Answer for BIR CoW 30 Jan 2022
Painful os peroneus syndrome ( POPS)
Findings
Fragment of bone seen along the peroneus longus tendon on sonography which is close to the calcaneocuboid junction . Sonography shows a calcified area seen along the course of peroneus longus tendon with mild edema. Two fragment are noted close to each other (separation of less than 2 mm ) on CT with smooth cortex - bipartite os peroneus .(Unlike nondisplaced os peroneum fracture, where margins are irregular ) and surrounding edema.
Discussion
The os peroneum is a small ossicle located within the substance of the peroneus longus tendon at the inferolateral aspect of the base of the cuboid. The os Peroneum is present in the substance of the The peroneus longus tendon proximal to cuboid tuberosity/tunnel. Normal os peroneum location ranges between 7 mm proximal and 8 mm distal to the calcaneocuboid joint. Normally seen in up to 30% of people, the os peroneum is bipartite in 30% . Painful os peroneus syndrome ( POPS): Includes- fracture of the ossicle,partial or complete rupture of the peroneus longus tendon and diastasis of the bipartite ossicle. POPS should be considered in patients with pain in the lateral midfoot. Sonopalpation over the ossicle will often elicit pain, POPS may be secondary to trauma but the initial injury is often missed and the patient can present with chronic pain. Plain radiographs, MRI, and ultrasound are useful in the diagnosis of POPS. Os peroneum fragment separation of ≥6mm, or proximal displacement of the proximal fragment by ≥10mm from the calcaneocuboid joint on lateral radiograph has 100% concordance with full thickness peroneus longus tendon tear. Fragment separation of 2 mm or less, or proximal displacement of 8 mm or less is associated with normal tendons, partial thickness tear, or only tendinosis . The peroneus longus is a powerful evertor of the foot so surgical intervention is necessary to repair a fully torn tendon. Since POPS may arise from a wide spectrum of conditions, Radiologists play an essential role in the diagnosis of POPS.
Findings
Fragment of bone seen along the peroneus longus tendon on sonography which is close to the calcaneocuboid junction . Sonography shows a calcified area seen along the course of peroneus longus tendon with mild edema. Two fragment are noted close to each other (separation of less than 2 mm ) on CT with smooth cortex - bipartite os peroneus .(Unlike nondisplaced os peroneum fracture, where margins are irregular ) and surrounding edema.
Discussion
The os peroneum is a small ossicle located within the substance of the peroneus longus tendon at the inferolateral aspect of the base of the cuboid. The os Peroneum is present in the substance of the The peroneus longus tendon proximal to cuboid tuberosity/tunnel. Normal os peroneum location ranges between 7 mm proximal and 8 mm distal to the calcaneocuboid joint. Normally seen in up to 30% of people, the os peroneum is bipartite in 30% . Painful os peroneus syndrome ( POPS): Includes- fracture of the ossicle,partial or complete rupture of the peroneus longus tendon and diastasis of the bipartite ossicle. POPS should be considered in patients with pain in the lateral midfoot. Sonopalpation over the ossicle will often elicit pain, POPS may be secondary to trauma but the initial injury is often missed and the patient can present with chronic pain. Plain radiographs, MRI, and ultrasound are useful in the diagnosis of POPS. Os peroneum fragment separation of ≥6mm, or proximal displacement of the proximal fragment by ≥10mm from the calcaneocuboid joint on lateral radiograph has 100% concordance with full thickness peroneus longus tendon tear. Fragment separation of 2 mm or less, or proximal displacement of 8 mm or less is associated with normal tendons, partial thickness tear, or only tendinosis . The peroneus longus is a powerful evertor of the foot so surgical intervention is necessary to repair a fully torn tendon. Since POPS may arise from a wide spectrum of conditions, Radiologists play an essential role in the diagnosis of POPS.
Note:
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!