Evans Osteotomy Research Articles

Combined Medial Displacement Calcaneal Osteotomy and Hintermann Osteotomy Fixed With a Single Antegrade Screw: How Do We Do It?

Progressive collapsing foot deformity stage 1AB is often managed surgically with lateral column lengthening and medial displacement calcaneal osteotomy (MDCO), among other procedures. The Hintermann osteotomy is an option for lateral column lengthening with the theoretical advantage of decreased risk of subtalar and calcaneocuboid joint degeneration relative to the Evans osteotomy. It can be easily performed in conjunction with an MDCO to amplify the mechanical effects of each osteotomy. This paper serves as a technique guide for the Hintermann osteotomy combined with the MDCO and fixed with a single antegrade screw. Level of Evidence: Diagnostic level 5. See Instructions for Authors for a complete description of levels of evidence.

Biomechanical effects of Evans versus Hintermann osteotomy for treating adult acquired flatfoot deformity: a patient-specific finite element investigation.

Evans and Hintermann lateral column lengthening (LCL) procedures are both widely used to correct adult acquired flatfoot deformity (AAFD), and have both shown good clinical results. The aim of this study was to compare these two procedures in terms of corrective ability and biomechanics influence on the Chopart and subtalar joints through finite element (FE) analysis. Twelve patient-specific FE models were established and validated. The Hintermann osteotomy was performed between the medial and posterior facets of the subtalar joint; while, the Evans osteotomy was performed on the anterior neck of the calcaneus around 10mm from the calcaneocuboid joint surface. In each procedure, a triangular wedge of varying size was inserted at the lateral edge. The two procedures were then compared based on the measured strains of superomedial calcaneonavicular ligaments and planter facia, the talus-first metatarsal angle, and the contact characteristics of talonavicular, calcaneocuboid and subtalar joints. The Hintermann procedure achieved a greater correction of the talus-first metatarsal angle than Evans when using grafts of the same size, indicating that Hintermann had stronger corrective ability. However, its distributions of von-Mises stress in the subtalar, talonavicular and calcaneocuboid joints were lesshomogeneous than those of Evans. In addition, the strains of superomedial calcaneonavicular ligaments and planter facia of Hintermann were also greater than those of Evans, but both generally within the safe range (less than 6%). This FE analysis study indicates that both Evans and Hintermann procedures have good corrective ability for AAFD. Compared to Evans, Hintermann procedure can provide a stronger corrective effect while causing greater disturbance to the biomechanics of Chopart joints, which may be an important mechanismof arthritis. Nevertheless, it yields a better protection to the subtalar joint than Evans osteotomy. Both Evans and Hintermann LCL surgeries have a considerable impact on adjacent joints and ligament tissues. Such effects alongside the overcorrection problem should be cautiously considered when choosing the specific surgical method. Level III, case-control study.

An Emphasis on the Role of Peroneus Brevis to Peroneus Longus Transfer in Progressive Collapsing Flatfoot Deformity

The role of the peroneal tendons in progressive collapsing flatfoot deformity (PCFD), also traditionally known as posterior tibial tendon dysfunction, is likely overlooked and almost certainly understudied. We explored the impact of peroneus brevis (PB) to peroneus longus (PL) transfer in the adult population with flexible PCFD deformities class A1 (flexible hindfoot valgus), B1 (flexible midfoot abduction), and C1 (flexible forefoot varus) as an augmentative measure combined with various bony procedures with proper assessment functionally, clinically, and radiologically. PB to PL tendon transfer poses a simple procedure dealing with muscle imbalance between the medial and lateral columns of the foot. It deals with the new understanding of the PCFD complex as a three-dimensional deformity. It works mainly on the axial plane to limit midfoot abduction and strongly augments the PL acting on the sagittal plane to address the forefoot varus. Finally, to a lesser extent, it deals with the coronal plane of hindfoot valgus, eliminating the primary evertor of the foot (PB) while simultaneously strengthening the PL, which contributes to the medial longitudinal and transverse arches of the foot, therefore decreasing the possibility of lateral column overload commonly caused by the Evans osteotomy through reducing pressure across the calcaneocuboid joint. This procedure is preferably indicated for flexible PCFD deformities class (A1, B1, and C1), yet is contraindicated in neuromuscular deformities with peroneal nerve palsy. Level of Evidence: Level IV.

The Mini Bone Extra-articular Reconstruction System for Progressive Collapsing Foot Deformity—Surgical Technique With Cadaveric Quantification of Surrounding Anatomy

We present a novel surgical technique, the mini Bone Extra-articular Reconstruction (BEAR) system, that involves minimally invasive all BEAR systems. The surgical technique was used to perform the medial displacement calcaneal osteotomy, Evans osteotomy, and Cotton osteotomy on 9 cadaveric feet under fluoroscopic guidance. We also present a case series of patients who have undergone the procedure. We first carefully dissected the sural nerve, superficial peroneal nerve, and its branches from each cadaveric foot and evaluated injuries following the mini-BEAR osteotomy cuts. We then measured and recorded the distance between the osteotomy cuts and these anatomic structures. We believe that this technique can potentially replace the multiple long surgical incisions with minimal ones. Level of Evidence: Level IV.

Nonunion Rate of Evans Osteotomy Without Fixation Pediatric Flatfoot

Category: Hindfoot; Other Introduction/Purpose: The Evans osteotomy is a calcaneal lateral column lengthening procedure commonly used to correct flatfoot deformities. Currently, there is no consensus on whether fixation is needed when performing this osteotomy. Also, large sized grafts have been found to lead to degeneration of the calcaneocuboid joint. The aim of this study was to determine the nonunion rate of an unfixed Evans osteotomy with use of an allograft wedge performed in patients undergoing flexible flatfoot reconstruction and if addition of a medial calcaneal slide osteotomy will help limit graft size. Methods: We retrospectively reviewed 39 pediatric patients with idiopathic symptomatic flatfoot deformity who underwent 46 unfixed Evans osteotomies with allogenic bone graft for flatfoot reconstruction between March 2013 and September 2017, with a mean follow-up of 49 (range 9.9- 243.9) weeks. Hospital record, preoperative, follow-up radiographs and complications were reviewed. Results: Of the 46 feet, 42(91.3%) underwent an associated medial displacement calcaneal osteotomy. Mean graft wedge size was 7.2mm(SD 1.6). Mean time to union was 10.3weeks (range, 6.7-13.9)(Table 1). There were no nonunions. There was significant improvement in all radiographic parameters at final follow-up (Table 2). Postoperative calcaneocuboid subluxation occurred in 70% of feet, with no correlation with wedge size(r=0.01,p=0.53). Magnitude of calcaneocuboid subluxation was small and only significant at 6-months (p=0.02), with regression to no significance by 1-year(p=0.3). Mean change in calcaneocuboid subluxation at final follow-up was 1.07mm(SD 2.18), with postoperative subluxation diminishing over time(Table 3). No correlation was observed between wedge size and change in lateral column length (r=0.01,p=0.45). One patient had persistent sinus tarsi pain requiring arthroscopic debridement of fibrosis and graft prominence. Conclusion: An unfixed Evans osteotomy for symptomatic pediatric flatfoot deformity resulted in a significant improvement in the radiographic alignment and achieved 100% union rate with minimal calcaneocuboid subluxation at final follow-up. Performing adjunctive procedures allowed the Evans procedure to be routinely limited to less than 10 mm of lengthening. Mean graft size in our cohort was smaller than that reported by other studies. While calcaneocuboid subluxation was detectable in 70% of feet, it was small in magnitude and diminished with longer postoperative follow-up.

Biomechanical Study of Porous Osteotomy Block in Evans Osteotomy for Flat Foot Correction Based on Finite Element Method

ased on the finite element method, the effect of porous osteotomy block on the biomechanics of surrounding joints in the treatment of flat foot by Evans osteotomy is studied. The finite element method is used to simulate the osteotomy block for Evans osteotomy to correct flatfoot. The effect of Evans osteotomy on the foot force line is analyzed from the biomechanical point of view. The osteotomy blocks were divided into solid osteotomy blocks and porous osteotomy blocks, and normal foot and flat foot were used as control groups. The results show that Evans osteotomy can effectively improve the force line of the foot to correct the flat foot. Compared with the solid osteotomy block, the porous osteotomy block can also play a corrective effect and reduce the stress shielding effect when used for Evans osteotomy to correct the flat foot.

Longterm outcome after Evans osteotomy in adolescence: A case study

Identifying decompensation of idiopathic flexible flatfoot can be difficult due to varying levels of expression and the complexity of the condition, making patient selection for surgical treatment a challenge. This case report presents the long-term follow- up of an Evans operation performed due to painful flatfoot in adolescence, and discusses the probable mechanism behind the loss of correction.

Opening Cuboid Wedge Osteotomy (Zoom Osteotomy) for Triplanar Correction of Flexible Pes Planovalgus Deformities

Surgical correction of flexible pes planovalgus often involves reestablishing the length of the lateral column. This is a review of a cohort of patients who underwent an opening cuboid osteotomy with interpositional graft for triplanar correction of flexible pes planovalgus. The medical records of 35 patients involving 51 feet were reviewed. All patients were treated with an opening wedge osteotomy of the cuboid in combination with adjunctive procedures as needed for correction of the pes planovalgus deformity. Radiographs were obtained before and a minimum of 12 months after surgery. Preoperative and postoperative cuboid abduction and Meary's (lateral talometatarsal) angles were measured using the radiographs, and adjunctive procedures and complications were recorded. Mean follow-up was 46 (range, 12-85) months. The mean cuboid abduction angle improved from 20.3° (range, 8°-31°) to 6.6° (range, 0°-15°), and the mean Meary's angle improved from 10.5° (range, 0°-25°) to 2° (range, -3° to 15°). All patients also underwent adjunctive procedures at the time of cuboid osteotomy. In the 51 feet treated, there were 3 (6%) complications, including wound dehiscence, neuritis, and deep vein thrombosis. There were no recurrences. Triplanar correction of flexible pes planovalgus can be performed safely and successfully with an opening cuboid osteotomy as an alternative to the Evans Osteotomy.

A Modified Extra-articular Lateral Column Lengthening Procedure for Adult Acquired Flatfoot Deformity.

Lateral column lengthening (LCL), originally described by Evans, is an established procedure to correct stage II adult acquired flatfoot deformity (AAFD). However, the relative position between the facets is violated, and other problems may include nonunion, malunion, and calcaneocuboid (CC) joint subluxation. Herein, we report a modified extra-articular technique of LCL with hockey-stick osteotomy, which preserves the subtalar joint as a whole, increases bony apposition to enhance healing ability, and preserves the insertion of the calcaneofibular ligament to stabilize the posterior fragment to promote adduction of the forefoot. We retrospectively recruited 24 patients (26 feet) with stage II AAFD who underwent extra-articular LCL. The mean age was 55.7 ± 15.7 years, and the mean follow-up period was 33.4 ± 12.1 months. Associated procedures of spring ligament repair/reconstruction and posterior tibial tendon plication or flexor digitorum longus transfer were routinely performed and may also include a Cotton osteotomy, heel cord lengthening, or hallux valgus correction. Clinical and radiographic outcomes at the final follow-up were compared with the preoperative assessments. All patients achieved calcaneus union within 3 months of operation. The VAS pain score improved from 5.3 ± 0.75 preoperatively to 1.2 ± 0.79 at the final follow-up (P < .001), and the AOFAS Ankle-Hindfoot Scale from 63.5 ± 8.5 to 85.8 ± 4.8 points (P < .001). The radiographic measurements significantly improved in terms of the preoperative vs final angles of 8.9 ± 5.3 vs 15.2 ± 3.6 degrees for calcaneal pitch (P < .001), 20.5 ± 9.2 vs 4.9 ± 4.8 degrees for Meary angle (P < .001), 46.5 ± 5.2 vs 41.9 ± 3.2 degrees for lateral talocalcaneal angle (P < .001), 23.9 ± 8.5 vs 3.9 ± 3.1 degrees for talonavicular coverage angle (P < .001), and 18.2 ± 9.2 vs 7.3 ± 5.0 degrees for talus-first metatarsal angle (P = .002). The CC joint subluxation percentage was 7.0% ± 5.4% preoperatively compared with 8.5% ± 2.4% at the final follow-up (P = .101). No case showed progression of CC joint arthritis or CC joint subluxation (>15% CC joint subluxation percentage). One case showed transient sural nerve territory paresthesia, and 1 had pin tract infection. Three cases had lateral foot pain, which could be relieved by custom insoles. Modified extra-articular LCL as part of AAFD correction is a feasible alternative technique without subtalar joint invasion and may be associated with less CC joint subluxation compared with the Evans osteotomy. Level IV, retrospective case series.

Biomechanical Effects of Graft Shape for the Evans Lateral Column Lengthening Procedure: A Patient-Specific Finite Element Investigation.

The Evans calcaneal lengthening osteotomy procedure is widely used for correcting progressive collapsing foot deformity. However, it can result in overcorrection and degenerations of the calcaneocuboid joint. Different shapes of graft have been used in the Evans calcaneal osteotomy, but potential differences in their biomechanical effects is still unclear. The present study was designed to explore the biomechanical effects of graft shape and improve the Evans procedure to avoid or minimize detrimental effects. Twelve patient-specific finite element models were established and validated. A triangular or rectangular wedge of varying size was inserted at the lateral edge of calcaneus, and the degree of correction was quantified. The stress in spring ligaments and plantar fascia and the contact characteristics of the talonavicular and calcaneocuboid joints were calculated and compared accordingly. The rectangular graft provided a much higher degree of correction than triangular grafts did. However, the contact characteristics of the calcaneocuboid joint and talonavicular joint were abnormal, with clear sensitivity to increased graft size, and the modeled strain of the spring ligament increased. The finite element analysis predicts that the rectangular grafts provide a higher degree of correction, but risks overcorrection compared with triangular grafts. The triangular graft may have a lower degree of disturbance to the biomechanical behaviors of the midtarsal joint. The model shows that both the shape and size of an Evans osteotomy bone wedge can have effects on the contiguous joints and ligamentous structures. Those effects should be considered when selecting a bone wedge for an Evans calcaneal osteotomy. Level III, case-control study.

The Evans Calcaneal Osteotomy Using a Buried K-Wire Technique

Lateral column lengthening is a common procedure used to treat stage 2 of posterior tibial tendon dysfunction with acquired flat foot deformity. This was first described by Evans, who used a tricortical iliac crest bone graft in the anterior calcaneus for the correction of flat feet. The Evans osteotomy is a common reproducible osteotomy that offers triplanar correction. We describe a less common operative technique using a buried K-wire to fixate the osteotomy to prevent dorsal subluxation of the distal fragment. Level of Clinical Evidence: Diagnostic Level V. See Instructions for Authors for a complete description of levels of evidence.

Does the stabilization of the calcaneocuboid joint with Steinmann pin in Evans osteotomy affect its incidence of arthritis?

PurposeThis study aims to determine the effect of retaining a Steinmann pin in the calcaneocuboid joint on its rates of arthritis following Evans calcaneal osteotomy lengthening procedure. The study hypothesized that leaving the pin across the calcaneocuboid joint post-operatively would lead to higher rates of arthritis. MethodsThis is a retrospective review of patients under 18 years of age who underwent Evans osteotomy at our hospital from January 2015 to May 2020. The Patients were stratified into 2 groups: Group 1 (pin was left post-operatively across the joint and removed on follow-up) and Group 2 (pin was removed during surgery). Demographic data were recorded, including age, sex, and body mass index. Calcaneocuboid arthritis was determined by radiographic imaging at least one-year follow-up. Time to pin removal, size of the pin and graft, and subluxation were analyzed as possible risk factors for arthritis. Odds ratios (OR) and corresponding 95% confidence intervals (CI) were estimated. Results39 patients were included in the study: 24 patients had the pin removed post-operatively, and 15 had the pin removed intra-operatively. There were no significant differences between the 2 groups regarding body mass index, age, sex, or laterality. Calcaneocuboid arthritis rates were significantly higher in the Group 1 than Group 2 (12(50%) vs. 2(13.3%), respectively; p = 0.02). On multivariate regression, both age (OR, 1.305 [95%CI: 1.009−1.696]; p = 0.044) and leaving the pin in the joint postoperatively (OR, 7.661 [95%CI: 1.208−48.570]; p = 0.031) were found as risk factors for arthritis at follow-up. The mean time to pin removal, the size of the pin, and the size of the graft were not found to be significant predictors of arthritis (p > 0.05). ConclusionsThis study shows that leaving the Steinmann pin in the calcaneocuboid joint in children post-operatively is associated with an increased risk of developing early radiographic signs of calcaneocuboid joint arthritis.

Prospective Comparison of Subtalar Arthroereisis With Calcaneal Lengthening in the Management of Planovalgus Feet of Ambulatory Children With Spastic Cerebral Palsy?

Pes planovalgus (PPV) deformity is common among cerebral palsy (CP) patients. There is no true consensus about the best way of treating this common deformity, especially when surgical interference is required. Treatment options range from orthotics to complex surgical procedures. The purpose of this prospective study was to evaluate and compare the effectiveness of 2 different procedures in the correction of symptomatic flexible PPV in ambulatory CP patients. A total of 57 feet in 35 patients were divided into 2 groups: group 1, subtalar arthroereisis group, using the calcaneostop technique; group 2, lateral column lengthening group, using Evans osteotomy. Patients were assessed clinically by the clinical score proposed by Yoo et al and radiologically by measuring 7 weight-bearing angles, both preoperatively and 12 months postoperatively. Patients' (or parents') satisfaction and their tolerance to braces or shoes were assessed 12 months after surgery as secondary outcome parameters. There was a statistically significant improvement in both primary and secondary outcome parameters after both procedures in comparison to the preoperative parameters. No statistically significant differences were observed between the 2 groups regarding the outcomes of both procedures except for the greater power of arthroereisis in the correction of hindfoot valgus, which was statistically significant both clinically and radiographically. Both procedures are valid options for the surgical management of PPV in ambulatory children with spastic CP. The less-invasive nature and lower potential morbidity suggest that judicious use of arthroereisis is appropriate for some patients, especially in the context of single-event multilevel surgery. Level II: Prospective, comparative study.

Minimally Invasive Surgery for Correction of Adult Acquired Flat Foot Deformity: An Anatomic Study

Category:Midfoot/Forefoot; HindfootIntroduction/Purpose:Adult acquired flatfoot deformity (AAFD) is a complex and chronic debilitating condition characterized by a decrease in the medial arch height and, in advanced stages, a decrease in the talonavicular coverage angle as the forefoot drifts into pronation and abduction. Operative treatment of stage II deformity has changed significantly over the past few decades. Joint sparing procedures which aim to realign the hindfoot and augment the diseased tibialis posterior tendon with the flexor digitorum longus transfer are commonly performed. The introduction of minimally invasive surgery (MIS) has been associated with smaller incisions, less blood loss, and quicker recovery times. The purpose of this study was to qualitatively and quantitatively observe the tendinous and neurovascular structures at risk with MIS AAFD osteotomy procedures in cadaveric feet.Methods:MIS technique was used to perform medial displacement calcaneal, Evans, and Cotton osteotomies on nine cadaveric feet under fluoroscopic guidance. The sural nerve, superficial peroneal nerve and its branches, deep peroneal nerve, dorsalis pedis artery, saphenous vein, and peroneal and extensor hallucis longus tendons were carefully dissected from each cadaveric foot and evaluated for injuries following the MIS osteotomy cuts. The distance from the osteotomy cuts and these anatomic structures were measured and recorded.Results:On average, the sural nerve was 8.4 mm and 9 mm from the calcaneal and Evans osteotomy sites, respectively. The intermediate dorsal cutaneous nerve was on average 68.3 mm and 41.1 mm from the calcaneal and Evans osteotomy sites, respectively. The peroneal tendons were on average 16.7 mm and 0 mm from the calcaneal and Evans osteotomy sites, respectively. The extensor hallucis was an average of 1 mm from the Cotton osteotomy site. There was a partial tear injury to the peroneus brevis in four of the cadaveric specimens at the Evans osteotomy site without complete laceration. There was no injury to the sural nerve, superficial peroneal nerve and its branches, saphenous vein, deep peroneal nerve, dorsalis pedis artery, or extensor hallucis longus tendon.Conclusion:Tendinous and neurovascular structures are at risk with MIS AAFD osteotomy procedures. Care should be taken with soft tissue handling and blunt dissection to decrease iatrogenic injuries to these structures. Specifically, extra care and recognition of the peroneal tendons during the Evans osteotomy may prevent damage, as this structure was at greatest risk among the three osteotomy cuts. Future research studies evaluating this technique and the functional outcomes in patients in a clinical setting is warranted. Surgical technique studies are underway to implement smaller, yet appropriate bone grafts through mini incisions.

Radiographic Union of Evans Osteotomy Without Fixation

Category:Hindfoot; OtherIntroduction/Purpose:The Evans osteotomy is a lateral column lengthening procedure of the calcaneus that is commonly used to correct flexible flatfoot deformities. There is no consensus on whether fixation is needed to avoid nonunion and calcaneocuboid subluxation when performing this osteotomy. We assessed the nonunion rate and correlated extent of subluxation with graft size in an unfixed Evans osteotomy with an allograft wedge and no pinning of the calcaneocuboid joint at any point in the largest series of the procedure to date. Surgeries were performed in patients undergoing flexible flatfoot reconstruction.Methods:We retrospectively reviewed 120 consecutive patients who had undergone 145 unfixed Evans osteotomies by a single surgeon with allogenic bone graft for flatfoot reconstruction between January 2013 and October 2017, with a mean follow-up of 62.5 (range 9.4-266.7) weeks. The calcaneocuboid joint was not pinned during the procedure. Data were collected using clinical and radiographical examination during regular follow-up.Results:A total of 137 feet (94.5%) underwent a double calcaneal osteotomy with an associated medial displacement calcaneal osteotomy (MDCO). There was one nonunion (0.69%). The mean time to union was 10.8 (range, 6.7-17.9) weeks. There was significant improvement in all radiographic parameters postoperatively, including calcaneal pitch, talonavicular uncoverage, anteroposterior and lateral talo-first metatarsal angle, lateral column length, and naviculocuboid overlap (p<0.05). Minor postoperative calcaneocuboid joint subluxation (1.51 +- 2.3 mm) occurred in 72 of 118 feet (61.0%) and had no correlation with wedge size (r=0.06; 95% CI, -0.13, 0.24; p=0.6).Conclusion:An unfixed Evans osteotomy for symptomatic flatfoot deformity resulted in a significant improvement in the radiographic alignment of the foot with an exceptionally rare nonunion rate. Detectable calcaneocuboid subluxation was common but minimal in extent and was not correlated with wedge size in this series in which wedges were less than 12 mm in the maximum dimension. This report represents the largest series of the Evans procedure to date.

Union Rates and Deformity Correction Using the Hintermann Osteotomy in Type IIb Flatfoot Deformity

Category:Ankle; HindfootIntroduction/Purpose:Multiple Lateral column lengthening procedures have been described for the correction of the abduction component of stage II flatfoot deformity. The Hintermann osteotomy, although technically difficult, offers powerful lengthening of the lateral column with low risk of violating the articular cartilage of the subtalar joint as compared to the more widely performed Evans osteotomy. This study reports on the radiographic and clinical outcomes of the Hintermann osteotomy performed by a single surgeon.Methods:Patients who underwent reconstruction for stage II flatfoot deformity with a Hintermann lateral column lengthening were restrospectively identified. The talus-1st metatarsal angle, percent talus uncoverage, calcaneal pitch, lateral column length, CC joint subluxation, and distance from CC joint to the osteotomy were measured on pre and postop radiographs. Radiographic union was also assessed. The Kellgren-Lawrence scale was used to assess degenerative changes at the ST, CC, and TN joints.Charts were reviewed for comorbidities, clinical evidence of union, time to protected weightbearing, time to unrestricted weightbearing, signs of peroneal irritation, clinical signs of osteoarthritis progression, and complications. A paired students t test was used to identify differences in radiographic parameters.Results:Twenty-six patients (30 feet) met inclusion criteria. All osteotomies achieved union with only 1 (1/30) instance of delayed union. Average duration before clinical and radiographic union was 12.6 weeks (9-37). The AP Talus-1st metatarsal angle decreased on average of 12.3 degrees (STD 9.1) (p<0.0001). Percent talus uncoverage decreased on average 17.7 percent (STD 11.5%) (p<0.0001). Subluxation at the CC joint was found to increase on average 1.63mm (STD 1.99) (p<0.01). Only 3 patients (10%) had radiographic progression of osteoarthritis at either the CC or ST joint. No patients showed clinical signs of osteoarthritis and none went on to fusion. One patient had lateral hardware pain necessitating plate removal.Conclusion:The Hintermann osteotomy is a powerful tool for lateral column lengthening. In this series there was significant correction of the preoperative abduction deformity with no nonunions. Degenerative changes in the surrounding hindfoot joints were rare. One benefit of the Hintermann osteotomy is its ability to preserve the articular cartilage of the anterior and middle facets.

Procedure-Specific Hardware Removal After Evans Osteotomy.

The Evans osteotomy is a widely used procedure for the correction of adult and pediatric flexible flatfoot deformity. Locking plates are commonly used to stabilize the osteotomy and the allograft. However, there have been incidences of soft-tissue irritation caused by the hardware, requiring subsequent hardware removal. Therefore, we sought to review whether age, sex, or laterality of the procedure had any correlation with the rate of hardware removal. A retrospective review was performed of 47 consecutive patients who underwent an Evans calcaneal osteotomy between October 1, 2013, and October 1, 2016. Data were collected and analyzed based on age, sex, laterality, and the need for hardware removal. All of the 47 patients met the inclusion criteria. Seventy procedures were performed, and hardware removal was required in 16 patients and 21 feet (30%). The only statistically significant finding was that 11 females and only five males required either unilateral or bilateral hardware removal (P = .039). All 16 patients reported complete pain relief after hardware removal. Females are twice as likely as males to develop symptoms after locking plate application over an Evans osteotomy and may require hardware removal. Despite the low-profile nature of the locking plate to fixate the Evans osteotomy, the hardware can be a source of significant pain. Patients, especially females, should be cautioned about potential hardware-related pain and a possible follow-up procedure to remove the hardware.

Biomechanical Comparison of Hintermann and Evans Osteotomy for Lateral Column Lengthening

Category:Hindfoot, Midfoot/ForefootIntroduction/Purpose:Both Evans and Hintermann procedures are opening wedge calcaneal osteotomies used for lateral column lengthening in flatfoot reconstruction. Risks of lateral column lengthening include lateral forefoot overload and increased calcaneocuboid (CC) joint pressure. The Evans osteotomy is preformed closer to the CC joint increasing the theoretical risk of higher CC pressures. The Hintermann technique is a more posteriorly located osteotomy developed to avoid destabilization of the anterior calcaneal fragment and subsequent CC joint incongruency. The purpose of this study is to biomechanically compare the Evans and Hintermann osteotomies through analysis of CC joint pressures and forefoot plantar pressures after sequential lengthening of the lateral column.Methods:A flatfoot model with radiographic confirmation was created in 10 matched cadaveric specimens which were then randomly selected to undergo either the Evans or Hintermann osteotomy. Specimens were physiologically loaded and the peak pressure of the CC joint and forefoot plantar pressures were measured under the following conditions: (1) intact foot, (2) flatfoot, and (3) sequential lengthening of the lateral column from 6 mm to 14 mm, in 2 mm increments.Results:Lateral column lengthening lead to significantly increased pressure across the CC joint in both the Evans and Hintermann specimens. With increasing lateral column length, mean peak CC pressures ranged from 2.9–4.0 and 1.2–2.2 times intact CC pressure for the Evans and Hintermann group, respectively. Normalized mean and normalized peak CC pressures were significantly higher in the Evans osteotomy group compared to the Hintermann group at every level of distraction (see figure). The CC pressures under each testing condition were normalized with respect to the intact foot. Forefoot lateral plantar pressures were significantly increased in specimens corrected with Evans osteotomy at 10 mm and 12 mm of distraction compared to the intact foot.Conclusion:The Evans osteotomy lead to significantly higher CC pressures than the Hintermann osteotomy. This data suggests the Hintermann osteotomy for flatfoot reconstruction minimizes increase in CC joint pressures and could reduce the risk of subsequent CC osteoarthritis.

Anatomic Description of the Anterior Body Calcaneal Z-Osteotomy

Category: Ankle Introduction/Purpose: Flexible pes planovalgus is a common condition encountered by foot and ankle physicians. Many treatment options exist to correct this deformity. One such procedure is an Evans osteotomy of the anterior process of the calcaneus. Due to the complications seen with this type of osteotomy, there has been an attempt to reduce these complications and as a result, an anterior body calcaneal z-cut osteotomy was developed. This osteotomy is inherently more stable by design and fewer complications have been reported. In an attempt to further understand this osteotomy and to determine how much bony interface remained following this osteotomy, a cadaveric study was performed. Methods: A Z-cut osteotomy was performed on 10 cadaveric specimens with the distal arm exiting dorsal and 1 cm proximal to the calcaneocuboid joint, while the proximal arm exited plantarly. The central axis lengths of 15 mm and 20 mm were compared. An 8-mm wedge was placed in both the distal and proximal arms, and fixated with a staple. Digital calipers were used to measure the amount of bony apposition on the central arm between the wedges. Results: The average amount of bone apposition was 9.13 mm. When comparing the 20 mm to 15 mm central arm groups, the average bony apposition was 10.66 mm and 7.61 mm, respectively. Conclusion: Based on these results, the anterior body calcaneal Z-osteotomy provides enough bony apposition between both groups with an 8-mm wedge distraction. Further studies are warranted to evaluate the union rate between the classic lateral column lengthening osteotomy and the anterior body calcaneal Z-osteotomy.

Surgical Management of Stage 2 Adult and Pediatric Acquired Flatfoot Without Tendon Transfer or Arthrodesis: A Retrospective Study

Posterior tibial tendon dysfunction (PTTD) is a common pathology of the foot and ankle. Numerous techniques are available to reconstruct the flatfoot. Fusions and tendon transfers are popular methods; however, a wide range of complications have been associated with these procedures. The objective of the present study was to demonstrate the outcomes of reconstructive surgery for flatfoot correction without tendon transfer or arthrodesis. We performed a retrospective study of 43 patients and 56 feet who had undergone flatfoot reconstructive surgery from November 2011 to June 2016, with a mean follow-up period of 60 weeks (range 12 to 60 months). Each patient demonstrated a stage 2 flatfoot deformity classified using the Johnson and Strom classification. Depending on the patient's deformity, the procedures consisted of different variations of gastrocnemius recession, medial displacement calcaneal osteotomy, Evans osteotomy, and Cotton osteotomy. Six different preoperative and postoperative angles were radiographically measured on each foot studied. In all cases, the differences in the preoperative versus postoperative measurements were statistically significant (p < .003). We believe the foot and ankle surgeon can correct flatfoot deformity with the use of extraarticular procedures and create a plantigrade functional foot without fusion or tendon transfer.