Sesamoid injuries of the toes

1. High-Yield Summary

• Anatomical Dual-Sesamoid Complex: The hallucal sesamoids (tibial/medial and fibular/lateral) are embedded within the flexor hallucis brevis (FHB) tendon and plantar plate apparatus beneath the first metatarsal head. They elevate the first metatarsal, amplify the mechanical moment arm of the FHB by over 30%, absorb 50% or more of forefoot impact during terminal stance, and protect the long flexor tendon within the intersesamoid groove. Lesser toe sesamoids are variable accessory structures (most prevalent at the hallux interphalangeal joint and the second or fifth metatarsophalangeal joints) that can develop mechanical impingement, osteochondritis, or dislocation.
• Tibial Predilection & Vascular Watershed: The medial (tibial) sesamoid is larger, sits directly beneath the principal weightbearing medial condyle of the first metatarsal head, carries approximately 60% of the hallucal load, and accounts for greater than 80% of all sesamoid stress fractures, osteonecrosis, and traumatic disruptions. Extraosseous blood supply enters predominantly via the proximal and plantar capsular attachments, predisposing the central watershed zone to delayed union, fibrous nonunion, and avascular necrosis.
• Diagnostic Benchmarks: Weightbearing anteroposterior (AP), lateral, and dedicated 30-degree axial sesamoid (tangential) radiographs are mandatory first-line projections. Differentiating an acute fracture from a congenital bipartite sesamoid hinges on radiographic morphology (sharp, irregular, non-corticated edges and lack of fit vs. smooth, rounded, sclerotic borders with combined enlargement) and bilateral comparative imaging (~25% bilaterality in bipartite variants). Thin-cut computed tomography (CT) is the definitive modality for bony architecture and union, while magnetic resonance imaging (MRI) is essential for diagnosing early stress reactions, avascular necrosis (Renander’s disease), and plantar plate avulsions.
• Conservative Nonoperative Priority: Initial management for acute nondisplaced fractures, stress fractures, and sesamoiditis requires strict offloading. Structured treatment utilizes a dancer’s pad (cutout beneath the sesamoid), a rigid carbon-fiber footplate with Morton’s extension, or 4 to 6 weeks of non-weightbearing immobilization in a pneumatic CAM boot or cast, achieving return-to-sport rates of approximately 85%.
• Surgical Principles & Deformity Prevention: Operative intervention is indicated for symptomatic nonunion refractory to 4 to 6 months of conservative therapy, displaced acute fractures (>2 mm displacement or >1 mm articular step-off), and fragmented osteonecrosis. Partial sesamoidectomy is preferred whenever possible to maintain FHB continuity. Total sesamoidectomy yields high rates of pain relief (>90%) but alters forefoot biomechanics: medial sesamoidectomy risks secondary hallux valgus, whereas lateral sesamoidectomy risks hallux varus. Complete bilateral sesamoidectomy of the hallux is strictly contraindicated due to catastrophic loss of intrinsic stabilization, producing severe cock-up claw deformity and transfer metatarsalgia.

2. Anatomy

The hallucal sesamoid complex is a sophisticated biomechanical suspension system positioned beneath the head of the first metatarsal. The complex comprises the tibial (medial) sesamoid, fibular (lateral) sesamoid, the intersesamoid ligament, the plantar plate, and the insertions of the intrinsic hallucal musculature.

Osseous & Articular Architecture

The plantar surface of the first metatarsal head features two distinct articular grooves—the medial and lateral sulci—separated by a central longitudinal bony crest called the crista. The tibial sesamoid articulates within the medial sulcus and is typically oval, elongate, and larger than the lateral counterpart. The fibular sesamoid articulates within the lateral sulcus and is rounder and more uniform. The articular surfaces of both sesamoids are covered with hyaline cartilage. The crista provides intrinsic coronal stability; erosion or flattening of the crista (frequently observed in advanced hallux valgus) permits lateral subluxation of the sesamoid apparatus.

Musculotendinous & Ligamentous Attachments

• Tibial Sesamoid Complex: Receives the medial belly of the flexor hallucis brevis (FHB), the dynamic tendon fibers of the abductor hallucis, the medial metatarsosesamoid suspensory ligament, and the thick medial sesamophalangeal ligament inserting into the plantar tubercle of the proximal phalanx base.
• Fibular Sesamoid Complex: Receives the lateral belly of the FHB, the conjoined tendon of the adductor hallucis (transverse and oblique heads), the lateral metatarsosesamoid suspensory ligament, and the lateral sesamophalangeal ligament.
• Intersesamoid Ligament & Plantar Plate: A robust, non-yielding fibrous band bridges the two sesamoids transversely, creating the roof of the fibro-osseous tunnel through which the flexor hallucis longus (FHL) tendon passes. Distally, both sesamoids are anchored to the base of the proximal phalanx by the thick fibrocartilaginous plantar plate, while proximally they attach to the metatarsal neck via a thinner, elastic capsular apron.
• Lesser Toe Sesamoids: Accessory sesamoid bones occur regularly throughout the foot. The interphalangeal (IP) joint sesamoid of the hallux resides within the plantar capsule of the IP joint in 4% to 13% of individuals. Plantar sesamoids of the lesser metatarsophalangeal joints occur most commonly beneath the second (1% to 2%) and fifth (4% to 10%) metatarsal heads within the plantar plate.

Vascular Anatomy

The vascular supply to the hallucal sesamoids is precarious. Arterial supply is derived from the first plantar metatarsal artery (branch of the deep plantar arch) and the medial plantar artery. Small penetrating arterioles enter the bones primarily through their non-articular proximal and peripheral plantar capsular attachments. Intraosseous microvasculature flows in a retrograde proximal-to-distal direction. This layout leaves the central and distal poles vulnerable to microvascular disruption during repetitive impact or transverse fracture, explaining the high clinical rate of avascular necrosis and delayed healing.

Neurovascular Danger Zones & Surgical Planes

• Medial Plantar Proper Digital Nerve: Courses along the plantomedial aspect of the first metatarsophalangeal joint, directly adjacent to the inferior border of the tibial sesamoid. A mid-axial or slightly dorsal medial longitudinal incision protects this nerve, whereas an excessively plantar incision risks direct laceration or painful terminal neuroma formation.
• First Webspace Deep Peroneal & Lateral Plantar Digital Bundles: The lateral plantar digital nerve to the hallux and terminal branches of the deep peroneal nerve course in the first intermetatarsal space immediately dorsal and lateral to the fibular sesamoid. When performing a dorsal first webspace approach, blunt dissection deep to the deep transverse metatarsal ligament and gentle medial retraction are essential to prevent digital dysesthesias.
• Flexor Hallucis Longus (FHL) Tendon: Located centrally in the groove between the tibial and fibular sesamoids. Subperiosteal dissection along the sesamoid margins is mandatory during sesamoidectomy to avoid direct tendon laceration.

3. Pathogenesis

Pathologic conditions affecting the sesamoids span acute traumatic fractures, microvascular ischemic collapse, chronic mechanical stress failure, and ligamentous avulsions.

Biomechanics of Forefoot Loading

During the normal gait cycle, peak force beneath the first metatarsal head reaches 50% to 60% of total body weight during terminal stance and push-off. In high-impact athletic activities—including sprinting, jumping, and classical dance (relevé and demi-pointe positions)—ground reaction forces transmitted across the hallucal sesamoids can exceed 300% to 500% of body weight. The tibial sesamoid sustains the majority of this load due to its direct vertical alignment beneath the medial metatarsal condyle.

Mechanisms of Failure

• Acute Traumatic Fractures: Occur secondary to high-energy axial impact (landing from a significant height directly onto the forefoot) or sudden forced hyperdorsiflexion of the first MTP joint. Hyperdorsiflexion produces intense tensile loading across the strong sesamophalangeal ligaments, creating transverse or avulsion fracture patterns. Direct impact typically results in comminuted or crushed fracture configurations.
• Stress Fractures & Nonunion: Repetitive cyclical microtrauma without adequate recovery leads to osteoclastic resorption exceeding osteoblastic bone formation. Continued athletic impact converts microtrabecular stress reactions into frank cortical fracture lines. The watershed intraosseous blood supply, combined with continuous distraction forces from the contracting FHB muscle belly, creates an adverse biological and biomechanical environment, leading to high nonunion rates without early immobilization.
• Sesamoiditis: Represents an overuse inflammatory disorder encompassing chondromalacia of the sesamoid-metatarsal articulation, osteoperiostitis, and peritendinitis within the FHB envelope. Bony architecture remains intact without cortical discontinuity on high-resolution imaging.
• Osteonecrosis (Renander’s Disease): Post-traumatic vascular disruption or insidious microthrombosis produces ischemic bone necrosis. The affected sesamoid undergoes trabecular necrosis, microfracture, structural collapse, and subsequent fragmentation, characterized by osteosclerosis and cystic degeneration.
• Sesamoid Complex Dislocation & Turf Toe: Forced extreme hyperextension of the first MTP joint tears the distal sesamophalangeal ligaments and plantar plate. The sesamoids are drawn proximally by the unopposed tone of the FHB muscle bellies, destabilizing the entire first ray.
• Lesser Toe Sesamoid Pathologies: The hallux IP joint sesamoid can undergo mechanical friction leading to painful hyperkeratosis or can become incarcerated within the joint space following hyperextension trauma, causing an irreducible IP joint dislocation. Lesser MTP sesamoids under the second or fifth metatarsal heads can develop painful intractable plantar keratomas, stress fractures, or localized osteonecrosis.

4. Natural History

Sesamoid pathology represents approximately 9% to 12% of all great toe conditions and 1% to 2% of athletic running injuries. There is a strong predilection for individuals engaged in activities demanding repetitive forefoot loading, including ballet dancers, gymnasts, track-and-field sprinters, distance runners, football players, and basketball players.

The tibial sesamoid is involved in 80% to 85% of cases, while the fibular sesamoid accounts for 15% to 20%. Isolated lesser toe sesamoid injuries are rare, representing fewer than 2% of all sesamoid consultations.

Untreated or unrecognized sesamoid injuries follow an unfavorable course:

• Progression to Chronic Nonunion: Up to 40% to 50% of sesamoid stress fractures that are not immobilized early progress to established fibrous nonunion or pseudoarthrosis. Chronic nonunion leads to persistent antalgic gait, hypertrophic fragment enlargement, and secondary attrition of the adjacent FHL tendon.
• Secondary Osteoarthritis: Chronic articular step-off from displaced fractures or collapse from osteonecrosis generates severe sesamoid-metatarsal arthrosis. This causes loss of first MTP joint range of motion, mechanical crepitus, and progression toward hallux rigidus.
• Altered Forefoot Mechanics: Patients develop an antalgic gait pattern characterized by supination of the foot to offload the painful medial forefoot. This compensatory gait significantly increases load on the lateral column, commonly producing secondary transfer metatarsalgia, stress fractures of the second, third, or fifth metatarsals, and peroneal tendinopathy.

5. Clinical Presentation

History

• Symptom Onset: Inquire whether pain began abruptly following a specific event (indicative of acute traumatic fracture or turf toe avulsion) or developed insidiously over weeks to months with escalating athletic mileage (indicative of sesamoiditis or stress fracture).
• Aggravating Factors: Discomfort is characteristically aggravated by walking barefoot on hard floors, wearing flexible thin-soled shoes or high-heeled footwear, and running or jumping. In dancers, pain is intensely exacerbated during the relevé position.
• Mechanical Symptoms: Locking, popping, or painful snapping during push-off suggests a displaced osteochondral fragment, entrapment of an IP joint sesamoid, or concurrent FHL tenosynovitis.
• Neurologic Complaints: Numbness, paresthesias, or burning along the plantomedial aspect of the great toe points toward irritation or entrapment of the medial plantar digital nerve.

Physical Examination

Examination begins with visual inspection during standing and gait analysis. Look for localized plantar swelling, ecchymosis, intractable keratosis beneath the first or lesser metatarsal heads, and an antalgic gait with lateral border ground contact.

6. Imaging and Diagnostic Studies

Plain Radiography

The standard radiographic evaluation requires weightbearing AP, lateral, and dedicated sesamoid axial projections:

• Weightbearing AP & Lateral Views: Assess overall first ray alignment, intermetatarsal angle, hallucal joint space, and longitudinal sesamoid position relative to the metatarsal neck. Compare sesamoid position with the contralateral uninjured foot to identify proximal retraction indicative of plantar plate avulsion (>3 mm asymmetry is diagnostic of complete rupture).
• Axial (Tangential) Sesamoid View: Taken with the patient prone or standing with the toes hyperextended on a custom wedge block, directing the beam tangentially along the sole of the foot. Essential for evaluating the articular space of each sesamoid facet, integrity of the central crista, coronal subluxation, and separating the medial and lateral sesamoids without bony overlap.
• Internal and External Oblique Projections: Helpful to project the medial (internal oblique) or lateral (external oblique) sesamoid profile without metatarsal head overlap.

Bipartite Sesamoid versus Acute Fracture Differentiation

Congenital bipartite sesamoids occur in 10% to 14% of the population, are bilateral in approximately 25% of individuals, and involve the tibial sesamoid in over 85% of occurrences. Distinguishing a congenital bipartite variant from an acute traumatic fracture is a critical diagnostic challenge.

Advanced Imaging Modalities

• Computed Tomography (CT): Thin-cut (0.5 to 1.0 mm) helical CT is the gold standard for defining cortical continuity, fragment displacement, nonunion gap dimensions, and intra-articular step-off. It provides definitive confirmation when distinguishing between fibrous union and persistent bony nonunion.
• Magnetic Resonance Imaging (MRI): Highly sensitive for diagnosing early-stage stress reactions prior to the appearance of radiographically visible cortical lines (evidenced by extensive marrow edema on T2-weighted and STIR sequences). MRI is also the diagnostic investigation of choice for identifying osteonecrosis (manifested by low signal intensity on both T1 and T2 sequences with non-enhancement on gadolinium contrast), plantar plate tears, intersesamoid ligament disruption, and concurrent FHL pathology.
• Diagnostic Ultrasound: High-frequency dynamic sonography can evaluate FHL tendon excursion, assess bursal thickening, identify hypoechoic hematoma around the plantar plate, and guide diagnostic or therapeutic local anesthetic injections.

7. Classification

Sesamoid pathology is classified based on etiology, anatomical disruption, and chronicity to guide treatment decisions.

8. Treatment

Nonoperative / Conservative Management

Nonoperative care is the standard first-line treatment for all sesamoid injuries with intact alignment, acute nondisplaced fractures, stress fractures, sesamoiditis, and symptomatic bipartite variants:

• Phase 1: Acute Immobilization & Offloading (Weeks 0–6): For acute nondisplaced fractures and acute stress fractures, patients are placed in a non-weightbearing below-knee fiberglass cast or a rigid pneumatic walking boot with a non-weightbearing crutch protocol for 4 to 6 weeks. Complete elimination of ground reaction force is necessary to overcome the hypovascular watershed zone.
• Phase 2: Protected Weightbearing & Orthoses (Weeks 6–12): Following radiographic and clinical improvement, weightbearing is initiated in a supportive shoe fitted with a custom orthosis featuring a dancer’s pad (a felt or silicone pad placed proximal and lateral to the first metatarsal head, creating a recessed well that suspends the sesamoid without ground contact). Alternatively, a full-length rigid carbon-fiber footplate with a built-in Morton’s extension is used to eliminate first MTP extension during gait.
• Adjunctive Biologic & Physical Therapies: Low-intensity pulsed ultrasound (LIPUS) or pulsed electromagnetic field (PEMF) bone stimulation may be prescribed for high-risk stress fractures or delayed unions. Contrast baths, gentle passive range-of-motion exercises, and intrinsic foot muscle strengthening commence once bone tenderness resolves.
• Corticosteroid Caution: Corticosteroid injections into or adjacent to the hallucal sesamoids must be avoided or used with extreme caution. Steroid infiltration carries high risks of plantar fat pad atrophy, spontaneous plantar plate rupture, avascular necrosis acceleration, and intractable chronic metatarsalgia.

Operative Management

Surgical intervention is indicated when structured conservative care fails or when initial presentation reveals gross mechanical displacement. The goals of surgery are to eradicate pain, restore a functional weightbearing surface, maintain the intrinsic flexor moment arm, and prevent postoperative angular toe deformity.

• Partial Sesamoidectomy (Fragment Excision): The preferred surgical choice when pathology is confined to either the proximal or distal pole (such as polar nonunions, small avulsion fractures, or bipartite synchondrosis separations). The ununited fragment is carefully enucleated subperiosteally while strictly preserving the attachment of the FHB tendon and sesamophalangeal ligament to the remaining stable pole. This preserves the functional lever arm of the first ray and allows earlier return to activity (~7 weeks).
• Open Reduction and Internal Fixation (ORIF): Indicated for acute displaced fractures (>2 mm) or transverse nonunions of the tibial sesamoid in high-demand competitive athletes where total sesamoid volume must be preserved to maximize push-off strength. Through a medial longitudinal approach, the fracture gap is debrided of fibrous tissue, decorticated, packed with autologous cancellous bone graft (harvested from the medial calcaneus or proximal tibia), and compressed using a low-profile 1.5 mm to 2.5 mm cannulated headless screw placed in a retrograde or antegrade fashion.
• Complete Tibial (Medial) Sesamoidectomy: Performed via a medial mid-axial longitudinal incision along the first metatarsophalangeal joint. The medial plantar digital nerve is visualized and gently mobilized plantarly. The capsule is incised longitudinally, and the tibial sesamoid is shelled out of its osteotendinous envelope using sharp subperiosteal dissection, taking care not to violate the central intersesamoid ligament or the adjacent FHL tendon. Following excision, the defect in the medial FHB tendon and abductor hallucis sleeve must be meticulously repaired with heavy non-absorbable sutures to balance the joint and prevent secondary hallux valgus deformity.
• Complete Fibular (Lateral) Sesamoidectomy: Performed through a dorsal first webspace incision or a plantolateral approach. The dorsal approach spares the plantar weightbearing skin: the deep transverse metatarsal ligament is divided, the adductor hallucis tendon is detached from the base of the proximal phalanx, and the fibular sesamoid is delivered into the intermetatarsal space for excision. The conjoined tendon and lateral capsule are subsequently reconstructed to avoid secondary hallux varus deformity.
• Excision of Lesser Toe Sesamoids: For symptomatic lesser toe sesamoids (such as an irreducible hallux IP joint sesamoid or a painful second/fifth MTP sesamoid), a direct longitudinal plantar or dorsal-plantar approach is used to enucleate the accessory bone and repair the plantar plate.

Indications & Contraindications

Indications for Surgery:

• Established symptomatic nonunion or persistent severe pain refractory to at least 4 to 6 months of nonoperative management.
• Acute traumatic fracture with displacement >2 mm, articular step-off >1 mm, or gross comminution.
• Stage IV osteonecrosis with collapse, fragmentation, and joint incongruity.
• Acute turf toe injury with complete tear of the sesamophalangeal ligament and >3 mm proximal retraction of the sesamoid complex.
• Irreducible dorsal dislocation of the hallux IP joint caused by an entrapped interphalangeal sesamoid.

Contraindications to Surgery:

• Bilateral Hallucal Sesamoidectomy (Absolute Contraindication): Excision of both the tibial and fibular sesamoids in the same foot is strictly contraindicated. Loss of both sesamoids destroys the FHB insertion, leaving the extensor hallucis longus unopposed and producing a severe, disabling cock-up claw deformity, complete loss of push-off power, and intractable transfer metatarsalgia.
• Asymptomatic radiographic findings (incidental bipartite sesamoid or asymptomatic radiographic nonunion).
• Severe peripheral vascular disease, active cutaneous infection at the surgical site, or uncontrolled diabetic neuropathy.

9. Outcome

Clinical outcomes following nonoperative and operative treatment of sesamoid disorders are favorable when treatment is individualized based on fracture pattern and patient functional demands.

• Nonoperative Treatment Success: Systematic reviews demonstrate that approximately 85% of athletes managed conservatively for sesamoid stress fractures return successfully to their pre-injury level of sports participation. However, recovery requires substantial patience, with mean return-to-play timelines spanning 12 to 24 weeks. High-risk stress fractures managed with early non-weightbearing casting demonstrate significantly higher union rates than those treated with continued weightbearing in soft footwear.
• Surgical Efficacy of Sesamoidectomy: In systematic reviews encompassing 442 feet, complete or partial sesamoidectomy achieved good-to-excellent clinical results in over 90% of patients, with complete pain relief documented in 94.8%. The overall postoperative complication rate was 22.4%, with most complications related to minor alignment drift or localized scar sensitivity.
• Partial versus Complete Excision Recovery Timelines: In athletic cohorts, partial sesamoidectomy yields significantly faster return to full activity (mean 7.2 weeks) compared to complete sesamoidectomy (mean 11.2 to 11.8 weeks). Preserving the uninjured pole maintains tension in the sesamophalangeal apparatus and minimizes risk of sagittal or coronal drift.
• Internal Fixation & Bone Grafting: Selected series of competitive athletes treated with open reduction, autologous bone grafting, and headless compression screw fixation for nonunion report union rates exceeding 90%, with successful preservation of full push-off strength and return to competitive performance within 12 to 16 weeks.

10. Complications

Complications following sesamoid injuries and surgical intervention can produce significant functional impairment. Structured categorization guides prevention and management.

11. Pearls and Pitfalls

• The “Preserve the Pole” Principle: When operating for ununited polar fractures or bipartite synchondrosis separations, always prioritize partial sesamoidectomy over complete excision. Removing only the symptomatic, non-functional fragment while leaving the major pole attached preserves the FHB tendon insertion, maintains joint balance, and cuts recovery time in half.
• Sub-Axial Medial Incision Design: When exposing the tibial sesamoid, place the longitudinal incision slightly dorsal to the true mid-axial junction between plantar and dorsal skin. This guarantees direct visualization of the medial plantar proper digital nerve, prevents painful plantar scar formation, and leaves a sturdy inferior soft tissue cuff for anatomical capsulodesis.
• Mandatory Intrinsic Sleeve Reconstruction: Never leave the gap in the FHB tendon open after sesamoidectomy. Meticulous longitudinal repair of the flexor sleeve with heavy non-absorbable mattress sutures restores intrinsic tension and prevents angular deviation (hallux valgus or varus).
• The Bilateral Sesamoid Axial View: Never interpret unilateral sesamoid radiographs in isolation when evaluating potential fractures. Obtain bilateral weightbearing axial sesamoid views to assess congenital bipartite anatomy, which is bilateral in 25% of individuals.
• The Cardinal Prohibition Against Dual Excision: Never excise both the tibial and fibular sesamoids in the same foot. Complete loss of the hallucal sesamoid apparatus produces devastating functional impairment, severe cock-up claw deformity, push-off failure, and intractable transfer metatarsalgia.
• Avoid Plantar Corticosteroid Infiltration: Resisting the urge to inject corticosteroids into the acute or subacute sesamoid region protects the patient against accelerated osteonecrosis, irreversible plantar fat pad atrophy, and spontaneous rupture of the plantar plate.
• Beware the Irreducible Hallux IP Joint Dislocation: When encountering a dislocated hallux interphalangeal joint that fails closed reduction, suspect an incarcerated interphalangeal sesamoid. Repeated forceful closed manipulations risk cartilage damage and buttonholing of the plantar plate. Perform open reduction through a dorsal or medial approach to extricate the entrapped sesamoid.

12. Controversy

ORIF with Bone Grafting versus Sesamoidectomy in Elite Athletes

In high-demand jumping athletes, sprinters, and classical dancers with established transverse sesamoid nonunions, debate persists regarding the ideal surgical strategy. Advocates of open reduction, autologous bone grafting, and headless screw fixation emphasize that restoring the native sesamoid preserves normal first MTP contact mechanics, maintains optimal FHB moment arms, and safeguards explosive push-off torque. However, detractors point out the technical difficulty of achieving stable compression in small, osteopenic, or sclerotic fragments, risk of hardware penetration into the articular surface, prolonged healing requirements (12 to 16 weeks), and nonunion rates of 10% to 15%. In contrast, partial or complete sesamoidectomy offers a reliable, rapid recovery (7 to 11 weeks) with high patient satisfaction (>90%), provided soft tissue sleeves are balanced.

Surgical Approach for Fibular Sesamoidectomy: Dorsal Webspace versus Direct Plantar

The optimal approach for fibular sesamoidectomy remains contested. The dorsal first webspace approach completely avoids a plantar weightbearing scar, eliminating risks of intractable plantar keratosis or painful weightbearing scars. However, it requires division of the deep transverse metatarsal ligament, extensive lateral soft tissue release, and blind or indirect mobilization of the sesamoid, risking iatrogenic injury to the lateral digital nerve and adductor insertion. The direct plantolateral longitudinal approach offers direct, unobstructed anatomical exposure with minimal soft tissue disruption, but carries a 5% to 10% risk of painful plantar hyperkeratotic scar formation, requiring careful deep dermal closure and offloading protocols.

Interpreting Asymptomatic Bipartite Edema on High-Resolution MRI

With the widespread availability of high-resolution 3.0T MRI, subtle bone marrow edema is frequently detected across the synchondrosis of asymptomatic or minimally symptomatic bipartite sesamoids in active runners. Clinicians face the dilemma of distinguishing physiologic stress remodeling from an active, unstable synchondrosis disruption or early stress fracture. Current consensus recommends treating the patient’s focal physical examination findings rather than isolated MRI signal changes, avoiding unnecessary prolonged immobilization unless true localized point tenderness and mechanical pain on resisted flexion are reproduced.

13. Evidence-Based Synthesis

Modern clinical decision-making is grounded in high-quality randomized controlled trials and prospective registry analyses, corroborated by seminal biomechanical and anatomical descriptions.

14. References

• Robertson GAJ, Goffin JS, Wood AM. Return to sport following stress fractures of the great toe sesamoids: a systematic review. British Medical Bulletin. 2017. doi:10.1093/bmb/ldx010 [Level I: Systematic Review / Meta-Analysis]
• Shimozono Y, Hurley ET, Brown AJ, Kennedy JG. Sesamoidectomy for Hallux Sesamoid Disorders: A Systematic Review. The Journal of Foot and Ankle Surgery. 2018. doi:10.1053/j.jfas.2018.03.044 [Level I: Systematic Review / Meta-Analysis]
• Saxena A, Krisdakumtorn T. Return to Activity after Sesamoidectomy in Athletically Active Individuals. Foot & Ankle International. 2003. doi:10.1177/107110070302400507 [Level IV: Clinical Case Series]
• Dedmond BT, Cory JW, McBryde A. The Hallucal Sesamoid Complex. Journal of the American Academy of Orthopaedic Surgeons. 2006. doi:10.5435/00124635-200612000-00006 [Level V: Seminal Narrative & Consensus Review]
• Boden BP, Osbahr DC. High-Risk Stress Fractures: Evaluation and Treatment. Journal of the American Academy of Orthopaedic Surgeons. 2000. doi:10.5435/00124635-200011000-00002 [Level V: Seminal Narrative & Consensus Review]

15. Master Class Pro-Tip

When performing a complete tibial sesamoidectomy, operative success depends upon three technical tenets: nerve protection, subperiosteal shell dissection, and anatomical capsular reconstruction. Place your incision 2 mm dorsal to the mid-axial line to effortlessly reflect the medial proper digital nerve plantarly within its protective soft tissue flap. Incise the capsule longitudinally directly over the equator of the sesamoid bone and develop the plane subperiosteally using a small curved Beaver blade or fine elevator, keeping the instrument tip strictly against bone at all times. This protects both the underlying FHL tendon in the intersesamoid groove and the vital plantolateral intersesamoid ligament. Once the bone is enucleated, never close the skin over an open void: place the hallux in 5 degrees of slight plantarflexion and neutral ab/adduction, and perform a robust end-to-end mattress repair of the medial FHB tendon and abductor hallucis sleeve using 2-0 non-absorbable braided suture. This simple structural step restores intrinsic tension, eliminates the dead space that breeds hematomas, and reliably prevents the development of secondary hallux valgus deformity.

Master Class Surgical Pearl: Operative Technique for Hallucal Sesamoidectomy