Arthroscopic osteoplasty of the medial and anteromedial wall of temporomandibular joint: surgical technique and anatomical considerations.

The anterior displacement of the articular disc is the most frequent cause of pathological alterations in the TMJ. Although it is an extremely common pathology, there is no certainty about the aetiopathogenesis of this disease. The main aim of the present report is to describe new anatomical findings that could help clarifying the aetiopathogenesis of this disease and determine a typology of treatment based on the cause of the disease. All the operative records of patients who underwent arthroscopic osteoplasty of the medial TMJ wall in our centre from January 2021 to September 2021 were reviewed and analysed to identify specific anatomical features observed in every procedure. Fifty-two joints were included for analysis in this study. Twenty-two joints were classified as Wilkes stages II-III and 30 as Wilkes stages IV-V. The most common complication observed in our sample was the dysaesthesias found in the temporal and preauricular regions. Other complications observed were frontal branch paresis (n = 2), intraoperative bleeding (n = 1), and postoperative malocclusion (n = 1). The compression of the superior head of pterygoid lateral muscle (SPLM) on the medial bony wall and the consequent muscle atrophy could be key for the aetiology of the anterior TMJ disc displacement. Therapeutic actions on the osseous and muscular component in this anatomical area could improve the outcomes of patients affected by TMJ internal derangement. A meticulous dissection of the fascia of the superior fascicle of the lateral pterygoid muscle allows a remodelling of the bone surfaces with minimal complications.

Ultrasound imaging evaluation of structural and textural features in asymptomatic achilles tendons in pre-professional dancers: A cross-sectional study.

OBJECTIVE: To evaluate performance descriptors, sociodemographics variables and tendon echogenicity of asymptomatic Achilles tendons and to compare the echotexture from different classification subgroups. DESIGN: A prospective, randomized cross-sectional study was carried out. SETTING: laboratory of university. PARTICIPANTS: Forty-two Achilles tendons (AT) were recruited from pre-professional dancers. Based on the echogenicity pattern, the sample was divided into two groups (n = 21, Heterogeneous group; n = 21, Homogeneous group). MAIN OUTOCOME MEASURES: Ultrasound images and ImageJ measurements were performed to evaluate thickness (AT-TH), echointensity (EI) and echovariation (EV), in addition to a balance and endurance test were measured as performance parameter. RESULTS: EI (p = 0.001) and EV (p = 0.001) reported statistically significant differences between groups. AT-TH, endurance test, balance test, years of dance, training hours per week and average pointe hours per week did not showed differences between groups. A multivariate prediction model between groups and the echotexture variables (EI (R2 = 0.569; EV (R2 = 0.341)) were determined. CONCLUSION: Asymptomatic AT of heterogeneous group showed a lower EI and a higher EV compared to homogeneous group. Tendon echogenicity did not interact with performance variables.

Cross-Cultural Adaptation of the Dance Functional Outcome Survey (DFOS) for Spanish Dancers.

A growing number of research papers regarding Spanish-speaking dancers justifies the need for an adapted Spanish version of the Dance Functional Outcome Survey (DFOS). The objective of this study was to cross-culturally adapt and validate the DFOS for Spanish-speaking dancers. A sample of 127 healthy and injured professional and pre-professional dancers were recruited. Test-retest reliability of DFOS-Sp was examined using intraclass correlation coefficients. Construct validity compared DFOS-Sp to the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) using Pearson correlations. Principal component analysis identified factors and internal-item consistency. Sensitivity was evaluated by generating receiver operating characteristic and area under the curve analyses. A subgroup of 51 injured dancers were followed across three time-points to examine responsiveness using repeated measures analysis of variance. Injured scores were analyzed for floor and ceiling effects. The DFOS-Sp showed high test-retest reliability (ICC2,1 ≥ 0.92). DFOS-Sp scores had moderate construct validity compared with SF-36 physical component summary scores (r ≥ 0.56). Principal component analysis (PCA) supported uni-dimensionality explaining 58% of the variance with high internal consistency (α = 0.91).Area under the curve (AUC) sensitivity values were excellent (AUC ≥ 0.82). There were significant differences across time (p < 0.001), demonstrating responsiveness to change, with no floor or ceiling effects. The DFOS-Sp demonstrated acceptable test-retest reliability and validity in Spanish-speaking dancers, with comparable psychometric performance to the English-language version.

Does Function Determine the Structure? Changes in Flexor Hallucis Longus Muscle and the Associated Performance Related to Dance Modality: A Cross-Sectional Study.

Background and Objectives: Flexor hallucis longus pathology is one of the most common conditions of the ankle and foot in dancers, due to the high demand of dance movements performed in an extreme plantar flexion and dorsiflexion range of motion. The objectives of this study were to determine the bilateral differences between the thickness and cross-sectional area of the flexor hallucis longus muscle in dancers, to establish possible differences between dance modalities, and to analyze whether there is a correlation between ultrasonographic parameters or performance variables and the dance modality. Material and Methods: A sample of 50 (29 classical and 21 contemporary) full-time pre-professional female dancers were included in the study. The thickness and cross-sectional area of the flexor hallucis longus muscle were evaluated for both limbs using ultrasound imaging. The range of movement of the first metatarsophalangeal joint was measured using functional extension with maximal ankle plantarflexion, balance was measured in a unilateral stance with the heel raised, endurance was evaluated through a modified heel rise fatigue test, and a counter movement jump to assess the vertical jump performance was measured bilaterally. Results: There were no significant differences recorded between the dominant and non-dominant limbs for each variable, within both groups. Contemporary dancers showed a greater thickness and cross-sectional area of the flexor hallucis longus muscle than classical dancers. However, classical dancers showed an increase of balance, endurance, range of movement of the first metatarsophalangeal joint, and counter movement jump with respect to contemporary dancers. Conclusion: Bilateral symmetry was identified in all variables for both groups. The size and performance of the flexor hallucis longus muscle may be influenced by the specific nature of dance modality.

Ultrasound imaging features of the Achilles tendon in dancers. Is there a correlation between the imaging and clinical findings? A cross-sectional study.

OBJECTIVES: To analyze the prevalence of tendon pathology and performance associated in pre-professional classic dancers with no history of Achilles tendon (AT) pain. DESIGN: A cross-sectional study was conducted. PARTICIPANTS: Twenty-nine classic ballet dancers without AT pain (58 tendons) were recruited. The tendons were classified (normal, abnormal) using ultrasound imaging (USI). Cross-sectional area (CSA) and thickness of flexor hallucis longus (FHL) muscle were measured using USI. Range of movement (ROM) of the first metatarsophalangeal join, balance test, endurance test and vertical jump were measured (bilaterally) as performance variables. RESULTS: More than a half (62%) of the participants had at least one abnormal tendon, with 45% of the dancers in the abnormal group having bilateral abnormalities. Dancers with AT pathology had significantly more years of dancing and number of weekly pointe hours than those with no pathology on US imaging. No significant differences between the groups were identified for the rest of the variables. Dancing years were moderately correlated with AT thickness. CONCLUSIONS: Asymptomatic classic dancers had a high incidence of tendon pathology. Increased dancing years was associated with pathology in the AT. Nevertheless, these abnormalities may not affect dance performance.

Comparative Effects of One-Shot Electrical Stimulation on Performance of the Flexor Hallucis Longus Muscle in Professional Dancers: Percutaneous Versus Transcutaneous?

OBJECTIVE: High demand of flexor hallucis longus (FHL) in the positions of extreme flexion of the ankle and toes is required in the dance. The aim was to investigate the effects of single-shot of ultrasound-guided percutaneous neuromodulation (PNM) vs. single-shot of transcutaneous electrical nerve stimulation (TENS) in performance of the FHL muscle in professional dancers. MATERIALS AND METHODS: Thirty-two female healthy dancers were divided into two groups: TENS group and PNM group. The stimulation interventions consisted in the application of a square wave biphasic electrical current for a total of 1.5 mins. Range of motion (ROM) of first metatarsophalangeal joint, balance test, and unilateral heel raise fatigue test were performed in dominance limb. RESULTS: There were no differences between both groups in the baseline measurements. Compared to their baseline values, the TENS group statistically improved balance (p < 0.01, d = 0.6), ROM (p < 0.001, d = 0.3), and endurance (p = 0.04, d = 0.5). The PNM group only statistically improved balance and endurance (p < 0.001), with a large effect size for both test (d = 0.8 and d = 2.24, respectively). After interventions, there were no significant differences between TENS and PNM groups for all variables. However, PNM was qualitatively more effective because the percentage change in mean was greater and effect size was large for the balance test and endurance test. CONCLUSIONS: Simple single-shot procedure with percutaneous or TENS provided immediate performance improvement of FHL muscle in dancers, being PNM the more effective intervention.

Immediate effects of ultrasound-guided percutaneous neuromodulation versus physical exercise on performance of the flexor hallucis longus muscle in professional dancers: a randomised clinical trial.

BACKGROUND: Ultrasound-guided percutaneous neuromodulation (US-guided PNM) is a minimally invasive intervention. This technique consists of the application of percutaneous electrical stimulation (PES) through an acupuncture needle-like electrode that is placed in close proximity to the nerve or motor point of the target muscle under ultrasound guidance. OBJECTIVE: To examine the immediate effects of a stretching exercise, an eccentric exercise and US-guided PNM on the performance of the flexor hallucis longus (FHL) muscle in young dancers. METHODS: Randomised clinical trial. A total of 45 dancers were divided into three groups: Stretching group, Eccentric group and PNM group. The following performance parameters were assessed: range of motion (ROM) of the first metatarsophalangeal joint, balance test and unilateral heel raise fatigue test. RESULTS: There were no differences between these groups in baseline measurements; at the end of the study, mean balance and endurance values were only significantly higher for the PNM group compared to the Stretching (p = 0.007 and p < 0.001, respectively) and Eccentric groups (p = 0.003 and p < 0.001, respectively). The effect sizes were large for the balance (d = 0.8) and endurance (d = 1.83) tests in the PNM group. Both the Stretching and Eccentric groups exhibited improvements in ROM compared to their baseline values (p = 0.009 and p = 0.004, respectively), whereas there was no significant temporal improvement noted for the PNM group. The effect sizes with respect to ROM values were moderate for stretching (d = 0.6) and eccentric (d = 0.7) exercises. CONCLUSION: An isolated PES intervention provides a greater immediate increase in balance and muscular strength than an active stretching and eccentric exercise of the FHL muscle in young ballet dancers.