<Tr> <Td> fingers </Td> <Td> the flexor digitorum profundus acting on the proximal and distal joints, and the flexor digitorum superficialis acting on the proximal joints </Td> <Td> mainly by the lumbricals and interossei, the long extensors having little or no action upon these joints </Td> </Tr> <Tr> <Td> thumb </Td> <Td> the flexor pollicis longus </Td> <Td> the extensor pollicis longus </Td> </Tr> <P> The relative length of the digit varies during motion of the IP joints . The length of the palmar aspect decreases during flexion while the dorsal aspect increases by about 24 mm . The useful range of motion of the PIP joint is 30--70 °, increasing from the index finger to the little finger . During maximum flexion the base of the middle phalanx is firmly pressed into the retrocondylar recess of the proximal phalanx, which provides maximum stability to the joint . The stability of the PIP joint is dependent of the tendons passing around it . </P> <P> Rheumatoid arthritis generally spares the distal interphalangeal joints . Therefore, arthritis of the distal interphalangeal joints strongly suggests the presence of osteoarthritis or psoriatic arthritis . </P>

Where would the interphalangeal joint be found in the foot