{
  "abstract": "Introduction Systemic sclerosis (SSc) is characterized by generalized vasculopathy, autoimmune inflammation, fibrosis, and impairment of the internal organs additionally the musculoskeletal system. The distal muscles and the hand functions are frequently deteriorated; however, the muscles around the trunk are also affected. Decreased proximal muscle strength may reduce patients’ endurance and quality of life. We studied changes in muscle strength over a period of five years and its correlation with relevant clinical parameters.Material and Methods We examined 160 patients (88 diffuse, 72 limited cutaneous SSc; 138 females, 22 males; mean age 55.8±13.1 years) and 62 healthy controls (mean age 57.1±13.2 years). Manual Muscle Test 8 (MMT8), grip strength, and pinch strength were measured. Results of spirometry, echocardiography, six-minute walk test (6MWT), the Health Assessment Questionnaire Disability Index (HAQ-DI) and the Short Form-36 Mental and Physical Component Summary (SF-36 MCS and PCS) were also analysed.Results Both peripheral and proximal muscle strength were significantly reduced compared to healthy subjects. According to the MMT8 (0–10), in SSc patients the lowest scores were observed for the gluteus maximus, gluteus medius, and cervical flexor muscles, with median/interquartile ranges of 7/2, respectively. There was a significant difference in muscle strength between patients with early (<4 years) and late (>4 years) disease duration as measured by MMT-8 in the deltoid, biceps brachii and quadriceps muscles. Late-stage SSc patients showed significantly worse results (p<0.05).Both the total MMT8 score and the individual muscle scores showed strong positive correlations with the 6MWT, SF-36 PCS results, while showing a negative correlation with the left ventricular mass index, Cochin Hand Function Scale, the HAQ-DI and the Visual analogue score-Fatigue.During the five-year follow-up period, we observed significant improvements in pinch, grip, and biceps muscle strength in patients with the shorter disease duration. In late cases, also some improvements were measured in grip, pinch strength, and in the biceps, while deterioration was observed in quadriceps femoris and ankle dorsiflexors based on MMT8.Conclusions Muscle strength is significantly reduced in patients with SSc compared to healthy individuals. Proximal muscle strength loss is also detectable in early-onset patients and is closely associated with patients’ reduced endurance and physical condition. During the 5-year follow-up, no significant generalized muscle strength deterioration was observed in patients with SSc, except for reduced strength in two lower limb muscle groups in late-stage cases. From a therapeutic point of view, preventing early muscle strength loss would be essential.",
  "authors": [
    {
      "affiliations": [
        "Department of Rheumatology and Immunology, Medical School, University of Pécs, Pécs, Hungary"
      ],
      "name": "Antónia Nikolett Ács"
    },
    {
      "affiliations": [
        "Department of Rheumatology and Immunology, Medical School, University of Pécs, Pécs, Hungary"
      ],
      "name": "Máté Palancsa"
    },
    {
      "affiliations": [
        "Department of Rheumatology and Immunology, Medical School, University of Pécs, Pécs, Hungary"
      ],
      "name": "Zsófia Bálint"
    },
    {
      "affiliations": [
        "Department of Rheumatology and Immunology, Medical School, University of Pécs, Pécs, Hungary"
      ],
      "name": "Franciska Kiss"
    },
    {
      "affiliations": [
        "Department of Rheumatology and Immunology, Medical School, University of Pécs, Pécs, Hungary"
      ],
      "name": "Cecília Varjú"
    }
  ],
  "title": "P.326 Muscle involvement in systemic sclerosis",
  "uid": "0455d68b-39d6-5dc3-8f20-d3be027b9d50"
}