Diabetes is a known risk factor for carpal tunnel syndrome because diabetes induces structural changes in the connective tissues of tendons surrounding the median nerve, leading to nerve compression.12 Patients with diabetes have 90% higher odds of developing carpal tunnel syndrome and are more likely to have it in both wrists.13 In a cross-sectional study of 100 patients with diabetes, approximately 20% had carpal tunnel syndrome.14
Diagnosis and management of carpal tunnel syndrome is the same in patients with and without diabetes, although surgical release is more common in patients with diabetes.15 Carpal tunnel syndrome can coexist with diabetic polyneuropathy, thus it is important to establish whether peripheral nerve symptoms are secondary to nerve entrapment or diabetic polyneuropathy because patients with neuropathy may not sustain the same improvement after carpal tunnel release as those without polyneuropathy.16
Dupuytren’s contracture
Patients with Dupuytren’s contracture present with thickened, fibrotic nodules and cords within the palmar fascia leading to digital contractures, most commonly at the fourth and fifth digits.17 Dupuytren’s must be distinguished from diabetic cheiroarthropathy, which does not present with fibrotic nodules or cords, and tends to affect all digits but the thumb. Notably, the two can co-occur.
Dupuytren’s in patients with diabetes has been shown to occur four times more frequently than in those without it, and its prevalence is related to age and duration of diabetes.18
Diagnosis of Dupuytren’s is clinical. Patients who develop flexion contractures can undergo surgery (i.e., open fasciectomy), percutaneous needle aponeurotomy or collagenase injection. Surgery has been shown to have higher success rates at longer term follow-up.19
Stenosing flexor tenosynovitis
Stenosing flexor tenosynovitis, also known as trigger finger, is characterized by localized inflammation of the flexor tendon sheath, rather than the tenosynovium (as its name would suggest), leading to finger locking with failure of active extension. Patients may describe a painful popping or clicking sound when the digit is extended. With time, disuse of the digit can lead to secondary proximal interphalangeal contractures.20 The ring finger is most commonly affected, but multiple digits may be involved, and it can be bilateral.21
Trigger finger is more common in women, and estimated to occur at 5–11% in patients with diabetes, vs. 2–3% in the general population.22 The incidence in patients with diabetes is related to duration of diabetes, but not degree of diabetic control.18
First-line therapy includes splinting and corticosteroid injection, although the latter may be less successful in patients with diabetes, and success rates decline with every repeat injection.5,20 Surgical release is indicated if injection should fail.