Sports Orthopaedics

111. CARGEL Bioscaffold Improves Cartilage Repair Tissue after Bone Marrow Stimulation in a Minipig Model
Kris Hede, Bjørn Borsøe Christensen, Morten Lykke Olesen, Jesper Skovhus Thomsen, Casper Bindzus Foldager, Martin Lind
Orthopaedic Research Lab, Aarhus University Hospital; Department of Orthopaedics, Aarhus University Hospital; Orthopaedic Research Lab, Aarhus University Hospital; Department of Biomedicine, Aarhus University; Department of Orthopaedics, Aarhus University Hospital; Department of Orthopaedics, Aarhus University Hospital


Background: Recently several microfracture enhancement treatments have been developed to improve the cartilage repair after microfracture treatment. One such already clinically used enhancer is the Cargel Bioscaffold (CB) which is based on chitosan.
Purpose / Aim of Study: To gain knowledge of the repair tissue of cartilage repair using bone marrow stimulation combined with CARGEL Bioscaffold compared with bone marrow stimulation (BMS) alone in chondral defects in a validated animal model.
Materials and Methods: Six adult Göttingen minipigs received two chondral defects in each knee. The knees were randomized to BMS combined with CB or BMS alone. The animals were euthanized after 6 months. Follow-up consisted of histomorphometry, immunohistochemistry, semiquantitative scoring of the repair tissue (ICRS II), and µCT of the trabecular bone beneath the defect.
Findings / Results: There was significantly more fibrocartilage (80% vs 64%, p = 0.04) and a trend towards less fibrous tissue (15% vs 30%, p = 0.05) in the defects treated with CB. Hyaline tissue was only seen in one defect treated with CB and none treated with BMS alone. For histological semiquantitative score (ICRS II), defects treated with CB scored lower on subchondral bone (69 vs. 44, p = 0.04). No significant differences were seen on the other parameters of the ICRS II. Collagen type II staining revealed a trend towards more positive staining in the CB group (p = 0.08). µCT revealed thicker trabeculae (p = 0.029) and a higher bone material density (p = 0.028) in defects treated with CB.
Conclusions: Treatment of cartilage injuries with CARGEL Bioscaffold seems to lead to an improved repair tissue and a more pronounced subchondral bone response compared with bone marrow stimulation alone, however the treatment did not lead to formation of hyaline cartilage.

112. Knee muscle strength in patients undergoing ACL reconstruction using either knee extensor or flexor graft: a systematic review of randomized controlled trials.
Bo Bregenhof, Anders Holsgaard-Larsen, Jonas Bloch Thorlund, Carsten Jensen, Maria Thorning, Per Aagaard, Carsten Bogh Juhl
Orthopaedic Research Unit, Department of Clinical Research, University of Southern Denmark , Department of Orthopaedics and Traumatology, Odense University Hospital, Denmark; Orthopaedic Research Unit, Department of Clinical Research, University of Southern Denmark , Department of Orthopaedics and Traumatology, Odense University Hospital, Denmark; Department of Sports Science and Clinical Biomechanics, University of Southern Denmark; Department of Orthopaedic Surgery and Traumatology, Lillebaelt Hospital - University Hospital of Southern Denmark, Denmark, Institute of Regional Health Research, University of Southern Denmark, Denmark; Department of Neurology, Department of Orthopeadics and Traumatology, Department of Molecular Medicine, University of Southern Denmark , Odense University Hospital, Denmark; Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, ; Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Department of Physiotherapy and Occupational Therapy, Copenhagen University Hospital, Herlev and Gentofte, Denmark


Background: Anterior cruciate ligament reconstruction (ACLR) may lead to persistent muscle strength deficiency for more than one year after ACLR, increasing the risk of developing knee osteoarthritis. Common harvest techniques include the Quadriceps tendon (QT), bone-patellar tendon-bone (BPTP) or Hamstring (HS) tendon. Previous systematic reviews have reported reduced knee extensor and knee flexor strength in the ACLR limb compared to the non-operated limb, depending on graft type. However, several randomized controlled trials (RCT) on the subject have since been published.
Purpose / Aim of Study: The aim was to determine short- and long-term deficits in knee flexor and extensor strength following ACLR using either QT/BPTB or HS graft, at 6, 12, 24 and +48 months, post-surgery.
Materials and Methods: A comprehensive literature search for RCTs comparing muscle strength deficits after QT/BPTP and HS graft after ACLR was performed in MEDLINE, EMBASE and CENTRAL. Risk of bias was assessed using the Cochrane risk-of-bias tool (RoB.2). GRADE guidelines for measuring the overall study quality were applied. Results were pooled using a random effect meta-analysis. PROSPERO Reg. nr: CRD42018068351
Findings / Results: Twenty-six studies, evaluating 1017 and 1050 ACLR patients with the PT/BPTB or HS graft, respectively were included. Studies revealed significant limb-to-limb strength deficits of both the knee flexors and extensors after ACLR. QT/BPTP showed extension deficits of 24% (SE: 5.1) at 6 months post-surgery, resolving over time to 16% (6.7), 9% (5.8) and 9% (5.8) at 12, 24 and +48 months. The corresponding values for flexion deficit were 8% (5.2), 5% (5.3), 5% (5.3) and 5% (5.3). HS showed extension deficits of 15% (5.4) at 6 months post-surgery, resolving to 10% (6.1), 8% (4.4) at 12, 24 and +48 months. The corresponding values for flexion deficits were 16% (5.6), 10% (5.3) and 6% (5.3) at 12, 24 and +48-months, respectively.
Conclusions: The available evidence suggest that lower limb muscular strength deficits persist one year or longer after ACLR. Use of QT/BPTB grafts showed substantially higher knee extensor strength deficits compared to HS grafts in the early post-surgical phase which resolved over time. Thus, the graft types were deemed comparable.

113. Danish version of the Western Ontario Meniscal Evaluation Tool (WOMET): a cross-cultural adaptation, test-retest reliability and responsiveness study
Jon Martin Clementsen, Søren T. Skou, Sascha Lohse Hansen, Henrik Eshøj, Carsten Møller Mølgaard, Lone Ramer Mikkelsen, Jonas B. Thorlund
Elective Surgery Centre, Silkeborg Regional Hospital; Department of Sports Science and Clinical Biomechanics, University of Southern Denmark; Department of Sports Science and Clinical Biomechanics, University of Southern Denmark; Department of Sports Science and Clinical Biomechanics, University of Southern Denmark; Department of Occupational Therapy and Physiotherapy, Aalborg University Hospital; Elective Surgery Centre, Silkeborg Regional Hospital; Department of Sports Science and Clinical Biomechanics, University of Southern Denmark


Background: The Western Ontario Meniscal Evaluation Tool (WOMET) is a widely used Patient Reported Outcome Measure (PROM) designed to evaluate Health Related Quality of Life (HRQOL) in patients with meniscal injuries.
Purpose / Aim of Study: The purpose of this study was to translate and cross-culturally adapt the WOMET for use in the Danish speaking population and evaluate its test- retest reliability and comparative responsiveness.
Materials and Methods: The WOMET consists of 3 subscales (physical symptoms, sports/recreation/work/lifestyle and emotions) and the total score range from 0-1600 (0=best and 1600=worst). It was forward and backward translated into Danish according to international guidelines. 60 patients (mean age 49 years (range 19-71 years), 57% females) with meniscal injury scheduled for arthroscopy meniscal surgery at Silkeborg Regional Hospital, in the period from September 2017 to February 2018, were included in this study. The WOMET was completed at 3 time points, at baseline, at 3- and 6-months postoperatively. Additionally, test- retest reliability was assessed at 3-months and at 3-months plus one week, in 55 patients with stable symptom state from test to retest assessed with a Global Response Question. Comparative responsiveness was assessed between the WOMET and The Knee injury and Osteoarthritis Outcome Score (KOOS4 – an aggregate score of 4 of the 5 KOOS subscales, excluding the activities of daily living subscale).
Findings / Results: The Danish version of the WOMET was successfully translated and showed good face validity. Test-retest reliability was excellent, with Intra Class Correlation (ICC) of 0.88 (95%CI 0.84- 0.92) for the total score. The Standard Error of Measurement (SEM) was 125 points and the Minimal Detectable Change (MDC) was 347 points (i.e., 7.8% and 21.7% of the total score, respectively. No floor or ceiling effects was observed. The WOMET had good responsiveness with an effect size (ES) of 1.12 at 6 months after surgery, which was comparable to the KOOS4 (ES 1.10).
Conclusions: The Danish version of the WOMET is reliable and responsive for assessing health-related quality of life in patients with meniscal pathology.

114. Hip kinematics and kinetics in patients with femoroacetabular impingement syndrome before and one year after hip arthroscopic surgery
Signe Kierkegaard, Inger Mechlenburg, Ulrik Dalgas, Bent Lund, Kjeld Søballe, Henrik Sørensen
Orthopaedics and Physio and Occupational Therapy, Horsens Hospital; Clinical Medicine and Orthopaedics, Aarhus University and Aarhus University Hospital; Section for Sports Science, Department of Public Health, Aarhus University; Orthopaedics, Horsens Hospital; Clinical Medicine and Orthopaedics, Aarhus University and Aarhus University Hospital; Section for Sports Science, Department of Public Health, Aarhus University


Background: Patients with femoroacetabular impingement syndrome (FAIS) experience decreased function. Consequently, earlier studies have evaluated gait biomechanics in these patients, but a larger study evaluating gait biomechanics before and after an intervention standardizing gait speed is lacking.
Purpose / Aim of Study: To investigate gait kinematics and kinetics in patients with FAIS compared with pain-free controls before and one year after surgery. Secondary, we aimed at analyzing gait pattern separately for sex and to investigate associations between peak kinematics and kinetics and the Copenhagen Hip and Groin Outcome Score (HAGOS).
Materials and Methods: Sixty patients with FAIS and 30 pain-free controls were tested at a standardized gait speed (1.40 m/s ±10%). Patients were tested twice: before and one year after surgery. Kinematics and kinetics were recorded using infrared high-speed cameras and a force plate. Participants answered HAGOS.
Findings / Results: The largest difference among groups was that gait differed between males and females. Neither before nor after surgery could we demonstrate large alterations in gait pattern between patients and pain-free controls. Male patients demonstrated associations between peak kinematics and kinetics and HAGOS Sports function.
Conclusions: Gait pattern was only vaguely altered in patients with FAIS compared with pain-free controls before and after surgery when using at standardized gait speed. Hence, analyzing gait in patients with FAIS does not seem of major importance. Nevertheless, there was an association between HAGOS Sports function and peak kinematics and kinetics in male patients implying that there could be a clinical importance.

115. Intra-day and Inter-day reliability and validity of the Reactive Strength Index derived from unilateral drop jumps measured on the My Jump 2 app and a force platform
Kasper Krommes, Jesper Dyhr, Vibberstoft Thomas, Asger Møller, Nielsen Nedergaard, Jesper Bencke, Kristian Thorborg, Per Hölmich, Ishøi Ishøi
Orthopedic Department, Sports Orthopedic Research Center - Copenhagen, Hvidovre Hospital; Bachelor's Degree Programme in Physiotherapy, Faculty of Health and Technology, University College Copenhagen; Bachelor's Degree Programme in Physiotherapy, Faculty of Health and Technology, University College Copenhagen; Orthopedic Department, Sports Orthopedic Research Center - Copenhagen, Hvidovre Hospital; Orthopedic Department, Human Movement Analysis Laboratory, Hvidovre Hospital; Orthopedic Department, Human Movement Analysis Laboratory, Hvidovre Hospital; Orthopedic Department, Sports Orthopedic Research Center - Copenhagen, Hvidovre Hospital; Orthopedic Department, Sports Orthopedic Research Center - Copenhagen, Hvidovre Hospital; Orthopedic Department, Sports Orthopedic Research Center - Copenhagen, Hvidovre Hospital


Background: The unilateral drop jump has been proposed as a test for measuring single-limb reactive strength index (RSI), a metric for the ability to rapidly absorb and produce force. RSI is considered important for performance and for guiding rehabilitation in athletes and physically active patients. RSI can be obtained clinically using a simple smartphone app based in video analysis. However, no data exists on the reliability or validity of deriving single- limb RSI from the MyJump2 application.
Purpose / Aim of Study: This study aims to investigate the reliability and validity of MyJump2 compared to a force platform, when measuring
Materials and Methods: Thirty-seven participants (Tegner >5) aged 18-35 years attended two sessions and performed UDJs from three different box heights (15, 20, 25 cm) down onto a force plate in a random order whilst being recorded on a smartphone camera. Minimal detectable change (MDC) was established, and Bland-Alman plots and ICC (intraclass correlation coefficient) scores between instruments were examined for systematic bias.
Findings / Results: Excellent validity was found across all three heights; 15, 20 and 25 cm, respectively (ICC = 0.986, 95%CI:0.976-0.989, p<0.001). However, MyJump2 underestimated the RSI by approximately 0.05 RSI. Inter-rater reliability within MyJump2 showed excellen to near to perfect correlation (ICC = 0.989, 95%CI:0.952- 0.996, p<0.001). Intra-day reliability showed moderate-excellent correlation across all three heights (ICC = 0.810-0.887, p<0.001). Inter-day reliability showed moderate-excellent correlation across all three heights (ICC = 0.805-0.865, p<0.001). Low SB was found between the two instruments. The MDC of the RSI extracted from MyJump2 ranged 0.08-0.18 (10.4-24.25%), with the 25 cm box height having the lowest MDC.
Conclusions: MyJump2 app is valid and reliable compared to a force platform when measuring the RSI of UDJs from different jump heights. The 25 cm box height had the best results indicating that this height would be the best option when testing UDJs. Systematic bias is present between the app and force platform; therefore, practitioners should not compare results across these two instruments.

116. Adaptation and validation of FASH (Functional Assessment Scale for Acute Hamstring injuries) questionnaire for Danish-speaking football players
Anton Alexander Peterlin Peterlin, Stig Brorson, Jonas Vestergaard Iversen
Department of Orthopaedic Surgery, Zealand University Hospital, Koege, Denmark; Department of Orthopaedic Surgery, Zealand University Hospital, Koege, Denmark; Department of Orthopaedic Surgery, Gildhoej Privathospital


Background: The FASH questionnaire is a valid and reliable patient reported outcome measure (PROM) for evaluating pain and functional status of athletes suffering from an acute hamstring muscle injury (AHI).
Purpose / Aim of Study: The aim was to translate and adapt FASH cross- culturally with validity and reliability testing for Danish-speaking footballers suffering from AHI.
Materials and Methods: Translation and following cross-cultural adaptation was done according to guidelines by Beaton et al. The final Danish version (FASH-DK) accepted by the original authors was tested for reliability and validity on 11 footballers with hamstring injuries and 70 asymptomatic controls.
Findings / Results: Healthy controls and AHI patients had mean FASH- DK scores of 95 (SD 6.1) and 40.5 (SD 17.3) respectively. Validity was demonstrated by a significant difference between AHI patients and healthy controls (p < 0.001). Concurrent validity displayed no statistical difference between the original (p = 0.14 AHI; p = 0.88 healthy) or the German questionnaire (p = 0.35 AHI; p = 0.94 healthy) and that of the Danish FASH. FASH-DK demonstrated good to excellent test-retest reliability (ICC = 0.93 with a 95% confidence interval 0.84 - 0.97 and a Spearman’s rho r = 0.91. Internal consistency was excellent (α = 0.97).
Conclusions: FASH-DK is a valid and reliable instrument shown compatible to the original version. It is useful to assess and determine the severity of AHI in Danish footballers, both for researchers and clinicians.

117. Assessment of maximal and explosive muscle strength during hip adduction squeeze and hip abduction press test: An intra- and inter-tester reliability study using a hand-held dynamometer
Asger m. Nielsen, Lasse Ishøi, Laura Krohn, Mette k. Zebis, Lars Louis Andersen, Kristian Thorborg, Mikkel Bek Clausen
Sports Orthopedic Research Center – Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital, Amager-Hvidovre, Denmark; Sports Orthopedic Research Center – Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital, Amager-Hvidovre, Denmark; Sports Orthopedic Research Center – Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital, Amager-Hvidovre, Denmark; Department of Physiotherapy, ; Faculty of Health and Technology, University College Copenhagen, Copenhagen, Denmark, National Research Centre for the Working Environment DK-2100 Copenhagen, Denmark; Sports Orthopedic Research Center – Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital, Amager-Hvidovre, Denmark; Department of Midwifery, Physiotherapy, Occupational Therapy and Psychomotor Therapy, Faculty of Health, University College Copenhagen


Background: Assessment of hip adduction and abduction isometric peak torque and rate of torque development are important when assessing and monitoring athletes with groin pain. Such measures can be easily obtained using the long- lever hip adduction squeeze test and the bilateral hip abduction press test, both with a handheld dynamometer. However, data is lacking on the intra- and inter-tester reliability.
Purpose / Aim of Study: The purpose was to investigate the intra- and inter-tester reliability of maximal torque exertion and the ability to exert torque rapidly obtained during the hip adduction long lever squeeze test and a bilateral hip abduction press test using a hand-held dynamometer.
Materials and Methods: Forty-nine healthy subjects (39 males, 24 years (SD 4) were included for intra- (n=20) and inter- tester reliability (n=29). Subjects performed the hip adduction long lever squeeze test and the bilateral hip abduction press test in a randomized order. Isometric peak torque and early (0-100 ms) and late (0-200 ms) phase rate of torque development were obtained using a hand-held dynamometer. Relative reliability was assessed for all tests using ICC2,1 two-way mixed model - absolute agreement, thereby taking any bias between testers into account.
Findings / Results: Assessment of peak torque showed good intra- and inter-tester reliability for adduction (ICC: 0.93-0.97) and abduction (ICC: 0.88-0.92). For 0-200 ms rate of torque development, both tests showed good intra-tester reliability (ICC: 0.85- 0.87), whereas intertester reliability was good for hip adduction squeeze (ICC: 0.75) and moderate for hip abduction press (ICC: 0.71). For 0-100 ms rate of torque development, the hip abduction press test showed good intra- tester reliability (ICC: 0.78). Remaining tests for intra- and inter-tester reliability showed moderate reliability (ICC: 0.50-0.71).
Conclusions: Assessment of isometric peak torque in hip adduction squeeze and abduction press test showed good intra- and inter-tester reliability, whereas 0-200 ms rate of torque development demonstrated good intra-tester reliability. Therefore, measures of hip torque development should preferably be conducted by the same tester, while this is less important for measures of isometric peak torque.

118. Long term outcome of combined bone and cartilage chips transplantation for osteochondral lesions
Bjørn Borsøe Christensen, Morten Lykke Olesen, Kris Chadwick Hede, Jonas Jensen, Martin Lind
Ortopædkirurgisk afdeling, Aarhus Universitetshospital; Ortopædkirurgisk afdeling, Regionshospitalet Horsens; Ortopædkirurgisk forskningslaboratorium, Aarhus Universitetshospital; Radiologisk Afdeling, Aarhus Universitetshospital; Ortopædkirurgisk afdeling, Aarhus Universitetshospital


Background: Osteochondral injuries have proved difficult to treat. There are several treatments available, but no gold standard treatment exists.
Purpose / Aim of Study: We present long term data on a one-step, combined autologous bone and articular cartilage chips transplantation, Autologous Dual-Tissue Transplantation (ADTT). The aim of this study was to investigate the long- term results using MRI, CT and patient reported outcome of ADTT.
Materials and Methods: Eight patients (age 32 ± 7.5 years) suffering from osteochondritis dissecans in the knee were included. There were no control group. The lesion was debrided and the osteochondral defect was filled with autologous bone, to a level at the base of the adjacent cartilage. Cartilage from the intercondylar notch was chipped using a scalpel and embedded in fibrin glue in the defect. Radiologic evaluation was performed using MRI and CT preoperatively, at 1 and at 6 years, and patient reported outcome scores were used to assess subjective and functional clinical outcome preoperatively and at 1, 2 and 5 years (IKDC, KOOS and Tegner activity score).
Findings / Results: The preoperative IKDC score increased from 35.9 to 68.1, 75.4 and 78.2 after 1, 2 and 5 years (p<0.01). The Tegner score improved from 2.5 to 4.7, 5.1 and 5.1 at 1, 2 and 5 years (p<0.05). KOOS subscores Sport/rec, and quality of life improved at 1 year and the improvements persisted at 2 and 5 years (p<0.05). KOOS pain improved after 5 years (p<0.01). Cartilage tissue repair evaluated using MOCART score improved from 22.5 to 52.5 at 1 year (p<0.01). There was a slight deterioration at 6 years (not statistically significant). CT imaging demonstrated good subchondral bone healing at 1 year, with an avg defect bone filling of 75%. At 6 years CT showed an improvement in all patients with an average bone filling of 90% and a more even surface than at 1 year.
Conclusions: Treatment of osteochondral defects with ADTT resulted in very good subchondral bone restoration and good cartilage repair. Significant improvements in patient reported outcome was found at 1 year postoperative and the improvements persisted at 2 and 5 years. This study suggests ADTT as a promising, low-cost, treatment for osteochondral injuries.

119. High revision rate after quadriceps tendon graft use for anterior cruciate ligament reconstruction is associated with surgical activity of clinics. Results from the Danish Knee Ligament Reconstruction Registry
Martin Lind, Torsten Nielsen
Orthopedics, Aarhus University Hospital; Orthopedics, Aarhus University Hospital


Background: Quadriceps tendon (QT) has recently gained increase interest as ACL reconstruction (ACLR) graft due to introduction of minimal invasive harvesting techniques and low donor site morbidity. Recent Danish registry data have demonstrated surprizing higher revision rate of 4.7 % for QT graft compared to hamstring (HT) and patella tendon (PT) graft. The influence of individual department/clinic routine for the procedure could be an important factor for revision outcome.
Purpose / Aim of Study: The purpose of the present study is to use the Danish Knee Ligament Reconstruction Registry (DKRR) to compare revision rates in patients who have undergone ACLR with QT, HT, and PT as graft for ACLR related to individual clinic surgical activity. It was hypothesized that low clinic volume of the new QT grafts would result in higher revision rates compared to high volume clinics.
Materials and Methods: Data on primary ACLRs in the DKRR from 2012 through 2019 were analyzed since QT graft usage started in 2012. Revision rates for QT, HT, and PT grafts were compared according to clinic activity (0-100 procedures) and (> 100 procedures). Revisions rates for the three autograft cohorts are presented as well as adjusted revision hazard rates.
Findings / Results: QT revision rate for low activity clinics (0- 100 procedures) was 5.1 % which was significantly higher than a rate of 2.0 % for high activity clinics. (p = 0.003) Adjusted revision hazard rate for low 0-100 group was 2.0 (P=0.01). HT revision rate for clinics (0-100 procedures) was 1.9 % and 2.3 % for > 100 procedure clinics. (ns). PT revision rate for low activity clinics (0-100 procedures) was 3.2 % and 2.2 % for high activity clinics. (ns).
Conclusions: Quadriceps tendon autografts for ACLR was associated with higher revision rates in clinics with lower than 100 procedures performed from 2012-2019. Learning curve and surgical routine appears to account for the previously demonstrated high revision rate for QT graft ACLR in Denmark compared to HT and PT grafts.

120. Translated and locally adapted versions of PROMs are often of questionable quality and there are many undocumented versions
Michael Rindom Krogsgaard, John Brodersen, Karl Bang Christensen, Volkert Siersma, Jonas Jensen, Christian Fugl Hansen, Jonathan David Comins
Section for Sports Traumatology M51, Bispebjerg and Fredeiksberg Hospital; (2) The Research Unit for General Practice and Section for General Practice, Department of Public Health, University of Copenhagen & Primary Health Care Research Unit, Region Zealand, Denmark; (3) Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark; (2) The Research Unit for General Practice and Section for General Practice, University of Copenhagen ; Section for Sports Traumatology M51, Bispebjerg an Frederiksberg Hospital; Section for Sports Traumatology M51, Bispebjerg and Frederiksberg Hospital; Section for Sports Traumatology M51, Bispebjerg and Frederiksberg Hospital


Background: If a good PROM exists in one language, it is convenient to translate this PROM instead of developing a new one in another language. However, translation may alter the meaning of items and thereby the psychometric properties of the PROM. Hence, translation has to be structured in order to achieve proper adaptation to a new culture.
Purpose / Aim of Study: The aims were to assess how the most commonly used PROMs in sports research had been translated, culturally adapted and validated, including assessment of differential item functioning (DIF) locally and between versions.
Materials and Methods: For 392 translated versions of 61 different PROMs identified by search in PubMed and SCOPUS, the methods for translation, cultural adaption and construct validation were assessed. Information about translated versions were obtained from the homepages of commonly used PROMs and compared to the translations that could be identified in literature.
Findings / Results: 94% of all translations had been performed with forward-backwards technique, but only 49% used cognitive interviews to ensure appropriate wording, understandability, and adaption to the local culture with patients and laypersons. Only 2% of the translated versions were validated according to modern test theory models, and no study assessed differential item functioning (DIF) for the local PROM or cross-cultural DIF. For PROMs that were not developed in English language, it was common that translations to other languages were based on undocumented English versions. Many translated versions of commonly used PROMs were undocumented.
Conclusions: A majority of translated PROMs are of questionable quality, despite the common conclusion that the actual PROM is a valid and reliable measurement tool.

121. Sterno-clavicular arthroscopy is a safe and effective procedure – experience with 67 cases
Michael Rindom Krogsgaard, Martin Rathcke
Section for Sports Traumatology, Bispebjerg and Frederiksberg Hospital; Section for Sports Traumatology, Bispebjerg and Frederiksberg Hospital


Background: Advantages of arthroscopy of the sternoclavicular joint (SCJ) is a better visualization and lower surgical morbidity. However, there are only few, small treatment series reported in literature.
Purpose / Aim of Study: To report a prospective, consecutive series of SCJ-arthroscopies.
Materials and Methods: In 67 patients with pain from the SCJ we found indication for the procedure. All cases were unilateral, and we used the same arthroscopic technique in all (published earlier). Patients completed DASH and Oxford Shoulder Score (OSS) before the operation and at 1, 2 and 5 years. Complications and reoperations were recorded.
Findings / Results: In twelve of the 67 cases it was not possible to insert the scope to the joint: two joints turned out to be anchylotic, in one case the subcutaneous fat was extensive making portal positioning unsafe, and in nine osteophytes blocked for the scope. These cases were converted to open surgery. In two cases open resection of osteophytes at the costoclavicular ligament was added to arthroscopy of the joint. In the majority the degenerated or torn disc was resected, and cartilage was debrieded/medial clavicle end resected. In two cases the disc was sutured and in three loose bodies were removed. There were no infections, no per- or post-operative bleedings and no case of penetration of the posterior capsule. Two cases needed re-arthroscopy with further resection of the clavicle. In one case instability occurred after resection of osteophytes and was treated with a stabilizing procedure. In one case an interposition plasty with a gracilis tendon was performed for persisting pain despite resection of the medial clavicle end. DASH score decreased from median 54 (range 30-94) preoperatively, to 37.5 (24-108)(p<0.05) at 1 year and 36 (24-102) at 2 years follow-up. Worst pain item from OSS decreased from mean 2,6 preoperatively to 1,9 at 1 year (p<0.05) and 1,7 at 2 years. Usual pain-item decreased from 2,2 preoperatively to 1,4 at 1 year (p < 0.05) and 1,1 at 2 years. Pain at night decreased from 2,4 preoperatively to 1,3 at 1 year (p<0,05) and 1,4 at 2 years.
Conclusions: SCJ arthroscopy was safe and the clinical results were comparable to or better than reported results of similar open procedures.

122. Satisfying validity of four out of six diagnosis codes for sports related injuries concerning the Achilles tendon and the knee. A validation study from the Danish National Patient Register.
Markus Gadeberg, Allan Cramer, Per Hølmich, Kristoffer Barfod
Sports Orthopedic Research Center (SORC-C), Hvidovre Hospital; Sports Orthopedic Research Center (SORC-C), Hvidovre Hospital; Sports Orthopedic Research Center (SORC-C), Hvidovre Hospital; Sports Orthopedic Research Center (SORC-C), Hvidovre Hospital


Background: The diagnosis codes for sports injuries in the Danish National Patient Register (DNPR) are frequently used for research, however the validity is unknown.
Purpose / Aim of Study: The aim was to investigate the validity of diagnosis codes for some of the most common sports related injuries: acute Achilles tendon rupture (DS86.0A), Achilles tendinitis (DM76.6), rupture of anterior cruciate ligament of the knee (ACL) (DS83.5E), dislocation of the patella (DS83.0), traumatic tear of the meniscus (DS83.2) and degenerative meniscal lesion (DM23.2).
Materials and Methods: The study was performed as a registry study in the DNPR. For each diagnosis code, patient records from Copenhagen University Hospital Hvidovre were retrieved from January 1st to December 31st 2017. We considered a positive predictive value (PPV) of 80% or higher to be satisfying.
Findings / Results: The population consisted of 85 patients registered with the diagnosis code for acute Achilles tendon rupture, 65 patients with Achilles tendinitis, 73 patients with ACL rupture , 100 patients with dislocation of the patella , 100 patients with traumatic tear of the meniscus, and 100 patients with degenerative meniscal lesion. For acute Achilles tendon rupture the PPV was 98% (95% CI: 92%-100%), for Achilles tendinitis 85% (95% CI: 74%-92%), for ACL rupture 96% (95% CI: 88%-99%) and for dislocation of the patella 96% (95% CI: 90%-99%). Depending on the definition of the diagnoses, the PPVs were 56%-72% for traumatic tear of the meniscus and 53%-77% for degenerative meniscal lesion.
Conclusions: This study documented a satisfying validity allowing for epidemiological research concerning the diagnosis codes for acute Achilles tendon rupture, Achilles tendinitis, ACL rupture and dislocation of the patella. The diagnosis codes for traumatic tear of the meniscus and degenerative meniscal lesion showed a lower validity and should therefore be used with caution.

123. Rehabilitation with blood flow restriction resistance exercise in patients with early weight bearing restrictions after knee surgery: A feasibility study
Thomas Linding Jakobsen, Kristian Thorborg, Jakob Fister, Thomas Kallemose, Thomas Bandholm
Section for Orthopaedic and Sports Rehabilitation (SOS-R), Health Centre Nørrebro, City of Copenhagen; Department of Orthopedic Surgery , Amager and Hvidovre Hospital ; Section for Orthopaedic and Sports Rehabilitation (SOS-R), Health Centre Nørrebro, City of Copenhagen; Clinical Research Centre, Amager and Hvidovre Hospital; Department of Orthopedic Surgery, Amager and Hvidovre Hospital


Background: In musculoskeletal rehabilitation, blood flow restriction (BFR) resistance exercise is potentially indicated in patients who may not load tissues as required for “classic” heavy resistance exercise.
Purpose / Aim of Study: The purpose of this study was to explore the feasibility of rehabilitation with BFR resistance exercise in patients with early weight bearing restrictions after knee meniscus or cartilage repair.
Materials and Methods: In total, 42 patients with meniscus (n=21) or cartilage repair (n=21) attended 9 weeks of supervised rehabilitation with BFR resistance exercise at an outpatient rehabilitation center (5 sessions/week). Clinical outcomes were assessed at different time points from 2 to 26 weeks postoperatively and included: Thigh circumference (muscle size proxy), isometric knee-extension strength, knee joint and thigh pain, knee joint range of motion and effusion, perceived exertion, self- reported disability and quality of life, and adverse events.
Findings / Results: On average, patients performed 48 BFR sessions (35 home, 13 supervised). 38 patients reported 64 harms (dizziness, n=52) - none considered serious. Thigh circumference increased 0.6 cm (SD=1.5) from baseline to end of the rehabilitation program for the operated leg from 52.8 to 53.3 cm (p=0.01), and 0.1 cm (SD=1.1) for the healthy leg from 54.9 to 55.0 cm (p=0.41). At 26 weeks postoperatively, isometric knee-extension strength (limb symmetry index) was 83% (SD=25).
Conclusions: Rehabilitation with BFR resistance exercise initiated early after meniscus or cartilage repair seems feasible and may increase thigh muscle mass during a period of weight bearing restrictions. Harms were reported, but no serious adverse events were found. Trial registration: NCT03371901