An overlooked rheumatologic manifestation of diabetes: diabetic cheiroarthropathy

Ultrasonographic findings in diabetic cheiroarthropathy: a pilot study

OBJECTIVE

Diabetic cheiroarthropathy (DCA) is one of the musculoskeletal manifestations of diabetes mellitus. It is clinically diagnosed using the prayer and tabletop signs. The clinical appearance, however, mimics autoimmune-mediated polyarthritis of the hands and fingers. It is therefore crucial to positively identify DCA patients.

METHOD

We used high-frequency B-mode ultrasound to investigate 14 patients with DCA and seven non-DCA diabetics with anti-cyclic citrullinated peptide antibody-positive rheumatoid arthritis (RA). We recorded the frequency of synovitis in radiocarpal, metacarpophalangeal, and proximal interphalangeal joints, the presence of tenosynovitis of the finger flexor tendons, echogenicity of the synovia and the flexor tendon sheaths, and soft tissue alterations in the digits. We compared our findings between groups to determine sonographic characteristics of DCA.

RESULTS

A low rate of small finger joint involvement in the presence of a high rate of finger flexor tendinopathy showed a high association with DCA in correlation (p = 0.002) and regression analysis (p < 0.001). Tendon sheaths were significantly more often hyperechoic and proliferative in DCA compared to RA (p = 0.008), and hypoechoic soft tissue alterations were almost exclusively seen in DCA patients (p = 0.003). Radiocarpal joint involvement and its echogenicity did not differ between groups.

CONCLUSION

Ultrasonography shows typical features in DCA, and is capable of discriminating DCA from non-DCA patients with RA and diabetes.

Hyperglycaemia is a causal risk factor for upper limb pathologies

BACKGROUND

Diabetes (regardless of type) and obesity are associated with a range of musculoskeletal disorders. The causal mechanisms driving these associations are unknown for many upper limb pathologies. We used genetic techniques to test the causal link between glycemia, obesity and musculoskeletal conditions.

METHODS

In the UK Biobank's unrelated European cohort (N = 379 708) we performed mendelian randomisation (MR) analyses to test for a causal effect of long-term high glycaemia and adiposity on four musculoskeletal pathologies: frozen shoulder, Dupuytren's disease, carpal tunnel syndrome and trigger finger. We also performed single-gene MR using rare variants in the GCK gene.

RESULTS

Using MR, we found evidence that long-term high glycaemia has a causal role in the aetiology of upper limb conditions. A 10-mmol/mol increase in genetically predicted haemoglobin A1C (HbA1c) was associated with frozen shoulder: odds ratio (OR) = 1.50 [95% confidence interval (CI), 1.20-1.88], Dupuytren's disease: OR = 1.17 (95% CI, 1.01-1.35), trigger finger: OR = 1.30 (95% CI, 1.09-1.55) and carpal tunnel syndrome: OR = 1.20 (95% CI, 1.09-1.33). Carriers of GCK mutations have increased odds of frozen shoulder: OR = 7.16 (95% CI, 2.93-17.51) and carpal tunnel syndrome: OR = 2.86 (95% CI, 1.50-5.44) but not Dupuytren's disease or trigger finger. We found evidence that an increase in genetically predicted body mass index (BMI) of 5 kg/m2 was associated with carpal tunnel syndrome: OR = 1.13 (95% CI, 1.10-1.16) and associated negatively with Dupuytren's disease: OR = 0.94 (95% CI, 0.90-0.98), but no evidence of association with frozen shoulder or trigger finger. Trigger finger (OR 1.96 (95% CI, 1.42-2.69) P = 3.6e-05) and carpal tunnel syndrome [OR 1.63 (95% CI, 1.36-1.95) P = 8.5e-08] are associated with genetically predicted unfavourable adiposity increase of one standard deviation of body fat.

CONCLUSIONS

Our study consistently demonstrates a causal role of long-term high glycaemia in the aetiology of upper limb musculoskeletal conditions. Clinicians treating diabetes patients should be aware of these complications in clinic, specifically those managing the care of GCK mutation carriers. Upper limb musculoskeletal conditions should be considered diabetes complications.

Quantification of joint mobility limitation in adult type 1 diabetes

Aims

Diabetic cheiroarthropathies limit hand mobility due to fibrosis and could be markers of a global profibrotic trajectory. Heterogeneity in definitions and lack of a method to measure it complicate studying associations with organ involvement and treatment outcomes. We measured metacarpophalangeal (MCP) joint extension as a metric and describe magnetic resonance (MR) imaging determinants of MCP restriction.

Methods

Adults with type 1 diabetes were screened for hand manifestations using a symptom questionnaire, clinical examination, and function [Duruoz hand index (DHI) and grip strength]. Patients were segregated by mean MCP extension (<20°, 20°-40°, 40°-60°, and >60°) for MR imaging (MRI) scanning. Patients in the four groups were compared using ANOVA for clinical features and MRI tissue measurements (tenosynovial, skin, and fascia thickness). We performed multiple linear regression for determinants of MCP extension.

Results

Of the 237 patients (90 men), 79 (33.8%) with cheiroarthropathy had MCP extension limitation (39° versus 61°, p < 0.01). Groups with limited MCP extension had higher DHI (1.9 vs. 0.2) but few (7%) had pain. Height, systolic blood pressure, and nephropathy were associated with mean MCP extension. Hand MRI (n = 61) showed flexor tenosynovitis in four patients and median neuritis in one patient. Groups with MCP mobility restriction had the thickest palmar skin; tendon thickness or median nerve area did not differ. Only mean palmar skin thickness was associated with MCP extension angle on multiple linear regression.

Conclusion

Joint mobility limitation was quantified by restricted mean MCP extension and had structural correlates on MRI. These can serve as quantitative measures for future associative and interventional studies.

Does hand stiffness reflect internal organ fibrosis in diabetes mellitus?

Fibrosis leads to irreversible stiffening of tissue and loss of function, and is a common pathway leading to morbidity and mortality in chronic disease. Diabetes mellitus (both type 1 and type 2 diabetes) are associated with significant fibrosis in internal organs, chiefly the kidney and heart, but also lung, liver and adipose tissue. Diabetes is also associated with the diabetic cheirarthropathies, a collection of clinical manifestations affecting the hand that include limited joint mobility (LJM), flexor tenosynovitis, Duypuytren disease and carpal tunnel syndrome. Histo-morphologically these are profibrotic conditions affecting various soft tissue components in the hand. We hypothesize that these hand manifestations reflect a systemic profibrotic state, and are potential clinical biomarkers of current or future internal organ fibrosis. Epidemiologically, there is evidence that fibrosis in one organ associates with fibrosis with another; the putative exposures that lead to fibrosis in diabetes (advanced glycation end product deposition, microvascular disease and hypoxia, persistent innate inflammation) are 'systemic'; a common genetic susceptibility to fibrosis has also been hinted at. These data suggest that a subset of the diabetic population is susceptible to multi-organ fibrosis. The hand is an attractive biomarker to clinically detect this susceptibility, owing to its accessibility to physical examination and exposure to repeated mechanical stresses. Testing the hypothesis has a few pre-requisites: being able to measure hand fibrosis in the hand, using clinical scores or imaging based scores, which will facilitate looking for associations with internal organ fibrosis using validated methodologies for each. Longitudinal studies would be essential in delineating fibrosis trajectories in those with hand manifestations. Since therapies reversing fibrosis are few, the onus lies on identification of a susceptible subset for preventative measures. If systematically validated, clinical hand examination could provide a low-cost, universally accessible and easily reproducible screening step in selecting patients for clinical trials for fibrosis in diabetes.

What Is the Diagnosis in Patients with Type 2 Diabetes Who Have a Painful Shoulder? Results from a Prospective Cross-Sectional Study

Background: Patients with diabetes mellitus have higher risk of developing shoulder pathology. However, only adhesive capsulitis is addressed in shoulder pain guidelines as a disorder associated with diabetes. Yet, patients with diabetes are at risk of having several other shoulder disorders, including focal neuropathy. Our aim was to quantify the presence of shoulder disorders using physical examination and ultrasound imaging in patients with type 2 diabetes (T2DM) suffering from shoulder pain in general practice. Methods: In this prospective cross-sectional study, patients with T2DM who had had a painful shoulder for at least four weeks were included. Patients filled out a questionnaire and underwent a physical examination of the shoulders and feet and ultrasound imaging of the shoulder. Results: A total of 66 patients were included, of whom 40.9% (n = 27) had bilateral complaints resulting in 93 symptomatic shoulders. Subacromial pain syndrome was most frequently diagnosed by physical examination (66.6%, 95% CI 51.6–72.0%; p < 0.0001), while ultrasound imaging showed that subacromial disorders were statistically significantly the most prevalent (90.3%, 95% CI 81.9–95.2%). Only two patients (3%) were diagnosed with neuropathic shoulder pain. Conclusion: When choosing treatment, general practitioners should be aware that in patients with T2DM the subacromial region is most frequently affected.