What is the role and limit of calcaneal osteotomy in the cavovarus foot?

Ankle Instability and Peroneal Disorders in Cavovarus Feet: Do I Need a Calcaneal Osteotomy?

In order to understand the relation among ankle instability, peroneal disorders, and cavovarus deformity, it is mandatory to clarify the different stages of those disorders and also to put them into relation to each other. Finally, we need to take the patients compliance and expectations into consideration to define the individually right way of treatment.

The Surgical Correction of Cavovarus Deformity in Charcot-Marie-Tooth Disease

Charcot-Marie-Tooth (CMT) disease is the most commonly inherited neuropathy. CMT disease is a motor-sensory neuropathy with multiple genotypes. By comparison, the phenotypic expression is more uniform, with two main presentations. Most patients who need surgical care have progressive cavovarus foot deformity, with muscle imbalance causing a nonplantigrade foot, soft-tissue contractures, and abnormal bone morphology. Surgical treatment can be life-changing for these patients, allowing them to walk potentially brace free with more endurance and less pain. Early realignment procedures may reduce progression of joint arthritis. A minority of patients have diffuse paralysis below the knee. These patients are best treated with ground-reaction ankle-foot orthoses. This review article is based on the senior author's extensive experience with CMT, along with the limited evidenced-based literature.

Treatment of Charcot-Marie-Tooth neuropathies

Charcot-Marie-Tooth (CMT) is a heterogeneous group of inherited neuropathies that affect the peripheral nerves and slowly cause progressive disability. Currently, there is no effective therapy. Patients' management is based on rehabilitation and occupational therapy, fatigue, and pain treatment with regular follow-up according to the severity of the disease. In the last three decades, much progress has been made to identify mutations involved in the different types of CMT, decipher the pathophysiology of the disease, and identify key genes and pathways that could be targeted to propose new therapeutic strategies. Genetic therapy is one of the fields of interest to silence genes such as PMP22 in CMT1A or to express GJB1 in CMT1X. Among the most promising molecules, inhibitors of the NRG-1 axis and modulators of UPR or the HDACs enzyme family could be used in different types of CMT.

Midterm Clinical and Radiographic Outcomes of the Calcaneal Z-Osteotomy for the Correction of Cavovarus Foot

Background

The Malerba calcaneal Z-osteotomy is an operative procedure to treat the hindfoot varus component of adult cavovarus deformity. Basic science studies support the corrective ability of this osteotomy. However, there have been no published midterm clinical and radiographic results. The purpose of this article is to describe the radiographic and clinical improvement in a series of patients treated with this osteotomy.

Methods

A retrospective chart review identified 14 feet in 12 patients from January 2013 to August 2018 who met minimal follow-up criteria. Preoperative visual analog scale (VAS) scores, Foot Function Index (FFI) scores, and American Orthopaedic Foot & Ankle Society (AOFAS) scores were compared with postoperative scores. Preoperative Meary angle, calcaneal pitch, and hindfoot alignment were also compared with postoperative measurements. Complications and radiographic union were recorded.

Results

At a mean of 80 months, VAS, FFI, and AOFAS scores improved from 7.86 to 1.64, 57.78% to 18.11%, and 39.57 to 80.71, respectively (all P < .001). At a mean of 15 months, Meary angle, calcaneal pitch, and hindfoot alignment improved from 11.14 to 6.64 degrees (P < .001), 30.93 to 27.43 degrees (P = .005), and 19.83 degrees varus to 8.50 degrees varus (P < .001). There was 1 nonunion and 1 postoperative sural nerve neuralgia, but both patients ultimately did well clinically. There were no instances of postoperative tarsal tunnel syndrome. All patients stated that they would have the procedure done again.

Conclusion

The calcaneal Z-osteotomy is an effective method to treat adult hindfoot cavovarus deformity. All patients had good clinical outcomes with minimal complications.

Level of Evidence

Level IV, case series.

Lateralizing Calcaneal Osteotomy and First Metatarsal Dorsiflexion Osteotomy for Cavovarus Foot and Peroneal Sheath Release with Peroneus Brevis Repair for Peroneal Tendinopathy in Chronic Ankle Instability and Sprain

A 47-year-old male presented with an eight-year history of pain in the posterior inferior part of the lateral malleolus, ankle instability, and repeated right-sided ankle sprains. He had pes cavus and hind-foot varus in his right foot, which is an unknown congenital entity or acquired with tenderness in the inferior peroneal retinaculum. There is no deformity in his left foot. The pain was elicited by the movement of the subtalar joint. Imaging revealed a high medial longitudinal arch, an enlarged peroneal tubercle, thinning of the peroneus brevis tendon, and hypertrophy of the peroneus longus tendon. We diagnosed peroneal tendinopathy with cavovarus foot in a chronic ankle sprain. The supination generated by pes cavus was thought to be aggravating the peroneal tendinopathy and causing the ankle sprains. Incision of the peroneal tendon sheath, repair of the peroneus brevis tendon, lateralizing calcaneal osteotomy, and first metatarsal dorsiflexion osteotomy were performed. At the one-year follow-up, Meary's angle was corrected to 0°, the calcaneal pitch was corrected to 20°, and the hindfoot varus was improved. He was pain-free and reported no further instability when walking. His Japanese Society of Surgery of the Foot ankle-hindfoot scale score improved from 59 preoperatively to a maximum of 100 and the Self-Administered Foot Evaluation Questionnaire gave an almost perfect score for non-sports-related items and a score of 83.3 for sports-related items. We believe that the addition of treatment of the pes cavus, which was the center of the pathology, as well as treatment of the peroneal tendon, resulted in a good outcome.

Effectiveness of calcaneal osteotomy in surgical treatment of foot conditions: A Prisma statement guidelines compliant systematic review

Calcaneal osteotomy is a commonly established method used to correct various foot malalignment surgery problems that produce varus and valgus hindfoot abnormality as well as Haglund's deformity, cavovarus foot reconstruction, flatfoot deformity, plantar fasciitis, posterior tibial tendon insufficiency and planovalgus foot. After decades, several procedures in orthopaedic foot surgery have been suggested for reducing the risk of wound and neurovascular complications. The goal of this Prisma statement guidelines compliant systematic review was to establish the effectiveness and safety of calcaneal osteotomy in foot surgery. We have performed a novel systematic review of the current published literature in order to evaluate the scientific evidence now available on this association, assigning predefined exclusion and inclusion criteria. Eight investigations were selected which had 191 cases. The adult flatfoot, tibialis posterior reconstruction and cavovarus foot deformity were treated with different procedures of calcaneal osteotomy techniques. The adequate level of effectiveness of calcaneal osteotomy is associated with the kind and location of the incision, with or without screw application, in each specific foot condition. There is a limited number of scientific investigations of the effectiveness and safety of the different kinds of calcaneal osteotomy in foot surgery, and there is the need to enhance outcome knowledge on this foot surgery technique.

Evaluation and Management of Cavus Foot in Adults: A Narrative Review

Objective: Cavus foot is a deformity defined by the abnormal elevation of the medial arch of the foot and is a common but challenging occurrence for foot and ankle surgeons. In this review, we mainly aim to provide a comprehensive evaluation of the treatment options available for cavus foot correction based on the current research and our experience and to highlight new technologies and future research directions. Methods: Searches on the PubMed and Scopus databases were conducted using the search terms cavus foot, CMT (Charcot–Marie–Tooth), tendon-transfer, osteotomy, and adult. The studies were screened according to the inclusion and exclusion criteria, and the correction of cavus foot was analyzed based on the current research and our own experience. At the same time, 3D models were used to simulate different surgical methods for cavus foot correction. Results: A total of 575 papers were identified and subsequently evaluated based on the title, abstract, and full text. A total of 84 articles were finally included in the review. The deformities involved in cavus foot are complex. Neuromuscular disorders are the main etiologies of cavus foot. Clinical evaluations including biomechanics, etiology, classification, pathophysiology and physical and radiological examinations should be conducted carefully in order to acquire a full understanding of cavus deformities. Soft-tissue release, tendon-transfer, and bony reconstruction are commonly used to correct cavus foot. Surgical plans need to be customized for different patients and usually involve a combination of multiple surgical procedures. A 3D simulation is helpful in that it allows us to gain a more intuitive understanding of various osteotomy methods. Conclusion: The treatment of cavus foot requires us to make personalized operation plans according to different patients based on the comprehensive evaluation of their deformities. A combination of soft-tissue and bony procedures is required. Bony procedures are indispensable for cavus correction. With the promotion of digital orthopedics around the world, we can use computer technology to design and implement cavus foot operations in the future.

Safe zone for minimally invasive calcaneal osteotomy: an MRI study

Hindfoot deformities are often surgically corrected with calcaneal osteotomy. These are increasingly performed via a minimally invasive approach. Identifying a neurovascular "safe zone" for this approach is important in reducing iatrogenic injury. We aimed to identify a safe zone for minimally invasive calcaneal osteotomy without neurovascular injury. Three individuals independently assessed 100 con- secutive magnetic resonance imaging ankle studies. The distance of the medial neurovascular bundle from the level of the centre of the Achilles tendon insertion was measured. The points measured were centralised in three planes (axial, sagittal and coronal). The three sets of observations were statistically analysed with confidence intervals and intraclass correlation coefficient was calculated. The mean distance measured by the three observers were 22.91 mm (range 18.2-28.5 mm); 22.81 mm (range 18.7-26.7 mm); and 23.41 mm (range 19.2- 28.4 mm); overall mean 23.0 mm. The mean inter- observer variation was 1.1 mm. 95% confidence interval for observer 1 ranges from 22.45-23.25 mm, observer 2 ranges from 22.52-23.1 mm and observer 3 ranges from 22.97-23.65 mm. Overall 95% confidence interval ranges from 22.8-23.2 mm. Intraclass correlation coefficient for inter-observer reliability is 0.7, indicating strong agreement between the observers. This radiological study suggests an anatomical "safe zone" for minimally invasive medial calcaneal osteotomy is at least 18 mm (mean: 23 mm) from the level of insertion of the Achilles tendon. Individual variation between patients must be taken in to consideration during preoperative planning.

Use of Calcaneal Osteotomies in the Correction of Inframalleolar Cavovarus Deformity

Cavovarus deformity is a complicated condition most commonly resulting from neurologic, posttraumatic, or iatrogenic pathologic conditions. Careful evaluation of the cavovarus patient is necessary in determining appropriate treatment course. Weight-bearing radiographs are necessary, and advances in computed tomographic technology can be beneficial in identifying level of involvement. In the case of operative treatment of inframalleolar deformity, assessment of the subtalar joint position and relation of calcaneocuboid joint can be of assistance. Multiple osteotomies have been described providing uniplanar, biplanar, and triplanar correction and in the appropriate setting can prove beneficial to the surgeon in treating hind-foot cavovarus deformity.

A Consensus Statement on the Surgical Treatment of Charcot-Marie-Tooth Disease

BACKGROUND

Charcot-Marie-Tooth (CMT) disease is a hereditary motor-sensory neuropathy that is often associated with a cavovarus foot deformity. Limited evidence exists for the orthopedic management of these patients. Our goal was to develop consensus guidelines based upon the clinical experiences and practices of an expert group of foot and ankle surgeons.

METHODS

Thirteen experienced, board-certified orthopedic foot and ankle surgeons and a neurologist specializing in CMT disease convened at a 1-day meeting. The group discussed clinical and surgical considerations based upon existing literature and individual experience. After extensive debate, conclusion statements were deemed "consensus" if 85% of the group were in agreement and "unanimous" if 100% were in support.

CONCLUSIONS

The group defined consensus terminology, agreed upon standardized templates for history and physical examination, and recommended a comprehensive approach to surgery. Early in the course of the disease, an orthopedic foot and ankle surgeon should be part of the care team. This consensus statement by a team of experienced orthopedic foot and ankle surgeons provides a comprehensive approach to the management of CMT cavovarus deformity.

LEVEL OF EVIDENCE

Level V, expert opinion.

Medial Soft-Tissue Release for Lateralising Calcaneal Osteotomy: A Cadaveric Study

BACKGROUND

Lateralising calcaneal osteotomy for pes cavus is generally regarded to be harder to shift than a medialising calcaneal osteotomy for pes planus. The aim of our study was to determine the structures which restrain a lateral shift.

METHODS

Lateralising calcaneal osteotomy was performed on four soft-embalmed cadavers via a standard lateral approach and the lateral calcaneal shift was measured before and after the release of flexor retinaculum. Further exploratory dissection around the osteotomy site revealed the abductor hallucis muscle to be the main restraint to the lateral shift of the calcaneus. Subsequently, lateralising calcaneal osteotomy was performed on another four cadavers and the abductor hallucis muscle fascia as well as the plantar fascia was released. The lateral shift was measured before and after the fascia release, and compared with the results achieved following the flexor retinaculum release in the first four cadavers.

RESULTS

Lateralising calcaneal osteotomy alone resulted in an average of 4.5-mm lateral shift in the first four cadaveric specimens. Releasing the flexor retinaculum led to a further 3-mm increase of lateral shift on average. In the next four cadaveric specimens, lateralising calcaneal osteotomy alone resulted in an average of 5.5-mm lateral shift. Release of abductor hallucis muscle fascia and the plantar fascia in these four specimens increased the lateral shift by an additional 7 mm on average. Hence, release of abductor hallucis muscle fascia resulted in an extra 4-mm shift on average compared with what is achieved with flexor retinaculum release.

CONCLUSIONS

Abductor hallucis muscle fascia was discovered to be one of the main structures limiting the lateral shift in lateralising calcaneal osteotomy. Release of fascia over this muscle as well as the plantar fascia should help in improving lateral shift. Further experimental and clinical research is necessary to confirm the findings of this pilot study.

Inframalleolar Varus Deformity: Role of Calcaneal Osteotomies

The cavo varus foot is a complex pathology due to skeletal deformity and neuro-muscular unbalance. The key concept for a successful treatment is to consider the whole foot and ankle complex from a bone and soft tissue perspective. Undercorrection is the main issue in cavo varus foot management, which may be attributed to intrinsic correction defects of the described calcaneal osteotomies or to a lack of understanding about the pathology and the subsequent algorithm of treatment. The authors disclose their daily algorithm of treatment, considering the foot and ankle complex and the role of calcaneal osteotomies in ankle inframalleolar deformities.

Comparison of Lateralizing Calcaneal Osteotomies for Varus Hindfoot Correction

BACKGROUND

There is limited consensus on the optimal operative technique for correcting heel varus in patients with Charcot-Marie-Tooth (CMT) disease. This comparative study evaluated the ability of 4 lateralizing calcaneal osteotomies, with and without Dwyer wedge resection and coronal rotation of the posterior tuberosity, to correct severe heel varus.

METHODS

The computed tomography (CT) scan of a teenage CMT patient with severe hindfoot varus was used to create 3-dimensional (3D)-printed models of the talus, calcaneus, and cuboid. A custom jig facilitated precise replication of the osteotomy cuts. Four different configurations were created: oblique osteotomy with lateralization, oblique osteotomy with lateralization and internal rotation of the posterior tuberosity, Dwyer wedge resection with lateralization, and Dwyer wedge resection with lateralization and internal rotation. CT scans were performed on each model before and after osteotomy. Statistical analysis was used to evaluate differences in several predefined radiographic parameters.

RESULTS

The sequential transformations generated increasing lateral translation of the weight-bearing calcaneus. Dwyer wedge osteotomy significantly improved lateralization (effect = 8.0 mm), valgus hindfoot angle (effect = 6.1 degrees), and coronal calcaneal tilt (effect = -17.6 degrees) compared with the oblique osteotomy. Internal rotation of the posterior tuberosity further improved lateralization (effect = 3.3 mm), valgus hindfoot angle (effect = 2.5 degrees), and coronal calcaneal tilt (effect = -11.7 degrees). Dwyer osteotomy models had on average 5-mm shorter posterior tuberosity lengths than the oblique osteotomies. The addition of rotation did not significantly affect length.

CONCLUSIONS

Significant lateralization of the posterior tuberosity was achieved in all transformations. The Dwyer wedge osteotomy improved hindfoot valgus angle, coronal calcaneal tilt, and lateralization of the weight-bearing surface compared with oblique osteotomy. Posterior tuberosity internal rotation further lateralized the plantar surface and normalized weight bearing. Lateralization, combined with Dwyer osteotomy and coronal plane internal rotation, achieved the greatest correction of varus heel.

CLINICAL RELEVANCE

This study compares multiple lateralizing calcaneal osteotomies and proposes a combined technique of lateralization, Dwyer wedge resection, and coronal plane rotation to address advanced cavovarus hindfoot deformities.

Use of 3D Prints to Compare the Efficacy of Three Different Calcaneal Osteotomies for the Correction of Heel Varus

BACKGROUND

Cavovarus deformity of the hindfoot is typically caused by neurologic disorders. Multiple osteotomies have been described for the correction of varus deformity but without clinical comparison. In this study, we used 18 identical 3-dimensional (3D) prints of a patient with heel varus to compare the operative correction obtained with Dwyer, oblique, and Z osteotomies.

METHODS

A computed tomography (CT) scan of a patient with heel varus was used to create 18 identical 3D prints of the talus, calcaneus, and cuboid. Coordinate frames were added to the talus and calcaneus to evaluate rotation. The prints were then divided into 3 groups of 6 models each. A custom jig precisely and accurately replicated each osteotomy. Following the simulated operations, cut models were CT scanned and compared with 6 uncut models. Measurements were calculated using multiplanar reconstruction image processing. An analysis of variance (ANOVA) was performed on the initial data to determine significant differences among the measured variables. A Tukey Studentized range test was run to compare variables that showed statistically significant differences using the ANOVA.

RESULTS

The coronal angle of the Dwyer and oblique osteotomies was significantly less than that of the Z osteotomy ( P < .05). The axial angle, lateral displacement, and calcaneal shortening of the uncut model and Z osteotomy were significantly less than the Dwyer and oblique osteotomies.

CONCLUSIONS

Dwyer, oblique, and Z osteotomies did not create either lateral translation or coronal rotation without the addition of a lateralizing slide or rotation of the posterior tuberosity.

CLINICAL RELEVANCE

Dwyer and oblique osteotomies would be best suited for mild deformity, yet the amount of calcaneal shortening must be acknowledged. A Z osteotomy is a complex procedure that has the capability of correcting moderate-severe coronal plane rotation but fails to provide lateralization of the pull of the Achilles insertion.

CT and MR Imaging of the Postoperative Ankle and Foot

A variety of surgical procedures exist for repair of both traumatic and degenerative osseous and soft-tissue pathologic conditions involving the foot and ankle. It is necessary for the radiologist to be familiar with these surgical procedures, so as to assess structural integrity, evaluate for complicating features, and avoid diagnostic pitfalls. Adequate interpretation of postoperative changes often requires access to surgical documentation to evaluate not only the surgery itself but the expected timeline for resolution of normal postoperative changes versus progressive disease. Appropriate use of surgical language in radiology reports is another important skill set to hone and is instrumental in providing a high-quality report to the referring surgeons. The pathophysiology of a myriad of surgical complaints, beginning from the Achilles tendon and concluding at the plantar plate, are presented, as are their common appearances at computed tomography and magnetic resonance imaging. Commonly encountered entities include Achilles tendon tear, spastic equinus, nonspastic equinus, talar dome osteochondral defect, tarsal tunnel syndrome, plantar fasciitis, pes planovalgus, pes cavovarus, peroneal tendinosis, lateral ligament complex pathology, Morton neuroma, plantar plate tear, and metatarsophalangeal joint instability. Computer-generated three-dimensional models are included with many of the procedures to provide a more global view of the surgical anatomy. Correlation with intraoperative photographs is made when available. When appropriate, discussion of postoperative complications, including entities such as infection and failure of graft integration, is presented, although a comprehensive review of postoperative complications is beyond the scope of this article. Notably absent from the current review are some common foot and ankle procedures including hallux valgus and hammertoe corrections, as these are more often evaluated radiographically than with cross-sectional imaging. ^©RSNA, 2016.

The adult cavus foot

Cavovarus deformity can be classified by the severity of malalignment ranging from a subtle and flexible to a severe and fixed cavovarus deformity of the foot.In the mild cavovarus foot, careful clinical assessment is required to identify the deformity.Weight-bearing radiographs are necessary to indicate the apex of the deformity and quantify the correction required.Surgery is performed when conservative measures fail and various surgical procedures have been described, including a combination of soft-tissue releases, tendon transfers and osteotomies, all with the aim of achieving a plantigrade and balanced foot.Joint-sparing surgery is the best option in flexible cavovarus foot even in Charcot-Marie-Tooth (CMT) disease (peroneal muscular atrophy).Arthrodesis is indicated in severe rigid cavus foot or in degenerative cases. Cite this article: EFORT Open Rev 2017;2. DOI: 10.1302/2058-5241.2.160077. Originally published online at www.efortopenreviews.org.

Neurologic Deficit Associated With Lateralizing Calcaneal Osteotomy for Cavovarus Foot Correction

BACKGROUND

Lateralizing calcaneal osteotomy (LCO) is a frequently used technique to correct hindfoot varus deformity. Tibial nerve palsy following this osteotomy has been described in case reports but the incidence has not been quantified.

METHODS

Eighty feet in 72 patients with cavovarus foot deformity were treated over a 6-year span by 2 surgeons at their respective institutions. Variations of the LCO were employed for correction per surgeon choice. A retrospective chart review analyzed osteotomy type, osteotomy location, amount of translation, and addition of a tarsal tunnel release in relation to the presence of any postoperative tibial nerve palsy. Tibial nerve branches affected and the time to resolution of any deficits was also noted.

RESULTS

The incidence of neurologic deficit following LCO was 34%. With an average follow-up of 19 months, a majority (59%) resolved fully at an average of 3 months. There was a correlation between the development of neurologic deficit and the location of the osteotomy in the middle third as compared to the posterior third of the calcaneal tuber. We found no relationship between the osteotomy type, amount of correction, or addition of a tarsal tunnel release and the incidence of neurologic injury.

CONCLUSIONS

Tibial nerve palsy was not uncommon following LCO. Despite the fact that deficits were found to be transient, physicians should be more aware of this potential problem and counsel patients accordingly. To decrease the risk of this complication, we advocate extra caution when performing the osteotomy in the middle one-third of the calcaneal tuberosity. Although intuitively the addition of a tarsal tunnel release may protect against injury, no protective effect was demonstrated in this retrospective study.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

[Dwyer osteotomy : Lateral sliding osteotomy of calcaneus]

OBJECTIVE

To correct the underlying inframalleolar varus deformity and to restore physiologic biomechanics of the hindfoot.

INDICATIONS

Neurologic, posttraumatic, congenital, and idiopathic cavovarus deformity. In patients with end-stage ankle osteoarthritis with varus heel malposition as additional single-stage procedure complementing total ankle replacement. Severe peroneal tendinopathy with concomitant cavovarus deformity.

CONTRAINDICATIONS

General surgical or anesthesiological risks, infections, critical soft tissue conditions, nonmanageable hindfoot instability, neurovascular impairment of the lower extremity, neuroarthropathy (e. g., Charcot arthropathy), end-stage osteoarthritis of the subtalar joint, severely reduced bone quality, high age, insulin-dependent diabetes mellitus, smoking.

SURGICAL TECHNIQUE

The lateral calcaneus cortex is exposed using a lateral incision. The osteotomy is performed through an oscillating saw. The posterior osteotomy fragment is manually mobilized and shifted laterally. If needed, a laterally based wedge can be removed and/or the osteotomy fragment can be translated cranially. The osteotomy is stabilized with two cannulated screws, followed by wound closure.

POSTOPERATIVE MANAGEMENT

A soft wound dressing is used. Thromboprophylaxis is recommended. Patient mobilization starts on postoperative day 1 with 15 kg partial weight bearing using a stabilizing walking boot or cast for 6 weeks. Following clinical and radiographic follow-up at 6 weeks, full weight bearing is initiated step by step.

RESULTS

Between January 2009 and June 2013, a Dwyer osteotomy was performed in 31 patients with a mean age of 45.7 ± 16.3 years (range 21.5-77.4 years). All patients had a substantial inframalleolar cavovarus deformity with preoperative moment arm of the calcaneus of -17.9 ± 3.3 mm (range -22.5 to -10.5 mm), which has been improved significantly to 1.6 ± 5.9 mm (range -16.9 to 9.9 mm). Significant pain relief from 6.3 ± 1.9 (range 4-10) to 1.1 ± 1.1 (range 0-4) using the visual analogue scale was observed. The American Orthopaedic Foot and Ankle Society score significantly improved from 33.1 ± 14.2 (range 10-60) to 78.0 ± 10.5 (range 55-95).