Operative versus conservative treatment of acute Achilles tendon ruptures: preliminary results of clinical outcome, kinematic MRI and contrast-enhanced ultrasound.

INTRODUCTION: There is no uniform consensus on the gold standard therapy for acute Achilles tendon rupture. The aim of this pilot study was to compare operative and conservative treatment regarding imaging findings and clinical outcome. MATERIALS AND METHODS: Surgically or conservatively treated patients with acute Achilles tendon rupture were retrospectively evaluated. Differences in tendon length and diameter with and without load were analysed using kinematic MRI, tendon perfusion, structural alterations, movement and scar tissue by means of grey-scale and contrast-enhanced ultrasound (CEUS). Intra- and interobserver agreement were recorded. RESULTS: No significant difference was detected regarding clinical outcome, B mode ultrasonography, contrast-enhanced sonography or MRI findings, although alterations in MRI-based measurements of tendon elasticity were found for both groups. Considerable elongation and thickening of the injured tendon were detected in both groups. CONCLUSION: Both, conservative and surgical treatment showed comparable outcomes in our preliminary results and may suggest non-inferiority of a conservative approach.

Simultaneous traumatic dislocation of the posterior tibial tendon and long peroneal tendon: a case report.

BACKGROUND: Viewing the existing literature, one can find several documents about dislocation of the peroneal tendons. Clinical findings, diagnostics, and therapy are well described. Instead, the list of documents describing dislocations of the posterior tibial tendon is short. We found no case in which a dislocation of both long peroneal tendon and posterior tibial tendon is described. CASE PRESENTATION: We present a case of a 29-year-old male patient who sustained an ankle injury after a fall at a boulder gym. He admitted himself with severe pain, tenderness, and swelling of his left ankle. Dislocation of the posterior tibial tendon and simultaneous dislocation of the long peroneal tendon was diagnosed using x-ray, computed tomography, and magnetic resonance imaging. Transosseous suture repair with periosteal augmentation of the flexor retinaculum was performed at the medial malleolus. At the lateral malleolus, transosseous suture was used to repair the superior retinaculum. The ankle was immobilized following surgery. The patient underwent physical therapy afterwards. The treatment resulted in good recovery, and the patient returned to the same level of performance at rock climbing. CONCLUSION: Our novel finding is that simultaneously sustained dislocations of the posterior tibial tendon and the long peroneal tendon may occur and can be successfully treated as if each injury is treated individually. Level of evidence Level V, case report.

Screw tip augmentation leads to improved primary stability in the minimally invasive treatment of displaced intra-articular fractures of the calcaneus: a biomechanical study.

PURPOSE: To investigate if the stability of minimally invasive screw osteosynthesis of displaced intra-articular calcaneal fractures (DIACF) can be effectively increased by an innovative approach to screw tip augmentation. METHODS: In eight-paired human cadaver hindfoot specimens, DIACF of Sanders type IIB were treated with either standard screw osteosynthesis or with bone cement augmentation of the screw tips in the main fragments. The instrumented specimens were subjected to a cyclic loading protocol (9000 cycles, with stepwise increasing loads, 100-1000 N). The interfragment motions were quantified as tuber fragment tilt (TFT) and posterior facet inclination angle (PFIA) using a 3-D motion analysis system. Böhler's angle (BA) was evaluated from X-rays. A load-to-failure test was performed after the cyclic loading protocol. RESULTS: All but one specimen of the augmented group withstood more cycles than the respective specimens of the non-augmented group. Mean cycles to failure for the failure criterion of 5° TFT were 7299 ± 1876 vs. 3864 ± 1810, corresponding to loads of 811 N ± 195 vs. 481 N ± 180, (P = 0.043). There were no significant differences observed in the PFIAs. The failure criterion of 5° BA was reached after a mean of 7929 cycles ± 2004 in the augmented group and 4129 cycles ± 2178 in the non-augmented group, corresponding to loads of 893 N ± 200 vs. 513 N ± 218, (P = 0,090). The mean load-to-failure of the four specimens in the augmented group that completed the cyclic loading was 1969 N over a 1742-2483 N range. CONCLUSION: Screw tip augmentation significantly improved the mechanical stability of the calcanei after osteosynthesis in terms of decreased tuber fragment tilts and less changes in Böhler's angle.

Subtalar arthrodesis stabilisation with screws in an angulated configuration is superior to the parallel disposition: a biomechanical study.

PURPOSE: The purpose of this study was to compare the stability of two established screw configurations (SC) for subtalar arthrodesis using a cyclic loading model. METHODS: Eight paired human cadaver hindfoot specimens underwent subtalar arthrodesis with either parallel or angulated SC. The instrumented specimens were subjected to a cyclic loading protocol (1000 cycles: ±5 Nm rotation moment, 50 N axial force). The joint range of motion (ROM) was quantified before and after cyclic loading, in the three principal motion planes of the subtalar joint using pure bending moments of ±3 Nm. RESULTS: After instrumentation, the angulated SC showed significantly less mean ROM compared to the parallel SC in internal/external rotation (1.4° ± 2.2° vs. 3.3° ± 2.8°, P = 0.006) and in inversion/eversion (0.9° ± 1.4° vs. 1.5° ± 1.1°, P = 0.049). After cyclic loading, the angulated SC resulted in significantly less mean ROM compared to the parallel SC in internal/external rotation (3.3° ± 4.6° vs. 8.8° ± 8.0°, P = 0.006) and in inversion/eversion (1.9° ± 2.3° vs. 3.9° ± 3.9°, P = 0.017). No significant differences in the mean ROM were found between the angulated and parallel SC in dorsal extension/plantar flexion. CONCLUSION: The angulated SC resulted in decreased ROM in the subtalar arthrodesis construct after instrumentation and after cyclic loading compared to the parallel SC. The data from our study suggest that the clinical use of the angulated SC for subtalar arthrodesis might be superior to the parallel SC.

Motion of the fibula relative to the tibia and its alterations with syndesmosis screws: A cadaver study.

BACKGROUND: The motion of the fibula in relation to the tibia is coupled on the motion of the talus in the ankle joint. Several authors investigated this motion with different methods. An injury of the elastic fixation of the fibula to the tibia and its treatment with the syndesmotic set screw has an impact on this motion. METHODS: The motion of the fibula relative to the tibia was measured in eight embalmed human above the knee amputated cadaver specimens using a 3D-motion analysis system. The relative motion was measured from 50° of plantar flexion to 30° of dorsiflexion. Experiments were performed in the following conditions: without fixation and intact ligaments, after sectioning of the four syndesmotic ligaments and the interosseous membrane, and application of either a tricortical screw, or a quadricortical screw or two quadricortical screws. RESULTS: Concordant movements of the lateral malleolus were a medial translation during plantar flexion, external rotation around the sagittal axis during plantar and dorsiflexion. The motion of the proximal fibula was smaller and more variable than in the distal part. After sectioning of the syndesmosis the range of motion, compared to the intact state increased, particularly in translation along the transversal (118%), sagittal (160%) and the longitudinal (136%) axis and in axial rotation (145%). Syndesmotic screws reduced the range of motion in transversal (p<0.006) and sagittal translation (p<0.011) and axial rotation. CONCLUSION: The small relative motion of the tibia and fibula is increased by syndesmotic injuries. Syndesmosis screws significantly limit this increased relative motion below physiologic values, which makes it necessary to remove the screws before flexion in the ankle joint is performed.