[Show abstract][Hide abstract] ABSTRACT: The aim of the present study was to evaluate and compare objective and subjective outcome in patients 2 and 5 years after anterior cruciate ligament (ACL) reconstruction with either bone-patellar tendon-bone (BPTB) or hamstring grafts. The second aim was to report the prevalence of re- and contralateral ACL ruptures.
Sixty-eight patients (BPTB, n = 34 and hamstring graft, n = 34) were evaluated preoperatively, 2 and 5 years after ACL reconstruction. Anterior knee laxity and rotational knee joint stability, muscle torque, hop length, anterior knee pain, activity level and self-reported knee function and quality of life were evaluated within and between groups. The prevalence of re- and contralateral ACL ruptures was also recorded.
No significant difference in anterior knee laxity, rotational knee joint stability, hop length anterior knee pain or knee function and quality of life were noted at the 5-year follow-up. No significant differences in concentric or eccentric quadriceps torque at 90°/s and 230°/s were found at any of the follow-ups between and within grafts. A significant group difference in hamstring torque 1.05 (0.02) for BPTB and 0.89 (0.02) for hamstring grafts, and in hop length (leg symmetry index) follow-up 0.94 (0.07) for BPTB compared to 0.99 (0.07) for hamstring grafts (P = 0.002) was found at the 2 year follow-up in favour of the BPTB graft, but not at the 5 year follow-up. A significant improvement over time, irrespective of graft, was found in the KOOS's subscales Sport/Rec and quality of life (P < 0.001). None of the patients, irrespective of group, returned to their pre-injury level of sport (P < 0.05). Over the five postoperative years, one man and eight women (13 %) (hamstring graft, n = 5 and BPTB graft, n = 4), sustained a total of 11 (16.2 %) new ACL ruptures: seven (10.2 %) re-ruptures and four (5.9 %) ruptures of the contralateral ACL.
At the 5-year follow-up, there were no significant differences in terms of anterior knee laxity, rotational knee joint stability, muscle torque, anterior knee pain, hop performance, quality of life or activity level between patients who had undergone reconstruction with BPTB or hamstring grafts. None of the patients, irrespective of group, had returned to their pre-injury level of activity. Eight out of the nine patients who had sustained a second ACL rupture were women. LEVEL OF EVIDENCE: II.
[Show abstract][Hide abstract] ABSTRACT: The aim of this article is to provide a state-of-the-art review for treatment of acute, total proximal hamstring tendon ruptures. For total proximal hamstring tendon ruptures, early (<2-3 w) surgical refixation minimizes muscle atrophy and facilitates a somewhat predictable time course for healing and rehabilitation. A postoperative rehabilitation program is detailed that has been used by one physical therapist for the past 7 years on over 200 patients with surgical repair for total proximal hamstring tendon rupture. One re-rupture has occurred, 7 months after surgery, following the rehabilitation program described herein. The rehabilitation program, including avoidance of postoperative bracing, appears effective for total proximal hamstring ruptures. Early surgery together with a specific rehabilitation program appears to be the treatment of choice for timely and safe return to sport and an active lifestyle. Level of evidence V.
[Show abstract][Hide abstract] ABSTRACT: PURPOSE: The aim of this prospective randomized intervention study was to evaluate the outcome at a 2 and 5 year follow-up whether combined arthroscopic surgery followed by exercise therapy was superior to the same exercise therapy alone when treating non-traumatic, degenerative medial meniscal tears. METHODS: Ninety-six middle-aged patients with MRI-verified degenerative medial meniscus tear and radiographic osteoarthritis grade ≤1 (Ahlbäck) participated in the study. Radiographic examination was done before randomization and after 5 years. The patients were randomly assigned to either arthroscopic treatment followed by exercise therapy for 2 months or to the same exercise therapy alone. At the start of the study and at the follow-ups at 24 and 60 months the patients answered three questionnaires KOOS, Lysholm Knee Scoring Scale and Tegner Activity Scale and made pain ratings on the Visual Analogue Scale (VAS). RESULTS: Both groups showed highly significant clinical improvements from baseline to the follow-ups at 24 and 60 months on all subscales of KOOS, Lysholm Knee Scoring Scale and VAS (p < 0.0001). No group differences were found at any of the testing occasions. One third of the patients that were treated with exercise therapy alone did not feel better after the treatment but were improved after arthroscopic surgery. According to radiographic findings two patients from each group had a slight progression of their osteoarthritis after 5 years. CONCLUSION: The findings indicate that arthroscopic surgery followed by exercise therapy was not superior to the same exercise therapy alone for this type of patients. Consequently, exercise therapy can be recommended as initial treatment. However, one third of the patients from the exercise group still had disabling knee symptoms after exercise therapy but improved to the same level as the rest of the patients after arthroscopic surgery with partial meniscectomy. LEVEL OF EVIDENCE: I.
[Show abstract][Hide abstract] ABSTRACT: The aim was to investigate injury risk factors in junior tennis players. Fifty-five players, 35 boys and 20 girls, answered a questionnaire about training habits, time of exposure, previous injuries and equipment factors. A battery of clinical tests and functional performance tests were also carried out. All tennis-related injuries that occurred during a 2-year period were identified and recorded. An injury was defined as an injury if it was impossible to participate in regular tennis training or playing matches during at least one occasion, a time loss injury. Potential injury risk factors were tested in a forward stepwise logistic regression model for injury. Thirty-nine players sustained totally 100 new and recurrent injuries. Injuries to the lower extremity were the most common ones (51%) followed by the upper extremity (24%) and the trunk (24%). Injured players performed more singles per week (P<0.0001) and played more tennis hours per year (P=0.016) than the uninjured players. Playing tennis more than 6 h/week was found to be a risk factor for back pain. A previous injury regardless of location was identified as an injury risk factor, and a previous injury to the back was a risk factor for back pain.
Scandinavian Journal of Medicine and Science in Sports 02/2012; 22(1):40-8. DOI:10.1111/j.1600-0838.2010.01129.x · 2.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The purpose of this article is to present recommendations for new muscle strength and hop performance criteria prior to a return to sports after anterior cruciate ligament (ACL) reconstruction.
A search was made of relevant literature relating to muscle function, self-reported questionnaires on symptoms, function and knee-related quality of life, as well as the rate of re-injury, the rate of return to sports and the development of osteoarthritis after ACL reconstruction. The literature was reviewed and discussed by the European Board of Sports Rehabilitation in order to reach consensus on criteria for muscle strength and hop performance prior to a return to sports.
The majority of athletes that sustain an (ACL) injury do not successfully return to their pre-injury sport, even though most athletes achieve what is considered to be acceptable muscle function. On self-reported questionnaires, the athletes report high ratings for fear of re-injury, low ratings for their knee function during sports and low ratings for their knee-related quality of life.
The conclusion is that the muscle function tests that are commonly used are not demanding enough or not sensitive enough to identify differences between injured and non-injured sides. Recommendations for new criteria are given for the sports medicine community to consider, before allowing an athlete to return to sports after an ACL reconstruction.
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to prospectively make a survey of injuries in junior players from a Swedish local tennis club during a 2-year period in relation to gender, anatomic location, month of the year when injured, injury type and injury severity. All 12-18 years old members in a tennis club playing more than twice weekly were asked to participate. Fifty-five junior tennis players, 35 boys and 20 girls accepted to participate. All tennis-related injuries were prospectively registered and evaluated. Time of exposure for playing tennis was recorded. Thirty-nine players sustained 100 injuries, 73 in boys and 27 in girls. Injury incidence for boys was 1.7 injuries/1000 h of tennis playing time and for girls 0.6 injuries/1000 h. Ankle sprains, low back pain and knee injuries were the most common ones. Sixty-five percent were new injuries, and the majority of these injuries were located at the knee joint followed by the ankle joint, while most of the recurrent injuries were found in the lumbar spine. Boys suffered mainly from low back pain and ankle injuries and girls from low back pain and knee injuries. Forty-three percent of the injuries caused absence from tennis for more than 4 weeks and 31% more than 1 week.
[Show abstract][Hide abstract] ABSTRACT: Sixty-eight patients were clinically evaluated preoperatively, 3, 5, 7, 9 months, 1 and 2 years after ACL reconstruction, 34 with patellar tendon graft, 34 with hamstring graft. Outcome regarding graft choice and anterior knee laxity (P = 0.04) was in favour of patellar tendon graft. Hamstring graft led to a larger laxity, 2.4 mm compared with patellar tendon graft, 1.3 mm at 1 year and 2.5 mm and 1.5 mm, respectively, at 2 years (P = 0.05). There was a significant difference in rotational knee stability in favour of the patellar tendon graft at all test occasions but 9 months. A general effect regarding graft choice and muscle torque was found at 90 degrees/s for quadriceps (P = 0.03) and hamstrings (P < or = 0.0001) and at 230 degrees/s for hamstrings (P < or = 0.0001). No treatment effect regarding graft choice and one-leg hop test, postural sway or knee function was found. No group differences in anterior knee pain were found at any of the test occasions but 2 years in favour of hamstring graft compared to patellar tendon graft (P = 0.04). Patellar tendon graft resulted in higher activity level than hamstring graft at all test occasions but 1 year (P = 0.01). Patellar tendon ACL reconstruction led to more stable knees with less anterior knee laxity and less rotational instability than hamstring ACL reconstruction. Hamstring graft patients had not reached preoperative level in hamstring torque even 2 years after ACL reconstruction. Athletes with patellar tendon graft returned to sports earlier and at a higher level than those with hamstring graft.
[Show abstract][Hide abstract] ABSTRACT: The aim of the present investigation was to study patient-reported long-term outcome after anterior cruciate ligament (ACL) reconstruction. On an average 11.5 years after ACL reconstruction with bone-patellar tendon-bone (BPTB) autograft 56 patients were asked to answer four different questionnaires about their knee function and knee-related quality of life. Another aim was to study whether there were any correlations between clinical tests, commonly used for evaluating patients with ACL injuries, which were performed 2 years after ACL reconstruction, and patient-reported outcome in terms of knee function and knee-related quality of life on an average 9.5 years later. All patients who had unilateral BPTB ACL reconstructions were examined at 2 years and on an average 11.5 years after surgery. At 2 years one-leg hop test for distance, isokinetic muscle torque measurement, sagittal knee laxity, Lysholm knee scoring scale and Tegner activity scale were used for clinical evaluation. At the follow-up on an average 9.5 years later the patients were evaluated with knee injury osteoarthritis outcome score (KOOS), short form health survey (SF 36), Lysholm knee scoring scale and Tegner activity scale. The SF-36 showed that the patients had a similar health condition as an age- and gender-matched normal population in Sweden on an average 11.5 years after ACL reconstruction. There was no correlation between the results of one-leg hop test for distance, isokinetic muscle torque measurement, sagittal knee laxity evaluated 2 years after surgery and the result of KOOS (function in sport and recreation, knee-related quality of life) and SF-36 evaluated on an average 11.5 years after surgery. We also compared patients that 2 years after surgery demonstrated a side-to-side difference in anterior-posterior knee laxity of more than 3 mm with those with 3 mm or less and found no significant group differences in terms of knee function as determined with KOOS. We found no correlation between the results of KOOS and SF-36 at the long-term follow-up and the time between injury and surgery, age at surgery or gender, respectively. We conclude that there is no correlation between patient-reported knee function in sport and recreation and knee-related quality of life on an average 11.5 years after BPTP ACL reconstruction and the evaluation methods used 2 years after surgery.
[Show abstract][Hide abstract] ABSTRACT: There is a lack of knowledge regarding predictive factors for a successful clinical outcome after an anterior cruciate ligament (ACL) reconstruction. The aim was to investigate pre-operative factors that may predict good outcomes as measured with the subscales Function in sports and recreation and Quality of life in Knee injury Osteoarthrithis Outcome Score (QOL-KOOS), one-leg hop test and Tegner Activity Scale 12 months after ACL reconstruction. Sixty-four patients, operated with either patellar or hamstring tendon graft, were included. Demographics, range of motion, anterior knee laxity, pivot shift, muscle-torques, anterior knee pain (AKP) and knee function were registered pre-operatively and used in a multiple regression model. Results show less degree of AKP and low influence on knee function to be the most important predictors for good outcome in Sport/Rec-KOOS (explained 31% of variances). Less AKP was in addition the most important predictor for QOL-KOOS (14%). Patellar-tendon graft, in favor of hamstring tendon graft, explained 8% of the improvement in the Tegner Activity Scale. In conclusion, a low degree of AKP was found to be the most important predictor for good clinical outcome 12 months after ACL reconstruction. Future studies, including psychological parameters, should use analyses that have the potential to control for independency between variables.
Scandinavian Journal of Medicine and Science in Sports 09/2008; 19(6):842-9. DOI:10.1111/j.1600-0838.2008.00852.x · 2.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Gymnasts are known to practice and compete although suffering from injuries and pain. Pain may change strategies for postural control. The primary aim of the present study was to investigate how center of pressure (COP) measurements are influenced by low back pain and lower extremity injury in top-level female gymnasts. A secondary aim was to study the reliability of these measurements using a test-retest design, and how this depends on the duration of the test. Fifty-seven top-level gymnasts were included in four groups: non-injured (NI, n=18), low back pain (LBP, n=11), lower extremity injury (LEI, n=17) and a multiple injury group (MI, n=11). COP excursion during quiet stance was measured on a force platform, during 120s: (1) hard surface/eyes open, (2) hard surface/eyes closed, (3) foam surface/eyes open and (4) foam surface/eyes closed. The COP excursion increased, for all groups, during the foam surface/eyes closed measurement compared to the other three tests. Furthermore, the LBP group showed a 49% (p=0.01) larger COP area compared to the LEI group in the foam surface/eyes closed condition. Measurements on foam surface were in general more reliable than tests on hard surface and tests with eyes closed were more reliable than tests with eyes open. Tests during 120s were in most cases more reliable than tests during 60s. In conclusion the COP excursion is influenced by injury location. Quiet stance measurements on foam surface with eyes closed seems to be reliable and sensitive in young female gymnasts.
[Show abstract][Hide abstract] ABSTRACT: The aim was to explore patients' experiences of the rehabilitation process after anterior cruciate ligament (ACL) reconstruction. Ten participants were enrolled in the study. Semi-structured interviews were performed, focusing on challenges during the post-operative rehabilitation to 1 year after ACL reconstruction. The participants perceived no real choice between operative and non-operative treatment. Only surgery symbolized a full return to the pre-injury level of sports, and surgery was understood as the only way to become a completely restored "functional human being." A major source of frustration was that the meaning of and progress during the rehabilitation did not match their expectations. Three different responses to the challenge of a prolonged rehabilitation were expressed: "going for it,"being ambivalent," and "giving in." Fear of re-injury was common; however, some participants decided not to return to their pre-injury level of sports due to reasons other than physical limitations or fear of re-injury. From a patient perspective, it seems important that the choice of operative or non-operative treatment should be discussed in terms of the meaning and extent of the post-operative rehabilitation and the expected outcomes. There also seems to be a need for more guidance in realistic goal setting and coaching throughout the rehabilitation process.
Scandinavian Journal of Medicine and Science in Sports 07/2008; 18(3):325-35. DOI:10.1111/j.1600-0838.2007.00700.x · 2.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The incidence of anterior cruciate ligament (ACL) injury remains high in young athletes. Because female athletes have a much higher incidence of ACL injuries in sports such as basketball and team handball than male athletes, the IOC Medical Commission invited a multidisciplinary group of ACL expert clinicians and scientists to (1) review current evidence including data from the new Scandinavian ACL registries; (2) critically evaluate high-quality studies of injury mechanics; (3) consider the key elements of successful prevention programmes; (4) summarise clinical management including surgery and conservative management; and (5) identify areas for further research. Risk factors for female athletes suffering ACL injury include: (1) being in the preovulatory phase of the menstrual cycle compared with the postovulatory phase; (2) having decreased intercondylar notch width on plain radiography; and (3) developing increased knee abduction moment (a valgus intersegmental torque) during impact on landing. Well-designed injury prevention programmes reduce the risk of ACL for athletes, particularly women. These programmes attempt to alter dynamic loading of the tibiofemoral joint through neuromuscular and proprioceptive training. They emphasise proper landing and cutting techniques. This includes landing softly on the forefoot and rolling back to the rearfoot, engaging knee and hip flexion and, where possible, landing on two feet. Players are trained to avoid excessive dynamic valgus of the knee and to focus on the "knee over toe position" when cutting.
British Journal of Sports Medicine 07/2008; 42(6):394-412. DOI:10.1136/bjsm.2008.048934 · 5.03 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Prospective controlled intervention study. To evaluate a specific segmental muscle training program of the lumbar spine in order to prevent and reduce low back pain in young female teamgym gymnasts. Teamgym is a team sport comprising three events: trampette, tumbling and floor programme. In a recent study, it was found that teamgym gymnasts practice and compete despite suffering from back pain. Specific muscle control exercises of the lumbar spine have shown good results in reducing pain intensity and functional disability levels in patients with low back pain. To our knowledge, this type of training has not been studied in an adolescent athletic population before. Fifty-one gymnasts, with and without LBP, 11-16 years old, from three top-level gymnastics team participated in the study comprising 12 weeks. Every day the gymnasts answered a questionnaire regarding low back pain. After baseline (4 weeks) the intervention group performed a specific segmental muscle training program. Twenty-four gymnasts (47%) reported low back pain during baseline. Nine gymnasts failed to answer the questionnaire every day and the following results are based on 42 gymnasts (intervention group, n = 30, and control group, n=12). Gymnasts in the intervention group reported significantly less number of days with low back pain at completion compared to baseline (P=0.02). Gymnasts in the control group showed no difference in terms of days with low back pain or intensity of low back pain between baseline and completion. Eight gymnasts (out of 15) with LBP in the intervention group became pain free. Specific segmental muscle control exercises of the lumbar spine may be of value in preventing and reducing low back pain in young teamgym gymnasts.
[Show abstract][Hide abstract] ABSTRACT: Many terms have been used to describe what has been called idiopathic adhesive capsulitis of the shoulder. This pathology is defined as a self-limiting condition of unknown etiology. The natural history is 18-30 months even though a high-percentage of patient present impaired range of movement even at long-term follow-up. The diagnosis is mainly clinical and no significant changes are normally present at MRI or CT scan. Several treatment options have been tried over the years with different approaches and results.
[Show abstract][Hide abstract] ABSTRACT: The purpose of the present investigation was to evaluate physical outcome after anterior cruciate ligament (ACL) reconstruction with early versus late initiation of open kinetic chain (OKC) exercises for the quadriceps in patients operated on either patellar tendon or hamstring grafts. Sixty-eight patients, 36 males and 32 females, with either patellar tendon graft (34 patients) or hamstring graft (34 patients) were enrolled in this study. All patients were randomly allocated to either early (the 4th postoperative week) or late (the 12th postoperative week) start of OKC exercises for the quadriceps, resulting in four subgroups: patellar tendon reconstruction, early start (P4) or late start (P12) of OKC quadriceps exercises, hamstring tendon reconstruction, early start (H4) or late start (H12) of quadriceps OKC exercises. Prior to surgery and 3, 5 and 7 months later, assessments of range of motion (goniometer), anterior knee laxity (KT-1000), postural sway (KAT 2000), thigh muscle torques (Kin–Com dynamometer) and anterior knee pain (anterior knee pain score) were evaluated. No significant group differences were found in terms of range of motion 3, 5 and 7 months postoperatively. The H4 group showed a significantly higher mean difference of laxity over time of 1.0 mm (CI: 0.18–1.86) than the P4 group (P = 0.04). Within the same type of surgery, the H4 against the H12, the mean difference over time was 1.2 mm (0.37–2.1) higher in the H4 group than in the H12 group (P = 0.01). There were no significant group differences in terms of postural sway or anterior knee pain at the different test occasions. Significant differences in trends (changes over time) were found when comparing the four groups, for both quadriceps muscle torques (P P
[Show abstract][Hide abstract] ABSTRACT: In this prospective randomised study two treatments after non-traumatic medial meniscal tear diagnosed with radiological examination and magnetic resonance imaging were compared; arthroscopic partial meniscectomy followed by supervised exercise or supervised exercise alone. The aim was to evaluate knee function and physical activity. Ninety patients (mean age 56 years) were evaluated using the Knee Injury and Osteoarthritis Outcome Score, the Lysholm Knee Scoring Scale, the Tegner Activity Scale and a Visual Analogue Scale for knee pain prior to the intervention, after 8 weeks of exercise and after 6 months. According to the outcome scores arthroscopic partial medial meniscectomy combined with exercise did not lead to greater improvement than exercise alone. After the intervention both groups reported decreased knee pain, improved knee function and a high satisfaction (P<0.0001). Forty-one per cent of the patients returned to their pre-injury activity level after 6 months. In conclusion, when evaluated with outcome scores, arthroscopic partial medial meniscectomy followed by supervised exercise was not superior to supervised exercise alone in terms of reduced knee pain, improved knee function and improved quality of life.
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to evaluate injury incidence, mechanism and diagnosis in Swedish teamgym. Sixteen male and 26 female gymnasts with international experience were prospectively followed during one season of training and competition. Injuries leading to a modified participation or total absence from gymnastics during 1 week or more were registered. Twenty-seven of the 42 gymnasts sustained 42 injuries. The injury incidence was 2.2/1000 gymnastics hours. No gender differences were found. Sixty-two percent of the injuries were located to the lower extremity, 28.5% to the back and 9.5% to the upper extremity. The most common injury was ankle sprain and the most frequent mechanisms were joint compression and joint rotation. The majority of the injuries occurred in the landing phase of the gymnastics skills and 50% of the injuries were reported at the end of the training session. Eighteen injuries occurred while the gymnasts were in a negative state of mood such as stressed or afraid. Injury prevention programs should be developed with respect to these findings. Special emphasis must be placed on the landing phase of the gymnastics skills as this phase seems to be critical.
Scandinavian Journal of Medicine and Science in Sports 04/2007; 17(2):115-9. DOI:10.1111/j.1600-0838.2006.00546.x · 2.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The aim of the present investigation was to compare the costs for the use of patellar tendon versus hamstring tendons as grafts for anterior cruciate ligament (ACL) reconstruction including the different fixation methods. The background is that during recent years there has been a dramatic shift from patellar tendon to hamstring tendons in ACL reconstructions in Sweden. All our patients with ACL reconstructions performed during 1 year (2004) were included. Knee joints numbering 440 in 439 patients were primary ACL reconstructions. A hamstring graft was used in 345 knee joints (78.4%) and a patellar tendon graft in 95 (21.6%) of the patients (Table 2). On average 34 (SD 12.9; range 14-63) ACL reconstructions per surgeon were performed by a total of 14 surgeons. The average cost for patellar tendon procedure was 197 euros compared to 436 euros for the hamstring procedure. Mean time for surgery in primary reconstructions was 11.5 min shorter (P<0.001) for patellar tendon reconstructions (71.3+/-31 min) compared to hamstring reconstructions (83.2+/-27 min). This means a difference in cost of 90 euros. The total additional cost (fixation and surgery time) for the hamstring method compared to the patellar tendon method was on an average 329 euros. From a strict economic point of view we therefore recommend or at least consider the use of the patellar tendon as a graft in ACL reconstructions.
[Show abstract][Hide abstract] ABSTRACT: The aim of the study was to evaluate differences between competitive swimmers and a reference group of school children concerning general joint laxity, laxity of the glenohumeral joint and range of motion in the shoulder. Materials and methods. Competitive swimmers (n=120) were compared with references consisting of age and gender matched school children (n=1277). General joint laxity was evaluated with the Beighton score. Anterior glenohumeral laxity was assessed according to the drawer test, and inferior glenohumeral laxity according to the sulcus test. Shoulder rotation was measured with a goniometer.
Results. Male swimmers of both age groups showed a higher degree of general joint laxity compared with the reference group while 9-year-old female swimmers alone had a lower degree of general joint laxity compared with references. No significant difference concerning shoulder laxity was noticed between groups. There was a decreased internal rotation in male and female swimmers as compared with the reference group. External rotation was reduced in female swimmers as compared with the female references. The same result was observed in male swimmers, but only at the age of 12 years.
Clinical consequence: Competitive swimming in children seems to lead to a decreased range of motion with regard to shoulder rotation. However, the reason for this is still unclear and further investigations are needed.
Scandinavian Journal of Medicine and Science in Sports 07/2005; 15(3):169-76. DOI:10.1111/j.1600-0838.2004.00417.x · 2.90 Impact Factor