DM: Stiff Joint Syndrome
Advanced, Organ-Based and Clinical Sciences
Stiff joint syndrome describes the triad of Type I diabetes mellitus, non-familial short stature, and stiff joints and/or joint contractures beginning approximately 10 years after diabetes onset1,2. Felt to be secondary to abnormal cross-linking of collagen3, Stiff Joint Syndrome predisposes a subset of type I diabetics to rapidly progressive microvascular disease and subsequent need for early renal and/or pancreas transplantation, regardless of blood glucose control or daily insulin requirements4. Additional symptoms include thickening of the skin2 and decreased lung elasticity5, resulting in decreased lung volumes.
Though it more commonly affects the 4th and 5th proximal phalangeal joints4, Stiff Joint Syndrome may manifest as atlanto-occipital joint stiffness as well6, making direct laryngoscopy significantly more difficult. Exposing the larynx often requires bringing the axes of the mouth, pharynx, and larynx into line, a feat typically requiring full neck extension at the atlanto-occipital joint to achieve. Should the occiput and atlas already contact in the neutral position, such as in severe stiff joint syndrome, no atlanto-occipital joint extension takes place, resulting in poor neck extension and anterior displacement of the larynx, worsening the view achieved with direct laryngoscopy7,8. In short, Diabetic Stiff Joint Syndrome increases the difficulty of direct laryngoscopy via increased atlanto-occipital joint stiffness, and preparations should be made ahead of attempting an airway in these patients requiring endotracheal intubation.