Correlation of weightbearing radiographs and stability of stress positive ankle fractures.

BACKGROUND: A positive external rotation stress test has been used as an indication for operative treatment of fractures of the lateral malleolus. The objective of the current study was to ascertain the results of a protocol initially treating stress positive ankle fractures nonoperatively and utilizing weightbearing radiographs in surgical decision making. METHODS: We performed a prospective study of lateral malleolar fractures with an associated medial ligamentous injury. All patients with fractures of the lateral malleolus with medial sided symptoms and/or signs, and an intact ankle mortise underwent an external rotation stress test to confirm injury to the deltoid ligament (stress positive). Patients with a positive stress test were placed in a short-leg walking cast and seen in 7 days where weightbearing radiographs of the ankle were obtained. If the radiographs demonstrated an intact mortise, then nonoperative treatment was continued. If the weightbearing radiographs demonstrated medial clear space widening, then the patient was offered operative treatment to restore the congruency of the ankle mortise. Patients were assessed for conversion to operative treatment, complications, and functional outcome. Thirty-eight patients were enrolled in the study. Using Lauge-Hansen classification 36 (95%) were stress positive supination-external rotation fractures and 2 (5%) were stress positive pronation-external rotation fractures. Followup assessment was performed at a minimum of 6 months and averaged 12 months. RESULTS: Weightbearing radiographs at the first post-injury clinic visit had an average medial clear space of 2.9 ±0.9 mm. Three (8%) patients met our criteria for medial clear space widening and underwent operative treatment. Of these three patients, two were pronation-external rotation fracture patterns. Therefore, 3% of the supination-external rotation IV fractures, and all of the pronation-external III/IV rotation fractures ultimately required operative treatment. At final followup, the average AOFAS hindfoot score was 92 ±8.1. CONCLUSION: Ligamentous supination-external rotation Stage IV fractures with an intact mortise on static radiographs can be initially treated nonoperatively. Weightbearing radiographs should be utilized to assess congruency of the ankle mortise during an early post-injury visit. Utilizing this approach, a significant number of surgeries were avoided, and good to excellent results were obtained. From our early experience, nonoperative treatment of pronation-external rotation III/IV injuries using this protocol is not recommended.

Increased plantar foot pressure in persons affected by leprosy.

Although foot pressure has been reported to be increased in people affected by leprosy, studies on foot pressure and its determinants are limited. Therefore, the aim was to assess barefoot plantar foot pressure and to identify clinical determinants of increased plantar foot pressure in leprosy affected persons. Plantar pressure in both feet was assessed using the Novel EMED-X platform in 39 persons affected by leprosy. Peak pressure was determined for the total foot and four regions: hallux, metatarsal heads, midfoot and heel. Potential determinants were: age, weight, nerve function (Neuropathy Disability Score, Pressure Perception Threshold and Vibration Perception Threshold), toe and foot deformities, joint mobility, ankle muscle strength and callus. Increased peak pressure (>600kPa) was observed in 46% of the participants. The highest peak pressure (mean) was found in the metatarsal heads region (right 549 (SD 321)kPa; left 530 (SD 298)kPa). Multilevel regression analysis showed that Neuropathy Disability Score, amputation/absorption of toes and hallux valgus independently contributed to metatarsal heads peak pressure in persons affected with leprosy. To conclude, peak pressure is increased in people affected by leprosy. The highest peak pressure is found in the forefoot region and is significantly associated to Neuropathy Disability Score, toe amputation/absorption and hallux valgus. Screening for clinical characteristics can be used to identify individual persons affected by leprosy at risk of excessive pressure.

[The role of the tibiofibular syndesmotic and the deltoid ligaments in stabilizing Weber B type ankle joint fractures--an experimental investigation]. / Beitrag der Syndesmosen und des Deltabandes zur Stabilität der Aussenknöchelfraktur Typ Weber B. Eine experimentelle Untersuchung.

The purpose of the present biomechanical investigation was to check the functional importance of the syndesmosis ligaments and of the deltoid ligament for ankle fracture type B according to the AO-Weber classification. We constructed a special fixation clamp, with 12 fresh and unembalmed lower legs being tested for lateral shift (mm) and ten for tibiotalar rotation. All specimens were exposed in the same neutral position. Transverse loads (F(y)) varied between 0 and 150 N, axial loads (F(z)) between 0, 300, 600 and 1,000 N and rotational loads (F(r)) between 2.4 and 4.9 Nm. All series were repeated according to supination-eversion (SE) injury patterns of the Lauge-Hansen classification. Syndesmotic ligaments and the fibula were incrementally sectioned from anterior to posterior. Type SE I consisted of an isolated incision of the anterior syndesmosis ligament. Type SE II had an additional oblique fracture of the fibula at the height of the tibiofibular syndesmosis. In type SE III injuries, in addition to the fibular fracture, a complete rupture of the syndesmosis ligaments was present, and for type SE IV lesions the deltoid ligaments were incised. The transverse load-displacement curve was s-shaped in all uninjured joints,with the highest gradient between 10 and 20 N with no axial compression. Without axial compression in cases of F(y)=25 N transverse loads, the mean talus translation was 0.51 mm. Following type II injuries, the average talus translation was 0.68 mm (not significant) and rose to an average of 0.95 mm ( P <0.01) in type III injuries. After additional incision of the deltoid ligaments, the ankle joint subluxed permanently when more than 5-10 N transverse loads were applied. Axial loads of 300 N or more resulted in a considerable reduction in talus translations, indicating increased stability and congruency within the joint complex. In this way, the vertical loading of the ankle joints always contributed to joint stability. The average internal tibiotalar rotation reached with a torque of 2.4 Nm was 3.52 degrees and with 4.9 Nm 5.15 degrees when no axial compression was applied. External rotation measured -6.36 degrees and -8.62 degrees, respectively. Following the experimental protocol, significant increases were noted for external rotation at SE II degrees injuries ( P =0.003) and for internal rotation at SE III degrees ( P =0.03) injuries. Our data support the proposition that the deltoid ligaments and the posterior syndesmosis play a key role in the stability of ankle fractures for supination-eversion injuries. If these structures remain intact, conservative and early functional treatment are recommended in patients with minimal (<2 mm) or no fracture displacement. This concept is confirmed by the literature dealing with clinical mid- and long-term follow-up studies.