Abstract
Instability of the fourth and fifth tarsometatarsal (TMT) joints is an uncommon cause of chronic dorsolateral midfoot pain and may be underrecognized or misdiagnosed due to subtle or nonspecific imaging findings. Injuries involving the calcaneocuboid and lateral column ligament complexes may contribute to persistent instability following ankle or midfoot trauma. When conservative management fails, surgical stabilization may be required while preserving physiologic motion of the lateral column. The purpose of this report is to describe the diagnosis and surgical management of chronic lateral column instability of the fourth and fifth tarsometatarsal joints using motion-preserving synthetic ligament augmentation.
An 18-year-old female presented with persistent dorsolateral left midfoot pain and instability following a running injury. Initial radiographs were unremarkable, and MRI demonstrated mild marrow edema at the base of the fifth metatarsal without discrete ligament rupture. Despite immobilization, bracing, anti-inflammatory therapy, and physical therapy, the patient developed persistent pain, instability, and functional limitation with prolonged standing.
The patient underwent open stabilization of the fourth and fifth tarsometatarsal joints using a synthetic polyurethane urea ligament augmentation scaffold. Intraoperatively, gross instability and subluxation of the fourth and fifth TMT joints were confirmed. Ligament augmentation was performed spanning the fourth metatarsal to the cuboid and the cuboid to the fifth metatarsal to restore lateral column stability.
At one-year follow-up, the patient demonstrated stable lateral column alignment with no recurrent instability and minimal residual pain. PROMIS patient-reported outcome measures demonstrated low pain intensity and minimal functional interference.
Chronic instability of the fourth and fifth TMT joints can produce persistent dorsolateral midfoot pain despite normal imaging findings. Motion-preserving reconstruction using synthetic ligament augmentation scaffolds may restore lateral column stability and provide favorable clinical and patient-reported outcomes.
Level of Clinical Evidence: 4
Introduction
Injuries to the tarsometatarsal (TMT) complex most commonly involve the medial column and are typically discussed in the context of Lisfranc injuries. In contrast, instability of the lateral column involving the fourth and fifth tarsometatarsal joints is relatively uncommon and may be easily overlooked. , Patients often present with persistent dorsolateral midfoot pain, subtle instability, and activity-related symptoms despite normal radiographic findings. As a result, diagnosis is frequently delayed and symptoms may persist despite prolonged conservative management.
The lateral column of the foot plays an important biomechanical role during gait, providing flexibility that allows the foot to adapt to uneven terrain and dissipate ground reaction forces. Unlike the relatively rigid medial column, the fourth and fifth tarsometatarsal joints demonstrate greater physiologic mobility, contributing to shock absorption and terrain accommodation during stance and propulsion. The cuboid serves as a key mechanical link between the calcaneocuboid joint and the lateral metatarsals , transmitting forces across the lateral midfoot and contributing to overall column stability. Disruption of ligamentous stabilizers within this region ,, may therefore produce subtle but clinically significant instability, resulting in persistent dorsolateral midfoot pain even when standard radiographs appear normal.
In the present case, the primary pathology involved dynamic dorsal capsuloligamentous instability of the fourth and fifth tarsometatarsal joints identified during clinical and intraoperative stress examination. Previous biomechanical and clinical studies have emphasized the functional mobility of the lateral tarsometatarsal joints and the potential biomechanical consequences of lateral column arthrodesis. , Because preservation of physiologic lateral column motion is desirable when possible, motion-preserving reconstruction techniques that restore ligamentous stability without fusion may represent an attractive surgical option in selected patients.
Augmentation and ligament reconstruction techniques for fourth and fifth tarsometatarsal instability remain sparsely described in the literature. Prior operative strategies have largely focused on calcaneocuboid instability, including dorsal ligament reefing with periosteal flap augmentation ,, and tendon-based reconstructions utilizing autogenous gracilis grafts to recreate dorsal and plantar ligamentous restraints. Because the lateral column functions as an integrated biomechanical unit, reconstructive principles described for calcaneocuboid instability may also have relevance to adjacent fourth and fifth tarsometatarsal instability patterns. The only published clinical series specifically addressing fourth metatarsal-cuboid instability was reported by Saxena and Hofer, who described a dorsal suture-anchor construct designed to reinforce the fourth TMT ligament complex. Their technique utilized knotless biocomposite anchors spanning the cuboid and fourth metatarsal base to recreate the dorsal ligamentous restraint and restore lateral column stability. In their series of five female patients, including adolescent athletes, all patients achieved improved mechanical and functional stability with return to activity at a mean of 4.4 months and significant improvement in postoperative Roles and Maudsley scores. These findings suggest that augmentation-based stabilization techniques may provide a viable alternative to traditional fixation methods in select cases of chronic lateral TMT instability.
To our knowledge, this represents the first reported use of a synthetic polyurethane urea ligament augmentation scaffold for chronic instability of the fourth and fifth tarsometatarsal joints. The purpose of this report is to describe the diagnosis and surgical management of chronic fourth and fifth tarsometatarsal instability treated with a motion-preserving synthetic ligament augmentation scaffold. One-year clinical, radiographic, and patient-reported outcomes using PROMIS measures are presented.
Case report
An 18-year-old female presented with persistent dorsolateral midfoot pain after a traumatic running injury. She was initially evaluated in the emergency department and treated with a walking boot and short-term crutch use; however, work and activity demands limited her ability to maintain consistent immobilization.
Over the following weeks, she developed persistent activity-related pain localized to the dorsolateral midfoot, associated with subjective instability, altered gait, and progressive difficulty with prolonged standing. Conservative treatment, including immobilization, bracing, anti-inflammatory medication, and physical therapy, failed to provide adequate symptom relief.
Physical examination demonstrated focal tenderness over the dorsolateral midfoot, most pronounced at the bases of the fourth and fifth metatarsals and the fourth and fifth tarsometatarsal joints. Neurovascular examination was normal. Clinical stress examination demonstrated painful sagittal plane instability with reproducible dorsal translation and subluxation of the fourth and fifth tarsometatarsal joints compared with the contralateral side, reproducing the patient’s characteristic dorsolateral midfoot pain.
Weightbearing radiographs demonstrated no acute osseous abnormality or malalignment ( Fig. 1 ). MRI demonstrated mild marrow edema at the base of the fifth metatarsal with subtle plantar soft tissue edema, but no discrete ligament rupture ( Fig. 2 ). Given persistent symptoms, functional limitation, clinical instability, and failure of conservative management, surgical stabilization was recommended.
Preoperative radiographs of the left foot.
Anteroposterior and oblique weightbearing radiographs demonstrating normal alignment of the midfoot without evidence of fracture, dislocation, or other acute osseous pathology despite the patient’s persistent dorsolateral midfoot pain.
Preoperative MRI of the left foot.
Magnetic resonance imaging demonstrating focal marrow edema at the base of the fifth metatarsal corresponding to the patient’s area of pain. No discrete fracture or ligament rupture was identified, highlighting the subtle imaging findings often associated with lateral column instability.
Operative technique
Open stabilization of the fourth and fifth tarsometatarsal joints was performed on 2/24/2025 under general anesthesia. Intraoperative stress examination confirmed dynamic dorsal instability and subluxation of the fourth and fifth tarsometatarsal joints with manual stress across the lateral column.
A dorsolateral incision was made over the fourth and fifth tarsometatarsal joints. Layered dissection was carried down to the joint region, and the extensor digitorum brevis was reflected dorsally and medially. Neurovascular structures were carefully protected. The bases of the fourth and fifth metatarsals and the cuboid were exposed. Minimal periosteal and capsular reflection was performed to allow visualization while preserving soft tissue attachments.
A 12 cm synthetic polyurethane urea ligament augmentation scaffold was utilized for reconstruction of the dorsal lateral column ligament complex. The construct was placed dorsally spanning the cuboid to the bases of the fourth and fifth metatarsals ( Fig. 3 ). The scaffold was intended to provide immediate mechanical stabilization while facilitating gradual biologic soft tissue incorporation over time. Manual reduction of the fourth and fifth tarsometatarsal joints was performed prior to final tensioning of the construct. Instability was noted to be predominantly sagittal plane intraoperatively with dorsal translation and subluxation during manual stress testing. Fixation was achieved using intraosseous 3.85 mm anchors placed within the fourth and fifth metatarsal bases and a 5.0 mm anchor placed within the cuboid. Anchors were inserted perpendicular to the long axis of the involved bones while avoiding cortical disruption. The scaffold was tensioned to restore lateral column stability while preserving physiologic motion, and excess scaffold material was trimmed following final fixation. Repeat manual and fluoroscopic stress examination demonstrated restoration of stability across the fourth and fifth tarsometatarsal joints without residual subluxation. Fluoroscopy confirmed appropriate lateral column alignment without joint malreduction.
