Table 2.

Predicted difficulty of spinal anaesthesia.

Anaesthetists subjective prediction of Difficulty	Easy	64
	Difficult	36
Palpability of bony landmarks	Easily palpable	53
	Poorly palpable	35
	Impalpable	12
Predicted spinal anaesthesia difficulty scoring (after Atallah)	Easy (grade 0–3)	63
	Easy (grade ≥4)	37

Data are presented as n (= %). Atallah's spinal anaesthesia difficulty score comprises nine difficulty grades. Grade 4 is the difficulty grade at or above which difficulty is expected. Grades are calculated based on the sum of specific scores assigned for BMI, age, bony landmark palpability, radiological characteristics, and spinal deformity [13].