Session 4: Poster med foredrag I
Onsdag 26. oktober
11:00 – 12:00
Lokale: Reykjavik
Chairmen: Claus Varnum / Niels Wisbeck
Søren Reinhold Jakobsen, Stig Storgaard Jakobsen, Inger Mechlenburg, Kjeld Søballe
Department of Orthopaedic Surgery, Aarhus University Hospital; Department of Orthopaedic Surgery, Aarhus University Hospital; Department of Orthopaedic Surgery, Aarhus University Hospital; Department of Orthopaedic Surgery, Aarhus University Hospital
Background: Periacetabular osteotomy (PAO) corrects underlying anatomical anomalies, reduces pain and may postpone onset of osteoarthritis in patients with symptomatic hip dysplasia. Existing evidence is based on immediate post- operative pain levels, but knowledge on pain levels corresponding to time after PAO is scarce and the association between post-operative pain levels and the degree of anatomical correction is unknown.
Purpose / Aim of Study: To examine the pain level related to different time points before and after surgery using VAS-score. Furthermore, to investigate the association between post-operative pain levels and degree of anatomical correction.
Materials and Methods: Prospective data on 426 patients operated from June 2012 to November 2015 were analysed. 285 were included. Patients were invited to answer standardized questionnaires pre-operatively, at 6 months and 2 years post-operatively. VAS-score at rest and at activity were applied as pain measurements. Paired t-tests were applied to the pre- and postoperative pain levels, and multiple regression analysis to the association between postoperative pain levels and degree of anatomical correction.
Findings / Results: We found a significant reduction of pain from pre-operative levels compared to 6 months post-operatively both at rest from 36.30 to 13.13 by 23.16 points [95% CI 20.31:26.02] (p<0.000) and during activity from 71.24 to 38.02 by 33.22 points [ 95% CI 29.50:36.93]) (p<0.000). No further reduction in pain was found from 6 months to 2 years follow-up. There was no significant association between post-operative pain levels and degree of anatomical correction (p=0.39).
Conclusions: Patients undergoing PAO can expect a significant reduction in pain both at rest and activity as early as 6 months after PAO surgery. No further pain reduction may be expected the following 2 years after surgery.
Department of Orthopaedic Surgery, Aarhus University Hospital; Department of Orthopaedic Surgery, Aarhus University Hospital; Department of Orthopaedic Surgery, Aarhus University Hospital; Department of Orthopaedic Surgery, Aarhus University Hospital
Background: Periacetabular osteotomy (PAO) corrects underlying anatomical anomalies, reduces pain and may postpone onset of osteoarthritis in patients with symptomatic hip dysplasia. Existing evidence is based on immediate post- operative pain levels, but knowledge on pain levels corresponding to time after PAO is scarce and the association between post-operative pain levels and the degree of anatomical correction is unknown.
Purpose / Aim of Study: To examine the pain level related to different time points before and after surgery using VAS-score. Furthermore, to investigate the association between post-operative pain levels and degree of anatomical correction.
Materials and Methods: Prospective data on 426 patients operated from June 2012 to November 2015 were analysed. 285 were included. Patients were invited to answer standardized questionnaires pre-operatively, at 6 months and 2 years post-operatively. VAS-score at rest and at activity were applied as pain measurements. Paired t-tests were applied to the pre- and postoperative pain levels, and multiple regression analysis to the association between postoperative pain levels and degree of anatomical correction.
Findings / Results: We found a significant reduction of pain from pre-operative levels compared to 6 months post-operatively both at rest from 36.30 to 13.13 by 23.16 points [95% CI 20.31:26.02] (p<0.000) and during activity from 71.24 to 38.02 by 33.22 points [ 95% CI 29.50:36.93]) (p<0.000). No further reduction in pain was found from 6 months to 2 years follow-up. There was no significant association between post-operative pain levels and degree of anatomical correction (p=0.39).
Conclusions: Patients undergoing PAO can expect a significant reduction in pain both at rest and activity as early as 6 months after PAO surgery. No further pain reduction may be expected the following 2 years after surgery.
Jens Bagger, Mette Hornsleth, Katja Lenz, Pia Therese Jaeger, Katrine Tanggaard, Jens Børglum, Kenneth Jensen
Department of Orthopaedic Surgery, Copenhagen University Hospital Bispebjerg; Department of Orthopaedic Surgery, Copenhagen University Hospital Bispebjerg; Departement og Anestesiology, Copenhagen University Hospital Bispebjerg; Department of Anestesiology HOC, Copenhagen University Hospital Rigshospitalet; Department of Anestiosiology, Zeeland University Hospital, Roskilde; Department of Anestiosiology, Zeeland University Hospital, Roskilde; Departement og Anestesiology, Copenhagen University Hospital Bispebjerg
Background: Pain treatment following TKA often combines systemic analgesic with peripheral nerve Blocks and local infiltration analgesia (LIA).
Purpose / Aim of Study: Wee hypothezed that a single-shot, low-volumen saphenous nerve block would improve pain and ambulation scores and reduce opioid consumption compared with placebo Blocks without LIA, and that addition of an obturator (posterior branch) nerve block would potentially confer additional benefits
Materials and Methods: 75 patients were randomized in a 1:1:1 ratio to either an ultrasound-guided saphenous nerve block (S Group), a combined saphenous/obturator nerve block (SO Group), or placebo Blocks using isotonic saline (P Group).The primary outcome was pain at 45 degree passive flexion of the knee joint in the first 24 hours after surgery. Secondary autcomes included pain at rest, morphine demand, nausea and vomiting, ambulation scores, length of stay. The nerve Blocks was add-ons to a regimen consisting of naproxem, gabapentin, zolpidem and morphine iv PCA.
Findings / Results: 74 patients were included. The S Group had less pain on movement (p<0.001) compared to placebo. This was replicated in the SO Group (p<0.05). Pain at rest and morphine demand was significantly reduced in the S Group in the first 6 hours, but the SO Group was similar to the placebo Group. Althoug nonsignificant, patients were discharged earlier in the active Groups (p=0.019 and p=0.154). There were no difference in ambulation between Groups. 28 patients had in- hospital complications, 9 of which were severe (Pneumonia, opioid intox, GI bleeding)
Conclusions: The addition of a low-volumen saphenous nerve block significantly reduced pain on movement, pain at rest and opioid demand after primary TKA, but failed to offer benefits for ambulation and length of stay. The value of adding an obtorator block remains questionable
Department of Orthopaedic Surgery, Copenhagen University Hospital Bispebjerg; Department of Orthopaedic Surgery, Copenhagen University Hospital Bispebjerg; Departement og Anestesiology, Copenhagen University Hospital Bispebjerg; Department of Anestesiology HOC, Copenhagen University Hospital Rigshospitalet; Department of Anestiosiology, Zeeland University Hospital, Roskilde; Department of Anestiosiology, Zeeland University Hospital, Roskilde; Departement og Anestesiology, Copenhagen University Hospital Bispebjerg
Background: Pain treatment following TKA often combines systemic analgesic with peripheral nerve Blocks and local infiltration analgesia (LIA).
Purpose / Aim of Study: Wee hypothezed that a single-shot, low-volumen saphenous nerve block would improve pain and ambulation scores and reduce opioid consumption compared with placebo Blocks without LIA, and that addition of an obturator (posterior branch) nerve block would potentially confer additional benefits
Materials and Methods: 75 patients were randomized in a 1:1:1 ratio to either an ultrasound-guided saphenous nerve block (S Group), a combined saphenous/obturator nerve block (SO Group), or placebo Blocks using isotonic saline (P Group).The primary outcome was pain at 45 degree passive flexion of the knee joint in the first 24 hours after surgery. Secondary autcomes included pain at rest, morphine demand, nausea and vomiting, ambulation scores, length of stay. The nerve Blocks was add-ons to a regimen consisting of naproxem, gabapentin, zolpidem and morphine iv PCA.
Findings / Results: 74 patients were included. The S Group had less pain on movement (p<0.001) compared to placebo. This was replicated in the SO Group (p<0.05). Pain at rest and morphine demand was significantly reduced in the S Group in the first 6 hours, but the SO Group was similar to the placebo Group. Althoug nonsignificant, patients were discharged earlier in the active Groups (p=0.019 and p=0.154). There were no difference in ambulation between Groups. 28 patients had in- hospital complications, 9 of which were severe (Pneumonia, opioid intox, GI bleeding)
Conclusions: The addition of a low-volumen saphenous nerve block significantly reduced pain on movement, pain at rest and opioid demand after primary TKA, but failed to offer benefits for ambulation and length of stay. The value of adding an obtorator block remains questionable
Kåre Amtoft Nissen, Torsten Grønbech Nielsen, Martin Lind
Department of Orthopedics, Aarhus University Hospital; Department of Orthopedics, Aarhus University Hospital; Department of Orthopedics, Aarhus University Hospital
Background: Allograft (AL) for anterior cruciate ligament reconstruction (ACL-R) can result in increased failure rates due to inferior biomechanical properties compared to autograft (AU) for primary ACL-R. AL is primarily used for revision ACL-R and the outcome of AL usage is poorly investigated. The Danish ACL Reconstruction Registry (DKRR) has monitored the development in ACL reconstructions since 2005.
Purpose / Aim of Study: This registry study compares clinical outcomes and re-revision rates for revision ACL-R using AL or AU.
Materials and Methods: 1619 revisions ACL-R were identified in the DKRR. These were 1315 AU procedures and 221 AL procedures. Clinical outcome after 1 year was reported using the Knee Injury and Osteoarthritis Outcome Score (KOOS), as well as Tegner function score (TFC) and objective knee stability (OKS) measurement using instrumented sagittal knee laxity side to side difference. Failure was determined as re-revision after minimum two years follow-up.
Findings / Results: At one-year follow-up the KOOS subscores for (symptoms, pain, ADL, Sport, QOL) were 67, 76, 84, 49, 46 for AL and 67, 78, 84, 51, 48 for AU with no difference between groups. OKS was 1,9±2mm for AL and 1,7±1,9mm for AU. The re-revision rate was significantly higher for AL of 12,7% compared to 5,4% for AU.
Conclusions: In this observational population-based study the re-revision rate was 2,3 times higher for AL compared to AU. However, subjective clinical outcome and knee stability were not inferior for AL patients, these results might indicate that AU is a safer graft choice for revision ACL-R.
Department of Orthopedics, Aarhus University Hospital; Department of Orthopedics, Aarhus University Hospital; Department of Orthopedics, Aarhus University Hospital
Background: Allograft (AL) for anterior cruciate ligament reconstruction (ACL-R) can result in increased failure rates due to inferior biomechanical properties compared to autograft (AU) for primary ACL-R. AL is primarily used for revision ACL-R and the outcome of AL usage is poorly investigated. The Danish ACL Reconstruction Registry (DKRR) has monitored the development in ACL reconstructions since 2005.
Purpose / Aim of Study: This registry study compares clinical outcomes and re-revision rates for revision ACL-R using AL or AU.
Materials and Methods: 1619 revisions ACL-R were identified in the DKRR. These were 1315 AU procedures and 221 AL procedures. Clinical outcome after 1 year was reported using the Knee Injury and Osteoarthritis Outcome Score (KOOS), as well as Tegner function score (TFC) and objective knee stability (OKS) measurement using instrumented sagittal knee laxity side to side difference. Failure was determined as re-revision after minimum two years follow-up.
Findings / Results: At one-year follow-up the KOOS subscores for (symptoms, pain, ADL, Sport, QOL) were 67, 76, 84, 49, 46 for AL and 67, 78, 84, 51, 48 for AU with no difference between groups. OKS was 1,9±2mm for AL and 1,7±1,9mm for AU. The re-revision rate was significantly higher for AL of 12,7% compared to 5,4% for AU.
Conclusions: In this observational population-based study the re-revision rate was 2,3 times higher for AL compared to AU. However, subjective clinical outcome and knee stability were not inferior for AL patients, these results might indicate that AU is a safer graft choice for revision ACL-R.
Martin Lindberg-Larsen, Mette Hornsleth, Jens Bagger
Department of Orthopaedic Surgery, Copenhagen University Hospital Bispebjerg; Department of Orthopaedic Surgery, Copenhagen University Hospital Bispebjerg; Department of Orthopaedic Surgery, Copenhagen University Hospital Bispebjerg
Background: Data from the Danish Knee Arthroplasty Register (DKR) has revealed high 2-year revision rates after primary knee arthroplasty performed in 2012 and 2013 in Copenhagen University Hospital Bispebjerg.
Purpose / Aim of Study: To investigate causes of early revisions in order to implement a strategy for improvement of outcome after primary knee arthroplasty.
Materials and Methods: A retrospective single center investigation of all primary knee arthroplasties performed in 2012 and 2013. During the first 15 months the Zimmer NexGen CR-Flex (n=225) was used as the standard primary knee prosthesis and in the remaining 9 months the DePuySynthes SIGMA (n=158) was used. 17 uni- compartmental prosthesis were implanted.
Findings / Results: 197 primary knee arthroplasties were performed in 2012 and 21(10.7%) were revised within 2 years, whereas 203 were performed in 2013 and 22 (10.8%) were revised within 2 years. The main cause of early revision was instability (n=20) resulting in 10 liner exchanges, 3 revisions of femoral component to posterior stabilized and 7 total revision procedures. 6 of the instability cases were fall-related and the remaining 14 were surgical procedure related. Other main causes of early revision were aseptic loosening of the tibial component (n=10) and secondary insertion of patella component (n=4).
Conclusions: Some of the early revisions (liner exchanges) due to instability could be explained by the learning curve after change of the standard prosthesis and a decrease in these revisions are expected with an increased intra- operative focus on balancing. The revisions due to aseptic loosening have led to a change in cementation technique of the tibial component. Finally, patella resurfacing is now performed as a standard procedure. With implementation of these interventions the early revision rate is expected to decrease significantly.
Department of Orthopaedic Surgery, Copenhagen University Hospital Bispebjerg; Department of Orthopaedic Surgery, Copenhagen University Hospital Bispebjerg; Department of Orthopaedic Surgery, Copenhagen University Hospital Bispebjerg
Background: Data from the Danish Knee Arthroplasty Register (DKR) has revealed high 2-year revision rates after primary knee arthroplasty performed in 2012 and 2013 in Copenhagen University Hospital Bispebjerg.
Purpose / Aim of Study: To investigate causes of early revisions in order to implement a strategy for improvement of outcome after primary knee arthroplasty.
Materials and Methods: A retrospective single center investigation of all primary knee arthroplasties performed in 2012 and 2013. During the first 15 months the Zimmer NexGen CR-Flex (n=225) was used as the standard primary knee prosthesis and in the remaining 9 months the DePuySynthes SIGMA (n=158) was used. 17 uni- compartmental prosthesis were implanted.
Findings / Results: 197 primary knee arthroplasties were performed in 2012 and 21(10.7%) were revised within 2 years, whereas 203 were performed in 2013 and 22 (10.8%) were revised within 2 years. The main cause of early revision was instability (n=20) resulting in 10 liner exchanges, 3 revisions of femoral component to posterior stabilized and 7 total revision procedures. 6 of the instability cases were fall-related and the remaining 14 were surgical procedure related. Other main causes of early revision were aseptic loosening of the tibial component (n=10) and secondary insertion of patella component (n=4).
Conclusions: Some of the early revisions (liner exchanges) due to instability could be explained by the learning curve after change of the standard prosthesis and a decrease in these revisions are expected with an increased intra- operative focus on balancing. The revisions due to aseptic loosening have led to a change in cementation technique of the tibial component. Finally, patella resurfacing is now performed as a standard procedure. With implementation of these interventions the early revision rate is expected to decrease significantly.
Erik Poulsen, Bent Lund, Ewa M Roos
Department of Sports Science and Clinical Biomechanics, University of Southern Denmark; Department of Orthopaedic Surgery, Horsens Regional Hospital; Department of Sports Science and Clinical Biomechanics, University of Southern Denmark
Background: The Danish Hip Arthroscopy Registry (DHAR) started in 2012 to assist in quality assurance of hip arthroscopy in public and private hospitals.
Purpose / Aim of Study: To describe selected patient reported outcomes (PROMs) at baseline and surgical characteristics.
Materials and Methods: Patient reported data includes the Copenhagen Hip and Groin Outcome Score (HAGOS) the international Hip Outcome Tool – short version (iHOT12), both scoring 0-100, worst to best. Activity level was assessed by the Hip Sports Activity Scale (HSAS). Surgical characteristics include: hip operated on, reoperations, duration of surgery, alpha angle, labrum lesions and cartilage lesions according to the ICRS and Becks classifications.
Findings / Results: As of March 2016, 2508 patients were registered having received hip arthroscopic surgery. Mean age was 37 (range 9-80), 49% were females and 4% were elite athletes while 70% did no or minimal physical activity. From February 2012 to March 2016, a total of 544 (22%) patients were registered having received more than one operation of which 443 (18%) were reoperations. The right to left ratio was 1.17:1. Patient reported outcomes were registered by 1683 patients (67%) and 43 did not consent to entering data. Mean HAGOS subscales were; Pain 49 (SD=19), Symptoms 51 (18), ADL 48 (24), Sport/rec 65 (23), Physical Activity 79 (24) and QoL 71 (16). Mean IHOT12 was 49 (22). Mean duration of surgery was 83 minutes (range 33- 145), mean alpha angle 66, 87% had labral lesions, 29% had cartilage lesions according to ICRS and 98% according to Becks classifications.
Conclusions: Currently 70% of operated patients provide data to the DHAR. The population is young to middle-aged, has on average moderate pain and is largely physically inactive at baseline. The majority of patients have labral and cartilage lesions related to the acetabulum.
Department of Sports Science and Clinical Biomechanics, University of Southern Denmark; Department of Orthopaedic Surgery, Horsens Regional Hospital; Department of Sports Science and Clinical Biomechanics, University of Southern Denmark
Background: The Danish Hip Arthroscopy Registry (DHAR) started in 2012 to assist in quality assurance of hip arthroscopy in public and private hospitals.
Purpose / Aim of Study: To describe selected patient reported outcomes (PROMs) at baseline and surgical characteristics.
Materials and Methods: Patient reported data includes the Copenhagen Hip and Groin Outcome Score (HAGOS) the international Hip Outcome Tool – short version (iHOT12), both scoring 0-100, worst to best. Activity level was assessed by the Hip Sports Activity Scale (HSAS). Surgical characteristics include: hip operated on, reoperations, duration of surgery, alpha angle, labrum lesions and cartilage lesions according to the ICRS and Becks classifications.
Findings / Results: As of March 2016, 2508 patients were registered having received hip arthroscopic surgery. Mean age was 37 (range 9-80), 49% were females and 4% were elite athletes while 70% did no or minimal physical activity. From February 2012 to March 2016, a total of 544 (22%) patients were registered having received more than one operation of which 443 (18%) were reoperations. The right to left ratio was 1.17:1. Patient reported outcomes were registered by 1683 patients (67%) and 43 did not consent to entering data. Mean HAGOS subscales were; Pain 49 (SD=19), Symptoms 51 (18), ADL 48 (24), Sport/rec 65 (23), Physical Activity 79 (24) and QoL 71 (16). Mean IHOT12 was 49 (22). Mean duration of surgery was 83 minutes (range 33- 145), mean alpha angle 66, 87% had labral lesions, 29% had cartilage lesions according to ICRS and 98% according to Becks classifications.
Conclusions: Currently 70% of operated patients provide data to the DHAR. The population is young to middle-aged, has on average moderate pain and is largely physically inactive at baseline. The majority of patients have labral and cartilage lesions related to the acetabulum.
Bo Mussmann, Søren Overgaard, Trine Torfing, Morten Bøgehøj, Oke Gerke, Poul Erik Andersen
Department of Radiology, Odense University Hospital; Department of Orthopedic Surgery and Traumatology, Odense University Hospital; Department of Radiology, Odense University Hospital; Department of Orthopedic Surgery and Traumatology, Odense University Hospital; Department of Nuclear Medicine, Odense University Hospital; Department of Radiology, Odense University Hospital
Background: Periprosthetic bone loss is considered a predictor of aseptic loosening of the acetabular component in total hip arthroplasty. However, no studies have shown this association. This may be explained by imaging methods used. Dual energy CT (DECT) has previously shown better delineation of the interface between bone and prosthesis and may be beneficial in quantitative analysis of bone loss close to the implant as compared to single energy computed tomography (SECT).
Purpose / Aim of Study: To test the agreement and reliability of bone mineral density measurements (BMD) in close proximity of the acetabular cup using SECT and DECT images and 3D segmentation software.
Materials and Methods: 12 un-cemented and 12 cemented cups were inserted in porcine hip specimens ex vivo. A femoral stem was attached to each specimen and imaging was performed with SECT and DECT. The specimens were repositioned and scans repeated to obtain double measurements. For each scan BMD was measured in a hemispherical volume around the acetabular cup using in-house segmentation software.
Findings / Results: In the uncemented concept mean BMD difference between the double measurements in SECT was 8 mg/cm3 (p=0.64) and 2 mg/cm3 in DECT (p=0.596). ICC was 0.90 for SECT and 0.91 for DECT. In the cemented concept the differences were 41 mg/cm3 (p=0.055) and 11 mg/cm3 (p=0.013), respectively, and ICC was 0.74 for SECT and 0.91 for DECT. In both concepts the Bland Altman limits of agreement were wider in SECT (uncemented: -95 to 111; cemented: -107 to 189) compared with DECT (uncemented: -28 to 23; cemented: -20 to 42).
Conclusions: There were no statistically significant reliability differences between SECT and DECT, but results suggest that the agreement of DECT is better than SECT, and both scan modes perform better in the un-cemented concept compared with the cemented concept.
Department of Radiology, Odense University Hospital; Department of Orthopedic Surgery and Traumatology, Odense University Hospital; Department of Radiology, Odense University Hospital; Department of Orthopedic Surgery and Traumatology, Odense University Hospital; Department of Nuclear Medicine, Odense University Hospital; Department of Radiology, Odense University Hospital
Background: Periprosthetic bone loss is considered a predictor of aseptic loosening of the acetabular component in total hip arthroplasty. However, no studies have shown this association. This may be explained by imaging methods used. Dual energy CT (DECT) has previously shown better delineation of the interface between bone and prosthesis and may be beneficial in quantitative analysis of bone loss close to the implant as compared to single energy computed tomography (SECT).
Purpose / Aim of Study: To test the agreement and reliability of bone mineral density measurements (BMD) in close proximity of the acetabular cup using SECT and DECT images and 3D segmentation software.
Materials and Methods: 12 un-cemented and 12 cemented cups were inserted in porcine hip specimens ex vivo. A femoral stem was attached to each specimen and imaging was performed with SECT and DECT. The specimens were repositioned and scans repeated to obtain double measurements. For each scan BMD was measured in a hemispherical volume around the acetabular cup using in-house segmentation software.
Findings / Results: In the uncemented concept mean BMD difference between the double measurements in SECT was 8 mg/cm3 (p=0.64) and 2 mg/cm3 in DECT (p=0.596). ICC was 0.90 for SECT and 0.91 for DECT. In the cemented concept the differences were 41 mg/cm3 (p=0.055) and 11 mg/cm3 (p=0.013), respectively, and ICC was 0.74 for SECT and 0.91 for DECT. In both concepts the Bland Altman limits of agreement were wider in SECT (uncemented: -95 to 111; cemented: -107 to 189) compared with DECT (uncemented: -28 to 23; cemented: -20 to 42).
Conclusions: There were no statistically significant reliability differences between SECT and DECT, but results suggest that the agreement of DECT is better than SECT, and both scan modes perform better in the un-cemented concept compared with the cemented concept.
Anne Soon Bensen, Carsten Jensen, Bo Mussmann, Trine Torfing, Ole Ovesen, Søren Overgaard
Department of Orthopedic Surgery, The Hospital of South-West Jutland; Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Radiology, Odense University Hospital; Department of Radiology, Odense University Hospital; Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Orthopaedic Surgery and Traumatology, Odense University Hospital
Background: Retroversion of the acetabulum is a subgroup within hip dysplasia (HD). For diagnosing several X-rays of the pelvis are required. The EOS 2D Imaging System may be an option. To our knowledge no studies have compared EOS-images of the pelvis with conventional radiographs in a population with retroversion of the acetabulum.
Purpose / Aim of Study: 1) To compare conventional AP-radiographs and EOS of the pelvis with regard to pelvic tilt and acetabular parameters describing acetabular retroversion. 2) To evaluate changes in these parameters when changing from standing to sitting position using EOS.
Materials and Methods: A cohort of 34 subjects with retroversion of the acetabulum on standing AP- radiographs, were included. Two EOS- images of the pelvis in standing and sitting position were obtained. Radiographs and EOS-images were all assessed for radiographic signs of retroverted acetabulum (cross-over-sign, posterior-wall- sign, ischial-spine-sign), center-edge-angle < 25°, acetabular-index > 10°, pelvic tilt, rotation and sagittal pelvic parameters.
Findings / Results: 1) Standing AP-radiographs versus EOS- images showed a significant difference in AP-pelvic tilt due to magnification (p<0001). No difference in any of the other parameters between the two modalities were found. 2) EOS-images showed that the pelvis tilted backwards when subjects were repositioned from standing to sitting. The presence of radiographic signs of retroversion was significantly reduced (p<0.0001) but no significant difference in number of patients with center-edge-angle < 25° or acetabular- index > 10° between the two positions was seen.
Conclusions: Standard X-rays and EOS showed no significant difference. Using EOS pelvic tilt changed significantly from standing to sitting. In perspective: EOS may have the potential to be used to assess acetabular orientation and HD.
Department of Orthopedic Surgery, The Hospital of South-West Jutland; Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Radiology, Odense University Hospital; Department of Radiology, Odense University Hospital; Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Orthopaedic Surgery and Traumatology, Odense University Hospital
Background: Retroversion of the acetabulum is a subgroup within hip dysplasia (HD). For diagnosing several X-rays of the pelvis are required. The EOS 2D Imaging System may be an option. To our knowledge no studies have compared EOS-images of the pelvis with conventional radiographs in a population with retroversion of the acetabulum.
Purpose / Aim of Study: 1) To compare conventional AP-radiographs and EOS of the pelvis with regard to pelvic tilt and acetabular parameters describing acetabular retroversion. 2) To evaluate changes in these parameters when changing from standing to sitting position using EOS.
Materials and Methods: A cohort of 34 subjects with retroversion of the acetabulum on standing AP- radiographs, were included. Two EOS- images of the pelvis in standing and sitting position were obtained. Radiographs and EOS-images were all assessed for radiographic signs of retroverted acetabulum (cross-over-sign, posterior-wall- sign, ischial-spine-sign), center-edge-angle < 25°, acetabular-index > 10°, pelvic tilt, rotation and sagittal pelvic parameters.
Findings / Results: 1) Standing AP-radiographs versus EOS- images showed a significant difference in AP-pelvic tilt due to magnification (p<0001). No difference in any of the other parameters between the two modalities were found. 2) EOS-images showed that the pelvis tilted backwards when subjects were repositioned from standing to sitting. The presence of radiographic signs of retroversion was significantly reduced (p<0.0001) but no significant difference in number of patients with center-edge-angle < 25° or acetabular- index > 10° between the two positions was seen.
Conclusions: Standard X-rays and EOS showed no significant difference. Using EOS pelvic tilt changed significantly from standing to sitting. In perspective: EOS may have the potential to be used to assess acetabular orientation and HD.
Natasja Jørgensen, Morten Foss, Nikolaj Gadegaard, Casper Foldager, Martin Lind, Helle Lysdahl
Ortopædisk forskningslaboratorium , Aarhus Universitetshospital; Interdisciplinary Nanoscience Center, Aarhus Universitet; School of Engineering, Glasgow Universitet; Ortopædisk forskningslaboratorium , Aarhus Universitetshospital; Ortopædisk forskningslaboratorium , Aarhus Universitetshospital; Ortopædisk forskningslaboratorium , Aarhus Universitetshospital
Background: The nature of the surface on which chondrocytes are cultured ex vivo plays an important role for proliferation and differentiation in the field of cartilage regeneration.
Purpose / Aim of Study: We aimed to investigate the behaviour of human chondrocytes on different substrates and surface chemistry.
Materials and Methods: Human chondrocytes were isolated from cartilage biopsies collected from 3 patients. Chondrocytes were seeded with 2,500 cells/cm2 on polystyrene (rigid) or polydimethylsiloxane (soft) with surface chemistry of oxygen plasma (PL) or fibronectin (FN) and cultured for 1, 4, 7, and 10 days. Proliferation, cell viability, cell size, and gene expression were performed using methylene blue staining, XTT assay, actin staining, and RT-qPCR, respectively.
Findings / Results: We found similar proliferative capacity over time for all substrates and surface chemistry. Cell viability was significantly higher on the polystyrene compared with PDMS. For surface chemistry, PL and FN, cell viability was highest in chondrocytes cultured on FN surfaces. The cytoskeleton of chondrocytes on FN was associated with chondrocyte size > 2000 μm2 compared with PL where chondrocyte sizes were < 1000 μm2. For substrates, we found significantly higher expression of SOX9 and COL2A1 in chondrocytes cultured on PDMS compared with polystyrene. For surface chemistry, chondrocytes cultured on PL had significantly higher SOX9, COL2A1, ACAN expression compared with FN.
Conclusions: Cultivation of human chondrocytes on soft PMDS coated with PL resulted in chondro- inductive conditions having the lowest cell viability, smallest cell size, and the highest expression of cartilage specific genes. Constituting further investigations aiming at elucidating the role of a softer culture substrate when culturing human chondrocytes ex vivo.
Ortopædisk forskningslaboratorium , Aarhus Universitetshospital; Interdisciplinary Nanoscience Center, Aarhus Universitet; School of Engineering, Glasgow Universitet; Ortopædisk forskningslaboratorium , Aarhus Universitetshospital; Ortopædisk forskningslaboratorium , Aarhus Universitetshospital; Ortopædisk forskningslaboratorium , Aarhus Universitetshospital
Background: The nature of the surface on which chondrocytes are cultured ex vivo plays an important role for proliferation and differentiation in the field of cartilage regeneration.
Purpose / Aim of Study: We aimed to investigate the behaviour of human chondrocytes on different substrates and surface chemistry.
Materials and Methods: Human chondrocytes were isolated from cartilage biopsies collected from 3 patients. Chondrocytes were seeded with 2,500 cells/cm2 on polystyrene (rigid) or polydimethylsiloxane (soft) with surface chemistry of oxygen plasma (PL) or fibronectin (FN) and cultured for 1, 4, 7, and 10 days. Proliferation, cell viability, cell size, and gene expression were performed using methylene blue staining, XTT assay, actin staining, and RT-qPCR, respectively.
Findings / Results: We found similar proliferative capacity over time for all substrates and surface chemistry. Cell viability was significantly higher on the polystyrene compared with PDMS. For surface chemistry, PL and FN, cell viability was highest in chondrocytes cultured on FN surfaces. The cytoskeleton of chondrocytes on FN was associated with chondrocyte size > 2000 μm2 compared with PL where chondrocyte sizes were < 1000 μm2. For substrates, we found significantly higher expression of SOX9 and COL2A1 in chondrocytes cultured on PDMS compared with polystyrene. For surface chemistry, chondrocytes cultured on PL had significantly higher SOX9, COL2A1, ACAN expression compared with FN.
Conclusions: Cultivation of human chondrocytes on soft PMDS coated with PL resulted in chondro- inductive conditions having the lowest cell viability, smallest cell size, and the highest expression of cartilage specific genes. Constituting further investigations aiming at elucidating the role of a softer culture substrate when culturing human chondrocytes ex vivo.
Kristoffer Weisskirchner Barfod
OrthoSport Victoria Research Unit, Deakin University and Epworth HealthCare, Australia
Background: Restoration of muscle strength after anterior cruciate ligament (ACL) tear is considered important in order to safely return to sport, but comprehensive strength testing protocols are often very time-consuming.
Purpose / Aim of Study: The purpose of the study was to improve the efficiency of a strength testing protocol by investigating if some tests are redundant and could be omitted when evaluating outcomes at 6 and 12 month following ACL reconstruction.
Materials and Methods: The study was performed as a prospective cohort study following the STROBE guidelines. The following 4 strength tests were performed using a HUMAC NORM Dynamometer: 1. Isokinetic concentric strength at 60°/s, 2. Isokinetic concentric strength at 180°/s, 3. Isometric strength, and 4. Isokinetic eccentric strength at 60°/s. The redundancy of strength tests was investigated by fitting a linear regression model to the data. An R-squared value above 0.75 was chosen to indicate redundancy.
Findings / Results: The cohort consisted of 123 patients (74 male, 49 female) who completed 6 and 12 months follow up after ACLR. The comparison of concentric peak force at 60deg/s and 180deg/s showed redundancy at both 6 and 12 months when looking at the limbs separately (R2=0.775 to 0.861). The comparison of isometric and isokinetic peak force and concentric and eccentric peak force often showed borderline redundancy (R2=0.574 to 0.806). No analyses of limb symmetry index showed redundancy.
Conclusions: At 6 and 12 month following ACL reconstruction little extra information was generated by testing concentric strength at both 60deg/s and 180deg/s, as the measurements showed considerable redundancy with one explaining approximately 90% of the other. To achieve a more time-efficient testing protocol only one concentric speed should be included.
OrthoSport Victoria Research Unit, Deakin University and Epworth HealthCare, Australia
Background: Restoration of muscle strength after anterior cruciate ligament (ACL) tear is considered important in order to safely return to sport, but comprehensive strength testing protocols are often very time-consuming.
Purpose / Aim of Study: The purpose of the study was to improve the efficiency of a strength testing protocol by investigating if some tests are redundant and could be omitted when evaluating outcomes at 6 and 12 month following ACL reconstruction.
Materials and Methods: The study was performed as a prospective cohort study following the STROBE guidelines. The following 4 strength tests were performed using a HUMAC NORM Dynamometer: 1. Isokinetic concentric strength at 60°/s, 2. Isokinetic concentric strength at 180°/s, 3. Isometric strength, and 4. Isokinetic eccentric strength at 60°/s. The redundancy of strength tests was investigated by fitting a linear regression model to the data. An R-squared value above 0.75 was chosen to indicate redundancy.
Findings / Results: The cohort consisted of 123 patients (74 male, 49 female) who completed 6 and 12 months follow up after ACLR. The comparison of concentric peak force at 60deg/s and 180deg/s showed redundancy at both 6 and 12 months when looking at the limbs separately (R2=0.775 to 0.861). The comparison of isometric and isokinetic peak force and concentric and eccentric peak force often showed borderline redundancy (R2=0.574 to 0.806). No analyses of limb symmetry index showed redundancy.
Conclusions: At 6 and 12 month following ACL reconstruction little extra information was generated by testing concentric strength at both 60deg/s and 180deg/s, as the measurements showed considerable redundancy with one explaining approximately 90% of the other. To achieve a more time-efficient testing protocol only one concentric speed should be included.
Martin Albert Lundorff, Bent Lund
Department of Orthopaedics , Horsens Regional Hospital HEH; Department of Orthopaedics , Horsens Regional Hospital HEH
Background: Arthroscopic reconstruction of the anterior cruciate ligament (ACL-R) is an established treatment for rupture of the ACL. In Denmark there are more than 2200 primary ACL-R each year. At the 1-year postoperative follow-up one performs a series of measurements in order to assess the progress of the patients and their symptoms. To have a uniform follow-up, all centres report to the Danish National ACL- registry. A quality indicator is 1-year follow- up and the cut-of is a 60% minimum. Many centres, including HEH, have problems living up to this indicator. At HEH the numbers were 52,9% in 2012 and 63,0% in 2013.
Purpose / Aim of Study: The aim of this study is to examine the 1- year follow-up at HEH and possible reasons for lack of achieving this goal. Our hypothesis is that the patient’s follow-up is possibly lost due to poor registration, rebooking, cancellation, reoperation or no- show.
Materials and Methods: Reviewing local ACL-R patient registry examining our follow-up (2012-14).
Findings / Results: We included 180 patients (2012-14) that had a primary ACL-R. We found that 149 patients (82.8%) were seen for 1-year follow-up. 21 patients (14%) had been registered wrongly as they had been examined by a surgeon instead of a physiotherapist. Thus they were not registered in the ACL-registry. 31 patients (17.2%) were not seen for 1-year follow-up. 16 (8,8%) because they were not called in. 15 (8.3%) got called in but did not show up either due to rebooking, cancellation, reoperation or no-show.
Conclusions: We have highlighted possible causes for missing 1-year follow-up for our ACL-R patients and why we do not score higher in the registry on this indicator. The results show that with an optimization in the registration and booking of these patients, we will be able ensure that more patients are assessed at their 1-year follow-up.
Department of Orthopaedics , Horsens Regional Hospital HEH; Department of Orthopaedics , Horsens Regional Hospital HEH
Background: Arthroscopic reconstruction of the anterior cruciate ligament (ACL-R) is an established treatment for rupture of the ACL. In Denmark there are more than 2200 primary ACL-R each year. At the 1-year postoperative follow-up one performs a series of measurements in order to assess the progress of the patients and their symptoms. To have a uniform follow-up, all centres report to the Danish National ACL- registry. A quality indicator is 1-year follow- up and the cut-of is a 60% minimum. Many centres, including HEH, have problems living up to this indicator. At HEH the numbers were 52,9% in 2012 and 63,0% in 2013.
Purpose / Aim of Study: The aim of this study is to examine the 1- year follow-up at HEH and possible reasons for lack of achieving this goal. Our hypothesis is that the patient’s follow-up is possibly lost due to poor registration, rebooking, cancellation, reoperation or no- show.
Materials and Methods: Reviewing local ACL-R patient registry examining our follow-up (2012-14).
Findings / Results: We included 180 patients (2012-14) that had a primary ACL-R. We found that 149 patients (82.8%) were seen for 1-year follow-up. 21 patients (14%) had been registered wrongly as they had been examined by a surgeon instead of a physiotherapist. Thus they were not registered in the ACL-registry. 31 patients (17.2%) were not seen for 1-year follow-up. 16 (8,8%) because they were not called in. 15 (8.3%) got called in but did not show up either due to rebooking, cancellation, reoperation or no-show.
Conclusions: We have highlighted possible causes for missing 1-year follow-up for our ACL-R patients and why we do not score higher in the registry on this indicator. The results show that with an optimization in the registration and booking of these patients, we will be able ensure that more patients are assessed at their 1-year follow-up.