Session 9: Hip I
Torsdag d. 26. oktober
13:00-14:30
Lokale: Reykjavik
Chairmen: Stig Jakobsen og Thomas Jakobsen
Peter Bo Jørgensen, Martin Lamm, Kjeld Søballe, Maiken Stilling
Department of Orthopedic Surgery, Department of Clinical Medicine, Aarhus University Hospital, Aarhus University; Department of Orthopedic Surgery, Department of Clinical Medicine, Aarhus University Hospital, Aarhus University; Department of Orthopedic Surgery, Department of Clinical Medicine, Aarhus University Hospital, Aarhus University; Department of Orthopedic Surgery, Department of Clinical Medicine, Aarhus University Hospital, Aarhus University
Background: Long-term fixation of cemented femoral stems relies on several factors including cement-adhesion and -fatigue. Hi-Fatigue Bone Cement (HF) is a third-generation high viscosity bone cement that initially, during and after mixing, has a lower viscosity compared to Palacos® Bone Cement (P). This allows for low porosity, good mechanical strength, and a stable bone-cement interface with optimal bone penetration. P shows excellent 10-year survival with CPT-stem (98.7%) and is considered gold standard. Subsidence of cemented femoral stems at 2-year follow-up has been shown to predictive of revision.
Purpose / Aim of Study: The purpose of the study was to compare stem subsidence after fixation with HF and P bone cements.
Materials and Methods: The study design was a patient- blinded, randomized, controlled study. Based on a sample size calculation, fifty-two patients with osteoarthrosis (age>70, t-score>-2.5) were block- randomized to HF (Zimmer) or P (Haereus). Patients received CPT stems (12-14 conus Cr-Co) (Zimmer) and 6-8 tantalum beads. Bone- cements were vacuum-mixed and the time for cement phases systematically registered. Supine stereoradiographs were obtained, and clinical outcomes were OHS and VAS pain. Follow-up was performed at postop, 3 and 6 months, 1 and 2 years.
Findings / Results: Mean subsidence was similar (p=0.68) for HF (1.12 mm (SD 0.42)) and P (1.19 mm (SD 0.38)). There were no differences in total translation (p=0.67) and total rotation (p=0.15). Mean OHS was 41.5 (SD 8.6) and mean VAS pain was 1.1 (SD 2.2) (p>0.78). Cement working times were similar, but the curing time was longer for H (13:43 min) than for P (11:35 min) (p= 0.00).
Conclusions: Fixation of the CPT femoral stem was equivalent with Hi-Fatigue and Palacos bone cements up to 2 years follow-up. Based on the predictive value of RSA we also expect equivalent long-term results.
Department of Orthopedic Surgery, Department of Clinical Medicine, Aarhus University Hospital, Aarhus University; Department of Orthopedic Surgery, Department of Clinical Medicine, Aarhus University Hospital, Aarhus University; Department of Orthopedic Surgery, Department of Clinical Medicine, Aarhus University Hospital, Aarhus University; Department of Orthopedic Surgery, Department of Clinical Medicine, Aarhus University Hospital, Aarhus University
Background: Long-term fixation of cemented femoral stems relies on several factors including cement-adhesion and -fatigue. Hi-Fatigue Bone Cement (HF) is a third-generation high viscosity bone cement that initially, during and after mixing, has a lower viscosity compared to Palacos® Bone Cement (P). This allows for low porosity, good mechanical strength, and a stable bone-cement interface with optimal bone penetration. P shows excellent 10-year survival with CPT-stem (98.7%) and is considered gold standard. Subsidence of cemented femoral stems at 2-year follow-up has been shown to predictive of revision.
Purpose / Aim of Study: The purpose of the study was to compare stem subsidence after fixation with HF and P bone cements.
Materials and Methods: The study design was a patient- blinded, randomized, controlled study. Based on a sample size calculation, fifty-two patients with osteoarthrosis (age>70, t-score>-2.5) were block- randomized to HF (Zimmer) or P (Haereus). Patients received CPT stems (12-14 conus Cr-Co) (Zimmer) and 6-8 tantalum beads. Bone- cements were vacuum-mixed and the time for cement phases systematically registered. Supine stereoradiographs were obtained, and clinical outcomes were OHS and VAS pain. Follow-up was performed at postop, 3 and 6 months, 1 and 2 years.
Findings / Results: Mean subsidence was similar (p=0.68) for HF (1.12 mm (SD 0.42)) and P (1.19 mm (SD 0.38)). There were no differences in total translation (p=0.67) and total rotation (p=0.15). Mean OHS was 41.5 (SD 8.6) and mean VAS pain was 1.1 (SD 2.2) (p>0.78). Cement working times were similar, but the curing time was longer for H (13:43 min) than for P (11:35 min) (p= 0.00).
Conclusions: Fixation of the CPT femoral stem was equivalent with Hi-Fatigue and Palacos bone cements up to 2 years follow-up. Based on the predictive value of RSA we also expect equivalent long-term results.
Viktoria Lindberg-Larsen, Pelle Petersen, Øivind Jans, Torben Beck, Henrik Kehlet
Section for Surgical Pathophysiology, Rigshospitalet; Section for Surgical Pathophysiology, Rigshospitalet; The Lundbeck Foundation Centre for Fast-Track Hip and Knee Arthroplasty, The Lundbeck Foundation Centre for Fast-Track Hip and Knee Arthroplasty; Department of Orthopaedic Surgery, Bispebjerg and Frederiksberg Hospital; Section for Surgical Pathophysiology, Rigshospitalet
Background: Orthostatic hypotension (OH) and intolerance (OI) are common after total hip arthroplasty (THA) and may delay early mobilization as well as increase the risk of fainting and falling. The pathology of OH and OI includes a dysregulated postoperative vasopressor response, by a hitherto unknown mechanism.
Purpose / Aim of Study: We hypothesized that OH and OI could potentially be related to the inflammatory stress response which is inhibited by steroid administration. Consequently, this study evaluated the effect of a preoperative high- dose methylprednisolone on OH and OI early after THA.
Materials and Methods: A randomized, double-blind, placebo-controlled study in 59 patients undergoing elective unilateral THA with spinal anesthesia and a standardized multimodal analgesic regime. Patients were allocated (1:1) to preoperative intravenous (IV) methylprednisolone (MP) 125 mg or isotonic saline (C). OH, OI and cardiovascular responses were evaluated using a standardized mobilization protocol preoperatively, 6, and 24 hours after surgery. Systolic (SAP) and diastolic (DAP) arterial pressure and heart rate (HR) were measured non-invasively (Nexfin®). The systemic inflammation was monitored by C- reactive protein (CRP).
Findings / Results: At 6 hours postoperatively, 11 (38%) versus 11 (37%) patients had OH in group MP and group C, respectively (RR 0.97 (0.58 to 1.64; p=0.92)), whereas OI was present in 9 (31%) versus 13 (43%) patients (RR 1.29 (0.79 to 2.11; p=0.33)), respectively. At 24 hours postoperatively, the prevalence of OH and OI did not differ between groups (p=0.24 and p=0.11, respectively), though CRP levels were significantly reduced in group MP (p<0.001).
Conclusions: Preoperative administration of 125 mg methylprednisolone did not reduce the prevalence of OH or OI compared with placebo despite a reduced systemic inflammatory response.
Section for Surgical Pathophysiology, Rigshospitalet; Section for Surgical Pathophysiology, Rigshospitalet; The Lundbeck Foundation Centre for Fast-Track Hip and Knee Arthroplasty, The Lundbeck Foundation Centre for Fast-Track Hip and Knee Arthroplasty; Department of Orthopaedic Surgery, Bispebjerg and Frederiksberg Hospital; Section for Surgical Pathophysiology, Rigshospitalet
Background: Orthostatic hypotension (OH) and intolerance (OI) are common after total hip arthroplasty (THA) and may delay early mobilization as well as increase the risk of fainting and falling. The pathology of OH and OI includes a dysregulated postoperative vasopressor response, by a hitherto unknown mechanism.
Purpose / Aim of Study: We hypothesized that OH and OI could potentially be related to the inflammatory stress response which is inhibited by steroid administration. Consequently, this study evaluated the effect of a preoperative high- dose methylprednisolone on OH and OI early after THA.
Materials and Methods: A randomized, double-blind, placebo-controlled study in 59 patients undergoing elective unilateral THA with spinal anesthesia and a standardized multimodal analgesic regime. Patients were allocated (1:1) to preoperative intravenous (IV) methylprednisolone (MP) 125 mg or isotonic saline (C). OH, OI and cardiovascular responses were evaluated using a standardized mobilization protocol preoperatively, 6, and 24 hours after surgery. Systolic (SAP) and diastolic (DAP) arterial pressure and heart rate (HR) were measured non-invasively (Nexfin®). The systemic inflammation was monitored by C- reactive protein (CRP).
Findings / Results: At 6 hours postoperatively, 11 (38%) versus 11 (37%) patients had OH in group MP and group C, respectively (RR 0.97 (0.58 to 1.64; p=0.92)), whereas OI was present in 9 (31%) versus 13 (43%) patients (RR 1.29 (0.79 to 2.11; p=0.33)), respectively. At 24 hours postoperatively, the prevalence of OH and OI did not differ between groups (p=0.24 and p=0.11, respectively), though CRP levels were significantly reduced in group MP (p<0.001).
Conclusions: Preoperative administration of 125 mg methylprednisolone did not reduce the prevalence of OH or OI compared with placebo despite a reduced systemic inflammatory response.
René Cordtz, Samuel Hawley, Daniel Prieto-Alhambra, Kristian Zobbe, Pil Højgaard, Lars Erik Kristensen, Søren Overgaard, Anders Odgaard, Lene Dreyer
Department of Rheumatology, Gentofte Hospital, Center for Rheumatology and Spine Diseases, Rigshospitalet; Musculoskeletal Pharmaco- and Device Epidemiology, NDORMS, University of Oxford; Musculoskeletal Pharmaco- and Device Epidemiology, NDORMS, University of Oxford; Department of Rheumatology, Gentofte Hospital, Center for Rheumatology and Spine Diseases, Rigshospitalet; The Parker Institute, Bispebjerg and Frederiksberg Hospital; The Parker Institute, Bispebjerg and Frederiksberg Hospital; Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Orthopaedic Surgery, Copenhagen University Hospital Herlev-Gentofte; Department of Rheumatology, Gentofte Hospital, Center for Rheumatology and Spine Diseases, Rigshospitalet
Background: Previous data have been conflicting regarding an impact of biological Disease Modifying Anti-Rheumatic Drugs (bDMARDs) on the incidence rate (IR) of total hip/total knee replacement (THR/TKR) in rheumatoid arthritis (RA) patients.
Purpose / Aim of Study: To investigate the impact of bDMARD introduction for the treatment of RA on the IR of THR and TKR compared with general population comparators (GPC).
Materials and Methods: Interrupted time-series analysis using the National Patient Register. Each incident RA patient diagnosed at a rheumatology department from 1996-2011 was matched with 10 GPC. We calculated 5-year age- and sex-standardised IR of THR and TKR for RA patients and GPC diagnosed/matched in each 6-month period from 1996-2011. Trends in the pre-bDMARD era (1996-2001) were compared with trends in the bDMARD era (2003-16) using segmented linear regression and a 1-year lag period (2002-03) at the time of bDMARD implementation.
Findings / Results: We identified 30 868 incident RA patients (mean age 58 years, 70% women) and 301 527 GPC. THR: For GPC, the IR increased throughout the entire study period (1996 IR: 2.9/1000 PY; year 1996-2001: +0.11/1000 PY; year 2003-16: +0.02/1000 PY). For RA patients, the IR decreased from 1996 to 2016 (1996 IR: 8.7/1000 PY; year -0.36/1000 PY). TKR: The IR increased among RA patients from 1996-2001 (1996 IR: 5.9/1000 PY; year +0.19/1000 PY), but immediately started decreasing from 2003 (year -0.20/1000 PY). The IR increased in GPC throughout the entire study period (1996 IR: 0.4/1000 PY; year 1996-2001: +0.21/1000 PY; year 2003-16: +0.08/1000 PY).
Conclusions: In 1996, the IR of THR and TKR was 3 and 15-fold higher among RA patients compared with GPC. In RA patients, bDMARD introduction was associated with decreasing IR of TKR, but not THR. IR of THR and TKR increased for GPC throughout the entire study period.
Department of Rheumatology, Gentofte Hospital, Center for Rheumatology and Spine Diseases, Rigshospitalet; Musculoskeletal Pharmaco- and Device Epidemiology, NDORMS, University of Oxford; Musculoskeletal Pharmaco- and Device Epidemiology, NDORMS, University of Oxford; Department of Rheumatology, Gentofte Hospital, Center for Rheumatology and Spine Diseases, Rigshospitalet; The Parker Institute, Bispebjerg and Frederiksberg Hospital; The Parker Institute, Bispebjerg and Frederiksberg Hospital; Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Orthopaedic Surgery, Copenhagen University Hospital Herlev-Gentofte; Department of Rheumatology, Gentofte Hospital, Center for Rheumatology and Spine Diseases, Rigshospitalet
Background: Previous data have been conflicting regarding an impact of biological Disease Modifying Anti-Rheumatic Drugs (bDMARDs) on the incidence rate (IR) of total hip/total knee replacement (THR/TKR) in rheumatoid arthritis (RA) patients.
Purpose / Aim of Study: To investigate the impact of bDMARD introduction for the treatment of RA on the IR of THR and TKR compared with general population comparators (GPC).
Materials and Methods: Interrupted time-series analysis using the National Patient Register. Each incident RA patient diagnosed at a rheumatology department from 1996-2011 was matched with 10 GPC. We calculated 5-year age- and sex-standardised IR of THR and TKR for RA patients and GPC diagnosed/matched in each 6-month period from 1996-2011. Trends in the pre-bDMARD era (1996-2001) were compared with trends in the bDMARD era (2003-16) using segmented linear regression and a 1-year lag period (2002-03) at the time of bDMARD implementation.
Findings / Results: We identified 30 868 incident RA patients (mean age 58 years, 70% women) and 301 527 GPC. THR: For GPC, the IR increased throughout the entire study period (1996 IR: 2.9/1000 PY; year 1996-2001: +0.11/1000 PY; year 2003-16: +0.02/1000 PY). For RA patients, the IR decreased from 1996 to 2016 (1996 IR: 8.7/1000 PY; year -0.36/1000 PY). TKR: The IR increased among RA patients from 1996-2001 (1996 IR: 5.9/1000 PY; year +0.19/1000 PY), but immediately started decreasing from 2003 (year -0.20/1000 PY). The IR increased in GPC throughout the entire study period (1996 IR: 0.4/1000 PY; year 1996-2001: +0.21/1000 PY; year 2003-16: +0.08/1000 PY).
Conclusions: In 1996, the IR of THR and TKR was 3 and 15-fold higher among RA patients compared with GPC. In RA patients, bDMARD introduction was associated with decreasing IR of TKR, but not THR. IR of THR and TKR increased for GPC throughout the entire study period.
Maja Tang Jensen, Per Kjærsgaard-Andersen, Søren Overgaard, Claus Varnum
Department of Orthopaedic Surgery, Department of Clinical Research, , Vejle Hospital, University of Southern Denmark,; Department of Orthopaedic Surgery, Vejle Hospital; Department of Clinical Research, Department of Orthopaedic Surgery and Traumatology, University of Southern Denmark, Odense University Hospital.; Department of Orthopaedic Surgery, Vejle Hospital
Background: The Mitch proximal epiphyseal replacement (PER) was developed to preserve proximal femoral bone and minimize femoral neck fracture associated with hip resurfacing arthroplasty (HRA). There are no mid-term results on HRA from Denmark and to our knowledge, there are no studies on the Mitch PER.
Purpose / Aim of Study: 1) To study survival and risk of revision for HRAs compared to cementless metal-on-polyethylene total hip arthroplasty (MoP THA). 2) To study the survival and risk of revision for the Mitch proximal epiphyseal replacement (PER) compared to MoP THA.
Materials and Methods: Using propensity score, we matched 1) 1.057 HRA to 1.057 cementless MoP THA and 2) 202 Mitch PER to 1010 cementless MoP THA from the Danish Hip Arthroplasty Register. To estimate the relative risk (RR) of revision, we used regression with the pseudo-value approach and treated death as a competing risk. 95% confidence intervals were estimated.
Findings / Results: 1) Median follow-up was 7.7 (interquartile range (IQR): 6.4-8.4) years for HRA and 7.5 (IQR: 6.2-9.1) for MoP THA. The cumulative incidence for any revision of HRA at 10 years follow-up was 11.0% (CI: 8.5-12.3) and 6.3% (CI: 5.6-6.4) for MoP THA. The RR of revision was 1.57 (CI: 1.16-2.12) for HRAs at 10 years follow-up. By excluding the ASR components, the RR of revision at 10 years was 1.26 (CI: 0.90-1.78). 2) Median follow-up was 6.6 (IQR: 5.8-7.5) years for Mitch PER and 6.6 (IQR: 5.7-7.3) years for MoP THA. The cumulative incidence of revision was 9.6% (CI: 4.2-17.7) for Mitch PER and 5.4% (CI: 5.1-5.7) for THA MoP at 8 years. The RR of revision was 2.08 (CI: 0.97-4.48) for Mitch PER at 8-years of follow-up.
Conclusions: Both HRA and Mitch PER had increased risk of revision compared to the cementless MoP THA. When excluding ASR, the HRA group had similar risk of revision compared to MoP THA.
Department of Orthopaedic Surgery, Department of Clinical Research, , Vejle Hospital, University of Southern Denmark,; Department of Orthopaedic Surgery, Vejle Hospital; Department of Clinical Research, Department of Orthopaedic Surgery and Traumatology, University of Southern Denmark, Odense University Hospital.; Department of Orthopaedic Surgery, Vejle Hospital
Background: The Mitch proximal epiphyseal replacement (PER) was developed to preserve proximal femoral bone and minimize femoral neck fracture associated with hip resurfacing arthroplasty (HRA). There are no mid-term results on HRA from Denmark and to our knowledge, there are no studies on the Mitch PER.
Purpose / Aim of Study: 1) To study survival and risk of revision for HRAs compared to cementless metal-on-polyethylene total hip arthroplasty (MoP THA). 2) To study the survival and risk of revision for the Mitch proximal epiphyseal replacement (PER) compared to MoP THA.
Materials and Methods: Using propensity score, we matched 1) 1.057 HRA to 1.057 cementless MoP THA and 2) 202 Mitch PER to 1010 cementless MoP THA from the Danish Hip Arthroplasty Register. To estimate the relative risk (RR) of revision, we used regression with the pseudo-value approach and treated death as a competing risk. 95% confidence intervals were estimated.
Findings / Results: 1) Median follow-up was 7.7 (interquartile range (IQR): 6.4-8.4) years for HRA and 7.5 (IQR: 6.2-9.1) for MoP THA. The cumulative incidence for any revision of HRA at 10 years follow-up was 11.0% (CI: 8.5-12.3) and 6.3% (CI: 5.6-6.4) for MoP THA. The RR of revision was 1.57 (CI: 1.16-2.12) for HRAs at 10 years follow-up. By excluding the ASR components, the RR of revision at 10 years was 1.26 (CI: 0.90-1.78). 2) Median follow-up was 6.6 (IQR: 5.8-7.5) years for Mitch PER and 6.6 (IQR: 5.7-7.3) years for MoP THA. The cumulative incidence of revision was 9.6% (CI: 4.2-17.7) for Mitch PER and 5.4% (CI: 5.1-5.7) for THA MoP at 8 years. The RR of revision was 2.08 (CI: 0.97-4.48) for Mitch PER at 8-years of follow-up.
Conclusions: Both HRA and Mitch PER had increased risk of revision compared to the cementless MoP THA. When excluding ASR, the HRA group had similar risk of revision compared to MoP THA.
Inger Mechlenburg, Maiken Stilling, Lone Rømer, Marleen de Bruijne, Kjeld Søballe, Sepp de Raedt
Orthopaedic Department, Aarhus University Hospital; Orthopaedic Department, Aarhus University Hospital; Radiology Department, Aarhus University Hospital; , Erasmus MC Rotterdam; Orthopaedic Department, Aarhus University Hospital; Department of Clinical Medicine, Aarhus University
Background: Acetabular angles are commonly measured when assessing a person for hip dysplasia but we have little knowledge of normal values of these angles.
Purpose / Aim of Study: The purpose of this study was to report normal values and variation of acetabular angles and to investigate gender differences.
Materials and Methods: Retrospectively, we recruited 96 subjects, 52 females, 63±12 years who had undergone computed tomography (CT) as part of examination for lymphomas in 2013 at Aarhus University Hospital. After CT, the subjects completed the Oxford Hip Score. Eight subjects indicated hip problems and 3 had missing data and those 11 were excluded from the material. The center-edge (CE), the acetabular-index (AI), the anterior-sector (AASA), the posterior-sector (PASA) and the acetabular-anteversion angle (AcAV) for both hips were measured on CT images by an experienced radiologist. The acetabular angles are reported for right and left hip as mean ± SD degrees and compared for females and men by a two-sample t-test.
Findings / Results: The CE angle [right;left] averaged [34±6;35±5]. The AI angle averaged [3±6;1±5]. The AASA averaged [58±7;60±9]. The PASA averaged [94±7;95±7]. The AcAV averaged [18±5;18±5]. The AASA was lower (p=0.03), the PASA higher (p=0.04) and the ACAV higher (p=0.0006) for females compared to men.
Conclusions: We found considerable variation in the normal values for acetabular angles. There were gender differences in the sector angles and for the ACAV, the latter supported by previous studies having described the female acetabulum as being more forward-oriented than those of men. Awareness of normal values is important when we attempt to diagnose the pathological hip conditions.
Orthopaedic Department, Aarhus University Hospital; Orthopaedic Department, Aarhus University Hospital; Radiology Department, Aarhus University Hospital; , Erasmus MC Rotterdam; Orthopaedic Department, Aarhus University Hospital; Department of Clinical Medicine, Aarhus University
Background: Acetabular angles are commonly measured when assessing a person for hip dysplasia but we have little knowledge of normal values of these angles.
Purpose / Aim of Study: The purpose of this study was to report normal values and variation of acetabular angles and to investigate gender differences.
Materials and Methods: Retrospectively, we recruited 96 subjects, 52 females, 63±12 years who had undergone computed tomography (CT) as part of examination for lymphomas in 2013 at Aarhus University Hospital. After CT, the subjects completed the Oxford Hip Score. Eight subjects indicated hip problems and 3 had missing data and those 11 were excluded from the material. The center-edge (CE), the acetabular-index (AI), the anterior-sector (AASA), the posterior-sector (PASA) and the acetabular-anteversion angle (AcAV) for both hips were measured on CT images by an experienced radiologist. The acetabular angles are reported for right and left hip as mean ± SD degrees and compared for females and men by a two-sample t-test.
Findings / Results: The CE angle [right;left] averaged [34±6;35±5]. The AI angle averaged [3±6;1±5]. The AASA averaged [58±7;60±9]. The PASA averaged [94±7;95±7]. The AcAV averaged [18±5;18±5]. The AASA was lower (p=0.03), the PASA higher (p=0.04) and the ACAV higher (p=0.0006) for females compared to men.
Conclusions: We found considerable variation in the normal values for acetabular angles. There were gender differences in the sector angles and for the ACAV, the latter supported by previous studies having described the female acetabulum as being more forward-oriented than those of men. Awareness of normal values is important when we attempt to diagnose the pathological hip conditions.
Maria Lange Kirkegaard, Merete Nørgaard Madsen, Malene Laursen, Jens Rolighed Larsen, Merete Frydenlund Pedersen, Birgitte Skovgaard, Lone Ramer Mikkelsen
Elective Surgery Centre, Silkeborg Regional Hospital; Elective Surgery Centre, Silkeborg Regional Hospital ; Elective Surgery Centre, Silkeborg Regional Hospital ; Elective Surgery Centre , Silkeborg Regional Hospital ; Elective Surgery Centre , Silkeborg Regional Hospital ; Elective Surgery Centre , Silkeborg Regional Hospital ; Elective Surgery Centre , Silkeborg Regional Hospital
Background: Length of hospital stay (LoS) following Total Hip Arthroplasty (THA) has been markedly reduced and same-day THA was recently introduced. So far, satisfactory safety and patient reported outcomes have been reported from this innovative procedure but a larger cohort is needed to provide data that may establish safety and feasibility.
Purpose / Aim of Study: The aim of the current investigation was to evaluate feasibility and safety of same-day THA in a selected Danish population.
Materials and Methods: Consecutive patients scheduled for same-day THA between Oct 2015 - Jun 2016 were included. Inclusion criteria were primary THA, motivation for a same-day procedure, age >18 years, ASA I or II, and the presence of a support person who remain with the patient 24 hr after surgery. Data were collected retrospectively from local hospital records. Outcome measures were; complications during admission, discharge readiness (before 9 PM), length of hospital stay, causes of delayed discharge, prevalence of readmission and mortality at 90-day follow-up.
Findings / Results: From 669 elective THA patients, 116 subjects were scheduled for same-day THA. 102 of 116 (88 %) were discharged according to plan with a median LoS of 10 hr. Median LoS for patients with delayed discharge was 25 hr. The primary causes of delayed discharge in 14/116 patients (12%) were: dizziness (nausea), pain and wound seepage. No hip dislocation, fracture, or any other serious complications occurred during admission. In 7 patients (6%), perioperative blood loss was above 400 ml, but all were discharged as planned. At follow- up, two patients (1.7%) had been readmitted due to infection and dislocation, respectively. In 114 patients (98 %) there were no readmissions and no fatalities.
Conclusions: The results indicate that same-day THA is feasible and safe in a selected group of patients.
Elective Surgery Centre, Silkeborg Regional Hospital; Elective Surgery Centre, Silkeborg Regional Hospital ; Elective Surgery Centre, Silkeborg Regional Hospital ; Elective Surgery Centre , Silkeborg Regional Hospital ; Elective Surgery Centre , Silkeborg Regional Hospital ; Elective Surgery Centre , Silkeborg Regional Hospital ; Elective Surgery Centre , Silkeborg Regional Hospital
Background: Length of hospital stay (LoS) following Total Hip Arthroplasty (THA) has been markedly reduced and same-day THA was recently introduced. So far, satisfactory safety and patient reported outcomes have been reported from this innovative procedure but a larger cohort is needed to provide data that may establish safety and feasibility.
Purpose / Aim of Study: The aim of the current investigation was to evaluate feasibility and safety of same-day THA in a selected Danish population.
Materials and Methods: Consecutive patients scheduled for same-day THA between Oct 2015 - Jun 2016 were included. Inclusion criteria were primary THA, motivation for a same-day procedure, age >18 years, ASA I or II, and the presence of a support person who remain with the patient 24 hr after surgery. Data were collected retrospectively from local hospital records. Outcome measures were; complications during admission, discharge readiness (before 9 PM), length of hospital stay, causes of delayed discharge, prevalence of readmission and mortality at 90-day follow-up.
Findings / Results: From 669 elective THA patients, 116 subjects were scheduled for same-day THA. 102 of 116 (88 %) were discharged according to plan with a median LoS of 10 hr. Median LoS for patients with delayed discharge was 25 hr. The primary causes of delayed discharge in 14/116 patients (12%) were: dizziness (nausea), pain and wound seepage. No hip dislocation, fracture, or any other serious complications occurred during admission. In 7 patients (6%), perioperative blood loss was above 400 ml, but all were discharged as planned. At follow- up, two patients (1.7%) had been readmitted due to infection and dislocation, respectively. In 114 patients (98 %) there were no readmissions and no fatalities.
Conclusions: The results indicate that same-day THA is feasible and safe in a selected group of patients.
Pernille Simonsen, Jens Michael Hertz, Kjeld Søballe, Inger Mechlenburg
Orthopaedic Surgery, Aarhus Universitetshospital; Human Genetic, Odense Universitetshospital; Orthopaedic Surgery, Aarhus Universitetshospital; Orthopaedic Surgery, Aarhus Universitetshospital
Background: Studies indicate that the risk of hip dysplasia is increased in cases where relatives suffer from PAO, especially first- degree relatives.
Purpose / Aim of Study: The aim of this study is thus to investigate the association between uni- or bilateral PAO, the occurrence of hip dysplasia within the family, and the degree of family relations.
Materials and Methods: This cross-sectional study consists of 815 consecutive PAO patients treated from 1998 to 2016. The information about gender, uni- or bilateral PAO and age at the time of surgery was obtained from the clinical PAO database at Aarhus University Hospital. Information about the occurrence of hip dysplasia within the family familial was collected through questionnaires. The association was assessed by using logistic regression analysis, and was divided into 615 unilateral and 200 bilateral PAO patients.
Findings / Results: Patients, who have first-degree relatives with hip dysplasia, had a 72% (OR= 1.72, 95% CI 1.17; 2.50) higher occurrence of bilateral PAO than patients without familial occurrence of hip dysplasia. This association was statistically significant (p=0.005), even when adjusting for gender and age at the time of surgery. Corresponding association was not shown among any other degree of relationship.
Conclusions: Danish patients with hip dysplasia who have first-degree relatives with hip dysplasia have increased odds of being surgically treated for bilateral PAO compared to patients without relatives with hip dysplasia. In other words having bilateral PAO indicates a greater likelihood of hip dysplasia being hereditary. Thus, this study reveals a potential new target group where genetic investigation may identify individuals with higher risk of hip dysplasia.
Orthopaedic Surgery, Aarhus Universitetshospital; Human Genetic, Odense Universitetshospital; Orthopaedic Surgery, Aarhus Universitetshospital; Orthopaedic Surgery, Aarhus Universitetshospital
Background: Studies indicate that the risk of hip dysplasia is increased in cases where relatives suffer from PAO, especially first- degree relatives.
Purpose / Aim of Study: The aim of this study is thus to investigate the association between uni- or bilateral PAO, the occurrence of hip dysplasia within the family, and the degree of family relations.
Materials and Methods: This cross-sectional study consists of 815 consecutive PAO patients treated from 1998 to 2016. The information about gender, uni- or bilateral PAO and age at the time of surgery was obtained from the clinical PAO database at Aarhus University Hospital. Information about the occurrence of hip dysplasia within the family familial was collected through questionnaires. The association was assessed by using logistic regression analysis, and was divided into 615 unilateral and 200 bilateral PAO patients.
Findings / Results: Patients, who have first-degree relatives with hip dysplasia, had a 72% (OR= 1.72, 95% CI 1.17; 2.50) higher occurrence of bilateral PAO than patients without familial occurrence of hip dysplasia. This association was statistically significant (p=0.005), even when adjusting for gender and age at the time of surgery. Corresponding association was not shown among any other degree of relationship.
Conclusions: Danish patients with hip dysplasia who have first-degree relatives with hip dysplasia have increased odds of being surgically treated for bilateral PAO compared to patients without relatives with hip dysplasia. In other words having bilateral PAO indicates a greater likelihood of hip dysplasia being hereditary. Thus, this study reveals a potential new target group where genetic investigation may identify individuals with higher risk of hip dysplasia.
Nikolaj Winther, Michael Mørk Petersen, Poul Torben Nielsen, Jens Stürup
Department of Orthopaedic Surgery, Rigshospitalet, University of Copenhagen; Department of Orthopaedic Surgery, Rigshospitalet, University of Copenhagen; Deptment of Orthopaedic Surgery, Aalborg University Hospital; Department of Orthopaedic Surgery, Rigshospitalet, University of Copenhagen
Background: Revision of a failed total hip arthroplasty (THA) with massive acetabular bone loss and pelvic discontinuity is a reconstructive challenge. Treatment options includes morselized bone graft and structural allograft used with uncemented hemispherical acetabular components, cages, porous metal augments, and cup- cage reconstruction.
Purpose / Aim of Study: The purpose of this study was to evaluate the use of a new custom-made triflanged implant for acetabular reconstruction.
Materials and Methods: We reviewed 31 patients, mean age 63.7 (48-86) years) with a failed THA and severe bone loss or pelvic discontinuity, that underwent revision THA from 2010 to 2017. Mean follow-up was 44 (10-84) months. The implant for acetabular reconstruction was custom- manufactured from Zimmer Biomet on the basis of a three-dimensional model of the hemi-pelvis created from computed tomography (CT). Preoperative radiological evaluation was made by x-ray and CT-scan and postoperative evaluation by x-ray. The Harris Hip score was performed and the acetabular bone defects were all classified as type IV/V according to the Gross classification.
Findings / Results: The mean outer diameter of the cup was 56 (52 to 62) mm. No significant intraoperative complications occurred. Mean Harris Hip score was 81 (68-97). Survivorship defined by implant failure was 100% Twenty-eight patients (90%) were free of revision. Four patients experienced dislocation (12%), two treated with a constrained liner. One re-infection (3%) revised and treated with life-long antibiotic.
Conclusions: The Custom made triflange implant for pelvic discontinuity provides a stable and rigid fixation on host bone with overall low early revision rate.
Department of Orthopaedic Surgery, Rigshospitalet, University of Copenhagen; Department of Orthopaedic Surgery, Rigshospitalet, University of Copenhagen; Deptment of Orthopaedic Surgery, Aalborg University Hospital; Department of Orthopaedic Surgery, Rigshospitalet, University of Copenhagen
Background: Revision of a failed total hip arthroplasty (THA) with massive acetabular bone loss and pelvic discontinuity is a reconstructive challenge. Treatment options includes morselized bone graft and structural allograft used with uncemented hemispherical acetabular components, cages, porous metal augments, and cup- cage reconstruction.
Purpose / Aim of Study: The purpose of this study was to evaluate the use of a new custom-made triflanged implant for acetabular reconstruction.
Materials and Methods: We reviewed 31 patients, mean age 63.7 (48-86) years) with a failed THA and severe bone loss or pelvic discontinuity, that underwent revision THA from 2010 to 2017. Mean follow-up was 44 (10-84) months. The implant for acetabular reconstruction was custom- manufactured from Zimmer Biomet on the basis of a three-dimensional model of the hemi-pelvis created from computed tomography (CT). Preoperative radiological evaluation was made by x-ray and CT-scan and postoperative evaluation by x-ray. The Harris Hip score was performed and the acetabular bone defects were all classified as type IV/V according to the Gross classification.
Findings / Results: The mean outer diameter of the cup was 56 (52 to 62) mm. No significant intraoperative complications occurred. Mean Harris Hip score was 81 (68-97). Survivorship defined by implant failure was 100% Twenty-eight patients (90%) were free of revision. Four patients experienced dislocation (12%), two treated with a constrained liner. One re-infection (3%) revised and treated with life-long antibiotic.
Conclusions: The Custom made triflange implant for pelvic discontinuity provides a stable and rigid fixation on host bone with overall low early revision rate.
Haider Ghalib Majeed, Morten Homilius, Idar Bohnhorst, Else Merete Ebbensgaard , Ahmed Salam N. Kurmasha, Torben Bæk Hansen
Department of Orthopedic, Holstebro Hospital; Department of Orthopedic, Holstebro Hospital; Department of Radiology, Holstebro Hospital; Department of Radiology, Holstebro Hospital; Department of Orthopedic, Holstebro Hospital; Department of Orthopedic, Holstebro Hospital
Background: DDH is one of the common causes of OA of the hip. Wiberg worked out a radiographic measurement, the center-edge angle(CE).
Purpose / Aim of Study: -To compare the reproducibility of CE measurements using Supine AP-Pelvis or supine AP-hip computed radiography (CR) -To investigate intra- & interobserver reproducibility between radiologists & orthopaedic surgeons.
Materials and Methods: We selected CRs of 40 patients, under the age of 60 yrs with a mean age of 40,8. The pelvis & hip CRs of all patients were anonymized & given a random order so that hip and pelvis CRs won't be recognized as paired observations 2 radiologists & 3 orthpaedic surgeons measured CE-angle of both pelvis & hip CRs without instruction/training. 2 weeks after the 1st round all CRs were given a different random order & CE-angles measured again Using Bland Altman Plots to compare the measurements of 1st & 2nd round, and to compare the measurements in pelvis vs. hip CRs. We also measured correlation coefficient for all observers & used Z-test to compare them.
Findings / Results: By using Bland Altman Plots to compare the two rounds, we found rather high limits of agreement (+/- 6-11°) with all observers in angle measurements of both pelvis & hip CRs. The same variation in angle measurements was found by using pelvis CRs or hip CRs. There was high correlation coefficient in all observers between CE angle of pelvis & CE angle of hip CRs, with range of (0,85-0,92), and no significant difference between observers (P- value 0,14-0,47)
Conclusions: There was low reproducibility of CE angle measurements regardless of using pelvis or hip CRs There was no difference in reproducibility between radiologists and orthpaedic surgeons in measurements of CE angle So, CE angle measurements must be interpreted with care, detailed instruction & training of observers in angle measurements may be required.
Department of Orthopedic, Holstebro Hospital; Department of Orthopedic, Holstebro Hospital; Department of Radiology, Holstebro Hospital; Department of Radiology, Holstebro Hospital; Department of Orthopedic, Holstebro Hospital; Department of Orthopedic, Holstebro Hospital
Background: DDH is one of the common causes of OA of the hip. Wiberg worked out a radiographic measurement, the center-edge angle(CE).
Purpose / Aim of Study: -To compare the reproducibility of CE measurements using Supine AP-Pelvis or supine AP-hip computed radiography (CR) -To investigate intra- & interobserver reproducibility between radiologists & orthopaedic surgeons.
Materials and Methods: We selected CRs of 40 patients, under the age of 60 yrs with a mean age of 40,8. The pelvis & hip CRs of all patients were anonymized & given a random order so that hip and pelvis CRs won't be recognized as paired observations 2 radiologists & 3 orthpaedic surgeons measured CE-angle of both pelvis & hip CRs without instruction/training. 2 weeks after the 1st round all CRs were given a different random order & CE-angles measured again Using Bland Altman Plots to compare the measurements of 1st & 2nd round, and to compare the measurements in pelvis vs. hip CRs. We also measured correlation coefficient for all observers & used Z-test to compare them.
Findings / Results: By using Bland Altman Plots to compare the two rounds, we found rather high limits of agreement (+/- 6-11°) with all observers in angle measurements of both pelvis & hip CRs. The same variation in angle measurements was found by using pelvis CRs or hip CRs. There was high correlation coefficient in all observers between CE angle of pelvis & CE angle of hip CRs, with range of (0,85-0,92), and no significant difference between observers (P- value 0,14-0,47)
Conclusions: There was low reproducibility of CE angle measurements regardless of using pelvis or hip CRs There was no difference in reproducibility between radiologists and orthpaedic surgeons in measurements of CE angle So, CE angle measurements must be interpreted with care, detailed instruction & training of observers in angle measurements may be required.
Rasmus Mikkelsen, Marianne Fløjstrup, Thomas Skjødt, Per Kjærsgaard-Andersen, Claus Varnum
Department of Orthopaedic Surgery, Vejle Hospital; Department of Radiology, Vejle Hospital; Department of Radiology, Vejle Hospital; Department of Orthopaedic Surgery, Vejle Hospital; Department of Orthopaedic Surgery, Vejle Hospital
Background: MRI is the most used technique for detection of adverse reaction to metal debris (ARMD), although it is costly and less available than ultrasonography (US). Few studies have measured whether US can detect ARMD.
Purpose / Aim of Study: We aimed to investigate the sensitivity and specificity of US for ARMD in patients with total hip arthroplasty (THA). We also investigated the sensitivity and specificity of US for ARMD in patients with THA with pain.
Materials and Methods: 74 patients with primary unilateral THA were included in a prospective cohort: 37 with modular neck femoral stem, 37 with nonmodular femoral stem. All patients had pain assessed and their operated hip scanned with MRI and US to look for pseudotumour (PT) and trochanteric bursitis. Results of the MRI scans were used as the gold standard when calculating sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of US.
Findings / Results: 21 patients had pain, and 53 patients had no pain. Mean age at surgery and a follow-up of 2.7 years were similar in the two groups. There were 5 PTs in the group with pain and 23 PTs in the group without pain (p=0.183). Prevalence of trochanteric bursitis was similar in the two groups (p=0.07). The sensitivity and specificity of US to detect PTs were 0.67 and 0.91, respectively, with a PPV of 0.82 and a NPV of 0.83. In patients with pain, US had a sensitivity and specificity to detect PTs of 0.60 and 0.88, respectively, and had a PPV of 0.60 and a NPV of 0.88. The sensitivity and specificity of US to detect trochanteric bursitis was 0.07 and 0.84, respectively, with a PPV of 0.09 and a NPV of 0.80.
Conclusions: US cannot replace MRI, but US did find some ARMD not seen on MRI, why it is a useful supplement to MRI for diagnosing ARMD in patients with THA. US did not perform better when used for patients with pain.
Department of Orthopaedic Surgery, Vejle Hospital; Department of Radiology, Vejle Hospital; Department of Radiology, Vejle Hospital; Department of Orthopaedic Surgery, Vejle Hospital; Department of Orthopaedic Surgery, Vejle Hospital
Background: MRI is the most used technique for detection of adverse reaction to metal debris (ARMD), although it is costly and less available than ultrasonography (US). Few studies have measured whether US can detect ARMD.
Purpose / Aim of Study: We aimed to investigate the sensitivity and specificity of US for ARMD in patients with total hip arthroplasty (THA). We also investigated the sensitivity and specificity of US for ARMD in patients with THA with pain.
Materials and Methods: 74 patients with primary unilateral THA were included in a prospective cohort: 37 with modular neck femoral stem, 37 with nonmodular femoral stem. All patients had pain assessed and their operated hip scanned with MRI and US to look for pseudotumour (PT) and trochanteric bursitis. Results of the MRI scans were used as the gold standard when calculating sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of US.
Findings / Results: 21 patients had pain, and 53 patients had no pain. Mean age at surgery and a follow-up of 2.7 years were similar in the two groups. There were 5 PTs in the group with pain and 23 PTs in the group without pain (p=0.183). Prevalence of trochanteric bursitis was similar in the two groups (p=0.07). The sensitivity and specificity of US to detect PTs were 0.67 and 0.91, respectively, with a PPV of 0.82 and a NPV of 0.83. In patients with pain, US had a sensitivity and specificity to detect PTs of 0.60 and 0.88, respectively, and had a PPV of 0.60 and a NPV of 0.88. The sensitivity and specificity of US to detect trochanteric bursitis was 0.07 and 0.84, respectively, with a PPV of 0.09 and a NPV of 0.80.
Conclusions: US cannot replace MRI, but US did find some ARMD not seen on MRI, why it is a useful supplement to MRI for diagnosing ARMD in patients with THA. US did not perform better when used for patients with pain.
Louise Mortensen, Jeppe Schultz, Anton Elsner, Stig S. Jakobsen, Kjeld Søballe, Julie S. Jakobsen, Signe Kierkegaard, Ulrik Dalgas, Inger Mechlenburg
Department of orthopaedic surgery, Aarhus University Hospital; Section of Sport Science, Department of Public Health, Aarhus University; Section of Sport Science, Department of Public Health, Aarhus University; Department of orthopaedic surgery, Aarhus University Hospital; Department of orthopaedic surgery, Aarhus University Hospital; Department of Physiotherapy, Faculty of Health Sciences, VIA University College; Department of orthopaedic surgery, Aarhus University Hospital; Section of Sport Science, Department of Public Health, Aarhus University ; Department of orthopaedic surgery, Aarhus University Hospital
Background: Exercise as treatment for optimizing surgical outcomes of periacetabular osteotomy (PAO) is sparsely investigated. Nevertheless, improving hip muscle strength through progressive resistance training (PRT) may optimize function and outcome of surgery.
Purpose / Aim of Study: To examine if PRT is feasible in patients with hip dysplasia (HD). A secondary purpose was to investigate patient reported outcomes, muscle performance and hip muscle strength following PRT.
Materials and Methods: The patients performed 8-weeks (20 sessions) of supervised PRT. Feasibility was evaluated as adherence, the number of dropouts and adverse events. Visual analog scale (VAS) was reported after each exercise and one day after training sessions. Pre- and post the intervention patients completed the Copenhagen Hip and Groin Outcome Score (HAGOS), performed two hop-tests and had their hip extensor and flexor peak torque assessed by isokinetic dynamometry.
Findings / Results: 16 patients, mean age 28 (range 22-40) years, completed the PRT intervention. No patients dropped out and no adverse events were recorded. Adherence to training was 90.3% ±9.0%. Acceptable pain levels (VAS ≤50) were reported during 95% of exercise sessions and 92.3% when assessed on the day after a training session. Four out of six HAGOS subscales improved (p <0.05), as did standing distance jump (8.3cm 95%CI [1.2, 15.3]) and countermovement jump (1.8cm 95%CI [0.7, 2.9]) on the affected side. Isokinetic concentric hip flexion peak torque showed significant improvements (15.8 Nm 95%CI [5.9, 25.8]) on the affected side, as did isometric hip flexion (11.0 NM 95%CI [1.1, 21.0]).
Conclusions: Supervised preoperative PRT is feasible in patients with HD scheduled for PAO. Furthermore, PRT may improve pain levels, patient reported outcomes, functional performance and hip flexion muscle strength.
Department of orthopaedic surgery, Aarhus University Hospital; Section of Sport Science, Department of Public Health, Aarhus University; Section of Sport Science, Department of Public Health, Aarhus University; Department of orthopaedic surgery, Aarhus University Hospital; Department of orthopaedic surgery, Aarhus University Hospital; Department of Physiotherapy, Faculty of Health Sciences, VIA University College; Department of orthopaedic surgery, Aarhus University Hospital; Section of Sport Science, Department of Public Health, Aarhus University ; Department of orthopaedic surgery, Aarhus University Hospital
Background: Exercise as treatment for optimizing surgical outcomes of periacetabular osteotomy (PAO) is sparsely investigated. Nevertheless, improving hip muscle strength through progressive resistance training (PRT) may optimize function and outcome of surgery.
Purpose / Aim of Study: To examine if PRT is feasible in patients with hip dysplasia (HD). A secondary purpose was to investigate patient reported outcomes, muscle performance and hip muscle strength following PRT.
Materials and Methods: The patients performed 8-weeks (20 sessions) of supervised PRT. Feasibility was evaluated as adherence, the number of dropouts and adverse events. Visual analog scale (VAS) was reported after each exercise and one day after training sessions. Pre- and post the intervention patients completed the Copenhagen Hip and Groin Outcome Score (HAGOS), performed two hop-tests and had their hip extensor and flexor peak torque assessed by isokinetic dynamometry.
Findings / Results: 16 patients, mean age 28 (range 22-40) years, completed the PRT intervention. No patients dropped out and no adverse events were recorded. Adherence to training was 90.3% ±9.0%. Acceptable pain levels (VAS ≤50) were reported during 95% of exercise sessions and 92.3% when assessed on the day after a training session. Four out of six HAGOS subscales improved (p <0.05), as did standing distance jump (8.3cm 95%CI [1.2, 15.3]) and countermovement jump (1.8cm 95%CI [0.7, 2.9]) on the affected side. Isokinetic concentric hip flexion peak torque showed significant improvements (15.8 Nm 95%CI [5.9, 25.8]) on the affected side, as did isometric hip flexion (11.0 NM 95%CI [1.1, 21.0]).
Conclusions: Supervised preoperative PRT is feasible in patients with HD scheduled for PAO. Furthermore, PRT may improve pain levels, patient reported outcomes, functional performance and hip flexion muscle strength.