Closed Kinetic Chain Research Articles

Effects of Isokinetic Strength Exercise of the Hemiparetic Knee Joint on Lower Extremity Sensorimotor and Gait Functions in Patients With Chronic Stroke: Open Kinetic Chain Versus Closed Kinetic Chain

Background: After stroke, in order to improve gait function, it is necessary to increase the muscle strength and to enhance the propriocetive function of the lower extremity. Objects: This study aimed to compare the effects of open kinetic chain (OKC) versus closed kinetic chain (CKC) isokinetic exercise of the hemiparetic knee using the isokinetic equipment on lower extremity sensorimotor function and gait ability in patients with chronic stroke. Methods: Thirty participants with chronic hemiplegia (> 6 months post-stroke) were randomly divided into 2 equal groups: CKC group and OKC group. Patients from both groups attended conventional physiotherapy sessions 3 times a week for 6 weeks. Additionally, subjects from the CKC group performed isokinetic exercise using the CKC attachment, while those from the OKC group performed isokinetic exercise using the OKC attachment. The isokinetic knee and ankle muscles strength, position sense of the knee joint, and spatiotemporal gait parameters were measured before and after interventions. Results: The knee muscles peak torque/body weight (PT/BW) and hamstring/quadriceps (H/Q) ratio significantly increased in both groups (p<.01). In particular, ankle plantarflexors PT/BW, position sense of the knee, gait velocity, and spatial gait symmetry significantly improved in the CKC group (p<.01, p<.05, p<.01, and p<.01, respectively). Conclusion: CKC isokinetic exercise can be an effective therapeutic intervention for the improvement of sensorimotor function of the lower extremity and gait functions, such as gait velocity and symmetry. CKC position in isokinetic strength training is effective to improve functional ability in patients with chronic stroke.

Is there a relation between rotator cuff injury and core stability?

Strong core stabilization not only minimizes the load on the vertebral column, but also improves strength and endurance of peripheral joints, and enables the energy transfer to distal segments. Despite the current interest surrounding core stability, none of the studies investigated the effect of core stability on the formation of rotator cuff tear or healing after repair. To determine the relationship between core stability and upper extremity functional performance in patients who underwent rotator cuff repair surgery and to compare those with healthy subjects of similar age. Patients who underwent rotator cuff repair (RC repair group, n= 58 patient) and healthy subjects of the similar age group (control group, n= 114) were included in the study. The mean age was 55.03 ± 9.84 years in the RC repair group and 52.71 ± 6.31 years in the control group. The RC repair group took standardized rehabilitation. The rehabilitation program did not include core strength and stability exercise. Core endurance was assessed with Flexor Endurance, Prone Bridge and Supine bridge test. Disabilities of the Arm, Shoulder and Hand (DASH), Short Form-36 (SF-36) and the Close Kinetic Chain Upper Extremity Stability (CKCUES) test were used to evaluate the upper extremity functional performance. The core endurance (prone and supine bridge test) of the control group was statistically significantly better than the RC repair group (p⩽ 0.005). The DASH-T, SF-36 and CKCUES scores of the control group were also statistically significantly better. The neuromuscular system should be considered as a whole, and addition of the core stabilization exercises to an effective rehabilitation program after RC repair surgery may be beneficial.

Early Regain of Function and Proprioceptive Improvement Following Knee Arthroplasty.

Techniques that allow early muscle activation, such as closed kinetic chain (CKC) and open kinetic chain (OKC) exercises, may play a beneficial role in the early rehabilitation of the reconstructed knee. However, current rehabilitation regimens have not been shown to reverse post-operative quadriceps activation failure and weakness. To investigate whether patients who use a continuous active motion (CAM) device that follows closed kinetic chain principles have better early post-operative functional improvements than patients who use a continuous passive motion (CPM) device that follows the principles of open kinetic chain principles. A prospective randomized controlled trial with non-blinded study staff. A tertiary care clinic at a teaching hospital. A total of 110 patients signed the consent form and 83 patients participated in the study. Patients were randomly assigned to use either the CPM device for 4 hours daily for 3 weeks (control group), or a CAM device for 3 sessions of 20 minutes for 3 weeks (intervention group), starting 24 hours after knee replacement surgery.The primary outcome measure was to identify the superiority, inferiority, or equivalence of one device at week 4 after knee arthroplasty using various functional outcome measures such as kinesthesia, quadriceps strength, coordination, general orthopaedic outcome measures and narcotic consumption. At 4 weeks, all outcome measurements were comparable between the two groups, with the exception of sit-to-stand test: in the treatment group the time was significantly shorter compared to the control group (P=0.016). Balance was significantly better in both control (P=0.001) and treatment group (P=0.032) compared to prior surgery. Most clinical centers would like to expedite functional recovery of knee arthroplasty patients without increasing the risk of falls. We observed balance and kinesthesia improvements after surgery using either device which may be important to benefit fast recovery programs. Further research is warranted to see whether additional active closed kinetic chain exercised following knee replacement surgery could improve specific functional outcomes such the observed sit-to-stand test. I.

The relationship between core endurance and upper extremity performance in sedentary collegiate males

Core muscles contribute to general spine stabilization when the trunk is exposed to flexion and extension moments. It is thought that movements begin from the center of the body (called the “powerhouse” or “core”) and flow outward to the extremities, and a strong core strengthens the whole body. Few studies have examined the relationship between core endurance and upper extremity performance and most of the studies have been done in athletes. Thus, the purpose of this study was to investigate relationships between core endurance, and upper extremity performance in sedentary collegiate males. Sedentary collegiate males who had not suffered any orthopedic injury in the past year were enrolled the study. Core endurance (CE) was evaluated using Trunk Extensor Test, Bilateral Side Bridge Tests, and The Core Muscle Strength and Stability test. The results of the core endurance tests were compared with several upper extremity performance measurements: The Upper Quarter Y Balance Test (bilaterally in medial, inferolateral, and superolateral directions-UQYBT), Close Kinetic Chain Upper Extremity Stability Test (CKCUES test), medicine ball throws test (forward, reverse, right, and left in static and dynamic positions), hand grip strength, and Nelson hand reaction test. Eighty-three males were assessed during the study. Their mean age was 22.07 ± 1.89 year (range: 18–25) and mean body mass index was 23.77 ± 3.26 kg/m 2 (range: 17.67–36.11). We observed low correlations between the CE tests and UQYBT ( r range = 0.220 − 0.393, P < 0.05) but no correlations between the CE and hand grip strength and Nelson hand reaction test. CKCUES and medicine ball throws test (nondominant side in dynamic position) correlated with side bridge test, r = 0.279 and r = 0.240, respectively ( P < 0.05). The results of this study imply that the core endurance is related to the upper extremity performance in closed kinetic chain but not with open kinetic chain functions, where only distal extremity performance is present.

열린사슬운동과 닫힌사슬운동이 큰가슴근과 위팔세갈래근의 근활성도에 미치는 영향

열린사슬운동과 닫힌사슬운동이 큰가슴근과 위팔세갈래근의 근활성도에 미치는 영향

The Effect of Open- Versus Closed-Kinetic-Chain Exercises on Anterior Tibial Laxity, Strength, and Function Following Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis.

Background There is controversy surrounding the early use of open-kinetic-chain (OKC) quadriceps-strengthening exercises following anterior cruciate ligament reconstruction (ACLR) due to the belief that increased strain on the graft could cause damage. Objectives To determine whether OKC quadriceps exercises result in differences in anterior tibial laxity, strength, function, quality of life, or adverse events in the ACLR population, when compared to closed-kinetic-chain (CKC) quadriceps exercises. Methods Seven electronic databases (MEDLINE, Embase, AMED, CINAHL, SPORTDiscus, PEDro, and the Cochrane Central Register of Controlled Trials) were searched through April 2017. A systematic review with meta-analysis was conducted on randomized controlled trials comparing OKC versus CKC exercises following ACLR. Outcomes of interest were tibial laxity, strength, and function. A methodological quality assessment of the included studies was completed, and the results were synthesized using meta-analysis and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Results Ten studies were included in the review. The meta-analysis demonstrated low- to moderate-quality evidence of no between-group differences in anterior tibial laxity, strength, or patient-reported function at any time point. Meta-analysis was unable to be performed for functional outcomes. Conclusion There was limited to moderate-quality evidence of no difference in anterior tibial laxity, strength, patient-reported function, or physical function with early or late introduction of OKC exercises in the ACLR population, when compared to CKC exercises, at all follow-up time points. Level of Evidence Therapy, level 1a. J Orthop Sports Phys Ther 2018;48(7):552-566. Epub 23 Apr 2018. doi:10.2519/jospt.2018.7656.

열린사슬운동과 닫힌사슬운동이 큰가슴근과 위팔세갈래근의 근활성도에 미치는 영향

열린사슬운동과 닫힌사슬운동이 큰가슴근과 위팔세갈래근의 근활성도에 미치는 영향

The Effects of Open versus Closed Kinetic Chain Exercises on Ankle Joint Function in Athletes with Chronic Ankle Instability

Objective: Lateral ankle sprains are common sport injuries that often result in structural and functional alterations leading to chronic ankle instability (CAI). Insufficiencies in proprioception, neuromuscular control, and strength are suggested as contributing factors to CAI. Open Kinetic Chain (OKC) and Closed Kinetic Chain (CKC) exercises often constitute the core of ankle specific training before progression to advanced training. Though commonly used in the management of CAI, there is no consensus regarding their efficacy on physical therapy outcomes. The purpose of this study was to compare the effect of OKC and CKC exercises on dynamic postural control, self-reported function, and subjective sense of instability in subjects with CAI. Methods: Subjects with unilateral CAI were randomly assigned into three groups: OKC (n=5), CKC (n=6), and control (n=6). Outcome measures included star excursion balance test (SEBT) reach distance, center of pressure (COP) sway velocity, sway area, and path length; and Foot and Ankle Ability Measure-Sport Subscale. Intervention groups completed 6 weeks of exercises. Also, subjects completed a global rating of change (GROC) form at week 6 post-intervention. Results: Following intervention, both OKC and CKC groups had significant improvements in the outcome measures, indicating an improvement in dynamic postural control and subjective function; however, CKC had greater improvements than OKC. The control group did not show improvements. GROC revealed a significant difference in median score for CKC group when compared to OKC and control groups (p=0.04 and p=0.03, respectively). Conclusion: The 6-week of OKC and CKC exercise programs improved parameters of postural control and subjective function in CAI subjects. CKC exercises, however, were more effective than OKC exercises. Hence, exercise programs should become more functional and task oriented. Further research is needed in a larger cohort of subjects to determine effects of both training programs on ankle joint injury risk factors.

The Effect of Sling Exercise Therapy with Vibration Balls on Upper Limb Muscle Activity for Paraplegia-Spinal Cord Injury

Objective: The purpose of the present study is to investigate the effect of a muscle activity by applying the complex exercise method of sling in accordance with the provision of various vibration intensities for paraplegia-spinal cord injury. Method: The subjects of the study were 15 men in their 40s and 50s with lower limb disabilities and low potential risk, who were randomly divided into a sling exercise group (SG n=4), a sling with low frequency vibration group (SLVG n=4), a sling with mid-frequency vibration group (SMVG n=4), and a sling with high frequency group (SHVG n=4) in accordance with the provision of slings and vibration stimuli. The vibratory intensity provided was divided into low frequency (30 Hz), mid-frequency (50 Hz), and high frequency (70 Hz). The anterior deltoid (AD), the posterior deltoid (PD), the pectoralis major (PM), the upper trapezius (UT), the latissimus dorsi (LD), and the multifidus (MF) were measured to compare and analyze muscle activity. Results: The closed kinetic chain (CKC) exercise to the shoulder joint showed higher muscle activity in most muscles for the SMVG, and statistically significant differences in the anterior deltoid (AD), the pectoralis major (PM), and the multifidus (MF) in particular. Conclusion: The intermediate frequency (50 Hz) string vibration was the effective vibration stimuli for Closed kinetic chain (CKC) exercises.

Range of Motion Changes in Female Elite Swimmers Throughout a Competitive Season

Upper extremity injuries are the most common injury in swimming athletes specifically in the collegiate setting. Females in particular, are more likely to suffer these injuries when comparing to male collegiate swimmers. “Swimmer Shoulder”, a generic term for overuse shoulder injuries in the swimming population occurs with high rate and intensity of training. Significant factors that have been found to contribute to this pathology are deficits in internal rotation, lack of stability, and increased demands on the shoulder. The aim for this clinical outcomes project was to evaluate changes in range of motion (ROM) total arc of the shoulder, and patient-perceived function in female elite swimmers throughout a competitive season. Shoulder total arc ROM was measured passively with the student-athlete supine. A digital inclinometer was used to make it simpler for the clinician to assess ROM on their own. The Kerlan-Jobe Orthopedic Clinic Shoulder and Elbow Score (KJOC) was used to measure self-perceived upper extremity function in sport. It consisted of a set of demographic and participation questions followed by 10 visual analogue scale questions about upper extremity function during sport. Upper extremity stability was also measured using the closed-kinetic chain upper extremity stability test (CKCUE). Results showed shoulder ROM (total arc) restrictions occurred during times of increased training intensity and volume. When patients had smaller total arc measurements, the student-athletes reported lower KJOC scores for sport related function. There was an increase in ROM at a time where intensity, and distance of training were decreased. Overall upper extremity stability gradually improved over the course of a competitive season.

What Is the Association between an Anteriorly Tilted Pelvis and Trendelenburg Gait?

Lower back pain (LBP) is a widespread, painful medical condition that has been plaguing society for many years. Present conservative rehabilitation focus is on lumbo-pelvic hip stability exercises in individual planes. However, a functional integrative rehabilitative approach addressing lumbo-pelvic misalignment in the sagittal (anteriorly tilted pelvis) and frontal (Trendelenburg gait) planes has not been presented. The aforementioned patho-biomechanical conditions and their management are often discussed estranged from each other rather than functionally integrated. This paper serves as a short communication which discusses the lumbo-pelvic anatomy, identifies the anatomical and biomechanical associations between the anteriorly tilted pelvic and Trendelenburg gait. Through an analysis of relevant literature, recommendations were made on the improvement of flexibility of the hip flexors, taut iliofemoral and pubofemoral ligaments to resolve the primary abnormal force-couple, with improved flexibility of the erector spinae and quadratus lumborum to resolve the secondary abnormal force-couple. In addition, improved flexibility of the hip flexors should coincide with closed-kinetic chain concentric strengthening of the ipsi-lateral hip abductors and contralateral external obliques. Patient education is also needed for self-re-alignment of the lower extremity to a neutral position and neutral foot stance. Biokineticists/exercise therapists should also review the patient’s gait biomechanics to determine whether sartorius synergistic dominance is in play. In conclusion, the association between an anteriorly tilted pelvis and Trendelenburg gait, is in regard to taut anterior acetabulofemoral ligaments and femoral retroversion torsion angle that is both preceded and followed by the biomechanical influence of various anatomical structures. These anatomical and biomechanical factors must be evaluated by the biokineticists/exercise therapists before prescribing a rehabilitative programme to ensure successful rehabilitation of lumbo-pelvic hip complex.

A Four-Week Upper-Extremity Exercise Program on a Balance Device Improves Power and Stability in Collegiate Golfers

Relatively little research has been conducted examining the physical characteristics that are important to a golfer’s performance. The investigators studied whether a series of upper-extremity exercises on a balance device would significantly improve upper- extremity stability and power in collegiate golfers. A total of 23 collegiate golfers (ages: 20.4 ± 1.4 years, height: 67.7 in ± 6.6 in, weight: 171.8 lb. ± 87.6 lb.) participated in the study. A two group non-equivalent pre-test/post-test design was selected for this study. Testing included shoulder flexion, hyper-extension (shoulder flexibility), and a Closed-Kinetic Chain Upper-Extremity Stability test (Upper-Extremity stability and power). Testing was conducted before and after a 4-week upper-extremity exercise conducted on a balance device. An independent t-test was selected to analyze differences if any between the experimental and control group. The experimental group revealed a significant improvement in upper-extremity power (p=0.01) and stability (p=0.01). The shoulder flexibility for the experimental group demonstrated no significance (p=0.058) in the left shoulder hyperextension but showed significant value (p=0.033) in the right shoulder hyperextension. The control group demonstrated a significant (p=0.044) decrease in shoulder flexion in the right shoulder. The results demonstrate that specific upper-extremity exercises on a balance device do improve upper-extremity power, upper-extremity stability, and over-head shoulder flexibility within 4 weeks.

PENAMBAHAN KINESIOLOGY TAPE PADA PELATIHAN CLOSED KINETIC CHAIN (CKC) DAN STRETCHING LEBIH BAIK DALAM MENURUNKAN EXCESSIVE Q-ANGLE PADA WANITA

Background: Q-angle is the angle between the quadriceps and patellar tendon and showing the angle of the quadriceps muscle tension. Pelvic widening in women does not occur in men who lead the Q-angle in women begins to enlarge during adolescence than men. Purpose: The purpose of this study was to compare the addition of kinesiology tape on CKC training and stretching without additional kinesiology tape on CKC training and stretching in women. Methods: This research was a randomized experimental design with pre-test and post-test group design. The sample contain by 24 people divided into two groups of 12 people each. Treatment group with the addition of kinesiology tape on CKC training and stretching, while the control group only CKC training and stretching. This research was conducted for 8 weeks, 2 times in a week. The data collected by the Q-angle measured using a goniometer at the time before and after treatment. Result: The results of data analysis using the Wilcoxon Signed Ranks Test, Q-angle was obtained with p = 0.002 for the different treatment groups with an average of 12.25 and in control group acquired Q-angle, with p = 0.002 with 6.416 average difference, and different 47.59% with treatment group. Mann-Whitney test results the average of difference of decreasing of treatment group is 18.5 and the average of difference of control group is 6.5 different 64.86% with treatment group, showed that there were significant differences in the decrease in Q-angle between the two groups with the result p = 0.001 (p &lt;0.05). Conclusion: Conclusions of research are: the addition of kinesiology tape on the training of Closed Kinetic Chain (CKC) and stretching better in reducing excessive Q-angle in women. Suggestion: For the next research suggest to add dependent variables as: muscle strength, functional and speed of muscle contraction of Vastus Medial Oblique (VMO), individual addressing treatment, and use x-ray as measurement tool.

A Systematic Review of ACL Reconstruction Rehabilitation

Background: Anterior Cruciate Ligament (ACL) reconstruction is a well-known surgical knee procedure performed by orthopaedic surgeons. There is a general consensus for the effectiveness of a postoperative ACL reconstruction rehabilitation program, however there is little consensus regarding the optimal components of a program Objective of the Study: to assess the merits and demerits of current ACL reconstruction rehabilitation programs and interventions based on the evidence supported by previously conducted systematic reviews. Methods: a Systematic search in the scientific database (Medline, Scopus, EMBASE , and Google Scholer) between 1970 and 2017 was conducted for all relevant Systematic reviews discussing the primary endpoint ( ACL reconstruction rehabilitation ) studies were analyzed and included based on the preset inclusion and exclusion criteria. Study screening and quality was assessed against PRISMA guidelines and a best evidence synthesis was performed. Results: the search results yielded five studies which evaluated eight rehabilitation components (bracing, Continuous passive motion (CPM), neuromuscular electrical stimulation (NMES), open kinetic chain (OKC) versus closed kinetic chain (CKC) exercise, progressive eccentric exercise, home versus supervised rehabilitation, accelerated rehabilitation and water based rehabilitation). A strong evidence suggested no added benefit of short term bracing (0-6 weeks post-surgery) compared to standard treatment. Whilst a moderate evidence reinforced no added advantage of continuous passive motion to standard treatment for boosting motion range. Furthermore, a moderate evidence of equal effectiveness of closed versus open kinetic chain exercise and home versus clinic based rehabilitation, on a range of short term outcomes. There was inconsistent or limited evidence for some interventions including: the use of NMES and exercise, accelerated and non-accelerated rehabilitation, early and delayed rehabilitation, and eccentric resistance programs after ACL reconstruction. Conclusion: short term post-operative bracing and continuous passive motion (CPM) introduce no benefit over standard treatment and thus not recommended. A moderate evidence suggested equal efficiency for 1) CKC and OKC are equally effective for knee laxity, pain and function, at least in the short term (6-14 weeks) after ACL reconstruction and 2) home based and clinic based rehabilitation. Nevertheless, the degree of physiotherapy input remains unclear.

Differences Between Open and Closed-Kinetic Chain Measurements for Assessing Bilateral Strength Deficits

Differences Between Open and Closed-Kinetic Chain Measurements for Assessing Bilateral Strength Deficits

Open versus Closed Kinetic Chain Exercises following an Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-Analysis

Background There is no consensus on whether closed kinetic chain (CKC) or open kinetic chain (OKC) exercises should be the intervention of choice following an anterior cruciate ligament (ACL) injury or reconstruction. Methods A systematic search identified randomized controlled trials of OKC versus CKC exercise training in people who had undergone ACL reconstructive surgery. All published studies in this systematic review were comparisons between OKC and CKC groups. Results Seven studies were included. Lysholm knee scoring scale was not significantly different between OKC and CKC exercise patients: MD: −1.03%; CI: −13.02, 10.95; p value = 0.87 (Chi2 = 0.18, df = 1, and p value = 0.67). Hughston clinic questionnaire scores were not significantly different between OKC and CKC exercise patients: MD: −1.29% (−12.02, 9.43); p value = 0.81 (Chi2 = 0.01, df = 1, and p value = 0.93). Conclusions While OKC and CKC may be beneficial during ACL surgical rehabilitation, there is insufficient evidence to suggest that either one is superior to the other.

Validity and Reliability of a Digital Inclinometer to Assess Knee Joint-Position Sense in a Closed Kinetic Chain

Knee joint position sense (JPS) is a key parameter for optimum performance in many sports but is frequently negatively affected by injuries and/or fatigue during training sessions. Although evaluation of JPS may provide key information to reduce the risk of injury, it often requires expensive and/or complex tools that make monitoring proprioceptive deterioration difficult. To analyze the validity and reliability of a digital inclinometer to measure knee JPS in a closed kinetic chain (CKC). The validity and intertester and intratester reliability of a digital inclinometer for measuring knee JPS were assessed. Biomechanics laboratory. 10 athletes (5 men and 5 women; 26.2 ± 1.3 y, 71.7 ± 12.4 kg; 1.75 ± 0.09 m; 23.5 ± 3.9 kg/m2). Knee JPS was measured in a CKC. Absolute angular error (AAE) of knee JPS in a CKC. Intraclass correlation coefficient (ICC) and standard error of the mean (SEM) were calculated to determine the validity and reliability of the inclinometer. Data showed that the inclinometer had a high level of validity compared with an isokinetic dynamometer (ICC = 1.0, SEM = 1.39, p < 0.001), and there was very good intra- and inter-tester reliability for reading the inclinometer (ICC = 1.0, SEM = 0.85, p < 0.001). Compared with AutoCAD video analysis, inclinometer validity was very high (ICC = 0.980, SEM = 3.46, p < 0.001) for measuring AAE during knee JPS in a CKC. In addition, the intertester reliability of the inclinometer for obtaining AAE was very high (ICC = .994, SEM = 1.67, p < 0.001). The inclinometer provides a valid and reliable method for assessing knee JPS in a CKC. Health and sports professionals could take advantage of this tool to monitor proprioceptive deterioration in athletes.

Three-dimensional scapular kinematics during open and closed kinetic chain movements in asymptomatic and symptomatic subjects

The combination of open kinetic chain (OKC) and closed kinetic chain (CKC) exercises is commonly recommended in shoulder rehabilitation, aiming at improving strength and sport-specific performance. This study aimed to investigate the three-dimensional (3-D) scapular kinematics and bilateral symmetry of scapular motion during dynamic OKC and CKC movements in asymptomatic and symptomatic shoulders. Fifty subjects with unilateral shoulder pain (symptomatic subjects diagnosed with subacromial impingement syndrome, n=20) or without shoulder pain during active shoulder elevation (asymptomatic subjects, n=30) participated in the study. Furthermore, 3-D scapular kinematics were recorded using an electromagnetic tracking device in the sagittal plane of shoulder elevation for both the OKC and CKC conditions performed with slings. Data for scapular kinematics and symmetry angle (SA) were analyzed at 30°, 45°, 60°, 90°, and 120° of humerothoracic elevation. Analysis of variance models and Student׳s t-test were used to make comparisons between conditions. In general, the scapula was more externally rotated, upwardly rotated and anteriorly tilted for asymptomatic shoulders, and more upwardly rotated for symptomatic shoulders during CKC shoulder elevation. Further, comparisons of SA obtained during OKC and CKC movements revealed that during CKC, scapular motion was more symmetrical for upward–downward rotation and anterior–posterior tilt in asymptomatic shoulders and for anterior–posterior tilt in symptomatic shoulders, especially above 90° humerothoracic elevation. Differences in scapular motion during the CKC condition were in a specific pattern and enhanced symmetry, which would be considered to be a position less likely to produce compression of the rotator cuff tendons for both training in asymptomatic populations and for treatment in early rehabilitation of patients, such as those who have shoulder impingement syndrome.

Effect of Hip Adduction Position on the Vastus Medialis Oblique and Vastus Lateralis During Closed Kinetic Chain Exercise in Sitting Posture

Background: Several studies have discussed diverse exercise methods considered to be useful for the selective contraction of the vastus medialis oblique (VMO) muscle for the treatment of patellofemoral pain syndrome. Some studies have reported that exercise methods, including hip adduction, in closed kinetic chain exercises are more effective in terms of the muscle activation of the VMO and the timing of the muscle’s initial contraction. We focused on isometric contraction during a closed kinetic chain exercise with hip adduction. Objects: The purpose of this study was to examine muscle activation in the VMO and the vastus lateralis (VL) and the onset time difference between their initial contractions via closed kinetic chain isometric quadriceps femoris exercises including hip adduction. Methods: In total, 36 healthy subjects adopted two hip positions during isometric contraction of the quadriceps femoris in a closed kinetic chain exercise (hip neutral and hip adduction position). Statistical analyses were conducted using a paired t-test (α=.05). Results: Isometric contraction of the quadriceps femoris in a closed kinetic chain exercise caused a greater increase in VMO muscle activity in the hip adduction position [52.68±22.21 percentage of maximal voluntary isometric contraction (%MVIC)]than the hip neutral position (43.43±19.85 %MVIC). The onset time difference (VL-VMO) decreased more in the hip adduction position (-82.14±34.2 ㎳) than the hip neutral position (73.94±2.94 ㎳). Conclusion: We recommend this exercise as a clinically useful therapeutic method for patients with patellofemoral pain syndrome due to weakening of the VMO muscle and lateral inclination of the patella.

Resistive Hamstring Quadriceps Co-contraction Training After Acl Reconstruction

Co-contraction training (CT) was shown to be an option for quadriceps strengthening after anterior cruciate ligament reconstruction (ACLR) without loading excessive stress on the healing graft PURPOSE: The aim of this study was to investigate the effects of resistive hamstring quadriceps co-contraction training on knee muscle strength recovery and knee function after ACLR. METHODS: Fifty two patients (age: 27.5±7.6 years, body mass index: 24.9±3.7 kg/m2) who had ACLR with hamstring tendon autograft were randomly allocated into one of three trainings: 1) CT in open kinetic chain (OKC) with standard rehabilitation, 2) CT in closed kinetic chain (CKC) with standard rehabilitation and 3) only standard rehabilitation. Patients attended a baseline strength assessment for involved and uninvolved limb at 4 weeks after surgery, followed by an 8-week intervention, and they were reassessed at the end of the intervention and 12 weeks after the intervention. Knee physical functions were assessed by one leg hop distance test (OLHT) and IKDC score at 24 weeks after surgery. Repeated measures of ANOVA was used for statistical analysis RESULTS: In involved limb, time by group interaction was found significant for quadriceps strength (F(4,98)= 2.75, p=0.03) but it was not significant for hamstring strength (F(4,98)= 1.01, p=0.40), quadriceps index (F(4,98)= 0.94, p=0.47) and hamstring index (F(4,98)= 1.16, p=0.33). Quadriceps strength in Group 1 and Group 2 was found greater than control group after intervention (p=0.003, p=0.04, respectively). However, only Group 1’s quadriceps strength was greater than control group at 24 weeks after ACLR (p=0.03). IKDC score was found greater in Group 1 when compared to the control group (p=0.02) but OLHT score were not different among groups (p>0.05). CONCLUSION: The resistive hamstrings quadriceps CT in either CKC or OKC during early period of ACLR rehabilitation could be an option for the quadriceps muscle strengthening and improving knee physical function. However, this training might not be effective for hamstring strength recovery.