Imaging diagnosis
Case 138
【Progress】She was given non-steroid anti-inflammatory drugs (NSAIDS) which induced relief of pain.
【Discussion】
Foot is largely categorized in three parts: forefoot, midfoot and hinder foot. There are the five major joints in foot; distal inter-pharanx joint; proximal interpharanx joint; metatarsal phalanx joint; Lisfranc joint complex: Chopart’s joint complex. Midfoot is the area which is encircled by Lisfranc joint and Chopart’s joint. Then, forefoot is the area anterior to Lisfranc joint while hider foot is the area posterior to Chopart’s joint (1).
Lisfranc joint complex consists of three articulations; tarsometatarsal (Lisfranc joint as narrow definition), intermetatarsal and intertarsal. Tarsometatarsal articulation (Lisfranc joint) is the joint between metatarsal bones [first, second, third, fourth, fifth] and tarsal bones [medial cuneiform bone, middle cuneiform bone, lateral cuneiform bone, cuboidal bone]. Meanwhile, Chopart’s joint is the line which connects taro-navicular joint and calcaneo-cuboidal joint (1).
There are interosseous ligaments among metatarsal bones from the second metatarsal to the fifth metatarsal, but there is no interosseous ligament between the first metatarsal bone and the second metatarsal bone. Instead, the connection called Lisfranc ligament exists between the medial cuneiform bone and the second metatarsal bone. Lisfranc ligament composed of the three parts: dorsal Lisfranc ligament, interosseous Lisfranc ligament and plantar Lisfranc ligament (1-4).
Lisfranc ligament is injured by direct force mechanism or indirect force mechanism. Direct force mechanism which rarely happens occurs by direct compression to the foot arch such as car accident, crush injury or fall from a height. Meanwhile, indirect force mechanism which usually happens occurs due to competitive sports such as acute abduction injury or acute forced plantar flexion (2-4)
Lisfranc ligament injury is categorized into three grades; Grade I, spray due to partial Lisfranc ligament injury without diastasis between the basal space of the first metatarsal and the second metatarsal; Grade II, rupture of Lisfranc ligament with diastasis of 1-5 mm between them; Grade III, rupture of Lisfranc ligament with diastasis of > 5mm (4).
CT is useful to detect a small bone fragment (avulsion) and minor lateral displacement of the second metatarsal (5). MRI with fat suppression T2WI is far useful in the evaluation to detect inflammatory edematous change of soft tissue of tendon and ligament (6-8). Further it helps to detect bone marrow edema, necrosis or microfracture. In our case, MRI with fat suppression showed local high signal intensity in the second metatarsal, indicating bone edema or necrosis.
【Summary】
We present an eighty two-year-old female suffering from pain of left foot joint with swelling and local heat. Left foot radiograph and MRI with fat suppression showed osteosclerosis of Lisfranc joint and bone edema or necrosis in the second metatarsal, respectively. It is borne in mind that midfoot is the area which is encircled by Lisfranc joint and Chopart’s joint. Lisfranc joint is the joint between metatarsal bones [first, second, third, fourth, fifth] and tarsal bones [medial cuneiform bone, middle cuneiform bone, lateral cuneiform bone, cuboidal bone]. Chopart’s joint is the line which connects taro-navicular joint and calcaneo-cuboidal joint. Lisfranc ligament injury is; Grade I, spray without diastasis between the basal space of the first metatarsal and the second metatarsal; Grade II, rupture of Lisfranc ligament with diastasis of 1-5 mm between them; Grade III, rupture of Lisfranc ligament with diastasis of > 5mm. MRI with fat suppression T2WI is useful in the evaluation to detect inflammatory edematous change of soft tissue of tendon and ligament.
【References】
1.De Palma L, et al. Anatomy of the Lisfranc joint complex. Foot Ankle Int 1997; 18:356-364.
2.Vuori JP, Aro HT. Lisfranc joint injuries: trauma mechanisms and associated injuries. J Trauma 1993; 35:40-45.
3.Solan MC, et al. Ligamentous restraints of the second tarsometatarsal joint: a biomechanical evaluation. Foot Ankle Int 2001; 22:637-641.
4.Nunley JA, et al. Classification, investigation, and management of midfoot sprains: Lisfranc injuries in the athlete. Am J Sports Med 2002; 30:871-878.
5.Lu J, et al. Radiographic and computed tomographic evaluation of Lisfranc dislocation: a cadaver study. Foot Ankle Int 1997; 18: 351-355.
6.Crim J. MR imaging evaluation of subtle Lisfranc injuries: the midfoot sprain. Magn Reson Imaging Clin N Am 2008; 16:19-27.
7.Preidler KW, et al. Conventional radiography, CT, and MR imaging in patients with hyperflexion injuries of the foot: diagnostic accuracy in the detection of bony and ligamentous changes. AJR Am J Roentgenol 1999; 173:1673-1677.
8.Castro M, et al. Lisfranc joint ligamentous complex: MRI with anatomic correlation in cadavers. AJR Am J Roentgenol 2010; 195:W447-455.
2019.2.20