Evaluation of various fibro-osseous tunnel pressures (carpal, cubital and tarsal) in normal human subjects.

Intra carpal, cubital and tarsal tunnel pressures were measured with open bore needle technique in 170 normal subjects. The pressure in carpal tunnel with wrist in neutral position was between 2.75 to 4.46 mm Hg which increased to 20-30 mm Hg. during flexion and extension of wrist. Pressures recorded in cubital tunnel were 2-5 mm Hg with full extended elbow and rose to 10-15 mm Hg and 20-28 mm Hg during 90 degrees flexion and full flexion of elbow respectively, pressures in tarsal tunnel were between 4-7 mm Hg in neutral position of ankle joint and with dorsi and plantar flexion of ankle it rose to 15-20 and 10-15 mm Hg respectively. There was no significant pressure difference between either sides and sexes; ages and proximally situated tunnel with distaly situated tunnel in same limb (Carpal tunnel Vs. Cubital tunnel). There was significant pressure difference between Carpal tunnel and Tarsal tunnel with wrist and ankle in their anatomical positions respectively.