Neglected medial swivel dislocation of talonavicular joint with calcaneus, cuboid and 5th metatarsal fractures – A case report

Abstract

Talonavicular dislocation is a rare injury. Isolated medial or lateral talonavicular dislocations without disruption of subtalar joint are known as medial or lateral swivel dislocations respectively, both being extremely rare. We describe a rare case of neglected medial swivel dislocation with concomitant calcaneus, cuboid and 5th metatarsal fracture, which was managed with open reduction and fixation of talonavicular joint with k-wires and an external distractor. At 1 year follow up the patient was mobilizing full weight bearing without any pain or deformity, the radiographs showing well located talonavicular joint and healed calcaneus, cuboid and 5th metatarsal fractures. This is the first reported case of medial swivel talonavicular dislocation with associated calcaneum, cuboid and 5th metatarsal fracture to the best of our knowledge. This case report highlights the importance of maintaining high level of suspicion for diagnosing midfoot injuries in a polytraumatized patient as well as need of accurate and timely reduction of dislocation for good functional outcome.

Level of clinical evidence

Level 4.

1. Introduction

The mid tarsal joint, comprising the talo-navicular joint and the calcaneo-cuboid joint, is a synovial joint lying transversely across medial and lateral longitudinal arches of foot.¹ Talonavicular dislocations without involving fracture of this joint or subtalar dislocations are extremely rare. Jowett et al. described a unique variety of medial TNJ dislocation, called the medial swivel dislocation, in which the foot swivels underneath the talus medially, with interosseous talocalcaneal ligament as the axis, leaving the subtalar and calcaneo-cuboid joint intact.¹ Such injuries have been ascribed to a high energy mechanism resulting in a medially directed force to the forefoot.¹ We describe an unusual case of neglected medial swivel dislocation with associated calcaneal, cuboid and 5th metatarsal fracture which is the only reported case of such kind in literature to the best of our knowledge.

1.1. Case report

A 20 yr old female presented to us with pain on movement and deformity of right foot following fall from a height of 10 feet seven weeks back. Medical records from an outside hospital revealed that the patient suffered from right sub-trochanteric femur fracture, calcaneus fracture, cuboid fracture and 5th metatarsal fracture. Sub-trochanteric femur fracture was treated with intra-medullary nailing two days after the injury. 5th metatarsal, cuboid and calcaneus fracture was managed with below knee plaster cast. The patient was mobilizing non-weight bearing 6 weeks post-injury. On noting pain and deformity in right foot after removal of plaster cast (6 weeks post-injury), patient was referred to our institution.

On clinical examination, there was tenderness in midfoot and hindfoot, shortening of the medial column, unusual bony prominence on medial aspect and broadening of heel. No scar marks were observed. Radiographs of the involved foot revealed a uniting calcaneus fracture, fracture base of 5th metatarsal and medial dislocation of talonavicular joint (Fig. 1). The subtalar and calcaneo-cuboid joint were intact. A CT scan was done which confirmed the x ray findings and showed an undisplaced cuboid fracture (Fig. 2). Radiographs of right thigh were also taken which showed healing at fracture site with nail in situ (Fig. 3).

Fig. 1.

Radiographs taken at time of presentation 7 weeks post injury a.) anteroposterior view b.) lateral view c.) oblique view.

Fig. 2.

Non-contrast computed tomography showing dislocated talonavicular joint (a) and intact calcaneocuboid and subtalar joints (b, c) and healing calcaneus, undisplaced cuboid and 5th metatarsal fracture.

Fig. 3.

Anteroposterior (a) and lateral (b) view of Healing Right subtrochanteric femur fracture with nail in situ.

Open reduction of the talonavicular joint was planned. Under spinal epidural anaesthesia and tourniquet control, a distractor was applied along the medial column of foot and maximum length of the medial column was achieved. A 5cm anteromedial longitudinal incision was made centered over the talonavicular joint. Plane was created between extensor hallucis longus tendon and dorsalis pedis medially and extensor digitorum longus tendon laterally exposing the dislocated talonavicular joint. Talar and navicular joint surfaces were visualized and no cartilage injury was detected. Naviculum was reduced over talar head with traction and a laterally directed force and held with 3 k-wires. The distractor was retained after reduction and closure was done in layers. No splint was provided. Radiographs were obtained on day 1 (Fig. 4). Operative wound was inspected on day 2. Non weight bearing mobilization was started on day 2.

Fig. 4.

Radiographs taken on post-operative day 1 showing located well talo-navicular joint held with 3 K-wires and medial column distraction using an external distractor (a – anteroposterior view of right ankle, b-anteroposterior view of right foot, c-lateral view of right foot).

The patient was discharged on day 4. No wound complications were encountered. The external distractor was removed at 4 weeks and K-wires were removed at 6 weeks post-operatively. Gradual weight bearing was started at 6 weeks postoperatively. Full weight bearing was initiated at 3 months post-operatively (Fig. 5). At 1 year follow up the patient was mobilizing full weight bearing without support (Fig. 6). There were no complaints of pain or deformity. Radiographs at 1 year follow-up showed well located talonavicular joint and healed calcaneus, cuboid and 5th metatarsal fractures (Fig. 7).

Fig. 5.

Anteroposterior and lateral view of right femur with hip showing healed subtrochanteric fracture at 3 months post-operatively.

Fig. 6.

Clinical images at 1 year post-operatively showing patient able bear weight fully with no deformity of right foot.

Fig. 7.

Radiographs taken at 1 year post-operatively showing well located talo-navicular joint and healed calcaneus, cuboid and 5th metatarsal fracture.

2. Discussion

Mid-foot injuries are a rare estimated at 3.6/100000/year missed or misdiagnosed 41% of time.² Main and Jowett classified mid-tarsal injuries by the direction of displacement (and the implied direction of the applied force). In their patients, medial and lateral displacement, longitudinal impact injuries, plantar displacement, and crush injuries occurred. They included medial swivel dislocations in the subtype of medial displacements in which the force is directed medially causing the foot to rotate underneath the talus on an intact talocalcaneal ligament.¹ The force being applied distal to the subtalar joint leaves it and calcaneocuboid joint intact and dislocates the talo-navicular joint.¹

Medial swivel dislocations have been described previously in case reports. Jowett et al. presented a series of 6 such cases, however, associated injuries were not commented upon.¹ William et al. described this dislocation with a cuboid fracture.³ Inal et al. described a case with fracture of 4th and 5th metatarsal and ascribed a medially directed force to be responsible for the fracture as well as dislocation.⁴ Powell et al. described a cuboid and navicular fracture along with the medial TNJ dislocation.⁵ Pehlivan et al. described a concominant talar head fracture.⁶ Dutt et al. described a neglected pure medial swivel dislocation without associated fractures.⁷

In the present case, however, medial swivel dislocation has occurred with a 5th metatarsal, cuboid and calcaneum fracture which, in our knowledge, has not been described before. We ascribe this injury to a dual mechanism. A medially directed force, firstly, causing the 5th metatarsal fracture and medial swivel dislocation on an intact talo-calcaneal ligament, secondly followed by an axial compression force causing the calcaneum to fracture.

Various treatment options have been described in the literature. Richter et al., in their prospective study of midfoot injuries, recommended that early and anatomic open reduction are important for a good functional outcome.⁸ Jowett et al. described a poor result requiring arthrodesis in cases in which closed reduction and plaster immobilization was utilized and good to fair result in open reduction category for medial swivel dislocations.¹ Other case reports recommend immediate closed reduction with plaster cast immobilization pertinent for good results.^3,4,9 Open reduction and internal fixation, however, must be employed in cases that not amenable to close reduction. Dutt et al. described favourable result in a neglected medial swivel dislocation with open reduction and fixation with K-wires.⁷

Due to the neglected nature of the present case, we did an open reduction of talonavicular joint with an assistance of a medial column distractor. Since the articular cartilage was found intact we decided against a primary arthrodesis and fixed the joint with k-wires.

We recommend a high index of suspicion for complex mid-foot injuries in patients suffering high energy trauma like fall from height. A complete clinico-radiological assessment is extremely important to avoid missing talonavicular joint dislocations. Early reduction and anatomical reduction of associated fractures, whenever possible, should be stressed upon for favourable results. We recommend use of a distracting device for medial column in neglected cases for the ease of reduction without damaging the articular surface.

Conflicts of interest

None.

Funding

None.

Appendix A. Supplementary data

The following is the supplementary data to this article: