Session 2: Sportstrauma

Ondag den 22. oktober
09:00 – 10:30
Lokale: Stockholm/Copenhagen
Chairmen: Morten Boesen Morten / Michael Rindom Krogsgaard

13. Is the use of oral contraceptives associated with operatively treated anterior cruciate ligament injury? A case-control study from the Danish Registry of Knee Ligament Reconstruction
Lene Rahr-Wagner, Theis Thillemann, Frank Menhert, Alma Pedersen, Martin Lind
department of ortopaedic surgery, Aalborg University Hospital; department of clinical epidemiology, Aarhus University Hospital; department of ortopaedic surgery, sports medicine, Aarhus University Hospital

Background: The incidence of anterior cruciate ligament (ACL) injuries is 2-9 times higher in women than in men. Additionally, in vitro studies have demonstrated that ACL is an estrogen target tissue, and some studies have therefore suggested a protective association between oral contraceptives (OC) and the likelihood of sustaining ACL injury.
Purpose / Aim of Study: The aim was to test the hypothesis of a protective association between OC use and the likelihood of sustaining operatively treated ACL injury.
Materials and Methods: The study population included 4,497 female cases with an operatively treated ACL injury registered in the Danish Registry of Knee Ligament Reconstruction for the 2005-2011 period and 8,858 age-matched controls with no ACL injury. The study evaluated exposure to OC use at the time of ACL injury and in the five previous years (ever user) or no OC use (never user). Ever users were further classified as either new users, long-term users or recent users. Finally, a dose-response analysis of OC use was performed. We used conditional logistic regression to calculate the relative risk (RR) with a 95% confidence interval (CI) of sustaining operatively treated ACL injury according to OC use.
Findings / Results: The adjusted RR associating OC with ACL injury was 0.82 (95% CI: 0.75 to 0.90) between ever users and never users. Furthermore, we found a decreased relative risk (RR) of sustaining ACL injury of 0.80 (95% CI: 0.74 to 0.91) in long-term users and 0.81 (95% CI: 0.72 to 0.89) in recent users. Additionally, we found a trend towards a dose-response association. Using OC for more than four years did not seem to alter the likelihood of sustaining operatively treated ACL injury.
Conclusions: This indicates a protective association between OC use and the likelihood of sustaining operatively treated ACL injury.

14. Limited Osteochondral Repair by a Biomimetic Collagen Scaffold - One to Three Years Clinical and Radiological Follow-Up
Bjørn Christensen, Casper Foldager, Niels Christian Jensen, Cody Bünger, Martin Lind
Orthopedic Research Laboratory, Aarhus University Hospital; Department of Orthopedic Surgery, Aarhus University Hospital; Division of Sports trauma, Aarhus University Hospital

Background: Osteochondral injuries are therapeutically challenging and no gold standard treatment has been established. Cell-free, layered scaffolds are a new treatment option for these defects.
Purpose / Aim of Study: The aim of this study was to evaluate the osteochondral repair in patients treated with The MaioRegen® scaffold, a cell-free biomimetic scaffold. It has previously been shown to induce clinical subchondral bone and articular cartilage regeneration.
Materials and Methods: Eleven patients with osteochondral defects in the knee (n=7) or in the talus (n=4) were enrolled. Patients filled out clinical evaluation questionnaires pre-OP and at the final follow-up (2,5 years, range 1,9-3,1 years). The patients underwent pre-OP MRI, and CT and MRI 1 (range 1-1,2 years) and 2,5 years post-OP (range 1,9-3,1 years). The knee patients were evaluated using KOOS, IKDC and Tegner, the ankle patients using AOFAS Hindfoot and Tegners score. The cartilage and bone formation was evaluated using the MOCART score.
Findings / Results: Three patients were re-operated and excluded due to treatment failure. CT: None of the patients had complete regeneration of the bone. 6/8 patients had no or very limited (<10%) bone formation. 1/8 had 20-30% bone filling and 1/8 had 40-50% bone filling. MRI: No improvement was found in the MOCART score at any time point. 5/6 patients experienced a clinical improvement, and one patient a worsening. The results were insignificant.
Conclusions: Treatment of osteochondral defects with the MaioRegen scaffold resulted in incomplete cartilage- and limited subchondral bone repair at 1 and 2,5 year’s follow-up. Three patients were excluded due to treatment failure. This study raises concerns about the biological repair potential of the MaioRegen® implant. Long-term studies are needed to investigate if the clinical improvements are permanent.

15. One-year follow-up after ACL reconstruction – surgeon or physical therapist ?
Ina Wieland Nielsen, Kirsten Bettina Jensen, Jonathan Jetsmark Bjerre, Peder Klement Jensen, Michael R. Krogsgaard
Ergo- and Physical Therapy, Bispebjerg Hospital; Section for Sportstraumatology M51, Bispebjerg Hospital; Dept. of Orthopadic Surgery, Bispebjerg Hospital

Background: One year follow-up after ACL reconstruction is traditionally done by orthopaedic surgeons, often the person who operated, which could lead to bias in the results. One year is also time for return to sports, and patients often request instruction for further rehabilitation.
Purpose / Aim of Study: To replace surgeons with physical therapists (PTs) at one-year follow-up and evaluate if stability measures changed.
Materials and Methods: Between 1.5.13 and 30.4.14 (P2) one- year follow-up of patients after ACL reconstruction were done by one of two specially trained PTs and only by a surgeon if problems were reported. Stability measures including Lachman-, drawer- and pivot-tests and anterior laxity with Rolimeter in both knees were performed. In addition 4 functional tests were done. The same stability measurements were performed by the surgeons in a previous period: 1.5.12 – 30.4.13 (P1), and results for the two periods were compared.
Findings / Results: Rolimeter measures right/left were 5,63/5,79 mm in P1 and 6,96/7,07 mm in P2. Measures were significantly higher for both knees in P2 (t-test: p < 0,001). The difference between operated and non-operated knee in P1/P2 was 1,38/1,98 mm (p = 0,008). There were more positive drawer tests (p = 0,005) during P1, but no difference for Lachman and pivot-tests (p > 0,05). Standard rehabilitation plans (GOPs) had been sent to the local therapists following reconstruction, but the content of the actual rehabilitation varied and many patients asked for further instruction.
Conclusions: Absolute measures and differences in Rolimeter measurements were higher during the period when PTs tested, indicating that PTs and surgeons might test differently. An advantage of PT follow-up is the possibility for further instructions, functional testing results and release of surgeons’ time.

16. The association between patient-reported outcomes and physical outcome measures in Danish patients one year after anterior cruciate ligament reconstruction
Jonathan Comins, Bettina Jensen, Ina Wieland Nielsen, Volkert Siersma, Michael Krogsgaard
Section for Sports Traumatology M51, Bispebjerg Hospital; 3Department of Occupational and Physical Therapy, Bispebjerg Hospital; Research Unit and Section of General Practice, Department of Public Health, University of Copenhagen

Background: Patient-reported outcome measures (PROMs) fail to correlate with anterior laxity and functional performance tests in patients with anterior cruciate ligament (ACL) deficiency. A recent Korean study found that the IKDC PROM correlates significantly with laxity and functional performance in patients with ACL reconstruction.
Purpose / Aim of Study: We assessed the degree of association between two different PROMs (KNEES-ACL and IKDC) and anterior laxity and standard functional performance tests in Danish patients one year post ACL reconstruction.
Materials and Methods: Eighty-six patients who had undergone ACL reconstruction one year previously were retrospectively included. Patients completed KNEES-ACL and IKDC and a physical therapist applied tests of knee ligament laxity and a battery of standardized functional performance tests. Between-knee differences were computed and Spearmans rho correlations were assessed between the seven subscales of KNEES, the IKDC total score, between-knee laxity values, and functional performance tests.
Findings / Results: All KNEES subscores correlated highly significantly with the IKDC total score. KNEES ADL, Symptoms, and Slackness correlated highest with IKDC at between 0.67 and 0.78. Correlations between the other KNEES subscales and IKDC ranged from 0.36 to 0.57. There were low associations between laxity and functional performance. All KNEES subscales correlated highly significantly with one another.
Conclusions: The IKDC and the KNEES-ACL do not correlate highly with physical outcome measures in Danish patients one year post ACL reconstruction. The IKDC correlates best with the constructs of ADL, Symptoms, and sensation of instability (Slackness) in the KNEES-ACL. This supports the notion that both PROMs and physical measures are necessary to assess surgical outcome in patients treated for ACL deficiency.

Mikkel Bek Clausen, Lars Tang, Mette Kreutzfeldt Zebis, Peter Krustrup, Per Hölmich, Kristian Thorborg
School of Physiotherapy, Institute of Rehabilitation and Nutrition, Faculty of Health and Technology, Metropolitan University; Arthroscopic Centre Amager, SORC-C, Copenhagen University Hospital, Amager-Hvidovre, Denmark; Gait Analysis Laboratory, Copenhagen University Hospital, Hvidovre, Denmark; Department of Nutrition, Exercise and Sports (NEXS), Section of Human Physiology, Copenhagen Centre for Team Sport and Health, University of Copenhagen, Copenhagen, Denmark

Background: Knee-injuries are common in adolescent female football. Severe knee-injuries can cause persistent symptoms, potentially forcing female players to retire from contact sport. Previous knee-injury is recognized as a risk factor for future knee-injuries in adult football, but evidence regarding adolescent female football is scarce and contains important methodological flaws.
Purpose / Aim of Study: The primary aim of this study was to investigate the risk of sustaining future knee-injury in relation to previous knee-injuries. Secondly, low Knee Osteaoarthritis Outcome Score (KOOS) was investigated as a potential risk factor for future knee injuries.
Materials and Methods: A population based sample of 326 girls (15-18 years) without knee-injury at baseline, participating in a Danish Football Association series during the spring 2012 season, was included. Self-reported data on previous knee-injury and KOOS- score were collected at baseline. Football-injuries and football-exposures were reported weekly by answers to standardised text-message questions followed by individual injury-interviews. A priori, previous knee-injury and low KOOS-scores (< 80 points) were chosen as independent variables of interest in the primary and secondary risk-factor analyses.
Findings / Results: 29 players sustained 34 time-loss knee-injuries. Adjusted for match/total ratio and playing-level, baseline report of previous knee-injury significantly increased the risk of time-loss knee-injury (RR: 3.65 95%CI 1.73-7.68; p<0.001). Low baseline-score in three KOOS sub-scales (ADL, Sport/rec and QOL) significantly increased the risk of time-loss knee-injury (RR: 2-5, p= 0.008-0.046).
Conclusions: Previous knee-injury and KOOS subscale scores lower than 80 points in ADL, Sport/rec and QOL significantly increases the risk of sustaining a knee-injury in adolescent female football players.

18. Significant role on rotatory stability of the anterolateral ligament in ACL insufficient knees
Mette Tavlo, Salameh Eljaja, Jørgen Tranum-Jensen, Volkert Siersma, Michael Rindom Krogsgaard
Institut for Cellulær og Molekylær Medicin, Københavns Universitet; Afdeling for Idrætskirurgi, Bispebjerg Hospital; Forskningsenheden for Almen Praksis, Center for Sundhed og Samfund

Background: Recent studies have described the anatomy of an anterolateral ligament (ALL) of the knee. This ligament has been linked to the Segond fracture that is patognomonic for tear of the anterior cruciate ligament (ACL). ALL is hypothesised to be important for the internal rotatory stability of the knee, but its mechanical effect has yet to be clarified.
Purpose / Aim of Study: Our aim was to test the function of the ALL for rotatory and anterior-posterior (AP) stability in ACL insufficient and reconstructed knees and the effect of anatomical ALL reconstruction with a tendon.
Materials and Methods: In 18 cadaver legs ALL was dissected. Function of ALL (+/- ALL) and of ALL reconstruction (reALL) was tested with the ACL removed (-ACL) and reconstructed (+ACL) with following combinations: +ACL-ALL, +ACL+ALL, - ACL+ALL, -ACL-ALL, -ACL+reALL and +ACL+re-ALL. All combinations were tested with the knees in 0, 30, 60 and 90 degrees of flexion. AP stability was tested with a Rolimeter. Rotation of tibia was applied with 50 N internal and external and measured photographically from K-wires inserted in tibia and femur.
Findings / Results: The ALL did not appear uniform, but was well defined in 78 %. ACL (+/-) had a significant effect on the AP stability but not on rotation. ALL (+/-) had significant effect on the rotatory stability (p = 0.0006), regardless of the condition of ACL, and on the AP stability in ACL insufficient knees (p = 0.023). The lost stability of ALL was regained when ALL was reconstructed.
Conclusions: ALL is a major rotational stabilizer. If ALL is torn in connection with ACL rupture, reconstruction of ACL is not re-establishing rotatory stability. When ALL is reconstructed anatomically, rotatory instability is re- established. ALL reconstruction as supplement to ACL reconstruction might be considered in patients with a Segond fracture.

19. Redislocation after conservative treatment of primary patellar dislocations
Bo Kaewkongnok, Anders Bøvling, Celia Møllenborg, Bjarke Viberg, Lars Blønd
Orthopaedic Surgery , Køge; Orthopaedic Surgery and Traumatology , Odense University Hospital; Orthopaedic Surgery, Køge

Background: Primary patellar dislocation should be treated conservatively using either a immobilizing brace or a plaster splint, except for cases with osteochondral fracture. No studies have yet focused on various treatment regimens in relation to the duration of immobilization.
Purpose / Aim of Study: This study compares different conservative treatment regimes after primary patella dislocation measuring the rate of redislocation.
Materials and Methods: Retrospective study comparing two cohorts from two hospitals, having two different conservative treatment protocols. The first regime consist of 2 weeks 30 degree locked brace and the second regime consist of 6 weeks brace with gradually increasing range of movements after two weeks. Patients under 30 years having first-time patellar dislocations were included. Redislocations, treatment regimens, type of rehabilitation and trochlea dysplasia and patella alta on radiographs were recorded.
Findings / Results: 458 patients having 475 primary patella dislocations (230 females) with a median age of 17.0 years (IQR 14.9-20.5) were included. Re-dislocations (or surgery) were recorded for 132 patients with a median re-dislocation time of 347 days (IQR 170-704). X-ray images suited for measurement showed a dysplasia proportion of 72.9%. A logistic regression analysis showed that increasing age (OR 0.82, p<0.0001), instruction in VMO exercises (OR 0.31, p<0.048), and increasing Insall-Salvati index (OR 0.047,p<0.009) all were preventive of re-dislocations. None of the treatment regimes showed any statistical significant difference for preventing re-dislocations.
Conclusions: We found no difference between the two conservative treatment protocols in respect to the rate of re-dislocation. Increasing age, instructions in VMO exercises and increasing Insall-Salvati index was found to be preventive for re-dislocation.

20. Do ACL patients suffer from comorbidity and is there any association between comorbidity and the risk of ACL revision surgery? A nationwide population-based case-cohort study of 13,443 ACL reconstructed patients
Lene Rahr-Wagner, Theis Thillemann, Martin Lind, Alma Pedersen
Department of Orthopaedic surgery, Aalborg University Hospital; Department of Clinical Epidemiology, Aarhus University Hospital

Background: Anterior cruciate ligament (ACL) reconstructed patients are considered healthy individuals. However, information on comorbid disease is lacking.
Purpose / Aim of Study: The aim of this study was to describe and compare comorbid conditions among ACL reconstructed patients and a matched cohort without ACL injury. Further, to evaluate the impact of comorbid diseases on the risk of ACL revision surgery.
Materials and Methods: This case-cohort study included 13,443 unilateral primary ACL reconstructed patients from the Danish Knee Ligament Reconstruction Register (DKRR) matched on gender and age with a comparison cohort without ACL injury. Information on medical comorbid conditions was obtained from the Danish National Registry of Patient. The prevalence of all comorbid conditions was described for ACL reconstructed patients and the comparison cohort in terms of: 1) Charlson Comorbidity Index (CCI) 2) ICD-10 disease chapters, 3) more common chronic diseases in a younger population. Finally we assessed the risk of ACL revision surgery according to the comorbid conditions, using Cox regression analysis.
Findings / Results: ACL reconstructed patients had generally a slightly lower prevalence of almost all ICD-10 classified comorbid disease groups compared to the comparison cohort without ACL injury. The percentage of CCI=0 was high in both groups. As expected most diseases increased slightly with rising age. Most of the comorbid conditions did not affect the risk of revision surgery.
Conclusions: This study provides new information on comorbid conditions in ACL reconstructed patients, which has not previously been described. This study supports the hypothesis that ACL patients are generally healthy individuals. A large variety of diseases are present in the ACL reconstructed group, but with very low prevalence and a low CCI indicating a healthy cohort.

21. Autologous Dual Tissue Transplantation for Osteochondral repair - One Year Clinical and Radiological Follow-Up
Bjørn Christensen, Casper Foldager, Martin Lind
Orthopedic Research Laboratory, Aarhus University Hospital; Division of Sports trauma, Aarhus University Hospital

Background: Articular cartilage has a very limited potential for spontaneous regeneration, due to the avascular nature of the tissue. Numerous treatment methods have been implemented, among them microfracture, ACI and mosaicplasty, but no Gold standard treatment has been established.
Purpose / Aim of Study: To evaluate the use of Autologous Dual- Tissue Transplantation (ADTT): An easily applicable, low cost treatment option for articular cartilage repair.
Materials and Methods: Eight patients (age 33 years, range: 24-45) suffering from osteochondral defects of the medial femoral condyle were enrolled. The injury area was debrided and the osteochondral defect was filled with autologous bone from the tibial tuberosity, to the level of the adjacent cartilage. Cartilage biopsies from the intercondylar notch, was chipped, and the cartilage chips were embedded in fibrin glue in the defect. The stability of the treatment was tested with 40 full range motions, and the incision was closed. The patients were evaluated pre- operatively and one year post-operatively using MRI, CT, and clinical scores (KOOS, IKDC and Tegner)
Findings / Results: A significant improvement was found in the IKDC score (from 40,2 – 67,5, p=0,02), the Tegner score (2,8 – 4,6, p=0,01) and KOOS pain, symptoms, sport/rec and quality of life. The MOCART MRI score improved from 30 to 62,5 (p=0,0003). CT imaging showed very good defect filling, with an uneven bone surface.
Conclusions: Treatment of osteochondral injuries in the knee with ADTT resulted in significant clinical and radiological improvements at one year. Despite the limited number of patients and the short-term follow-up, this study highlights ADTT as a promising treatment option for osteochondral injuries.

22. Posterior cruciate ligament reconstruction in skeletal immature children; a case series of six patients.
Ole Gade Sørensen, Peter Faunø, Svend Erik Christiansen, Martin Lind
Orthopedics, University Hospital of Århus

Background: Rupture of the posterior cruciate ligament (PCL) is a rare knee injury in childen with open growth plates. So far only case studies have been reported in the literature. We present follow-up results of six patients with open physes treated with PCL reconstruction.
Purpose / Aim of Study: To evaluate clinical outcome after PCL reconstruction in six skeletal immature patients.
Materials and Methods: Between August 2006 and October 2010 six skeletal immature patients (one girl and five boys) were treated with PCL reconstruction. In 5 cases hamstring tendons autografts were used. One patient was reconstructed with use of a tibialis anterior tendon allograft. At time of surgery median age was 9 years (range 6 – 14). Median follow-up time after surgery was 50 months (range 41 – 90). Outcome was evaluated by KOOS and Tegner scores, Instrumented knee laxity and radiologic long axis leg length measurements.
Findings / Results: Median KOOS score at follow up regarding symptoms, pain, ADL, Sport, and QOL were 79 (range 43 – 100), 89 (range 41 – 100), 99 (range 66 – 100), 70 (range 5 – 100), and 81 (range 19 – 94) respectively. Median Tegner score was 6 (range 4 – 7). Median side to side difference in laxity using KT1000 was 2 mm (range 1 – 5) at 25 degrees of flexion and 3 mm (range 3 – 6) at 70 degrees of flexion. No side to side difference in knee extension was found. In contrast a median difference of 8 degrees of flexion decrease was found . All but one patient had returned to sports at follow-up. One patient had a leg length discrepancy of 16 mm, the index knee being the longer.
Conclusions: PCL reconstruction resulted in fair to good clinical outcome in skeletal immature children.

23. Testing basic competency in knee arthroscopy using a virtual reality simulator: Exploring reliability and validity
Mads Emil Jacobsen, Morten Jon Andersen, Claus Ol Hansen, Lars Konge
Center of Clinical Education, Copenhagen University Hospital Rigshospitalet, Denmark; Department of Orthopedic Surgery, Copenhagen University Hospital Hvidovre, Denmark; Arthroscopic Center Amager, Copenhagen University Hospital Amager, Denmark

Background: Orthopedic residents are confronted with diagnostic arthroscopies early in their training. Arthroscopy differs from traditional open surgery and many residents feel less prepared for arthroscopic procedures. Virtual reality (VR) training and testing could ensure basic competency before proceeding to supervised operations in patients.
Purpose / Aim of Study: The aim of this study was to create a reliable and valid simulation-based test for diagnostic knee arthroscopy.
Materials and Methods: Twenty-six physicians (13 untrained novices and 13 experienced surgeons) performed a test consisting of five procedures on a VR knee arthroscopy simulator. Performance was evaluated by obtaining predefined metrics from the simulator for each procedure from which z-scores, describing inappropriate behavior, were calculated. Reliability was explored by calculating an Intra-class Correlation Coefficient. Validity was explored by comparing the performances of novices and experienced surgeons using independent samples t-tests. Using the contrasting groups method a pass/fail standard was set and its consequences explored.
Findings / Results: One procedure was excluded from the final test due to lack of validity. Z-scores showed an inter-case reliability of 0.87 between the four procedures in the final test. A total z-score was 38.6 ± 27.3 for the novices and 0.0 ± 9.1 for the experienced surgeons (p < 0.0005). The pass/fail standard was set at a total z-score of 15.5 resulting in two of the novices passing the test and a single experienced surgeon failing.
Conclusions: By combining four procedures on a VR arthroscopy simulator we were able to create a valid and reliable test of basic arthroscopic competency, and establish a credible pass/fail standard. The test could help assess and ensure basic competency of junior surgeons before supervised operations in patients.

24. Treatment of posterior cruciate ligament tear combined with postero-lateral instability in skeletal immature children.
Ole Gade Sørensen, Peter Faunø, Svend Erik Christiansen, Martin Lind
Orthopedics, University hospital of Århus

Background: Tear of the posterior cruciate ligament (PCL) in combination with instability of the postero-lateral corner (PLC) is a very uncommon finding in children with open growth plates. We present follow- up results of three patients with open physes treated with PCL and PLC reconstruction.
Purpose / Aim of Study: To evaluate clinical outcome after combined PCL and PLC reconstruction in three skeletal immature patients.
Materials and Methods: Between July 2004 and December 2010 three skeletal immature patients were treated with combined PCL and PLC reconstruction. Age at time of surgery was 7, 7 and 9 years. At follow-up the three patients were 16, 15 and 13 years respectively. Outcome was evaluated by KOOS and Tegner scores, Instrumented knee laxity and radiologic long axis leg length measurements.
Findings / Results: KOOS scores at follow up for patient# 1, regarding symptoms, pain, ADL, Sport, and QOL were 61, 64, 66, 15 and 38. Patient# 2 scores were 86, 100, 100, 100 and 100, whereas patient#3 scored 96, 94, 100, 95 and 81 respectively. Tegner score was 6, 9 and 6 for the three patients. Laxity measurement was only performed for patient#1 and patient#2 at follow-up. Side to side difference in laxity using KT1000 was 0 and 2 mm at 25 degrees of flexion and 1 and 8 mm at 70 degrees of flexion. Side to side difference in knee flexion was 15, 5 and 5 degrees. No difference in knee extension was found. At follow-up all three patients had returned to sports at a recreational level. Leg length discrepancy was found to be 11, 16 and 5 mm, the index knee being the longer in all three patients.
Conclusions: Combined PCL and PLC reconstruction seems to result in variable clinical outcome in skeletal immature children and our data suggest a risk of growth disorder in these patients.