Arthroscopic surgery
Arthroscopic surgery of the ankle joint has become standard procedures in orthopedics and traumatology in recent years and can be used for a variety of injuries and pathologies. Acute injuries such as joint fractures, syndesmosis ruptures, acute osteochondral fractures and ligament ruptures as well as chronic pathologies such as impingement, joint stiffness chronic ligament ruptures and osteochondral lesions can be treated arthroscopically or arthroscopically assisted nowadays.

Fracture treatment
Fractures of the ankle joint as well as the tarsus are common injuries after trauma in the context of sports or work accidents. The ankle joint bifurcation is most frequently affected. Here, all joint-forming parts can be affected (outer ankle, inner ankle, posterior edge of the tibia / so-called Volkmann triangle). Depending on the fracture as well as age and activity level, an individual decision is made as to whether conservative therapy with immobilization in a cast or Walker boot is possible or whether surgical treatment with arthroscopically assisted or open reduction and fixation with titanium screws or plates is required. In the not uncommon combination injuries with ligament rupture or syndesmosis rupture, these can be stably treated in the same session with sutures or anchor and suture pulley systems (tight-rope). In cases of increased force, the ankle joint roof may also be affected. These pilon fractures are often severely comminuted and must be finely reconstructed to counteract subsequent osteoarthritis development. For this purpose, it is not uncommon for bone grafting with the patient’s own or donor bone or bone substitute material to be necessary in order to provide good support for the joint surfaces. This may also require a chondrogenic matrix in cartilage defects to achieve regeneration. Fractures of the tarsal bones, such as the talus or calcaneus, very often involve one or more joint surfaces and therefore must be treated surgically, even with only minor displacements, to avoid late sequelae. For this purpose, often only titanium screws are used, but in some cases, such as complex calcaneal fractures, the bone must be reconstructed and stably fixed using titanium plates via a larger approach. It is important to achieve exercise stability to avoid post-traumatic joint stiffness. Fractures of the metatarsals and toes can often be treated conservatively. In some cases, however, when there is severe shortening, axial deviation or rotational malalignment, surgical treatment with screws and plates is necessary. A special case here is the Jones fracture in the base region of the 5th metatarsal. Due to critical blood circulation in the fracture area, healing is not usually guaranteed with conservative therapy and the development of pseudarthrosis is not uncommon. Therefore, this fracture should be treated with screw fixation.
After completion of bony healing, the implants can be removed in a second procedure if mechanical disruption occurs. However, a general recommendation for removal cannot be made nowadays; this is decided on an individual basis.

Ankle joint instability
Ankle ligament injuries are among the most common injuries, especially in sports. Almost everyone has fallen over with their ankle in the course of their life and suffered an ankle distortion. While simple injuries such as ligament strains often heal well without special therapy, higher-grade capsule-ligament injuries must be treated with appropriate ankle orthoses and targeted physical therapy to achieve the best possible functional outcome. In complex injuries involving the tibiofibular syndesmosis or multiple ligament ruptures in athletically active patients, surgical therapy with ankle arthroscopy and ligament suture or ligament reconstruction may also be required. However, despite adequate therapy, chronic ankle instability may develop in some cases (20-40%). Often, after initial trauma, patients report repeated episodes of toppling over with acute swelling, sometimes lasting only a short time, often accompanied by a feeling of instability with unsteadiness on uneven surfaces or load-dependent pain. It is also not uncommon to see limitation of motion due to either capsular scarring or osteophytes on the anterior tibia or talus. In symptomatic chronic ankle instability without improvement with consistent physical therapy, ligament reconstruction is indicated. This can be performed arthroscopically or arthroscopically-assisted. In modified anatomic ligament reconstruction according to Broström-Gould, the existing but lax ligament structures are first loosened, shortened, and fixed in correct tension to the bones (most commonly on the anterior lateral malleolus) with the aid of small suture anchors; in addition, the anterior portions of the medial ligamentous apparatus can be tensioned, thus addressing mild rotational instability. If insufficient residual structures are present, various ligamentoplasties can be performed both laterally and medially using different grafts or plastic ligaments (ligament bracing).

Impingement
An impingement syndrome of the ankle joint most commonly affects the anterior portion of the upper ankle joint, but can also occur in the posterior space of the upper ankle joint as well as in the lower ankle joint. A distinction is made between soft tissue and bony impingement with often a combination of both. In most cases, painful impingement occurs in the presence of capsular and ligamentous scarring following recurrent ankle injuries. The scars painfully jam between the bony structures in dorsiflexion. Impingement can also occur after recurrent microtrauma to the ankle, which leads to soft tissue hypertrophy and the formation of bony spurs. This symptomatology is often found in soccer players at the kicking leg and is also called “Soccer Ankle”. If impingement is clinically suspected, diagnostic infiltration with a local anesthetic can be performed in addition to radiologic imaging. On the one hand, pain relief confirms the diagnosis, and on the other hand, the surgical result after ankle arthroscopy with impingement resection can be simulated. Postoperatively, immobilization and weight-bearing restrictions are avoided and early exercise therapy is initiated in order to maintain the improved mobility and prevent new scarring.

Cartilage therapy / Osteochondral lesions
Ankle cartilage lesions can affect all joint surfaces. In the course of ankle joint distortions in recreational or sports accidents, the cartilage can be injured by crushing or shearing. It is not uncommon for the subchondral bone to be torn off as well (so-called osteochondral shear fracture / flake fracture). If the diagnosis is made early, the torn piece of cartilage can often be reduced to its bed arthroscopically or in an open technique and fixed in a stable manner with the aid of special absorbable nails or sutures so that it can heal again. In the case of fragments not suitable for refixation or chronic cartilage damage, various surgical options are available depending on the size and depth of the damage. For small and shallow defects, so-called bone marrow stimulating techniques can be used with good success. Here, after removal of the unstable cartilage parts in the base of the defect, the bone is superficially milled off and drilled with special instruments to release the bone marrow. The stem cells and growth factors contained in the bone marrow can then transform into new replacement cartilage in the defect. This effect can be enhanced by inserting a hyaluronic acid or collagen matrix into the defect to locally bind the leaked blood as well as the stem cells and growth factors and give the cells a space to develop (matrix augmented chondrogenesis, AMIC method). If there is also a bone defect, this can be filled with bone cylinders from the iliac crest during the operation in a gap-free and mechanically stable manner. However, for good success in surgical cartilage therapy, all accompanying pathologies must also be addressed. In particular, ligamentous instabilities and mechanical overload in the case of axial malalignment must be eliminated by appropriate procedures during the operation.

Correction of axial malpositions
The importance of the mechanical leg axis for the development of cartilage damage up to joint arthrosis has been known for a long time. Before the widening of joint prostheses, the correction of the mechanical leg axis was the most important surgical instrument for the treatment of osteoarthritis of the knee and ankle. Malalignment in the sense of increased valgus or varus in the ankle joint can be congenital or occur after fractures. The altered load on the inside or outside of the joint can damage the cartilage and promote the development of osteochondral lesions, which, if left untreated, will lead to ankle arthritis. In order to analyze the malalignment as well as the overload, whole-leg still images and, in some cases, slice images must be obtained (MRI and CT). This is followed by a detailed analysis and planning of the correction. First of all, the joint angles must be used to determine in which bone (femur, tibia) the deviation is present and whether an additive, a subtractive or a torsional correction is required. If the deformity is in the distal lower leg, there is an indication for a supramalleolar osteotomy. In complex cases, various corrections must also be combined with each other to restore correct weight-bearing. During the operation, corrections are then made with millimeter precision on the basis of the planning and the result is secured with a plate. Nowadays, modern plate fixators are available with which early full weight-bearing is usually possible after 4 weeks and which allow a quick return to everyday life. After bony healing of the osteotomy, good sports ability can often be achieved. All necessary accompanying procedures such as ligamentary reconstruction or treatment of (osteo-) chondral lesions can be performed arthroscopically in advance of the conversion osteotomy. The relief achieved can regenerate cartilage damage and protect reconstructed ligaments. In cases of malalignment in the hindfoot with increased valgus (bent flatfoot) or increased varus (hollow foot), calcaneal osteotomy can effectively correct the malalignment. Necessary tendon transfers to reinforce chronically insufficient tendons can be performed in the same session.

Tendon injuries and overuse, plantar fasciitis, heel spur.
For runners and ball athletes, it is not uncommon to experience pain in the Achilles tendon or plantar fascia, especially with changes in training volume (e.g. preparing for a running event like a marathon…). These two, closely related structures can cause severe pain, especially under stress but also at rest. However, the pain is strongest during the first steps in the morning after getting up. Often the affected feel a “tearing sensation”. In most cases, both pathologies are based on a shortening of the calf muscles, which can lead to a chronic overload of the Achilles tendon and/or plantar fascia. In some cases, the overload may also be exacerbated by chronic ankle instability. In the Achilles tendon, a distinction is made between the middle area and the attachment area. In the middle area, a pressure painful spindle-shaped thickening often occurs. The transition of a chronic (para-) tendinopathy to intratendinous partial ruptures is fluid and the stability of the tendon cannot be accurately assessed clinically or radiologically. In the attachment region, chronic tendinopathy can also lead to calcification of the tendon and formation of a dorsal calcaneal spur. The thickening of the tendon results in impingement, which can exacerbate the pain. Another cause of pain in the Achilles tendon insertion area can be intrinsic impingement due to an enlarged heel bone (Haglund bump). In this case, the tendon is impinged from the inside by the elevated heel bone. Chronic overloading of the plantar fascia due to shortening of the calf muscles causes irritation of the fibers at the base, which can also calcify and lead to a plantar heel spur. The basic therapy for these pathologies is always consistent physiotherapy with stretching exercises and extrinsic training of the calf muscles. A relatively new but very effective approach is Heavy Slow Resistance Training, which relies on heavy loading of the tendon to generate healing stimuli. In addition, fascia therapy is useful. In the Achilles tendon insertion area, focused shock wave therapy can also be used to activate regenerative processes. In chronic plantar fasciitis, ACP therapy has also proven useful as an adjunct. If conservative therapy fails, various surgical options are available for chronic tendinopathy of the Achilles tendon. For chronic (para-) tendinopathy in the mid-range, tendoscopy with decompression and synovectomy of the tendon can produce rapid improvement. In painful Haglund’s bump, endoscopic synovectomy and exostosis removal can decompress the tendon without affecting stability. Only in chronic attachment tendinopathy with dorsal heel spur, if conservative measures fail, open surgery with spur ablation as well as resection of the tendinopathic portions is required. Depending on the size of the spur, sometimes a larger portion of the tendon must be detached from the bone. In this case, the tendon must be refixed with bone anchors and a walker must be applied postoperatively for 6 weeks to promote healing of the tendon.
Rupture of the Achilles tendon is always a very traumatic experience and most commonly occurs between the ages of 30 and 50, more often in men than women. While some patients report a history of chronic pain suggestive of tendinopathy, many have an unremarkable history. While conservative therapy in Walker is only possible in a few cases with good contact of the rupture ends in plantar flexion, percutaneous suturing has become the gold standard in recent years for fresh ruptures without a history of tendinopathy. With this technique, the tendon ends can be approached in a controlled manner without opening the rupture. On the one hand, this significantly reduces the risk of wound healing disorders as well as infections, and on the other hand, the rupture hematoma is left with the growth factors so that the tendon can heal well under controlled tension. Obsolete ruptures and those with a history of tendinopathy continue to be treated openly using conventional techniques in order to remove tendinopathic tendon components and solid hematomas on the one hand. In both cases, follow-up treatment is performed in a Walker boot in the pointed foot position. As a rule, the leg can be loaded from the beginning.

Autologous blood therapy (PRP / ACP therapy)
In the case of incipient osteoarthritis, an increased destruction of chondrocytes (cartilage cells) occurs, often due to mechanical causes such as overloading in the case of axis defects or instability after ligament injuries or meniscus injuries. The dying cells lead to the release of several substances (mediators) that cause a more or less pronounced inflammatory reaction in the knee joint. This inflammation causes the synovium to produce more fluid, which leads to painful joint swelling and effusion. This persistent irritation sets in motion a spiral of pain under stress and swelling that is often difficult to break. In addition to classic decongestant measures such as cryotherapy, range-of-motion exercises, and anti-inflammatory and analgesic medications, the joint’s irritable state can be calmed by concentrated infiltrations of the patient’s own blood. Autologous conditioned plasma (ACP) therapy exploits the regenerative capabilities of blood plasma, as well as platelets and blood stem cells, to improve the joint environment and as well as relieve pain. During ACP therapy, 15 ml of blood is drawn from the patient’s arm vein in the doctor’s office using an innovative double syringe system. The blood, including the double syringe, is then processed in a special centrifuge. This concentrates its active ingredients – mainly platelets, growth factors, but also stem cells. This produces plasma enriched with active ingredients, which is then injected directly into the affected ankle. Each treatment lasts between 15 and 30 minutes. After the injection, the patient can immediately resume everyday activities. For the best possible results, three to five treatments are necessary, each one week apart. ACP therapy is thus an absolutely natural, very safe and well-tolerated type of pain therapy. It can help with osteoarthritis, tendon injuries and sports injuries to get fit again faster, reduce pain and significantly accelerate healing.

Osteoarthritis therapy with highly cross-linked hyaluronic acid and corticoids
In advanced osteoarthritis with deep cartilage damage or larger cartilage defects (grade 3-4), pain therapy as well as the treatment of chronic effusions can be challenging. In this case, injection therapy with the combination preparation CINGAL® has proven effective in many cases. It combines the immediate anti-inflammatory and analgesic effect of cortisone tramcinolone hexacetonide with the long-lasting efficacy of cross-linked hyaluronic acid with the highest active ingredient content – for proven rapid and long-lasting pain relief. In the doctor’s office, the injection is administered sterilely into the affected joint using a pre-filled syringe. In many cases, pain relief can be achieved over several months. Compared to other preparations with repeated (up to 5 weekly) injections, the risk of infection after injection is significantly lower.

Ankle joint endoprosthetics / arthrodesis
In the case of advanced painful arthrosis of the upper ankle joint, after exhausting all conservative therapeutic approaches and depending on the age and activity level of the patient, either a stiffening of the upper or lower ankle joint can be performed or a total endoprosthesis of the upper ankle joint can be implanted. Since both procedures compete with each other in older patients, an individual decision must be made together with the patient in each case. In younger patients with a high level of activity, an ankle arthrodesis is often preferable because it creates a load-bearing situation with good function after healing, does not require revision surgery at a later date, and thus meets the needs of more active patients.

Forefoot surgery
Of the many pathologies of the forefoot, hallux valgus, hallux rigidus, claw toes, hammertoes, metatarsalgia and tailor’s bunion are among the most common. Several conservative and surgical treatment approaches are available for each of these pathologies. These range from insole care and foot gymnastics and spiral dynamics to various surgical techniques involving osteotomies and tendon lengthening as well as tendon transfers. Depending on the degree of deformity, pain, radiologically visible arthritic changes as well as the activity level, an adapted concept from conservative to surgical therapy is created and thus each pathology is treated individually.