Original Research
Musculoskeletal Imaging
May 2011

The Spring Ligament Recess of the Talocalcaneonavicular Joint: Depiction on MR Images With Cadaveric and Histologic Correlation

Abstract

OBJECTIVE. The objective of this study was to describe the anatomy and MR appearance of the spring ligament recess of the talocalcaneonavicular joint.
SUBJECTS AND METHODS. Forty-nine MR examinations of the ankle with a spring ligament recess were prospectively collected. The size of the recess was measured. The presence of the following variables was recorded: talocalcaneonavicular joint effusion, ankle joint effusion, talar head impaction, acute lateral ankle sprain, chronic lateral ankle sprain, spring ligament tear, sinus tarsi ligament tear, talar dome osteochondral injury, and talonavicular osteoarthrosis. The Fisher exact test was performed to quantify the association of the talocalcaneonavicular effusion with the other variables. MR arthrography and dissection with histologic analysis were performed in two cadaveric ankles.
RESULTS. Twenty-four men and 25 women (average age, 39 years; range, 21–77 years) were included in the study. The average size of the fluid collection was 0.4 × 0.8 cm (range, 0.2–0.9 × 0.4–1.5 cm). The prevalence of the measured variables was talocalcaneonavicular joint effusion, 67.3%; ankle joint effusion, 61.2%; talar head impaction, 32.7%; acute lateral ankle sprain, 28.6%; chronic lateral ankle sprain, 59.2%; spring ligament tear, 14.3%; sinus tarsi ligament tear, 12.2%; talar dome osteochondral lesion, 20.4%; and talonavicular osteoarthrosis, 18.4%. There was a higher prevalence of talar head impaction among individuals with talocalcaneonavicular joint effusion (p = 0.0522). Cadaveric study revealed communication between the talocalcaneonavicular joint and the spring ligament recess.
CONCLUSION. The spring ligament recess is a synovium-lined, fluid-filled space that communicates with the talocalcaneonavicular joint. The recess should be distinguished from a tear of the plantar components of the spring ligament.

Introduction

The spring, or calcaneonavicular, ligament is one of the primary static stabilizers of the hindfoot. Along with the superficial fibers of the deltoid ligament, the long plantar ligament, and the plantar fascia, the spring ligament helps to maintain the medial longitudinal arch. Extending from the calcaneus to the navicular, the spring ligament forms a sling or hammock that supports the talar head. Disruption of the ligament allows the talus to plantarflex and the hindfoot to enter into valgus, leading to acquired flatfoot deformity. The functional role of the spring ligament is even more important when the posterior tibial tendon, the primary dynamic stabilizer of the longitudinal arch, fails. Therefore, surgical repair of the spring ligament has become an important adjunct to treating posterior tibial tendon abnormalities [1].
Much has been written describing the normal and pathologic MR features of the spring ligament [26]. To our knowledge, however, there has not yet been a study reporting the presence and the imaging features of the spring ligament recess, a fluid collection extending from the talocalcaneonavicular joint, interposed between the medioplantar oblique and inferoplantar longitudinal components of the spring ligament. Utilizing cadaveric dissections and MRI, we describe the anatomy and MR appearance of the spring ligament recess as well as the prevalence of associated pathologic MR findings of our patient population.
Fig. 1 Spring ligament recess. A and B, Illustrations of ankle joint in coronal (A) and axial (B) planes depict talocalcaneonavicular joint and spring ligament recess (black arrow) extending between medioplantar oblique (straight white arrow) and inferoplantar longitudinal (open arrow) of spring ligament. PTT = posterior tibial tendon, T = talus, C = calcaneus, N = navicular.

Subjects and Methods

Patient Population

Institutional review board approval was obtained. This study is compliant with HIPAA regulations. Forty-nine ankle MRI examinations performed at our institution from December 2008 through December 2009 that showed the presence of a spring ligament recess were prospectively collected by two authors in a consecutive fashion. Patients with a history of ankle surgery were excluded. The clinical histories in all cases were documented. Patients younger than 18 years were excluded because this study was conducted in an adult population.
Fig. 2A Spring ligament recess in 45-year-old man with history of acute trauma. Axial fast spin-echo T2 (A) and sagittal STIR (B) MR images show fluid-distended spring ligament recess (straight black arrow) extending from talocalcaneonavicular joint and interposed between medioplantar oblique fibers (straight white arrow) and inferoplantar longitudinal fibers (curved arrow, A) of spring ligament. On sagittal STIR and coronal fat-saturated proton density images (not shown), small talonavicular joint effusion was seen.
Fig. 2B Spring ligament recess in 45-year-old man with history of acute trauma. Axial fast spin-echo T2 (A) and sagittal STIR (B) MR images show fluid-distended spring ligament recess (straight black arrow) extending from talocalcaneonavicular joint and interposed between medioplantar oblique fibers (straight white arrow) and inferoplantar longitudinal fibers (curved arrow, A) of spring ligament. On sagittal STIR and coronal fat-saturated proton density images (not shown), small talonavicular joint effusion was seen.
The MR examinations were reviewed for the presence of the spring ligament recess, which was defined as a discrete, walled-off fluid collection, noted on fluid-sensitive pulse sequences in at least two orthogonal imaging planes interposed between the medioplantar oblique and inferoplantar longitudinal components of the spring ligament (Figs. 1 and 2A, 2B). The fluid collection was measured in the anterior-posterior and transverse dimensions using the axial imaging plane. The presence of communication of the fluid collection with the talocalcaneonavicular joint and the presence of a talocalcaneonavicular effusion, ankle joint effusion, talar head impaction injury, acute or chronic lateral ankle sprain, spring ligament tear, sinus tarsi ligament tear, talar osteochondral injury, and talonavicular osteoarthrosis were recorded. Statistical analysis (Fisher exact test) was performed to quantify the association of the talocalcaneonavicular effusion with these variables.

MRI Technique

The MR examinations were performed on a 1.5- or 3-T unit (Avanto or Sonata, Siemens Healthcare) utilizing the following pulse sequences: axial proton density–weighted (TR/TE, 4200/38; field of view [FOV], 110 cm); axial fat-suppressed proton density–weighted (4220/38; FOV, 110 cm); coronal fat-suppressed T2-weighted (4600/60; FOV, 140 cm); sagittal T1-weighted (700/10; FOV, 140 cm); and sagittal fat-suppressed proton density–weighted (4500/35; FOV, 140 cm). Resolution ranged from 0.4 × 0.4 × 0.3 to 0.5 × 0.5 × 3.0.

Cadaveric Study

A pair of frozen cadaveric ankles from the same man (age at death, 42 years) obtained from the hospital's orthopedics laboratory were placed out for thawing 24 hours before the fluoroscopic procedure. Under fluoroscopic guidance, 3 mL of contrast material (gadopentetate dimeglumine, Magnevist, Bayer HealthCare) was injected into the talonavicular joint of each ankle. The ankles were then placed in the MR scanner and T1-weighted images were obtained on a 1.5-T unit utilizing the following technique: TR/TE, 500/17; matrix, 512 × 512; and slice thickness, 3 mm. MR arthrographic images were reviewed for the presence of contrast material communicating between the talocalcaneonavicular joint and a focal, discrete collection located between the plantar fibers of the spring ligament (Fig. 3A, 3B, 3C). Both ankles were subsequently refrozen and cut with a band saw into 3-mm-thick slices, the first ankle in the sagittal plane and the contralateral ankle in the coronal plane. The sliced sections were photographed on both surfaces. The spring ligament recess was dissected using a scalpel sectioning the osseous attachment of the spring ligament to the calcaneus and navicular bones. The articular surface of the specimen was marked with ink. The specimen was submitted for histologic analysis of the presence of synovial lining covering the recess (Fig. 4).
Fig. 3A Communication between spring ligament recess and talocalcaneonavicular joint in cadaver specimen after intraarticular injection of gadolinium solution into talonavicular joint. Axial (A), sagittal (B), and coronal (C) T1-weighted MR images show contrast material in spring ligament recess (black arrow), between medioplantar oblique fibers (white arrow, A) and inferoplantar longitudinal fibers (curved arrow, A) of spring ligament. Communication between talocalcaneonavicular joint (asterisk, B and C) and recess is noted on sagittal and coronal images. T = talus, C = calcaneus, N = navicular.
Fig. 3B Communication between spring ligament recess and talocalcaneonavicular joint in cadaver specimen after intraarticular injection of gadolinium solution into talonavicular joint. Axial (A), sagittal (B), and coronal (C) T1-weighted MR images show contrast material in spring ligament recess (black arrow), between medioplantar oblique fibers (white arrow, A) and inferoplantar longitudinal fibers (curved arrow, A) of spring ligament. Communication between talocalcaneonavicular joint (asterisk, B and C) and recess is noted on sagittal and coronal images. T = talus, C = calcaneus, N = navicular.
Fig. 3C Communication between spring ligament recess and talocalcaneonavicular joint in cadaver specimen after intraarticular injection of gadolinium solution into talonavicular joint. Axial (A), sagittal (B), and coronal (C) T1-weighted MR images show contrast material in spring ligament recess (black arrow), between medioplantar oblique fibers (white arrow, A) and inferoplantar longitudinal fibers (curved arrow, A) of spring ligament. Communication between talocalcaneonavicular joint (asterisk, B and C) and recess is noted on sagittal and coronal images. T = talus, C = calcaneus, N = navicular.
Fig. 4 Spring ligament recess: anatomic-histologic correlation. Photograph shows sagittal 3-mm-thickness slice of cadaveric ankle. Spring ligament recess (black arrow) is seen between medioplantar oblique (white arrow) and inferoplantar longitudinal (curved arrow) of spring ligament. Histologic image of lining of spring ligament recess shows interrupted layer of synovial cells (arrow) in continuity with lining of talocalcaneonavicular joint. T = talus, C = calcaneus, N = navicular.

Results

Twenty-four men (49%) and 25 women (51%) with an average age of 39 years (range, 21–77 years) were included in the study group. Presenting clinical history included ankle pain (n = 23), acute trauma (n = 17), tendon tears (n = 5), talar osteochondral lesion (n = 1), ankle joint infection (n = 1), cellulitis (n = 1), and distal tibial enchondroma (n = 1).
The average size of the fluid collection was 0.4 × 0.8 cm (transverse and craniocaudal) (range, 0.2–0.9 × 0.4–1.5 cm). The following MR findings were noted: 67.3% of subjects (33/49) had a talocalcaneonavicular joint effusion; 61.2% (30/49), an ankle joint effusion; 32.7% (16/49), a talar head impaction injury (Fig. 5A, 5B); 28.6% (14/49), an acute lateral ankle sprain (Fig. 6A, 6B); 59.2% (29/49), a chronic lateral ankle sprain; 14.3% (7/49), a spring ligament tear; 12.2% (6/49), a sinus tarsi ligament tear; 20.4% (11/49), a talar dome osteochondral lesion; and 18.4% (9/49), talonavicular osteoarthrosis (Fig. 7A, 7B). The Fisher exact test revealed a trend toward a higher prevalence of talar head impaction among patients with talocalcaneonavicular joint effusion than among those without it (p = 0.0522). There was no statistical indication that talocalcaneonavicular joint effusion was associated with any other finding (Table 1).
TABLE 1: MR Findings Evaluated for Association With Talocalcaneonavicular Joint Effusion in 49 Study Patients
% of Cases Associated With Talocalcaneonavicular Joint Effusion (No. of Cases/Total No.)
FindingAbsentPresentp
Ankle joint effusion56.3 (9/16)63.6 (21/33)0.7565
Anterior subtalar joint effusion50.0 (8/16)53.1 (17/32)1.0000
Lateral ankle sprain   
    Acute31.3 (5/16)27.3 (9/33)1.0000
    Chronic50.0 (8/16)63.6 (21/33)0.5362
Sinus tarsi ligament tear0.0 (0/16)18.2 (6/33)0.1588
Spring ligament tear6.3 (1/16)18.2 (6/33)0.4017
Talar dome osteochondral injury12.5 (2/16)24.2 (8/33)0.4636
Talar head impaction12.5 (2/16)42.4 (14/33)0.0522
Talonavicular osteoarthritis
6.3 (1/16)
24.2 (8/33)
0.2385

Cadaveric Study

The MR images obtained in both cadaveric ankles showed a contrast-filled, well-defined space interposed between the medioplantar oblique and inferoplantar longitudinal components of the spring ligament and communicating with the talocalcaneonavicular joint. Histologic analysis revealed a layer of synovial cells covering the dorsal side of the spring ligament recess in continuity with the talocalcaneonavicular joint (Fig. 4).

Discussion

The spring ligament is composed of three distinct components: the superomedial, medioplantar oblique, and inferoplantar longitudinal bands. The largest component, the superomedial band, originates from the sustentaculum tali and inserts on the superomedial aspect of the navicular tuberosity and the tibiospring component of the deltoid ligament. The inferoplantar longitudinal component arises from the coronoid fossa, between the middle and anterior calcaneal facets, and inserts on the navicular beak. The third component, more recently described, was aptly named the “third ligament” [7]. Originally thought to be part of the inferior band, this component, since renamed the “medioplantar oblique band,” runs from the coronoid fossa, between the anterior and middle facets of the calcaneus, to the tubercle of the navicular.
Despite its name and implied function, the spring ligament does not have any elastic fibers or properties [8, 9]. The ligament spans the osseous gap between the sustentaculum tali of the calcaneus and the navicular bone and provides support for the head of the talus [4]. The spring ligament, together with the anterior and middle facets of the calcaneus, and the proximal articular surface of the navicular comprise the acetabulum pedis [2].
Fig. 5A Distention of spring ligament recess in 26-year-old woman with acute impaction injury of talar head. Sagittal (A) and coronal (B) fat-saturated T2 MR images show fluid communicating between talocalcaneonavicular joint and spring ligament recess (arrow). Note marrow edema (arrowhead) in talar head and neck.
Fig. 5B Distention of spring ligament recess in 26-year-old woman with acute impaction injury of talar head. Sagittal (A) and coronal (B) fat-saturated T2 MR images show fluid communicating between talocalcaneonavicular joint and spring ligament recess (arrow). Note marrow edema (arrowhead) in talar head and neck.
Fig. 6A Spring ligament recess in 40-year-old woman with acute ankle sprain. Sequential coronal fat-saturated proton density images show fluid-filled spring ligament recess (white arrow, B). There is acute high-grade partial tear of deltoid ligament with diffuse loss of normal architecture and increased signal (white arrow, A) as well as marrow contusions in talar neck and tibial plafond (arrowheads). There is also complete tear of anterior talofibular ligament (curved arrow, A). Accessory flexor digitorum longus muscle (asterisk, A) is noted.
Fig. 6B Spring ligament recess in 40-year-old woman with acute ankle sprain. Sequential coronal fat-saturated proton density images show fluid-filled spring ligament recess (white arrow, B). There is acute high-grade partial tear of deltoid ligament with diffuse loss of normal architecture and increased signal (white arrow, A) as well as marrow contusions in talar neck and tibial plafond (arrowheads). There is also complete tear of anterior talofibular ligament (curved arrow, A). Accessory flexor digitorum longus muscle (asterisk, A) is noted.
Posterior tibial tendon (PTT) dysfunction is the primary component of adult-acquired flatfoot deformity and hindfoot valgus. Although isolated PTT repair has led to limited results in terms of correcting flatfoot deformity, adjunctive repair of the spring ligament appears to improve surgical outcome [7]. The imaging features of spring ligament tears and insufficiency have been well described [3, 4]. While tears are best diagnosed by frank discontinuity of the ligament fibers [5, 10], the diagnosis of insufficiency is made by signal heterogeneity, attenuation, or thickening of the ligament. Acute spring ligament tears are related to trauma as opposed to spring ligament insufficiency, which is the result of gradual ligament attrition and stretching.
In all our cases, the spring ligament recess was visible on fluid-sensitive sequences in at least two orthogonal planes. The axial images best showed the recess's location between the medioplantar oblique and inferoplantar longitudinal components of the spring ligament. The recess measured on average 0.4 × 0.8 cm (transverse and craniocaudal) (range, 0.2–0.9 × 0.4–1.5 cm). It had a distinctive teardrop-shaped configuration on coronal and sagittal images and was nearly always oriented anteromedially in the axial plane, parallel to the plantar fibers of the spring ligament.
The talocalcaneonavicular joint is bordered by the talar head, the concave posterior surface of the navicular, the articular surface of the anterior process of the calcaneus, and the upper surface of the spring ligament [6]. In a recent study, this joint was termed the “talonavicular middle subtalar joint complex,” which occasionally communicates with the anterior subtalar joint [11]. Communication between the recess and the talocalcaneonavicular joint was noted in all of our cases on MR images in both the sagittal and coronal planes. This communication was grossly confirmed on the arthrographic cadaveric MR images, where fluid was noted to extend from the talonavicular joint injection site into the spring ligament recess. Furthermore, histologic dissections depicted the recess to have a synovial lining continuous with the anterior subtalar-talonavicular joint. To our knowledge, a spring ligament recess communicating with the talocalcaneonavicular joint has not yet been reported. We believe that the communication between these two structures is related to joint fluid distention. When fluid accumulates in the talocalcaneonavicular joint, it may decompress into the more dependent spring ligament recess. Therefore, the absence of a talocalcaneonavicular joint effusion does not necessarily militate against the presence of a spring ligament recess.
Fig. 7A Spring ligament recess containing intraarticular bodies. (Courtesy of Nomikos GC, Georgetown University Medical Center, Washington, DC) Axial fat-suppressed T2 (A) and coronal proton density (B) MR images depict distended spring ligament recess containing joint fluid and two loose bodies (black arrow), interposed between medioplantar oblique fibers (white arrow) and inferoplantar longitudinal fibers (curved arrow) of spring ligament.
Fig. 7B Spring ligament recess containing intraarticular bodies. (Courtesy of Nomikos GC, Georgetown University Medical Center, Washington, DC) Axial fat-suppressed T2 (A) and coronal proton density (B) MR images depict distended spring ligament recess containing joint fluid and two loose bodies (black arrow), interposed between medioplantar oblique fibers (white arrow) and inferoplantar longitudinal fibers (curved arrow) of spring ligament.
In a recent anatomic study, Melão et al. [6] attributed leakage of intraarticular contrast solution between the medioplantar oblique and inferoplantar longitudinal components of the spring ligament to regions of ligament weakness filled with fat, leading to an appearance of a “pseudotear.” We noted a fluid-filled spring ligament recess in the absence of MR findings of a spring ligament tear in 42 of our 49 patients. The band saw and histologic evaluation of our cadaveric specimen supports our belief that the communication between the talocalcaneonavicular joint and the spring ligament recess is related to an anatomic recess lined by synovial tissue and is not the result of a focal ligament weakness. This recess is analogous to the distention of the gastrocnemius-semimembranosus bursa and the iliopsoas bursa in the setting of knee and hip joint effusions, respectively.
Our findings suggest that visualization of the spring ligament recess may be promoted by the presence of a talocalcaneonavicular effusion as a result of trauma or arthritic processes of the hindfoot and midfoot. The main differential diagnosis of a fluid-distended spring ligament recess is a tear of the spring ligament, synovial cyst, and ganglion cyst. In our daily practice, we are often faced with this clinical dilemma. On the basis of the results of this study, the spring ligament recess can be distinguished from a spring ligament tear by its well-defined, contained borders, homogeneous fluid signal, and clear communicating neck extending between the medioplantar oblique and inferoplantar longitudinal components of the spring ligament as well as by the absence of thickening, fraying, and discontinuity of the spring ligament fibers.
Anterior talar head impaction and acute and chronic lateral ankle sprains were frequently found in our patient population (> 25%). There was also a trend toward a higher prevalence of talar head impaction with talocalcaneonavicular effusions. Talar head impaction has been previously reported secondary to inversion injury, acute dislocation at the talonavicular joint with talocuboid impaction, and traumatic disruption of the spring ligament [12]. In our case series, all but one of the 16 cases of talar head impaction injury were associated with lateral ankle sprains. Furthermore, in 25% (4/16) of those cases, there was also a tear of the spring ligament. We did not have any cases of talonavicular dislocation in our series. Future studies are needed to better analyze the epidemiology and associated injuries in the setting of talar head impaction. The spring ligament recess can also be distended in cases of talonavicular degenerative joint disease. This association is further supported by the presence of loose bodies identified within the spring ligament recess in a patient with talonavicular osteoarthrosis (Fig. 7A, 7B).
Our study has several limitations. We had a small study group with 49 prospectively collected patients. Provided clinical history for these patients was limited and we had no surgical correlation for our study group. Both cadaveric ankles came from the same patient.
In conclusion, we describe the presence of a synovium-lined recess of the talocalcaneonavicular joint extending between the plantar components of the spring ligament. Fluid signal within this recess should not be interpreted as indicative of a spring ligament tear. Visualization of the recess is facilitated by the presence of a native talocalcaneonavicular joint effusion or by intraarticular talonavicular injection of contrast solution. Talocalcaneonavicular effusion in the setting of acute impaction injury of the talar head and lateral ankle sprains are common associated findings.

Acknowledgments

We thank James Babb for his assistance in the statistical analysis of our data as well as George C. Nomikos for contributing the case illustrated in Figure 7A, 7B.

Footnotes

Address correspondence to K. R. Desai ([email protected]).
CME
This article is available for CME credit.
See www.arrs.org for more information.

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Information & Authors

Information

Published In

American Journal of Roentgenology
Pages: 1145 - 1150
PubMed: 21512083

History

Submitted: June 15, 2010
Accepted: October 12, 2010

Keywords

  1. anatomy
  2. ankle
  3. foot
  4. spring ligament
  5. talocalcaneonavicular joint

Authors

Affiliations

Kapil R. Desai
Department of Radiology, NYU Hospital for Joint Diseases, New York, NY.
Department of Pathology, NYU Hospital for Joint Diseases, New York, NY.
Present address: Department of Radiology, Mount Sinai School of Medicine, 1 Gustave L. Levy Pl, Box 1234, New York, NY 10128.
Luis S. Beltran
Department of Radiology, NYU Hospital for Joint Diseases, New York, NY.
Jenny T. Bencardino
Department of Radiology, NYU Hospital for Joint Diseases, New York, NY.
Zehava S. Rosenberg
Department of Radiology, NYU Hospital for Joint Diseases, New York, NY.
Catherine Petchprapa
Department of Radiology, NYU Hospital for Joint Diseases, New York, NY.
German Steiner
Department of Radiology, NYU Hospital for Joint Diseases, New York, NY.
Department of Pathology, NYU Hospital for Joint Diseases, New York, NY.

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