The use of a portable CT scanner for the intraoperative assessment of talocalcaneal coalition resections

Surgical Treatment of Calcaneonavicular and Talocalcaneal Coalitions

Tarsal coalition is determined by an absence of segmentation between one or more foot bones. The main symptom is activity-related foot pain, usually dorsolateral for calcaneonavicular coalitions and medial for talocalcaneal ones. At presentation, a symptomatic tarsal coalition must be treated conservatively for at least 6 months. If the conservative treatment fails and the foot is still painful, resection is the treatment of choice. Advantage of surgery is to restore mobility and reduce the risk of subsequent degenerative arthritis. Common pitfalls of surgery include failure to recognize associated coalitions, inadequate or extensive resection, and injury of adjoining bones.

Preoperative Guidance With Weight-Bearing Computed Tomography and Patient-Specific Instrumentation in Foot and Ankle Surgery

The use of preoperative and intraoperative guidance in foot and ankle surgery has grown substantially in recent years. Weight-bearing computed tomography (WBCT) and patient-specific instrumentation (PSI) are used in total ankle arthroplasty (TAA) to achieve precise bone cutting and implant positioning, and intraoperative 3-dimensional (3D) imaging has been used to reduce complications and improve clinical outcomes in other foot and ankle surgical procedures. This narrative review of the literature focuses on the evidence supporting the use of WBCT and PSI in TAA and looks at other promising technologies used to guide foot and ankle surgery.

Does the use of intraoperative CT scan improve outcomes in Orthopaedic surgery? A systematic review and meta-analysis of 871 cases

BACKGROUND

Intraoperative imaging is frequently made use of in Orthopaedic surgery. Historically, conventional 2-dimensional fluoroscopy has been extensively used for this purpose. However, 2D imaging falls short when it is required to visualise complex anatomical regions such as pelvis, spine, foot and ankle etc. Intraoperative 3D imaging was introduced to counter these limitations, and is increasingly being employed in various sub-specialities of Orthopaedic Surgery.

OBJECTIVES

This review aims to outline the clinical and radiological outcomes of surgeries done under the guidance of intraoperative 3D imaging and compare them to those done under conventional 2D fluoroscopy.

METHODS

Three electronic databases (PubMed, Embase and Scopus) were searched for relevant studies that directly compared intraoperative 3D imaging with conventional fluoroscopy. Case series on intraoperative 3D imaging were also included for qualitative synthesis. The outcomes evaluated included accuracy of implant placement, mean surgical duration and rate of revision surgery due to faulty implants.

RESULTS

A total of 31 studies from sub-specialities of spine surgery, pelvi-acetabular surgery, foot and ankle surgery and trauma surgery, having data on a total of 658 patients were analysed. The study groups which had access to intraoperative 3D imaging was found to have significantly increased accuracy of implant positioning (Odds Ratio 0.35 [0.20, 0.62], p = 0.0002) without statistically significant difference in mean surgical time (p = 0.57). Analysis of the studies that included clinical follow up showed that the use of intraoperative 3D imaging led to a significant decrease in the need for revision surgeries due to faulty implant placement.

CONCLUSION

There is sufficient evidence that the application of intraoperative 3D imaging leads to precise implant positioning and improves the radiological outcome. Further research in the form of prospective studies with long term follow up is required to determine whether this superior radiological outcome translates to better clinical results in the long run.

Operative versus nonoperative treatment in children with painful rigid flatfoot and talocalcaneal coalition

Background

The management of painful rigid flatfoot (RFF) with talocalcaneal coalition (TCC) is controversial. We aimed to compare operative and nonoperative treatment in children with RFF and TCC.

Methods

We retrospectively reviewed medical records and radiographs of children with RFF and TTC treated between 2005 and 2015. The nonoperative treatment consisted of manipulation under anesthesia, cast immobilization and shoe insert after cast removal. The operative treatment consisted of combined TCC resection, graft interposition and subtalar arthroereisis.

Results

Thirty-four children (47 ft) in the nonoperative group and twenty-one children (34 ft) in the operative group were included. No differences were found between groups, concerning baseline characteristics. The mean age at treatment was 11.8 years (9–17): 11.6 (9–17) for the nonoperative group, 12.2 (10–15) for the operative group. The mean follow-up averaged 6.6 (3–12) years and was significantly longer in the nonoperative group (7.8 versus 4.7 years; p < 0.0005), since the operative procedure was increasingly practiced in the latest years.

There were no complications in either groups, but 6 patients (7 ft) in the nonoperative group were unsatisfied and required surgery. At the latest follow-up, the AOFAS-AHS improved in both groups, although the operative group showed significantly better improvement. The operative group reported also significantly better FADI score, after adjustment for follow-up and baseline variables.

Conclusion

The operative treatment showed better results compared to the nonoperative treatment. Symptomatic RFF with TCC in children can be effectively treated in one step with resection, graft interposition and subtalar arthroereisis. Further prospective randomized studies are needed to confirm our findings and to identify the best operative strategy in this condition.

Intraoperative Three-Dimensional Navigation for Talocalcaneal Coalition Resection

Talocalcaneal tarsal coalitions are a common source of foot pain, stiffness, and deformity. These coalitions are treated symptomatically with rest and periods of immobilization. When those measures fail, surgical resection is attempted. This procedure is an anatomic challenge with the consequence of leaving residual coalition. The residual coalition primarily results from difficulty with intraoperative imaging because fluoroscopy does not provide adequate detail of this area. Some investigators have recommended intraoperative computed tomography after resection with reasonable results. We describe the combination of an intraoperative computed tomography with a navigated instrument system for resection of talocalcaneal coalitions. The use of a navigated probe and burr aids in defining the most anterior, posterior, and medial extents of the coalition. This technique reduces the morbidity, with less bone removed and preservation of intact subtalar articulations and allows for an efficient, thorough, and controlled resection.

The "Double Medial Malleolus": A New Physical Finding in Talocalcaneal Coalition

PURPOSE

It has been the observation of the senior author that there is a bony fullness or "double medial malleolus" over the middle facet as a consistent finding with most talocalcaneal coalitions (TCC). To document this observation, we reviewed records and radiographs in 3 patient groups.

METHODS

Part 1: retrospective chart review was completed for 111 feet to determine the clinical presence of a palpable "double medial malleolus." Part 2: computed tomography (CT) scans for evaluation of tarsal coalition or symptomatic flatfoot between January 2006 and December 2014 were retrospectively reviewed for the same cohort. Soft tissue thickness was measured as the shortest distance between bone and skin surface at both the medial malleolus and the middle facet/coalition. The volume of the middle facet or coalition was measured at their midpoint. These findings were compared among feet with TCC (n=53), calcaneonavicular coalition (CNC) (n=20), and flatfoot (n=38).

RESULTS

Part 1-clinical: from medical records, 38 feet (34%) had documented record of a palpable medial prominence. Of the feet reviewed with a "double medial malleolus," all had TCC (no false positives or false negatives). Clinical and CT prominence demonstrated significant correlation (rs=0.519, P=0.001). Part 2-radiographic: CT observation of "double medial malleolus" is significantly associated with TCC (P<0.001). CT observation of double medial malleolus is 81% sensitive and 79% specific as a predictive test for TCC. The middle facet-to-skin distance was significantly closer in those with TCC versus controls (P<0.001). The ratio was larger in patients with TCC versus CNC (P=0.006) or flatfeet (P<0.001). Volume was nearly twice the size in patients with TCC versus the controls (P<0.001).

CONCLUSIONS

TCCs have a bony prominence below the medial malleolus on clinical exam and CT scan not present in flatfeet or CNCs. This abnormal middle facet is almost twice the size of the normal middle facet. Obesity or severe valgus may mask this finding. If a palpable bony prominence is noted just below the medial malleolus during examination of a painful foot with a decrease in subtalar motion, the likely diagnosis is TCC. With this added clinical finding, appropriate images can be ordered to confirm the diagnosis of the latter. We advise CT scans with 3D images for surgical planning. The primary finding for tarsal coalitions in textbooks is decreased subtalar motion. This new finding of a palpable enlarged medial prominence just below the medial malleolus is highly associated with TCCs.

LEVEL OF EVIDENCE

Level III.

Subtalar coalition resection utilizing live navigation: a technique tip

PURPOSE

Describe the surgical technique of talocalcaneal coalition resection using live CT navigation.

METHODS

A ten-year-old female with left talocalcaneal coalition hindfoot pain refractory to conservative management underwent surgical coalition resection using live CT navigation. The procedure and discussion of this technique is described in detail.

RESULTS

With minimal radiation exposure to the patient, CT navigation for this complex talocalcaneal coalition was both helpful and potentially timesaving by allowing immediate localization and guided resection of the coalition.

CONCLUSION

In the case of a complex subtalar coalition resection, CT navigation poses minimal patient radiation exposure and allows immediate localization and guided resection of the coalition.

LEVEL OF EVIDENCE

Level V.

Surgical Reconstruction for Talocalcaneal Coalitions With Severe Hindfoot Valgus Deformity

INTRODUCTION

Coalition resection can restore motion, and improve pain in patients with talocalcaneal coalitions (TCCs) and an aligned foot. However, there is some debate regarding appropriate treatment of patients with associated valgus deformity. The purpose of this study was to present the outcomes and complications following surgical reconstruction, with or without coalition resection, in a series of patients with TCC and severe hindfoot valgus.

METHODS

Thirteen consecutive patients (14 feet) were evaluated. Eleven patients were male. Mean age was 14 years. Mean follow-up was 43.8 months. Seven patients (8 feet) underwent simultaneous resection of the coalition and reconstruction, and 6 patients (6 feet) isolated reconstruction. The talar-first metatarsal angle, the talar-horizontal angle, and calcaneal pitch were measured preoperatively and postoperatively. Clinical evaluation was made according to the American Orthopaedic Foot and Ankle Society ankle-hindfoot score.

RESULTS

All radiographic values improved significantly and were within the normal ranges postoperatively. The average American Orthopaedic Foot and Ankle Society ankle-hindfoot score had improved from 45 to 98 points (P<0.001) in the group of simultaneous resection and reconstruction, and from 60 to 92.3 points (P=0.002) in the group of isolated reconstruction. All patients were asymptomatic at the last follow-up and were satisfied with the procedure.

DISCUSSION

Surgical reconstruction with or without coalition resection can achieve significant functional and radiographic improvements, and symptoms relief in selected patients with TCCs and severe valgus deformity.

LEVEL OF EVIDENCE

Level IV-therapeutic study.

What's New in Pediatric Flatfoot?

BACKGROUND

Children with flatfeet are frequently referred to pediatric orthopaedic clinics. Most of these patients are asymptomatic and require no treatment. Care must be taken to differentiate patients with flexible flatfeet from those with rigid deformity that may have underlying pathology and have need of treatment. Rigid flatfeet in infants may be attributable to a congenital vertical talus (CVT); whereas those in older children and adolescents may be due to an underlying tarsal coalition. We performed a review of the recent literature regarding evaluation and management of pediatric flatfeet to discuss new findings and suggest areas where further research is needed.

METHODS

We searched the PubMed database for all papers related to the treatment of pediatric flatfoot, tarsal coalition, and CVT published from January 1, 2011 to December 31, 2014, yielding 85 English language papers.

RESULTS

A total of 18 papers contributed new or interesting findings.

CONCLUSIONS

The pediatric flexible flatfoot (FFF) remains poorly defined, making the understanding, study, and treatment of the condition extremely difficult.Pediatric FFF is often unnecessarily treated. There is very little evidence for the efficacy of nonsurgical intervention to affect the shape of the foot or to influence potential long-term disability for children with FFF. The treatment of tarsal coalition remains challenging, but short-term and intermediate-term outcome studies are satisfactory, whereas long-term outcome studies are lacking. Management of the associated flatfoot deformity may be as important as management of the coalition itself. The management of CVT is still evolving; however, early results of less invasive treatment methods seem promising.

LEVEL OF EVIDENCE

Level 4-literature review.

Intraoperative 3-Dimensional Computed Tomography and Navigation in Foot and Ankle Surgery

Computer-assisted orthopedic surgery has developed dramatically during the past 2 decades. This article describes the use of intraoperative 3-dimensional computed tomography and navigation in foot and ankle surgery. Traditional imaging based on serial radiography or C-arm-based fluoroscopy does not provide simultaneous real-time 3-dimensional imaging, and thus leads to suboptimal visualization and guidance. Three-dimensional computed tomography allows for accurate intraoperative visualization of the position of bones and/or navigation implants. Such imaging and navigation helps to further reduce intraoperative complications, leads to improved surgical outcomes, and may become the gold standard in foot and ankle surgery. [Orthopedics.2016; 39(5):e1005-e1010.].

Talocalcaneal Coalitions

Talocalcaneal coalitions present with complaints of flatfeet, foot or ankle pain after minor injury, or recurrent ankle sprains. Physical examination findings include limited subtalar motion and prominence inferior to the medial malleolus. Use of computed topography (CT) scan is recommended for preoperative planning. Confirmation of resection with intraoperative CT. Resection of talocalcaneal coalitions with fat-graft interposition has superior results to primary arthrodesis. Improved outcomes have been reported after resection, with foot scores averaging 90/100 (AOFAS).