Session 3: Knee arthroplasty
13. November
09:00 - 10:30
Lokale: Skovbrynet
Chair: Klaus Poulsen & Müjgan Yilmaz
Emil Toft Petersen1,2,3, Carl Christian Holkgaard Burvil1,3, Karina Nørgaard Linde1,2,3, Søren Rytter1,2,3, Daan Koppens1,2,3, Jesper Dalsgaard4, Torben Bæk Hansen3,4, Maiken Stilling1,2,3
1. AutoRSA Research Group, Orthopaedic Research Unit, Aarhus University Hospital, Aarhus N, Denmark; 2. Department of Orthopedic Surgery, Aarhus University Hospital, Aarhus N, Denmark; 3. Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; 4. Department of Orthopedics, Gødstrup Hospital, Gødstrup, Denmark;
Background: The Persona Total Knee System, designed anatomically in multiple sizes, aims to improve patient fit and patient satisfaction. The system provides a classic symmetric cruciate-retaining (CR) polyethylene insert and an asymmetric medial congruent (MC) polyethylene insert. The MC insert's enhanced medial conformity, featuring a taller anterior lip and a posteriorly positioned femoral component dwell point, may elevate arthroplasty constraints, particularly affecting femoral component fixation.
Aim: To evaluate the impact of CR and MC polyethylene inserts on femoral and tibial component migration in the cemented Persona Total Knee System.
Materials and Methods: A study involved 66 knee osteoarthritis patients undergoing surgery with the cemented Persona system, randomized to CR or MC inserts. Femoral and tibial component migration was assessed using static radiostereometric analysis, with the first stereo-radiograph taken supine on the first postoperative day (baseline) and again at 3-, 12-, and 24-month follow-up. Migrations were measured in six degrees of freedom and as maximum total point motion (MTPM).
Results: The mean MTPM for the tibial component was similar with 0.92 mm (CI95% 0.68; 1.15) for the CR group and 0.96 mm (CI95% 0.72; 1.21) for the MC group at 24 months follow-up. Additionally, the tibial component migration pattern in all degrees of freedom (signed migrations) was similar for the MC and the CR group throughout 24 months of follow-up (p>0.09). The mean MTPM for the femoral component was similar with 1.39 mm (CI95% 1.12; 1.66) for the CR group and 1.17 mm (CI95% 0.90; 1.44) for the MC group at 24 months follow-up. The signed migration pattern of the femoral components showed 0.18 mm (95% CI: 0.03; 0.32) and 0.20 mm (95% CI: 0.01; 0.39) more medial migration for the patients with the MC than the CR group at 3 and 12 months, respectively.
Interpretation / Conclusion: The tibial components had good fixation regardless of the type of polyethylene inserts (CR or MC). However, the femoral components in the MC group migrated slightly more medially than the CR group up to one year postoperatively. This suggests that the enhanced constraint on the femoral component due to the polyethylene design could impact its fixation.
1. AutoRSA Research Group, Orthopaedic Research Unit, Aarhus University Hospital, Aarhus N, Denmark; 2. Department of Orthopedic Surgery, Aarhus University Hospital, Aarhus N, Denmark; 3. Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; 4. Department of Orthopedics, Gødstrup Hospital, Gødstrup, Denmark;
Background: The Persona Total Knee System, designed anatomically in multiple sizes, aims to improve patient fit and patient satisfaction. The system provides a classic symmetric cruciate-retaining (CR) polyethylene insert and an asymmetric medial congruent (MC) polyethylene insert. The MC insert's enhanced medial conformity, featuring a taller anterior lip and a posteriorly positioned femoral component dwell point, may elevate arthroplasty constraints, particularly affecting femoral component fixation.
Aim: To evaluate the impact of CR and MC polyethylene inserts on femoral and tibial component migration in the cemented Persona Total Knee System.
Materials and Methods: A study involved 66 knee osteoarthritis patients undergoing surgery with the cemented Persona system, randomized to CR or MC inserts. Femoral and tibial component migration was assessed using static radiostereometric analysis, with the first stereo-radiograph taken supine on the first postoperative day (baseline) and again at 3-, 12-, and 24-month follow-up. Migrations were measured in six degrees of freedom and as maximum total point motion (MTPM).
Results: The mean MTPM for the tibial component was similar with 0.92 mm (CI95% 0.68; 1.15) for the CR group and 0.96 mm (CI95% 0.72; 1.21) for the MC group at 24 months follow-up. Additionally, the tibial component migration pattern in all degrees of freedom (signed migrations) was similar for the MC and the CR group throughout 24 months of follow-up (p>0.09). The mean MTPM for the femoral component was similar with 1.39 mm (CI95% 1.12; 1.66) for the CR group and 1.17 mm (CI95% 0.90; 1.44) for the MC group at 24 months follow-up. The signed migration pattern of the femoral components showed 0.18 mm (95% CI: 0.03; 0.32) and 0.20 mm (95% CI: 0.01; 0.39) more medial migration for the patients with the MC than the CR group at 3 and 12 months, respectively.
Interpretation / Conclusion: The tibial components had good fixation regardless of the type of polyethylene inserts (CR or MC). However, the femoral components in the MC group migrated slightly more medially than the CR group up to one year postoperatively. This suggests that the enhanced constraint on the femoral component due to the polyethylene design could impact its fixation.
Karina Nørgaard Linde1, 2, Bente Langdahl1, 3, Søren Rytter1, 2, Maiken Stilling1, 2
1. Department of Orthopaedics, Aarhus University Hospital; 2. Department of Clinical Medicine, Aarhus University; 3. Department of Endocrinology and Clinical Medicine, Aarhus University Hospital
Background: Aseptic loosening of a knee arthroplasty (KA) is a major cause of revision surgery. We hypothesized that systemic low bone mineral density (BMD) is a risk factor for aseptic loosening of tibial implants.
Aim: To study the association between BMD and tibial implant migration.
Materials and Methods: A prospective clinical cohort study in 364 patients (364 knees) operated at Aarhus University Hospital between April 2014 and March 2016 with a unicompartmental KA or a total KA. Cementless tibial implants were used in 193 patients and 171 patients received a cemented implant. Preoperatively, patients were examined with DXA of the spine and hips (the lowest T- score was used). Postoperatively, and at 1 and 2 years follow-up, patients were examined with radiostereometric analysis (RSA). The primary outcome was tibial implant migration measured by RSA. Migration was evaluated by Maximum Total Point Motion (MTPM). Continuous migrating implants were defined as MTPM>0.2 mm between 1 and 2 years of follow-up and stable implants as MTPM<0.2 mm between 1 and 2 years of follow-up. Analyses were stratified by cemented and cementless implants.
Results: For cementless tibial implants, 31 patients had continuous migration and 162 had stable migration. Implants with continuous migration had a lower mean preoperative T- score (-0.98 (CI: -1.31; -0.65)) than stable implants (-0.50 (CI: -0.70; -0.31), p=0.046. A high T-score (OR 0.71 (CI: 0.50; 1.00), p=0.048) decreased the risk of continuous migration (adjusted for sex, age, and BMI: OR 0.68, CI: 0.46; 1.00, p=0.052). For cemented tibial implants, 36 patients had continuous migration and 135 had stable migration. The mean difference in the preoperative T-score between groups was -0.10 (CI: -0.67; 0.46), p=0.71. The T-score did not decrease the risk of continuous migration (adjusted for sex, age, and BMI: OR 0.99 (CI: 0.72; 1.38), p=0.96).
Interpretation / Conclusion: A higher preoperative T-score decreased the risk of continuous migration of cementless tibial implants but not for cemented implants. Results indicate that patients with lower BMD may benefit from a cemented implant or that optimizing the BMD (e.g. by antiresorptives) before surgery could prevent implant migration and subsequent loosening.
1. Department of Orthopaedics, Aarhus University Hospital; 2. Department of Clinical Medicine, Aarhus University; 3. Department of Endocrinology and Clinical Medicine, Aarhus University Hospital
Background: Aseptic loosening of a knee arthroplasty (KA) is a major cause of revision surgery. We hypothesized that systemic low bone mineral density (BMD) is a risk factor for aseptic loosening of tibial implants.
Aim: To study the association between BMD and tibial implant migration.
Materials and Methods: A prospective clinical cohort study in 364 patients (364 knees) operated at Aarhus University Hospital between April 2014 and March 2016 with a unicompartmental KA or a total KA. Cementless tibial implants were used in 193 patients and 171 patients received a cemented implant. Preoperatively, patients were examined with DXA of the spine and hips (the lowest T- score was used). Postoperatively, and at 1 and 2 years follow-up, patients were examined with radiostereometric analysis (RSA). The primary outcome was tibial implant migration measured by RSA. Migration was evaluated by Maximum Total Point Motion (MTPM). Continuous migrating implants were defined as MTPM>0.2 mm between 1 and 2 years of follow-up and stable implants as MTPM<0.2 mm between 1 and 2 years of follow-up. Analyses were stratified by cemented and cementless implants.
Results: For cementless tibial implants, 31 patients had continuous migration and 162 had stable migration. Implants with continuous migration had a lower mean preoperative T- score (-0.98 (CI: -1.31; -0.65)) than stable implants (-0.50 (CI: -0.70; -0.31), p=0.046. A high T-score (OR 0.71 (CI: 0.50; 1.00), p=0.048) decreased the risk of continuous migration (adjusted for sex, age, and BMI: OR 0.68, CI: 0.46; 1.00, p=0.052). For cemented tibial implants, 36 patients had continuous migration and 135 had stable migration. The mean difference in the preoperative T-score between groups was -0.10 (CI: -0.67; 0.46), p=0.71. The T-score did not decrease the risk of continuous migration (adjusted for sex, age, and BMI: OR 0.99 (CI: 0.72; 1.38), p=0.96).
Interpretation / Conclusion: A higher preoperative T-score decreased the risk of continuous migration of cementless tibial implants but not for cemented implants. Results indicate that patients with lower BMD may benefit from a cemented implant or that optimizing the BMD (e.g. by antiresorptives) before surgery could prevent implant migration and subsequent loosening.
Kristian R. L. Mortensen1, Lina Holm Ingelsrud1, Omar Muharemovic2, Morten G. Thomsen3, Anders Troelsen1
1. Clinical Orthopaedic Research Hvidovre, Department of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Denmark 2. Functional and Diagnostic Imaging, Copenhagen University Hospital Hvidovre, Denmark 3. Department of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Denmark
Background: Bi-cruciate retaining Total Knee Arthroplasty (TKA) proposedly provides stability in the implanted knee due to retainment of the ligaments. However, questions about the treatment quality with this implant led us to compare fixation, knee symptoms and complications to a traditional Cruciate Retaining (CR) design 2 years post-surgery.
Aim: The purpose of this post-analysis was to compare fixation of the Vanguard XP (XP) to a CR design, while also comparing knee function, pain and number of complications 5 years post-surgery.
Materials and Methods: 50 patients with primary knee osteoarthritis were included in this single-blinded RCT and randomized to an XP or a CR TKA. Follow-up visits were 3 months, 1,2 and 5 years post-surgery. Primary outcome was Tibia Maximum Total Point Motion (MTPM) measured with Radiostereometric Analysis (RSA). Secondary outcomes were knee function and pain, measured with the Oxford Knee Score (OKS) and number of treatment-related complications. We analyzed OKS as time-weighted average (TWA) of the change from baseline in OKS and tested differences in the outcomes with a welch t-test.
Results: 43 patients (86%, XP: 21, CR: 22) met for 5 year follow-up, MTPM was available for 42 patients (XP: 20, CR:22). Mean 5y MTPM was 0.91 [95%CI: 0.58 – 1.24] mm in the XP group and 0.71 [95%CI 0.51 – 0.91] mm in the CR group. The difference was 0.2 [95%CI -0.58 – 0.18] mm, and not statistically significant (p-value = 0.29). Mean TWA of OKS change in OKS was 15.8 [95%CI 11.8 – 19.8] in the XP group and 16.1 [95%CI 13.8 – 18.4] in the CR group. The difference was 0.3 [95%CI -4.2 – 4.9] and not statistically significant (p-value = 0.87). 2 complications were registered from 2 to 5 year follow-up in 1 patient (XP group), who underwent arthroscopic synovectomy and was revised 3 months later. Sum of complications was 7 (XP) vs. 0 (CR) (revisions: 2 (XP) vs. 0 (CR)) 5 years post-operatively.
Interpretation / Conclusion: We found no differences between patients operated with XP or CR implants with regards to tibia fixation or knee function and pain 5 years post-surgery. 2 more complications, of which 1 was a revision, were registered in the XP-group, highlighting the potential learning curve related to bi-cruciate retaining TKA.
1. Clinical Orthopaedic Research Hvidovre, Department of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Denmark 2. Functional and Diagnostic Imaging, Copenhagen University Hospital Hvidovre, Denmark 3. Department of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Denmark
Background: Bi-cruciate retaining Total Knee Arthroplasty (TKA) proposedly provides stability in the implanted knee due to retainment of the ligaments. However, questions about the treatment quality with this implant led us to compare fixation, knee symptoms and complications to a traditional Cruciate Retaining (CR) design 2 years post-surgery.
Aim: The purpose of this post-analysis was to compare fixation of the Vanguard XP (XP) to a CR design, while also comparing knee function, pain and number of complications 5 years post-surgery.
Materials and Methods: 50 patients with primary knee osteoarthritis were included in this single-blinded RCT and randomized to an XP or a CR TKA. Follow-up visits were 3 months, 1,2 and 5 years post-surgery. Primary outcome was Tibia Maximum Total Point Motion (MTPM) measured with Radiostereometric Analysis (RSA). Secondary outcomes were knee function and pain, measured with the Oxford Knee Score (OKS) and number of treatment-related complications. We analyzed OKS as time-weighted average (TWA) of the change from baseline in OKS and tested differences in the outcomes with a welch t-test.
Results: 43 patients (86%, XP: 21, CR: 22) met for 5 year follow-up, MTPM was available for 42 patients (XP: 20, CR:22). Mean 5y MTPM was 0.91 [95%CI: 0.58 – 1.24] mm in the XP group and 0.71 [95%CI 0.51 – 0.91] mm in the CR group. The difference was 0.2 [95%CI -0.58 – 0.18] mm, and not statistically significant (p-value = 0.29). Mean TWA of OKS change in OKS was 15.8 [95%CI 11.8 – 19.8] in the XP group and 16.1 [95%CI 13.8 – 18.4] in the CR group. The difference was 0.3 [95%CI -4.2 – 4.9] and not statistically significant (p-value = 0.87). 2 complications were registered from 2 to 5 year follow-up in 1 patient (XP group), who underwent arthroscopic synovectomy and was revised 3 months later. Sum of complications was 7 (XP) vs. 0 (CR) (revisions: 2 (XP) vs. 0 (CR)) 5 years post-operatively.
Interpretation / Conclusion: We found no differences between patients operated with XP or CR implants with regards to tibia fixation or knee function and pain 5 years post-surgery. 2 more complications, of which 1 was a revision, were registered in the XP-group, highlighting the potential learning curve related to bi-cruciate retaining TKA.
Stian Langgård Jørgensen1,2,3, Per Aagaard4, Marie Bagger Bohn2.3, Peter Hansen5, Per Møller Hansen5, Carsten Holm6, Louise Mortensen7, Mette Garval6, Lisa Urup Tønning3,8, Inger Mechlenburg3,8,9,10
1. Department of Occupational and Physical Therapy. Horsens Regional Hospital, Denmark; 2. H-HIP, Department of Orthopaedic Surgery, Horsens Regional Hospital, Denmark; 3. Department of Clinical Medicine, Aarhus University, Denmark 4. Department of Sports Science and Clinical Biomechanics, University of Southern Denmark; 5. Department of Orthopaedic Surgery, Horsens Regional Hospital, Denmark; 6. Elective Surgery Centre, Silkeborg Regional Hospital; University Research Clinic for Patient Centred Elective Orthopaedic Pathways Silkeborg Regional Hospital; 7. Department of Occupational and Physical Therapy, Aarhus University Hospital; 8. Department of Orthopaedic Surgery, Aarhus University Hospital, Denmark; 9. Department of Public Health, Aarhus University, Denmark; 10. Exercise Biology, Department of Public Health, Section of Sports Science, Aarhus University
Background: Following TKA, patients demonstrate persistent deficits in physical function compared with healthy aged-matched peers. Purpose: To examine the efficacy of preoperative low-load blood-flow restricted exercise (BFR-RT) on physical function, leg muscle strength and self-reported outcomes post-TKA compared with standard preoperative care.
Aim: To examine the efficacy of preoperative low-load blood-flow restricted exercise (BFR-RT) on physical function, leg muscle strength and self- reported outcomes post-TKA compared with standard preoperative care.
Materials and Methods: A randomized controlled trial. Eighty-six patients scheduled for TKA were randomized to 8 weeks preoperative BFR-RT 3x/week or preoperative usual care. Outcomes were collected at baseline, before surgery, and three months after surgery on the 30-s sit-to-stand (30STS), Timed Up & Go (TUG), 40 meter fast paced walk test (40mFWT), 1 repetition maximum (RM) leg press and knee extension, maximal isometric knee extension (knee extensor MVC) and flexion (knee flexor MVC), and the Knee-injury and Osteoarthritis Outcome Score (KOOS) subscales Pain, Symptoms, Activities of Daily Living, Sport&Recreation, and Quality of Life.
Results: Intention-to-treat analysis found no significant between-group changes from baseline to three months postoperatively on 30STS (0.01[95%CI- 1.7;1.7]repetitions), TUG (0.1[-0.8;1.0]seconds), or 40mFWT (0.1[-2.4;2.5]seconds). Significant changes were observed for 1RM leg press strength on the affected (-16.3[-26.2;-6.4]kg) and non-affected leg (-13.2[-26.3;0.00]kg), and 1RM knee extensor strength (-4.7[-8.4;-1.0]kg) three months postoperatively favoring BFR-RT. Significant differences in knee extensor MVC on the affected leg was observed three months postoperatively (-0.51[-0.92; -0.10]Nm/kg) favoring BFR-RT. No changes were observed for KOOS subscales.
Interpretation / Conclusion: Eight weeks of preoperative BFR-RT yielded no superior effects compared with usual preoperative care on physical function or patient-reported outcomes three months after surgery. BFR-RT elicited significant gains in lower limb strength persisting up to three months after surgery.
1. Department of Occupational and Physical Therapy. Horsens Regional Hospital, Denmark; 2. H-HIP, Department of Orthopaedic Surgery, Horsens Regional Hospital, Denmark; 3. Department of Clinical Medicine, Aarhus University, Denmark 4. Department of Sports Science and Clinical Biomechanics, University of Southern Denmark; 5. Department of Orthopaedic Surgery, Horsens Regional Hospital, Denmark; 6. Elective Surgery Centre, Silkeborg Regional Hospital; University Research Clinic for Patient Centred Elective Orthopaedic Pathways Silkeborg Regional Hospital; 7. Department of Occupational and Physical Therapy, Aarhus University Hospital; 8. Department of Orthopaedic Surgery, Aarhus University Hospital, Denmark; 9. Department of Public Health, Aarhus University, Denmark; 10. Exercise Biology, Department of Public Health, Section of Sports Science, Aarhus University
Background: Following TKA, patients demonstrate persistent deficits in physical function compared with healthy aged-matched peers. Purpose: To examine the efficacy of preoperative low-load blood-flow restricted exercise (BFR-RT) on physical function, leg muscle strength and self-reported outcomes post-TKA compared with standard preoperative care.
Aim: To examine the efficacy of preoperative low-load blood-flow restricted exercise (BFR-RT) on physical function, leg muscle strength and self- reported outcomes post-TKA compared with standard preoperative care.
Materials and Methods: A randomized controlled trial. Eighty-six patients scheduled for TKA were randomized to 8 weeks preoperative BFR-RT 3x/week or preoperative usual care. Outcomes were collected at baseline, before surgery, and three months after surgery on the 30-s sit-to-stand (30STS), Timed Up & Go (TUG), 40 meter fast paced walk test (40mFWT), 1 repetition maximum (RM) leg press and knee extension, maximal isometric knee extension (knee extensor MVC) and flexion (knee flexor MVC), and the Knee-injury and Osteoarthritis Outcome Score (KOOS) subscales Pain, Symptoms, Activities of Daily Living, Sport&Recreation, and Quality of Life.
Results: Intention-to-treat analysis found no significant between-group changes from baseline to three months postoperatively on 30STS (0.01[95%CI- 1.7;1.7]repetitions), TUG (0.1[-0.8;1.0]seconds), or 40mFWT (0.1[-2.4;2.5]seconds). Significant changes were observed for 1RM leg press strength on the affected (-16.3[-26.2;-6.4]kg) and non-affected leg (-13.2[-26.3;0.00]kg), and 1RM knee extensor strength (-4.7[-8.4;-1.0]kg) three months postoperatively favoring BFR-RT. Significant differences in knee extensor MVC on the affected leg was observed three months postoperatively (-0.51[-0.92; -0.10]Nm/kg) favoring BFR-RT. No changes were observed for KOOS subscales.
Interpretation / Conclusion: Eight weeks of preoperative BFR-RT yielded no superior effects compared with usual preoperative care on physical function or patient-reported outcomes three months after surgery. BFR-RT elicited significant gains in lower limb strength persisting up to three months after surgery.
Jonathan Hugo Jürgens-Lahnstein1, 2, 3, Anders Odgaard4, Søren Rytter1, 2, 3, Frank Madsen1, Lone Rømer, Per Wagner Kristensen6, Kjeld Søballe1, 2, Maiken Stilling1, 2, 3
1. Department of Orthopaedic Surgery, Aarhus University Hospital, Denmark; 2. AutoRSA Research Group, Aarhus University Hospital, Denmark; 3. Department of Clincal Medicine, Aarhus University, Denmark; 4. Department of Orthopaedic Surgery, Gentofte Hospital, Denmark; 5. Department of Radiology, Aarhus University Hospital, Denmark; 6. Department of Orthopaedic Surgery, Vejle Hospital, Denmark
Background: In recent years, the preferred fixation method for unicompartmental knee arthroplasty (UKA) has changed from cemented to cementless.
Aim: This study compares the 5-year component fixation and the 10-year clinical outcomes of cemented (C) and cementless (CL) UKA.
Materials and Methods: 79 patients (48 men) were randomly allocated to surgery with cementless (CL) hydroxyapatite-coated (n=25) or cemented (C) (n=54) Oxford® Partial Knee tibial trays (ZimmerBiomet) in a multicenter study. Femoral components were either single- pegged or double-pegged in the C group and double-pegged in the CL group. Refobacin bone cement was used. Evaluation of implant migration, and clinical outcomes (OKS and KOOS) was performed at 6 weeks, 3 and 6 months, and 1, 2, and 5 years. At 10 years clinical results were evaluated with the KOOS and OKS.
Results: Tibial component migration up to 5 years was presented at a previous DOS conference (2017). 5-year migration showed CL UKA migrated initially but stabilized at 6 months. Between 2- and 5-years follow-up CL fixation was as good as C fixation. Clinical outcomes at 5 years, displayed mean OKS of 39 (12-48), which was similar between groups (p=0.47), and with comparable improvement from baseline (p=0.18). 91.6% with C and 94.1% with CL were satisfied with the result (p=0.91). OKS did not differ significantly between the CL and C group at 10-years follow-up. KOOS at 10-years, revealed a statistically significant difference for the following KOOS sub-scores between C and CL favoring the C tibial tray: ADL (8.97, 95%CI: 0.51 - 17.42; p=0.04), pain (9.56, 95%CI: 0.67 - 18.46; p=0.04), QOL (16.29, 95%CI: 5.04 - 27.54; p=0.01) and SportRec (18.30, 95%CI: 1.35 – 35.24; p=0.03).
Interpretation / Conclusion: CL UKA migrated initially but stabilized at 6 months. Between 2- and 5-years follow-up CL fixation was as good as C fixation. There was no difference in OKS or KOOS total score between the CL and C group during 10 years-follow up. At 10 years follow-up KOOS subscores favored the C group.
1. Department of Orthopaedic Surgery, Aarhus University Hospital, Denmark; 2. AutoRSA Research Group, Aarhus University Hospital, Denmark; 3. Department of Clincal Medicine, Aarhus University, Denmark; 4. Department of Orthopaedic Surgery, Gentofte Hospital, Denmark; 5. Department of Radiology, Aarhus University Hospital, Denmark; 6. Department of Orthopaedic Surgery, Vejle Hospital, Denmark
Background: In recent years, the preferred fixation method for unicompartmental knee arthroplasty (UKA) has changed from cemented to cementless.
Aim: This study compares the 5-year component fixation and the 10-year clinical outcomes of cemented (C) and cementless (CL) UKA.
Materials and Methods: 79 patients (48 men) were randomly allocated to surgery with cementless (CL) hydroxyapatite-coated (n=25) or cemented (C) (n=54) Oxford® Partial Knee tibial trays (ZimmerBiomet) in a multicenter study. Femoral components were either single- pegged or double-pegged in the C group and double-pegged in the CL group. Refobacin bone cement was used. Evaluation of implant migration, and clinical outcomes (OKS and KOOS) was performed at 6 weeks, 3 and 6 months, and 1, 2, and 5 years. At 10 years clinical results were evaluated with the KOOS and OKS.
Results: Tibial component migration up to 5 years was presented at a previous DOS conference (2017). 5-year migration showed CL UKA migrated initially but stabilized at 6 months. Between 2- and 5-years follow-up CL fixation was as good as C fixation. Clinical outcomes at 5 years, displayed mean OKS of 39 (12-48), which was similar between groups (p=0.47), and with comparable improvement from baseline (p=0.18). 91.6% with C and 94.1% with CL were satisfied with the result (p=0.91). OKS did not differ significantly between the CL and C group at 10-years follow-up. KOOS at 10-years, revealed a statistically significant difference for the following KOOS sub-scores between C and CL favoring the C tibial tray: ADL (8.97, 95%CI: 0.51 - 17.42; p=0.04), pain (9.56, 95%CI: 0.67 - 18.46; p=0.04), QOL (16.29, 95%CI: 5.04 - 27.54; p=0.01) and SportRec (18.30, 95%CI: 1.35 – 35.24; p=0.03).
Interpretation / Conclusion: CL UKA migrated initially but stabilized at 6 months. Between 2- and 5-years follow-up CL fixation was as good as C fixation. There was no difference in OKS or KOOS total score between the CL and C group during 10 years-follow up. At 10 years follow-up KOOS subscores favored the C group.
Oddrún Danielsen1,2, Kirill Gromov1,3, Claus Varnum1,4, Thomas Jakobsen1,5, Mikkel Rathsach Andersen1,6, Manuel Josef Bieder1,7, Christoffer Calov Jørgensen1,8, Henrik Kehlet1,9, Martin Lindberg-Larsen1,2
1. Center for Fast-track Hip and Knee Replacement, Denmark 2. Dept. of Orthopaedic Surgery and traumatology, Odense University Hospital and Svendborg 3. Dept. of Orthopaedic Surgery, Hvidovre University Hospital 4. Dept. of Orthopaedic Surgery, Lillebaelt Hospital – Vejle 5. Dept. of Orthopaedic Surgery, Aalborg University Hospital 6. Dept. of Orthopaedic Surgery, Copenhagen University Hospital, Herlev-Gentofte 7. Dept. of Orthopaedic surgery, Næstved, Slagelse and Ringsted Hospitals 8. Dept. of Anaesthesia, Hospital of Northern Zeeland, Hillerød 9. Section of Surgical Pathophysiology, Copenhagen University Hospital, Rigshospitalet
Background: The feasibility of implementing day-case surgery in 20-25% of all primary hip and knee arthroplasty patients in a public multicenter setting is well established. However, there is a lack of documentation regarding patients' perspectives on undergoing day-case procedures, which is essential to support its adoption as a standard of care.
Aim: The aim of this study was to investigate whether patients were willing to repeat being discharged on day of surgery if having a second hip or knee arthroplasty procedure.
Materials and Methods: This is a multicentre prospective consecutive cohort study from 6 public arthroplasty centres with a well-established day-case protocol. The study period was from September 2022 to January 2024. Patients undergoing primary total hip arthroplasty (THA), total knee arthroplasty (TKA) or medial unicompartmental knee arthroplasty (mUKA) were screened for day-case eligibility using well-defined in- and exclusion criteria and discharged when fulfilling predetermined discharge criteria. Day-case patients received a survey 30 days postoperatively with the question: If you were to undergo hip/knee replacement on the opposite side, would you prefer to be discharged on the day of surgery again?
Results: Of 8,843 primary hip and knee arthroplasties registered in the database, 2,002 (23%) were eligible and discharged on day of surgery. Baseline characteristics were comparable across all three arthroplasty groups. The survey response rate was 85%. Overall, 90% (95% CI 88-91%) were willing to repeat discharge on day of surgery. Procedure specific willingness to repeat day-case surgery were 91% (88-93%) after THA, 89% (86-92%) after TKA and 90% (86-92%) after mUKA. Patients unwilling to repeat day-case surgery were more often females (55%) compared to patients willing to repeat day-case surgery (47%), otherwise, the groups were comparable.
Interpretation / Conclusion: A total of 90% of patients discharged on the day of surgery after hip and knee arthroplasty were willing to repeat day-case surgery. While this rate appears acceptable for ongoing implementation, gathering qualitative data from patients unwilling to repeat the process could enhance patient selection and refine the day-case pathway.
1. Center for Fast-track Hip and Knee Replacement, Denmark 2. Dept. of Orthopaedic Surgery and traumatology, Odense University Hospital and Svendborg 3. Dept. of Orthopaedic Surgery, Hvidovre University Hospital 4. Dept. of Orthopaedic Surgery, Lillebaelt Hospital – Vejle 5. Dept. of Orthopaedic Surgery, Aalborg University Hospital 6. Dept. of Orthopaedic Surgery, Copenhagen University Hospital, Herlev-Gentofte 7. Dept. of Orthopaedic surgery, Næstved, Slagelse and Ringsted Hospitals 8. Dept. of Anaesthesia, Hospital of Northern Zeeland, Hillerød 9. Section of Surgical Pathophysiology, Copenhagen University Hospital, Rigshospitalet
Background: The feasibility of implementing day-case surgery in 20-25% of all primary hip and knee arthroplasty patients in a public multicenter setting is well established. However, there is a lack of documentation regarding patients' perspectives on undergoing day-case procedures, which is essential to support its adoption as a standard of care.
Aim: The aim of this study was to investigate whether patients were willing to repeat being discharged on day of surgery if having a second hip or knee arthroplasty procedure.
Materials and Methods: This is a multicentre prospective consecutive cohort study from 6 public arthroplasty centres with a well-established day-case protocol. The study period was from September 2022 to January 2024. Patients undergoing primary total hip arthroplasty (THA), total knee arthroplasty (TKA) or medial unicompartmental knee arthroplasty (mUKA) were screened for day-case eligibility using well-defined in- and exclusion criteria and discharged when fulfilling predetermined discharge criteria. Day-case patients received a survey 30 days postoperatively with the question: If you were to undergo hip/knee replacement on the opposite side, would you prefer to be discharged on the day of surgery again?
Results: Of 8,843 primary hip and knee arthroplasties registered in the database, 2,002 (23%) were eligible and discharged on day of surgery. Baseline characteristics were comparable across all three arthroplasty groups. The survey response rate was 85%. Overall, 90% (95% CI 88-91%) were willing to repeat discharge on day of surgery. Procedure specific willingness to repeat day-case surgery were 91% (88-93%) after THA, 89% (86-92%) after TKA and 90% (86-92%) after mUKA. Patients unwilling to repeat day-case surgery were more often females (55%) compared to patients willing to repeat day-case surgery (47%), otherwise, the groups were comparable.
Interpretation / Conclusion: A total of 90% of patients discharged on the day of surgery after hip and knee arthroplasty were willing to repeat day-case surgery. While this rate appears acceptable for ongoing implementation, gathering qualitative data from patients unwilling to repeat the process could enhance patient selection and refine the day-case pathway.
Tazio Maleitzke1,2,3,4, Sijia Zhou1,2, Alexander Hildebrandt1,2, Ali Mobasheri5,6,7,8, Florian N. Fleckenstein9,10, Nitsan Halevy11, Sven Geissler2,12,13, Georg N. Duda2, Tobias Winkler1,2,12
1. Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Center for Musculoskeletal Surgery, Berlin, Germany 2. Berlin Institute of Health at Charité – Universitätsmedizin Berlin, Julius Wolff Institute, Berlin, Germany 3. Department of Orthopaedic Surgery, Copenhagen University Hospital Amager and Hvidovre, Hvidovre, Denmark 4. Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark 5. Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland 6. Department of Regenerative Medicine, State Research Institute Centre for Innovative Medicine, Vilnius, Lithuania 7. Department of Joint Surgery, First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China 8. World Health Organization Collaborating Center for Public Health Aspects of Musculoskeletal Health and Aging, Université de Liège, Liège, Belgium 9. Department of Diagnostic and Interventional Radiology, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany 10. BIH Charité Clinician Scientist Program, Berlin Institute of Health at Charité – Universitätsmedizin Berlin, BIH Biomedical Innovation Academy, Berlin, Germany 11. Pluri-Biotech Ltd., Haifa, Israel 12. Berlin Institute of Health at Charité - Universitätsmedizin Berlin, BIH Center for Regenerative Therapies (BCRT), Berlin, Germany 13. Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin Center for Advanced Therapies (BeCAT), Berlin, Germany
Background: Despite the increasing global burden of osteoarthritis (OA), no disease modifying drug has yet advanced to market entry. Market approval is often not reached, because preclinical data for novel OA therapeutics can not be reproduced clinically. Among others, this may be due to the choice of the OA model (primary vs. secondary) and the degree of OA addressed (mild to moderate vs. severe) which do often not match in preclinical and clinical studies.
Aim: With this study, we test the safety and efficacy of placenta-derived mesenchymal like stromal cells (PLX-PAD) for the treatment of mild- moderate primary OA in the Dunkin Hartley guinea pig model, as a basis for the PROTO consortium clinical trial.
Materials and Methods: Thirty sex-matched six-month-old Dunkin Hartley guinea pigs were randomized to receive either a single intra-articular injection of (i) PLX- PAD (1 million), (ii) PLX-PAD (2 million), or (iii) phosphate buffered saline (PBS) into the intraarticular space of both knees. All animals underwent in vivo magnetic resonance imaging (MRI) one and six months post-injection. All animals were sacrificed six months post injection, and samples were harvested for histological (OARSI grading), radiological (µ- CT), and molecular (gene and protein) analysis. Here, we present the histological and clinical data available to date.
Results: No swelling, redness or limping were observed for any of the animals regardless of treatment group throughout the study. At six months post injection, PBS treated animals presented signs of severe OA histologically, while PLX-PAD treated animals only showed a mild progression of the disease (PLX-PAD, 1 million, p=0.007; PLX-PAD, 2 million, p=0.066). No animals showed ectopic bone formation or severe synovial infiltration.
Interpretation / Conclusion: These initial histological and clinical results indicate PLX-PAD is biologically active with no local toxicity observed in this model of mild- moderate primary OA compared to placebo. Further evaluation of radiological and molecular data will enable the PROTO consortium (funded by Horizon Europe Grant Nr. 101095635) to translate these preclinical findings into a human phase I/IIa trial, which matches the disease type and severity of the preclinical model.
1. Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Center for Musculoskeletal Surgery, Berlin, Germany 2. Berlin Institute of Health at Charité – Universitätsmedizin Berlin, Julius Wolff Institute, Berlin, Germany 3. Department of Orthopaedic Surgery, Copenhagen University Hospital Amager and Hvidovre, Hvidovre, Denmark 4. Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark 5. Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland 6. Department of Regenerative Medicine, State Research Institute Centre for Innovative Medicine, Vilnius, Lithuania 7. Department of Joint Surgery, First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China 8. World Health Organization Collaborating Center for Public Health Aspects of Musculoskeletal Health and Aging, Université de Liège, Liège, Belgium 9. Department of Diagnostic and Interventional Radiology, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany 10. BIH Charité Clinician Scientist Program, Berlin Institute of Health at Charité – Universitätsmedizin Berlin, BIH Biomedical Innovation Academy, Berlin, Germany 11. Pluri-Biotech Ltd., Haifa, Israel 12. Berlin Institute of Health at Charité - Universitätsmedizin Berlin, BIH Center for Regenerative Therapies (BCRT), Berlin, Germany 13. Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin Center for Advanced Therapies (BeCAT), Berlin, Germany
Background: Despite the increasing global burden of osteoarthritis (OA), no disease modifying drug has yet advanced to market entry. Market approval is often not reached, because preclinical data for novel OA therapeutics can not be reproduced clinically. Among others, this may be due to the choice of the OA model (primary vs. secondary) and the degree of OA addressed (mild to moderate vs. severe) which do often not match in preclinical and clinical studies.
Aim: With this study, we test the safety and efficacy of placenta-derived mesenchymal like stromal cells (PLX-PAD) for the treatment of mild- moderate primary OA in the Dunkin Hartley guinea pig model, as a basis for the PROTO consortium clinical trial.
Materials and Methods: Thirty sex-matched six-month-old Dunkin Hartley guinea pigs were randomized to receive either a single intra-articular injection of (i) PLX- PAD (1 million), (ii) PLX-PAD (2 million), or (iii) phosphate buffered saline (PBS) into the intraarticular space of both knees. All animals underwent in vivo magnetic resonance imaging (MRI) one and six months post-injection. All animals were sacrificed six months post injection, and samples were harvested for histological (OARSI grading), radiological (µ- CT), and molecular (gene and protein) analysis. Here, we present the histological and clinical data available to date.
Results: No swelling, redness or limping were observed for any of the animals regardless of treatment group throughout the study. At six months post injection, PBS treated animals presented signs of severe OA histologically, while PLX-PAD treated animals only showed a mild progression of the disease (PLX-PAD, 1 million, p=0.007; PLX-PAD, 2 million, p=0.066). No animals showed ectopic bone formation or severe synovial infiltration.
Interpretation / Conclusion: These initial histological and clinical results indicate PLX-PAD is biologically active with no local toxicity observed in this model of mild- moderate primary OA compared to placebo. Further evaluation of radiological and molecular data will enable the PROTO consortium (funded by Horizon Europe Grant Nr. 101095635) to translate these preclinical findings into a human phase I/IIa trial, which matches the disease type and severity of the preclinical model.
Julie B. Pajaniaye1,2,3, Peter Alsing1,2, Martin B. Stisen2,4, Erzsébet Horváth-Puhó1,4, Maaike Gademan5,6, Alma B. Pedersen1,4, Inger Mechlenburg2,4
1. Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark 2. Department of Orthopaedic Surgery, Aarhus University Hospital, Aarhus, Denmark 3. Department of Dentistry and Oral Health, Aarhus University,Aarhus, Denmark 4. Department of Clinical Medicine, Aarhus University, Aarhus, Denmark 5. Department of Orthopaedics, Leiden University Medical Centre, University of Leiden, Leiden, the Netherlands; 6. Department of Clinical Epidemiology, Leiden University Medical Centre, University of Leiden, Leiden, the Netherlands
Background: Total knee arthroplasty (TKA) is an effective and safe treatment of pain and functional impairment in late-stage knee osteoarthritis (OA). In Denmark, 20% of TKAs are performed in patients <60 years of age who can return to work (RTW) after TKA. However, there is limited knowledge about the rate of RTW in this population. Obesity, a major risk factor for TKA complications in terms of incidence and severity, may affect RTW after TKA.
Aim: To investigate the association between body mass index (BMI) and rates of RTW in working-age patients with knee OA undergoing TKA. Furthermore, to explore whether the association varies by sex, age, socioeconomic position (SEP), and history of comorbidities.
Materials and Methods: We combined data from the Danish Knee Arthroplasty Registry and the Danish Registry for Evaluation of Marginalization, for labor market status. BMI was grouped as normal (<25), pre-obesity (25-29.9), obesity class 1 (30-34.9), 2 (35-39.9), or 3 (=40). RTW was defined as full- or part-time RTW within 2 years of follow-up. We estimated cumulative incidence proportions (CIP) of RTW (overall and by BMI-group), considering death and early retirement as competing events. Cox proportional hazards models were used to calculate Hazard Ratios (HRs) adjusting for selected confounders.
Results: We included 6,162 patients (41% men), median age 55 years (IQR 6.3) and mean BMI 30.8 (95% CI (CI) 30.7;31). The median time to RTW was 69 days (CI 67.6;70). The CIP of RTW at 1 month was 31% (CI: 30;32), at 3 months was 63% (CI 62;65), at 1 year was 92% (CI 92;93), and at 2 years was 96% (CI 95;96). CIPs for RTW in BMI-groups were similar to the overall CIPs, and HRs in BMI-groups were equal to 1. Stratification by age, SEP and comorbidity did not change HRs. Stratification by sex showed no association between BMI and RTW for women, while men in higher BMI-groups had a tendency to lower rate of RTW (HR for obesity class 2 was 0.9 (CI 0.7;1), HR for obesity class 3 was 0.8 (CI 0.7;1) compared to normal BMI).
Interpretation / Conclusion: 31% of TKA patients RTW within 30 days and over 90% RTW within one year. Obesity was not found to affect RTW, but men in obesity class 2 and 3 may need tailored post-TKA rehabilitation to facilitate RTW.
1. Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark 2. Department of Orthopaedic Surgery, Aarhus University Hospital, Aarhus, Denmark 3. Department of Dentistry and Oral Health, Aarhus University,Aarhus, Denmark 4. Department of Clinical Medicine, Aarhus University, Aarhus, Denmark 5. Department of Orthopaedics, Leiden University Medical Centre, University of Leiden, Leiden, the Netherlands; 6. Department of Clinical Epidemiology, Leiden University Medical Centre, University of Leiden, Leiden, the Netherlands
Background: Total knee arthroplasty (TKA) is an effective and safe treatment of pain and functional impairment in late-stage knee osteoarthritis (OA). In Denmark, 20% of TKAs are performed in patients <60 years of age who can return to work (RTW) after TKA. However, there is limited knowledge about the rate of RTW in this population. Obesity, a major risk factor for TKA complications in terms of incidence and severity, may affect RTW after TKA.
Aim: To investigate the association between body mass index (BMI) and rates of RTW in working-age patients with knee OA undergoing TKA. Furthermore, to explore whether the association varies by sex, age, socioeconomic position (SEP), and history of comorbidities.
Materials and Methods: We combined data from the Danish Knee Arthroplasty Registry and the Danish Registry for Evaluation of Marginalization, for labor market status. BMI was grouped as normal (<25), pre-obesity (25-29.9), obesity class 1 (30-34.9), 2 (35-39.9), or 3 (=40). RTW was defined as full- or part-time RTW within 2 years of follow-up. We estimated cumulative incidence proportions (CIP) of RTW (overall and by BMI-group), considering death and early retirement as competing events. Cox proportional hazards models were used to calculate Hazard Ratios (HRs) adjusting for selected confounders.
Results: We included 6,162 patients (41% men), median age 55 years (IQR 6.3) and mean BMI 30.8 (95% CI (CI) 30.7;31). The median time to RTW was 69 days (CI 67.6;70). The CIP of RTW at 1 month was 31% (CI: 30;32), at 3 months was 63% (CI 62;65), at 1 year was 92% (CI 92;93), and at 2 years was 96% (CI 95;96). CIPs for RTW in BMI-groups were similar to the overall CIPs, and HRs in BMI-groups were equal to 1. Stratification by age, SEP and comorbidity did not change HRs. Stratification by sex showed no association between BMI and RTW for women, while men in higher BMI-groups had a tendency to lower rate of RTW (HR for obesity class 2 was 0.9 (CI 0.7;1), HR for obesity class 3 was 0.8 (CI 0.7;1) compared to normal BMI).
Interpretation / Conclusion: 31% of TKA patients RTW within 30 days and over 90% RTW within one year. Obesity was not found to affect RTW, but men in obesity class 2 and 3 may need tailored post-TKA rehabilitation to facilitate RTW.
Oddrún Danielsen1,2, Christian Bredgaard Jensen1,3, Claus Varnum1,4, Thomas Jakobsen1,5, Mikkel Rathsach Andersen1,6, Manuel Josef Bieder1,7, Søren Overgaard1,8,9, Christoffer Calov Jørgensen1,10, Kirill Gromov1,3, Henrik Kehlet1,11, Martin Lindberg-Larsen1,2
1. Center for Fast-track Hip and Knee Replacement, Denmark 2. Dept. of Orthopaedic Surgery and traumatology, Odense University Hospital and Svendborg 3. Dept. of Orthopaedic Surgery, Hvidovre University Hospital 4. Dept. of Orthopaedic Surgery, Lillebaelt Hospital – Vejle 5. Dept. of Orthopaedic Surgery, Aalborg University Hospital 6. Dept. of Orthopaedic Surgery, Copenhagen University Hospital, Herlev-Gentofte 7. Dept. of Orthopaedic surgery, Næstved, Slagelse and Ringsted Hospitals 8. Dept. of Orthopaedic Surgery and Traumatology, Copenhagen University Hospital, Bispebjerg 9. University of Copenhagen, Department of Clinical Medicine, Faculty of Health and Medical Sciences 10. Dept. of Anaesthesia, Hospital of Northern Zeeland, Hillerød 11. Section of Surgical Pathophysiology, Copenhagen University Hospital, Rigshospitalet
Background: Day-case success rates after primary total hip arthroplasty (THA), total knee arthroplasty (TKA) and medial unicompartmental knee arthroplasty (mUKA) may vary and detailed data is needed on causes of not being discharged.
Aim: The aim of this study was to analyse the association of surgical procedure type on successful day-case surgery. Furthermore, to analyse causes of not being discharged on day of surgery when eligible and scheduled for day-case THA, TKA and mUKA.
Materials and Methods: A multicentre prospective consecutive cohort study from September 2022 to August 2023. Patients were screened for day-case eligibility using well- defined in- and exclusion criteria and discharged when fulfilling predetermined discharge criteria. Day-case eligible patients were scheduled for surgery with intended start of surgery before 1 p.m.
Results: Of 6,142 primary hip and knee arthroplasties, eligibility rates for day-case were 34% for THA (95% confidence interval 32-36), 34% for TKA (32-36) and 52% for mUKA (49-55). Surgery before 1.p.m. were achieved in 85% of eligible patients with day-case success rates of 59% (55- 62) for THA, 61% (57-65) for TKA, and 72% (68- 76) for mUKA. Overall day-case success rates (eligible and non-eligible) were 19% (17-20) for THA, 20% (18-21) for TKA and 42% (39-45) for mUKA. Adjusted analysis confirmed higher day- case success in eligible mUKA patients (Odds Ratio 1.9 (1.6-2.3)) compared to TKA and THA patients. Primary causes for day-case failure were mobilization issues (9-12% between procedures), prolonged spinal anaesthesia (4- 9%) and postoperative nausea and vomiting (PONV) (4-14%).
Interpretation / Conclusion: THA and TKA patients showed comparable eligibility (34%) with similar day-case success rates (59- 61%), whereas mUKA patients demonstrated higher eligibility (52%) and day-case success (72%). Mobilization issues, prolonged spinal anaesthesia and PONV were the most frequent causes for not being discharged.
1. Center for Fast-track Hip and Knee Replacement, Denmark 2. Dept. of Orthopaedic Surgery and traumatology, Odense University Hospital and Svendborg 3. Dept. of Orthopaedic Surgery, Hvidovre University Hospital 4. Dept. of Orthopaedic Surgery, Lillebaelt Hospital – Vejle 5. Dept. of Orthopaedic Surgery, Aalborg University Hospital 6. Dept. of Orthopaedic Surgery, Copenhagen University Hospital, Herlev-Gentofte 7. Dept. of Orthopaedic surgery, Næstved, Slagelse and Ringsted Hospitals 8. Dept. of Orthopaedic Surgery and Traumatology, Copenhagen University Hospital, Bispebjerg 9. University of Copenhagen, Department of Clinical Medicine, Faculty of Health and Medical Sciences 10. Dept. of Anaesthesia, Hospital of Northern Zeeland, Hillerød 11. Section of Surgical Pathophysiology, Copenhagen University Hospital, Rigshospitalet
Background: Day-case success rates after primary total hip arthroplasty (THA), total knee arthroplasty (TKA) and medial unicompartmental knee arthroplasty (mUKA) may vary and detailed data is needed on causes of not being discharged.
Aim: The aim of this study was to analyse the association of surgical procedure type on successful day-case surgery. Furthermore, to analyse causes of not being discharged on day of surgery when eligible and scheduled for day-case THA, TKA and mUKA.
Materials and Methods: A multicentre prospective consecutive cohort study from September 2022 to August 2023. Patients were screened for day-case eligibility using well- defined in- and exclusion criteria and discharged when fulfilling predetermined discharge criteria. Day-case eligible patients were scheduled for surgery with intended start of surgery before 1 p.m.
Results: Of 6,142 primary hip and knee arthroplasties, eligibility rates for day-case were 34% for THA (95% confidence interval 32-36), 34% for TKA (32-36) and 52% for mUKA (49-55). Surgery before 1.p.m. were achieved in 85% of eligible patients with day-case success rates of 59% (55- 62) for THA, 61% (57-65) for TKA, and 72% (68- 76) for mUKA. Overall day-case success rates (eligible and non-eligible) were 19% (17-20) for THA, 20% (18-21) for TKA and 42% (39-45) for mUKA. Adjusted analysis confirmed higher day- case success in eligible mUKA patients (Odds Ratio 1.9 (1.6-2.3)) compared to TKA and THA patients. Primary causes for day-case failure were mobilization issues (9-12% between procedures), prolonged spinal anaesthesia (4- 9%) and postoperative nausea and vomiting (PONV) (4-14%).
Interpretation / Conclusion: THA and TKA patients showed comparable eligibility (34%) with similar day-case success rates (59- 61%), whereas mUKA patients demonstrated higher eligibility (52%) and day-case success (72%). Mobilization issues, prolonged spinal anaesthesia and PONV were the most frequent causes for not being discharged.
Emil Toft Petersen1,2,3, Karina Nørgaard Linde1,2,3, Carl Christian Holkgaard Burvil1,3, Søren Rytter1,2,3, Daan Koppens1,2,3, Jesper Dalsgaard4, Torben Bæk Hansen3,4, Maiken Stilling1,2,3
1. AutoRSA Research Group, Orthopaedic Research Unit, Aarhus University Hospital, Aarhus N, Denmark; 2. Department of Orthopedic Surgery, Aarhus University Hospital, Aarhus N, Denmark; 3. Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; 4. Department of Orthopedics, Gødstrup Regional Hospital, Gødstrup, Denmark;
Background: Osteoarthritic changes often cause knee malalignment before total knee arthroplasty, altering bone loading compared to non- osteoarthritic knees. This malalignment is corrected during surgery, balancing the ligaments. Nonetheless, preoperative gait patterns may influence postoperative prosthesis load and bone support, potentially affecting component migration.
Aim: Investigating the impact of preoperative gait patterns on postoperative femoral and tibial component migration in total knee arthroplasty.
Materials and Methods: In a prospective cohort study, 66 patients with primary knee osteoarthritis undergoing cemented Persona total knee arthroplasty were assessed. Preoperative knee kinematics was analyzed through dynamic radiostereometry and motion capture, categorizing patients into four homogeneous gait patterns. The four subgroups were labeled as the flexion group (n = 20), the abduction (valgus) group (n = 17), the anterior drawer group (n = 10), and the tibial external rotation group (n = 19). The femoral and tibial component migration was measured using static radiostereometry taken supine on the postoperative day (baseline) and 3-, 12-, and 24-months post-surgery. Migration was evaluated as maximum total point motion (MTPM).
Results: Of the preoperatively defined four subgroups, the abduction group with a valgus-characterized gait pattern exhibited the highest migration for both the femoral (1.64 mm (CI95% 1.25; 2.03)) and tibial (1.21 mm (CI95% 0.89; 1.53)) components at 24-month follow- up. For the femoral components, the abduction group migrated 0.6 mm (CI95% 0.08; 1.12) more than the external rotation group at 24 months. For the tibial components, the abduction group migrated 0.43 mm (CI95% 0.16; 0.70) more than the external rotation group at 3 months. Furthermore, at 12- and 24-months follow-up the abduction group migrated 0.39 mm (95% CI 0.04; 0.73) and 0.45 mm (0.01; 0.89) more than the flexion group, respectively.
Interpretation / Conclusion: A preoperative valgus-characterized gait pattern seems to increase femoral and tibial component migration until 2 years of follow- up. This suggests that the implant fixation depends on load distributions originating from specific preoperative gait patterns.
1. AutoRSA Research Group, Orthopaedic Research Unit, Aarhus University Hospital, Aarhus N, Denmark; 2. Department of Orthopedic Surgery, Aarhus University Hospital, Aarhus N, Denmark; 3. Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; 4. Department of Orthopedics, Gødstrup Regional Hospital, Gødstrup, Denmark;
Background: Osteoarthritic changes often cause knee malalignment before total knee arthroplasty, altering bone loading compared to non- osteoarthritic knees. This malalignment is corrected during surgery, balancing the ligaments. Nonetheless, preoperative gait patterns may influence postoperative prosthesis load and bone support, potentially affecting component migration.
Aim: Investigating the impact of preoperative gait patterns on postoperative femoral and tibial component migration in total knee arthroplasty.
Materials and Methods: In a prospective cohort study, 66 patients with primary knee osteoarthritis undergoing cemented Persona total knee arthroplasty were assessed. Preoperative knee kinematics was analyzed through dynamic radiostereometry and motion capture, categorizing patients into four homogeneous gait patterns. The four subgroups were labeled as the flexion group (n = 20), the abduction (valgus) group (n = 17), the anterior drawer group (n = 10), and the tibial external rotation group (n = 19). The femoral and tibial component migration was measured using static radiostereometry taken supine on the postoperative day (baseline) and 3-, 12-, and 24-months post-surgery. Migration was evaluated as maximum total point motion (MTPM).
Results: Of the preoperatively defined four subgroups, the abduction group with a valgus-characterized gait pattern exhibited the highest migration for both the femoral (1.64 mm (CI95% 1.25; 2.03)) and tibial (1.21 mm (CI95% 0.89; 1.53)) components at 24-month follow- up. For the femoral components, the abduction group migrated 0.6 mm (CI95% 0.08; 1.12) more than the external rotation group at 24 months. For the tibial components, the abduction group migrated 0.43 mm (CI95% 0.16; 0.70) more than the external rotation group at 3 months. Furthermore, at 12- and 24-months follow-up the abduction group migrated 0.39 mm (95% CI 0.04; 0.73) and 0.45 mm (0.01; 0.89) more than the flexion group, respectively.
Interpretation / Conclusion: A preoperative valgus-characterized gait pattern seems to increase femoral and tibial component migration until 2 years of follow- up. This suggests that the implant fixation depends on load distributions originating from specific preoperative gait patterns.