Naoki Haraguchi

A New Interpretation of the Mechanism of Ankle Fracture

BACKGROUND Researchers have found it difficult to recreate a Lauge-Hansen supination-external rotation-type ankle fracture in experimental settings. We hypothesized that a pronation-external rotation mechanism could cause both distal, short oblique and high fibular fractures and that the fracture type would be affected by associated, laterally directed forces applied to the foot. Methlods: Twenty-three cadaver ankles were subjected to fracture loading that replicated the Lauge-Hansen pronation-external rotation mechanism with or without applying an external lateral force. In Phase I, an axial load was applied to fifteen specimens mounted on a materials testing machine. Each foot was rotated externally to failure. In Phase II, eight specimens were tested according to the Phase-I protocol, but external forces were applied laterally at the foot to increase the abduction moment at the ankle. Load and position versus time curves were recorded and were correlated with video image data to establish the sequence of failure of specific anatomic structures. RESULTS Eight specimens tested in Phase I sustained an oblique fracture of the distal end of the fibula with both medial and posterior injuries that occurred after the fibular fracture. Increasing the external lateral force and hence the abduction moment within the ankle (Phase II) resulted in three of eight specimens sustaining a high fibular fracture with a reversed fracture line (anterosuperior to posteroinferior) and/or a comminuted high fibular fracture. The distribution of traditional pronation-external rotation-type fractures differed significantly between Phase I and Phase II (p=0.032). CONCLUSIONS This study generated counterexamples to the Lauge-Hansen classification system by showing that a short oblique fracture of the distal end of the fibula can occur with the foot in the pronated position. Furthermore, a high fibular fracture was recreated by increasing the abduction moment at the ankle.

Avulsion Fracture of the Lateral Ankle Ligament Complex in Severe Inversion Injury Incidence and Clinical Outcome

Background Avulsion fracture of the lateral ankle ligaments is often undetected on early radiographs. The epidemiology and treatment of such avulsion fractures have received much less attention than the epidemiology and treatment of rupture of these ligaments. Hypothesis The clinical characteristics of avulsion fracture are different from those of ligament rupture. Unlike nonoperative treatment of lateral ligament rupture, nonoperative treatment of avulsion fracture does not yield satisfactory results. Study Design Cohort study; Level of evidence, 2. Methods A total of 169 consecutive patients with severe inversion injury were classified into a ligament rupture group or avulsion fracture group on the basis of physical examination findings and anterior talofibular ligament and calcaneofibular ligament radiographic views. Age, sex, activity level, and the mechanism of injury were analyzed. Patients in both groups were treated by casting. Follow-up examination of 152 patients included clinical assessment and functional evaluation based on the Karlsson system. Results Avulsion fracture was diagnosed in 44 (26%) of the 169 patients and was most common among children and patients over 40 years of age. Sedentary level activity and low-energy injury were more common in the avulsion fracture group than in the ligament rupture group (77% vs 37%, respectively, P = .001; 68% vs 43%, respectively, P = .004). Nonoperative treatment of avulsion fracture (mean Karlsson score, 89.1 points) yielded satisfactory results that were comparable with those of nonoperative treatment of ligament rupture (mean Karlsson score, 88.4 points) (P = .123). Osseous union was achieved in 65% of the patients with avulsion fracture. Conclusion Avulsion fracture of the lateral ankle ligaments in cases of severe inversion injury is more common than previously believed. Because of the high incidence and difficulty of detection in children, a high level of suspicion is necessary in order to obtain an accurate diagnosis of avulsion fracture in cases of severe inversion injury and to achieve adequate stability.

Prediction of Three-Dimensional Contact Stress and Ligament Tension in the Ankle During Stance Determined from Computational Modeling

Background: Our goal was to quantify and visualize the three-dimensional loading relationship between the ligaments and articular surfaces of the ankle to identify and determine the stabilizing roles of these anatomical structures during the stance phase of gait. Materials and Methods: We applied discrete element analysis to computationally model the three-dimensional contact characteristics and ligament loading of the ankle joint. Physiologic loads approximating those at five positions in the stance phase of a normal walk cycle were applied. We analyzed joint contact pressures and periankle ligament tension concurrently. Results: Most ankle joint loading during the stance phase occurred across the articular surfaces of the joint, and the amount of ligament tension was small. The tibiotalar articulation showed full congruency throughout most of the stance phase, with peak pressure developing anteriorly toward the toe-off frame. Of the periankle ligaments, the deep deltoid ligament transferred the most force during the stance phase (57.2%); the superficial deltoid ligament transferred the second-most force (26.1%). The anterior talofibular ligament transferred force between the talus and fibula continuously, whereas the calcaneofibular ligament did not carry force during gait. The distal tibiofibular ligaments and the interosseous membrane were loaded throughout the stance phase. Conclusion: Force transmission through the ankle joint during the stance phase is predominantly through the articular surfaces, and the periankle ligaments do not play a major stabilizing role in constraining ankle motion. The medial ligaments have a more important role than do the lateral ligaments in stabilizing the ankle joint. Clinical Relevance: In addition to ligament insufficiency, other factors, such as varus tilt of the tibial plafond, may be important in the development of recurrent instability. Continuous loading of syndesmosis ligaments provides a theoretical basis for evidence of syndesmosis screw breakage or loosening. The analysis method has potential applications for clarifying ankle joint function and providing a basis for comparison between normal and abnormal joint conditions.

Weight-Bearing-Line Analysis in Supramalleolar Osteotomy for Varus-Type Osteoarthritis of the Ankle

BACKGROUND We determined the preoperative and postoperative passing points of the mechanical axis of the lower limb at the level of the tibial plafond using a new method involving a full-length standing posteroanterior radiograph that includes the calcaneus (a hip-to-calcaneus radiograph) and correlated them to the clinical results after supramalleolar osteotomy for ankle osteoarthritis. METHODS We reviewed the hip-to-calcaneus radiographs of fifty lower limbs of forty-one patients treated for lower limb malalignment at our institution. The mechanical axis point of the ankle was the point at which the mechanical axis divides the coronal length of the plafond, expressed as a percentage. Four independent observers performed all measurements twice. Supramalleolar tibial osteotomy was performed in twenty-seven ankles (twenty-four patients) to treat moderate varus-type osteoarthritis of the ankle. The mean follow-up period was 2.8 years (range, two to 5.3 years). Clinical assessment was based on the American Orthopaedic Foot & Ankle Society (AOFAS) scale. RESULTS Interobserver and intraobserver reliability in identifying the mechanical ankle joint axis point were very high. The mean postoperative mechanical axis point was 50% (range, 13% to 70%) in ankles for which the preoperative point was ≤0%, whereas the mean postoperative point was 81% (range, 48% to 113%) in ankles for which the preoperative point was >0%. The mean change in AOFAS score was significantly less for patients with a preoperative point of ≤0% than for those with a preoperative point of >0% (p=0.004). Improvement was significantly greater in ankles with a postoperative mechanical ankle joint axis point of ≥80% than in ankles with a postoperative mechanical ankle joint axis point of <60% (p=0.030). CONCLUSIONS Traditional tibial correction resulted in great variation in the locations of the postoperative mechanical ankle joint axis point. In ankles with the preoperative point more medial than the tibial plafond, the point was insufficiently moved to the lateral side, and the clinical outcomes were less satisfactory.

Influence of activity level on the outcome of treatment of lateral ankle ligament rupture

BackgroundFew studies of treatment of lateral ankle ligament rupture have given careful consideration to the activity levels of patients. In the present study, we investigated whether a patient’s activity level influences the outcome of the treatment of lateral ankle ligament rupture and whether treatment should be determined according to activity level.MethodsA total of 115 consecutive patients with lateral ankle ligament rupture were treated with short-term cast immobilization followed by functional bracing. We divided preinjury activity levels and activity levels at follow-up into four classes according to the International Knee Documentation Committee standards. Follow-up examination 1 year after injury included clinical assessment (anterior drawer test, range of motion, maximum circumference of the calf, tenderness, swelling), reinjury assessment, and functional evaluation by means of the Karlsson scoring system.ResultsWe found significant differences in ankle stability and reinjuries between the four groups classified by their preinjury activity level. The number of patients with ankle instability and reinjury was significantly higher in the high-activity group than in the low-activity groups. We also found significant difference between groups classified by activity level at follow-up with regard to the Karlsson score.ConclusionsThe outcome of treatment of lateral ankle ligament rupture is significantly influenced by the patient activity level, and treatment may need to be determined according to this activity level.

Corrective osteotomy for malunited fracture of the glenoid cavity: a case report.

Fractures of the glenoid cavity that are substantially displaced are rare. A patient with shoulder pain and dysfunction caused by a severely malunited fracture of the glenoid cavity was treated successfully with corrective osteotomy and bone grafting. Functional results 2 years after surgery were satisfactory, and radiographs showed no evidence of degenerative change. Although appropriate initial management should prevent the development of symptomatic malunion, results of the current study suggest that later reconstruction of the glenoid cavity restores satisfactory function, even if so much time has elapsed that glenoid osteotomy must be done to achieve reduction.

Proposed novel unified nomenclature for range of joint motion: method for measuring and recording for the ankles, feet, and toes

The Ad Hoc Committee of Terminology of the Japanese Society for Surgery of the Foot (JSSF) proposes novel terminology for motion of the ankle, foot, and toe because there are some ambiguities in the current terminology. Articles were identified by searching the electronic databases of PubMed that compared definitions of American Orthopaedic Foot and Ankle Society (AOFAS), International Society of Biomechanics (ISB), and in the textbook of Kapandji as well as the American Academy of Orthopaedic Surgeons (AAOS). A total of 11 articles described the transverse (horizontal) plane motion in the hindfoot as external rotation/internal rotation and 10 as abduction/adduction. In all, 2 articles described the transverse (horizontal) plane motion in midfoot as external rotation/internal rotation and 10 as abduction/adduction. Another 4 articles described the transverse (horizontal) plane motion in the forefoot as external rotation/internal rotation and 8 as abduction/adduction. Altogether, 109 articles described the sagittal plane motion of the foot/ankle as dorsiflexion/plantarflexion and 20 as extension/flexion. In all, 99 articles described the frontal (coronal) plane motion of the foot/ankle as inversion/eversion and 4 as supination/pronation. Furthermore, 12 articles described the sagittal plane motion of toes as dorsiflexion/plantarflexion and 15 as extension/flexion. Another 16 articles described the frontal (coronal) plane motion of toes as supination/pronation and 1 as inversion/eversion. The transverse (horizontal) plane motion of the foot/ankle was defined as abduction/adduction in the hindfoot, midfoot, and forefoot; the sagittal plane motion of the foot/ankle was defined as dorsiflexion/plantarflexion; and the frontal (coronal) plane motion of the foot/ankle as inversion/eversion. The transverse (horizontal) plane motion of toes was defined as abduction/adduction; the sagittal plane motion of toes was defined as extension/flexion; and the frontal (coronal) plane motion of toes was defined as supination/pronation.

T1ρ mapping of articular cartilage grafts after autologous osteochondral transplantation for osteochondral lesions of the talus: A longitudinal evaluation: T1ρ Mapping of Articular Cartilage Graft

Clinical results of autologous osteochondral transplantation (AOT) for treatment of osteochondral lesions of the talus have been mixed. T1ρ imaging can be used to noninvasively detect early cartilage degeneration.