Reliability of measuring pectoralis minor muscle resting length in subjects with and without signs of shoulder impingement

Background: Pectoralis minor adaptive shortening may change scapula resting position and scapular kinematics during arm elevation. A reliable and clinically feasible method for measuring pectoralis minor length will be useful for clinical decision making when evaluating and treating individuals with shoulder pain and dysfunction. Objectives: To evaluate intrarater, interrater, and between-day reliability of a pectoralis minor (PM) muscle length measurement in subjects with and without signs of shoulder impingement. Method: A convenience sample of 100 individuals (50 asymptomatic and 50 symptomatic) participated in this study. Intra- and interrater reliability of the measurement was estimated in 50 individuals (25 asymptomatic and 25 symptomatic), and between-day reliability of the measurement repeated over an interval of 7 days was estimated in an independent sample of 50 additional participants. Pectoralis minor length was measured using a flexible tape measure with subjects standing. Results: Intraclass correlation coefficients (ICC3,k) for intrarater and interrater reliability ranged from 0.86-0.97 and 0.95 for between-day reliability in both groups. Standard error of measurements (SEM) ranged from 0.30-0.42 cm, 0.70-0.84 cm, and 0.40-0.41 cm for intrarater, interrater, and between-day reliability, respectively, across the sample. The minimal detectable change (MDC) for between-day measurements ranged from 1.13-1.14 cm for both groups. Conclusions: In asymptomatic individuals and in those with signs of shoulder impingement, a single rater or pair of raters can measure pectoralis minor muscle length using a tape measure with very good reliability. This measurement can also be reliably used by the same rater over a seven day interval.

Eccentric training for shoulder abductors improves pain, function and isokinetic performance in subjects with shoulder impingement syndrome: a case series / Treino excêntrico para abdutores do ombro melhora dor, função e desempenho isocinético em sujeitos com síndrome do impacto: série de casos

BACKGROUND: Conservative treatments have been proposed for people with shoulder impingement syndrome (SIS), such as strengthening of the rotator cuff and scapular muscles and stretching of the soft tissues of the shoulder. However, there is a lack of studies analyzing the effectiveness of eccentric training in the treatment of SIS. OBJECTIVES: To evaluate the effects of eccentric training for shoulder abductors on pain, function, and isokinetic performance during concentric and eccentric abduction of the shoulder in subjects with SIS. METHODS: Twenty subjects (7 females, 34.2 SD 10.2 years, 1.7 SD 0.1 m, 78.0 SD 16.3 kg) with unilateral SIS completed the study protocol. Bilateral isokinetic eccentric training at 60º/s for shoulder abductors was performed for six consecutive weeks, twice a week, on alternate days. For each training day, three sets of 10 repetitions were performed with a 3-minute rest period between the sets for each side. The range of motion trained was 60° (ranging from 80° to 20°). The Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire was used to evaluate functional status and symptoms of the upper limbs. Peak torque, total work and acceleration time were measured during concentric and eccentric abduction of the arm at 60º/s and 180º/s using an isokinetic dynamometer. RESULTS: DASH scores, peak torque, total work and acceleration time improved (p<0.05) after the period of intervention. CONCLUSIONS: This study suggests that isokinetic eccentric training for shoulder abductors improves physical function of the upper limbs in subjects with SIS.

CONTEXTUALIZAÇÃO: Tratamentos conservadores têm sido propostos para pessoas com síndrome do impacto (SI) do ombro, como fortalecimento do manguito rotador e dos músculos escapulares e alongamento dos tecidos moles do ombro. No entanto, são escassos os estudos que analisaram a eficácia do treinamento excêntrico no tratamento da SI. OBJETIVOS: Avaliar os efeitos do treinamento excêntrico para abdutores do ombro na dor, função e desempenho isocinético durante a abdução concêntrica e excêntrica do ombro em indivíduos com SI. MÉTODOS: Vinte indivíduos (sete mulheres, 34,2 DP 10,2 anos, 1,7 DP 0,1 m, 78,0 DP 16,3 kg) com SI unilateral completaram o protocolo do estudo. Realizou-se treinamento isocinético excêntrico bilateral a 60º/s para abdutores do ombro durante seis semanas consecutivas, duas vezes por semana, em dias alternados. Para cada dia de treinamento, foram realizadas três séries de dez repetições, com um período de descanso de 3 minutos entre as séries para cada lado. A amplitude de movimento treinada foi de 60° (de 80° a 20°). O questionário Disabilities of the Arm, Shoulder and Hand (DASH) foi utilizado para avaliar a função e os sintomas dos membros superiores. O pico de torque, o trabalho total e o tempo de aceleração foram avaliados durante a abdução concêntrica e excêntrica do braço a 60º/s e 180º/s por meio de um dinamômetro isocinético. RESULTADOS: As pontuações do DASH, o pico de torque, o trabalho total e o tempo de aceleração melhoraram (p<0,05) após o período de intervenção. CONCLUSÕES: Este estudo sugere que o treinamento isocinético excêntrico para abdutores do ombro melhora a função física dos membros superiores em indivíduos com SI.

The effects of knee extensor eccentric training on functional tests in healthy subjects / Os efeitos do treino isocinético excêntrico dos extensores do joelho nos testes funcionais em sujeitos saudáveis

BACKGROUND: It is well known that eccentric training increases muscle strength and promotes greater neural activation, and therefore has been used in the recovery of knee extensors. The hypothesis of this study was that there would be a strong correlation between knee extensor torque and functional tests. OBJECTIVES: To investigate the relationship between knee extensor peak torque and functional tests of agility (runs) and propulsion (hop for distance) after short-term isokinetic eccentric training. METHODS: Twenty healthy and active male undergraduate students (age 22.5±2.1 years; height 1.72±0.10 m; weight 67.8±9.5 kg; body mass index: 22.5±2.0 kg/m²), with no abnormalities or history of injury of the limbs, performed an isokinetic assessment of the knee extensors and flexors and also functional tests before and after isokinetic training, which consisted of 3 sets of 10 MVECs at 30º/s, with 3 minutes of rest between sets, twice a week for 6 weeks. RESULTS: The eccentric training increased the extensor peak torque (16, 27 and 17 percent; P<0.01) and decreased the H/Q ratio (10, 20 and 13 percent; P<0.01) for the isometric and eccentric modes at 30°/s and 120°/s, respectively. It also decreased the time in two of the five agility tests (carioca and pivot diagonal; P<0.01), and increased the distance in the hop tests, for both dominant and non-dominant limbs (P<0.01). CONCLUSIONS: Although the eccentric training led to an increase in extensor peak torques as well as an improvement in most of the functional tests, the hypothesis that a strong correlation would be observed between peak torques and functional tests was not confirmed. Article registered in the Australian New Zealand Clinical Trials Registry (ANZCTR) under the number 12607000590460.

CONTEXTUALIZAÇÃO: Sabe-se que o treino excêntrico aumenta a força muscular, promovendo uma maior ativação neural e, portanto, tem sido usado na recuperação do torque extensor. A hipótese deste estudo foi a de que possa existir uma forte correlação entre o torque extensor do joelho e os testes funcionais. OBJETIVOS: Correlacionar o torque extensor do joelho com os testes funcionais de agilidade (corridas) e impulsão (saltos em distância) após o treino isocinético excêntrico de curta duração. MÉTODOS: Vinte homens universitários, ativos e saudáveis (22,5±2,1 anos; 1,72±0,10 m; 67,8±9,5 kg; IMC 22,5±2,0 kg/m²), sem reportar anormalidades ou história de lesão no membro inferior, realizaram avaliação isocinética do torque extensor e flexor do joelho e testes funcionais antes e depois do treino isocinético que consistiu em três séries de 10 CEVM a 30º/s, com 3 minutos de repouso entre as séries, realizado duas vezes por semana, durante seis semanas. RESULTADOS: O torque extensor aumentou (16, 27 e 17 por cento; P<0,01), a razão I/Q diminuiu (10, 20 e 13 por cento; p<0,01) para os modos: isométrico e excêntrico a 30°/s e 120°/s, respectivamente; diminuiu o tempo em dois dos cinco testes de corridas (carioca e pivô diagonal; P<0,01) e aumentou a distância nos testes de saltos tanto para o membro dominante quanto para o não dominante (P<0,01). CONCLUSÕES: Embora o treino excêntrico tenha aumentado o torque dos extensores do joelho, bem como melhorado a maioria dos testes funcionais, a hipótese de uma forte correlação entre essas variáveis não se confirmou. Artigo registrado no Australian New Zealand Clinical Trials Registry (ANZCTR) sob o número 12607000590460.