Purpose: Repetitive and asymmetric movements in tennis can result in biomechanical adaptation in shoulder joint. The aim of this study was to investigate the differences in shoulder range of motion (ROM), strength, and functional performance tests between the dominant and nondominant shoulders, as well as to identify gender differences in junior tennis players. Methods: Forty-two junior tennis players (age mean: 11.3 [1.2] y, body mass index 18.3 [2.4] kg/m2) were included in the study. Shoulder internal rotation (IR), external rotation (ER) ROM, and total ROM, IR and ER isokinetic strength and closed kinetic chain upper-extremity stability, seated medicine ball throw used, grip hold tests were applied bilaterally. Paired sample t test and Student t test were used to compare the differences. Results: ER ROM was greater, while IR ROM and total ROM were lower on the dominant shoulder (all P values < .05). Nineteen players had glenohumeral IR deficit (IR ROM difference >13°). The players had a greater ER strength on the dominant side and similar IR strength between shoulders. There was significant difference in seated medicine ball throw results between the dominant and nondominant sides (P < .001). The mean distance for bilateral seated medicine ball throw was 377.02 (85.70) m, and closed kinetic chain upper-extremity stability results were calculated as a mean of 15.85 (1.72) touches. Differences between the genders: total ROM of the dominant shoulder was higher in female players (P = .045), the IR PT/BW at 60°/s angular speed was higher in male players’ dominant shoulder (P = .030), and closed kinetic chain upper-extremity stability performance was higher in male players (P = .019). Conclusions: Adolescent tennis players demonstrated differences in strength, ROM, and functional performance results between the dominant and nondominant shoulders. Gender differences were also seen in the aforementioned parameters in junior tennis players. Determining these differences may improve our understanding of sport-specific shoulder joint adaptations in tennis.

Tenis oyuncularında omuz performansı ile ilişkili birçok faktör bulunmaktadır. Bu çalışmanın amacı, adolesan tenis oyuncularının üst ekstremite performans parametreleri ile omuz rotator kas kuvveti arasındaki ilişkiyi incelemekti.Yöntem: Çalışmaya 10 ile 18 yaş arası 31 adolesan tenis oyuncusu dahil edildi. Üst ekstremite performansını belirlemede sağlık topu fırlatma, kapalı kinetik zincir üst ekstremite stabilite testi ve kavrama kuvveti testi kullanıldı. Omuz rotator izokinetik kas kuvveti ISOMED 2000 (D&R GmbH, Almanya) sistemi ile değerlendirildi. İstatistiksel analizde doğrusal regresyon analizi kullanıldı.Sonuçlar: Sağlık topu fırlatma mesafesi ile 60°/s açısal hızda internal rotator (İR) tepe tork (TT) (r=0,535, p=0,002) ve eksternal rotator (ER) TT (r=0,421, p=0,018) değerleri arasında pozitif yönde orta düzeyde ilişki bulundu. Kavrama kuvveti ile 60°/s İR-TT (r=0,647, p=0,001) ve ER-TT (r=0,645, p=0,001) değerleri arasında güçlü düzeyde ilişki bulundu. Kapalı kinetik zincir üst ekstremite stabilite test sonuçları ile 60°/s ER TT arasında ilişki saptandı (r=0,391, p=0,029). Tartışma: Çalışmanın sonucunda; adolesan tenis oyuncularında omuz rotator kas kuvveti artıkça omuz performansının arttığı görüldü. Tenis oyuncularında performansı etkileyen faktörlerin adolesan dönemde saptanması, performansı arttırmak ve koruyucu yönde önlemler almak için oldukça önemlidir.

Purpose: Scapular dyskinesis is defined as alteration in scapular movements due to the loss of strength in scapular muscles; tightness of the soft tissues around shoulder and postural problems. Proprioceptive neuromuscular facilitation (PNF) is one of the therapeutic exercises to improve muscles weakness and pain levels. The aim of this study was to investigate the effects of a six-week PNF application on scapular muscle strength, scapular asymmetry, and pectoralis minor (PM) muscle tightness in participants with asymptomatic scapular dyskinesis. Methods: Twenty-five asymptomatic participants were evaluated using the video analysis method to determine the scapular dyskinesis. Eleven of them diagnosed with scapular dyskinesis and recruited for the PNF application. Lateral scapular slide test (LSST); tightness of PM; the muscle strength of serratus anterior (SA); lower trapezius (LT) and upper trapezius (UT) were evaluated. Anterior elevation-posterior depression; posterior elevation-anterior depression of PNF patterns were applied as repeated contractions technique by 2 times a week for 6 weeks. Results: The LT (p=0.012) and SA (p=0.035) muscle strength increased following PNF training, while UT muscle strength was similar (p>0,05). The UT/SA (p=0.035) and UT/LT (p=0.012) strength ratios decreased following PNF application. The mean differences of PM tightness and LSST did not exceed the established MDC%95. Conclusion: Scapular muscle balance improved following scapular PNF training. Therefore, scapular PNF patterns would be considered as an alternative treatment option to provide scapular stabilization and increase muscle strength.

BackgroundOsteoarthritis (OA) of the knee is a common degenerative and chronic disease as well as a major cause of knee pain and functional disability. Alterations in lower extremity biomechanics may lead adaptive changes in walking, foot pressure distribution, lower extremity muscle strength as well as the architectural characteristics of the knee and ankle muscles in patients with knee OA.ObjectivesThe aim of this study was to compare the knee and ankle muscle architecture and foot pressure distribution differences in knee OA patients with healthy individuals.MethodsTwenty patients with knee OA (mean age= 53.35±1.21 years, mean BMI=31.69±0.93 kg/m2) and twenty healthy controls (mean age= 51.05±0.63 years, mean BMI=29.28±1.15 kg/m2) were included in the study. Rectus Femoris (RF), Vastus Medialis (VM), Peronalis Longus (PL) and Medial Gastrocnemius (MG) muscles thickness, pennation angle and fat thickness were evaluated using B-Mode ultrasonography (Esaote MyLab X8 eXP Ultrasound System, Florence, Italy). Ultrasound images were analyzed offline using an image analysis software (Image J, National Institutes of Health, Bethesda, MD, USA) program. Plantar pressure distribution was evaluated using the Digital Biometry Scanning System and Milletrix software (DIASU, Italy). Mann-Whitney U test was used to compare knee OA patients with the healthy individuals.ResultsThe age (p=0.189) and BMI (p=0.367) were comparable between groups. The muscle architectural characteristics of RF, VM, PL and MG were different between groups (Table1). The distribution of foot pressure parameters were altered in knee OA patients compared to healthy controls (Table1).ConclusionThe fat thickness of ankle and knee muscles were higher in knee OA patients compared to healthy controls. Clinicians should consider adding aerobic and resistance exercises to their treatment programs that will increase muscle thickness and decrease fat thickness. The medial load of the foot increased while the lateral load decrease in these patients. Medial supported insoles may be recommended to reduce the medial load on the foot.References[1] Aily JB, de Noronha M, de Almeida AC, et al. Evaluation of vastus lateralis architecture and strength of knee extensors in middle-aged and older individuals with knee osteoarthritis. Clin Rheumatol. 2019;38(9):2603-2611.[2] Karapinar M, Ayyildiz VA, Unal M, Firat T. Effect of intramuscular fat in the thigh muscles on muscle architecture and physical performance in the middle-aged women with knee osteoarthritis. J Orthop Sci. 2022; S0949-2658(22)00324-4Table 1.Muscle architectural characteristics and foot pressure distribution among the groupsParametersOA Group (n=20)median (IQR)Healthy Group (n=20)median (IQR)pRFFat thickness (cm)1.4 (1-2.2)1.05 (0,6-1.5)0.001*Muscle thickness (cm)1.8 (1.3-2.8)2 (1.5-2.9)0.211Pennation angle (°)12 (8.7-18.2)12.8 (10.3-17.5)0.341VMFat thickness (cm)1.4 (0.8-2.1)0.9 (0.6-1.8)0.001*Muscle thickness (cm)1.7 (1.4-2.8)1.9 (1.3-2.6)0.048*Pennation angle (°)11.6 (7.2-16.9)13.4 (10.1-19.6)0.046*PLMuscle thickness (cm)0.8 (0.6-1.1)1 (0.6-1.3)0.007*Pennation angle (°)11.1(7.2-15.7)10.6 (8.6-16.6)0.296MGFat thickness (cm)1 (0.7-1.6)0.8 (0.6-1.6)0.005*Muscle thickness (cm)1.8 (1.3-2.5)1.9 (1.2-2.4)0.398Pennation angle (°)20.6 (15.2-23.3)21.6 (17.8-28.2)0.221FootPressureDistributionTotal surface area (cm2)265.2 (186-331.2)224.1 (143.2-350)0.050Total load (kg)39.7 (25.2-52)32.2 (22.4-62)0.009*Medial load (kg)18.3 (12.8-25.8)15.6 (11.3-31.5)0.009*Lateral load (kg)16.6 (12.3-28)20.6 (11.1-30.5)0.008*Foot angle (°)8.1 (2.6-16.7)10.5 (4.9-14.6)0.043*Foot progression angle(°)9.3 (0.7-27.9)11 (1.5-17.9)0.134OA: Osteoarthritis, RF: Rektus Femoris, VM: Vastus Medialis, PL: Peronalis longus, MG: Medial Gastrocnemius, IQR: interquartile range*p<0.05 Mann-Whitney U testAcknowledgements:NIL.Disclosure of InterestsNone Declared.

BackgroundSufficient lower extremity muscle mass is necessary for performing functional tasks. It is well known that body mass index (BMI) adversely effect knee cartilage health but in knees with osteoarthritis (OA) it is still unclear how BMI level effect knee muscle architectural characteristics.ObjectivesThe aim of this study was to investigate effect of body mass index (BMI) level on quadriceps muscle architecture in patients with knee OA and healthy controls.MethodsNineteen patients with OA (mean age= 50.58±4.56 years, mean BMI=28.29±2.51 kg/m2,) and twenty healthy controls (mean age= 48.35±2.83 years, mean BMI=26.76±4.88 kg/m2) were included in the study. Rectus Femoris (RF), Vastus Medialis (VM) and Vastus Lateralis (VL) muscles thickness and pennation angle were evaluated using B-Mode ultrasonography (Esaote MyLab X8 eXP Ultrasound System, Florence, Italy). Ultrasound images were analyzed offline using an image analysis software (Image J, National Institutes of Health, Bethesda, MD, USA) program. When investigating the changes in muscle architecture by group, the effect of BMI was adjusted using covariance analysis (ANCOVA) tests.ResultsThere were no differences between age (p=0.073) and BMI (p=0.10) in both groups. Interaction between groupXBMI represented in Table 1. Control group had higher RF muscle thickness, RF pennation angle, VM muscle thickness, VM pennation angle and VL muscle thickness than OA group. There was significant effect of BMI on VM and VL muscle thickness.ConclusionPatients with knee osteoarthritis has lower quadriceps muscle thickness and pennation angle than matched healthy controls and BMI was an important factor effecting muscle characteristics. The decrease in VM and VL muscle thickness were associated with increased BMI in knee OA group. These findings highlight the need of body weight control in order to restore muscle thickness in knee OA patients.References[1]Aily JB, de Noronha M, de Almeida AC, et al. Evaluation of vastus lateralis architecture and strength of knee extensors in middle-aged and older individuals with knee osteoarthritis. Clin Rheumatol. 2019;38(9):2603-2611.[2]Keng A, Sayre EC, Guermazi A, Nicolaou S, Esdaile JM, Thorne A, Singer J, Kopec JA, Cibere J. Association of body mass index with knee cartilage damage in an asymptomatic population-based study. BMC Musculoskelet Disord. 2017 Dec 8;18(1):517. doi: 10.1186/s12891-017-1884-7.Table 1.Muscle architectural characteristics of the groups and interaction between group and BMI.ParametersOA Group (n=19, 27 knees)mean (SD)Healthy Group (n=20, 39 knees)mean (SD)Group effectpBMI effectpRFMuscle thickness (cm)1.78±0.351.99±0.300.0060.153Pennation angle (°)11.76±3.6313.71±2.290.0080.444VMMuscle thickness (cm)1.6±0.371.88±0.28<0.0010.032*Pennation angle (°)10.08±3.6213.05±2.7<0.0010.889VLMuscle thickness (cm)1.84±0.52.05±0.330.0140.032*Pennation angle (°)15.85± 2.9615.71±2.830.8990.770OA: Osteoarthritis, RF: Rektus Femoris, VM: Vastus Medialis, VL: Vastus Lateralis, SD: Standard Deviation*p<0.05 Significant effect of BMI on groups.Acknowledgements:NIL.Disclosure of InterestsNone Declared.