Proprioceptive capacity of the knee joint area in patients after rupture of the anterior cruciate ligament]

In 30 healthy volunteers with clinically inconspicuous knee joints the proprioception of the knee joint was evaluated by an angle reproduction test. With the same set-up we documented the effect of an elastic knee bandage. We could not document any differences between the left and the right knee joint or between men and women, but at the mid-range of motion, proprioception was worse compared to the end range of motion. The applied elastic knee bandage significantly improved the position sense. Additionally 25 patients with an isolated rupture of the anterior cruciate ligament were evaluated. Fourteen patients were examined preoperatively 11 after operative ACL reconstruction. Preoperatively proprioception was significantly poorer than in the control group. We were able to show a positive influence of a knee bandage on the proprioception of the injured knee as well. Patients after ACL reconstruction showed no significantly better proprioception than the preoperative group.     

Proprioceptive deficits of the knee joint after rupture of the medial meniscus

We assessed knee joint proprioception in 23 patients with an isolated lesion of the medial meniscus. Thirteen patients were tested prior to their arthroscopic operation, and 10 patients were examined after partial arthroscopic resection of the injured meniscus. As a control group we evaluated 30 healthy volunteers with clinically inconspicious knee joints. For documentation of the proprioceptive capabilities we performed an angle reproduction test. Additionally the subjects were tested with and without an elastic knee bandage, to test the influence of such a bandage on knee joint proprioception. Our results showed that preoperatively proprioception was significantly less good than in the control group. We found no influence of the knee bandage on the proprioception of the injured knee. The postoperative group of patients showed significantly better proprioceptive capability than the preoperative patients. The postoperative results did not differ significantly from those of the control group.     

Knee joint proprioception in normal volunteers and patients with anterior cruciate ligament tears, taking special account of the effect of a knee bandage

Proprioception of the knee joint was tested in 30 healthy volunteers with clinically inconspicuous knee joints. To examine proprioception, an angle reproduction test was performed. We could not document any differences between the left and the right knee joint or between men and women. At the mid-range, proprioception was worse compared with the end range of motion. In addition, 25 patients with an isolated rupture of the anterior cruciate ligament were evaluated, 14 before and 11 after operative anterior cruciate ligament (ACL) reconstruction. Preoperatively, there was a significant deterioration of proprioception compared with the control group. We were able to show a positive influence of a knee bandage on the proprioception of the injured knee. Patients after ACL reconstruction showed no significantly better proprioception compared with the preoperative group.     

The effect of intraarticular anesthesia and elastic bandage on elbow proprioception

Twenty uninjured male volunteers were studied to characterize normal elbow proprioception and to investigate the effect of applying an elastic bandage to the extremity and injection of an intraarticular anesthetic. A modified Biodex dynamometer was used to study position sense and detection of motion. In part 1 of the study position sense was tested by flexing the elbow to a predetermined angle, returning to the starting position, and then asking the subject to identify that angle. In part 2 detection of motion was tested by asking the subject to disengage the apparatus by pressing a stop button when movement was detected. The testing conditions in part 1 and part 2 were repeated after the elbow was wrapped with an elastic bandage and again after an intraarticular injection of 3 cc 1% lidocaine with the bandage removed. Ten additional subjects underwent testing of both elbows to examine the effect of arm dominance. Mean position sense was within 3.3 degrees+/-1.3 degrees of the actual angle in trials without an elastic bandage or an anesthetic. A significant improvement in position sense was observed (2.2 degrees+/-1.2 degrees) after an elastic bandage was applied (P < .004). No significant difference was seen in position sense after lidocaine was injected. The mean threshold for detection of motion in trials without an elastic bandage or an anesthetic was 4.21 degrees+/-1.56 degrees. No significant differences were seen in detection of motion observed with the elastic bandage or intraarticular anesthetic. No significant differences were seen between dominant and nondominant extremities for both position sense and detection of motion. The application of an elastic bandage improved position sense, suggesting that tactile cues from cutaneous or other extraarticular receptors may play a role in elbow proprioception. Intraarticular anesthesia, however, had little effect, suggesting that intracapsular receptors play a lesser role in elbow proprioception. The determination of proprioceptive qualities for the normal elbow can aid in the understanding of elbow function and provide a basis for defining its role in elbow dysfunction.     

Effect of gut transposition on the expression of the endocrine gene neurotensin

PURPOSE: The purpose of this study was to evaluate joint position sense (JPS) in patients with posttraumatic glenohumeral instability. MATERIALS AND METHODS: In 28 patients with posttraumatic instability and in a matched control group of 30 subjects proprioception capability was evaluated. For documentation of proprioception an angle reproduction test (ART) was performed with which joint positions sense (JPS) was measured for abduction, flexion, and rotation in three angles each. RESULTS: In both groups there was a significant better JPS with visual control than without. In contrast to the control group the patients were not able to increase angle reproduction capability without visual control when comparing positions below shoulder level with positions at or above shoulder level. When comparing the patients to the controls there were differences in most of the ARTs with worse results in the patient group. These differences were significant in 150 degrees flexion with and without visual control, in 150 degrees abduction without and in 100 degrees abduction with visual control. For rotation there were trends for almost all joint positions, however, the differences were significant only in the -45 position. When comparing the noninjured contralateral shoulder of the patients with the control group, there still were differences. Again these were not in all joint positions significant, but significant worse JPS could be demonstrated in 150 degrees abduction without visual control, 50 degrees flexion without visual control, -45 degrees rotation without and 0 degrees rotation with visual control. CONCLUSIONS: A proprioceptive deficit can be documented in patients with posttraumatic glenohumeral instability. This may be one reason for permanent instability. The contralateral joint also shows reduction in joint position sense. For consecutive treatment as well as for rehabilitation both shoulder joint should be addressed.     

The structure of the common atrioventricular valve in hearts having isomeric atrial appendages and double inlet ventricle

The primary purpose of the study was to examine the role of the posterior cruciate ligament (PCL) in knee-joint proprioception after total knee arthroplasty (TKA). Knee-joint proprioception was measured in 10 patients with nonsacrificed PCL TKAs and 10 with sacrificed PCL TKAs. Knee-joint proprioception was evaluated through reproduction of static knee angles using a Penny and Giles electrogoniometer. The primary variable was absolute angular error (AAE). AAE was defined as the absolute value of the difference between the test angle and the patient's perceived version of the test angle. Proprioception deficit was compared to the WOMAC questionnaire which evaluates pain, stiffness, and physical function of the lower extremity. No significant difference was found between the nonsacrificed PCL TKA (4.33 degrees +/- 1.52 degrees) and sacrificed PCL TKA (4.38 degrees +/- 1.39 degrees) AAE values (P > .4). Furthermore, no significant differences were observed in the WOMAC questionnaire scores for all three parameters between the two types of knee prosthesis (P > .35). The current findings suggest that the preservation of the PCL in TKA may not improve knee-joint proprioception and subsequently may not improve TKA functional performance.     

Improvements in quadriceps sensorimotor function and disability of patients with knee osteoarthritis following a clinically practicable exercise regime

OBJECTIVE: Quadriceps sensorimotor dysfunction may be important in the pathogenesis of knee osteoarthritis (OA) and a determinant of disability. Exercise regimes can increase quadriceps strength, but whether this improves proprioception and reduces disability is uncertain. Moreover, research regimes involve protracted treatment which is clinically impracticable. METHODS: We compared quadriceps sensorimotor function and disability in 60 patients with knee OA, before and after an exercise regime, with a control group (n = 37) who did not exercise. RESULTS: Exercise improved quadriceps strength (mean change, 95% CI; 73 N, 26-19 N), voluntary activation (14%, 5-20%), knee joint position sense (0.6 degrees, 0.1-1.8 degrees), and reduced the Lequesne Index (3.5, 0.5-4) and aggregate time of four activities of daily living (8.4 s, 0.2-16.7 s). At 6 month follow-up, these improvements were maintained. The parameters of the control group were unchanged. CONCLUSIONS: These results substantiate the association between quadriceps sensorimotor dysfunction and disability, emphasizing the importance of quadriceps exercise in the management of knee OA. The regimen is relatively brief and clinically practicable, but could be adapted to make it more cost effective.     

Is knee joint proprioception worse in the arthritic knee versus the unaffected knee in unilateral knee osteoarthritis?

OBJECTIVE: Neuromuscular joint protection requires proprioceptive input and motor output. Impairment of proprioception in knee osteoarthritis (OA) may contribute to, and/or result from, the disease. If this impairment was exclusively a local result of OA, a between-knee difference would be expected in patients with unilateral OA (UOA). To explore causal directions, 2 hypotheses were tested: 1) proprioception is worse in UOA patients versus elderly controls; 2) proprioception is worse in the arthritic knee versus the unaffected knee in UOA patients. METHODS: Twenty-eight UOA patients (Kellgren-Lawrence grade > or =2 in 1 knee and <2 in the other knee) and 29 elderly controls were enrolled. The unaffected knee of each UOA patient and both knees of the elderly controls were required to meet symptom, examination, and radiographic criteria. Proprioception (detection threshold of joint displacement after slow, passive, automated knee motion), body mass index, pain, functional status, range of motion, and laxity were measured. RESULTS: UOA patients had worse proprioception than did elderly controls, in either knee. A between-knee difference was not found in UOA patients. CONCLUSION: Impaired proprioception is not exclusively a local result of disease in knee OA. The relative importance of impaired proprioception in the development and progression of knee OA will require longitudinal study.     

Torque/velocity properties of human knee muscles: peak and angle-specific estimates

Angle-specific (AS) torque/velocity data have been used to avoid angle related variation in peak torque capacity. However, series elastic structures cause the contractile velocity of active force-producing tissue to differ from external joint velocity except at peak torque. Alternatively, angle related variation may be removed by normalizing peak torque to the isometric maximum at that angular position. The AS, peak (P), and normalized peak (NP) methods were compared in isovelocity knee flexion and extension at velocities between 50 and 250 degrees s-1 for 8 male subjects. The P and NP methods gave more similar torque/velocity relations than the AS method. Further, very little variation in peak torque was attributed to differences in joint angle. Both the P and AS methods illustrate that relative quadriceps/hamstrings torque capability (flexor/extensor ratio) increases slightly with velocity. It is proposed that antagonist muscle torque capabilities should be compared at different angular positions to assess muscular imbalance.     

Effect of a neoprene sleeve on knee joint position sense during sitting open kinetic chain and supine closed kinetic chain tests

The primary objective of the present study was to compare the effect of a neoprene sleeve on knee joint position sense during a sitting open kinetic chain test and a supine closed kinetic chain test. Young (24 +/- 2 years old), healthy subjects (18 men and 18 women) performed knee joint angle replication tests during open kinetic chain knee extension (sitting) and closed kinetic chain leg press (supine with an axial load of 15% body weight) before and after application of a neoprene sleeve over the dominant knee. The improvement in ability to replicate joint angles after application of the sleeve (sleeve effect) was significantly less during the supine closed kinetic chain test (0.3 degree +/- 1.4 degrees) than during the sitting open kinetic chain test (1.2 degrees +/- 1.1 degrees). The sleeve effect was inversely related to subjects' performance without the sleeve during both the sitting open kinetic chain and supine closed kinetic chain tests, suggesting that some people may derive greater benefit from the sleeve than others. Although the sleeve effects were small, particularly during the supine closed kinetic chain test, 72% of subjects felt that the sleeve improved their overall test performance. Future research is needed to establish the functional relevance of the small sleeve effects observed and to identify the characteristics of people who might derive greatest benefit from sleeve use.     

Ankle, knee, and hip moments during standing with and without joint contractures: simulation study for functional electrical stimulation

Joint contractures have been one of the contraindications for use of functional electrical stimulation for standing in paraplegic patients. A simulation study using a three-segment link mechanical model of the human body was performed to calculate the muscle moments at the ankles, knees, and hips during standing with and without having joint contractures. The knee and hip angles were varied in 5 degrees increments, whereas the ankle angles were varied in 1 degree increments. It was assumed that energy efficient posture was obtained with the least sum of the squared moments of the ankles, knees, and hips joints by the muscles. Ankles at 5 degrees of dorsiflexion, knees at 0 degrees, and hips at 15 degrees of extension resulted in the most energy efficient posture without joint contractures. The muscle moments increased with the increase in angle of contractures. The joint contractures at ankle angles > or = 6 degrees of plantar flexion, knee angles > or = 20 degrees of flexion, and/or hip angles > or = 20 degrees of flexion produce a potentially unstable posture. These findings suggest that some degree of joint contractures can be tolerated in paraplegic patients using functional electrical stimulation for standing.     

Knee joint effusion and proprioception

The purpose of this study was to examine the effects of excessive fluid in the knee joint on proprioception. Twenty healthy subjects with no knee pathology participated in this study. Subjects were randomly assigned to control and experimental groups. Baseline measurements of subjects performing a tracking task were then recorded. Specifically, one knee joint was moved passively by a dynamometer through a range of motion from approximately 90 degrees flexion to 10 degrees from full extension at a joint angular velocity of 60 degrees/sec. Subjects were blindfolded and required to track the passively moving joint as accurately as possible for a period of 1.25 minutes with the opposite limb. An electrogoniometer was used to monitor the motion of the active tracking limb. Ninety mL of a solution of saline and dextrose were injected into the knee joint cavity of the experimental subjects, and they repeated the tracking task. After a 5-minute rest, the control group subjects also repeated the task. The results indicated that the injection of fluid did not change the subjects' error in tracking the passively moving limb (p > 0.05). No change in the error associated with tracking was observed for the control group (p > 0.05). It is suggested that the effects of long-term effusions and the nature of the inflammatory fluid might be more responsible for the loss of proprioception observed in some clinical conditions.     

Prediction of postoperative knee flexion in Insall-Burstein II total knee arthroplasty

Postoperative knee flexion in patients undergoing Insall-Burstein-II total knee arthroplasty at 2 years was evaluated regarding two basic questions: what groups of patients gain or lose the most flexion and what groups of patients have the best or worst postoperative flexion. Thirteen preoperative variables (maximum flexion, flexion arc, tibiofemoral angle, quadriceps strength, extensor lag, Knee Society score, Knee Society patient assessment, gender, age, height, weight, diagnosis, and surgeon) and four postoperative variable (leg length change, tibiofemoral angle, distance from patella to the joint line, and the tibial prosthesis anteroposterior translation on a lateral radiograph) were used in an attempt to explain postoperative flexion. The analysis was performed on 164 consecutive Insall-Burstein-II total knees in which the data were gathered prospectively on a time oriented medical record database. A regression tree analysis was used to identify several groups of patients, characterized by preoperative factor values, who had markedly above average performance on postoperative flexion. The preoperative factors identified include preoperative flexion, flexion arc, tibiofemoral angle, extensor lag, diagnosis, and age. The only postoperative variable of significance was tibiofemoral angle. Among the potential determinants of postoperative flexion that failed to appear predictive were the Knee Society scores and surgeon. Preoperative flexion is known to be a critical determinant of postoperative flexion in total knee replacement. However, in the current study, preoperative flexion accounted for only half of the difference between the best (122 degrees) and the worst (88 degrees) group, as determined with regression tree analysis.     

In vitro laxity-testers for knee joints of mice

The knee joints of mice can be used as a model for studying the effects of interventions on knee laxity. The goal of this study was to quantify knee joint laxity in vitro. Three devices were developed: a positioning- and cementing device, an anterior-posterior (AP) laxity tester and a varus-valgus (VV) laxity tester. The positioning and cementing device was used to position the joint in a reproducible way and to attach clamping pins to the proximal femur and distal tibia using PM MA. The clamping pins were used to fix the joint to the AP- and VV-testers. In both testers the load was applied by means of a spindle-actuated spring while load and displacements were measured simultaneously. The load--displacement data were used to calculate displacement and compliance parameters. The performance of the testers was evaluated by testing 5 normal knee joints of 5 mice. Total AP-translation at + or - 0.8 N was 0.43 (+ or - 0.16 S.D.) mm with compliances of 0.14 (+ or - 0.05 S.D.) mm N(1) and 0.12 ( + or - 10.05 S.D.) mm N(-1) at 0.8 N posterior and anterior force, respectively. Total VV-rotation at + or - 4 Nmm was 17.2 (+ or - 2.6 S.D.) degrees with compliances of 0.9 degrees Nmm(-1) (+ or - 0.2 degrees Nmm(-1) S.D.) and 1.0 Nmm(-1) (+ or - 0.4 degrees Nmm(-1) S.D.) at 4 Nmm valgus and varus moment, respectively. The contributions of the deformations of the bones and the fixtures to the rotations were negligible in the VV-test. In the AP-test they account for approximately 0.07 ( + or - 0.03 S.D.)mm of the total AP-translation. This will not affect the utilization of the device for comparative analysis. It is concluded that in in vitro evaluation of AP- and VV-laxity in knees of mice is feasible with sufficient accuracy for evaluation of changes after ligament damage.     

Selective ablation of rat knee joint innervation with injected immunotoxin: a potential new model for the study of neuropathic arthritis

Neuropathic arthropathy is a severe chronic degenerative condition associated with decreased or absent sensory innervation of the involved joint. Existing animal models of neuropathic arthritis are limited by the technical difficulties of obtaining either highly selective or complete joint denervation in a minimally invasive fashion. We undertook experiments to determine the feasibility of using the newly described method of selective neuronal lesioning with injected immunotoxin as a means of creating a more tractable model of neuropathic arthritis. Retrograde tracing with fluorochrome revealed that the knee joint of the female Wistar rat is supplied by 581 +/- 31 (mean +/- SD) joint afferents. Immunohistochemistry confirmed that virtually all sensory neurons in the rat express the cell surface receptor Thy 1. Injection of rat knee joints with an immunotoxin targeted toward Thy 1 resulted in the selective ablation of an average of 88% of the joint afferents identified with fluorochrome that are normally found in the ipsilateral L3 and L4 ganglia.     

The patellar tilt angle: correlation of MRI evaluation with anterior knee pain

The purpose of this study was to analyze the degree of patella tilt and its correlation with the symptoms of anterior knee pain. We used magnetic resonance imaging (MRI) to measure the angle of patella tilt. The patients (n = 128) were classified into two groups. Group 1 (n = 78) included patients who had never had symptoms of anterior knee pain but had MRI for evaluation of the menisci and the ligaments. Group 2 (n = 50) included patients who had MRI for evaluation of anterior knee pain syndrome. Patients who had gross deformities like patellar dislocation, tricompartmental osteoarthritis, or inflammatory arthritis were excluded. The average patella tilt angle was 6.3 (SD = 3.9) and 12.8 (SD = 8.4) degrees, respectively, for the two groups of patients. Twenty-three patients in group 2 underwent arthroscopy because of failure of conservative treatment, and the average patella tilt angle in this subgroup was 16.4 degrees. Our study suggests that patella tilt angle is correlated with the symptoms of anterior knee pain, and indicated that the cause of pain came from the tight lateral retinaculum. In addition, MRI was found to be an accurate and reproducible method of measurement of the patellar tilt angle.     

Total knee replacement after failed tibial osteotomy: results of a matched-pair study

Sixty-three total knee replacements were performed after a failed tibial osteotomy. The goal of this study was to compare the perioperative problems and the outcome of this group of patients (study group) to a group of patients with primary arthroplasties matched for age, gender, length of follow-up, weight, and preoperative Charnley class. Operative problems were more frequently encountered in the study group, with 7 tibial tubercle elevations and 15 lateral retinaculum releases needed, whereas lateral retinaculum release was necessary for only 1 knee in the control group. Outcome was assessed using both the International Knee Society (IKS) scoring system and Hospital for Special Surgery (HSS) knee score. The follow-up period averaged 4.6 years. The IKS score of the control group was significantly higher, averaging 80.9 +/- 13.8, whereas it was 74.4 +/- 14.8 for the study group (P = .0001). Among the parameters included in the knee score, only pain was significantly different with the control group (P = .03). The IKS function score and the HSS score were not statistically different. Conversion of a failed tibial osteotomy is a technically demanding procedure. Careful preoperative planning is needed. Results, especially on pain, appeared to be inferior to those for primary arthroplasties.     

Effect of coordination training on proprioception of the functionally unstable ankle

Exercises to improve joint proprioception and coordination of the functionally unstable ankle are advocated throughout the literature, yet there is little evidence that these exercise have any effect on proprioception and balance. The purpose of this study was to determine the effects of a 6-week coordination and balance training program on proprioception of subjects with functional ankle instability. Forty-five subjects (age = 22.53 +/- 3.95 years, height = 172.04 +/- 10.0 cm, weight = 71.72 +/- 15.7 kg) were randomly placed into a control (Group 1), sham (Group 2), or experimental (Group 3) group. The experimental group trained 3 days per week, 10 minutes each day, performing various balance and proprioception exercises. Postural sway and active and passive joint position sense were assessed. Analysis of variance for postural sway modified equilibrium score for anterior and posterior sway, as well as medial and lateral sway revealed significant four-way interactions. Tukey post hoc analyses revealed that Group 3 performed significantly better (p < .05) than Group 1 and Group 2 on the posttests. There were no significant differences for joint position sense or postural sway index. Results suggest that balance and coordination training can improve some measures of postural sway. It is still unclear if joint position sense can be improved in the functionally unstable ankle.     

The derivation of knee joint types from the geometry of the cruciate ligament four-bar system

The system of the anterior (a) and posterior (p) cruciate ligaments and their distances between attachments to femur (f) and tibia (t) as found in the knee joint of tetrapods is considered as a planar crossed four-bar linkage. The shape of the femoral articulating surfaces (condyles) can be calculated starting from a flat or curved tibial articulating surface and known bar-lengths (Menschik, 1974 Z. Orthop. 112, 481-495; Huson 1974 Orthop?de 3, 119-126). Regression analysis of the dimensions of the cruciate ligament four-bar system of 11 species of mammal and one species of bird revealed a general ratio of (a): (t): (p): (f) = (7.1): (7.9): (10.0): (6.1). These data differ from the results obtained by Badoux (1984 Acta Anat. 119, 60-64) who examined only dog and horse. Our data of the dog agree with those of Badoux, i.e. (a): (t): (p): (f) approximately equal to (10): (8): (10): (4). Based on these ratios between bar-lengths, two types of knee joint shapes were distinguished. The shape of the dog's joint ("type A") has a very large femoral condyle compared with the tibial articulating surface. Maximum knee angulation is 170-180 degrees. Sliding between the articulating surfaces of this joint is distributed approximately uniformly over the whole angulation range. The general shape obtained from the regression analysis ("type R") has a relatively small femoral condyle and an angulation range of about 174 degrees. Uniformly distributed sliding occurs with this range over an angle less than 90 degrees. Theoretically derived, limiting requirements concerning maximum angulation range (delta gamma max < or = 180 degrees), stabilization (e.g. avoidance of a perpendicular position of the cruciate ligaments to the articulating surfaces; delta gamma 78.5 max > or = 90 degrees) and uniformly distributed sliding (delta gamma s > or = 30 degrees) lead to at least two different possible knee joint shapes. These shapes correspond to the two real knee joint shapes found from the statistical analysis mentioned above. This was verified by studying quantitative characteristics obtained from the derivation of knee joint shapes from the bar lengths and vice versa. The bird (Ardea) possessed a knee joint shape, very different from the shapes described above (i.e. f > t, type D1).     

The estimation of efficacy of oral iron supplementation during treatment with epoetin beta (recombinant human erythropoietin) in patients undergoing cardiac surgery

OBJECTIVE: Quantitative evaluation of radiographic methods proposed to improve the detection of joint space narrowing (JSN) in femorotibial osteoarthritis (OA). METHODS: Thirty-two consecutive patients with knee OA and five normal controls had three different weight-bearing radiographs of the knee: (1) anteroposterior film of both knees in full extension (extended knees), (2) anteroposterior film of one knee in extension while the patient was standing on the homolateral foot (standing on homolateral foot), (3) posteroanterior film of both knees flexed at 30 degrees (schuss view). Joint space was analyzed blind using both an evaluation of JSN with a six-grade scale (JSN score) and an image analyser computer measurement of the mean joint space width (mean JSW). The medial compartment of medial femorotibial OA knees, the lateral compartment of lateral femorotibial OA knees, as well as both compartments of control knees, were measured. Extended knee and schuss views were made 1 year later in 10 patients for the evaluation of sensitivity to change. RESULTS: The JSN scores +/- S.D. in schuss, standing on the homolateral foot and extended knee views were 2.75 +/- 1.31, 1.95 +/- 1.3 and 1.66 +/- 1.27, respectively. The mean JSW +/- S.D. in schuss, standing on the homolateral foot, and extended knee views were 2.9 +/- 1.9 mm, 3.5 +/- 1.6 mm and 3.8 +/- 1.5 mm, respectively. Changes in JSN scores and mean JSW with schuss view increased with OA severity. In controls, JSW of the medial compartment did not vary in the three views. JSW of the lateral compartment of controls was significantly larger in the schuss view. The change in JSW after 1 year was -0.41 mm (P = 0.02) in the schuss view and -0.17 mm (P > 0.05) in the extended knee view. CONCLUSION: The schuss view is suggested as the most accurate method for the evaluation of JSW in femorotibial OA.