Caroline Mouton

Static rotational knee laxity in anterior cruciate ligament injuries.

PurposeThe purpose was to provide an overview of the non-invasive devices measuring static rotational knee laxity in order to formulate recommendations for the future.ResultsEarly cadaver studies provided evidence that sectioning the anterior cruciate ligament (ACL) led to an increase of static rotational knee laxity of approximately 10–20% between full extension and 30° of knee flexion. Sections of the menisci or of the peripheral structures induced a much higher increase in rotation. This supported the hypothesis that static rotation measurements might be useful for the diagnosis of ACL or associated injuries. In vivo evaluations with measurement devices are relatively new. Several articles were published during the last decade with many different devices and important differences were seen in absolute rotational knee laxity between them. This was due to the varying precision of the devices, the variability in patient positioning, the different methods of measurement, examination protocols and data analysis. As a consequence, comparison of the available results should be performed with caution. Nevertheless, it has been established that rotational knee laxity was greater in females as compared to males and that the inter-subject variability was high. For this reason, it will probably be difficult to categorise injured patients preoperatively, and the interpretation of the results should probably be limited to side-to-side differences.ConclusionFuture studies will show whether rotational laxity measurements alone will be sufficient to provide clinically relevant data or if they should be combined to static sagittal laxity measurements.

Noninjured Knees of Patients With Noncontact ACL Injuries Display Higher Average Anterior and Internal Rotational Knee Laxity Compared With Healthy Knees of a Noninjured Population

Background: Excessive physiological anterior and rotational knee laxity is thought to be a risk factor for noncontact anterior cruciate ligament (ACL) injuries and inferior reconstruction outcomes, but no thresholds have been established to identify patients with increased laxity. Purpose: (1) To determine if the healthy contralateral knees of ACL-injured patients have greater anterior and rotational knee laxity, leading to different laxity profiles (combination of laxities), compared with healthy control knees and (2) to set a threshold to help discriminate anterior and rotational knee laxity between these groups. Study Design: Case-sectional study; Level of evidence, 3. Methods: A total of 171 healthy contralateral knees of noncontact ACL-injured patients (ACL-H group) and 104 healthy knees of control participants (CTL group) were tested for anterior and rotational laxity. Laxity scores (measurements corrected for sex and body mass) were used to classify knees as hypolax (score <–1), normolax (between −1 and 1), or hyperlax (>1). Proportions of patients in each group were compared using χ2 tests. Receiver operating characteristic curves were computed to discriminate laxity between the groups. Odds ratios were calculated to determine the probability of being in the ACL-H group. Results: The ACL-H group displayed greater laxity scores for anterior displacement and internal rotation in their uninjured knee compared with the CTL group (P < .05). Laxity profiles were different between the groups for the following associations: normolax in anterior displacement/hypolax in internal rotation (6% [ACL-H] vs 15% [CTL]; P = .02) and hyperlax in anterior displacement/normolax in internal rotation (27% [ACL-H] vs 10% [CTL]; P < .01). The laxity score thresholds were 0.75 for anterior laxity and −0.55 for internal rotation. With both scores above these thresholds, a patient was 3.18-fold more likely to be in the ACL-H group (95% CI, 1.74-5.83). Conclusion: The healthy contralateral knees of patients with noncontact ACL injuries display different laxity values both for internal rotation and anterior displacement compared with healthy control knees. The identification of knee laxity profiles may be of relevance for primary and secondary prevention programs of noncontact ACL injuries.

How to get a better picture of the ACL injury problem? A call to systematically include conservatively managed patients in ACL registries

ACL injury registries have provided substantial new knowledge to sports medicine/sports physio. Registries aggregate a large amount of individual data,1 sometimes via collaboration among different institutions.2 Nevertheless, a systematic recording of ACL-injured patients is non-existent or at its very beginnings in many countries. Owing to the variety and available resources of different healthcare systems, organising registries on a national level is difficult. In Europe, the pioneering Scandinavian countries were followed by a private initiative from the UK, which started in 2014.3 Currently, efforts to set up data collection are also being made in the German-speaking countries. Registry data are helpful in at least three ways: (1) in improving treatment outcomes through feedback to the treating physicians and institutions, (2) in detecting unreliable procedures and devices and (3) in identifying outcome-associated prognostic factors.4 Despite this focused …

Objective measurements of static anterior and rotational knee laxity

Several devices allow to measure anterior and rotational static knee laxity. To date, the use of rotational laxity measurements in the daily clinical practice however remains to be improved. These measurements may be systematically integrated to the follow-up of knee injuries. Physiologic laxity measurements may particularly be of interest for the identification of risk factors in athletes. Furthermore, knee laxity measurements help to improve the diagnosis of knee soft tissue injuries and to follow up reconstructions. Further prospective follow-ups of knee laxity in the injured/reconstructed knees are however required to conclude on the best treatment strategy for knee soft tissue injuries.

Patient demographic and surgical characteristics in anterior cruciate ligament reconstruction: a description of registries from six countries

Objective Findings from individual anterior cruciate ligament reconstruction (ACLR) registry studies are impactful, but how various registries from different countries compare with different patient populations and surgical techniques has not been described. We sought to describe six ACLR registry cohorts to understand variation across countries. Methods Five European registries and one US registry participated. For each registry, all primary ACLR registered between registry establishment through 31December 2014 were identified. Descriptive statistics included frequencies, proportions, medians and IQRs. Revision incidence rates following primary ACLR were computed. Results 101 125 ACLR were included: 21 820 in Denmark, 300 in Luxembourg, 17 556 in Norway, 30 422 in Sweden, 2972 in the UK and 28 055 in the US. In all six cohorts, males (range: 56.8%–72.4%) and soccer injuries (range: 14.1%–42.3%) were most common. European countries mostly used autografts (range: 93.7%–99.7%); allograft was most common in the US (39.9%). Interference screw was the most frequent femoral fixation in Luxembourg and the US (84.8% and 42.9%), and suspensory fixation was more frequent in the other countries (range: 43.9%–75.5%). Interference was the most frequent tibial fixation type in all six cohorts (range: 64.8%–98.2%). Three-year cumulative revision probabilities ranged from 2.8% to 3.7%. Conclusions Similarities in patient demographics and injury activity were observed between all cohorts of ACLR. However, graft and fixation choices differed. Revision rates were low. This work, including >100 000 ACLR, is the most comprehensive international description of contemporary practice to date.

Clinical course and recommendations for patients after anterior cruciate ligament injury and subsequent reconstruction: A narrative review

Almost all athletes who have suffered an anterior cruciate ligament (ACL) injury expect a full return to sports at the same pre-injury level after ACL reconstruction (ACLR). Detailed patient information on the reasonable outcomes of the surgery may be essential to improve patient satisfaction. Pre-operative rehabilitation before ACLR should be considered as an addition to the standard of care to maximise functional outcomes after ACLR. We propose an optimised criterion-based rehabilitation programme within a biopsychosocial framework. No benchmark exists for evaluating return-to-sport (RTS) readiness after ACLR. Therefore, the authors propose a multi-factorial RTS test battery. A combination of both physical and psychological elements should be included in the RTS test battery. There is need for shared decision-making regarding RTS. Cite this article: EFORT Open Rev 2017;2:410-420. DOI: 10.1302/2058-5241.2.170011

Patellar Instability in Football Players

Patellar instability is characterized by an abnormal, most of the time, lateral movement of the patella in the trochlear groove of the femur. The incidence rate has not yet been reported in football players. However, football is one of the most common sports to induce patellar dislocations as it involves twisting movements and contacts between players or with the ground. Many factors such as age, exercise, sex, family history, previous dislocation, and bony and soft tissue parameters can impact the risk of a patellar dislocation. The clinical examination therefore starts with an anamnesis including the exact mechanism and the family history of patellar dislocation. The physical examination must include palpation of relevant patellofemoral soft tissues, as well as evaluation of mediolateral mobility, apprehension, and J sign tests. To obtain a detailed description of the pathology, X-ray and CT scans or MRI are essential. The risk for recurrent dislocations is closely related to the patient’s age and the patellofemoral morphology. Nonoperative treatment is usually preferred for a primary dislocation without major structural risk factors (malalignment, dysplasia) or structural damage (static subluxation of the patella, osteochondral fragments). Conversely, surgery is recommended for secondary and recurrent dislocations. The current rehabilitation strategies aim to regain full range of motion, to stabilize patellar tracking and to strengthen the quadriceps. Players are allowed to return to sport when these rehabilitation targets are achieved, usually within 3–6 months after injury/surgery. However, many of them cannot return to their preoperative level.

Return to Sports, the Use of Test Batteries

Athletes, and in particular young athletes, have high demands in terms of return to sports (RTS) after an ACL reconstruction (ACLR). Despite the development of RTS guidelines over the recent years, there are still more questions than answers on the most optimal RTS criteria after ACLR. Clinicians and researchers have become increasingly aware of the high incidence of second ACL injury that exceeds 23% in only the first year following RTS. This poses the question as to how clinicians determine when an athlete is ready for RTS in light of the associated risk(s) involved.

Static Rotational Knee Laxity Measurements

Static rotational knee laxity measurements have the advantages of precisely quantifying laxity and are thus potentially more objective than manual tests. Moreover, they can help to establish the diagnosis of knee injuries and to evaluate the success of reconstruction procedures after surgical intervention. As a consequence, they may systematically be part of follow-up to knee injuries (i.e. anterior cruciate ligament injuries). Numerous devices to measure knee rotation in a non-invasive manner exist. Although further efforts are necessary to improve the use of rotational laxity measurements in daily clinical practice, existing data on static rotational knee laxity measurements is encouraging to further investigate it in healthy and injured persons. Rotational knee laxity measurements allow (1) for the evaluation of the physiological knee laxity as a risk factor for knee injuries and poor reconstruction outcomes, (2) for the diagnosis of knee injuries (i.e. anterior cruciate ligament injuries) and (3) to follow knee ligament reconstructions postoperatively. The lack of knowledge of rotational knee laxity measurements in injured/reconstructed knees, however, prevents us to conclude the best treatment or reconstruction techniques. The present chapter aims to analyse the current knowledge and the potential for rotational knee laxity measurements to follow and individualise care for knee injuries and diseases.

Instrumented Static Laxity Evaluation

Knee laxity is a highly complex issue, depending on an individual’s soft tissue quality and bony configuration. It can be evaluated both in a single and in multiple directions or statically and dynamically. Knee laxity is difficult to assess clinically, because it is highly dependent on the examiner’s experience, which in addition does not allow a precise quantification of knee laxity. Therefore, several devices have been developed to measure static knee laxity. In the early stages, they were limited to measurements in the sagittal plane. Over the last decade, static rotational laxity measurement devices have been added and are currently under development. Despite the fact that instrumented laxity assessments have been performed over several decades, limited knowledge is available on multidirectional static laxity assessments in large populations. Laxity evaluations in large groups followed over time could allow (1) for the study of physiological laxity and risk factors for knee injuries, (2) to confirm the diagnosis of soft tissue injuries, (3) to help distinguish between the different subtypes of anterior cruciate ligament (ACL) tears as well as associated injuries and (4) to follow patients who have had ACL reconstruction. This chapter will provide an overview of currently existing laxity devices and new findings on static knee laxity evaluations. Despite recent advances, there is still much work to be done to improve the use of arthrometers in the daily clinical practice.