The Radiological Measurement,Biomechanical And Clinical Study Of The Tarsometatarsal Joint

The Lisfranc joint is an extraordinarily complex structure. The Lisfranc joint absorbs high concentrations of force, especially during propulsive activities. Therefore, its function depends on the structural integrity of a vast network of ligaments connecting multiple small bones with numerous articulations.The Lisfranc joint, or tarsometatarsal articulation of the foot, is named for Jacques Lisfranc, a field surgeon in Napoleon's army. Lisfranc described an amputation performed through this joint because of gangrene that developed after an injury incurred when a soldier fell off a horse with his foot caught in the stirrup. The boundaries of the midfoot are delineated by Lisfranc joint complexes. Its integral components frequently function as a single entity.This durable osseoligamentous structure absorbs and transmits high levels of force from the adjacent hind- and forefoot. Stability of the tarsometatarsal joint results from its unique osseus, ligamentous, and tendinous architecture.The anatomic complexity at the Lisfranc joint complex leads to multiple injury patterns. The longitudinal and transverse arches are integral to the Lisfranc joint 's structural design. A Roman style arch—the foot's transverse arch—is created by the alignment of the three cuneiforms and cuboid, The second metatarsal base securely locks into this three-dimensional dovetail, providing primary rigid stability at the mid- and forefoot junction. A vast network of dense plantar ligaments, inter-osseous ligaments, capsular structures, and fascia directly support the bony morphology of the arches. Additional dynamic support is provided by the plantar fascia , plantar fascia ,anterior tibialis, posterior tibialis, and peroneus longus muscles and their named tendons.In the current, The study of Lisfranc joint ,which is an extraordinarily complex structure, is still poorly understood. The incidence of Lisfranc joint fracturedislocations is one case per 55,000 persons each year. These injuries account for fewer than 1 percent of all fractures.23 As many as 20 percent of Lisfranc joint injuries are missed on initial anteroposterior and oblique radiographs. The treatment of Lisfranc joint complex fracture-dislocations remains controversial. No consensus exists regarding the most effective treatment for Lisfranc joint injury. Controversies exist as to the best method of treatment for these injuries including open or closed reduction, use of screws or Kirshner wires, the timing of treatment and duration of immobilisation.Some investigators' believe that nonoperative management of fractures and fracturedislocations is ineffective, because the reduction and alignment that occur with casting are lost when soft tissue swelling decreases.Some treatment often lead to long term pain and disability. Early diagnosis and prompt accurate reduction and stabilisation will minimise long-term disability. However, in general, a consensus exists that precise anatomical reduction and stabilization should be achieved as soon as is possible.Lisfranc joint injuries are difficult to assess; therefore, a high index of clinical suspicion is necessary to fully evaluate the extent of injury. Appropriate static and dynamic tests are invaluable in this regard. Restoration of bony alignment, ligamentous integrity, and joint congruity are critical aspects of successful treatment. Unfortunately, appropriate treatment of traumatic midfoot injuries rarely results in excellent results. Advances in the evaluation and treatment of Lisfranc joint injuries continue to evolve.We performed a retrospective study of all patients with different group,had done the radiological measurement of the tarsometatarsal joints to find the anatomy of tarsometatarsal joints stability. An investigation of the in-vitro biomechanical testing of individual TMT joints demonstrating an apparent pressure-regulating mechanism of the Lisfranc complex with varying load and position. To study the contact mechanics and pressure distribution in the tarsometatarsal joints in normal adult cadaveric feet in order to develop a foundation : the one and second tarsometatarsal joints provides critical biomechanical propert during propulsive activities. We had studied the fresh-frozen cadaveric foot specimens and made the model of Lisfranc ligament injuried , which arised from the lateral surface of the medial cuneiform and inserts medially on the base of the second metatarsal,to find how the Lisfranc ligament provides stability between the medial cuneiform and the second metatarsal and develop a foundation for more effective treatment of the Lisfranc ligament.。We had a retrospective study reviewed 74 patients who underwent plaster fixation , Kirschner wire fixation ,AO screw fixation to find more effective treatment of the tarsometatarsal joints dislocation. The experiment was divided into four parts.Part 1 The radiological measurement of the tarsometatarsal jointsObjective: The anatomy of the mortise of the Lisfranc joint between the medial and lateral cuneiforms was studied.Methods: In 34 consecutive people and patients with Lisfranc injuries we measured using standard anteroposterior (AP) and 45 deg oblique radiographs with the 500mA Siemens DR. Radiographs were taken with the 90cm, a modified beam directed at a 28-32 deg cephalad angle was used to maximize visualization of the TMT joint. We measured the medial depth of the mortise (A), the length of the second metatarsal (B) the lateral depth (C) and the distance between the one and second metatarsal(D). All the radiographs were taken at a standardised distance of 90cm with the 500mA Siemens DR. MRI was used to confirm the diagnosis. We calculated the mean depth of the variables of the lever arm as follows: A/B, C/B.Results: There was significantly difference of gender, the measurements of the medial mean depth of the mortise 9.5 mm, females 10.4 mm , males 8.5 mm; the lateral mean depth of the mortise 5.3 mm, females 6.0 mm , males 4.5mm. There was significantly difference of classification for the measurements, the medial mean depth of the mortise : the fracture-dislocation 9.4 mm , only ligamentous lesion 8.3 mm; the lateral mean depth of the mortise : the fracture-dislocation 5.3 mm , only ligamentous lesion 3.9 mm. There was no significantly difference of the mean distance between the one and second metatarsal four groups 1.58mm,1.49mm,1.47mm,1.48mm.Conclusions:①The base of the second metatarsal is recessed proximally in relation to the other tarsometatarsal joints and is well connected through ligaments to all cuneiforms. This joint is critical to the integrity of tarsometatarsal joint complex. The lateral depth of the mortise is very important.②There was statistically significant relationship to gender and classification for each of the measurements of the tarsometatarsal joint. The females had a higher risk of injury to the Lisfranc joint complex than males; the fracture-dislocation had a higher risk of injury to the Lisfranc joint complex than only ligamentous lesion.③Standard radiography remains a primary diagnostic modality in acute foot and ankle trauma. Multidetector CT with high-quality multiplanar reconstruction (MPR) is recommended as a complementary examination in high-energy injury in patients with multiple trauma or in patients in whom radiographic images are equivocal. This may reveal Lisfranc fracture-dislocations, show the extent of the fracture-dislocation, and reveal occult fractures in other parts of the foot and ankle.Part 2 The contact mechanics and pressure distribution in the tarsometatarsal jointsObjective: To study the contact mechanics and pressure distribution in the tarsometatarsal joints in normal adult cadaveric feet in order to develop a foundation for more effective treatment. Methods: Eight fresh-frozen cadaveric foot specimens were studied. Six specimens were from men and two were from women.There was no evidence of previous trauma or arthrosisin any of the specimens. The specimens were transected approximately 20 cm proximal to the ankle, All soft tissue was removed from the proximal parts of the tibia and fibula of the eight specimens, but the interosseous membrane was left intact. The dissected proximal aspects of the tibia and fibula were then potted in the jig potting while the foot was maintained in a neutral stance position. The specimens were placed in specially designed testing devices attached to The CSS-44020 machine of vitodynamics. A transverse incision was made in the dorsum of the midfoot over the tarsometatarsal joint spaces. The dorsal tendons and supporting dorsal ligaments were transected. The articulating surfaces of the tarsometatarsal joints were exposed by making five incisions into the tarsometatarsal joint spaces.The fixtures had a universal joint to align the specimens for testing along the direction of the ligament fibers, which was then locked. During the testing procedure, the specimens were kept moist with saline solution.Intra-articular pressures and contact areas of the tarsometatarsal joints were quantified with single-use pressure-sensitive film (Fuji C. Itoh). The pressure-sensitive film was cut to shape with use of five custom steel-rule dies. These dies accurately and reproducibly cut the film into shapes approximating the contours of the five distal articulating surfaces of the tarsometatarsal joints. These pieces of film were sealed with clear packaging tape, thus preventing the intrusion of artifact-causing moisture. The pressure-sensitive film were inserted through the dorsal incisions into their respective tarsometatarsal joint spaces. The foot-specimen positioning jig was designed to reproducibly hold the specimen to The CSS-44020 machine of vitodynamics, and was mounted on the loading platform of the test apparatus. ankle were performed in neutral position ,plantar flexion 30°, plantar flexion 60°with external fixation when the foot with neutral inversion and eversion. For each position,the specimen was applied 10N/s load , was held at the maximum pressure 600N for five seconds, and then was released.Results: During ankle joint in neutral position increasing plantar flexion under the 600-N axial load, the contact pressure within each of the tarsometatarsal joints ranged only from 0.693 to 0.834Mpa, has no significant differences (P>0.05);Significant changes were associated with in tarsometatarsal joint contact areas and forces. When ankle joint in the 0°of plantar flexion, the first tarsometatarsal joints contact areas were 146.3±13.6mm2 and forces were 112.6±11.3N ;the second tarsometatarsal joints contact areas were 190.1±24.7 mm2 and forces were 150.5±15.9N ;the third tarsometatarsal joints contact areas were 171.2±23.6 mm2 and forces were 136.6±13.2N ; the fourth tarsometatarsal joints contact areas were 91.6±8.6 mm2 and forces were 63.2±6.1N ;the fifth tarsometatarsal joints contact areas were 62.5±5.8 mm2 and forces were 51.3±5.3 N. When ankle joint in the 30°of plantar flexion, the first tarsometatarsal joints contact areas were 190.4±20.3 mm2 and forces were 150.2±14.7N ;the second tarsometatarsal joints contact areas were 198.7±18.6 mm2 and forces were 164.3±15.4N ;the third tarsometatarsal joints contact areas were 165.8±15.3 mm2 and forces were 140.5±13.7N ; the fourth tarsometatarsal joints contact areas were 66.5±6.1 mm2 and forces were 48.1±5.2N ;the fifth tarsometatarsal joints contact areas were 31.3±3.6 mm2and forces were 24.3±2.3 N. When ankle joint in the 60°of plantar flexion, the first tarsometatarsal joints contact areas were 229.3±23.2 mm2 and forces were 186.7±17.9N ;the second tarsometatarsal joints contact areas were 200.2±21.4 mm2 and forces were 169.9±17.1N ;the third tarsometatarsal joints contact areas were 149.4±13.6 mm2 and forces were 124.3±12.3N ; the fourth tarsometatarsal joints contact areas were 45.3±4.7 mm2 and forces were 36.3±3.8N ; the fifth tarsometatarsal joints contact areas were 20.4±2.9 mm2and forces were 15.1±2.1N. During ankle joint increasing plantar flexion, the first tarsometatarsal joints contact areas and forces tend to increase, has no significant differences (P<0.01); the second tarsometatarsal joints contact areas and forces have no significant differences (P<0.05); the third/fourth/ fifth tarsometatarsal joints contact areas and forces tend to decrease, has significant differences (P<0.01).Conclusions:The biomechanical studies contact pressures and force of TMT function with pressure-sensitive film under the 600-N axial load. When ankle joint in neutral position, the first/sceond tarsometatarsal joints transfer high loads, were major part of TMT bearing weight. During ankle joint increasing plantar flexion, the fourth/fifth tarsometatarsal joints contact forces tend to decrease, and the first tarsometatarsal joints contact forces tend to increase, the medial two columns were major part of TMT bearing weight. Despite varying foot positions under the same axial load, contact pressures were regulated by varying the joint surface area. Part 3 The mechanical behavior of the Lisfranc ligaments in the forfootObjective: To define mechanical properties of the Lisfranc ligament stabilizing the medial tarsometatarsal joints in the forfoot under normal conditions.Methods: Six fresh-frozen cadaveric foot specimens were studied. Four specimens were from men and two were from women.There was no evidence of previous trauma or arthrosisin any of the specimens. The dissected proximal aspects of the tibia and fibula were then potted in the custom jig while the foot was maintained in a neutral stance position.Mechanical testing was performed with the CSS-44020 vitodynamics machine of vitodynamics. The specimens were attached to the vitodynamics machine and the ankle joint was held in 30 degrees of plantarf lexion with external fixation when the foot with neutral inversion and eversion. During the testing procedure, the specimens were kept moist with saline solution. The articulating surfaces of the tarsometatarsal joints were exposed by making five incisions into the tarsometatarsal joint spaces, dorsal ligament,Lisfranc ligament and plantar ligaments were next sharply sectioned, then loaded. The feet were preloaded with 10N, ten load cycles were applied at arate of 10N/s to a maximum load of 100N, the load was maintained for five seconds and then was released.The displacements of the first and second metatarsal heads were measured using linear variable differential transducers, which was set in the dorsal aspect of the the first and second metatarsal base.Results: There were differences for displacement of four groups. In group with initial specimens, the displacement was 0.00058±0.00013mm/N; In group specimens with sectioned dorsal ligaments, the displacement was 0.00072±0.00015mm/N; In group specimens with sectioned dorsal ligaments and Lisfranc ligament, the displacement was 0.00216±0.00053mm/N; In group specimens with sectioned all ligaments, the displacement was 0.00214±0.00062mm/N. Between specimens within pairs within either group, the displacement of initial specimens (0.00058±0.00013mm/N) and specimens with sectioned dorsal ligaments (0.00072±0.00015mm/N) were significantly different than that of the specimens with sectioned dorsal ligaments and Lisfranc ligament (0.00216±0.00053mm/N) and specimens with sectioned all ligaments (0.00214±0.00062mm/N). There was no significant difference in the displacement between initial specimens (0.00058±0.00013mm/N) and specimens with sectioned dorsal ligaments (0.00072±0.00015mm/N); There was no significant difference in the displacement between specimens with sectioned dorsal ligaments and Lisfranc ligament (0.00216±0.00053mm/N) and specimens with sectioned all ligaments (0.00214±0.00062mm/N).Conclusions:Injuries with isolated rupture of the dorsal ligament may not be as destabilizing as injuries with ruptured Lisfranc ligament or plantar ligaments and, that the former may be managed nonoperatively; The Lisfranc ligament arised from the lateral surface of the medial cuneiform and inserts medially on the base of the second metatarsal, the Lisfranc ligament provides critical stability between the medial cuneiform and the second metatarsal.With the load adding, displacement be enlarged. Maybe when ankle joint was to incur enormous load, the transverse arch of foot become low,plantar ligaments provide more strongly stability between the medial cuneiform and the second metatarsal。Part 4 Treatmen t of injury of tarso-metatarsal jointObjective: To evaluate the treatment methods and clinical effectiveness of dislocation and fracture-dislocation of tarsometatarsal joint.Methods: We performed a retrospective study of eighty-five patients with Lisfranc injury in a seven-year period. Among seventy-four patients, twenty-four treated with plaster fixation ,twenty-two treated with Kirschner wire fixation, twenty-eight treated with screw fixation. Twenty-one injuries were purely ligamentous, and fifty-three were combined ligamentous and osseous. Patient outcome was assessed with use of the American Orthopaedic Foot and Ankle Society (AOFAS) midfoot score. Evaluate the clinical results after treatment with the different groups.Results: Seventy-four patients were followed for an average of eighteen months.Patient outcome was assessed with use of the American Orthopedic Foot and Ankle Society midfoot score.Among the patients: excellent with twenty-three patients,good with the twenty-four patients, fair with the seventeen patients, good with the ten patients, the good and excellent rate of results is 63.5%. Evaluate the clinical results after treatment with the different groups: the good and excellent rate of purely ligamentous injury group is 38.1%, the good and excellent rate of combined ligamentous and osseous injury group is 73.6%, there were significant differences between the two groups(P<0.005); the good and excellent rate of plaster fixation is 33.3%, the good and excellent rate of Kirschner wire fixation is 63.6%, the good and excellent rate of screw fixation is 89.3%.there were significant differences between the three groups(P<0.005).Conclusions:Anatomical reduction and screw fixation of a Lisfranc injury leads to the best long-term outcomes ,but purely ligamentous injuries have a poor outcome despite such surgical management. The most notable limitations following treatment included mild pain, use of orthotics, and restricted recreational activities.