to increased patient-reported healthcare system contacts compared to non day-case surgery within the first 30 days postoperatively.
Materials and Methods: This was a prospective multicentre study from seven fast-track centres between September 2022 to August 2023.Candidates for THA, TKA and UKA were evaluated for day-case eligibility using defined criteria.Patients were surveyed 30 days postoperatively regarding any healthcare system contacts related to surgery.Planned health care visits were excluded.We used day- case eligible patients not discharged on day of surgery (inpatients) as control group.
Results: 2251 day-case eligible patients received the survey and 1960 completed the survey (87%).We investigated 1140 day-case patients (58%) and 820 (42%) inpatients (control group).Baseline demographics were comparable between groups regarding age,gender,BMI,Clinical Frailty Scale,social status and comorbidity profile.Mean age was 68 years,39% were THA,36% TKA and 35% UKA.The overall rate of healthcare system contacts was 46% in day-case patients vs. 50% in inpatients,P=0.030.Specific contacts included 23% contacts to general practitioner (GP) or doctor on call in day-cases vs. 30% in inpatients.Main reasons for contact to GP or doctor on call were wound complications (6.1% in day-cases vs 7.0% in inpatients), prescription renewals (4.7% vs. 5.7%),and pain management (3.3% vs. 6.5%). Emergency Department (ED)contacts were reported by 6.2% of day-cases vs. 6.3% of inpatients,primarily for wound issues (1.7% vs.1.6%),suspected DVT (1.6% vs.0.7%), and swelling (0.8%vs.1.0%).Outpatient clinic or ward contacts were reported by 36% of day-cases vs. 37% of inpatients,mainly for pain management (9.5% vs.10%), wound problems(10% vs.8.3%),and swelling(4.0% vs.5.9%).
Interpretation / Conclusion: Day-case hip and knee arthroplasty was not associated with increased healthcare system contacts within first 30 days postoperatively.
1Center for Fast-track Hip and Knee Replacement, Denmark 2Dept. of Orthopaedic Surgery and traumatology, Odense University Hospital and Svendborg 3Dept. of Orthopaedic Surgery, Lillebaelt Hospital – Vejle 4Dept. of Orthopaedic Surgery, Aalborg University Hospital 5Dept. of Orthopaedic Surgery, Copenhagen University Hospital, Herlev- Gentofte 6Dept. of Orthopaedic surgery, Næstved, Slagelse and Ringsted Hospitals 7Dept. of Orthopaedic Surgery and Traumatology, Copenhagen University Hospital, Bispebjerg 8Dept. of Anaesthesia, Hospital of Northern Zeeland, Hillerød 9Section of Surgical Pathophysiology, Copenhagen University Hospital, Rigshospitalet 10Dept. of Orthopaedic Surgery, Hvidovre University Hospital
Background: Day case surgery following primary hip and knee arthroplasty is feasible in over 20% of patients in a public healthcare setting.The day- case patient rate may increase further,but it is concerning if it results in additional post- discharge healthcare system contacts.
Aim: To investigate whether day-case surgery leads to increased patient-reported healthcare system contacts compared to non day-case surgery within the first 30 days postoperatively.
Materials and Methods: This was a prospective multicentre study from seven fast-track centres between September 2022 to August 2023.Candidates for THA, TKA and UKA were evaluated for day-case eligibility using defined criteria.Patients were surveyed 30 days postoperatively regarding any healthcare system contacts related to surgery.Planned health care visits were excluded.We used day- case eligible patients not discharged on day of surgery (inpatients) as control group.
Results: 2251 day-case eligible patients received the survey and 1960 completed the survey (87%).We investigated 1140 day-case patients (58%) and 820 (42%) inpatients (control group).Baseline demographics were comparable between groups regarding age,gender,BMI,Clinical Frailty Scale,social status and comorbidity profile.Mean age was 68 years,39% were THA,36% TKA and 35% UKA.The overall rate of healthcare system contacts was 46% in day-case patients vs. 50% in inpatients,P=0.030.Specific contacts included 23% contacts to general practitioner (GP) or doctor on call in day-cases vs. 30% in inpatients.Main reasons for contact to GP or doctor on call were wound complications (6.1% in day-cases vs 7.0% in inpatients), prescription renewals (4.7% vs. 5.7%),and pain management (3.3% vs. 6.5%). Emergency Department (ED)contacts were reported by 6.2% of day-cases vs. 6.3% of inpatients,primarily for wound issues (1.7% vs.1.6%),suspected DVT (1.6% vs.0.7%), and swelling (0.8%vs.1.0%).Outpatient clinic or ward contacts were reported by 36% of day-cases vs. 37% of inpatients,mainly for pain management (9.5% vs.10%), wound problems(10% vs.8.3%),and swelling(4.0% vs.5.9%).
Interpretation / Conclusion: Day-case hip and knee arthroplasty was not associated with increased healthcare system contacts within first 30 days postoperatively.
Anders El-Galaly1, Per Hviid Gundtoft2, Claus Moser3, Anders Odgaard1, Alma Becic Pedersen4
1. Department of Orthopedic Surgery, Copenhagen University Hospital - Rigshospitalet 2. Department of Orthopedic Surgery, Aarhus University Hospital 3. Department of Clinical Microbiology, Copenhagen University Hospital - Rigshospitalet 4. Department of Clinical Epidemiology, Aarhus University
Background: Periprosthetic joint infection (PJI) is a severe and potential lethal complication in hip- or knee arthroplasty surgery. Yet, little attention has been giving to the fact that the most common bacteria causing PJI also causes other lethal infections, such as infectious endocarditis (IE). A recent case series reported a mortality of almost 40% in patients with concomitant PJI and IE. Yet, up till now, no studies have investigated the risk of IE in patients with PJI.
Aim: To investigate the risk of concomitant PJI and IE and the 1-year mortality in these patients.
Materials and Methods: The study cohort were defined by patients registered in the Danish Hip - or Knee Arthroplasty Register with revision due to infection between 1996 and 2019. Utilizing the unique Danish social security number, the observations were merged with data from the Danish National Patient Register where IE was defined by ICD-10 codes of DI33, DI38 and DI398, accompanied by a minimum of 14 days hospital admission to ensure the validity. Concomitant PJI and IE was defined as IE diagnosed 3 months before or 6 months after surgery for PJI. The 1-year mortality were calculated from the latter event of either surgery or IE. Risk and mortality were denoted as percentages with 95% confidence intervals. In accordance with Statistics Denmark’s guidelines, n<5 was not reported in absolute numbers.
Results: In total, 3,452 PJIs distributed in 2,085 hips and 1,367 knees were included. Among these, 24 had IE 3 months before surgery and 14 within 6 months after surgery. This corresponded to a risk of 1.1% (95% CI: 0.75-1.4). Within 1-year, 5 patients with concomitant hip-PJI and IE died compared to <5 for knee-PJI. Thus, the estimated 1-year mortality ranged between 13% and 24% (95% CI: 2.4-37) (data limitation due to knee-PJI <5).
Interpretation / Conclusion: In Denmark, the risk of IE in patients treated for PJI of the hip or knee is low and we were unable to confirm the exceedingly high mortality reported in the recent case series. Although IE might be under diagnosed in our current practice, it does not seem to be a critical clinical challenge in the treatment of PJI in the hip or knee.
1. Department of Orthopedic Surgery, Copenhagen University Hospital - Rigshospitalet 2. Department of Orthopedic Surgery, Aarhus University Hospital 3. Department of Clinical Microbiology, Copenhagen University Hospital - Rigshospitalet 4. Department of Clinical Epidemiology, Aarhus University
Background: Periprosthetic joint infection (PJI) is a severe and potential lethal complication in hip- or knee arthroplasty surgery. Yet, little attention has been giving to the fact that the most common bacteria causing PJI also causes other lethal infections, such as infectious endocarditis (IE). A recent case series reported a mortality of almost 40% in patients with concomitant PJI and IE. Yet, up till now, no studies have investigated the risk of IE in patients with PJI.
Aim: To investigate the risk of concomitant PJI and IE and the 1-year mortality in these patients.
Materials and Methods: The study cohort were defined by patients registered in the Danish Hip - or Knee Arthroplasty Register with revision due to infection between 1996 and 2019. Utilizing the unique Danish social security number, the observations were merged with data from the Danish National Patient Register where IE was defined by ICD-10 codes of DI33, DI38 and DI398, accompanied by a minimum of 14 days hospital admission to ensure the validity. Concomitant PJI and IE was defined as IE diagnosed 3 months before or 6 months after surgery for PJI. The 1-year mortality were calculated from the latter event of either surgery or IE. Risk and mortality were denoted as percentages with 95% confidence intervals. In accordance with Statistics Denmark’s guidelines, n<5 was not reported in absolute numbers.
Results: In total, 3,452 PJIs distributed in 2,085 hips and 1,367 knees were included. Among these, 24 had IE 3 months before surgery and 14 within 6 months after surgery. This corresponded to a risk of 1.1% (95% CI: 0.75-1.4). Within 1-year, 5 patients with concomitant hip-PJI and IE died compared to <5 for knee-PJI. Thus, the estimated 1-year mortality ranged between 13% and 24% (95% CI: 2.4-37) (data limitation due to knee-PJI <5).
Interpretation / Conclusion: In Denmark, the risk of IE in patients treated for PJI of the hip or knee is low and we were unable to confirm the exceedingly high mortality reported in the recent case series. Although IE might be under diagnosed in our current practice, it does not seem to be a critical clinical challenge in the treatment of PJI in the hip or knee.
Anders Bagge1, Christian Bredgaard Jensen1, Christian Skovgaard Nielsen1, Kirill Gromov1, Anders Troelsen1
1. Clinical Orthopaedic Research Hvidovre (CORH), Department of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre
Background: The usage of unicompartmental knee arthroplasty (UKA) has been on the rise throughout the last decade, accounting for between 11 and 26 percent of all primary knee arthroplasties in national registers. Contemporary evidence-based indications no longer consider age regarding eligibility for UKA, however, some surgeons are still reluctant to perform the procedure on younger patients. As these less strict criteria have led to more UKA candidates, the question of interest is whether or not patients still have satisfactory outcomes after surgery. Furthermore, the impact of age on the short-term improvements after medial UKA lacks evidence.
Aim: This study examines the association between age and the development of patient reported outcome measures (PROMs) after medial unicompartmental knee arthroplasty (mUKA) as well as the achievement of Patient Acceptable Symptom State (PASS) and Minimal Important Change (MIC).
Materials and Methods: 782 mUKAs performed between February 1, 2016 and April 26, 2023 were included. The development from preoperative Oxford Knee Score (?OKS), Forgotten Joint Score (?FJS) and Activity and Participation Questionnaire (?APQ) was assessed at 3, 12 and 24 months after surgery as well as the achievement of PASS (OKS=30) and MIC (?OKS=8, ?FJS=14) at 12 months. Patients were divided into groups based on age: <55, 55 to <65, 65 to <75 (reference group), and =75 years. 432 patients were women (55%), mean age was 67 (SD 9.2) years and mean BMI was 30 (SD 5.7) kg/m2.
Results: Median OKS, from youngest to eldest group, were 34, 35, 36, and 35 (3 months); 40, 39, 41, and 43 (12 months); 42, 41, 43, and 42 (24 months). We found no differences in ?OKS between groups at follow-up. Patients aged 55 to <65 years had lower 24-month ?FJS and lower ?APQ at 12 and 24 months. Patients aged =75 years also had lower 24-month ?APQ. We found no association between age and the fraction of patients achieving PASS (range 81-89%) or MIC (ranges 78-81% (?OKS); 81-90% (?FJS)).
Interpretation / Conclusion: This study found good PROM improvements and satisfactory outcomes after mUKA in all age groups. However, minor differences in activity and participation were present in very young and elderly patients.
1. Clinical Orthopaedic Research Hvidovre (CORH), Department of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre
Background: The usage of unicompartmental knee arthroplasty (UKA) has been on the rise throughout the last decade, accounting for between 11 and 26 percent of all primary knee arthroplasties in national registers. Contemporary evidence-based indications no longer consider age regarding eligibility for UKA, however, some surgeons are still reluctant to perform the procedure on younger patients. As these less strict criteria have led to more UKA candidates, the question of interest is whether or not patients still have satisfactory outcomes after surgery. Furthermore, the impact of age on the short-term improvements after medial UKA lacks evidence.
Aim: This study examines the association between age and the development of patient reported outcome measures (PROMs) after medial unicompartmental knee arthroplasty (mUKA) as well as the achievement of Patient Acceptable Symptom State (PASS) and Minimal Important Change (MIC).
Materials and Methods: 782 mUKAs performed between February 1, 2016 and April 26, 2023 were included. The development from preoperative Oxford Knee Score (?OKS), Forgotten Joint Score (?FJS) and Activity and Participation Questionnaire (?APQ) was assessed at 3, 12 and 24 months after surgery as well as the achievement of PASS (OKS=30) and MIC (?OKS=8, ?FJS=14) at 12 months. Patients were divided into groups based on age: <55, 55 to <65, 65 to <75 (reference group), and =75 years. 432 patients were women (55%), mean age was 67 (SD 9.2) years and mean BMI was 30 (SD 5.7) kg/m2.
Results: Median OKS, from youngest to eldest group, were 34, 35, 36, and 35 (3 months); 40, 39, 41, and 43 (12 months); 42, 41, 43, and 42 (24 months). We found no differences in ?OKS between groups at follow-up. Patients aged 55 to <65 years had lower 24-month ?FJS and lower ?APQ at 12 and 24 months. Patients aged =75 years also had lower 24-month ?APQ. We found no association between age and the fraction of patients achieving PASS (range 81-89%) or MIC (ranges 78-81% (?OKS); 81-90% (?FJS)).
Interpretation / Conclusion: This study found good PROM improvements and satisfactory outcomes after mUKA in all age groups. However, minor differences in activity and participation were present in very young and elderly patients.
Stefan Risager1, Kristine Arndt2, Charlotte Abrahamsen2, Bjarke Viberg1, Anders Odgaard3, Martin Lindberg-Larsen1
1. Department of Orthopaedic and traumatology, Odense University Hospital 2. Department of Orthopaedic Surgery and Traumatology, Hospital Lillebaelt, Kolding 3. Department of Orthopaedic Surgery and Traumatology, Rigshospitalet, København
Background: Periprosthetic Knee Fracture (PPKF) following Total Knee Arthroplasty (TKA) can be difficult to treat. Treatment options include plating, intramedullary nailing (IMN), other internal fixation (oIF), revision total knee arthroplasty (rTKA) or non-surgical treatment and vary based on fracture site.
Aim: To report contemporary treatment options and assess risk and type of reoperation according to fracture site.
Materials and Methods: A nationwide cohort study based on register data from 1997 to 2022. Cruciate retaining or posterior stabilized primary TKA were identified from the Danish Knee Arthroplasty Register (DKR). Subsequent PPKFs, fracture treatments and later reoperations were identified through ICD-10 diagnosis and procedure codes in the Danish National Patient Register, or indications for rTKA in the DKR. The sensitivity of rTKA as treatment for PPKF was low and was reported, but not included in further analysis.
Results: We included 1,692 PPKFs (1,337 femoral, 203 patella, 152 tibial). Femoral PPKFs were treated non-operatively (16%), with rTKA (2%), oIF (4%), plate (61%) or IMN (17%). The two-year risk of reoperation was 13% (95% CI: 9-18) after non-operatively treatment, 19% (11-31) after oIF, 18% (15-21) after plate and 18% (13-23) after IMN. Patella PPKFs were treated non-operatively (69%), with rTKA (6%) or oIF (25%). The two- year risk of reoperation was 9% (5-15) after non- operatively treatment and 53% (34-92) after oIF. Tibial PPKFs were treated non-operatively (39%), with rTKA (3%), oIF (33%) or with plate (25%), oIF (50) and non-operatively (58). The two-year risk of reoperation was 21% (12-34) after non-operatively treatment, 40% (27-54) after oIF and 25% (14-41) after plate.
Interpretation / Conclusion: The treatment of PPKFs differ between fracture sites. Femoral PPKFs were primarily treated with plate and IMN, patella non-operatively or with oIF, and tibia non-operatively, with oIF or plate. The reoperation risk was highest in surgically treated patella and tibial PPKFs.
1. Department of Orthopaedic and traumatology, Odense University Hospital 2. Department of Orthopaedic Surgery and Traumatology, Hospital Lillebaelt, Kolding 3. Department of Orthopaedic Surgery and Traumatology, Rigshospitalet, København
Background: Periprosthetic Knee Fracture (PPKF) following Total Knee Arthroplasty (TKA) can be difficult to treat. Treatment options include plating, intramedullary nailing (IMN), other internal fixation (oIF), revision total knee arthroplasty (rTKA) or non-surgical treatment and vary based on fracture site.
Aim: To report contemporary treatment options and assess risk and type of reoperation according to fracture site.
Materials and Methods: A nationwide cohort study based on register data from 1997 to 2022. Cruciate retaining or posterior stabilized primary TKA were identified from the Danish Knee Arthroplasty Register (DKR). Subsequent PPKFs, fracture treatments and later reoperations were identified through ICD-10 diagnosis and procedure codes in the Danish National Patient Register, or indications for rTKA in the DKR. The sensitivity of rTKA as treatment for PPKF was low and was reported, but not included in further analysis.
Results: We included 1,692 PPKFs (1,337 femoral, 203 patella, 152 tibial). Femoral PPKFs were treated non-operatively (16%), with rTKA (2%), oIF (4%), plate (61%) or IMN (17%). The two-year risk of reoperation was 13% (95% CI: 9-18) after non-operatively treatment, 19% (11-31) after oIF, 18% (15-21) after plate and 18% (13-23) after IMN. Patella PPKFs were treated non-operatively (69%), with rTKA (6%) or oIF (25%). The two- year risk of reoperation was 9% (5-15) after non- operatively treatment and 53% (34-92) after oIF. Tibial PPKFs were treated non-operatively (39%), with rTKA (3%), oIF (33%) or with plate (25%), oIF (50) and non-operatively (58). The two-year risk of reoperation was 21% (12-34) after non-operatively treatment, 40% (27-54) after oIF and 25% (14-41) after plate.
Interpretation / Conclusion: The treatment of PPKFs differ between fracture sites. Femoral PPKFs were primarily treated with plate and IMN, patella non-operatively or with oIF, and tibia non-operatively, with oIF or plate. The reoperation risk was highest in surgically treated patella and tibial PPKFs.
Jens Laigaard1, Lone Nikolajsen2, Saber Muthanna Saber1, Ole Mathiesen3, Troels Haxholdt Lunn4, Martin Lindberg-Larsen5, Søren Overgaard1
1. Dept. of Orthopaedic Surgery, Bispebjerg University Hospital; 2. Dept. of Anaesthesia, Aarhus University Hospital; 3. Dept. of Anaesthesia, Zealand University Hospital, Køge; 4. Dept. of Anaesthesia, Bispebjerg University Hospital; 5. Dept. of Orthopaedic Surgery, Odense University Hospital
Background: Total knee arthroplasty (TKA) is considered safe and effective, but previous studies have found that a considerable proportion of patients suffer from persistent pain after surgery. However, these studies are outdated. We believe contemporary data are required to accurately inform patients about postsurgical risks.
Aim: Thus, we aimed to investigate the satisfaction and incidence of persistent pain after primary TKA for osteoarthritis
Materials and Methods: This was a nationwide cross-sectional survey on pain and satisfaction of unselected patients who underwent primary TKA for osteoarthritis from August to November 2022 (NCT05900791). Patients were identified from the Danish National Patient Register and Danish Knee Arthroplasty register and invited by Digital Post on 2nd November 2023.
Results: We sent survey invitations to 3.085 patients after exclusion of 39 (1%) patients with revision surgery and 29 (1%) patients with bilateral surgery within the inclusion period. The 2.167 (70%) respondents were similar to the non-respondents in terms of age, BMI, and length of surgery, but there was a higher proportion of males among the respondents compared to non-respondents (43% versus 36%). Of the respondents, 544 (25%) had moderate or severe persistent postsurgical pain (NRS=4). Still, 1777 (82%) were ‘satisfied’ or ‘very satisfied’ with the result of surgery and 1844 (87%) were willing to repeat surgery.
Interpretation / Conclusion: Twenty-five percent of Danish patients continue to experience moderate to severe pain one year after TKA. Still, 82% are satisfied with the result of surgery. The incidence of persistent postsurgical pain was slightly higher than found in a systematic review from 2012. This could be due to exclusion of the increasing number of unicompartmental knee arthroplasties, who may have a lower incidence of persistent postsurgical pain.
1. Dept. of Orthopaedic Surgery, Bispebjerg University Hospital; 2. Dept. of Anaesthesia, Aarhus University Hospital; 3. Dept. of Anaesthesia, Zealand University Hospital, Køge; 4. Dept. of Anaesthesia, Bispebjerg University Hospital; 5. Dept. of Orthopaedic Surgery, Odense University Hospital
Background: Total knee arthroplasty (TKA) is considered safe and effective, but previous studies have found that a considerable proportion of patients suffer from persistent pain after surgery. However, these studies are outdated. We believe contemporary data are required to accurately inform patients about postsurgical risks.
Aim: Thus, we aimed to investigate the satisfaction and incidence of persistent pain after primary TKA for osteoarthritis
Materials and Methods: This was a nationwide cross-sectional survey on pain and satisfaction of unselected patients who underwent primary TKA for osteoarthritis from August to November 2022 (NCT05900791). Patients were identified from the Danish National Patient Register and Danish Knee Arthroplasty register and invited by Digital Post on 2nd November 2023.
Results: We sent survey invitations to 3.085 patients after exclusion of 39 (1%) patients with revision surgery and 29 (1%) patients with bilateral surgery within the inclusion period. The 2.167 (70%) respondents were similar to the non-respondents in terms of age, BMI, and length of surgery, but there was a higher proportion of males among the respondents compared to non-respondents (43% versus 36%). Of the respondents, 544 (25%) had moderate or severe persistent postsurgical pain (NRS=4). Still, 1777 (82%) were ‘satisfied’ or ‘very satisfied’ with the result of surgery and 1844 (87%) were willing to repeat surgery.
Interpretation / Conclusion: Twenty-five percent of Danish patients continue to experience moderate to severe pain one year after TKA. Still, 82% are satisfied with the result of surgery. The incidence of persistent postsurgical pain was slightly higher than found in a systematic review from 2012. This could be due to exclusion of the increasing number of unicompartmental knee arthroplasties, who may have a lower incidence of persistent postsurgical pain.
Nicolai Kjældgaard Kristensen1,2,3, Laurens Manning4,5, Jeppe Lange 2,3, Joshua Saul Davis6,7
1. Center for Planned Surgery, Regional Hospital of Silkeborg, Denmark 2. Department of Orthopedics, Regional Hospital of Horsens, Denmark 3. Department of Clinical Medicine, Aarhus University, Denmark 4. Medical School, University of Western Australia 5. Department of Infectious Diseases, Fiona Stanley Hospital, WA, Australia 6. School of Medicine and Public Health, University of Newcastle, Newcastle, NSW, Australia 7. : Infection Research Program, Hunter Medical Research Institute, Newcastle, NSW, Australia
Background: Periprosthetic Joint Infection (PJI) is a devastating complication in hip and knee joint arthroplasty. The "JS BACH" classification system was developed in 2021 to stratify the complexity of PJI and more importantly to act as a tool to guide referral to specialist centers. The "JS BACH" classification has not been validated in an external cohort.
Aim: This study aimed to externally validate the JS-BACH classification, using a large prospective cohort from Australia and New Zealand.
Materials and Methods: We applied the JS-BACH classification to the Prosthetic Joint Infection in Australia and New Zealand Observational (PIANO) cohort. This prospective study of newly diagnosed PJI collected 2-year outcome data from 653 participants enrolled from 27 hospitals The definition of PJI treatment failure at 24 months was any of the following: death, clinical or microbiological signs of infection; destination prosthesis removed, or ongoing antibiotic use.
Results: Individual cases were classified as per JS-BACH into "1 - uncomplicated" (n=268), "2 - complex" (n=330), and "3 - limited options" (n=55). This cohort were similar to the original JS-BACH population in terms of baseline characteristics. However, there was a difference in complexity, with more DAIR procedures, fewer revision procedures, and a higher proportion of uncomplicated patients in the PIANO cohort. The risk of treatment failure correlated strongly with JS-BACH category, with odds ratio (95% CI) for category 2 versus 1 of 1.75 (1.24 – 2.47), and for category 3 versus 1 of 7.12 (3.42 – 16.02).
Interpretation / Conclusion: Despite the PIANO study population being less complicated than the original derivation cohort, the JS-BACH classification showed a clear association with treatment failure in this large external cohort.
1. Center for Planned Surgery, Regional Hospital of Silkeborg, Denmark 2. Department of Orthopedics, Regional Hospital of Horsens, Denmark 3. Department of Clinical Medicine, Aarhus University, Denmark 4. Medical School, University of Western Australia 5. Department of Infectious Diseases, Fiona Stanley Hospital, WA, Australia 6. School of Medicine and Public Health, University of Newcastle, Newcastle, NSW, Australia 7. : Infection Research Program, Hunter Medical Research Institute, Newcastle, NSW, Australia
Background: Periprosthetic Joint Infection (PJI) is a devastating complication in hip and knee joint arthroplasty. The "JS BACH" classification system was developed in 2021 to stratify the complexity of PJI and more importantly to act as a tool to guide referral to specialist centers. The "JS BACH" classification has not been validated in an external cohort.
Aim: This study aimed to externally validate the JS-BACH classification, using a large prospective cohort from Australia and New Zealand.
Materials and Methods: We applied the JS-BACH classification to the Prosthetic Joint Infection in Australia and New Zealand Observational (PIANO) cohort. This prospective study of newly diagnosed PJI collected 2-year outcome data from 653 participants enrolled from 27 hospitals The definition of PJI treatment failure at 24 months was any of the following: death, clinical or microbiological signs of infection; destination prosthesis removed, or ongoing antibiotic use.
Results: Individual cases were classified as per JS-BACH into "1 - uncomplicated" (n=268), "2 - complex" (n=330), and "3 - limited options" (n=55). This cohort were similar to the original JS-BACH population in terms of baseline characteristics. However, there was a difference in complexity, with more DAIR procedures, fewer revision procedures, and a higher proportion of uncomplicated patients in the PIANO cohort. The risk of treatment failure correlated strongly with JS-BACH category, with odds ratio (95% CI) for category 2 versus 1 of 1.75 (1.24 – 2.47), and for category 3 versus 1 of 7.12 (3.42 – 16.02).
Interpretation / Conclusion: Despite the PIANO study population being less complicated than the original derivation cohort, the JS-BACH classification showed a clear association with treatment failure in this large external cohort.
Mette Jertrum Hansen1,2, Mette Garval1, Charlotte Runge1,2, Jeppe Lange2,3, Søren T. Skou4,5, Nicolai Kjældgaard Kristensen1,2,3
1. University Clinic for Orthopaedic Pathways (UCOP), Elective Surgery Centre, Silkeborg Regional Hospital. 2. Department of Clinical Medicine, Aarhus University. 3. Department of Orthopedic Surgery, Horsens Regional Hospital. 4. Research Unit for Musculoskeletal Function and Physiotherapy, University of Southern Denmark. 5. The Research and Implementation Unit PROgrez, Næstved-Slagelse-Ringsted Hospitals.
Background: Research has shown that up to one-in-five patients use opioids for three months or more after total knee arthroplasty (TKA). Long-term opioid use increases the risk of dependence and a complicated recovery. The reason for patient-reported opioid use after knee arthroplasty is not previously evaluated.
Aim: To evaluate the prevalence of patient-reported opioid use and the reason for use 12 months after primary knee arthroplasty among Danish patients.
Materials and Methods: We consecutively included 1225 patients undergoing primary TKA or unicompartmental knee arthroplasty (UKA, n = 200) at Silkeborg Regional Hospital from 2018 to 2020. Prior to surgery and at 12-month follow-up, patients reported their use of opioids using a study specific questionnaire. The cohort was divided into three exposure groups (daily opioid use, non-daily opioid use and no opioid use). The primary outcome was patient-reported opioid use 12 months after surgery, and secondary outcome was patient-reported reason for opioid use.
Results: In total, 996 TKA patients (97 %) completed baseline questionnaire about use of opioids; 13.3 % [95 %- CI: 11.2;15.6] reported a preoperative daily opioid use. 797 patients (80 %) completed 12-month follow-up; 4.9 % [95%-CI: 3.5;6.7] reported a daily opioid use, whereof 61.5 % [95%-CI: 44.7;76.2] reported the reason for the daily opioid use as related to pain in the prosthetic knee. Patients with preoperative daily opioid use had a significantly higher risk of opioid use 12 months after surgery (29.7 %, [95%-CI: 21.2;39.7]) compared to patients with no preoperative opioid use, risk difference = 28.8 % [19.8;37.7]. 199 UKA patients (99 %) completed baseline questionnaire; 8.0 % [4.8;13.0] reported a preoperative daily opioid use. 160 patients (80 %) completed 12-month follow-up; 5 patients (3.5 % [95 %-CI: 1.2;7.5]) reported a daily opioid use; 4 with a preoperative daily opioid use and 1 with a preoperative non-daily opioid use.
Interpretation / Conclusion: There is a low risk of daily opioid use caused by pain in the prosthetic knee 12 months after primary knee arthroplasty. Preoperative daily opioid use, compared to no opioid use, has an absolute increase in the risk of daily opioid use 12 months after TKA of 29 %.
1. University Clinic for Orthopaedic Pathways (UCOP), Elective Surgery Centre, Silkeborg Regional Hospital. 2. Department of Clinical Medicine, Aarhus University. 3. Department of Orthopedic Surgery, Horsens Regional Hospital. 4. Research Unit for Musculoskeletal Function and Physiotherapy, University of Southern Denmark. 5. The Research and Implementation Unit PROgrez, Næstved-Slagelse-Ringsted Hospitals.
Background: Research has shown that up to one-in-five patients use opioids for three months or more after total knee arthroplasty (TKA). Long-term opioid use increases the risk of dependence and a complicated recovery. The reason for patient-reported opioid use after knee arthroplasty is not previously evaluated.
Aim: To evaluate the prevalence of patient-reported opioid use and the reason for use 12 months after primary knee arthroplasty among Danish patients.
Materials and Methods: We consecutively included 1225 patients undergoing primary TKA or unicompartmental knee arthroplasty (UKA, n = 200) at Silkeborg Regional Hospital from 2018 to 2020. Prior to surgery and at 12-month follow-up, patients reported their use of opioids using a study specific questionnaire. The cohort was divided into three exposure groups (daily opioid use, non-daily opioid use and no opioid use). The primary outcome was patient-reported opioid use 12 months after surgery, and secondary outcome was patient-reported reason for opioid use.
Results: In total, 996 TKA patients (97 %) completed baseline questionnaire about use of opioids; 13.3 % [95 %- CI: 11.2;15.6] reported a preoperative daily opioid use. 797 patients (80 %) completed 12-month follow-up; 4.9 % [95%-CI: 3.5;6.7] reported a daily opioid use, whereof 61.5 % [95%-CI: 44.7;76.2] reported the reason for the daily opioid use as related to pain in the prosthetic knee. Patients with preoperative daily opioid use had a significantly higher risk of opioid use 12 months after surgery (29.7 %, [95%-CI: 21.2;39.7]) compared to patients with no preoperative opioid use, risk difference = 28.8 % [19.8;37.7]. 199 UKA patients (99 %) completed baseline questionnaire; 8.0 % [4.8;13.0] reported a preoperative daily opioid use. 160 patients (80 %) completed 12-month follow-up; 5 patients (3.5 % [95 %-CI: 1.2;7.5]) reported a daily opioid use; 4 with a preoperative daily opioid use and 1 with a preoperative non-daily opioid use.
Interpretation / Conclusion: There is a low risk of daily opioid use caused by pain in the prosthetic knee 12 months after primary knee arthroplasty. Preoperative daily opioid use, compared to no opioid use, has an absolute increase in the risk of daily opioid use 12 months after TKA of 29 %.