Explore the vast range of titles available.

Anterior knee pain is one of the most common knee problems in physically active individuals. The reason for anterior knee pain has been suggested to be multifactorial with patella abnormalities or extensor mechanism disorder leading to patellar malalignment during flexion and extension of the knee joint. Some patients complain mostly of non-specific knee pain, while others report patellar instability problems. The patients present with a variety of symptoms and clinical findings, meaning that a thorough clinical examination is the key for optimal treatment. Weakness of the quadriceps muscle, especially during eccentric contractions, is usually present in the majority of anterior knee pain patients. However, irrespective of whether pain or instability is the major problem, hypotrophy and reduced activity of the vastus medialis are often found, which result in an imbalance between vastus medialis and vastus lateralis. This imbalance needs to be corrected before quadriceps exercises are started. The non-operative rehabilitation protocol should be divided into different phases based on the patient’s progress. The goal of the first phase is to reduce pain and swelling, improve the balance between vastus medialis and vastus lateralis, restore normal gait, and decrease loading of the patello-femoral joint. The second phase should include improvement of postural control and coordination of the lower extremity, increase of quadriceps strength and when needed hip muscle strength, and restore good knee function. The patient should be encouraged to return to or to start with a suitable regular physical exercise. Therefore, the third phase should include functional exercises. Towards the end of the treatment, single-leg functional tests and functional knee scores should be used for evaluating clinical outcome. A non-operative treatment of patients with anterior knee pain should be tried for at least 3 months before considering other treatment options.

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.

Purpose 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. Methods 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. Results 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. Conclusion 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. Level of evidence IV.

Purpose 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. Methods 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. Results 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. Conclusions 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.

Purpose The aim was to study possible differences of muscle injuries regarding type, localization and the extent of injury between the dominant and non-dominant leg in elite male football players. Another aim was to study the injury incidence of muscle injuries of the lower extremity during match and training. Methods Data were consecutively collected between 2007 and 2013 in a prospective cohort study based on 54 football players from one team of the Swedish first league. The injury incidence was calculated for both match and training, injuries to the hip adductors, quadriceps, hamstrings and triceps surae were diagnosed and evaluated with ultrasonography, and their length, depth and width were measured to determine the extent of structural muscle injuries. Results Fifty-four players suffered totally 105 of the studied muscle injuries. Out of these 105 injuries, the dominant leg was affected in 53 % ( n  = 56) of the cases. A significantly greater extent of the injury was found in the dominant leg when compared with the non-dominant leg with regard to structural injuries of the hamstrings. No other significant differences were found. Conclusions Structural hamstring muscle injuries were found to be of greater extent in the dominant leg when compared with the non-dominant leg. This new finding should be taken into consideration when allowing the football player to return to play after leg muscle injuries. Level of evidence IV.

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.

In this article, I identify three explanations for postwar instability and the failure of peace settlements and test hypotheses derived from each perspective. The first explanation identifies the failure to resolve the issues in dispute as a key source of instability. The second explanation highlights the well-known problem of enforcement that often plagues agreements in an anarchic environment. The final argument considers the belligerents' incentives to renegotiate the terms of the settlement. Using a hazard model, I test hypotheses derived from each explanation with data on the duration of peace between dyads formerly at war between 1816 and 1992. I find little support for the resolution argument, only mixed support for the enforcement argument, and much more consistent support for the renegotiation argument.

Purpose Treatment of patellar tendinopathy/jumper’s knee with ultrasound-guided sclerosing injections or ultrasound-guided arthroscopic shaving has shown good clinical short-term results. Former studies indicate that the tendon thickness and structure stays unaffected after successful treatment. The aim of this study was to evaluate the sonographic findings and clinical outcome 3–5 years after treatment of patellar tendinopathy with ultrasound-guided sclerosing injections or arthroscopic shaving. Methods Fifty-seven patellar tendons (43 patients) with chronic patellar tendinopathy were evaluated, with ultrasound, colour Doppler (CD) and visual analogue scale (VAS) for pain and satisfaction with treatment, 3–5 years after treatment. Functional status was evaluated with a single question—“Back in full loading activity?” yes or no. Results At endpoint (mean 46 months), there was a significant decrease in anteroposterior thickness of the proximal patellar tendon in patients treated with ultrasound-guided arthroscopic shaving but not after sclerosing injections. Tendon structure had improved, and CD local blood flow had diminished significantly in both groups. There were good clinical results with a significant decrease in VAS for pain after sclerosing injections (VAS 64 ± 18 → 17 ± 23) with 74 % satisfied patients and also after arthroscopic shaving (VAS 77 ± 16 → 13 ± 23) with 80 % satisfied patients. There were no significant differences in VAS between groups. A significant correlation between low local blood flow and high patient satisfaction was found. Conclusions Tendon thickness decreased over time after ultrasound-guided arthroscopic shaving, and tendon structure and local blood flow decreased after both treatments. There were good, and similar, clinical results with both methods. Level of evidence III.

The following possible risk factors for leg injuries in female soccer players were studied: age, anatomical alignment, generalized joint laxity, thigh muscle torque, muscle flexibility, ligamentous laxity of the knee and ankle joints, recent injuries, and duration of soccer exposure. A total of 146 players from 13 teams in the second and third Swedish divisions underwent clinical examination, isokinetic measurements of quadriceps and hamstring torques, and testing of postural sway of the legs. All soccer‐related leg injuries resulting in absence from at least one scheduled practice session or game were recorded during one outdoor season (April–October). In 50 players there were 61 traumatic injuries, and 17 players sustained 19 overuse injuries. The overall injury incidence rate (traumatic and overuse) was 5.49/1000 h of soccer. Variables significantly increasing the risk of traumatic leg injuries included generalized joint laxity, low postural sway of the legs, hyperextension of the knee joint, and a low hamstring‐to‐quadriceps ratio during concentric action. Multivariate logistic regression showed hyperextension of the knee joint, a low postural sway, reduced H/Q ratio during concentric action, and a higher exposure to soccer to significantly increase the risk of traumatic leg injury. All five players who suffered an anterior cruciate ligament injury during the study period had a lower hamstring‐to‐quadriceps ratio during concentric action on the injured side than on their noninjured side.

Background: There is a high risk for anterior cruciate ligament (ACL) injuries in alpine skiers. To reduce or try to prevent these injuries, intrinsic and extrinsic risk factors need to be identified. Purpose: To identify possible intrinsic and extrinsic ACL injury risk factors among competitive adolescent alpine skiers. Study Design: Case-control study; Level of evidence, 3. Methods: Between 2006 and 2009, a cohort of 339 alpine ski students (176 male, 163 female) from Swedish ski high schools were prospectively observed in terms of ACL injuries. First-time ACL injuries were recorded. In September, prior to each ski season, the skiers were clinically examined according to a specific knee protocol. Results: Overall, 11 male and 14 female skiers sustained a total of 25 first-episode ACL injuries. The majority of injuries occurred in the left knee (P < .05). Skiers who had participated in alpine skiing for >13 years (hazard ratio, 0.83; 95% CI, 0.68-1.00; P < .05) had a reduced risk of sustaining an ACL injury. Eighteen ACL injuries occurred during training, 12 in the technical discipline of giant slalom, and 8 in slalom. Fourteen skiers reported not to be fatigued at all at the time of injury, and 8 skiers reported that they were somewhat fatigued. Conclusion: ACL injuries occurred more often in the left knee than the right. This should be taken into consideration in the design of ACL injury prevention programs. Those who reported a higher number of active years in alpine skiing showed a reduced risk of sustaining an ACL injury. No other factor among those studied could be identified as an independent risk factor for ACL injury.