Abstract
Reconstructing extensive bone loss in the foot after trauma poses a significant surgical challenge. The challenge becomes even greater when the injury involves weight-bearing structures. This case report presents the use of a custom 3D-printed implant to reconstruct the second metatarsal following loss of its distal portion. This injury was further complicated by dislocations of the third to fifth metatarsophalangeal joints with plantar protrusion of the third and fourth metatarsal heads through the foot. Additionally, a dislocation of the first tarsometatarsal joint was also present. A staged surgical approach was employed consisting of (1) irrigation and debridement of the open wound, reduction of the dislocated joints and placement of a temporary antibiotic spacer into the distal second metatarsal space (2) insertion of a fibular strut allograft into the distal second metatarsal space while the custom 3D implant was being designed and internal fixation of the first tarsometatarsal joint using a bridge plate and (3) definitive reconstruction of the second metatarsal using a patient-specific 3D-printed implant.
Our surgical procedure restored foot anatomy and enabled our patient to return to full weight bearing. Postoperative radiographs confirmed excellent alignment, stability, and integration of the implant. This case highlights the transformative potential of 3D printing technology in addressing critical bone loss and restoring function in complex foot trauma. Custom implants offer significant advantages over traditional bone grafting techniques providing a promising solution for complex orthopedic reconstructions.
Introduction
The second metatarsal plays an important role in foot biomechanics contributing significantly to load distribution, sagittal plane stability and overall structural integrity during gait. During the stance phase of gait, nearly 45 % of the body’s force passes through the head of the second metatarsal placing it under significant bending strain . Disruption or loss of this bone, whether due to trauma, infection or prior surgical intervention can result in marked forefoot instability, altered pressure dynamics and chronic pain all of which may severely impair a patient’s function and quality of life.
Traditional reconstructive techniques including autografts and allografts remain the mainstay in managing segmental metatarsal defects. However, these approaches are not without limitations. Challenges such as donor site morbidity, poor anatomical conformity, and suboptimal long-term biomechanical performance continue to affect clinical outcomes. Furthermore, these methods may fail to adequately restore native foot mechanics particularly in cases involving extensive or anatomically complex defects. ,
Recent advancements in 3D printing technology have led to the development of patient-specific implants. These custom implants offer precise anatomical replication, enhanced structural durability and improved functional restoration. In this report we present a case of traumatic distal second metatarsal loss reconstructed using a custom 3D-printed titanium implant. This case illustrates the successful use of 3D printing in complex forefoot reconstruction and highlights its potential to improve surgical outcomes in foot and ankle surgery.
Case report
Clinical presentation
A 30-year-old male with a medical history significant of seizure disorder presented to the emergency room following a high-energy motorcycle accident. The injury resulted in significant trauma to his left foot including the loss of the distal portion of the second metatarsal, dislocations of the first tarsometatarsal joint and the third to fifth metatarsophalangeal joints ( Fig. 1 ). The third and fourth metatarsals were protruding through the plantar aspect of the foot ( Fig. 2 ). Subsequently, his friend returned to the scene of the accident, located the missing second metatarsal bone fragment and brought it to the emergency department in an effort to assist with potential reconstructive options.
Lateral view (A) and AP view (B) of the left foot demonstrate dislocation of the first tarsometatarsal joint, a displaced second metatarsal fracture with loss of its distal segment, lateral and plantar dislocations of the third through fifth metatarsophalangeal joints.
Clinical photo shows plantar protrusion of the third and fourth metatarsal heads.
Initial management
Surgery 1: emergency surgery
The patient was taken to the operating room, where wound cultures were obtained followed by irrigation and debridement. A closed reduction of the first tarsometatarsal joint dislocation and the dislocated fifth metatarsophalangeal joint was performed. This was followed by open reduction of the dislocated third and fourth metatarsophalangeal joints including reduction of the third and fourth metatarsal heads that were protruding through the plantar foot. Due to the loss of the distal portion of the second metatarsal, an antibiotic spacer was placed to maintain anatomical alignment of the second metatarsal and reduce the risk of infection. The wounds were then closed using Nylon retention sutures and a silastic drain was inserted into the incision over the second metatarsal to facilitate drainage.
Surgery 2: intermediate reconstruction
Five days after initial surgery and following confirmation of negative culture results the patient underwent the second stage of reconstruction. Open reduction and internal fixation of the first tarsometatarsal joint was performed using a bridge plate secured to the medial cuneiform and first metatarsal. The antibiotic spacer previously placed in the second metatarsal was removed. A fibular strut allograft was contoured intraoperatively to match the dimensions of the absent distal second metatarsal and inserted into the defect. The fibular strut allograft was stabilized with a Kirschner wire passed through the second toe and advanced proximally through the second metatarsal. Additional Kirschner wires were used to stabilize the third, fourth, and fifth metatarsophalangeal joints ( Fig. 3 ). This staged approach was important for maintaining structural alignment and preventing infection until the custom 3D-printed implant could be manufactured and implanted.
