Arthroscopic Excision of Bone Fragments in a Neglected Fracture of the Lateral Process of the Talus in a Junior Soccer Player

Abstract

Fractures of the lateral process of the talus are uncommon and often overlooked. Typically, they are found in adult snowboarders. We report the case of an 11-year-old male soccer player who complained of lateral ankle pain after an inversion injury 6 months earlier. He did not respond to conservative treatment and thus underwent arthroscopic excision of fragments of the talar lateral process. The ankle was approached through standard medial and anterolateral portals. A 2.7-mm-diameter 30° arthroscope was used. Soft tissues around the talus were cleared with a motorized shaver, and the lateral aspect of the talar process was then visualized. The lateral process presented as an osseous overgrowth, and a loose body was impinged between the talus and the calcaneus. The osseous overgrowth was resected piece by piece with a punch, and the loose body was removed en block. The patient returned to soccer 5 weeks after the operation. This case exemplifies 2 important points: (1) This type of fracture can develop even in children and not only in snowboarders. (2) Arthroscopic excision of talar lateral process fragments can be accomplished easily, and return to sports can be achieved in a relatively short time.

Fractures of the lateral process of the talus (LPT) are encountered infrequently.^1-5 Although they are found typically in adult snowboarders, the incidence of LPT fractures has been growing in frequency over the past few years, even in the pediatric population.⁶ This injury is commonly misdiagnosed on the initial radiographs, and overlooking it can lead to subtalar osteoarthritis.^2-4,7-9 In the case of a symptomatic nonunion, open removal of small fragments is generally recommended.^2,6-9 We report arthroscopic excision of a bone fragment and loose body of the LPT in an 11-year-old male soccer player.

Case Presentation

An 11-year-old boy presented with a history of twisting his right ankle during a soccer game 6 months earlier. He was diagnosed with an ankle sprain (inversion injury), and treated nonoperatively by immobilization with taping, and allowed full weight bearing. He became pain free while performing his daily and sporting activities, and he continued to play soccer 6 times a week with no complaints of his ankle disability. He visited our clinic initially with a complaint of lateral ankle pain after another player stomped on our patient's foot during a game, as well as a twisting inversion injury of the right ankle that had occurred the day before, also during a soccer game. On physical examination, an osseous prominence 1 cm distal to the tip of the lateral malleolus was palpable, with local tenderness, but swelling was not remarkable. The lateral ankle pain was intensified when the subtalar joint was forced into inversion and eversion. The ankle joint radiographs with an anteroposterior view showed a nonunion of the LPT and an oval-shaped bone fragment in the talocalcaneal joint (Fig 1). Computed tomography (CT) showed a minimally displaced hypertrophic 1-cm bone fragment and a loose body (11 × 12 × 5 mm) between the LPT and calcaneus (Fig 2). Short tau inversion recovery magnetic resonance imaging showed increased signal intensity in the metatarsal and cuneiform bones indicating bone marrow edema, although no change in signal intensity was observed in the area surrounding the previous LPT fracture. Altogether, the findings indicated an old LPT fracture and additional bone fragment presenting as a loose body within the talocalcaneal joint. A short cast was applied with no weight bearing for 2 weeks to reduce the acute inflammatory response. Range-of-motion and muscle-strengthening exercises followed by jogging were permitted, and the patient returned to playing soccer 4 weeks after the last injury. Although his score on the Ankle-Hindfoot Scale was 86 points, he was not able to run at full speed and could not perform quick turns because of persistent lateral ankle pain. Because the symptoms did not improve with conservative treatment, arthroscopic removal of the bone fragments was planned.

Fig 1.

Anteroposterior and lateral radiographs of the right ankle joint taken during the initial visit (6 months after the injury with fracture of the lateral process of the talus during a soccer game) showing a fracture of the lateral process of the talus (black arrow) and an isolated bone fragment involving the talocalcaneal joint (white arrow).

Fig 2.

Coronal reconstructed computed tomography images confirm the bone fragment in the talocalcaneal joint and nonunited fracture of the lateral process of the talus involving both the talo-peroneal and subtalar joints.

Surgical Technique

The operation was performed with the patient under general anesthesia in the supine position. After attachment of a pneumatic cuff, 5 mL of normal saline solution was injected into the sinus tarsi. The anterolateral portal was first inserted 2 cm anterior and 1 cm distal to the tip of the lateral malleolus, the location equivalent to the position of the sinus tarsi. This anterolateral portal was used as the visualization portal. A 2.7-mm-diameter 30° arthroscope was used. Next, a medial portal was established just distal and anterior to the tip of the lateral malleolus and was used as a working portal. Soft tissues around the talus were removed with a motorized shaver (3.5-mm cutter; Stryker, Kalamazoo, MI), and the lateral aspect of the subtalar joint and the articular aspect of the calcaneofibular ligament were then visualized (Fig 3A, Video 1). The loose body impinged between the talus and the calcaneus was also well visualized (Fig 3B). The distal fragment of the fractured LPT was removed with a small punch. When it became difficult to determine whether the fragment was being correctly resected, the position of the instrument was confirmed with fluoroscopy. After partial resection of the LPT, a freely movable loose body was well visualized (Fig 4) and totally removed with the punch. Additional resection of the LPT was performed with the punch. Shaving of synovitis-affected tissue was performed with a radiofrequency system (VAPR; DePuy Mitek, Raynham, MA). The intra-articular space was irrigated, the portals were sutured, and an elastic bandage was applied.

Fig 3.

Arthroscopic examination of LPT and loose body (supine position, right ankle, viewed from anterolateral portal). (A) After the soft tissues around the talus were cleared, the lateral aspect of the talar process that presented as an osseous overgrowth and the articular aspect of the calcaneofibular ligament were visualized. (B) A loose body impinged between the talus and the calcaneus was well visualized. (C, calcaneus; CFL, calcaneofibular ligament; LB, loose body; LPT, lateral process of the talus.)

Fig 4.

Arthroscopic view of loose body after partial resection of LPT (supine position, right ankle, viewed from anterolateral portal). After partial resection of the LPT, a freely movable loose body was well visualized. (C, calcaneus; LB, loose body.)

The patient was mobilized with weight bearing 5 days after the operation, and he was allowed to jog at 2 weeks and play soccer at 5 weeks. No hypertrophic bone fragments or loose bodies were observed on CT scans taken 1 month after surgery (Fig 5). At the final follow-up 12 months after surgery, the patient was asymptomatic with a full range of motion and a 100-point score on the Ankle-Hindfoot Scale. He has returned to regular soccer playing with a semiprofessional junior team.

Fig 5.

Coronal reconstructed computed tomography images taken 1 month after surgery with no bone fragments observed.

Discussion

Fractures of the lateral process account for 26% of all talar fractures² and 0.4% to 1% of all ankle injuries.^1,9,10 They typically have been seen in adult snowboarders^1,7,11 but have been increasing in frequency over the past few years in the pediatric population.⁶ Our patient was an 11-year-old boy who sustained an injury during a soccer game. The pathomechanism of this fracture is multifactorial and is not fully defined. We should keep in mind that this fracture can occur even in a child participating in sports disciplines other than snowboarding. Another characteristic feature of this fracture is that it is often overlooked and untreated, with as many as 46% of fractures initially being missed.^2,4,5,9 This can lead to persistent pain and subsequent post-traumatic subtalar osteoarthritis.^3,4,7-9 Our patient was misdiagnosed as having an ankle sprain after his first injury 6 months before the initial visit to our clinic. After the second injury and on the first visit to our clinic, CT showed fracture nonunion and a loose body in the talocalcaneal joint. Although magnetic resonance imaging is not mandatory for diagnosis of this fracture, it was helpful to determine whether the second injury was causative for or contributed to the fracture. Because high signal intensity on the short tau inversion recovery magnetic resonance imaging scans was not observed at the fracture site and in the surrounding tissues, the initial trauma was considered the cause of the fracture. Although a detailed evaluation of the initial injury could not be performed, the fracture was suspected to be a type II fracture according to the Hawkins classification.² After the initial injury, the patient improved and was pain free; however, he was uncomfortable during sporting activities. The reason he responded to conservative therapy after the initial injury but did not respond to conservative therapy after the second injury remains unclear. We speculate that a fibrous union of the fracture temporarily improved the symptoms and the patient did not complain of pain after immobilization, but one of the fractured fragments separated from the talus as a larger loose body and remained within the talocalcaneal joint. When the second injury occurred, the nonunion worsened and the loose body impinged between the talus and the calcaneus, leading to joint instability. Although there is still controversy regarding the treatment of fresh type I and III fractures with early debridement, excision was selected in our patient because many authors recommend early excision of nonunited fractures presenting late, especially when the bone fragments are small.^2,6-8 Instability of the subtalar or ankle joint was not reported after excision of the fragments.

The advantage of arthroscopic surgery was good direct and dynamic visualization of the lateral aspect of the talus and its pathology without any damage to the anterior talofibular, calcaneofibular, and talocalcaneal ligaments caused by the surgical procedure. The clear-cut approach, successful surgery, and proper postoperative rehabilitation allowed early recovery and return to sporting activity. In addition, the applied method was simple and cost-effective; the arthroscopic excision did not require additional implants. For a surgeon familiar with arthroscopic visualization, the procedure can be performed quickly and safely.

There are, however, several potential limitations and complications associated with the arthroscopic approach. First, it can be difficult to determine whether the fragments have been totally resected during surgery. In such cases, the position of the instrument must be confirmed under both arthroscopy and fluoroscopy. Second, there is a risk of damage to the superficial peroneal nerve and sural nerve. With careful palpation of the lateral malleolus and sinus tarsi before insertion of the portal, the risk of serious complications can be reduced (Table 1).

Table 1.

Technical Tips, Indications, and Risks for Arthroscopic Excision of Bone Fragments of LPT Fracture

Technical tips Use a 2.7-mm-diameter 30° arthroscope. Saline solution is injected into the sinus tarsi to facilitate insertion of an arthroscope into the lateral talar space. Use the anterolateral portal as a viewing portal and the medial portal as a working portal. When it is difficult to determine whether the fragment is being correctly resected, the position of the instrument should be confirmed under both arthroscopy and fluoroscopy. Indication Excision of small fragments of LPT fracture and/or loose body that developed due to fracture Risks Damage to superficial peroneal and sural nerves Benefits Simple and cost-effective method with no need for additional implants

(LPT, lateral process of the talus.)

Fractures of the LPT are still relatively rare. Arthroscopic excision of the fragments should be considered a plausible choice in determining the surgical method, which can be accomplished easily, allowing the patient an early return to preoperative sporting activities.

Supplementary Data

Video 1

Arthroscopic excision of bone fragments in the neglected fracture of the LPT in an 11-year-old soccer player. The procedure was carried out using the anterolateral portal as a viewing portal and the medial portal as a working portal. The lateral aspect of the talar process presented as an osseous overgrowth, and a loose body was impinged between the talus and calcaneus. They were resected totally by use of simple instruments under both arthroscopic and fluoroscopic assistance.