Trefoil Factor 3 (TFF3) Is Involved in Cell Migration for Skeletal Repair.

The aim of the study was to explore the possible role of Trefoil Factor Family peptide 3 (TFF3) for skeletal repair. The expression of TFF3 was analyzed in human joint tissues as well as in a murine bone fracture model. Serum levels of TFF3 following a defined skeletal trauma in humans were determined by ELISA. The mRNA expression of TFF3 was analyzed under normoxia and hypoxia. Expression analysis after stimulation of human mesenchymal progenitor cells (MPCs) with TFF3 was performed by RT2 Profiler PCR Array. The effect of recombinant human (rh)TFF3 on MPCs was analysed by different migration and chemotaxis assays. The effect on cell motility was also visualized by fluorescence staining of F-Actin. TFF3 was absent in human articular cartilage, but strongly expressed in the subchondral bone and periosteum of adult joints. Strong TFF3 immunoreactivity was also detected in murine fracture callus. Serum levels of TFF3 were significantly increased after skeletal trauma in humans. Expression analysis demonstrated that rhTFF3 significantly decreased mRNA of ROCK1. Wound healing assays showed increased cell migration of MPCs by rhTFF3. The F-Actin cytoskeleton was markedly influenced by rhTFF3. Cell proliferation was not increased by rhTFF3. The data demonstrate elevated expression of TFF3 after skeletal trauma. The stimulatory effects on cell motility and migration of MPCs suggest a role of TFF3 in skeletal repair.

Contrast-Enhanced Ultrasound as a New Investigative Tool in Diagnostic Imaging of Muscle Injuries-A Pilot Study Evaluating Conventional Ultrasound, CEUS, and Findings in MRI.

OBJECTIVE: To emphasize the diagnostic value of contrast-enhanced ultrasound (CEUS) in the imaging of muscle injuries with different degrees of severity by comparing findings to established imaging modalities such as conventional ultrasound and magnetic resonance imaging (MRI). DESIGN: Case series. SETTING: Institutional study. Conventional ultrasound and CEUS were performed in the Department of Internal Medicine. Magnetic resonance imaging was carried out in the Department of Radiology within the Magnetom Avanto 1.5T and Magnetom Skyra fit 3T (Siemens Healthineers, Erlangen, Germany) and in the Institution of Imaging Diagnostics and Therapy (Magnetom Avanto 1.5T; Siemens, Erlangen, Germany). PATIENTS: Fifteen patients who underwent an acute muscle injury were recruited. MAIN OUTCOME MEASURES: The appearance and detectable size of muscle injuries were compared between each imaging modality. The injuries were assessed by 3 independent observers and blinded between imaging modalities. RESULTS: All 15 injuries were identified on MRI and CEUS, whereas 10 injuries showed abnormalities in conventional ultrasound. The determination and measurement revealed significant differences between conventional ultrasound and CEUS depending on injury severity. Contrast-enhanced ultrasound revealed an impairment of microcirculation in grade I lesions (corresponding to intramuscular edema observed in MRI), which was not detectable using conventional ultrasound. CONCLUSIONS: Our results indicate that performing CEUS seems to be a sensitive additional diagnostic modality in the early assessment of muscle injuries. Our results highlight the advantages of CEUS in the imaging of low-grade lesions when compared with conventional ultrasound, as this was the more accurate modality for identifying intramuscular edema.

Application of Acoustic Radiation Force Impulse Elastography in Imaging of Delayed Onset Muscle Soreness: A Comparative Analysis With 3T MRI.

CONTEXT: Delayed onset muscle soreness is one of the most common reasons for impaired muscle performance in sports and is associated with reduced muscle strength and frequently observed both in professional and recreational athletes. OBJECTIVE: To emphasize the diagnostic value of acoustic radiation force impulse (ARFI) in imaging of delayed onset muscle soreness by comparing findings with high-resolution 3T magnetic resonance imaging T2-weighted sequences. DESIGN: Case series. SETTING: Laboratory environment. PARTICIPANTS: Fifteen healthy students (7 females and 8 males; mean [SD]: age 24 [4] y, height 178 [10] cm, body weight 67 [12] kg). MAIN OUTCOME MEASURES: ARFI values, represented as shear wave velocities of the gastrocnemius muscle and soleus muscle, as well as conventional ultrasound, high-resolution 3T magnetic resonance imaging, creatine kinase activity, extension range of the ankle joint, calf circumference, and muscle soreness were assessed before (baseline) and 60 hours after (postintervention) a standardized eccentric exercise. RESULTS: ARFI shear wave velocity values of the gastrocnemius muscle revealed a statistically significant decrease of 19.1% between baseline (2.2 [0.26] m/s) and postintervention (1.78 [0.24] m/s); P = .01. At follow-up, the magnetic resonance imaging investigations showed intramuscular edema for the gastrocnemius muscle in all participants corresponding to a significant raise in T2 signal intensity (P = .001) and in T2-time values (P = .004). CONCLUSIONS: ARFI elastography seems to be an additional sensitive diagnostic modality in the diagnostic workup of delayed onset muscle soreness. Intramuscular shear wave velocities could represent an additional imaging marker for the assessment and monitoring of ultrastructural muscle injuries and therefore be helpful for individual training composition in elite sports.

Intramuscular Perfusion Response in Delayed Onset Muscle Soreness (DOMS): A Quantitative Analysis with Contrast-Enhanced Ultrasound (CEUS).

The purpose of this study was to analyse intramuscular perfusion response in ultrastructural muscle lesions, by applying contrast-enhanced ultrasound (CEUS) to a delayed onset muscle soreness (DOMS) model. Results of this analysis were compared to high-resolution 3 Tesla MRI T2-weighted sequences. 14 healthy participants were recruited. Average perfusion parameters, represented as Peak enhancement (contrast agent inflow) and wash-in area under curve (WiAUC) of the gastrocnemius (GM) and soleus muscle (SM) were assessed before (baseline) and 60 h after inducing DOMS by eccentric exercise. Additionally, conventional ultrasound, high-resolution 3T MRI, creatine kinase level, range of motion (ROM) of the ankle joint, calf circumference and muscle soreness data were collected. Perfusion quantification revealed a statistically significant increase of intramuscular perfusion, corresponding to an increase in peak enhancement of 129.6% (p=0.0031) and in WiAUC of 115.2% (p=0.0107) in the gastrocnemius muscle at post-intervention. At follow-up, the MRI investigations showed intramuscular oedema for GM in all participants corresponding to a significant rise in T2 signal intensity (p=0.001) and in T2 time value (p=0.005). CEUS seems to be able to detect intramuscular perfusion changes and therefore may contribute to gaining deeper insight into the histopathology, inflammatory reactions and regeneration processes of ultrastructural muscle lesions.

Acute Effects of Lateral Thigh Foam Rolling on Arterial Tissue Perfusion Determined by Spectral Doppler and Power Doppler Ultrasound.

Hotfiel, T, Swoboda, B, Krinner, S, Grim, C, Engelhardt, M, Uder, M, and Heiss, R. Acute effects of lateral thigh foam rolling on arterial tissue perfusion determined by spectral Doppler and power Doppler ultrasound. J Strength Cond Res 31(4): 893-900, 2017-Foam rolling has been developed as a popular intervention in training and rehabilitation. However, evidence on its effects on the cellular and physiological level is lacking. The aim of this study was to assess the effect of foam rolling on arterial blood flow of the lateral thigh. Twenty-one healthy participants (age, 25 ± 2 years; height, 177 ± 9 cm; body weight, 74 ± 9 kg) were recruited from the medical and sports faculty. Arterial tissue perfusion was determined by spectral Doppler and power Doppler ultrasound, represented as peak flow (Vmax), time average velocity maximum (TAMx), time average velocity mean (TAMn), and resistive index (RI), and with semiquantitative grading that was assessed by 4 blindfolded investigators. Measurement values were assessed under resting conditions and twice after foam rolling exercises of the lateral thigh (0 and 30 minutes after intervention). The trochanteric region, mid portion, and distal tibial insertion of the lateral thigh were representative for data analysis. Arterial blood flow of the lateral thigh increased significantly after foam rolling exercises compared with baseline (p ≤ 0.05). We detected a relative increase in Vmax of 73.6% (0 minutes) and 52.7% (30 minutes) (p < 0.001), in TAMx of 53.2% (p < 0.001) and 38.3% (p = 0.002), and in TAMn of 84.4% (p < 0.001) and 68.2% (p < 0.001). Semiquantitative power Doppler scores at all portions revealed increased average grading of 1.96 after intervention and 2.04 after 30 minutes compared with 0.75 at baseline. Our results may contribute to the understanding of local physiological reactions to self-myofascial release.

Signature of circulating microRNAs in osteoarthritis.

BACKGROUND: Osteoarthritis is the most common form of arthritis and a major socioeconomic burden. Our study is the first to explore the association between serum microRNA levels and the development of severe osteoarthritis of the knee and hip joint in the general population. METHODS: We followed 816 Caucasian individuals from 1995 to 2010 and assessed joint arthroplasty as a definitive outcome of severe osteoarthritis of the knee and hip. After a microarray screen, we validated 12 microRNAs by real-time PCR in the entire cohort at baseline. RESULTS: In Cox regression analysis, three microRNAs were associated with severe knee and hip osteoarthritis. let-7e was a negative predictor for total joint arthroplasty with an adjusted HR of 0.75 (95% CI 0.58 to 0.96; p=0.021) when normalised to U6, and 0.76 (95% CI 0.6 to 0.97; p=0.026) after normalisation to the Ct average. miRNA-454 was inversely correlated with severe knee or hip osteoarthritis with an adjusted HR of 0.77 (95% CI 0.61 to 0.97; p=0.028) when normalised to U6. This correlation was lost when data were normalised to Ct average (p=0.118). Finally, miRNA-885-5p showed a trend towards a positive relationship with arthroplasty when normalised to U6 (HR 1.24; 95% CI 0.95 to 1.62; p=0.107) or to Ct average (HR 1.30; 95% CI 0.99 to 1.70; p=0.056). CONCLUSIONS: Our study is the first to identify differentially expressed circulating microRNAs in osteoarthritis patients necessitating arthroplasty in a large, population-based cohort. Among these microRNAs, let-7e emerged as potential predictor for severe knee or hip osteoarthritis.

Incompliance of total hip arthroplasty (THA) patients to limited weight bearing.

INTRODUCTION: Limited weight bearing of the lower extremity is a commonly applied procedure in orthopedic rehabilitation following trauma surgery and joint replacement. The compliance of patients with limited weight bearing after cementless total hip arthroplasty has not yet been surveyed using sensor-loaded insoles. The objective of this study was to investigate foot loadings in patients after THA under the assumption of limited weight bearing. METHODS: Peak pressures for the hindfoot, midfoot and forefoot were obtained from 14 patients (10 women, 4 men, age 63 ± 12 years, height 172 ± 9 cm, weight 92 ± 20 kg, BMI 31 ± 6 kg/m(2)) by means of dynamic pedobarography, with full weight bearing preoperatively (baseline) and at 8-10 days after cementless total hip arthroplasty, walking again on even floor, and also walking upstairs and downstairs with a restriction of weight bearing to 10 % body weight, taught by an experienced physiotherapist with a bathroom scale. RESULTS: Foot loadings with limited weight bearing on even floor remained up to 88 % from full weight bearing preoperatively. Walking upstairs and downstairs under the same condition was approximately equal to a bisection of peak pressures from full weight bearing. CONCLUSIONS: Patients following cementless do not comply with limited weight bearing when they are trained by the use of a bathroom scale.

Soccer boots elevate plantar pressures in elite male soccer professionals.

OBJECTIVE: The present study measured the difference in peak plantar pressure between running shoes and soccer shoes in male soccer professionals [mean (SD): age, 23 (4) years; height, 184 (7) cm; weight, 81 (6) kg]. DESIGN: Case series. SETTING: Institutional study. PARTICIPANTS: A total of 17 elite male soccer professionals [mean (SD): age, 23 (4) years; height, 184 (7) cm; weight 81 (6) kg]. INTERVENTIONS: Fifteen right and left steps with sensor-loaded insoles (99 sensors, 50 Hz) while running (3.3 m/s) in running shoes and then chosen soccer shoes (12-stud profile). The players were equipped with running shoes from the supplier without any medical supervision. MAIN OUTCOME MEASURES: Changes of peak plantar pressure for 9 defined foot portions between soccer boots and running shoes. RESULTS: A statistically significant increase of peak plantar pressure was found for the lateral midfoot (P < 0.001 for preferred and nonpreferred foot), the first metatarsal head (preferred foot: P < 0.001, nonpreferred foot: P = 0.002), the metatarsal heads 4/5 (preferred foot: P = 0.001, nonpreferred foot: P = 0.002), and the big toe (preferred foot: P = 0.001, nonpreferred foot: P < 0.001), but not for the lateral and medial hindfoot, the medial midfoot, and lesser toes. CONCLUSIONS: In running, soccer boots generate excessive foot loadings predominantly under the lateral midfoot, as compared with running shoes. Players should be trained with a thoughtfully designed workout regimen that allows performing as many straight running exercises as possible in running shoes instead of soccer boots. This may help to prevent fifth metatarsal stress fractures in elite male soccer players.

Chondromodulin 1 stabilizes the chondrocyte phenotype and inhibits endochondral ossification of porcine cartilage repair tissue.

OBJECTIVE: To investigate the effect of chondromodulin 1 on the phenotype of osteochondral progenitor cells in cartilage repair tissue. METHODS: Self-complementary adeno-associated virus (AAV) vectors carrying chondromodulin 1 complementary DNA (AAV-Chm-1) were applied to cartilage lesions in the knee joints of miniature pigs that were treated by the microfracture technique. Alternatively, isolated porcine osteochondral progenitor cells were infected with AAV-Chm-1 or with AAV-GFP control vectors ex vivo prior to being transplanted into cartilage lesions in which the subchondral bone plate was left intact. The quality of the repair tissue and the degree of endochondral ossification were assessed by histochemical and immunohistochemical methods. The effects of chondromodulin 1 overexpression were also analyzed by angiogenesis assays and quantitative reverse transcriptase-polymerase chain reaction. RESULTS: AAV-Chm-1-infected cells efficiently produced chondromodulin 1, which had strong antiangiogenic effects, as verified by the inhibition of tube formation of endothelial cells. Gene expression analyses in vitro revealed the cell cycle inhibitor p21WAF1/Cip1 as one target up-regulated by AAV-Chm-1. Direct application of AAV-Chm-1 vectors into microfractured porcine cartilage lesions stimulated chondrogenic differentiation of ingrowing progenitor cells, but significantly inhibited terminal chondrocyte hypertrophy, the invasion of vessel structures, and excessive endochondral ossification, which were otherwise observed in untreated lesions. Indirect gene transfer, with infection of porcine osteochondral progenitor cells by AAV-Chm-1 ex vivo, also supported chondrogenic differentiation of these transplanted cells. AAV-Chm-1-infected cells maintained a chondrocyte-like phenotype and formed a hyaline-like matrix that was superior to that formed by uninfected or AAV-GFP-infected cells. CONCLUSION: Our findings indicate that the antiangiogenic factor chondromodulin 1 stabilizes the chondrocyte phenotype by supporting chondrogenesis but inhibiting chondrocyte hypertrophy and endochondral ossification.

Foot loading with an ankle-foot orthosis: the accuracy of an integrated physical strain trainer.

PURPOSE: To investigate the value of a built-in physical strain trainer for the monitoring of partial weight bearing with an ankle-foot orthosis. METHODS: 12 healthy volunteers were asked to perform three trials. Plantar peak pressure values from normal gait (trial one) were defined as 100% (baseline). The following trials were performed with the Vacoped® dynamic vacuum ankle orthosis worn in a neutral position with full weight bearing (trial two) and a restriction to 10% body weight (BW) (trial three), as monitored with an integrated physical strain trainer. Peak plantar pressure values were obtained using the pedar® X system. RESULTS: Peak pressure values were statistically significantly reduced wearing the Vacoped® shoe with full weight bearing for the hindfoot to 68% of the baseline (normal gait) and for the midfoot and forefoot to 83% and 60%, respectively. Limited weight bearing with 10% BW as controlled by physical strain trainer further reduced plantar peak pressure values for the hindfoot to 19%, for the midfoot to 43% of the baseline and the forefoot to 22% of the baseline. CONCLUSIONS: The Vacoped® vacuum ankle orthosis significantly reduces plantar peak pressure. The integrated physical strain trainer seems unsuitable to monitor a limitation to 10% BW adequately for the total foot. The concept of controlling partial weight bearing with the hindfoot-addressing device within the orthosis seems debatable but may be useful when the hindfoot in particular must be off-loaded.

Inaccuracy of a physical strain trainer for the monitoring of partial weight bearing.

OBJECTIVE: To investigate the use of a physical strain trainer for the monitoring of partial weight bearing. DESIGN: Case series with healthy volunteers. SETTING: Orthopedic clinic. PARTICIPANTS: Healthy volunteers (N=10) with no history of foot complaints. INTERVENTIONS: Volunteers were taught to limit weight bearing to 10% body weight (BW) and 50% BW, monitored by a physical strain trainer. MAIN OUTCOME MEASURES: The parameters peak pressure, maximum force, force-time integral, and pressure-time integral were assessed by dynamic pedobarography when volunteers walked with full BW (condition 1), 50% BW (condition 2), and 10% BW (condition 3). RESULTS: With 10% BW (condition 3), forces with normative gait (condition 1) were statistically significantly reduced under the hindfoot where the physical strain trainer is placed. All pedobarographic parameters were, however, exceeded when the total foot was measured. A limitation to 10% BW with the physical strain trainer (condition 3) was equal to a bisection of peak pressure and maximum force for the total foot with normative gait (condition 1). Halved BW (condition 2) left a remaining mean 82% of peak pressure and mean 59% of maximum force from full BW (condition 1). CONCLUSIONS: The concept of controlling partial weight bearing with the hindfoot-addressing device does not represent complete foot loading. Such devices may be preferably applied in cases when the hindfoot in particular must be off-loaded. Other training devices (eg, biofeedback soles) that monitor forces of the total foot have to be used to control partial weight bearing of the lower limb accurately.

Cementless total hip arthroplasty in patients with rheumatoid arthritis using a tapered designed titanium hip stem minimum: 10-year results.

The results of cementless tapered designed femoral stem were studied at a minimum 10-year follow-up in a non-selected, consecutive group of 27 patients (39 hips) with rheumatoid arthritis. Clinical and radiological analyses were performed in 27 hips, 17 patients (mean age at surgery 45 years) after a mean of 12 years. The postoperative Harris hip score was excellent for 14 hips, 9 hips were rated as good and 4 hips were fair or poor. No stem had to be revised for aseptic loosening. Proximal stress shielding was observed in 26 hips (96%); heterotopic ossification was present in 11 hips (41%). Six hips required revision of the acetabular component. With uncemented tapered femoral fixation excellent 12-year results are achieved in patients with rheumatoid arthritis.

Combined arthroscopic and radiation synovectomy of the knee joint in rheumatoid arthritis: 14-year follow-up.

PURPOSE: To investigate the long-term outcome of combined arthroscopic and radiation synovectomy of the knee joint in early cases of rheumatoid arthritis (RA) with regard to knee function and the need for surgical re-interventions. METHODS: Between 1993 and 1997, a consecutive series of 38 RA patients with therapy-refractory synovitis of the knee joint and only mild cartilage lesions (not exceeding Outerbridge grade II at surgery) were treated with combined arthroscopic and radiation synovectomy. Knee function was assessed preoperatively; at 6 months, 1 year, and 5 years; and finally, at a mean of 14 years with 4 different functional scores. A Kaplan-Meier survival curve was calculated with "any re-intervention" and "total knee arthroplasty" as endpoints. RESULTS: Of 38 knees, 32 were available for the final 14-year follow-up with a total of 22 re-interventions: intra-articular steroid injection (n = 3), arthroscopic (n = 2) or radiation (n = 1) re-synovectomy, and total knee arthroplasty (n = 16). The remaining 10 patients with no re-intervention showed knee function not significantly different from the postoperative state. With any surgical re-intervention as the endpoint, the survival rate was 84% at 5 years (95% confidence interval [CI], 67.0% to 86.7%), 44% at 10 years (95% CI, 26.7% to 60.0%), and 32% at the 14-year assessment (95% CI, 16.0% to 49.3%). With total knee arthroplasty as the endpoint, the joint survival rate was 88.5% at 5 years (95% CI, 68.5% to 96.2%), 53.9% at 10 years (95% CI, 33.3% to 71.6%), and 39.6% at 14 years (95% CI, 18.9% to 48.6%). CONCLUSIONS: Combined arthroscopic and radiation synovectomy leads to a stable improvement of knee function for a minimum of 5 years, but surgical re-interventions were frequently observed at the 14-year assessment and challenge the long-term benefit of the procedure. Patients with no interventions had a significantly shorter history of disease (7 v 11 years). LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Assessing Foot Loads in Continuous Passive Motion (CPM) and Active Knee Joint Motion Devices.

BACKGROUND: Continuous passive motion (CPM) and active knee joint motion devices are commonly applied after various surgical procedures. Despite the growing use of active motion devices, there is a paucity of data comparing plantar loads between the different mobilization techniques. The aim of this study was to investigate foot loads during knee joint mobilization in continuous passive and active knee joint motion devices and to compare this data to the physiological load of full weight-bearing. PATIENTS/MATERIAL AND METHODS: Fifteen healthy participants (7 women and 8 men, 25 ±â€Š3 years, 66 ±â€Š6 kg, 175 ±â€Š10 cm, BMI 21.9 ±â€Š2) were recruited. Plantar loads were measured via dynamic pedobarography using a continuous passive motion device (ARTROMOT-K1, ORMED GmbH, Freiburg, Germany) and an active motion device (CAMOped, OPED AG, Cham, Switzerland), each with a restricted range of motion of 0-0-90° (ex/flex) and free ROM for the knee joint. For the active motion device, cycles were performed at four different resistance levels (0-III). Data were assessed using the pedar® X system (Novel Inc., Munich, Germany), which monitors loads from the foot-sole interface. Force values were compared between motion devices and normal gait, which served as the reference for conditions of full weight-bearing. P-values of < 0.05 were considered statistically significant. RESULTS: Normal gait revealed peak forces of 694 ±â€Š96 N, defined as 100 %. The CPM device produced plantar forces of less than 1.5 N. Using the active motion device in the setting of 0-0-90° produced foot loads of < 1.5 N (resistance 0-II) and 3.4 ±â€Š9.3 N with a resistance of III (p < 0.001). Conditions of free ROM resulted in foot loads of 4.5 ±â€Š4.5 N (resistance 0), 7.7 ± 10.7 N (resistance I), 6.7 ±â€Š10.4 (resistance II) and 6.7 ±â€Š6.9 N with a resistance of III (p < 0.001), corresponding to 0.6 %, 1.1 %, 1.0 % and 1.0 % of full weight-bearing, respectively. CONCLUSION: Motion exercises of the knee joint can be performed both with passive and active devices in accordance with strict weight-bearing restrictions, which are often recommended by surgeons. Also, active motion devices can be used when the ankle joint or foot have to be offloaded. Further studies assessing intraarticular joint load conditions have to be performed to confirm the findings obtained in this study.

A cross-sectional study on foot loading patterns in elite soccer players of different ages.

BACKGROUND: Alterations in plantar loading patterns are risk factors for stress injuries of the lower limb, particularly of the foot and ankle. Epidemiological studies have revealed a higher incidence of soccer-related stress fractures of the fifth metatarsal (MT V) in younger athletes than in their adult counterparts. OBJECTIVE: The aim of the present study was to assess the plantar pressure distributions of members of four high-level soccer teams of different age groups to identify age-related differences in loading patterns. METHODS: A total of 65 elite soccer players were included in the study. Data were computed with sensor-loaded insoles (pedar® X system, novel Inc., Munich, Germany) while the players ran in soccer shoes. Plantar pressures for nine defined regions on the preferred and nonpreferred foot were analyzed. RESULTS: The participants consisted of 17 elite male soccer professionals from the first national league (mean 23 years, height 184 cm, weight 81 kg), 14 players from the under-21 squad (U21, 20 years, 180 cm, 75 kg), 15 players from the U17 squad (16 years, 176 cm, 69 kg) and 19 players from the U16 squad (15 years, 179 cm, 70 kg). We detected statistically significantly elevated peak pressures on the lateral aspects of the nonpreferred foot compared with the preferred foot in the U16 and U17 players, corresponding to a relative increase by 29% (p= 0.044) in the lateral midfoot, a relative increase by 24% (p= 0.031) in MT heads 4-5 in the U16 players and a difference of 18% (p= 0.049) in the lateral midfoot in the U17 players. In contrast, the U21 and adult professional players displayed symmetric plantar pressure distributions in all foot regions. CONCLUSIONS: In contrast to adult elite soccer players, adolescents demonstrate asymmetric foot loading patterns with increased peak loads in the lateral aspects of the nonpreferred foot. Our results may provide some explanation for MT V stress fractures that occur in elite adolescents.

Effect of Compression Garments on the Development of Delayed-Onset Muscle Soreness: A Multimodal Approach Using Contrast-Enhanced Ultrasound and Acoustic Radiation Force Impulse Elastography.

BACKGROUND: Delayed-onset muscle soreness (DOMS) is one of the most common reasons for impaired muscle performance in sports. However, little consensus exists regarding which treatments may be most effective, and the underlying mechanisms are poorly understood. OBJECTIVES: To investigate the influence of compression garments on the development of DOMS, focusing on changes in muscle perfusion and muscle stiffness. METHODS: In this controlled laboratory study with repeated measures, muscle perfusion and stiffness, calf circumference, muscle soreness, passive ankle dorsiflexion, and creatine kinase levels were assessed in participants before (baseline) a DOMS-inducing eccentric calf exercise intervention and 60 hours later (follow-up). After DOMS induction, a sports compression garment (18-21 mmHg) was worn on 1 randomly selected calf until follow-up, while the contralateral calf served as an internal control. Muscle perfusion was assessed using contrast-enhanced ultrasound (peak enhancement and wash-in area under the curve), while muscle stiffness was assessed using acoustic radiation force impulse (shear-wave velocities). A magnetic resonance imaging scan of both lower legs was also performed during the follow-up testing session to characterize the extent of exercise-induced muscle damage. Comparisons were made between limbs and over time. RESULTS: Shear-wave velocity values of the medial gastrocnemius showed a significant interaction between time and treatment (P = .006), with the noncompressed muscle demonstrating lower muscle stiffness values at follow-up compared to baseline or to the compressed muscle. No significant differences in soleus muscle stiffness were noted between limbs or over time, as was the case for muscle perfusion metrics (peak enhancement and wash-in area under the curve) for the medial gastrocnemius and soleus muscles. Further, compression had no significant effect on passive ankle dorsiflexion, muscle soreness, calf circumference, or injury severity, per magnetic resonance imaging. CONCLUSION: Continuous wearing of compression garments during the inflammation phase of DOMS may play an important role in regulating muscle stiffness; however, compression garments have no significant effects on intramuscular perfusion or other common clinical assessments. J Orthop Sports Phys Ther 2018;48(11):887-894. Epub12 Jun 2018. doi:10.2519/jospt.2018.8038.

Synovectomy of the hip in patients with juvenile rheumatoid arthritis.

BACKGROUND: There is a lack of data on the functional effect of open hip synovectomy in a large number of patients with juvenile rheumatoid arthritis evaluated with a validated assessment tool. METHODS: Between 1985 and 1997, sixty-seven open hip-joint synovectomies were carried out in fifty-six patients with juvenile rheumatoid arthritis. Fifty-five hips (82%) had radiographic changes that were stage III or higher according to the system of Larsen et al. Hip function was evaluated preoperatively and after a mean of fifty months with the Merle d'Aubigné hip score. RESULTS: Sixty-five (97%) of the sixty-seven hips were available for follow-up. The mean total Merle d'Aubigné hip score (and standard error of the mean) was significantly improved from 9.5 +/- 2.5 points at baseline to 16.3 +/- 1.0 points at the time of follow-up (p < 0.001). The individual scores for pain, mobility, and walking ability were significantly increased as well (all p < 0.001). Eighty-five percent of the hips were observed to have a very great or great improvement in function. A concomitant soft-tissue release was performed in seven hips, and nine hips required surgical dislocation. Surgical complications included two superficial wound hematomas that did not require intervention; osteonecrosis of the femoral head was not observed. Five hips required total hip arthroplasty during the follow-up period. Thus, the survival rate for the hips was 94% at a mean of four years following the synovectomy. CONCLUSIONS: Open hip synovectomy in patients with juvenile rheumatoid arthritis is a safe procedure that can improve hip-joint function for up to five years.

Cementless femoral components in bicondylar hybrid knee arthroplasty in patients with rheumatoid arthritis: A 10-year survivorship analysis.

BACKGROUND: Total knee arthroplasty (TKA) has been established as a successful surgical treatment in the late stages of rheumatoid joint destruction. The purpose of this study was to review the clinical outcome and survivorship in rheumatoid arthritis (RA) patients undergoing TKA in hybrid technique with a cementless fixation of the femoral component. METHODS: We analysed retrospectively 66 RA patients who underwent 72 TKAs (P.F.C. Sigma®). Mean follow-up time was 124 ± 41 months. To evaluate postoperative clinical outcome, knee injury and osteoarthritis outcome score (KOOS) and Oxford knee score (OKS) were assessed. Kaplan-Meier analysis was used to calculate survivorship. The primary outcome was revision for any reason. RESULTS: Thirty-four patients (36 knees) died and two patients (2 knees) were lost to follow-up. Three patients (four knees) did not agree to participate. Twenty-seven patients (30 knees) were available for assessing clinical scores. The average scores were 85 ± 14 for KOOS and 34 ± 10 for OKS. In three patients (three knees), revision was necessary, including restricted range of motion ( n = 1), instability ( n = 1), and infection ( n = 1). There were no cases of loosening in this cohort study. The survival rates were 100% at 5 years, 97.1% at 10 years (95% CI 89.0-99.2%) and 95.6% at 15 years (95% CI 86.9-98.5%). CONCLUSIONS: This study confirms that excellent clinical results and a good 10-year survivorship can be obtained with hybrid fixation technique in TKA in the unique population of RA patients.

Assessment of plantar pressure in forefoot relief shoes of different designs.

BACKGROUND: After reconstructive forefoot surgery, patients require complete or partial forefoot relief, which can be obtained with a variety of shoe designs. The aim of this study was to evaluate the effectiveness of two different types of forefoot-relief shoes frequently used after surgery, especially their safety against unintentional forefoot load. METHODS: Ten healthy volunteers were asked to perform five trials on a treadmill at self-selected speeds. In the first trial, mean peak pressure values in mass-produced shoes and insoles were evaluated and considered as 100%. Two different shoe designs (short heel-short sole, ii: short heel-complete sole) were compared in two trials each with appropriate and inappropriate use (attempting to put weight on the forefoot) gait pattern. Plantar pressure values were obtained using the Pedar cable system (Novel Inc., Munich, Germany). For analysis, pedobarographic pictures were subdivided into midfoot (31% to 60% of the total insole length) and forefoot (61% to 100% of the total insole length). ANOVA was used for statistical analysis, and p values less than 0.01 were considered significant. RESULTS: With the short-soled shoe, forefoot and midfoot relief was 100% in both compliant and in noncompliant use. With wearing a complete sole, compliant use led to a significant reduction (p < 0.01) of mean peak pressure under the forefoot (34 +/- 13% remaining) and midfoot (47 +/- 13% remaining). Noncompliant use of the complete-sole shoe produced mean peak pressure values significantly higher (p < 0.01) than normal gait in mass produced shoes under the forefoot, but not under the midfoot. CONCLUSIONS: Forefoot-relief shoes are effective in reducing both mean and peak plantar pressures. Shoes with a nonsupported midfoot and forefoot may be safer with inappropriate use than shoes with a complete sole. The kind of forefoot shoe should be carefully chosen to regulate weightbearing after reconstructive forefoot surgery.

How do leg press exercises comply with limited weight bearing?

OBJECTIVES: To investigate foot loadings in different leg press settings with respect to a possible graduation of weight bearing (WB). DESIGN: Case series. SETTINGS: Assessing plantar force values by means of dynamic pedobarography taken place in orthopaedic departments' rehab center. PARTICIPANTS: 15 healthy students (9 men and 6 women, age 23 ± 2, weight 75 ± 6 kg) were recruited as participants from the medical faculty. MAIN OUTCOME MEASURES: Peak force values from normal gait (referred to as 100%) and single and double leg presses (SLP, DLP) with resistances of 10 kg, 20 kg and 40 kg, obtained with pedobarographic insoles. RESULTS: Performing DLP produced foot loadings (N) of 37 ± 15 with 10 kg, 91 ± 29 with 20 kg and 203 ± 27 with 40 kg, equal to 5%, 12% and 26% of full WB. SLP result in force values of 195 ± 32 with 10 kg, 308 ± 34 with 20 kg and 516 ± 45 with 40 kg, corresponding to 25%, 40% and 67% baseline. CONCLUSIONS: Leg press exercises can be performed in accordance with a given limitation of foot loading. Above mentioned conditions allow a graduation from 5% to 67% of full WB.