[Medial foot and ankle instability]. / Mediale Fuß- und Sprunggelenkinstabilitäten.

The deltoid or medial collateral ligament consisting of superficial and deep components together with the spring ligament is the primary stabilizer of the ankle joint. Injuries of these anatomical structures are more frequent than assumed but are nevertheless often overlooked. Inadequate treatment can lead to chronic pain, instability, hindfoot deformities and ankle arthritis. Patient history and clinical assessment can help to identify injuries of the deltoid ligament. Magnetic resonance imaging (MRI) is the diagnostic method of choice. Arthroscopy of the ankle joint can be a valuable tool in the assessment of the injury. Treatment should include accompanying injuries and deformities and can range from immobilization in a cast to ligament repair up to ligament reconstruction using a free tendon graft.

[Total ankle replacement for varus deformity]. / Sprunggelenkprothese bei Varusarthrose.

Coronal plane deformity has been found to be one of the main risk factors for poor clinical results, higher complication rates and failure of total ankle replacements. Initially, many authors considered a malalignment of more than 10° to be a contraindication for total ankle replacement, however, several publications later underlined the usefulness of the distinction of different etiologies of hindfoot malalignment. This subsequently led to suggestions for additional procedures in order to avoid early implant failure.The aim of the present article is to illustrate the different causes of varus malaligned arthritic ankles and to present procedures to balance these ankles at the time of replacement.

[Revision arthroplasty of the ankle joint]. / Revisionsarthroplastik des oberen Sprunggelenks.

In the last 20 years total ankle replacement has become a viable alternative to arthrodesis for end-stage osteoarthritis of the ankle. Numerous ankle prosthesis designs have appeared on the market in the past and attracted by the encouraging intermediate results reported in the literature, many surgeons have started to perform this procedure. With increased availability on the market the indications for total ankle replacement have also increased in recent years. In particular, total ankle replacement may now be considered even in younger patients. Therefore, despite progress in total ankle arthroplasty the number of failures may increase. Up to now, arthrodesis was considered to be the gold standard for salvage of failed ankle prostheses. Because of extensive bone loss on the talar side, in most instances tibiocalcaneal fusion is the only reliable solution. An alternative to such extended hindfoot fusions would be revision arthroplasty. To date, however, there are no reported results of revision arthroplasty for salvage of a failed ankle replacement.Based on our experience prosthetic components with a flat undersurface are most likely to be able to find solid support on remaining bone stock. The first 83 cases (79 patients, 46 males, 33 females, average age 58.9 years, range 30.6-80.7 years) with a average follow-up of 5.4 years (range 2-11 years) showed excellent to good results in 69 cases (83%), a satisfactory result in 12 cases (15%) and a fair result in 2 cases (2%) and 47 patients (56%) were pain free. Primary loosening was noted in three cases and of these two cases were successfully revised by another total ankle replacement and in one case with arthrodesis. Another case with hematogenous infection was also revised by arthrodesis. At the last follow-up control two components were considered to be loose and the overall loosening rate was thus 6%.This series has proven that revision arthroplasty can be a promising option for patients with failed total ankle prosthesis. The most challenging issue is the solid anchoring of available components on residual bone. More experience is needed, however, to better define the possibilities and limitations of revision arthroplasty.

[Medial pain syndrome in patients with total ankle replacement]. / Mediales Schmerzsyndrom nach Sprunggelenkprothesenimplantation.

Total ankle replacement is an increasingly recommended treatment for patients with end-stage ankle osteoarthritis. The increasing experience with this procedure explains its acceptance as a therapeutic option in complex cases as part of reconstruction surgery. However, the complication rate including failure of the prosthesis should not be underestimated. Previous studies have shown that most patients developed ankle osteoarthritis secondary to previous trauma. Patients with posttraumatic osteoarthritis often have varus or valgus misalignment of the hindfoot. In cases with incorrectly addressed hindfoot misalignment and/or incorrectly positioned prosthesis components, pain may remain postoperatively because of biomechanical dysbalance and asymmetrical load. The pain is mostly localized on the medial side the so-called medial pain syndrome.The following classification of the medial pain syndrome has been established in our practice: type I medial impingement/contracture of medial ligaments, type II valgus deformity, type III varus deformity, type IV combined varus-valgus deformity.

[Injuries and dysfunction of the posterior tibial tendon]. / Verletzungen und Funktionsstörungen der Tibialis-posterior-Sehne.

The function of the posterior tibial (PT) tendon is to stabilize the hindfoot against valgus and eversion forces. It functions as the primary invertor of the foot and assists the Achilles tendon in plantar flexion. The PT tendon is a stance phase muscle, firing from heel strike to shortly after heel lift-off. It decelerates subtalar joint pronation after heel contact. It functions as a powerful subtalar joint supinator and as a support of the medial longitudinal arch. The action of the tendon travels to the transverse tarsal joints, locking them and allowing the gastrocnemius to support heel rise. Acute injuries of the PT tendon are rare and mostly affect the active middle-aged patient or they are the result of complex injuries to the ankle joint complex. Dysfunction of the PT tendon following degeneration and rupture, in contrast, has shown an increasing incidence in recent years. To which extent changed lifestyle, advancing age, comorbidities, and obesity play a role has not yet been clarified in detail. Dysfunction of the PT tendon results in progressive destabilization of the hind- and midfoot. Clinically, the ongoing deformation of the foot can be classified into four stages: in stage 1, the deformity is distinct and fully correctable; in stage II, the deformity is obvious, but still correctable; in stage III, the deformity has become stiff; and in stage IV, the ankle joint is also involved in the deformity. Treatment modalities depend on stage: while conservative measures may work in stage I, surgical treatment is mandatory for the later stages. Reconstructive surgery is advised in stage II, whereas in stage III and IV correcting and stabilizing arthrodeses are advised. A promising treatment option for stage IV may be adding an ankle prosthesis to a triple arthrodesis, as long as the remaining competence of the deltoid ligament is sufficient. An appropriate treatment is mandatory to avoid further destabilization and deformation of the foot. Failures of treatment result mostly from underestimation of the problem or insufficient treatment of existing instability and deformity.

[Treatment of acute and chronic peroneal tendon disorders]. / Behandlung akuter und chronischer Verletzungen der Peronäalsehnen.

Peroneal tendon injuries are recognized with increasing frequency to be the cause of persistent lateral ankle symptoms. The lesions are frequently found in patients with concomitant anatomical or biomechanical abnormalities, such as chronic lateral instability or cavovarus deformity. The most common mechanism involves a sudden inversion injury or repetitive activities. Three categories of injuries can be distinguished: (1) tendinitis and tenosynovitis, (2) tendon subluxation and dislocation and (3) tendon tears and ruptures. Many of these conditions respond to conservative therapy. However, when left untreated, the disorders can lead to persistent lateral ankle pain and substantial functional deficits. This is particularly true in patients with an underlying anatomical predisposition to lesions.

A computer touch-screen version of the North American Spine Society outcome assessment instrument for the lumbar spine.

We validated the North American Spine Society (NASS) outcome-assessment instrument for the lumbar spine in a computerised touch-screen format and assessed patients' acceptance, taking into account previous computer experience, age and gender. Fifty consecutive patients with symptomatic and radiologically-proven degenerative disease of the lumbar spine completed both the hard copy (paper) and the computerised versions of the NASS questionnaire. Statistical analysis showed high agreement between the paper and the touch-screen computer format for both subscales (intraclass correlation coefficient 0.94, 95% confidence interval (0.90 to 0.97)) independent of computer experience, age and gender. In total, 55% of patients stated that the computer format was easier to use and 66% preferred it to the paper version (p < 0.0001 among subjects expressing a preference). Our data indicate that the touch-screen format is comparable to the paper form. It may improve follow-up in clinical practice and research by meeting patients' preferences and minimising administrative work.

Osteoligamentous injuries of the medial ankle joint.

Injuries of the ankle joint have a high incidence in daily life and sports, thus, playing an important socioeconomic role. Therefore, proper diagnosis and adequate treatment are mandatory. While most of the ligament injuries around the ankle joint are treated conservatively, great controversy exists on how to treat deltoid ligament injuries in ankle fractures. Missed injuries and inadequate treatment of the medial ankle lead to inferior outcome with instability, progressive deformity, and ankle joint osteoarthritis.

Treatment of extended osteochondral lesions of the talus with a free vascularised bone graft from the medial condyle of the femur.

Large osteochondral lesions (OCLs) of the shoulder of the talus cannot always be treated by traditional osteochondral autograft techniques because of their size, articular geometry and loss of an articular buttress. We hypothesised that they could be treated by transplantation of a vascularised corticoperiosteal graft from the ipsilateral medial femoral condyle. Between 2004 and 2011, we carried out a prospective study of a consecutive series of 14 patients (five women, nine men; mean age 34.8 years, 20 to 54) who were treated for an OCL with a vascularised bone graft. Clinical outcome was assessed using a visual analogue scale (VAS) for pain and the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score. Radiological follow-up used plain radiographs and CT scans to assess graft incorporation and joint deterioration. At a mean follow-up of 4.1 years (2 to 7), the mean VAS for pain had decreased from 5.8 (5 to 8) to 1.8 (0 to 4) (p = 0.001) and the mean AOFAS hindfoot score had increased from 65 (41 to 70) to 81 (54 to 92) (p = 0.003). Radiologically, the talar contour had been successfully reconstructed with stable incorporation of the vascularised corticoperiosteal graft in all patients. Joint degeneration was only seen in one ankle. Treatment of a large OCL of the shoulder of the talus with a vascularised corticoperiosteal graft taken from the medial condyle of the femur was found to be a safe, reliable method of restoring the contour of the talus in the early to mid-term.

Mid- to long-term outcome of 96 corrective hindfoot fusions in 84 patients with rigid flatfoot deformity.

Talonavicular and subtalar joint fusion through a medial incision (modified triple arthrodesis) has become an increasingly popular technique for treating symptomatic flatfoot deformity caused by posterior tibial tendon dysfunction. The purpose of this study was to look at its clinical and radiological mid- to long-term outcomes, including the rates of recurrent flatfoot deformity, nonunion and avascular necrosis of the dome of the talus. A total of 84 patients (96 feet) with a symptomatic rigid flatfoot deformity caused by posterior tibial tendon dysfunction were treated using a modified triple arthrodesis. The mean age of the patients was 66 years (35 to 85) and the mean follow-up was 4.7 years (1 to 8.3). Both clinical and radiological outcomes were analysed retrospectively. In 86 of the 95 feet (90.5%) for which radiographs were available, there was no loss of correction at final follow-up. In all, 14 feet (14.7%) needed secondary surgery, six for nonunion, two for avascular necrosis, five for progression of the flatfoot deformity and tibiotalar arthritis and one because of symptomatic overcorrection. The mean American Orthopaedic Foot and Ankle Society Hindfoot score (AOFAS score) at final follow-up was 67 (between 16 and 100) and the mean visual analogue score for pain 2.4 points (between 0 and 10). In conclusion, modified triple arthrodesis provides reliable correction of deformity and a good clinical outcome at mid- to long-term follow-up, with nonunion as the most frequent complication. Avascular necrosis of the talus is a rare but serious complication of this technique.

The treatment and outcome of peri-prosthetic infection of the ankle: a single cohort-centre experience of 34 cases.

The treatment of peri-prosthetic joint infection (PJI) of the ankle is not standardised. It is not clear whether an algorithm developed for hip and knee PJI can be used in the management of PJI of the ankle. We evaluated the outcome, at two or more years post-operatively, in 34 patients with PJI of the ankle, identified from a cohort of 511 patients who had undergone total ankle replacement. Their median age was 62.1 years (53.3 to 68.2), and 20 patients were women. Infection was exogenous in 28 (82.4%) and haematogenous in six (17.6%); 19 (55.9%) were acute infections and 15 (44.1%) chronic. Staphylococci were the cause of 24 infections (70.6%). Surgery with retention of one or both components was undertaken in 21 patients (61.8%), both components were replaced in ten (29.4%), and arthrodesis was undertaken in three (8.8%). An infection-free outcome with satisfactory function of the ankle was obtained in 23 patients (67.6%). The best rate of cure followed the exchange of both components (9/10, 90%). In the 21 patients in whom one or both components were retained, four had a relapse of the same infecting organism and three had an infection with another organism. Hence the rate of cure was 66.7% (14 of 21). In these 21 patients, we compared the treatment given to an algorithm developed for the treatment of PJI of the knee and hip. In 17 (80.9%) patients, treatment was not according to the algorithm. Most (11 of 17) had only one criterion against retention of one or both components. In all, ten of 11 patients with severe soft-tissue compromise as a single criterion had a relapse-free survival. We propose that the treatment concept for PJI of the ankle requires adaptation of the grading of quality of the soft tissues.

Corrective supramalleolar osteotomy for malunited pronation-external rotation fractures of the ankle.

We undertook a prospective study to analyse the outcome of 48 malunited pronation-external rotation fractures of the ankle in 48 patients (25 females and 23 males) with a mean age of 45 years (21 to 69), treated by realignment osteotomies. The interval between the injury and reconstruction was a mean of 20.2 months (3 to 98). In all patients, valgus malalignment of the distal tibia and malunion of the fibula were corrected. In some patients, additional osteotomies were performed. Patients were reviewed regularly, and the mean follow-up was 7.1 years (2 to 15). Good or excellent results were obtained in 42 patients (87.5%) with the benefit being maintained over time. Congruent ankles without a tilted talus (Takakura stage 0 and 1) were obtained in all but five cases. One patient required total ankle replacement.

[Modified Lambrinudi arthrodesis with additional posterior tibial tendon transfer in adult drop foot]. / Modifizierte Arthrodese nach Lambrinudi mit zusätzlichem Transfer der Tibialis-posterior-Sehne zur Behandlung des adulten Fallfußes.

OBJECTIVE: Treatment of adult instable drop foot by modified Lambrinudi arthrodesis (removal of a wedge between the talus and calcaneus), followed by a posterior tibial tendon transfer to the medial cuneiform in order to provide active dorsiflexion. INDICATIONS: Severe drop foot (of various etiologies) in combination with hindfoot instability. Sufficient function of the posterior tibial muscle. CONTRAINDICATIONS: Neurologic dysfunction of the posterior tibial muscle, infection of foot/hindfoot, Charcot arthropathy, and insufficient patient compliance. RELATIVE CONTRAINDICATIONS: Previous surgery of posterior tibial tendon, critical soft tissues/skin conditions, insufficient neurovascular conditions. SURGICAL TECHNIQUE: Lateral skin incision. Debridement of sinus tarsi and removal of the bifurcate ligament to expose the subtalar, calcaneocuboidal, and talonavicular joints. Resection of a bone wedge from the calcaneus and talus (25-30°) to correct the drop foot deformity. Cartilage removal from the calcaneocuboid joint. Debridement of both the talar head and the navicular to allow adequate fitting. After reduction (neutral dorsiflexion and 10° foot abduction), preliminary fixation with Kirschner wires. Final fixation with canulated screws (talonavicular, calcaneocuboidal, and subtalar joints). Medial skin incision at the navicular tuberositas to deattach the posterior tibial tendon with a bony fragment. The tendon stump is harvested 10 cm proximal to the tibiotalar joint. Small skin incision at the anterolateral aspect of the distal lower leg. The posterior tibial tendon is transferred through the interosseous membrane and reattached to the medial cuneiform with a screw. POSTOPERATIVE MANAGEMENT: Immobilization with a removable short leg cast for 2-4 days. Ambulation with full weightbearing in a cast for 8 weeks. Radiographic assessment 8 weeks postoperatively. After bony healing, mobilization in normal shoes is allowed. Intensive physiotherapy to train the dorsiflexion. RESULTS: The average correction of drop foot deformity was 18.7°. Active dorsiflexion increased significantly from 30° preoperatively to 10° postoperatively.

The role of the fibula in varus and valgus deformity of the tibia: a biomechanical study.

It has been suggested that a supramalleolar osteotomy can return the load distribution in the ankle joint to normal. However, due to the lack of biomechanical data, this supposition remains empirical. The purpose of this biomechanical study was to determine the effect of simulated supramalleolar varus and valgus alignment on the tibiotalar joint pressure, in order to investigate its relationship to the development of osteoarthritis. We also wished to establish the rationale behind corrective osteotomy of the distal tibia. We studied 17 cadaveric lower legs and quantified the changes in pressure and force transfer across the tibiotalar joint for various degrees of varus and valgus deformity in the supramalleolar area. We assumed that a supramalleolar osteotomy which created a varus deformity of the ankle would result in medial overload of the tibiotalar joint. Similarly, we thought that creating a supramalleolar valgus deformity would cause a shift in contact towards the lateral side of the tibiotalar joint. The opposite was observed. The restricting role of the fibula was revealed by carrying out an osteotomy directly above the syndesmosis. In end-stage ankle osteoarthritis with either a valgus or varus deformity, the role of the fibula should be appreciated and its effect addressed where appropriate.

Simultaneous bilateral versus unilateral total ankle replacement: a patient-based comparison of pain relief, quality of life and functional outcome.

The aim of this study was to compare the outcome of bilateral sequential total ankle replacement (TAR) with that of unilateral TAR. We reviewed 23 patients who had undergone sequential bilateral TAR under a single anaesthetic and 46 matched patients with a unilateral TAR. There were no significant pre-operative differences between the two groups in terms of age, gender, body mass index, American Society of Anaesthesiologists classification and aetiology of the osteoarthritis of the ankle. Clinical and radiological follow-up was carried out at four months, one and two years. After four months, patients with simultaneous bilateral TAR reported a significantly higher mean pain score than those with a unilateral TAR. The mean American Orthopaedic Foot and Ankle Society hindfoot score and short-form 36 physical component summary score were better in the unilateral group. However, this difference disappeared at the one-and two-year follow-ups. Bilateral sequential TAR under one anaesthetic can be offered to patients with bilateral severe ankle osteoarthritis. However, they should be informed of the long recovery period.

Total ankle replacement in association with hindfoot fusion: Outcome and complications.

We report the clinical and radiological outcome of total ankle replacement performed in conjunction with hindfoot fusion or in isolation. Between May 2003 and June 2008, 60 ankles were treated with total ankle replacement with either subtalar or triple fusion, and the results were compared with a control group of 288 ankles treated with total ankle replacement alone. After the mean follow-up of 39.5 months (12 to 73), the ankles with hindfoot fusion showed significant improvement in the mean visual analogue score for pain (p < 0.001), the mean American Orthopaedic Foot and Ankle Society score (p < 0.001), and the mean of a modified version of this score (p < 0.001). The mean visual analogue pain score (p = 0.304) and mean modified American Orthopaedic Foot and Ankle Society score (p = 0.119) were not significantly different between the hindfoot fusion and the control groups. However, the hindfoot fusion group had a significantly lower mean range of movement (p = 0.009) and a higher rate of posterior focal osteolysis (p = 0.04). Both groups showed various complications (p = 0.131) and failure occurring at a similar rate (p = 0.685). Subtalar or triple fusion is feasible and has minimal adverse effects on ankles treated with total ankle replacement up to midterm follow-up. The clinical outcome of total ankle replacement when combined with hindfoot fusion is comparable to that of ankle replacement alone. Thus, hindfoot fusion should be performed in conjunction with total ankle replacement when indicated.

Subtalar and talonavicular arthrodesis through a single medial approach for the correction of severe planovalgus deformity.

We describe a retrospective review of the clinical and radiological parameters of 32 feet in 30 patients (10 men and 20 women) who underwent correction for malalignment of the hindfoot with a modified double arthrodesis through a medial approach. The mean follow-up was 21 months (13 to 37). Fusion was achieved in all feet at a mean of 13 weeks (6 to 30). Apart from the calcaneal pitch angle, all angular measurements improved significantly after surgery. Primary wound healing occurred without complications. The isolated medial approach to the subtalar and talonavicular joints allows good visualisation which facilitated the reduction and positioning of the joints. It was also associated with fewer problems with wound healing than the standard lateral approach.

Long-term outcome after supination-external rotation type-4 fractures of the ankle.

We have compared the results at a mean follow-up of 13 years (11 to 14) of two groups of supination-external rotation type-4 fractures of the ankle, in one of which there was a fracture of the medial malleolus and in the other the medial deltoid ligament had been partially or completely ruptured. Of 66 patients treated operatively between 1993 and 1997, 36 were available for follow-up. Arthroscopy had been performed in all patients pre-operatively to assess the extent of the intra-articular lesions. The American Orthopaedic Foot and Ankle Society hind-foot score was used for clinical evaluation and showed a significant difference in both the total and the functional scores (p < 0.05), but not in those for pain or alignment, in favour of the group with a damaged deltoid ligament (p < 0.05). The only significant difference between the groups on the short-form 36 quality-of-life score was for bodily pain, again in favour of the group with a damaged deltoid ligament. There was no significant difference between the groups in the subjective visual analogue scores or in the modified Kannus radiological score. Arthroscopically, there was a significant difference with an increased risk of loose bodies in the group with an intact deltoid ligament (p < 0.005), although there was no significant increased risk of deep cartilage lesions in the two groups. At a mean follow-up of 13 years after operative treatment of a supination-external rotation type-4 ankle fracture patients with partial or complete rupture of the medial deltoid ligament tended to have a better result than those with a medial malleolar fracture.

[Osteotomies of the distal tibia and hindfoot for ankle realignment]. / Korrekturosteotomien am distalen Unterschenkel und Rückfuss

Asymmetric load of the ankle joint often results in degenerative disease. Although reconstructive surgery, including osteotomies above and beneath the tibiotalar joint, is possible, there are little data with respect to its evidence. This article presents general considerations for osteotomies around the osteoarthritic ankle and elaborates a rationale for the technical procedure. Additional measures for correcting the deformed and malaligned hindfoot are also elucidated. As a principle, opening-wedge and closing-wedge osteotomies are possible in one or more planes. In some instances, inframalleolar osteotomies are also necessary to achieve proper alignment of the foot. If present, imbalance of soft tissues, such as incompetence of ligaments and insufficiency of tendons, must also be addressed. Our results have shown that osteotomies above and beneath the ankle joint are able to correct deformities and incongruencies at the tibiotalar joint over the years, thus avoiding further cartilage wear. In some patients, the tibiotalar joint regained a regular joint space that can be attributed to potential regeneration of cartilage. In all but a few cases (<5%), arthrodesis or total ankle replacement has been successfully avoided. This benefit is even more important because mostly younger, active patients are involved, and long-term results after arthrodesis and total ankle replacement are critical. Therefore, our treatment strategy is to correct the deformity first to achieve a well-aligned and balanced tibiotalar joint. If necessary, total ankle replacement is considered in a second stage.

[Anatomical and biomechanical aspects of total ankle replacement]. / Anatomische und biomechanische uberlegungen zur sprunggelenkprothetik.

The success of total ankle replacement highly depends on how successfully the physiological kinematics are maintained or reconstructed. Normal kinematics of the ankle joint can be replicated by designing an implant that is as close as possible to the normal bony anatomy, aligning the ankle and balancing the ligaments. Mimicking normal kinematics and kinetics of a healthy ankle joint will consequently decrease damaging joint contact stress forces and stress forces on the surrounding soft tissue, which may cause wear, implant failure, and pain. This article summarizes the anatomical and biomechanical basics that are required in total ankle replacement.