Most patients with osteoarthritis (OA) of the hand also showed inflammation and/or damage to hand tendons, a single-center study indicated.
Among 86 patients with hand OA, 70% showed involvement of at least one tendon with ultrasound examination, compared with 9% of a control group of age- and sex-matched controls with no hand complaints, according to Peter Mandl, MD, PhD, and colleagues at the Medical University of Vienna in Austria.
But the tendon involvement didn't appear to worsen patients' pain or function beyond that seen with uncomplicated hand OA, the researchers found.
Still, the group felt the finding had clinical relevance. "Physicians treating patients with [hand] OA should keep the high prevalence of tendon involvement in mind," they wrote in . "In case of clinical suspicion, a sonographic examination should be performed. If tenosynovitis or tendon damage is detected, treatment may be tailored accordingly." That, they acknowledged, isn't always an easy policy to follow.
The overall results both were and weren't as expected. As Mandl and colleagues explained, tenosynovitis -- "an inflammatory process affecting the synovial sheath of tendons" -- is a common feature of rheumatoid arthritis. Although it hadn't been well studied in association with OA, the disease "affects the entire joint, with various manifestations such as synovial hypertrophy, joint effusion, osteophytes, erosions, tendon damage and, in some cases, tendon rupture." What had been lacking was hard data on the prevalence of tendon involvement, as well as its impact on patient-centered outcomes.
For their study, Mandl's group enrolled 86 hand OA patients treated at the Medical University of Vienna, along with 23 people with no signs of the condition. Participants underwent ultrasound exams of their flexor and extensor tendons. Clinical exams to check for pain and functional impairment were also performed, and x-rays were taken as well. Patients completed questionnaires for their own evaluations of everyday pain and function.
Mean age was 66 for patients and 68 for controls. Some 87% of both groups were women. On a 10-point scale, the mean self-rated level of hand pain was 3.2 for patients and zero for controls.
Tenosynovitis was detected in 65% of patients and 9% of controls; damage was found in 16% of patients versus none of the controls. Radiographic data for osteophytes, joint space narrowing, and subchondral sclerosis also showed substantially more involvement in patients versus controls.
Yet there was little evidence that tendon inflammation and damage correlated with patients' ratings of pain or function. Values for the r correlation coefficient never exceed 0.12 for any comparison, and P values were all greater than 0.30.
Clinical exams in which a professional manipulated patients' hands, however, did indicate that tendon involvement correlated with increased pain and decreased function, with r values of 0.24-0.36 and P≤0.03.
"Considering that the clinical assessment of tendons is not standardized and more difficult compared to joint examination, our findings suggest that patients with tendon involvement might be identified by clinical examination, but accurate assignment to the respective tendon may not always be possible," Mandl and colleagues observed.
"Furthermore," they continued, "clinical examination might not differentiate between tendon involvement or other causes for pain. Pain, bony deformation, and loss of function, which are known characteristics of [hand] OA, likely all contribute to the difficulties facing clinical assessment, and prominent joint involvement may 'overshadow' concomitant tendon pathology." They suggested that imaging, particularly ultrasound, can help localize the source of clinical symptoms that can then lead to appropriate treatments.
Another caveat, the researchers noted, is that it remains unclear "whether tendon involvement develops only secondary to biomechanical factors (osteophytes) or whether it can be regarded as an independent inflammatory feature of [hand] OA" -- that's a question for future research, they said.
Disclosures
The city of Vienna funded the study. Several authors including Mandl reported extensive relationships with industry.
Primary Source
Rheumatology
Gessl I, et al "Tendon involvement and its association with pain and hand function in patients with osteoarthritis of the hand" Rheumatology 2024; DOI: 10.1093/rheumatology/keae395.