Knee instability has been the focus of large number of studies over the last decade; however, a high incidence rate of injury still exists. The aim of this short report is to examine knee joint anatomy and physiology with respect to knee stability. Knee joint stability requires the integration of a complex set of anatomical structures and physiological mechanism. Compromising any of these structures leads to destabilisation and increased risk of injuries. This review highlights the structure and soft tissue of the knee that contribute to its stability and function. This introduction is part of the Journal of Functional Morphology and Kinesiology's Special Issue "The Knee: Structure, Function and Rehabilitation".

Abstract:Re-injury to a recently rehabilitated or operated knee is a common occurrence that can result in significant loss of function. Knee stability measures have been used to diagnose and assess knee stability before and after rehabilitation interventions. Here, we systematically review the literature and evaluate the different anterior-posterior and rotational knee stability measures currently in use. A computer-assisted literature search of the Medline, CINAHL, EMBASE, PubMed and Cochrane databases was conducted using keywords related to knee stability measures. In a second step, we conducted a manual search of the references cited in these articles to capture any studies that may have been missed in the searched databases. The literature search strategy identified a total of 574 potential studies. After revisiting the titles and abstracts, 34 full-text articles met the inclusion criteria and were included in this review. Most articles compared knee stability measures, whilst other studies assessed their sensitivity and specificity. Several techniques and devices used to measure knee stability are reported in the literature. However, there are only a limited number of quality studies where these techniques and/or devices have been evaluated. Further development and investigation with high quality study designs is necessary to robustly evaluate the existing devices/techniques.

Background Evidence-based practice (EBP) is necessary to improve the practice of physical therapy. However, a lack of knowledge and skills among physical therapists and the presence of barriers may hinder the implementation of EBP in the State of Kuwait. Objective The objectives of this study were to extensively (1) investigate attitudes toward EBP, (2) assess the current level of knowledge and skills necessary for EBP, and (3) identify the barriers to EBP among physical therapists in the State of Kuwait. Methods The following methods were used: (1) a previously validated self-reported questionnaire and (2) a face-to-face semistructured interview. The questionnaire, which was distributed to 200 physical therapists, examined the attitudes and beliefs of physical therapists about EBP; the interest in and motivation to engage in EBP; educational background, knowledge, and skills related to accessing and interpreting information; the level of attention to and use of the literature; access to and availability of information to promote EBP; and the perceived barriers to using EBP. The interview explored the factors that promote or discourage EBP. Descriptive statistics and logistic regression analyses were used. Results Of the 200 nonrandomly distributed questionnaires, 92% (184/200) were completed and returned. In general, the physical therapists had positive attitudes, beliefs, and interests in EBP. Their educational background, knowledge, and skills related to assessing and interpreting information were well-founded. The top 3 barriers included insufficient time (59.2%, 109/184), lack of information resources (49.4%, 91/184), and inapplicability of the research findings to the patient population (40.7%, 75/184). Conclusions EBP lacks support from superiors at work. Thus, identifying methods and strategies to support physical therapists in adopting EBP in the State of Kuwait is necessary.

Electrical stimulation (ES) and magnetic stimulation (MS), applied peripherally, may be used to elicit muscle contractions to increase muscle hypertrophy, increase muscle strength and reduce knee laxity in rehabilitation following injury. We aimed to examine the effect of a three-week exercise programme designed to induce muscle hypertrophy augmented by peripheral ES and MS. We hypothesised that the use of peripheral stimulation to augment voluntary drive during a resistance-training protocol would induce more repetitions thus leading to increased thigh circumference, muscle layer thickness, and quadriceps strength whilst decreasing knee laxity. Thirty healthy participants were divided randomly into either ES, MS or Control groups. Five resistance training sessions were carried out, consisting of four sets of quadriceps extensions. During the first three sets the participants performed eight repetitions at 85% of their 1-repetition maximum (1-RM). On the last set, the participants were instructed to perform the exercise until failure. The augmentation of peripheral stimuli allowed the MS and ES groups to continue to exercise producing, on average, 4 ± 2 and 7 ± 6 additional repetitions with ES and MS, respectively. Following the training, significant increases were observed for both 1-RM (p = 0.005) and muscle layer thickness (p = 0.031) whilst no change was observed in thigh circumference (p = 0.365). Knee laxity decreased (p = 0.005). However, there were no significant differences in the stimulation groups compared with control for any of these measurements. The additional repetitions elicited by stimulation after the point of failure suggests that peripheral electrical and/or magnetic stimulation may be useful as an adjunct for resistance training. However, this effect of resistance training augmented by peripheral stimulation on hypertrophy, strength and knee laxity may be small

BackgroundThe anterior cruciate ligament (ACL) plays an important role in anterior knee stability by preventing anterior translation of the tibia on the femur. Rapid translation of the tibia with respect to the femur produces an ACL-hamstring stretch reflex which may provide an object measure of neuromuscular function following ACL injury or reconstruction. The aim of this study was to determine if the ACL-hamstring stretch reflex could be reliably and consistently obtained using the KT-2000 arthrometer.MethodsA KT-2000 arthrometer was used to translate the tibia on the femur while recording the electromyography over the biceps femoris muscle in 20 participants, all with intact ACLs. In addition, a sub-group comprising 4 patients undergoing a knee arthroscopy for meniscal pathology, were tested before and after anaesthetic and with direct traction on the ACL during arthroscopy. The remaining 16 participants underwent testing to elicit the reflex using the KT-2000 only.ResultsA total number of 182 trials were performed from which 70 trials elicited stretch reflex (38.5 %). The mean onset latency of the hamstring stretch reflexes was 58.9 ± 17.9 ms. The average pull force was 195 ± 47 N, stretch velocity 48 ± 35 mm/s and rate of force 19.7 ± 6.4 N/s.ConclusionsBased on these results, we concluded that the response rate of the anterior cruciate ligament-hamstring reflex is too low for it to be reliably used in a clinical setting, and thus would have limited value in assessing the return of neuromuscular function following ACL injuries.

Background: The anterior cruciate ligament (ACL) plays an important role in anterior knee stability by preventing anterior translation of the tibia on the femur. Rapid translation of the tibia with respect to the femur produces an ACL-hamstring stretch reflex which may provide an object measure of neuromuscular function following ACL injury or reconstruction. The aim of this study was to determine if the ACL-hamstring stretch reflex could be reliably and consistently obtained using the KT-2000 arthrometer. Methods: A KT-2000 arthrometer was used to translate the tibia on the femur while recording the electromyography over the biceps femoris muscle in 20 participants, all with intact ACLs. In addition, a subgroup comprising 4 patients undergoing a knee arthroscopy for meniscal pathology, were tested before and after anaesthetic and with direct traction on the ACL during arthroscopy. The remaining 16 participants underwent testing to elicit the reflex using the KT-2000 only. Results: A total number of 182 trials were performed from which 70 trials elicited stretch reflex (38.5 %). The mean onset latency of the hamstring stretch reflexes was 58.9 ± 17.9 ms. The average pull force was 195 ± 47 N, stretch velocity 48 ± 35 mm/s and rate of force 19.7 ± 6.4 N/s. Conclusions: Based on these results, we concluded that the response rate of the anterior cruciate ligament-hamstring reflex is too low for it to be reliably used in a clinical setting, and thus would have limited value in assessing the return of neuromuscular function following ACL injuries.

BACKGROUND Evidence-based practice (EBP) is necessary to improve the practice of physical therapy. However, a lack of knowledge and skills among physical therapists and the presence of barriers may hinder the implementation of EBP in the State of Kuwait. OBJECTIVE The objectives of this study were to extensively (1) investigate attitudes toward EBP, (2) assess the current level of knowledge and skills necessary for EBP, and (3) identify the barriers to EBP among physical therapists in the State of Kuwait. METHODS The following methods were used: (1) a previously validated self-reported questionnaire and (2) a face-to-face semistructured interview. The questionnaire, which was distributed to 200 physical therapists, examined the attitudes and beliefs of physical therapists about EBP; the interest in and motivation to engage in EBP; educational background, knowledge, and skills related to accessing and interpreting information; the level of attention to and use of the literature; access to and availability of information to promote EBP; and the perceived barriers to using EBP. The interview explored the factors that promote or discourage EBP. Descriptive statistics and logistic regression analyses were used. RESULTS Of the 200 nonrandomly distributed questionnaires, 92% (184/200) were completed and returned. In general, the physical therapists had positive attitudes, beliefs, and interests in EBP. Their educational background, knowledge, and skills related to assessing and interpreting information were well-founded. The top 3 barriers included insufficient time (59.2%, 109/184), lack of information resources (49.4%, 91/184), and inapplicability of the research findings to the patient population (40.7%, 75/184). CONCLUSIONS EBP lacks support from superiors at work. Thus, identifying methods and strategies to support physical therapists in adopting EBP in the State of Kuwait is necessary.