Clinical Imaging xxx (2014) xxx–xxx
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Turf toe and sesamoiditis: what the radiologist needs to know☆,☆☆ Aaron J. Schein a, Matthew R. Skalski b, Dakshesh B. Patel a, Eric A. White a, Ryan Lundquist c, Christopher J. Gottsegen d, Deborah M. Forrester a, George R. Matcuk Jr. a,⁎ a
Department of Radiology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033-5313 Department of Radiology, Southern California University of Health Sciences, Whittier, CA 90604 Radiology and Imaging Consultants, Colorado Springs, CO 80903 d Department of Radiology, New York University, Langone Medical Center, New York, NY 10016 b c
a r t i c l e
i n f o
Article history: Received 13 September 2014 Received in revised form 8 November 2014 Accepted 11 November 2014 Available online xxxx Keywords: Turf toe Sesamoiditis First metatarsophalangeal joint complex Plantar plate
a b s t r a c t The first metatarsophalangeal (MTP) joint complex is a critical weight-bearing structure important to biomechanics. An acute dorsiflexion injury, named “turf toe,” is common among American football and soccer players. “Sesamoiditis” is a name often given for pain arising from the hallux sesamoids in the absence of acute trauma, and may result from a variety of causes. The first MTP joint complex can also be affected by degenerative or inflammatory arthritis, infarct, and infection. This review article will cover the anatomy and biomechanics of the first MTP joint complex, its patterns of injury and pathology, imaging techniques, and management. © 2014 Elsevier Inc. All rights reserved.
1. Introduction The first metatarsophalangeal (MTP) joint and its associated capsular complex are a critical weight-bearing structure important in the biomechanics of standing, running, and gait. The first MTP complex is particularly susceptible to injury among collegiate and professional American football and soccer players (commonly known as “turf toe”) but, like most other joints, is also affected by a broad range of pathology including stress and overuse, degenerative and inflammatory arthritis, infarct, and infection. Unaddressed pathology can lead to long-term morbidity and loss of function, and conservative and surgical methods have been used to effectively treat many of these disorders. The first MTP complex is made up of several small osseous, ligamentous, and musculotendinous structures, but its anatomic complexity is easily simplified by understanding its essential biomechanics. This review will cover the anatomy and biomechanics of the first MTP complex, essential imaging tools, the spectrum of injury and pathology, and current treatment methods. 2. Anatomy and biomechanics Sesamoids were first named by Galen around 180 CE due to the tiny bones’ resemblance to sesame seeds [1]. Sesamoids are small bones that ☆ Grants received: none. ☆☆ Disclosures: none. ⁎ Corresponding author. Department of Radiology, Keck School of Medicine, University of Southern California, 1500 San Pablo Street, 2nd Floor Imaging, Los Angeles, CA 900335313. Tel.: +1 323 442 8721; fax: +1 323 442 8755. E-mail address: [email protected] (G.R. Matcuk).
form entirely within tendons as they curve around joints. They may form within a joint capsule (e.g., the hallux sesamoids and patella), or they may be separated from the apposing bone by a synovial-lined bursa (e.g., the peroneus longus sesamoid). In either case, the articulating surfaces of the sesamoid and the apposing bone are lined by hyaline cartilage [2]. The hallux sesamoids typically ossify by 9–11 years of age [3]. The two hallux sesamoids arise within the paired flexor hallucis brevis (FHB) tendons (medial and lateral heads). Typically, the medial hallux sesamoid is slightly more distal than the lateral. The sesamoids sit on the plantar surface of the forefoot, directly underlying the first metatarsal head. There is a bony ridge on the undersurface of the first metatarsal head called the crista that separates the sesamoids, delineating the medial and lateral metatarsal–sesamoidal joints (Fig. 1) [4]. The medial hallux sesamoid is frequently bipartite, and the lateral sesamoid is occasionally so (Fig. 2) The hallux sesamoids elevate the first metatarsal head, providing a moment arm that augments plantar flexion of the first MTP joint [5–8]. The hallux sesamoids are inextricable from the first MTP joint capsule. A dense fibrous band deep to the flexor hallucis longus (FHL) tendon called the plantar plate connects the hallux sesamoids and the plantar base of the first proximal phalanx, forming the plantar aspect of the first MTP joint capsule (Fig. 3) [4]. The sesamoids act as a pulley to transmit force from the FHB muscles to the base of the first proximal phalanx, through the plantar plate [6–8]. An analogous plantar plate is found at the proximal base of every phalanx in the foot. The sesamoids are further anchored to the first metatarsal head and base of the proximal phalanx by the medial and lateral metatarsal–sesamoidal and sesamoidal–phalangeal ligaments, contributing along with the collateral ligaments to the medial and lateral aspects of the first MTP joint
http://dx.doi.org/10.1016/j.clinimag.2014.11.011 0899-7071/© 2014 Elsevier Inc. All rights reserved.
Please cite this article as: Schein AJ, et al, Turf toe and sesamoiditis: what the radiologist needs to know, Clin Imaging (2014), http://dx.doi.org/ 10.1016/j.clinimag.2014.11.011
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Fig. 1. Normal bony anatomy of the first MTP joint.
capsule [4]. The abductor and adductor hallucis tendons insert on the medial and lateral bases of the first proximal phalanx, respectively, and also give off small attachments to the sesamoids [1]. A small fibrous band called the intersesamoid ligament connects the medial and lateral hallux sesamoids (Fig. 4). The forces of weight bearing are distributed to the first metatarsal head by the various sesamoid ligaments and the action of the diarthrodial metatarsal–sesamoidal joints [6–8].
3. Imaging techniques Radiographic evaluation of the hallux sesamoids is performed with a combination of anterior–posterior (AP), oblique, and lateral projections. Coronal imaging of the hallux sesamoids can be helpful for profiling the metatarsal–sesamoidal joints [2]. A lateral view stress test with 45° of MTP dorsiflexion may also be performed to assess the functional integrity of the plantar plate [9]. Computed tomography (CT) may be helpful in assessing fractures, sclerosis, or bony erosion. Evaluation of the soft tissue structures, however, is best performed using magnetic resonance imaging (MRI).
Fig. 3. Normal muscles, ligaments, and tendons of the first MTP joint.
Since the first MTP joint complex is a small structure and the individual components that must be scrutinized are smaller still, strict attention to MRI parameters is advised to optimize the sensitivity and specificity of the examination. An extremity surface coil placed over the forefoot will help to improve signal to noise ratio, and an appropriately small field of view will increase spatial resolution. Imaging at 3-T field strength provides optimal signal to noise ratio, but imaging at 1.5-T field strength is adequate and more readily available. Imaging parameters vary from institution to institution, but ideally, the field of view should be between 10 and 14 cm, slice thickness should be 3 mm, and there should be an interslice gap of 0.3 mm (10%) [10]. A thorough examination includes non-fat-suppressed T1-weighted (T1W) or proton density (PD) images in conjunction with fluidsensitive fat-suppressed PD (PDFS) or short tau inversion recovery (STIR) images, performed in coronal (short axis of foot), axial (long
Fig. 2. Oblique views of normal bipartite medial (a) and lateral (b) hallux sesamoids in different patients.
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players. It was described as a hyperextension (dorsiflexion) injury to the first MTP complex and was felt to result from the combination of flexible sole cleats being used on hard, artificial turf. Turf toe results from axial loading forces applied to the forefoot while the first MTP joint is in the equinovarus (tiptoe) position (Fig. 5) [14]. Injuries occur along a spectrum of severity from low-grade capsular sprains to highgrade capsular and ligamentous tears, and may be complicated by MTP joint malalignment (usually in the form of hallux valgus), subluxation, and sesamoid fractures. Although much emphasis is given to turf toe, chronic degenerative disease can also lead to plantar plate injury. 4.1. MRI findings
Fig. 4. Short-axis T1W image through the first metatarsal head, showing normal anatomy.
axis of foot), and parasagittal planes. Both non-fat-suppressed T1W and PD sequences are well suited for visualizing ligaments and tendons, but T1W sequences provide an accurate map of normal marrow fat, while PD images provide superior imaging of the chondral surfaces. Fluidsensitive PDFS and STIR images are sensitive to edema and help to demonstrate acute traumatic, degenerative, or inflammatory changes. PDFS images take less time to acquire and have better signal to noise ratio than STIR, but homogeneous fat suppression is easier to achieve with STIR. Thus, STIR is preferred in situations where homogeneous fat suppression is difficult to achieve, such as in postoperative patients with micrometallic debris in the surgical bed. Routine intravenous contrast is not necessary, but it is helpful in the evaluation of tumor or infection [10,11]. Toe traction and MR arthrography may offer an improved assessment in some cases [12,13].
MRI is a useful and accurate tool for evaluating plantar plate injuries. The normal plantar plate appears as a dense band of low signal connecting the hallux sesamoids (or the metatarsal head in the case of the lesser metatarsals) to the plantar base of the proximal phalanx and is seen best on sagittal and short-axis images (Fig. 6). MRI findings in plantar plate injury vary with the severity and acuity of the injury. Full-thickness plantar plate tears will appear as focal discontinuity of the plantar plate with retraction and a fluid gap (Fig. 7), whereas sprains and partial thickness tears may show either thinning or thickening with indistinctness of the plantar plate (Figs. 8–9). However, care must be taken not to overcall partial tears, as plantar plate recesses can be seen
4. Turf toe and associated injuries Turf toe was first described by Bowers and Martin in 1976 as a plantar capsular sprain of the first MTP joint in collegiate American football
Fig. 5. Illustration of the mechanism of a turf toe injury. Axial loading forces are applied to the first MTP joint while in the equinovarus position.
Fig. 6. Sagittal T1W and PDFS images of the first MTP plantar plate (a), second MTP plantar plate (b), and interphalangeal plantar plates (c).
Please cite this article as: Schein AJ, et al, Turf toe and sesamoiditis: what the radiologist needs to know, Clin Imaging (2014), http://dx.doi.org/ 10.1016/j.clinimag.2014.11.011
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Fig. 7. An 18-year-old man with acute plantar plate tear. Sagittal PDFS (a) and T1W (b), and short-axis STIR (c) images show disruption of the first MTP plantar plate (arrows) and retraction of the medial hallux sesamoid (arrowheads), with associated edema. Normal FHL tendon (asterisk).
at the proximal phalangeal attachment as a normal variant [15]. Proximal retraction of the sesamoids is expected in cases of complete plantar plate tear and may be detected with lateral radiographs with the great toe stressed in dorsiflexion [9]. Acute injuries will usually demonstrate associated soft tissue edema, while chronic injuries usually lack edema (Fig. 10). Heterotopic ossification along the plantar plate suggests chronic injury. Chronic injury may also result in the development of an osteophyte at the dorsum of the first metatarsal head, which can cause hallux rigidus [16]. It is important to evaluate the chondral surfaces of the first MTP joint complex to assess for the presence of a chondral injury, which may affect management [9,10,15,17–19].
to 2 weeks of playing time; and a grade 3 injury may result in up to 10–16 weeks of lost playing time [20,21]. A different five-step grading scheme is based on the degree of capsular tearing seen at arthroscopy. Grade 0 represents attenuation of the plantar plate without a tear; grade 1 is a transverse tear of b50% of the plantar plate; grade 2 is a transverse distal tear of N50%; grade 3 is an extensive transverse and/ or longitudinal tear; and grade 4 is an extensive tear with a button hole defect [17]. To our knowledge, the degree of MRI correlation with these grading schemes has not been well established, and thus, caution is advised when implementing such classification systems based on MRI findings.
4.2. Grading
4.3. Management
Different classification schemes exist for grading turf toe injury. The simplest scheme divides turf toe injuries into three grades based on clinical examination. Grade 1 injuries are essentially capsular sprains with minimal ecchymosis and focal soft tissue swelling; grade 2 injuries are partial tears with more swelling and restricted motion due to pain; and grade 3 injuries are complete tears with severe swelling, ecchymosis, and instability of the first MTP joint (Fig. 11). Grade 1 injuries usually result in little playing time loss; grade 2 injuries may result in loss of up
The first line of management of most turf toe injuries is conservative, starting with rest, ice, compression, and elevation. When returning to play, taping of the great toe is sometimes helpful for stabilization. Indications for surgical management include instability of the first MTP
Fig. 8. A 22-year-old woman with plantar plate sprain. Sagittal PDFS image (a) shows attenuation of the first MTP plantar plate (arrow), consistent with a sprain. Short-axis T1W image (b) shows indistinctness of the plantar plate (arrow). Mild marrow edema is also seen about the interphalangeal joint (a).
Fig. 9. A 23-year-old man with first interphalangeal plantar plate injury. Sagittal T1W (a) and PDFS (b) images show thickening and indistinctness of the first interphalangeal plantar plate (arrow).
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Fig. 12. An 18-year-old man with FHB strain. Short-axis PDFS image shows hyperintensity at the myotendinous junctions of the medial and lateral heads of the FHB (arrows), consistent with muscle strains. A small amount of fluid is seen in the FHL tendon sheath (arrowhead).
joint, diastasis of a sesamoid fracture or of a bipartite sesamoid, sesamoid retraction, traumatic hallux valgus, a loose body in the joint space, a chondral injury, or if conservative management has failed [3,21]. 4.4. Incidence Fig. 10. A 63-year-old man with old plantar plate injury. Sagittal T1W (a) and STIR (b) images show thickening and indistinctness of the lateral aspect of the plantar plate, consistent with plantar plate sprain (arrow). The absence of significant soft tissue edema suggests an old injury.
Fig. 11. Schematic depicting the clinical grades of turf toe injury. Grade 1 injuries involve capsular sprains, grade 2 injuries involve partial tearing of the plantar plate and joint capsule structures, and grade 3 injuries involve frank capsular tears.
The incidence of turf toe injuries among collegiate football players was initially believed to be five to six injuries per team per season;
Fig. 13. A 28-year-old woman with lateral hallux sesamoid fracture. AP (a) and axial sesamoid (b) radiographs of the right first toe show a linear fracture of the lateral hallux sesamoid, oriented in a parasagittal plane, in contrast to the typical transverse orientation of a bipartite sesamoid.
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4.5. Other associated injuries Besides plantar plate injury, the metatarsal–sesamoidal, sesamoid– phalangeal, dorsal joint capsule, and medial and lateral collateral ligaments are also susceptible to injury, depending on the mechanism of trauma. Extreme plantarflexion of the first MTP joint is known to occur among beach volleyball players, and the resulting injury to the dorsal joint capsule has been called “sand toe” [25]. Alternatively, hyperdorsiflexion injury of the MTP joint can also sometimes result in dorsal extensor expansion injury, as described in skimboarders [26]. As the sesamoids are embedded within the FHB muscle bellies, FHB strains can also be seen as a feature of turf toe injury and are detected at MRI by the presence of feathery edema about the musculotendinous junction (Fig. 12). Sesamoid fractures or contusions may also occur but may occasionally be difficult to differentiate from bipartite sesamoids. Comparison with the contralateral side and attention to the orientation of the linear lucency (partitions are transversely oriented, but fractures are not necessarily so), width of the partition, and the presence or absence of edema can be used to help differentiate between a fracture, diastasis, and a normal partition (Figs. 13–14). Bipartite sesamoids will also have corticated margins with rounding of the edges at the partition, whereas acute fractures will have matched noncorticated margins. Stress fractures of the sesamoids may be radiographically occult or may show subtle linear sclerosis. MRI examination will typically show a low signal line on T1W images, and adjacent edema may be present (Fig. 15). 5. Sesamoid disorders
Fig. 14. A 19-year-old male football player with lateral sesamoid fracture. Oblique radiograph (a) and short-axis (b), sagittal (c), and long-axis (d) CT images with bone windows show a comminuted fracture of the lateral hallux sesamoid.
however, more recent studies estimate a lower incidence of turf toe injuries of 0.46 to 0.53 injury per team per season [14,22,23]. It is not clear whether the discrepancy in these statistics reflects errors in measurement or advances in artificial turf and athletic cleats. One recent study found first MTP joint/turf toe injuries to be third most common among all foot and ankle injuries at the collegiate football level, following lateral ankle and syndesmotic sprains [24]. Turf toe is also common among professional football players, and it is estimated that 45% of players will experience a turf toe injury at least once in their careers [20]. Although thought of as a football related injury, turf toe is also known to occur among soccer and basketball players [16].
Sesamoid disorders comprise about 9% of all foot and ankle injuries and 1.2% of running injuries [1]. The hallux sesamoids are susceptible to a range of chronic pathologic processes that typically present with symptoms of pain. Sesamoiditis typically affects young adults, and etiologies include chronic repetitive stress, chondrosis and degenerative joint disease, and avascular necrosis (AVN, osteonecrosis). One or a combination of a few separate etiologies may be involved, but regardless of cause, the clinical picture is often described as “sesamoiditis.” The medial hallux sesamoid is more commonly affected than the lateral. Anatomic variations such as pes cavus, persistently plantarflexed first ray, ankle equinus, absence of a metatarsal crista, abnormal rotation of a sesamoid, and abnormal sesamoid size have been implicated as predisposing factors [1,2,27]. 5.1. Imaging findings It is sometimes challenging to differentiate between the causes of sesamoid pain at the time of imaging. Stress-related changes may
Fig. 15. A 44-year-old man with medial hallux stress fracture. Axial sesamoid radiograph (a) shows a subtle line of sclerosis. Short-axis T1W (b) and PDFS (c) images show a low signal line (arrow) and edema (arrowhead) within the medial sesamoid. Mild fibrosis is seen in the plantar soft tissues (asterisk), consistent with pressure-related change.
Please cite this article as: Schein AJ, et al, Turf toe and sesamoiditis: what the radiologist needs to know, Clin Imaging (2014), http://dx.doi.org/ 10.1016/j.clinimag.2014.11.011
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Fig. 16. A 32-year-old woman with lateral hallux sesamoid AVN. Short-axis T1W (a) and STIR (b) images show sclerosis and fragmentation of the lateral hallux sesamoid (arrow). Sagittal STIR image through the sclerotic lateral hallux sesamoid (c) shows a small first MTP joint effusion (arrow).
have a varied appearance depending on the degree of acuity. Sesamoid stress fractures tend to affect young female athletes and almost always involve the medial hallux sesamoid (Fig. 15) [28]. Acute stress-related changes may produce edema on PDFS or STIR MRI sequences. In later stages, sclerosis may be present at radiography or CT. The appearance of AVN and stress-related changes are similar, and AVN indeed may result from chronic stress or old injury. Contrast-enhanced MRI may be
useful in making the distinction between stress injury and AVN. In late stages, bony fragmentation and sclerosis may be present (Fig. 16). In cases of chondrosis, subchondral marrow edema or cystic change will typically be seen in the sesamoid or the metatarsal head on PDFS or STIR MRI sequences. Subchondral sclerosis may appear on MRI as low signal lines or patches. Partial- or full-thickness chondral defects may be detected on T1W, PD, or PDFS sequences (Fig. 17). Joint space loss and osteophytes may be present in more advanced cases. MTP joint effusion, adventitial bursa formation, or FHL tenosynovitis are not uncommon features of sesamoiditis [11]. Despite the presence or absence of findings at radiography, CT, or MRI, confident localization of the patient’s symptoms to the hallux sesamoids may remain elusive. Technetium-99m methylene diphosphonate bone scan is sometimes useful to confirm that the pathology localizes to the hallux sesamoids, but may generate a false-negative result in subtle cases [1,6,29]. 5.2. Management The first-line treatment of sesamoiditis is conservative management, consisting of immobilization with spica cast or boot in acute cases, management of weight bearing with orthotics, and nonsteroidal antiinflammatory drugs. Injection of corticosteroids is usually inappropriate but may be considered in specific cases. Repeated corticosteroid injections are not advised [6,29]. Surgical management of sesamoiditis was described as early as 1914 [30]. Techniques have varied over the years, and isolated medial or lateral partial or complete sesamoidectomy is now the preferred technique [1]. Once the patient’s pain is confidently determined to localize to the sesamoid, complete or partial sesamoidectomy can provide pain relief and restore lost function (Figs. 18–19). While significant postoperative morbidity was once common, recent studies show improved results [6,29,31]. Recently, an excellent outcome was shown following partial sesamoid resection after an acute stress fracture [28]. Surgical management is not without risk, of course. Complete sesamoidectomy has been shown to reduce push-off strength of the first toe. This can result in inability to stand tiptoe or can lead to a cock-up deformity. Partial sesamoid resection, however, does not appear to affect the mechanics of the first MTP joint [5,6,32]. Hallux valgus or varus may occur, and changes in weight bearing can lead to transfer metatarsalgia. 5.3. Other conditions involving the hallux sesamoids
Fig. 17. A 34-year-old man with medial hallux chondrosis. Short-axis T1W (a) and PDFS (b) images show subchondral edema at the medial metatarsal–sesamoidal facet and medial hallux sesamoid (arrowheads).
The first MTP joint complex is also susceptible to osteoarthritis, rheumatoid arthritis and seronegative inflammatory arthritides, gout and other crystal deposition diseases, septic arthritis, and osteomyelitis. Osteoarthritis may affect the metatarsal–sesamoidal or MTP joints, and in particular a dorsal osteophyte at the metatarsal head may cause
Please cite this article as: Schein AJ, et al, Turf toe and sesamoiditis: what the radiologist needs to know, Clin Imaging (2014), http://dx.doi.org/ 10.1016/j.clinimag.2014.11.011
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Fig. 18. A 41-year-old woman with lateral hallux sesamoiditis and subsequent resection. Axial sesamoid radiograph (a) shows comminuted fracture and sclerosis of the lateral hallux sesamoid. Delayed-phase bone scan (b) shows increased technetium-99m methylene diphosphonate uptake in the region of the lateral hallux sesamoid (arrow), midfoot, and first distal phalanx. Overlay of foot bones edges (c) better demonstrates localization to lateral hallux sesamoid. Blood flow and soft tissue phases (not shown) also showed increased uptake. The lateral hallux sesamoid was subsequently resected with resolution of the patient’s symptoms.
hallux rigidus. Subchondral cysts can form, and large geodes are sometimes encountered (Fig. 20). Gouty tophi can cause periarticular erosions and bursitis. Inflammatory arthritides may cause intra-articular erosions beginning at the joint margins. Tenosynovitis is also a common feature of inflammatory arthritis, and differentiation among the inflammatory arthritides is made easier by comparison with radiographs and review of the clinical history. Diabetes mellitus is a common predisposing factor for septic arthritis and osteomyelitis, but it may also occur as a result of trauma or other systemic illness. Osteomyelitis usually appears as patchy areas of decreased T1W signal and corresponding increased fluid-sensitive signal with or without bone erosions, in direct contiguity with skin and soft tissue ulcers, sinus tracts, cellulitis, phlegmonous collections/abscesses, or soft tissue gas (Fig. 21) [2,11]. 6. Conclusion The first MTP joint has complex anatomy that is critical for proper biomechanics. Imaging, particularly MRI, plays a crucial role in
Fig. 19. An 18-year-old man with sesamoiditis of a bipartite medial hallux sesamoid. AP radiograph (a) shows a bipartite medial hallux sesamoid, with slight distraction of the fragments (arrow). Long-axis T1W (b) and STIR (c) images show marrow edema and fluid within the synchondrosis (arrows).
diagnosing plantar plate and other “turf toe” injuries and for the heterogeneous group of disorders affecting the hallux sesamoids, often referred to clinically as “sesamoiditis.” With knowledge of this first MTP joint anatomy and the array of pathology that can affect this joint complex, the radiologist can help the referring clinician or orthopedist determine appropriate management and treatment to minimize morbidity and facilitate faster recovery and rehabilitation.
Conflict of interest The authors declare that they have no conflict of interest.
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Fig. 20. A 60-year-old woman with degenerative joint disease of the medial and lateral metatarsal–sesamoidal joints. Sagittal T1W (a) and STIR (b), and short-axis T1W (c) and STIR (d) images show a bipartite medial hallux sesamoid (thin arrow), spurring of the first metatarsal head (thick arrows), subchondral cysts in the metatarsal head and lateral sesamoid (arrowheads), and stress-related edema (asterisks). [20] McCormick JJ, Anderson RB. Turf toe: anatomy, diagnosis, and treatment. Sports Health 2010;2(6):487–94. [21] McCormick JJ, Anderson RB. Rehabilitation following turf toe injury and plantar plate repair. Clin Sports Med 2010;29(2):313–23 [ix]. [22] Coker TP, Arnold JA, Weber DL. Traumatic lesions of the metatarsophalangeal joint of the great toe in athletes. Am J Sports Med 1978;6(6):326–34. [23] George E, Harris AH, Dragoo JL, Hunt KJ. Incidence and risk factors for turf toe injuries in intercollegiate football: data from the national collegiate athletic association injury surveillance system. Foot Ankle Int 2014;35(2):108–15. [24] Kaplan LD, Jost PW, Honkamp N, Norwig J, West R, Bradley JP. Incidence and variance of foot and ankle injuries in elite college football players. Am J Orthop 2011; 40(1):40–4. [25] Frey C, Andersen GD, Feder KS. Plantarflexion injury to the metatarsophalangeal joint ("sand toe"). Foot Ankle Int 1996;17(9):576–81.
[26] Donnelly LF, Betts JB, Fricke BL. Skimboarder's toe: findings on high-field MRI. AJR Am J Roentgenol 2005;184(5):1481–5. [27] Taylor JA, Sartoris DJ, Huang GS, Resnick DL. Painful conditions affecting the first metatarsal sesamoid bones. Radiographics 1993;13(4):817–30. [28] Biedert R, Hintermann B. Stress fractures of the medial great toe sesamoids in athletes. Foot Ankle Int 2003;24(2):137–41. [29] Lee S, James WC, Cohen BE, Davis WH, Anderson RB. Evaluation of hallux alignment and functional outcome after isolated tibial sesamoidectomy. Foot Ankle Int 2005;26 (10):803–9. [30] Speed K. Injuries of the great toe sesamoids. Ann Surg 1914;60(4):478–80. [31] Mann RA, Coughlin MJ. Hallux valgus—etiology, anatomy, treatment and surgical considerations. Clin Orthop Relat Res 1981;157:31–41. [32] Aper RL, Saltzman CL, Brown TD. The effect of hallux sesamoid excision on the flexor hallucis longus moment arm. Clin Orthop Relat Res 1996;325:209–17.
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Fig. 21. A 51-year-old man with osteomyelitis of the first metatarsal and lateral hallux sesamoid. Short-axis T1W (a) and STIR (b) images show edema and marrow replacement within the lateral hallux sesamoid and first metatarsal head (arrowheads). The intersesamoid ligament is torn, and the sesamoid is laterally subluxed (thick arrow). Soft tissue edema is seen dorsally (asterisk), and there is a bubble of plantar soft tissue gas (thin arrow). A contiguous slice (c, d) shows a plantar ulcer (arrows).
Please cite this article as: Schein AJ, et al, Turf toe and sesamoiditis: what the radiologist needs to know, Clin Imaging (2014), http://dx.doi.org/ 10.1016/j.clinimag.2014.11.011
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Clinical Imaging journal homepage: http://www.clinicalimaging.org
Turf toe and sesamoiditis: what the radiologist needs to know☆,☆☆ Aaron J. Schein a, Matthew R. Skalski b, Dakshesh B. Patel a, Eric A. White a, Ryan Lundquist c, Christopher J. Gottsegen d, Deborah M. Forrester a, George R. Matcuk Jr. a,⁎ a
Department of Radiology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033-5313 Department of Radiology, Southern California University of Health Sciences, Whittier, CA 90604 Radiology and Imaging Consultants, Colorado Springs, CO 80903 d Department of Radiology, New York University, Langone Medical Center, New York, NY 10016 b c
a r t i c l e
i n f o
Article history: Received 13 September 2014 Received in revised form 8 November 2014 Accepted 11 November 2014 Available online xxxx Keywords: Turf toe Sesamoiditis First metatarsophalangeal joint complex Plantar plate
a b s t r a c t The first metatarsophalangeal (MTP) joint complex is a critical weight-bearing structure important to biomechanics. An acute dorsiflexion injury, named “turf toe,” is common among American football and soccer players. “Sesamoiditis” is a name often given for pain arising from the hallux sesamoids in the absence of acute trauma, and may result from a variety of causes. The first MTP joint complex can also be affected by degenerative or inflammatory arthritis, infarct, and infection. This review article will cover the anatomy and biomechanics of the first MTP joint complex, its patterns of injury and pathology, imaging techniques, and management. © 2014 Elsevier Inc. All rights reserved.
1. Introduction The first metatarsophalangeal (MTP) joint and its associated capsular complex are a critical weight-bearing structure important in the biomechanics of standing, running, and gait. The first MTP complex is particularly susceptible to injury among collegiate and professional American football and soccer players (commonly known as “turf toe”) but, like most other joints, is also affected by a broad range of pathology including stress and overuse, degenerative and inflammatory arthritis, infarct, and infection. Unaddressed pathology can lead to long-term morbidity and loss of function, and conservative and surgical methods have been used to effectively treat many of these disorders. The first MTP complex is made up of several small osseous, ligamentous, and musculotendinous structures, but its anatomic complexity is easily simplified by understanding its essential biomechanics. This review will cover the anatomy and biomechanics of the first MTP complex, essential imaging tools, the spectrum of injury and pathology, and current treatment methods. 2. Anatomy and biomechanics Sesamoids were first named by Galen around 180 CE due to the tiny bones’ resemblance to sesame seeds [1]. Sesamoids are small bones that ☆ Grants received: none. ☆☆ Disclosures: none. ⁎ Corresponding author. Department of Radiology, Keck School of Medicine, University of Southern California, 1500 San Pablo Street, 2nd Floor Imaging, Los Angeles, CA 900335313. Tel.: +1 323 442 8721; fax: +1 323 442 8755. E-mail address: [email protected] (G.R. Matcuk).
form entirely within tendons as they curve around joints. They may form within a joint capsule (e.g., the hallux sesamoids and patella), or they may be separated from the apposing bone by a synovial-lined bursa (e.g., the peroneus longus sesamoid). In either case, the articulating surfaces of the sesamoid and the apposing bone are lined by hyaline cartilage [2]. The hallux sesamoids typically ossify by 9–11 years of age [3]. The two hallux sesamoids arise within the paired flexor hallucis brevis (FHB) tendons (medial and lateral heads). Typically, the medial hallux sesamoid is slightly more distal than the lateral. The sesamoids sit on the plantar surface of the forefoot, directly underlying the first metatarsal head. There is a bony ridge on the undersurface of the first metatarsal head called the crista that separates the sesamoids, delineating the medial and lateral metatarsal–sesamoidal joints (Fig. 1) [4]. The medial hallux sesamoid is frequently bipartite, and the lateral sesamoid is occasionally so (Fig. 2) The hallux sesamoids elevate the first metatarsal head, providing a moment arm that augments plantar flexion of the first MTP joint [5–8]. The hallux sesamoids are inextricable from the first MTP joint capsule. A dense fibrous band deep to the flexor hallucis longus (FHL) tendon called the plantar plate connects the hallux sesamoids and the plantar base of the first proximal phalanx, forming the plantar aspect of the first MTP joint capsule (Fig. 3) [4]. The sesamoids act as a pulley to transmit force from the FHB muscles to the base of the first proximal phalanx, through the plantar plate [6–8]. An analogous plantar plate is found at the proximal base of every phalanx in the foot. The sesamoids are further anchored to the first metatarsal head and base of the proximal phalanx by the medial and lateral metatarsal–sesamoidal and sesamoidal–phalangeal ligaments, contributing along with the collateral ligaments to the medial and lateral aspects of the first MTP joint
http://dx.doi.org/10.1016/j.clinimag.2014.11.011 0899-7071/© 2014 Elsevier Inc. All rights reserved.
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Fig. 1. Normal bony anatomy of the first MTP joint.
capsule [4]. The abductor and adductor hallucis tendons insert on the medial and lateral bases of the first proximal phalanx, respectively, and also give off small attachments to the sesamoids [1]. A small fibrous band called the intersesamoid ligament connects the medial and lateral hallux sesamoids (Fig. 4). The forces of weight bearing are distributed to the first metatarsal head by the various sesamoid ligaments and the action of the diarthrodial metatarsal–sesamoidal joints [6–8].
3. Imaging techniques Radiographic evaluation of the hallux sesamoids is performed with a combination of anterior–posterior (AP), oblique, and lateral projections. Coronal imaging of the hallux sesamoids can be helpful for profiling the metatarsal–sesamoidal joints [2]. A lateral view stress test with 45° of MTP dorsiflexion may also be performed to assess the functional integrity of the plantar plate [9]. Computed tomography (CT) may be helpful in assessing fractures, sclerosis, or bony erosion. Evaluation of the soft tissue structures, however, is best performed using magnetic resonance imaging (MRI).
Fig. 3. Normal muscles, ligaments, and tendons of the first MTP joint.
Since the first MTP joint complex is a small structure and the individual components that must be scrutinized are smaller still, strict attention to MRI parameters is advised to optimize the sensitivity and specificity of the examination. An extremity surface coil placed over the forefoot will help to improve signal to noise ratio, and an appropriately small field of view will increase spatial resolution. Imaging at 3-T field strength provides optimal signal to noise ratio, but imaging at 1.5-T field strength is adequate and more readily available. Imaging parameters vary from institution to institution, but ideally, the field of view should be between 10 and 14 cm, slice thickness should be 3 mm, and there should be an interslice gap of 0.3 mm (10%) [10]. A thorough examination includes non-fat-suppressed T1-weighted (T1W) or proton density (PD) images in conjunction with fluidsensitive fat-suppressed PD (PDFS) or short tau inversion recovery (STIR) images, performed in coronal (short axis of foot), axial (long
Fig. 2. Oblique views of normal bipartite medial (a) and lateral (b) hallux sesamoids in different patients.
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players. It was described as a hyperextension (dorsiflexion) injury to the first MTP complex and was felt to result from the combination of flexible sole cleats being used on hard, artificial turf. Turf toe results from axial loading forces applied to the forefoot while the first MTP joint is in the equinovarus (tiptoe) position (Fig. 5) [14]. Injuries occur along a spectrum of severity from low-grade capsular sprains to highgrade capsular and ligamentous tears, and may be complicated by MTP joint malalignment (usually in the form of hallux valgus), subluxation, and sesamoid fractures. Although much emphasis is given to turf toe, chronic degenerative disease can also lead to plantar plate injury. 4.1. MRI findings
Fig. 4. Short-axis T1W image through the first metatarsal head, showing normal anatomy.
axis of foot), and parasagittal planes. Both non-fat-suppressed T1W and PD sequences are well suited for visualizing ligaments and tendons, but T1W sequences provide an accurate map of normal marrow fat, while PD images provide superior imaging of the chondral surfaces. Fluidsensitive PDFS and STIR images are sensitive to edema and help to demonstrate acute traumatic, degenerative, or inflammatory changes. PDFS images take less time to acquire and have better signal to noise ratio than STIR, but homogeneous fat suppression is easier to achieve with STIR. Thus, STIR is preferred in situations where homogeneous fat suppression is difficult to achieve, such as in postoperative patients with micrometallic debris in the surgical bed. Routine intravenous contrast is not necessary, but it is helpful in the evaluation of tumor or infection [10,11]. Toe traction and MR arthrography may offer an improved assessment in some cases [12,13].
MRI is a useful and accurate tool for evaluating plantar plate injuries. The normal plantar plate appears as a dense band of low signal connecting the hallux sesamoids (or the metatarsal head in the case of the lesser metatarsals) to the plantar base of the proximal phalanx and is seen best on sagittal and short-axis images (Fig. 6). MRI findings in plantar plate injury vary with the severity and acuity of the injury. Full-thickness plantar plate tears will appear as focal discontinuity of the plantar plate with retraction and a fluid gap (Fig. 7), whereas sprains and partial thickness tears may show either thinning or thickening with indistinctness of the plantar plate (Figs. 8–9). However, care must be taken not to overcall partial tears, as plantar plate recesses can be seen
4. Turf toe and associated injuries Turf toe was first described by Bowers and Martin in 1976 as a plantar capsular sprain of the first MTP joint in collegiate American football
Fig. 5. Illustration of the mechanism of a turf toe injury. Axial loading forces are applied to the first MTP joint while in the equinovarus position.
Fig. 6. Sagittal T1W and PDFS images of the first MTP plantar plate (a), second MTP plantar plate (b), and interphalangeal plantar plates (c).
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Fig. 7. An 18-year-old man with acute plantar plate tear. Sagittal PDFS (a) and T1W (b), and short-axis STIR (c) images show disruption of the first MTP plantar plate (arrows) and retraction of the medial hallux sesamoid (arrowheads), with associated edema. Normal FHL tendon (asterisk).
at the proximal phalangeal attachment as a normal variant [15]. Proximal retraction of the sesamoids is expected in cases of complete plantar plate tear and may be detected with lateral radiographs with the great toe stressed in dorsiflexion [9]. Acute injuries will usually demonstrate associated soft tissue edema, while chronic injuries usually lack edema (Fig. 10). Heterotopic ossification along the plantar plate suggests chronic injury. Chronic injury may also result in the development of an osteophyte at the dorsum of the first metatarsal head, which can cause hallux rigidus [16]. It is important to evaluate the chondral surfaces of the first MTP joint complex to assess for the presence of a chondral injury, which may affect management [9,10,15,17–19].
to 2 weeks of playing time; and a grade 3 injury may result in up to 10–16 weeks of lost playing time [20,21]. A different five-step grading scheme is based on the degree of capsular tearing seen at arthroscopy. Grade 0 represents attenuation of the plantar plate without a tear; grade 1 is a transverse tear of b50% of the plantar plate; grade 2 is a transverse distal tear of N50%; grade 3 is an extensive transverse and/ or longitudinal tear; and grade 4 is an extensive tear with a button hole defect [17]. To our knowledge, the degree of MRI correlation with these grading schemes has not been well established, and thus, caution is advised when implementing such classification systems based on MRI findings.
4.2. Grading
4.3. Management
Different classification schemes exist for grading turf toe injury. The simplest scheme divides turf toe injuries into three grades based on clinical examination. Grade 1 injuries are essentially capsular sprains with minimal ecchymosis and focal soft tissue swelling; grade 2 injuries are partial tears with more swelling and restricted motion due to pain; and grade 3 injuries are complete tears with severe swelling, ecchymosis, and instability of the first MTP joint (Fig. 11). Grade 1 injuries usually result in little playing time loss; grade 2 injuries may result in loss of up
The first line of management of most turf toe injuries is conservative, starting with rest, ice, compression, and elevation. When returning to play, taping of the great toe is sometimes helpful for stabilization. Indications for surgical management include instability of the first MTP
Fig. 8. A 22-year-old woman with plantar plate sprain. Sagittal PDFS image (a) shows attenuation of the first MTP plantar plate (arrow), consistent with a sprain. Short-axis T1W image (b) shows indistinctness of the plantar plate (arrow). Mild marrow edema is also seen about the interphalangeal joint (a).
Fig. 9. A 23-year-old man with first interphalangeal plantar plate injury. Sagittal T1W (a) and PDFS (b) images show thickening and indistinctness of the first interphalangeal plantar plate (arrow).
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Fig. 12. An 18-year-old man with FHB strain. Short-axis PDFS image shows hyperintensity at the myotendinous junctions of the medial and lateral heads of the FHB (arrows), consistent with muscle strains. A small amount of fluid is seen in the FHL tendon sheath (arrowhead).
joint, diastasis of a sesamoid fracture or of a bipartite sesamoid, sesamoid retraction, traumatic hallux valgus, a loose body in the joint space, a chondral injury, or if conservative management has failed [3,21]. 4.4. Incidence Fig. 10. A 63-year-old man with old plantar plate injury. Sagittal T1W (a) and STIR (b) images show thickening and indistinctness of the lateral aspect of the plantar plate, consistent with plantar plate sprain (arrow). The absence of significant soft tissue edema suggests an old injury.
Fig. 11. Schematic depicting the clinical grades of turf toe injury. Grade 1 injuries involve capsular sprains, grade 2 injuries involve partial tearing of the plantar plate and joint capsule structures, and grade 3 injuries involve frank capsular tears.
The incidence of turf toe injuries among collegiate football players was initially believed to be five to six injuries per team per season;
Fig. 13. A 28-year-old woman with lateral hallux sesamoid fracture. AP (a) and axial sesamoid (b) radiographs of the right first toe show a linear fracture of the lateral hallux sesamoid, oriented in a parasagittal plane, in contrast to the typical transverse orientation of a bipartite sesamoid.
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4.5. Other associated injuries Besides plantar plate injury, the metatarsal–sesamoidal, sesamoid– phalangeal, dorsal joint capsule, and medial and lateral collateral ligaments are also susceptible to injury, depending on the mechanism of trauma. Extreme plantarflexion of the first MTP joint is known to occur among beach volleyball players, and the resulting injury to the dorsal joint capsule has been called “sand toe” [25]. Alternatively, hyperdorsiflexion injury of the MTP joint can also sometimes result in dorsal extensor expansion injury, as described in skimboarders [26]. As the sesamoids are embedded within the FHB muscle bellies, FHB strains can also be seen as a feature of turf toe injury and are detected at MRI by the presence of feathery edema about the musculotendinous junction (Fig. 12). Sesamoid fractures or contusions may also occur but may occasionally be difficult to differentiate from bipartite sesamoids. Comparison with the contralateral side and attention to the orientation of the linear lucency (partitions are transversely oriented, but fractures are not necessarily so), width of the partition, and the presence or absence of edema can be used to help differentiate between a fracture, diastasis, and a normal partition (Figs. 13–14). Bipartite sesamoids will also have corticated margins with rounding of the edges at the partition, whereas acute fractures will have matched noncorticated margins. Stress fractures of the sesamoids may be radiographically occult or may show subtle linear sclerosis. MRI examination will typically show a low signal line on T1W images, and adjacent edema may be present (Fig. 15). 5. Sesamoid disorders
Fig. 14. A 19-year-old male football player with lateral sesamoid fracture. Oblique radiograph (a) and short-axis (b), sagittal (c), and long-axis (d) CT images with bone windows show a comminuted fracture of the lateral hallux sesamoid.
however, more recent studies estimate a lower incidence of turf toe injuries of 0.46 to 0.53 injury per team per season [14,22,23]. It is not clear whether the discrepancy in these statistics reflects errors in measurement or advances in artificial turf and athletic cleats. One recent study found first MTP joint/turf toe injuries to be third most common among all foot and ankle injuries at the collegiate football level, following lateral ankle and syndesmotic sprains [24]. Turf toe is also common among professional football players, and it is estimated that 45% of players will experience a turf toe injury at least once in their careers [20]. Although thought of as a football related injury, turf toe is also known to occur among soccer and basketball players [16].
Sesamoid disorders comprise about 9% of all foot and ankle injuries and 1.2% of running injuries [1]. The hallux sesamoids are susceptible to a range of chronic pathologic processes that typically present with symptoms of pain. Sesamoiditis typically affects young adults, and etiologies include chronic repetitive stress, chondrosis and degenerative joint disease, and avascular necrosis (AVN, osteonecrosis). One or a combination of a few separate etiologies may be involved, but regardless of cause, the clinical picture is often described as “sesamoiditis.” The medial hallux sesamoid is more commonly affected than the lateral. Anatomic variations such as pes cavus, persistently plantarflexed first ray, ankle equinus, absence of a metatarsal crista, abnormal rotation of a sesamoid, and abnormal sesamoid size have been implicated as predisposing factors [1,2,27]. 5.1. Imaging findings It is sometimes challenging to differentiate between the causes of sesamoid pain at the time of imaging. Stress-related changes may
Fig. 15. A 44-year-old man with medial hallux stress fracture. Axial sesamoid radiograph (a) shows a subtle line of sclerosis. Short-axis T1W (b) and PDFS (c) images show a low signal line (arrow) and edema (arrowhead) within the medial sesamoid. Mild fibrosis is seen in the plantar soft tissues (asterisk), consistent with pressure-related change.
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Fig. 16. A 32-year-old woman with lateral hallux sesamoid AVN. Short-axis T1W (a) and STIR (b) images show sclerosis and fragmentation of the lateral hallux sesamoid (arrow). Sagittal STIR image through the sclerotic lateral hallux sesamoid (c) shows a small first MTP joint effusion (arrow).
have a varied appearance depending on the degree of acuity. Sesamoid stress fractures tend to affect young female athletes and almost always involve the medial hallux sesamoid (Fig. 15) [28]. Acute stress-related changes may produce edema on PDFS or STIR MRI sequences. In later stages, sclerosis may be present at radiography or CT. The appearance of AVN and stress-related changes are similar, and AVN indeed may result from chronic stress or old injury. Contrast-enhanced MRI may be
useful in making the distinction between stress injury and AVN. In late stages, bony fragmentation and sclerosis may be present (Fig. 16). In cases of chondrosis, subchondral marrow edema or cystic change will typically be seen in the sesamoid or the metatarsal head on PDFS or STIR MRI sequences. Subchondral sclerosis may appear on MRI as low signal lines or patches. Partial- or full-thickness chondral defects may be detected on T1W, PD, or PDFS sequences (Fig. 17). Joint space loss and osteophytes may be present in more advanced cases. MTP joint effusion, adventitial bursa formation, or FHL tenosynovitis are not uncommon features of sesamoiditis [11]. Despite the presence or absence of findings at radiography, CT, or MRI, confident localization of the patient’s symptoms to the hallux sesamoids may remain elusive. Technetium-99m methylene diphosphonate bone scan is sometimes useful to confirm that the pathology localizes to the hallux sesamoids, but may generate a false-negative result in subtle cases [1,6,29]. 5.2. Management The first-line treatment of sesamoiditis is conservative management, consisting of immobilization with spica cast or boot in acute cases, management of weight bearing with orthotics, and nonsteroidal antiinflammatory drugs. Injection of corticosteroids is usually inappropriate but may be considered in specific cases. Repeated corticosteroid injections are not advised [6,29]. Surgical management of sesamoiditis was described as early as 1914 [30]. Techniques have varied over the years, and isolated medial or lateral partial or complete sesamoidectomy is now the preferred technique [1]. Once the patient’s pain is confidently determined to localize to the sesamoid, complete or partial sesamoidectomy can provide pain relief and restore lost function (Figs. 18–19). While significant postoperative morbidity was once common, recent studies show improved results [6,29,31]. Recently, an excellent outcome was shown following partial sesamoid resection after an acute stress fracture [28]. Surgical management is not without risk, of course. Complete sesamoidectomy has been shown to reduce push-off strength of the first toe. This can result in inability to stand tiptoe or can lead to a cock-up deformity. Partial sesamoid resection, however, does not appear to affect the mechanics of the first MTP joint [5,6,32]. Hallux valgus or varus may occur, and changes in weight bearing can lead to transfer metatarsalgia. 5.3. Other conditions involving the hallux sesamoids
Fig. 17. A 34-year-old man with medial hallux chondrosis. Short-axis T1W (a) and PDFS (b) images show subchondral edema at the medial metatarsal–sesamoidal facet and medial hallux sesamoid (arrowheads).
The first MTP joint complex is also susceptible to osteoarthritis, rheumatoid arthritis and seronegative inflammatory arthritides, gout and other crystal deposition diseases, septic arthritis, and osteomyelitis. Osteoarthritis may affect the metatarsal–sesamoidal or MTP joints, and in particular a dorsal osteophyte at the metatarsal head may cause
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Fig. 18. A 41-year-old woman with lateral hallux sesamoiditis and subsequent resection. Axial sesamoid radiograph (a) shows comminuted fracture and sclerosis of the lateral hallux sesamoid. Delayed-phase bone scan (b) shows increased technetium-99m methylene diphosphonate uptake in the region of the lateral hallux sesamoid (arrow), midfoot, and first distal phalanx. Overlay of foot bones edges (c) better demonstrates localization to lateral hallux sesamoid. Blood flow and soft tissue phases (not shown) also showed increased uptake. The lateral hallux sesamoid was subsequently resected with resolution of the patient’s symptoms.
hallux rigidus. Subchondral cysts can form, and large geodes are sometimes encountered (Fig. 20). Gouty tophi can cause periarticular erosions and bursitis. Inflammatory arthritides may cause intra-articular erosions beginning at the joint margins. Tenosynovitis is also a common feature of inflammatory arthritis, and differentiation among the inflammatory arthritides is made easier by comparison with radiographs and review of the clinical history. Diabetes mellitus is a common predisposing factor for septic arthritis and osteomyelitis, but it may also occur as a result of trauma or other systemic illness. Osteomyelitis usually appears as patchy areas of decreased T1W signal and corresponding increased fluid-sensitive signal with or without bone erosions, in direct contiguity with skin and soft tissue ulcers, sinus tracts, cellulitis, phlegmonous collections/abscesses, or soft tissue gas (Fig. 21) [2,11]. 6. Conclusion The first MTP joint has complex anatomy that is critical for proper biomechanics. Imaging, particularly MRI, plays a crucial role in
Fig. 19. An 18-year-old man with sesamoiditis of a bipartite medial hallux sesamoid. AP radiograph (a) shows a bipartite medial hallux sesamoid, with slight distraction of the fragments (arrow). Long-axis T1W (b) and STIR (c) images show marrow edema and fluid within the synchondrosis (arrows).
diagnosing plantar plate and other “turf toe” injuries and for the heterogeneous group of disorders affecting the hallux sesamoids, often referred to clinically as “sesamoiditis.” With knowledge of this first MTP joint anatomy and the array of pathology that can affect this joint complex, the radiologist can help the referring clinician or orthopedist determine appropriate management and treatment to minimize morbidity and facilitate faster recovery and rehabilitation.
Conflict of interest The authors declare that they have no conflict of interest.
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Please cite this article as: Schein AJ, et al, Turf toe and sesamoiditis: what the radiologist needs to know, Clin Imaging (2014), http://dx.doi.org/ 10.1016/j.clinimag.2014.11.011
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Please cite this article as: Schein AJ, et al, Turf toe and sesamoiditis: what the radiologist needs to know, Clin Imaging (2014), http://dx.doi.org/ 10.1016/j.clinimag.2014.11.011
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Fig. 21. A 51-year-old man with osteomyelitis of the first metatarsal and lateral hallux sesamoid. Short-axis T1W (a) and STIR (b) images show edema and marrow replacement within the lateral hallux sesamoid and first metatarsal head (arrowheads). The intersesamoid ligament is torn, and the sesamoid is laterally subluxed (thick arrow). Soft tissue edema is seen dorsally (asterisk), and there is a bubble of plantar soft tissue gas (thin arrow). A contiguous slice (c, d) shows a plantar ulcer (arrows).
Please cite this article as: Schein AJ, et al, Turf toe and sesamoiditis: what the radiologist needs to know, Clin Imaging (2014), http://dx.doi.org/ 10.1016/j.clinimag.2014.11.011
