Tendons, Joints, and Bone

Abstract

While tethering of the skin is the clinical hallmark of SSc, many patients may develop musculoskeletal symptoms as an early sign of the disease (up to 20 % of patients with SSc report joint symptoms as early as 1 year or more prior to diagnosis and a third within the same year of diagnosis) and/or during the course of their illness (Baron et al., Ann Rheum Dis 41:147–152, 1982). Manifestations may include varying degrees of rheumatic complaints ranging from carpal tunnel syndrome and arthralgia to frank inflammatory arthritis or bony lesions. Joint symptoms have been reported to be present in 66 % of patients with SSc and muscular symptoms in half of the patients, the latter with a predominance of muscle weakness and myalgia (Hietaharju et al., Muscle Nerve 16:1204–1212, 1993). Musculoskeletal involvement has been shown to strongly contribute to disability and impaired quality of life in SSc, reducing the performance of everyday occupation (Baron et al., Ann Rheum Dis 41:147–152, 1982; Mau et al., J Rheumatol 32:721–728, 2005; Brower and Poole, Arthritis Rheum 51:805–809, 2004; Poole et al., Arthritis Care Res 13:69–73, 2000; Poole and Steen, Arthritis Care Res 4:27–31, 1991). Indeed, several cross-sectional studies have been reported over the recent years all highlighting the major impact of musculoskeletal involvement on the quality of life in SSc. One report examined patients’ beliefs and investigated the relationship between these beliefs, symptom reports, and clinical/demographic variables. This study included a total of 49 patients (7 males, 42 females) who underwent clinical examination and completed the Revised Illness Perception Questionnaire. The symptoms patients most frequently associated with SSc were stiff joints (79 %), pain (75 %), and fatigue (75 %), all relating to musculoskeletal involvement. More than 96 % of patients believed that their condition would be chronic and 78 % believed that the condition had serious consequences on their lives. Patients with diffuse cutaneous SSc reported more significant consequences of the condition and less personal control of their SSc compared with patients with limited cutaneous disease (Richards et al., Arthritis Rheum 49:689–96, 2003). Another study focused on the ability to perform daily activities and analyzed in details hand function. Data from 30 patients showed that dexterity was on average reduced to 68–80 % and grip force to 46–65 % compared with values for healthy persons. Finger flexion and extension were the most impaired aspects of hand mobility. Activities building on hand and arm function were harder to perform than activities depending on lower limb function. Stiffness, grip force, and dexterity had the highest strength of association with difficulties of daily living activities after Raynaud’s phenomenon, which was the master symptom (Sandqvist et al., Scand J Rheumatol 33:102–107, 2004). A study focusing on impairment of hand function suggested that it could be similar or even higher than in rheumatoid arthritis or digital osteoarthritis: the authors showed the reliability and validity of Duruoz Hand Index in SSc and found a mean (SD) total score of 21.10 ± 19.25 (0–66), whereas mean scores of about 17 (SD) or 19 (SD) have been reported in series of patients with rheumatoid arthritis or osteoarthritis (Brower and Poole, Arthritis Rheum 51:805–809, 2004).