Calcaneal osteotomies for the treatment of adult-acquired flatfoot

Evans Calcaneal Osteotomy: Assessment of Multiplanar Correction

Flatfoot deformity consists of collapse of the medial arch, forefoot abduction, increased talonavicular uncoverage, and hindfoot valgus. Although numerous soft tissue and bony procedures have been proposed to correct each plane of deformity, there is a lack of objective data in the literature quantifying the amount of structural correction. The purpose of this study was to quantify the multiplanar deformity correction of the lateral column lengthening osteotomy (Evans) on hindfoot alignment through objective, reproducible, radiographic measurements. We retrospectively reviewed 45 Evans calcaneal osteotomy procedures in 24 female (53%) and 21 male (47%) feet performed on 40 patients (5 bilateral). The mean follow-up was 53 weeks (range, 32-116). The mean age at the time of surgery was 35 years (range, 11-73). Statistically significant improvement in radiographic alignment was found in the calcaneal inclination angle, tibial-calcaneal angle, tibial-calcaneal position, and the anteroposterior talo-first metatarsal angle (p < .0001 for all). Although a direct correlation between graft size and degree of angular correction was not observed, it should be noted the calcaneal graft size (mean, 11.8 mm) and the amount of hindfoot valgus correction (mean, 12.6°) appear to be clinically related. The results of this study support that the Evans calcaneal osteotomy corrects the hindfoot alignment in 3 planes as evidenced by our multiplanar radiographic measurements.

Lateral Column Lengthening Revisited: A Simple Intraoperative Approach to Ensure a True Extra-Articular Osteotomy

Lateral column lengthening is a common method for treatment of patients with symptomatic flat feet. Although variations of the technique have been described by many authors, there is a lack of agreement about the exact location of the osteotomy. Most authors tried to find the interval between the anterior and middle talocalcaneal facets but did not offer a reproducible method to achieve this purpose. The use of a plantarflexion anteroposterior view of the foot provides better visualization of the anatomic landmarks and helps to precisely perform the osteotomy anterior to the sustentaculum tali, with protection of the anterior and middle talocalcaneal facets.

Medial Displacement Calcaneal Osteotomy for Unilateral Adult Acquired Flatfoot: Effects of Minimally Invasive Surgery on Pain, Alignment, Functioning, and Quality of Life

We aimed to assess the effects of medial displacement calcaneal osteotomy (MDCO) through a minimal skin incision in terms of pain, function, and alignment in patients with unilateral adult acquired flatfoot. American Orthopedic Foot and Ankle Society (AOFAS) hindfoot scale and Numeric Pain Rating Scale (NPRS) were assessed as outcomes at the baseline (T0), at 6 months (T1), and at 1 year (T2) from surgery. We analyzed data of 20 patients (7 male and 13 female), mean aged 46.6 ± 5.34 years, showed significant differences after 6 months in terms of AOFAS total score (44.30 ± 7.39 vs 96.50 ± 4.89; p = .0001), AOFAS subitems (p < .001), and pain (NPRS: 7.95 ± 1.36 vs 1.05 ± 1.05; p = .0001). At 1 year after surgery (T2), all outcome measures still significantly differ from baseline (p < 01). Therefore, percutaneous MDCO through a minimal skin incision seemed to be safe and effective in the middle and long term in reducing pain and improving function and alignment in patients with unilateral adult acquired flatfoot.

[Degeneration of the posterior tibial tendon : Established and new concepts]

BACKGROUND

The most common cause of degeneration of the posterior tibial tendon is a congenital valgus deformity of the calcaneus. Other associated pathologies are forefoot supination, forefoot abduction and shortening of the gastrocnemius muscle.

DIAGNOSTICS

Loaded x‑rays of the foot in three planes as well as the hindfoot alignment view enable evaluation of the axis of the foot under static loading conditions. The posterior tibial tendon can be imaged with ultrasound and magnetic resonance imaging (MRI). The fatty degeneration of the posterior tibial muscle can be identified in MRI.

CONSERVATIVE THERAPY

Unloading of the posterior tibial tendon can be achieved by orthotics with medial support or braces.

SURGICAL THERAPY

The surgical therapy of the posterior tibial tendon alone has not been proven to be successful. The key element is the correction of the hindfoot valgus by medializing calcaneal osteotomy. Depending on the deformity, an additional lateral lengthening osteotomy of the calcaneus, as well as a dorsal open wedge osteotomy of the medial cuneiform bone (Cotton osteotomy) can additionally be indicated. The transposition of the tendon of the flexor digitorum longus muscle to the navicular bone is used to augment the posterior tibial tendon. Ruptures of the plantar calcaneonavicular ligament are sutured, in addition a sinus tarsi spacer can be implanted to protect medial soft tissues. A shortening of the gastrocnemius muscle is addressed by release of the aponeurosis. First results are published on use of biologically active substances, such as platelet rich plasma.

RESULTS

The correction of the hindfoot deformity as well as the subsequent treatment of the different components of the pathology lead to a significant improvement in foot function. Pre-existing degenerative alterations are limiting factors.

A mid-term follow-up of Koutsogiannis' osteotomy in adult-acquired flatfoot stage II and "early stage III"

INTRODUCTION

Koutsogiannis' osteotomy has been widely described to treat adult-acquired flatfoot. However, few articles describe its midterm follow-up. Our aim was to study clinical and radiological outcomes at least one year after surgery and to analyze whether a combined procedure on the medial soft tissue affected these outcomes.

METHODS

We performed a retrospective study of 30 feet of patients who underwent a Koutsogiannis' osteotomy due to adult-acquired flatfoot stage II and "early stage III": a stage III acquired flatfoot without any important structural deformities. The parameters studied were additional medial soft tissue procedures, clinical outcome through the American Orthopaedic Foot and Ankle Society (AOFAS) ankle and midfoot score as well as complications and radiological measurements.

RESULTS

Sixteen cases were "early stage III" and 14 stage II. Thirteen patients underwent an associated posterior tibial tendon (PTT) revision: in three cases an end-to-end suture was possible, seven cases needed a FDL transposition, and three underwent synovectomy. Statistically significant improvement was found in the AOFAS score although no significant changes were seen radiologically. No additional benefit was found with the revision of the posterior tibial tendon. As to clinical and radiological results, no differences were found between stage II and "early stage III". Five cases presented a mild dysesthesia but only one patient needed neurolysis.

CONCLUSIONS

We consider the Koutsogiannis' osteotomy to be a safe and effective procedure to reduce pain in patients with stage II and "early stage III" adult-acquired flatfoot.

Minimally Invasive Calcaneal Osteotomy: Does the Shannon Burr Endanger the Neurovascular Structures? A Cadaveric Study

Calcaneal osteotomies are used to correct hindfoot alignment. Traditional open procedures have been plagued with complications. Various minimally invasive techniques have been described but are laborious and time-consuming. A percutaneous technique using a side cutting "Shannon" burr offers a simple and reliable alternative; however, little evidence is available to address the safety concerns. The aim of the present study was to quantify the risk posed to the medial and lateral neurovascular structures using this technique. The study was performed at the anatomy department, University of Sussex, using 13 fresh-frozen, below-the-knee cadaveric specimens during a training session held by WG Healthcare UK, Ltd. (Letchworth, Herts). The participants were 11 consultant orthopedic surgeons, who were inexperienced in minimally invasive surgery, and 2 demonstrators. Each performed a chevron calcaneal osteotomy using a Shannon burr by way of a lateral percutaneous approach under fluoroscopic guidance. The authors subsequently dissected the specimens to identify the neurovascular structures, describe their anatomic relations and proximity to the burr, and note any damage incurred. No evidence was found of significant neurovascular injury. Two very small proximal branches of the sural nerve were transected, the nerve itself passing safely 9 to 21 mm anterosuperior to the entry point. The medial neurovascular bundle crossed the path of the osteotomy in 4 specimens but was protected by the medial head of the quadratus plantae muscle. In conclusion, the Shannon burr for calcaneal osteotomy has the potential to minimize the surgical morbidity and maximize surgical efficiency without compromising safety in all patients with normal anatomy of the quadratus plantae muscle.

Effectiveness of a locking plate in preserving midcalcaneal length and positional outcome after Evans calcaneal osteotomy: a retrospective pilot study

When using the Evans calcaneal osteotomy for repair of a calcaneovalgus deformity, lengthening of the lateral column of the foot is the method by which the procedure acts to correct the deformity. Therefore, maintaining the length is a priority. In our experience, substantial length is lost soon after surgery using the traditional nonfixated procedure. To test this hypothesis, a retrospective study was undertaken in which we compared the calcaneal length before and after the Evans procedures in 22 patients treated without fixation and 13 patients in whom the graft was fixated with a small locking plate to bridge the osteotomy and reduce the compressive forces on the graft. Within the first 10 days after surgery, the increase in calcaneal length from the preoperative length was 6.3 mm in the nonfixated group and 6.8 mm in the fixated group (p = .54 for the 0.5-mm difference). At 12 weeks after surgery, the mean amount of shortening from the value observed at 1 week was 2.45 (range 0 to 6) mm in the nonfixated group and 1.0 (range 0 to 3) mm in the internal fixation group (p = .48). Also, at 12 weeks, distal calcaneal migration or dorsal anterior calcaneal displacement of more than 3 mm occurred in 5 patients (23%) in the nonfixated group and 1 patient (8%) in the fixated group (p = .04). Our results suggest that locking plates do preserve the correction obtained with the Evans calcaneal osteotomy.

The underlying osseous deformity in plantar plate tears: a radiographic analysis

PURPOSE

Plantar plate tears can cause pain and deformity of the forefoot. The purpose of this study is to correlate common radiographic findings with observed intra-operative pathology in patients with plantar plate pathology.

METHODS

Bilateral weight-bearing radiographs were reviewed for 88 patients (106 feet) who underwent surgical repair of suspected plantar plate pathology. Parameters reviewed included the first intermetatarsal angle, the metatarsus adductus angle, the second and third metatarsophalangeal angles, splaying of the second and third toes, evaluation of the metatarsal parabola by 3 different methods, the first and second lateral declination angles, and the second lateral metatarsophalangeal angle.

RESULTS

Of 106 feet, 97 had intra-operative plantar plate tears. The radiographs of patients with plantar plate tears had an increased amount of digital splay on the anteroposterior radiograph compared to patients without pathology. For patients with unilateral plantar plate pathology, the metatarsal parabola of the symptomatic foot was compared with that of the asymptomatic foot. A significantly increased second metatarsal protrusion distance as measured by 2 different methods was noted in the symptomatic foot. Odds ratios revealed that patients with an intermetatarsal angle >12, medial deviation of the second toe, and splaying of the digits were more likely to be diagnosed with a plantar plate tear intra-operatively.

CONCLUSION

Although radiographs do not definitively diagnose plantar plate tears, understanding osseous forefoot architecture will aid with diagnosis in the absence of other osseous pathology. Furthermore, these data suggest that parabola should be corrected to maintain long-term correction of plantar plate pathology.

LEVEL OF EVIDENCE

Prognostic, Level II.

Double calcaneal osteotomy using single, dual-function screw fixation technique

Historically, a variety of fixation techniques for calcaneal osteotomies have been used. The prevention of postoperative sequelae, including delayed or nonunion of the osteotomy sites and minimization of soft tissue damage, is always a primary consideration for foot and ankle surgeons. The present report describes a fixation technique for a double calcaneal osteotomy that entails use of a single screw that functions as both a positional tool, as well as a compressive fixation device. This technique provides compressive and positional qualities and decreases the amount of soft tissue disruption to the surgical site.

Effects of surgical correction for the treatment of adult acquired flatfoot deformity: a computational investigation

Computational models of the foot/ankle complex were developed to predict the biomechanical consequences of surgical procedures that correct for stage II adult acquired flatfoot deformity. Cadaveric leg and foot bony anatomy was captured by CT imaging in neutral flexion and imported to the modeling software. Ligaments were approximated as tension only springs attached at insertion sites. Muscle contraction of the gastrocnemius/soleus complex was simulated through force vectors and desired external loads applied to the model. Ligament stiffnesses were modified to reflect stage II flatfoot damage, followed by integration of corrective osteotomies-medializing calcaneal osteotomy (MCO) and Evans and calcaneocuboid distraction arthrodesis (CCDA)--to treat flatfoot. Joint angles, tissue strains, calcaneocuboid contact force, and plantar loads were analyzed. The flatfoot simulation demonstrated clinical signs of disease evidenced by degradation of joint alignment. Repair states corrected these joint misalignments with MCO having greatest impact in the hindfoot, and Evans/CCDA having greatest effect in the mid- and forefoot. The lateral procedures unevenly strained plantar structures, while offloading the medial forefoot, and increased loading on the lateral forefoot, which was amplified by combining with MCO. The Evans procedure raised calcaneocuboid joint contact force to twice intact levels. Computational results are in agreement with clinical and experimental findings. The model demonstrated potential precursors to such complications as lateral tightness and arthritic development and may thus be useful as a predictor of surgical outcomes.