[Supramalleolar osteotomy in asymmetric ankle osteoarthritis : Short-term clinical and radiographic results]. / Supramalleolare Osteotomie bei asymmetrischer Arthrose des oberen Sprunggelenks : Kurzfristige klinische und radiologische Ergebnisse.

BACKGROUND: The main indication for the supramalleolar osteotomy is asymmetric ankle osteoarthritis with concomitant supramalleolar valgus or varus deformity. The aim of this prospective study was to analyze short-term clinical and radiographic outcomes in patients with asymmetric ankle osteoarthritis. METHODS: A total of 16 patients with asymmetric ankle osteoarthritis and concomitant supramalleolar deformity - 7 patients with valgus deformity, 9 patients with varus deformity - were treated. Intraoperative and postoperative complications were recorded and analyzed. The clinical and radiographic outcomes were assessed after a mean follow-up of 3.6 ± 1.1 years. RESULTS: In 10 of 16 patients, removal of hardware was performed. The AOFAS hindfoot score increased significantly after surgery. All categories of the SF-36 score showed significant improvement. The average range of motion also increased significantly. Radiographic assessment showed neutral hindfoot alignment at the latest follow-up. The postoperative clinical outcomes were comparable in both patient groups. The time until complete osseous union was significantly longer in patients with opening wedge osteotomy. CONCLUSION: This prospective study demonstrated encouraging short-term results in patients with asymmetric ankle osteoarthritis who underwent supramalleolar osteotomy. In progressive ankle osteoarthritis, joint-nonpreserving treatment options including total ankle replacement or ankle arthrodesis should be discussed.

Joint instability leads to long-term alterations to knee synovium and osteoarthritis in a rabbit model.

OBJECTIVES: Joint instability is believed to promote early osteoarthritic changes in the knee. Inflammatory reactions are associated with cartilage degradation in osteoarthritis (OA) but their possible synergistic or additive effects remain largely unexplored. The goal of the present study was to investigate the in vivo effects of Botulinum Toxin A (BTX-A) induced joint instability on intraarticular alterations in an otherwise intact rabbit knee joint model. METHODS: Ten 1-year-old female New Zealand White rabbits (average 5.7 kg, range 4.8-6.6 kg) were randomly assigned to receive three monthly unilateral intramuscular injections of BTX-A (experimental group), or no treatment (control group). After 90 days, all knees were analyzed for specific mRNA levels using RT-qPCR. The synovium and cartilage tissue was assessed for histological alterations using the OARSI scoring system. RESULTS: Cartilage and synovial histology showed significant higher OARSI scores in the BTX-A group animals compared to the untreated controls and contralateral limbs. There were no differences between the untreated control and the contralateral experimental limbs. Gene expression showed significant elevations for collagen I, collagen III, nitric oxide, TGF-ß, IL-1 and IL-6 compared to the healthy controls. CONCLUSION: BTX-A induced joint instability in a muscle weakness model uniquely leads to alterations in gene expression and histological changes in the synovial membranes and cartilage in otherwise intact knee joints. These results lead to the conclusion that joint instability may promote an inflammatory intraarticular milieu, thereby contributing to the development of OA.

Total ankle replacement in patients with von Willebrand disease: mid-term results of 18 procedures.

von Willebrand disease (VWD) is a recognized cause of secondary ankle osteoarthritis (OA). Few studies have examined orthopaedic complications and outcomes in VWD patients treated for end-stage ankle OA with total ankle replacement (TAR). To determine the clinical presentation, intraoperative and postoperative complications and evaluate the mid-term outcome in VWD patients treated with TAR. Eighteen patients with VWD with mean age 47.3 years (range = 34.0-68.7) were treated for end-stage ankle OA with TAR. The mean duration of follow-up was 7.5 years (range = 2.9-13.2). Intraoperative and perioperative complications were recorded. Component stability was assessed with weight-bearing radiographs. Clinical evaluation included range of motion (ROM) tests using a goniometer and under fluoroscopy using a lateral view. Clinical outcomes were analysed by a visual analogue scale, the American Orthopaedic Foot and Ankle Society hindfoot score and Short Form (36) Health Survey (SF-36) health survey. One patient sustained an intraoperative medial malleolar fracture. In two patients delayed wound healing was observed. Two secondary major surgeries were performed. Pain level decreased from 8.2 ± 0.9 (range = 7-10) preoperatively to 1.1 ± 1.2 (range = 0-4) postoperatively. Significant functional improvement including ROM was observed. All categories of SF-36 score showed significant improvement in quality of life. Mid-term results of TAR in patients with VWD are encouraging. The total rate of intraoperative and postoperative complications was 33.3%. However, longer term outcomes are necessary to fully understand the clinical benefit of TAR in patients with VWD.

Characterization of the collagen component of cartilage repair tissue of the talus with quantitative MRI: comparison of T2 relaxation time measurements with a diffusion-weighted double-echo steady-state sequence (dwDESS).

OBJECTIVES: The purpose of this study was to characterize the collagen component of repair tissue (RT) of the talus after autologous matrix-induced chondrogenesis (AMIC) using quantitative T2 and diffusion-weighted imaging. METHODS: Mean T2 values and diffusion coefficients of AMIC-RT and normal cartilage of the talus of 25 patients with posttraumatic osteochondral lesions and AMIC repair were compared in a cross-sectional design using partially spoiled steady-state free precession (pSSFP) for T2 quantification, and diffusion-weighted double-echo steady-state (dwDESS) for diffusion measurement. RT and cartilage were graded with modified Noyes and MOCART scores on morphological sequences. An association between follow-up interval and quantitative MRI measures was assessed using multivariate regression, after stratifying the cohort according to time interval between surgery and MRI. RESULTS: Mean T2 of the AMIC-RT and cartilage were 43.1 ms and 39.1 ms, respectively (p = 0.26). Mean diffusivity of the RT (1.76 µm(2)/ms) was significantly higher compared to normal cartilage (1.46 µm(2)/ms) (p = 0.0092). No correlation was found between morphological and quantitative parameters. RT diffusivity was lowest in the subgroup with follow-up >28 months (p = 0.027). CONCLUSIONS: Compared to T2-mapping, dwDESS demonstrated greater sensitivity in detecting differences in the collagen matrix between AMIC-RT and cartilage. Decreased diffusivity in patients with longer follow-up times may indicate an increased matrix organization of RT. KEY POINTS: • MRI is used to assess morphology of the repair tissue during follow-up. • Quantitative MRI allows an estimation of biochemical properties of the repair tissue. • Differences between repair tissue and cartilage were more significant with dwDESS than T2 mapping.

[Total ankle replacement in patients with bleeding disorders]. / Endoprothetischer Ersatz des oberen Sprunggelenks bei Patienten mit Gerinnungsstörungen.

BACKGROUND: Total ankle replacement (TAR) is a well-accepted treatment option in patients with end-stage ankle osteoarthritis. However, published literature on patients with bleeding disorders treated with TAR is limited. Therefore, we carried out this prospective study to analyze mid-term postoperative results in patients with bleeding disorders treated by TAR. METHODS: A total of 34 patients with end-stage ankle osteoarthritis--14 patients with hemophilia type A and 20 patients with von Willebrand disease (VWD)--treated by TAR were included in this prospective study. The mean age of patients was 46.0 ± 9.0 years. Intraoperative and postoperative complications were recorded. The postoperative pain relief and functional results including range of motion (ROM) and American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score were assessed after a mean follow-up of 6.3 ± 3.4 years. Additionally, the quality of life was analyzed using the SF-36 questionnaire. The alignment of prosthesis components was assessed using weight-bearing conventional radiographs. The results were compared with those obtained in the control group, including 72 and 33 patients with post-traumatic and rheumatoid ankle osteoarthritis respectively. RESULTS: One patient sustained an intraoperative medial malleolar fracture. In total, three revision surgeries were necessary in our patient cohort. There was significant pain relief from 8.2 ± 0.8 to 0.9 ± 1.0, as assessed using a visual analog scale. All categories of the SF-36 score showed significant improvement. The average ROM increased from 20.1° ± 6.9° to 27.5° ± 7.4°. The AOFAS hindfoot score increased from 34.5 ± 10.0 to 82.4 ± 10.2 of a maximum of 100 points. Radiographic assessment showed the neutral alignment of prosthesis components in all patients. The postoperative clinical and radiographic outcomes were comparable in both patients with hemophilia and those with VWD. Patients with bleeding disorders had significantly higher pain relief and significantly lower ROM than the patients in the control group with ankle osteoarthritis of post-traumatic or rheumatoid etiology. CONCLUSION: Our prospective study revealed encouraging mid-term outcomes after TAR in patients with bleeding disorders. However, this surgery should be limited to highly experienced foot and ankle surgeons. Furthermore, this patient cohort requires a multidisciplinary approach to ensure a good outcome.

Effect of muscle weakness and joint inflammation on the onset and progression of osteoarthritis in the rabbit knee.

OBJECTIVES: Interactions between mechanical and non-mechanical independent risk factors for the onset and progression of Osteoarthritis (OA) are poorly understood. Therefore, the goal of the present study was to investigate the in vivo effects of muscle weakness, joint inflammation and the combination on the onset and progression of OA in a rabbit knee joint model. MATERIALS AND METHODS: Thirty 1-year-old female New Zealand White rabbits (average 5.7 kg, range 4.8-6.6 kg) were divided into four groups with one limb randomly assigned to be the experimental side: (1) surgical denervation of the vastus lateralis (VL) muscle; (2) muscle weakness induced by intramuscular injection of Botulinum toxin A (BTX-A); (3) intraarticular injection with Carrageenan to induce a transient inflammatory reaction; (4) combination of Carrageenan and BTX-A injection. After 90 days, cartilage histology of the articular surfaces were microscopically analyzed using the Osteoarthritis Research Society International (OARSI) histology scoring system. RESULTS: VL denervation resulted in significantly higher OARSI scores in the patellofemoral joint (group 1). BTX-A administration resulted in significant cartilage damage in all four compartments of the knee (group 2). Carrageenan did not cause significant cartilage damage. BTX-A combined with Carrageenan lead to severe cartilage damage in all four compartments. CONCLUSION: Muscle weakness lead to significant OA in the rabbit knee. A transient local inflammatory stimulus did not promote cartilage degradation nor did it enhance OA progression when combined with muscle weakness. These results are surprising and add to the literature the conclusion that acute inflammation is probably not an independent risk factor for OA in this rabbit model.

[Treatment of isolated fractures of the olecranon: percutaneous double-screw fixation versus conventional tension band wiring]. / Behandlung von isolierten Olekranonfrakturen: Perkutane Doppelschraubenosteosynthese vs. konventionelle Zuggurtung.

BACKGROUND: Isolated fractures of the olecranon account for 7-10% of all osseous injuries in adults. These fractures are usually treated surgically by conventional tension band wiring. The percutaneous double-screw fixation is an optional treatment in patients with two fragment olecranon fractures with some postoperative advantages. PATIENTS AND METHODS: A total of 13 patients with isolated fractures of the olecranon (Schatzker-Schmelling type A) treated by percutaneous double-screw fixation were included in this prospective study. The mean age of patients was 43.6 ± 11.0 years. Intraoperative and postoperative complications were recorded. Functional results were assessed after a mean follow-up of 38.2 ± 11.5 months using the Quick-DASH score. The results were compared with those obtained in the control group including 26 patients treated by conventional tension band wiring. RESULTS: No intraoperative complications were observed in both groups. In the group with percutaneous double-screw fixation the scar length was significantly shorter (2.4 ± 0.4 cm vs. 11.0 ± 1.8 cm, p < 0.001) and the hardware removal was substantially less frequent that in the group with conventional tension band wiring with 38.5 % and 73.1 %, respectively. At the minimum follow-up of 2 years comparable functional results were obtained in both groups (Quick-DASH score 2.3 vs. 0.0 points, respectively, p = 0.155); however, the range of elbow motion was significantly higher in the group with percutaneous double-screw fixation (extension/flexion 145° vs. 130°, p < 0.001; pronation/supination 165° vs. 155°, p < 0.001). CONCLUSIONS: The percutaneous double-screw fixation is a safe and viable treatment option in patients with isolated fractures of the olecranon (Schatzker-Schmelling type A). The functional results regarding DASH scores obtained using this technique were comparable with those observed in patients with conventional tension band wiring; however, range of elbow motion and cosmetic results were significantly better in the patient group with percutaneous double-screw fixation.

Delayed gadolinium-enhanced MRI of cartilage of the ankle joint: results after autologous matrix-induced chondrogenesis (AMIC)-aided reconstruction of osteochondral lesions of the talus.

AIM: To assess cartilage quality using delayed gadolinium-enhanced magnetic resonance imaging after repair of osteochondral lesions of the talus using autologous matrix-induced chondrogenesis (AMIC). MATERIALS AND METHODS: A three-dimensional (3D) spoiled gradient-echo (SGE) sequence at 3 T was used to obtain quantitative T1 relaxation times before and after Gd-DTPA2 (Magnevist, 0.2 mM/kg bod weight) administration to assess 23 cases of AMIC-aided repair of osteochondral lesions of the talus. Delta relaxation rates (ΔR1) for reference cartilage (RC) and repair tissue (RT), and the relative delta relaxation rate (rΔR1) were calculated. The morphological appearance of the cartilage RT was graded on sagittal dual-echo steady-state (DESS) views according to the "magnetic resonance observation of cartilage repair tissue" (MOCART) protocol. The study was approved by the institutional review board and written consent from each patient was obtained. RESULTS: The AMIC cases had a mean T1 relaxation time of 1.194 s (SD 0.207 s) in RC and 1.470 s (SD 0.384 s) in RT before contrast medium administration. The contrast-enhanced T1 relaxation time decreased to 0.480 s (SD 0.114 s) in RC and 0.411 s (SD 0.096 s) in RT. There was a significant difference (p > 0.05) between the ΔR1 in RC (1.372 × 10(-3)/s, range 0.526-3.201 × 10(-3)/s, SD 0.666 × 10(-3)/s) and RT (1.856 × 10(-3)/s, range 0.93-3.336 × 10(-3)/s, SD 0.609 × 10(-3)/s). The mean rΔR1 was 1.49, SD 0.45). The mean MOCART score at follow-up was 62.6 points (range 30-95, SD 15.3). CONCLUSION: The results of the present study suggest that repair cartilage resulting from AMIC-aided repair of osteochondral lesions of the talus has a significantly lower glycosaminoglycan (GAG) content than normal hyaline cartilage, but can be regarded as having hyaline-like properties.

[Malleolar osteotomy--osteotomy as approach]. / Knöchelosteotomie--Die Osteotomie als Zugang.

Both arthroscopic and open surgical techniques may be used for treatment of osteochondral lesions of the ankle joint. Osteotomy around the ankle joint is a well established technique to extend the approach in cases where the osteochondral lesions are located more posteriorly. Medial, oblique, monoplanar malleolar osteotomy should be used in patients with lesions of the medial talus shoulder. The posterolateral ostechondral lesions are less frequent and in such cases distal fibular osteotomy is recommended. In this study the indications for different forms of osteotomy are discussed and the surgical techniques are described.

[Thromboembolic complications following ankle prosthesis implantation]. / Thrombembolische Komplikationen nach Sprunggelenkprothesenimplantation.

BACKGROUND: Total ankle replacement is becoming an increasingly used treatment for patients with degenerative arthritis of the ankle; however, there is limited literature available addressing the incidence of thromboembolic complications after total ankle replacement. Therefore, we performed a systematic literature review addressing thrombosis prophylaxis and incidence of thromboembolic complications after total ankle replacement. Furthermore, we evaluated the incidence of thromboembolic complications in our clinic. METHODS: A systemic literature review was performed using established medical literature data bases. The following information was retrieved from the literature: thrombosis prophylaxis and duration and deep vein thrombosis/pulmonary embolism as postoperative complication. The incidence of thromboembolic complications was evaluated in our patient cohort including 964 total ankle replacement procedures. RESULTS: A total of 21 clinical studies were included in the systematic literature review. The range of incidence of thromboembolic complications was between 0.0 % and 4.8 %. In our patient cohort the incidence of symptomatic deep vein thrombosis was 3.4 %. There were no cases of pulmonary embolism. All patients received low molecular weight heparin prophylaxis. CONCLUSION: The incidence of thromboembolic complications in our patient cohort was comparable to that of symptomatic deep vein thrombosis in patients undergoing total knee or hip replacement or ankle fusion. We suggest the prophylactic use of low molecular weight heparin for patients after total ankle replacement.

Tissue engineering approaches to degenerative disc disease--a meta-analysis of controlled animal trials.

OBJECTIVE: The objective of this systematic review was to assess cell/biomaterial treatments of degenerative disc disease in controlled animal trails. The primary endpoints were restoration of disc height and T2 signal intensity. METHOD: PubMed, CINAHL, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), and Cochrane Database of Systematic Reviews (CDSR) were searched for studies reporting on the use of tissue engineering treatments (cells/biomaterials/cells and biomaterials) for degenerative disc disease treatments in a controlled trial. Publication bias was assessed graphically using funnel plots and Egger's regression. Data were grouped by follow-up duration - early (<4 weeks), intermediate (4-12 weeks) and late (>12 weeks), and weighted mean differences (WMD) were calculated using DerSimonian-Laird Random Effect models. RESULTS: Thirteen papers, published between 2004 and 2011, were included in this study. In comparison with the injured disc, all three treatments showed a positive effect in disc height, but none of the treatments restored disc height compared to the healthy disc. Overall, there seemed to be a better effect on disc height restoration for the treatment with cells and biomaterials. None of the treatments could achieve the same T2 signal intensity as the healthy disc, and compared to the injured disc, only the treatment with cells and biomaterials showed consistently better results. CONCLUSION: Treatment of an injured/degenerating disc with cells, cells plus biomaterial or biomaterial alone has a potential for at least a partial regeneration of the disc. However, so far, none of the treatments is able to effectively restore the properties of a healthy disc.

[Total ankle arthroplasty in valgus ankle osteoarthritis]. / Sprunggelenkprothese bei Valgusarthrose.

Ankle osteoarthritis (OA) is often associated with deformities. Valgus OA is less frequent than varus OA and causes of valgus OA include medial ligament instability, flat foot and posttraumatic situations, e.g. fractures of the fibula or lateral tibial plafond. The importance of the mechanical axis is generally accepted in orthopedic surgery. In cases of implantation of total ankle replacements the normal biomechanics need to be restored in order to have a correct and pain-free functioning total ankle replacement both in the short and long-term. The two most important criteria are (1) an anterior tibio-talar angle of about 90° and (2) a neutral hindfoot position. The hindfoot position is measured with the hindfoot alignment view according to Saltzman. In this view, healthy feet are in neutral or minimal varus position of 1-2° and not in a valgus position as generally assumed. The following operative steps are performed depending on the degree and localization of the valgus deformity: (1) total ankle replacement, (2) supramalleolar or (3) inframalleolar osteotomy/arthrodesis, (4) medial ligament repair, (5) fibula osteotomy and (6) syndesmotic reconstruction.

Painful flatfoot deformity.

The posterior tibial muscle is the key dynamic support of the medial longitudinal arch of the foot. When it fails--typically in women older than 40 years of age--progressively, the arch slowly collapses, the heel drifts into valgus, the midfoot flattens, and the forefoot gradually abducts and supinates, resulting in painful acquired pes planovalgus abductus et supinatus. Posterior tibial tendon insufficiency (PTTI) is often misdiagnosed as a chronic ankle sprain, osteoarthritis, or collapsed arch as a result of aging or obesity, and it leaves the patient debilitated. Prompt diagnosis prevents frustration for the patient and allows treatment to be started at an earlier, more easily managed stage. The diagnosis of PTTI is largely a clinical one. An increased awareness of the existence of PTTI should serve to help patients with earlier referral and treatment and by limiting the amount of disability.

Are ankle chondrocytes from damaged fragments a suitable cell source for cartilage repair?

OBJECTIVE: To characterize the post-expansion cartilage-forming capacity of chondrocytes harvested from detached fragments of osteochondral lesions (OCLs) of ankle joints (Damaged Ankle Cartilage Fragments, DACF), with normal ankle cartilage (NAC) as control. DESIGN: DACF were obtained from six patients (mean age: 35 years) with symptomatic OCLs of the talus, while NAC were from 10 autopsies (mean age: 55 years). Isolated chondrocytes were expanded for two passages and then cultured in pellets for 14 days or onto HYAFF-11 meshes (FAB, Italy) for up to 28 days. Resulting tissues were assessed histologically, biochemically [glycosaminoglycan (GAG), DNA and type II collagen (CII)] and biomechanically. RESULTS: As compared to NAC, DACF contained significantly lower amounts of DNA (3.0-fold), GAG (5.3-fold) and CII (1.5-fold) and higher amounts of type I collagen (6.2-fold). Following 14 days of culture in pellets, DACF-chondrocytes generated tissues less intensely stained for Safranin-O and CII, with significantly lower GAG contents (2.8-fold). After 28 days of culture onto HYAFF((R))-11, tissues generated by DACF-chondrocytes were less intensely stained for Safranin-O and CII, contained significantly lower amounts of GAG (1.9-fold) and CII (1.4-fold) and had lower equilibrium (1.7-fold) and dynamic pulsatile modulus (3.3-fold) than NAC-chondrocytes. CONCLUSION: We demonstrated that DACF-chondrocytes have inferior cartilage-forming capacity as compared to NAC-chondrocytes, possibly resulting from environmental changes associated with trauma/disease. The study opens some reservations on the use of DACF-derived cells for the repair of ankle cartilage defects, especially in the context of tissue engineering-based approaches.

Does alignment in the hindfoot radiograph influence dynamic foot-floor pressures in ankle and tibiotalocalcaneal fusion?

BACKGROUND: The Saltzman-el-Khoury hindfoot alignment view (HAV) is considered the gold standard for assessing the axis from hindfoot to tibia. However, it is unclear whether radiographic alignment influences dynamic load distribution during gait. QUESTIONS/PURPOSES: We evaluated varus-valgus alignment by the HAV and its influence on dynamic load distribution in ankle and tibiotalocalcaneal (TTC) arthrodesis. PATIENTS AND METHODS: We clinically assessed 98 patients (ankle, 56; TTC, 42) with SF-36 and American Orthopaedic Foot and Ankle Society (AOFAS) scores, visual hindfoot alignment, HAV angle, and dynamic pedobarography using a five-step method. For comparison, 70 normal feet were evaluated. Minimum followup was 2 years (average, 4.11 years; range, 2-6 years). RESULTS: The mean HAV angle was -0.8° ± 7.8° for ankle and -1.2° ± 6.9° for TTC arthrodesis. The HAV angle correlated with pedobarographic load distribution (r = 0.35-0.53). Radiographic alignment did not influence SF-36 or AOFAS scores; however, load distribution correlated to qualities of these scores. Visual alignment only predicted the corresponding HAV angle in 48%. To reproduce the dynamic load of healthy subjects, HAV angles of 5° to 10° valgus were needed. CONCLUSIONS: Visual positioning is inadequate to determine intraoperative positioning and resulted in a varus position with a relatively large SD. The HAV should be used to assess the hindfoot alignment correctly. HAV angles of 5° to 10° valgus are needed to reproduce a physiologic gait pattern.

Frontal and lateral characteristics of the osseous configuration in chronic ankle instability.

OBJECTIVE: The osseous ankle configuration (tibiotalar sector, talar radius and height) has been discovered as intrinsic risk factor for chronic ankle instability (CAI). These measurements were done on lateral radiographs only. In this study, the osseous characteristics in the frontal plane and further lateral values were measured. DESIGN: Level III case-control study. SETTING: Radiological measurement of frontal and lateral radiographs by one independent, blinded radiologist using a digital DICOM/PACS system. PATIENTS: A group of 52 patients with CAI was compared with an age- and sex-matched control group of 52 healthy subjects. MAIN OUTCOME MEASUREMENTS: In the frontal plane, the depth of the talar curvature (frontal curvature (froCu)) and the lateral and medial malleolar lengths were measured. In the lateral plane, the position of the centre of rotation to the tibial axis (talar centre of rotation to the anatomical axis of the tibia (TibCOR)) and the tibial lateral surface angle (TLS) were also measured. RESULTS: The froCu was deeper in patients with CAI (1.8 (0.5) mm) than in healthy subjects (1.0 (0.5) mm, p<0.05). The TibCOR was more anterior in patients with CAI (2.5 (1.9) mm) than in healthy subjects (1.6 (2.2) mm, p<0.05). The distance from the fibular tip to the centre of rotation was smaller in patients with CAI (3.5 (3.4) mm) than in healthy subjects (6.5 (3.3) mm, p<0.05). The TLS and the length of the lateral and medial ankle were not significantly different. CONCLUSIONS: This study supports that the osseous joint configuration is an intrinsic risk factor for CAI. It could be shown that CAI is characterised by a deeper frontal curvature of the talus and a more anterior position of the talus to the tibia.

[Achilles tendon ruptures and tibialis anterior tendon ruptures]. / Achillessehnen- und Tibialis-anterior-Sehnenruptur.

Achilles tendon ruptures (ATR) are becoming the most frequent tendon rupture of the lower extremity, whereas less than 100 cases of tibialis anterior tendon ruptures (TATR) have been reported. Common in both tendons are the degenerative causes of ruptures in a susceptible tendon segment, whereas traumatic transections occur at each level. Triceps surae and tibialis anterior muscles are responsible for the main sagittal ankle range of motion and ruptures lead to a distinctive functional deficit. However, diagnosis is delayed in up to 25% of ATR and even more frequently in TATR. Early primary repair provides the best functional results. With progressive retraction and muscle atrophy delayed tendon reconstruction has less favourable functional results. But not all patients need full capacity, power and endurance of these muscles and non-surgical treatment should not be forgotten. Inactive patients with significant comorbidities and little disability should be informed that surgical treatment of TATR is complicated by high rates of rerupture and surgical treatment of ATR can result in wound healing problems rarely necessitating some kind of transplantation.

A novel implantation technique for engineered osteo-chondral grafts.

We present a novel method to support precise insertion of engineered osteochondral grafts by pulling from the bone layer, thereby minimizing iatrogenic damage associated with direct manipulation of the cartilage layer. Grafts were generated by culturing human expanded chondrocytes on Hyaff-11 meshes, sutured to Tutobone spongiosa cylinders. Through the bone layer, shaped to imitate the surface-contours of the talar dome, two sutures were applied: the first for anterograde implantation, to pull the graft into the defect, and the second for retrograde correction, in case of a too deep insertion. All grafts could be correctly positioned into osteochondral lesions created in cadaveric ankle joints with good fit to the surrounding cartilage. Implants withstood short-term dynamic stability tests applied to the ankle joint, without delamination or macroscopic damage. The developed technique, by allowing precise and stable positioning of osteochondral grafts without iatrogenic cartilage damage, is essential for the implantation of engineered tissues, where the cartilage layer is not fully mechanically developed, and could be considered also for conventional autologous osteochondral transplantation.

[Calcaneal fractures: controversies and consensus]. / Fracturas de calcáneo: controversias y consensos.

Calcaneal fractures are the most common tarsal fractures and their treatment is still debated today. We intend in this update to highlight the points of controversy and clarify the consensus, especially in the treatment of intra-articular fractures, as well as to describe the management of major complications.

Las fracturas de calcáneo son las más frecuentes del tarso y su tratamiento sigue siendo hoy en día objeto de debate. Pretendemos en esta actualización destacar los puntos de controversia, así como clarificar los consensos, especialmente en el tratamiento de las fracturas intraarticulares, así como describir el manejo de las principales complicaciones.