Prayer Sign and relation to difficult laryngoscopy.

Thickened waxy skin with joint contractures


This 30 year old juvenile onset insulin dependent diabetic developed diffuse subtle joint contractures of the hands with decreased ability to fully extend the fingers typical of limited joint mobility syndrome(LJM). Her skin was thickened and waxy especially on the tops of her hands. Skin biopsy showed increased dermal collagen. Cutaneous findings are postulated to result from accumulations of glycosylated proteins in the collagen matrix and fibroblast proliferation.

If patient shows inability to place palms flat together, it suggests difficult intubation. It is a reflection of generalised joint and cartilage immobility and tight waxy skin, particularly in diabetic patients. About 33% of diabetic patients are prone to difficult intubations. One study from Istanbul, Turkey compared 80 diabetic patients (D) with 80 non-diabetic patients (ND) undergoing elective surgery under general anaesthesia. The incidence of difficult laryngoscopy was 18.75% in Group D and 2.5% in Group ND. The incidence of the prayer sign was 31.25% in Group D and 13.75% in Group ND......

Relationship of difficult laryngoscopy to long-term non-insulin-dependent diabetes and hand abnormality:
About one-third of long-term insulin-dependent (type I) diabetics present with laryngoscopic difficulties.This is due, at least in part, to diabetic stiff joint syndrome characterized by a short stature, joint rigidity, and tight waxy skin.The fourth and fifth proximal phalangeal joints are most commonly involved. Patients with diabetic stiff joint syndrome have difficulty in approximating their palms and cannot bend their fingers backwards (the prayer sign).This is due to non enzymatic glycosylation of collagen and its deposition in joints. When the cervical spine is involved, limited atlanto-occipital joint motion may make laryngoscopy intubation difficult.

The incidence of difficult laryngoscopy was 18.75% in Group D (diabetic patients) and 2.5% in Group ND(non-diabetic patients). A statistically significant increase in difficult laryngoscopy was noted in patients in Group D. The incidence of the prayer sign was 31.25% in Group D and 13.75% in Group ND. A statistically significant increase in the incidence of the prayer sign was noted in patients in Group D . Four patients in Group D with the prayer sign had a difficult laryngoscopy. There was no significant association between difficult laryngoscopy and the prayer sign .

Hand abnormalities such as thickened tight waxy skin, and limitation of small joint mobility are common manifestations of diabetes. Although small joint mobility is usually limited to the hand, other joints might be involved. The term limited joint mobility (LJM) describes this phenomenon. It is seen more frequently in type I and type II diabetic patients than in the general population.
The prayer sign is a more simple bedside test for interphalangeal joint involvement. However, it can be detected in normal individuals.In the study, 13.75% of non-diabetic patients had the prayer sign

In the hands of diabetic patients, we have demonstrated a significant increase in LJM compared with non-diabetic patients as assessed by the prayer sign. The incidence of difficult laryngoscopy in long-term diabetic patients is high (27–31%). In our study it was 18.75%. The incidence of difficult laryngoscopy has been shown to be high in diabetic patients with LJM diagnosed using the palm print test. In this study, however, there was no relation between the prayer sign and difficult laryngoscopy.