Yeong-Fwu Lin

Investigation of Clinical Effects of High- and Low-Resistance Training for Patients With Knee Osteoarthritis: A Randomized Controlled Trial

Background and Purpose: Muscle strength training is important for people with knee osteoarthritis (OA). High-resistance exercise has been demonstrated to be more beneficial than low-resistance exercise for young subjects. The purpose of this study was to compare the effects of high- and low-resistance strength training in elderly subjects with knee OA. Subjects and Methods: One hundred two subjects were randomly assigned to groups that received 8 weeks of high-resistance exercise (HR group), 8 weeks of low-resistance exercise (LR group), or no exercise (control group). Pain, function, walking time, and muscle torque were examined before and after intervention. Results: Significant improvement for all measures was observed in both exercise groups. There was no significant difference in any measures between HR and LR groups. However, based on effect size between exercise and control groups, the HR group improved more than the LR group. Discussion and Conclusion: Both high- and low-resistance strength training significantly improved clinical effects in this study. The effects of high-resistance strength training appear to be larger than those of low-resistance strength training for people with mild to moderate knee OA, although the differences between the HR and LR groups were not statistically significant.

Effects of weight-bearing versus nonweight-bearing exercise on function, walking speed, and position sense in participants with knee osteoarthritis: a randomized controlled trial

OBJECTIVE To investigate whether weight-bearing (WB) exercise enhances functional capacity to a greater extent than nonweight-bearing (NWB) exercise in participants with knee osteoarthritis. DESIGN Randomized controlled trial. SETTING Kinesiology laboratory. PARTICIPANTS Participants (N=106) were randomly assigned to WB exercise, NWB exercise, or a control group (no exercise). INTERVENTION WB exercise and NWB exercise groups underwent an 8-week knee extension-flexion exercise program. MAIN OUTCOME MEASURES Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function scale, walking speed, muscle torque, and knee reposition error were assessed before and after intervention. RESULTS Equally significant improvements were apparent for all outcomes after WB exercise and NWB exercise, except for reposition error, for which improvement was greater in the WB exercise group. In contrast, there were no improvements in the control group. CONCLUSIONS Simple knee flexion and extension exercises (WB and NWB) performed over 8 weeks resulted in significant improvement in the WOMAC function scale and knee strength compared with the control group. NWB exercise alone may be sufficient enough to improve function and muscle strength. The additional benefit of WB exercise was improved position sense, which may enhance complex walking tasks (walking on figure of 8 route and spongy surface).

Efficacy of 2 Non-Weight-Bearing Interventions, Proprioception Training Versus Strength Training, for Patients With Knee Osteoarthritis: A Randomized Clinical Trial

STUDY DESIGN Randomized clinical trial. OBJECTIVE To investigate the clinical and functional efficacy of 2 different non-weight-bearing exercise regimens, proprioceptive training (PrT) versus strength training (ST), for patients with knee osteoarthritis (OA). BACKGROUND Both strength and proprioceptive training are important interventions for individuals with knee OA. The benefits of weight-bearing exercises are generally recognized in the clinical setting. However, exercising in a standing or weight-bearing position may aggravate symptoms in patients with knee OA. METHODS AND MEASURES One hundred eight patients were randomly assigned to the PrT, ST, or no exercise (control) group for an 8-week intervention. Both the PrT and ST interventions consisted of non-weight-bearing exercises. Western Ontario and McMaster Universities Osteoarthritis Index-pain (WOMAC-pain) and -function scores, walking time on 3 different terrains, knee strength, and absolute knee reposition error were assessed before and after intervention. Data were analyzed using mixed-model ANOVAs. RESULTS Both PrT and ST significantly improved WOMAC-pain and -function score after intervention (P<.008). The improvement secondary to ST in the WOMAC-function scores (17.2 points) and for knee extension strength (10.3-14.9 Nm) was greater than the minimally clinically important difference for these measurements. The PrT group demonstrated greater improvement in walking time on a spongy surface and knee reposition error than the other 2 groups. No improvements were apparent in the control group. CONCLUSION Both types of non-weight-bearing exercises (PrT and ST) significantly improved outcomes in this study. PrT led to greater improvements in proprioceptive function, while ST resulted in a greater increase in knee extensor muscle strength.

Comparison of proprioceptive functions between computerized proprioception facilitation exercise and closed kinetic chain exercise in patients with knee osteoarthritis

AimThe aim of this study was to compare proprioceptive function between computerized proprioception facilitation exercise (CPFE) and closed kinetic chain exercise (CKCE) for knee osteoarthritis.DesignRandomized–controlled.SettingKinesiology laboratory.PatientsEighty-one patients with bilateral knee osteoarthritis were randomly assigned to CPFE, CKCE, and control groups.InterventionBoth exercise groups underwent an 8-week program of three sessions per week. The control group received no training. The CPFE program included a 20-min computer game to be played by the trained foot of the subject. CKCE included 10 sets of 10 repetitions of repeated knee extension and flexion with resistance of 10–25% of body weight.Main outcome measuresAbsolute reposition error, functional score, walking speed, and knee muscle strength were assessed with an electrogoniometer, the physical function subscale of Western Ontario and McMaster Osteoarthritis Index, a CASIO stopwatch, and a Cybex 6000 dynamometer before and after the 8-week period.ResultsThe results of this study showed that both CPFE and CKCE were effective in improving joint position sense, functional score, walking speed, and muscle strength. Furthermore, CKCE showed greater effect in increasing knee extensor torque in patients with knee osteoarthritis.ConclusionClinical effects of CPFE were the same as those of CKCE except for knee extensor torque. The increase in knee extensor torque in CPFE patients was not as great as that seen in CKCE patients.

Role of the Vastus Medialis Obliquus in Repositioning the Patella: A Dynamic Computed Tomography Study

Background It has been assumed that patellofemoral pain syndrome results from patellar malalignment. The precise role the vastus medialis obliquus plays in mediating the underlying pathologic abnormality is unclear. Hypothesis The morphologic characteristics of the vastus medialis obliquus correlate to patellar malalignment in patients with patellofemoral pain syndrome. Study Design Cross-sectional study; Level of evidence, 3. Methods One hundred twelve patients with patellofemoral pain syndrome were studied. Six sets of computed tomography axial images were assessed in which knee flexion was 0°, 15°, or 30° and the quadriceps muscle either relaxed or contracted. Measurements of serial cross-sectional areas of the vastus medialis obliquus and patellar malalignment were made. Correlation and stepwise regression models between the vastus medialis obliquus variables and patellar malalignment (lateral shift and patellar tilt) were calculated. Statistics were calculated on 4 subgroups depending on patellofemoral malalignment type. Results Significant correlations were found between measures of cross-sectional areas of vastus medialis obliquus and patellar tilt at 0° and 30° of knee flexion. Using a regression model, it was determined that vastus medialis obliquus is predictive of patellar tilt (R 2 = 0.078–0.130). This explanation was most apparent in the subgroup of patients with extreme patellar tilt and lateral shift malalignments (R 2 up to 0.824). Conclusion There are significant correlations between vastus medialis obliquus variables and patellar malalignments in extended knees of patients with patellofemoral pain syndrome. Clinical Relevance Vastus medialis obliquus muscle function is important to consider in the rehabilitation of patients with patellofemoral pain syndrome, especially those with extreme patellar tilt and lateral shift malalignments.

Differences in Sonographic Characteristics of the Vastus Medialis Obliquus Between Patients With Patellofemoral Pain Syndrome and Healthy Adults

Background There is controversy regarding the relationship between patellofemoral pain syndrome (PFPS) and insufficiency of the vastus medialis obliquus (VMO). The conventional clinical practice of VMO strengthening for PFPS has been challenged for lack of evidence. The purpose of this study was to observe the difference in sonographic findings of the VMO between patients with PFPS and healthy adults. Hypothesis The morphological characteristics of the VMO are different between patients with PFPS and healthy adults. Study Design Case-control study; Level of evidence, 3. Methods Fifty-four patients with PFPS and 54 age-, gender-, body height—, and body weight—matched healthy adults as controls were enrolled in the study to measure by sonography the insertion level, fiber angle, and volume of the VMO at its insertional portion to detect differences between patients with PFPS and healthy controls. Results The insertion level, fiber angle, and VMO volume were all significantly smaller in the PFPS group than in the control group (P < .05). Multivariate analysis of variance has revealed a Wilks λ value of .845 and an F value of 5.640 (P = .001). Conclusion There was a significant difference in the 3 VMO measures between patients with PFPS and the healthy controls. Individuals might be predisposed to PFPS by different VMO characteristics, including insertion level and fiber angle. The current study cannot determine whether the observed morphological differences were the results of atrophy in response to pain or if they represent dysplasia that was predisposed to pain development. The clinical manifestations of VMO characteristics should be thoroughly investigated in other populations. Clinical Relevance The function of the VMO is important to consider in the rehabilitation of patients with PFPS.

Surplus Value of Hip Adduction in Leg-Press Exercise in Patients With Patellofemoral Pain Syndrome: A Randomized Controlled Trial

Background: A common treatment for patients with patellofemoral pain syndrome (PFPS) is strength (force-generating capacity) training of the vastus medialis oblique muscle (VMO). Hip adduction in conjunction with knee extension is commonly used in clinical practice; however, evidence supporting the efficacy of this exercise is lacking. Objective: The objective of this study was to determine the surplus effect of hip adduction on the VMO. Design: This study was a randomized controlled trial. Setting: The study was conducted in a kinesiology laboratory. Participants: Eighty-nine patients with PFPS participated. Intervention: Participants were randomly assigned to 1 of 3 groups: hip adduction combined with leg-press exercise (LPHA group), leg-press exercise only (LP group), or no exercise (control group). Training consisted of 3 weekly sessions for 8 weeks. Measurements: Ratings of worst pain as measured with a 100-mm visual analog scale (VAS-W), Lysholm scale scores, and measurements of VMO morphology (including cross-sectional area [CSA] and volume) were obtained before and after the intervention. Results: Significant improvements in VAS-W ratings, Lysholm scale scores, and VMO CSA and volume were observed after the intervention in both exercise groups, but not in the control group. Significantly greater improvements for VAS-W ratings, Lysholm scale scores, and VMO volume were apparent in the LP group compared with the control group. There were no differences between the LP and LPHA groups for any measures. Limitations: Only the VMO was examined by ultrasonography. The resistance level for hip adduction and the length of intervention period may have been inadequate to induce a training effect. Conclusions: Similar changes in pain reduction, functional improvement, and VMO hypertrophy were observed in both exercise groups. Incorporating hip adduction with leg-press exercise had no impact on outcome in patients with PFPS.

Association Between Sonographic Morphology of Vastus Medialis Obliquus and Patellar Alignment in Patients With Patellofemoral Pain Syndrome

STUDY DESIGN Descriptive, correlational, anatomical laboratory study. OBJECTIVES To investigate the association between the morphology of the vastus medialis obliquus (VMO) and patellar alignment in patients with patellofemoral pain syndrome (PFPS). BACKGROUND It has long been presumed that PFPS results from patellar malalignment. Strengthening of the VMO has been suggested as an intervention to treat individuals with PFPS, through correction of abnormal patellar tracking. However, the exact role of the VMO in the etiology and treatment of PFPS is not clear. METHODS AND MEASURES This study included 58 patients with PFPS, of which 31 had bilateral involvement. A total of 89 knees were imaged with a Merchants view radiograph at 45 degrees of knee flexion to measure patellar alignment consisting of patellar tilt and congruence angles. Those 89 knees were also examined with sonography with the knee in full extension and quadriceps relaxed to measure VMO morphology and additional characteristics such as insertion level, insertion ratio, fiber angle, and volume. The level of association between radiographic and sonographic measurements was explored to determine any relationship between patellar alignment and morphology of the VMO. RESULTS The patellar tilt angle was negatively correlated with the VMO insertion level (r = -.58, P<.05), insertion ratio (r= -.52, P<.05), and volume (r = -.45, P<.05). In addition, the patellar congruence angle was negatively correlated with the VMO fibers angle (r = -.23, P<.05). CONCLUSIONS This study showed that some aspects of VMO morphology, measured in full knee extension with the quadriceps relaxed, were associated with patellar alignment measured with the knee at 45 degrees of flexion. Whether or not VMO morphology serves as a predictor of patella alignment with the knee extended should be the focus of future investigations.

Scapular kinematics and impairment features for classifying patients with subacromial impingement syndrome

Subacromial impingement syndrome (SAIS), which is associated with pain and a loss of function, has a high occurrence in the physically active population. Not all patients respond positively to treatment. Classifying patients can improve decision-making. The scapular kinematic and clinical impairments can aid in classifying the patients who are more likely to respond to physical therapy treatment. Thirty-three subjects (males, 20-33 years) presenting SAIS were studied to determine altered scapular kinematics and clinical impairments. Three measurements were collected: (1) three-dimensional scapular kinematics during performing functional tasks; (2) impairment outcomes of range of motion and muscle force; and (3) self-reported measurements of pain, satisfaction, and function. All patients received 6-week (2 times per week) physical therapy treatment. Improvement with treatment was determined using the Global Rating of Change Scale. Scapular kinematics and clinical impairments were first identified by t-test in predicting improvement and then combined into a multivariate prediction method. A prediction method with three variables (Flexilevel Scale of Shoulder Function score < 41, muscle power of serratus anterior < 27.4% body weight, degree of scapular internal rotation at 30° shoulder elevation during descending arm phase in unloaded condition<0.7°) were identified. It appears that scapular kinematics and impairment features can be used to classify subjects with SAIS in addition to self-report. Prospective validation of the proposed prediction method requires further investigation.

Proprioception assessment in subjects with idiopathic loss of shoulder range of motion: joint position sense and a novel proprioceptive feedback index.

We examined the effects of elevation range and plane on shoulder joint proprioception in subjects with idiopathic loss of shoulder range of motion (ROM). Joint position sense (JPS) and a novel proprioceptive feedback index (PFI), including difference magnitude and the similarity index, were used to assess proprioception. Twelve subjects (eight male, four female) with involved stiff shoulders and normal opposite shoulders were recruited from a university hospital. Subjects attempted to repeat six target positions. Target positions consisted of arm elevation in three planes (frontal, scapular, and sagittal planes) and two ranges (end/mid range). Six trials of each target position were used to determine acceptable trials for stabilization of the data, less than 5% of the cumulative mean values for at least three successive trials. The data stabilized at the sixth repetition. Compared to control shoulders, involved shoulders had enhanced proprioception during end range movements (p < 0.05). The magnitude of the repositioning error and difference magnitude decreased (1.6°–3.5° for repositioning error and 22.2°–62.1° for difference magnitude), whereas similarity index improved at end range movements compared to mid range movements (p < 0.05) in involved stiff shoulders. Results of JPS and PFI suggest that both capsuloligamentous and musculotendinous mechanoreceptors play an important role in proprioception feedback during active movements in subjects with idiopathic loss of shoulder ROM.