Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) and T2 mapping of talar osteochondral lesions: Indicators of clinical outcomes.

PURPOSE: To evaluate the utility of delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) and T2 mapping in evaluation of type II osteochondral lesions (OCLs) of the talus and define cutoff values for identifying patients with good/poor clinical outcomes. MATERIALS AND METHODS: 28 patients (mean age, 42.3 years) underwent T2 mapping and dGEMRIC at least 1.5 years (mean duration, 3.5 years) after microfracture (n = 12) or conservative (n = 16) treatment for type II OCL. Clinical outcomes were considered good with an American Orthopedic Foot and Ankle Society score ≥80. The T1 /T2 -values and indices of repair tissue (RT; cartilage above the OCL) were compared to those of the adjacent normal cartilage (NC) by region-of-interest analysis. The ability of the two methods to discriminate RT from NC was determined by area under the receiver operating characteristics curve (AUC) analysis. The Youden index was maximized for T1 /T2 measures for identifying cutoff values indicative of good/poor clinical outcomes. RESULTS: Repair tissue exhibited lower dGEMRIC values (629.83 vs. 738.51 msec) and higher T2 values (62.07 vs. 40.69 msec) than NC (P < 0.001). T2 mapping exhibited greater AUC than dGEMRIC (0.88 vs. 0.69; P = 0.0398). All T1 measures exhibited higher maximized Youden indices than the corresponding T2 measures. The highest maximized Youden index for T1difference was observed at a cutoff value of 84 msec (sensitivity, 78%; specificity, 83%). CONCLUSION: While T2 mapping is superior to dGEMRIC in discriminating RT, the latter better identifies good/poor clinical outcomes in patients with type II talar OCL. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2017;46:1601-1610.

Ball games and nutrition counseling improve postural control in overweight children.

BACKGROUND: Motor skills are impaired in overweight children whose levels of physical activity are low and these children are more likely to sustain lower extremity injuries. The purpose of this study was to analyze prospectively in overweight children the influence of ball games and nutrition counseling on postural control. METHODS: In all, 46 overweight children (age: 6-12 years, BMI: female: 25.2 ± 3.6 kg/m(2), male: 26.2 ± 2.8 kg/m(2) (mean value ± standard deviation) were examined prospectively in four randomized groups (ball games, nutrition counseling, ball games and nutrition counseling, and group without intervention) for six months. A one-legged standing test was performed. RESULTS: The children demonstrated improved postural control after six months of intervention: mean difference M1-M2 ± standard deviation: 5 ± 6 error points (p < 0.001, T = 4.906), whereas the control group without intervention did not show any significant improvement: 2 ± 8 error points (p = 0.357, T = 0.972). CONCLUSIONS: Ball games and nutrition counseling have a positive influence on postural control and therefore could help prevent injury. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01825174 . Registered April 2, 2013.

Pain threshold correlates with functional scores in osteoarthritis patients.

BACKGROUND AND PURPOSE: Pain sensitization may be one of the reasons for persistent pain after technically successful joint replacement. We analyzed how pain sensitization, as measured by quantitative sensory testing, relates preoperatively to joint function in patients with osteoarthritis (OA) scheduled for joint replacement. PATIENTS AND METHODS: We included 50 patients with knee OA and 49 with hip OA who were scheduled for joint replacement, and 15 control participants. Hip/knee scores, thermal and pressure detection, and pain thresholds were examined. RESULTS: Median pressure pain thresholds were lower in patients than in control subjects: 4.0 (range: 0-10) vs. 7.8 (4-10) (p = 0.003) for the affected knee; 4.5 (2-10) vs. 6.8 (4-10) (p = 0.03) for the affected hip. Lower pressure pain threshold values were found at the affected joint in 26 of the 50 patients with knee OA and in 17 of the 49 patients with hip OA. The American Knee Society score 1 and 2, the Oxford knee score, and functional questionnaire of Hannover for osteoarthritis score correlated with the pressure pain thresholds in patients with knee OA. Also, Harris hip score and the functional questionnaire of Hannover for osteoarthritis score correlated with the cold detection threshold in patients with hip OA. INTERPRETATION: Quantitative sensory testing appeared to identify patients with sensory changes indicative of mechanisms of central sensitization. These patients may require additional pain treatment in order to profit fully from surgery. There were correlations between the clinical scores and the level of sensitization.

Impaired jump landing after exercise in recreational and in high-performance athletes.

The risk of sustaining injuries increases with fatigue. The aim of this study was to analyze the influence of fatigue on dynamic postural control in jump landing and stabilization (ST) in athletes of different levels. In all, 18 high-performance ball sports athletes and 24 recreationally active subjects performed a jump test (JT) before and at 1, 5, 10, 15, and 20 minutes after a 30-minute treadmill run at the individual anaerobic threshold. An overhead ball switch hit during a forward jump triggered indicator lamps on either side of a force plate. After landing on the plate, ST on 1 leg (no light cue) or a second jump sideways (toward a light cue) was required. The ST force integral index was calculated for the ST trials. Dynamic postural control was significantly impaired in jump landing and ST in the first minute after the run: mean difference ± SD: 0.25 ± 0.48 m·s-1 (95% confidence interval: 0.10-0.40 m·s-1, p = 0.043; analysis of variance). No significant group differences were found. Under fatigued conditions, dynamic postural control in jump landing was impaired in an unexpected ST task. Not only recreational but also high-performance athletes were affected. Ball sports athletes could add a training exercise to their workout, which alternates between periods of high effort and neuromuscular training. Resistance to fatigue effects should be checked on a regular basis using JTs.

Altered force ratio in unanticipated side jumps after treadmill run.

OBJECTIVE: The aim was to investigate the influence of a run at the individual anaerobic threshold (IAT) on postural control in jumps with an unanticipated change of direction. HYPOTHESIS: Dynamic postural control is less affected by the run in trained athletes than in recreational ones. DESIGN: : Controlled prospective cohort study with an intervention. SETTING: Biomechanics laboratory. PARTICIPANTS: A total of 18 female high-level handball and volleyball players, 16 female and 8 male recreational athletes, with a mean age of 21.7 +/-4.1 years. INTERVENTIONS: In the jump test, the ball switch, hit above the force plate during a forward jump, triggers indicator lamps on either side. After landing on the dominant leg, a second jump 90 degrees sideways following a light signal or a stabilization in one-leg stance was required. Nine jumps (randomized order) were performed before and at 1, 5, 10, 15 and 20 min after a 30-min treadmill run at the IAT. MAIN OUTCOME MEASUREMENTS: For the second jump, the ratio of the absolute values of the maximum forces in anteroposterior and mediolateral direction was calculated as a parameter of dynamic postural control in the change of direction. RESULTS: In both groups, the force ratio increased significantly at 1 and 5 min after the treadmill run. The relative increase did not differ between groups. Dynamic postural control in transfer from a forward to a sideward jump was reduced after the run. Recovery occurred within 10 min. CONCLUSIONS: This study shows that dynamic postural control in jumps with an unanticipated change of direction is influenced by fatigue. These findings could be used to develop training programs aimed at reducing lower limb injuries in high-level ball sport athletes. The preventive effects have to be evaluated in further studies.

Modern Cartilage Imaging of the Ankle.

Background Talar osteochondral lesions are an important risk factor for the development of talar osteoarthritis. Furthermore, osteochondral lesions might explain persistent ankle pain. Early diagnosis of accompanying chondral defects is important to establish the optimal therapy strategy and thereby delaying or preventing the onset of osteoarthritis. The purpose of this review is to explain modern cartilage imaging with emphasis of MR imaging as well as the discussion of more sophisticated imaging studies like CT-arthrography or functional MR imaging. Methods Pubmed literature search concerning: osteochondral lesions, cartilage damage, ankle joint, talus, 2 D MR imaging, 3 D MR imaging, cartilage MR imaging, CT-arthrography, cartilage repair, microfracture, OATS, MACT. Results and Conclusion Dedicated MR imaging protocols to delineate talar cartilage and the appearance of acute and chronic osteochondral lesions were discussed. Recent developments of MR imaging, such as isotropic 3 D imaging that has a higher signal-to noise ratio when compared to 2 D imaging, and specialized imaging methods such as CT-arthrography as well as functional MR imaging were introduced. Several classifications schemes and imaging findings of osteochondral lesions that influence the conservative or surgical therapy strategy were discussed. MRI enables after surgery the non-invasive assessment of the repair tissue and the success of implantation. Key points · Modern MRI allows for highly resolved visualization of the articular cartilage of the ankle joint and of subchondral pathologies.. · Recent advances in MRI include 3 D isotropic ankle joint imaging, which deliver higher signal-to-noise ratios of the cartilage and less partial volume artifacts when compared with standard 2 D sequences.. · In case of osteochondral lesions MRI is beneficial for assessing the stability of the osteochondral fragment and for this discontinuity of the cartilage layer is an important factor.. · CT-arthrography can be used in case of contraindications of MRI and in unclear MRI findings as further diagnostic approach.. Citation Format · Weber MA, Wünnemann F, Jungmann PM et al. Modern Cartilage Imaging of the Ankle. Fortschr Röntgenstr 2017; 189: 945 - 956.

A marker placement laser device for improving repeatability in 3D-foot motion analysis.

BACKGROUND: In 3D gait analysis, the repeated positioning of markers is associated with a high error rate, particularly when using a complex foot model with many markers. Therefore, a marker placement laser device was developed that ensures a reliable repositioning of markers. We report the development and reliability of this device for the foot at different tape conditions. METHODS: In 38 subjects, markers were placed at the foot according to the Heidelberg foot measurement method. Subjects were tested barefoot and barefoot with three different tape conditions. For all conditions, a static standing trial was captured. We analyzed differences in distances between markers and the intra-class correlation coefficients (ICC). RESULTS: Small differences between the conditions (0.03-3.28 mm) and excellent ICCs (0.91-0.97 mm) were found for all parameters. CONCLUSION: The laser marker placement device appeared to be a reliable method to place markers on a tape at previously palpated positions and ensures an exact position. The device could find a wide application in different clinical research fields.

Foot kinematics in walking on a level surface and on stairs in patients with hallux rigidus before and after cheilectomy.

BACKGROUND: Walking down stairs is a clinically relevant daily activity for older persons. The aim of this pilot study was to investigate the impact of cheilectomy on walking on level ground and on stairs. METHODS: 3D motion analysis of foot kinematics was performed in eight patients with hallux rigidus and 11 healthy control participants with a 12-camera system, using the Heidelberg foot measurement method before and one year after surgery. The clinical results were documented using the AOFAS Scale. RESULTS: The range of motion of the first metatarsophalangeal joint did not improve after the operation under any gait condition. Preoperatively, hallux dorsi-/plantarflexion in level walking was 11.9° lower in patients than in controls (p = 0.006), postoperatively 14.5° lower (p = 0.004). Comparing walking conditions in patients, hallux dorsi-/plantarflexion was significantly higher in level walking than in climbing stairs (difference up stairs - level: -8.1°, p = 0.018).The AOFAS Scale improved significantly from 56.9 ± 19.9 points (mean ± SD), preoperatively, to 75.9 ± 13.9 points, postoperatively (p = 0.027). CONCLUSIONS: Cheilectomy is appropriate for reducing symptoms of hallux rigidus. However, neither a positive influence on the range of motion in walking on level ground and on stairs nor a functional improvement was observed in this group of patients. TRIAL REGISTRATION: NCT01804491.

Determining knee joint alignment using digital photographs.

The objective of this work is to find out how reliably knee joint alignment can be measured from a standardized photograph and what influence changes in the standing position have on the angles measured. The interrater, intrarater, and test-retest reliability were evaluated. The influence of image-object distance, the distance between the legs and leg rotation on the measured angles was evaluated. In addition to the digital photographs, 10 full-length radiographs were obtained in an upright position to determine whether the measured angles represent the anatomic axis or mechanical axis. There was high correlation between the interrater (ICC 0.997), intrarater (ICC 0.989) and test-retest reliability (ICC 0.904). Only slight deviation was found with the changes in radiograph-object distance (0 degrees -1.8 degrees ). With feet together varus malalignment was greater. Leg rotation showed a strong influence on the measured results (ICC 0.658). The angle measured in the digital photographs reflects the mechanical axis with only slight deviation (0.12 degrees -1.9 degrees ). The measurement of the clinical axis using standardized radiography is highly reliable and can be used for individual follow-up of varus and valgus malalignments.

Influence of professional dance training on peak torque and proprioception at the ankle.

OBJECTIVE: To investigate the influence of professional dance training on the peak torque ratio of plantar flexion to dorsiflexion (PF/DF), angle replication ability, and balance in comparison to age-matched and gender-matched controls. The effects of injuries sustained before and during the study time period were also assessed. DESIGN: Prospective age-matched and gender-matched nonrandomized intervention study. SETTING: Premises of the Orthopedic University Hospital, Heidelberg, where measuring apparatus belonging to the hospital was used for the tests. PARTICIPANTS: One group of 42 dancers (31 female, 11 male) in professional training (State Academy) and 40 age-matched and gender-matched controls with no prior dance or specific sport training. MAIN OUTCOME MEASUREMENTS: Isokinetic tests for peak torque at 30 degrees /s and 120 degrees /s, a passive angle-replication test (Biodex system 3), and a test of 1-legged standing were each carried out on 2 measurement dates (M1, M2): at the beginning of a season of professional dance training (M1) and after 5 months of such training (M2). Symptoms and/or injuries sustained during this period were ascertained continuously by means of questionnaires and interviews. RESULTS: A significant increase in peak torque in PF was observed in both dancer groups and male controls between M1 and M2. A significant increase in PF/DF peak torque ratio at 30 degrees /s was observed in both male groups between M1 and M2. At M2, no significant differences in PF/DF peak torque ratio could be found between male dancers and controls, but at 30 degrees /s between the female groups. However, in both female groups, the PF/DF ratio was not found to increase significantly between M1 and M2. In the angle-replication and 1-legged standing test, no consistent improvement was observed between M1 and M2 in either dancers or controls. In the angle-replication test, there were no significant differences between dancers and controls at M2. In the 1-legged standing test, the dancers did significantly better than controls. A total of 7 ankle injuries were recorded, but no difference was found between injured and uninjured subjects in the proprioceptive tests either at M1, as the predicator, or at M2 as the residual. CONCLUSIONS: Dance training did not increase the peak torque ratio of PF/DF within 5 months, but a group difference was found between the women groups. Ballet training alone without concurrent additional coordinative training does not lead to improvements in ankle joint position sense or improved measures of balance within this period of observation.