Update on stage IV acquired adult flatfoot disorder: when the deltoid ligament becomes dysfunctional

Deltoid ligament complex insufficiency is a fundamental pathologic component of stage IV AAFD. Failure of the deltoid ligament allows the talus to tilt into valgus within the ankle mortise. If left untreated, ankle joint biomechanics are altered and may lead to debilitating tibiotalar arthritis. All surgical treatments that address the valgus talar tilt seen with stage IV AAFD require accompanying procedures to properly realign the hindfoot. Stage IV AAFD can be subdivided into two groups. Patients with a flexible ankle deformity without advanced tibiotalar arthritis (stage IV-A) can be considered for a joint-sparing procedure. A variety of procedures have been described, but longterm follow-up studies have yet to determine which of these techniques is optimal. Patients with a rigid valgus ankle deformity or a flexible deformity accompanied by advanced tibiotalar arthritis (stage IV-B) should be considered for a joint-sacrificing procedure. To date, the most reliable results for stage IV-B AAFD have been reported with either tibiotalocalcaneal or pan-talar arthrodesis.     

Supramalleolar osteotomies for degenerative joint disease of the ankle joint: indication, technique and results

Patients with varus or valgus hindfoot deformities usually present with asymmetric ankle osteoarthritis. In-vitro biomechanical studies have shown that varus or valgus hindfoot deformity may lead to altered load distribution in the tibiotalar joint which may result in medial (varus) or lateral (valgus) tibiotalar joint degeneration in the short or medium term. The treatment of asymmetric ankle osteoarthritis remains challenging, because more than half of the tibiotalar joint surface is usually preserved. Therefore, joint-sacrificing procedures like total ankle replacement or ankle arthrodesis may not be the most appropriate treatment options. The short- and midterm results following realignment surgery, are very promising with substantial pain relief and functional improvement observed post-operatively. In this review article we describe the indications, surgical techniques, and results from of realignment surgery of the ankle joint in the current literature.     

Medial-sided bony procedures: why, what, and how?

The adult acquired flat foot deformity is a common clinical entity; rupture or incompetence of the posterior tibial tendon is a frequent cause. The natural history is characterized by progressively worsening deformity and early recognition is important. Nonoperative treatment can alleviate symptoms and control progression in nearly all stages of the disease. Should this fail to control symptoms or prevent progression of deformity, operative intervention should be considered. In stage I disease, exploration and debridement, with or without FDL tendon transfer, is a viable option. In stage II disease, the PTT becomes elongated and the medial soft tissues become attenuated. Exploration and debridement of the PTT is performed, but frequently a FDL tendon transfer or side-to-side anastomosis is required. It has been shown that soft tissue procedures alone may fail to correct deformity and this can lead to deterioration of results over time. Combined procedures, including soft tissue reconstructions to restore PTT function and bony procedures to correct deformity, have become popular. When the PTT is intact and degeneration or elongation is minimal, as in stage I or early stage II disease, reconstruction of the medial column with advancement of an osteoperiosteal flap based on the PTT insertion, combined with selective arthrodeses of the medial column, may be considered. These procedures have been well described for the treatment of symptomatic flexible flat foot in children and adolescents but experience in adults is lacking. Although it may be theoretically possible to passively correct hindfoot valgus with these procedures, it seems prudent to limit the indications to patients who have early disease accompanied by an isolated midfoot sag. In more advanced stage II disease, correction of deformity with a tendon transfer combined with a medial displacement calcaneal osteotomy or a lateral column lengthening is currently recommended. This allows for correction of deformity while sparing the hindfoot joints, which may be particularly important in young or active patients. Short-term studies showed excellent results, but long-term results are lacking. In stage III disease, in which the deformity is fixed, arthrodesis is the procedure of choice. Isolated talonavicular arthrodesis has been shown to correct nearly all aspects of the deformity with long-lasting results. This procedure results in nearly complete lack of hindfoot motion and may predispose the patient to adjacent joint arthrosis. In a patient who has stage III disease with arthrosis confined to the talonavicular joint, isolated talonavicular arthrodesis may be considered. This clinical situation is rare, and, in most patients, a triple arthrodesis is probably preferred. If residual deformity is present after these procedures, it must be addressed. Residual medial column instability may be addressed by adding a selective arthrodesis of the naviculo-cuneiform or first metatarsocuneiform joint, whereas residual forefoot varus or supination may be addressed with selected midfoot fusions with or without a cuneiform osteotomy.     

Valgus deformities of the feet and characteristics of gait in patients who have rheumatoid arthritis

To investigate the cause of valgus deformity of the hindfoot in patients who have rheumatoid arthritis and to characterize the effects of the deformity on gait, two groups of patients were evaluated clinically, radiographically, and with gait analysis in the laboratory. Group 1 consisted of seven patients who had seropositive rheumatoid arthritis and normal alignment of the feet and Group 2, of ten patients who had rheumatoid arthritis and valgus deformity of the hindfoot. In Group 2, the disease was of longer duration and the feet were more painful than in Group 1. There was no evidence of muscular imbalance, equinus contracture, valgus deformity of the tibiotalar joint, or isolated deficiency of the tibialis posterior (such as weakness, tenosynovitis, or rupture of the tendon) that could have contributed to the development of the valgus deformity. In the patients who had valgus deformity, quantitated electromyography demonstrated that the intensity and duration of activity of the tibialis posterior was significantly increased, apparently in an effort to support the collapsing longitudinal arch of the foot. Gait studies revealed decreases in velocity, stride length, and single-limb-support time, as well as delayed heel-rise in both groups, but the decreases were more marked in the patients who had valgus deformity. The results of this study suggest that valgus deformity of the hindfoot in rheumatoid patients results from exaggerated pronation forces on the weakened and inflamed subtalar joint. These forces are caused by alterations in gait secondary to symmetrical muscular weakness and the effort of the patient to minimize pain in the feet. Radiographs also suggested an association between the valgus deformity of the feet and valgus deformity of the knees in patients who have rheumatoid arthritis.     

Lateral-sided bony procedures

Treatment of any hindfoot deformity should include correction of the deformity and preservation of complex hindfoot motion. This important motion is protective of adjacent, and more removed, joints in that it serves a shock-absorbing function and protects them from stresses. Lateral column lengthening combined with a medial soft-tissue procedure is the treatment of choice for stage II flat foot. Patients who have significant subluxation of the subtalar joint will also need a medial displacement calcaneal osteotomy to correct the hindfoot valgus. Only patients who have a rigid foot secondary to degenerative changes will require an arthrodesis to correct the deformity and provide pain relief. Unfortunately, although fusion works well to correct deformity, it accelerates future degenerative changes.     

Open posterior approach for tibiotalar arthrodesis

Traumatic injury to the ankle and hindfoot often results in tibiotalar or subtalar arthritis. The associated joint pain, stiffness, and deformity may be difficult to treat with conservative measures. For such problems, arthrodesis of the ankle or hindfoot joints is the mainstay of treatment. This article discusses the application of the posterior approach to complete a tibiotalar and tibiotalocalcaneal arthrodesis as well as its use for converting a failed total ankle arthroplasty to an arthrodesis.     

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.     

Radiographic Analysis and Clinical Efficacy of Hindfoot Arthrodesis With Versus Without Cotton Osteotomy in Stage III Adult Acquired Flatfoot Deformity

Forefoot varus develops as a result of longstanding adult-acquired flatfoot deformity (AAFD). This occurs with varying degrees of deformity and flexibility. Residual forefoot varus following hindfoot realignment in AAFD can lead to lateral column loading and a persistent pronatory moment in efforts to reestablish contact between the forefoot and the ground. The Cotton osteotomy may serve as a reasonable adjunct procedure to help avoid complications and poor outcomes associated with residual forefoot varus in patients undergoing hindfoot arthrodesis for stage III AAFD. The aim of this study was to compare the radiographic outcomes in patients undergoing isolated hindfoot arthrodesis to patients undergoing hindfoot arthrodesis with adjunctive cotton osteotomy. We retrospectively reviewed 47 patients matched based upon age, sex, and comorbidities who underwent hindfoot reconstruction for the treatment of stage III AAFD between 2015 and 2019. A retrospective radiographic review was performed on standard weightbearing radiographs including anterior-posterior and lateral views preoperatively, postoperatively at the initiation of full weightbearing, and at final follow-up. Statistical analysis utilizing paired t test to calculate p values where <.05 was statistically significant. At final follow-up, radiographic measurements showed statistically significant differences in CAA, calcaneal inclination, talo-calcaneal, and talar tilt (p value <.05). The Cotton osteotomy group showed a quicker return to presurgical activity level and a decreased incident of tibiotalar valgus. Our study suggests that the Cotton osteotomy can address residual forefoot varus and potentially prevent further progression of ankle valgus in AAFD when used in combination with hindfoot arthrodesis.     

The medial approach to triple arthrodesis. Indications and technique for management of rigid valgus deformities in high-risk patients

Between 1995 and 2002 the authors treated 17 patients who had a rigid hindfoot valgus deformity, and for whom a triple arthrodesis was planned, using a single medial incision. The indication for surgery was pain that was refractory to shoe wear, orthotic, and brace modifications. The severity of the hindfoot deformity itself was not a sufficient indication for this procedure. All 17 patients were examined a mean of 3.5 years following surgery (1-8 years). Subtalar and talonavicular arthrodesis was achieved in all patients and calcaneocuboid arthrodesis was achieved in 15 of 17 patients (2 asymptomatic pseudoarthrosis). The medial approach to triple arthrodesis is a reliable procedure, and can be used with a predictable outcome in patients who are at risk for wound healing complications for correction of hindfoot valgus deformity.     

Lesser toe deformities

Lesser toe deformities are caused by alterations in normal anatomy that create an imbalance between the intrinsic and extrinsic muscles. Causes include improper shoe wear, trauma, genetics, inflammatory arthritis, and neuromuscular and metabolic diseases. Typical deformities include mallet toe, hammer toe, claw toe, curly toe, and crossover toe. Abnormalities associated with the metatarsophalangeal (MTP) joints include hallux valgus of the first MTP joint and instability of the lesser MTP joints, especially the second toe. Midfoot and hindfoot deformities (eg, cavus foot, varus hindfoot, valgus hindfoot with forefoot pronation) may be present, as well. Nonsurgical management focuses on relieving pressure and correcting deformity with various appliances. Surgical management is reserved for patients who fail nonsurgical treatment. Options include soft-tissue correction (eg, tendon transfer) as well as bony procedures (eg, joint resection, fusion, metatarsal shortening), or a combination of techniques.     

Fibular-Achilles tenodesis for paralytic ankle valgus

Children with myelomeningocele often develop progressive valgus deformity of the ankle that may be concomitant with, or mistaken for, paralytic hindfoot valgus. The same deformity is encountered in children who sustain lower motor neuron deficits. It is imperative to obtain an anteroposterior weight-bearing radiograph of the ankles to differentiate and document the degree of ankle valgus. To address the ankle deformity, we employed the fibular-Achilles tenodesis described by Westin. We are reporting our experience with 18 patients (32 ankles) who underwent this procedure. We noted improvement in relative fibular length and reduced talar tilt in 26 ankles (81.2%). In addition, there was some improvement in the orientation of the hindfoot; rotational deformity was unaffected.     

Arthrodesis of the hindfoot for valgus deformity. An entirely medial approach

Correction of valgus deformity of the hindfoot using a medial approach for a triple fusion has only recently been described for patients with tight lateral soft tissues which would be compromised using the traditional lateral approach. We present a series of eight patients with fixed valgus deformity of the hindfoot who had correction by hindfoot fusion using this approach. In addition, we further extended the indications to allow concomitant ankle fusion. The medial approach allowed us to excise medial ulcers caused by the prominent medial bony structures, giving simultaneous correction of the deformity and successful internal fixation. We had no problems with primary wound healing and experienced no subsequent infection or wound breakdown. From a mean fixed valgus deformity of 58.8 degrees (45 degrees to 66 degrees) pre-operatively, we achieved a mean post-operative valgus angulation of 13.6 degrees (7 degrees to 23 degrees). All the feet were subsequently accommodated in shoes. The mean time to arthrodesis was 5.25 months (3 to 9). We therefore recommend the medial approach for the correction of severe fixed valgus hindfoot deformities.     

Repair of the Deltoid Ligament Using Posterior Tibial Tendon Autograft:A Novel Technique

Posterior tibial tendon dysfunction (PTTD) is a progressive disorder secondary to advanced degeneration of the posterior tibial tendon, leading to the abduction of the forefoot, valgus rotation of the hindfoot, and collapse of the medial longitudinal arch. Eventually, the disease becomes so advanced that it begins to affect the deltoid ligament over time. This attenuation and eventual tear of the deltoid ligament leads to valgus deformity of the ankle. Surgical correction of PTTD is performed to protect the ankle joint at all costs. Generally, this is performed using osteotomies of the calcaneus and repair or augmentation of the deltoid ligament. Unfortunately, there has been no universal procedure adapted by foot and ankle surgeons for repair or augmentation of the deltoid ligament. Articles have discussed the use of suture and suture anchors, suture tape, nonanatomic allograft repair, nonanatomic autograft repair with plantaris, peroneal and extensor halluces longus tendons to repair and augment the deltoid ligament. There is very little literature, however, in regard to using the posterior tibial tendon to augment the deltoid ligament in accordance with hindfoot fusion for end-stage PTTD deformity. In general, the posterior tibial tendon in triple and medial double arthrodesis is generally removed because it is thought to be a pain generator. This article presents a case study and novel technique using the posterior tibial tendon to augment and repair the laxity of the deltoid ligament in an advanced flatfoot deformity.     

Positive hindfoot valgus and osteoarthritis of the first metatarsophalangeal joint

BACKGROUND: The aim of this retrospective cohort study was to evaluate the association between increased hindfoot valgus and the subsequent development of osteoarthritis of the first metatarsophalangeal (MTP) joint. Specifically, our hypothesis was that among individuals free from first MTP joint osteoarthritis, those who have positive hindfoot valgus are more likely to develop first MTP joint osteoarthritis than are those individuals with normal hindfoot alignment. METHODS: Our sample consisted of 1592 men and women, 40 years of age or older, participating in the Clearwater Osteoarthritis Study (1988 to 2001). Biennial physical examinations, including serial radiographs, were conducted. The Kellgren and Lawrence ordinal scale was used to determine radiographic evidence (grades 2+) of the study outcomes and incidence of first MTP joint osteoarthritis. Standing hindfoot valgus was assessed visually by a registered nurse, with a hindfoot valgus measurement of more than 5 degrees classified as a positive hindfoot valgus. RESULTS: Individuals with hindfoot valgus were 23% more likely to subsequently develop first MTP joint osteoarthritis than were those without hindfoot malalignment (risk ratio = 1.23; p-value < 0.006). This risk estimate reflects the potential influence of age, gender, and body mass index. CONCLUSIONS: Our data suggest that hindfoot valgus may increase the risk of developing foot osteoarthritis. The association of hindfoot valgus with first MTP joint osteoarthritis in this epidemiological assessment is supportive of the mechanical theory for the development of osteoarthritis. The authors speculate that future, related studies may determine that osteoarthritis prevention strategies can be broadened to include individuals with positive hindfoot valgus.     

Osteotomies of the distal tibia and hindfoot for ankle realignment

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.     

Posterior tibial tendon insufficiency. Isolated fusion of the talonavicular joint

In selected patients, fusion of the talonavicular joint can be an effective treatment of adult flatfoot deformity. Restriction of motion and altered hindfoot mechanics, however, are a consequence of talonavicular fusion and can lead to accelerated arthrosis of adjacent joints. In patients with severe long-standing deformity, medial displacement calcaneal osteotomy may be a necessary adjunct to talonavicular fusion for adequate correction of heel valgus.     

The treatment of rheumatoid foot deformities

Rheumatoid hindfoot deformity presents with hindfoot eversion, flattening of the longitudinal arch and abduction of the forefoot. Splayfoot, as the typical rheumatoid forefoot deformity, is mostly associated with various toe malformations, i.e. hallux valgus,hammer toe and claw toe,which may either be attributed to hindfoot malalignment or develop as a separate entity. The algorithm of treatment, comprising clinical assessment of both lower limbs, includes both orthotic shoe devices and surgical treatment. In rheumatoid flatfoot, arthrodesis of the hindfoot with lengthening of the lateral column and reorientation of joint congruency represent the gold standard of treatment. Despite this principle, the ankle joint should be kept mobile to facilitate standing and walking. Therefore, total ankle prosthesis is thought to be superior. Methods involving the preservation of the lesser metatarsophalangeal joints may be of benefit in providing sufficient ground contact with the toes. Nevertheless, resection arthroplasties are frequently required in cases of arthritic joint destruction. Arthrodesis of the first metatarsophalangeal joint may provide an adequate push-off for the big toe which can not be expected from resectional arthroplasties.     

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.     

Grice subtalar arthrodesis followed to skeletal maturity

A retrospective review of 45 patients (62 feet) who had undergone a Grice subtalar arthrodesis and who had reached skeletal maturity was undertaken. Preoperative deformities were due to flaccid and spastic paralysis, as well as congenital abnormalities. There were failures in 32% and poor results in 61%. Unrecognized ankle valgus, overcorrection of the hindfoot into varus, uncorrected calcaneus deformity, and anterior graft orientation largely contributed to the poor results. Weight-bearing radiographs of the feet and ankles are necessary to distinguish ankle valgus from hindfoot valgus. A subtalar arthrodesis cannot be used to compensate for ankle valgus, nor can it be used to correct the calcaneus component of a deformity without appropriate muscle-balancing procedures or osteotomies.     

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.