Case of Enchondroma of Left 4th Metacarpal of Hand Treated with Excision and Bone Grafting with Left 2nd Metatarsal of Foot: A Rare Case Report

Abstract

Introduction: Enchondroma of the hand is a common lesion with a recurrence rate of up to 13.3% after curettage and bone grafting. When hand enchondroma is suspected, less common conditions, such as multiple enchondromatosis syndromes and benign and malignant lesions, should be ruled out. Pathologic fractures often occur. Post-operative complications are typically joint stiffness and soft-tissue-related deformities, whereas recurrence and malignant degeneration of solitary lesions are much less common. Most patients return to full function after surgery.

Case report: We present a case of enchondroma of the fourth metacarpal in a 38-year-old female who has a history of a mishap that occurred 3 months ago. Radiographic evaluation was done by X-ray and magnetic resonance imaging which revealed a well-marginated lytic lesion in the head, neck, and distal phalanx of the left 4th finger and significant cortical destruction, completely replacing the bone in the affected region. There was no involvement of the metacarpophalangeal joint. The patient was planned for excision of the 4th metacarpal and bone grafting, plating and K-wire fixation with the 2nd metatarsal bone graft. Post-operatively below elbow slab was given for the patient to promote wound healing and fracture healing for 4 weeks. After 2 weeks of surgery gradual wrist movements were started. Follow-up radiographs were taken every 4 weeks to check for union of bone. Upon radiographic union, finger movement was gradually started as tolerated by the patient. After 8 weeks of surgery radiograph showed a union of bone and K-wires were removed under local anesthesia and full finger movement was started. The patient achieved full finger movement in 12 weeks post-operatively.

Conclusion: Enchondroma of the hand has a non-specific clinical presentation and a variable radiographic appearance. A patient-specific differential diagnosis should be established because various benign and malignant processes can mimic enchondroma radiographically. Nevertheless, controversy surrounds the roles of post-curettage surgical adjuncts, immediate versus delayed grafting and fixation, and void management. Surgical management, involving lesion excision and autograft reconstruction, demonstrated excellent results, enabling complete healing and restoration of function within 20 weeks post-operatively. This approach highlights the efficacy of precise surgical techniques combined with structured post-operative rehabilitation in achieving optimal patient outcomes.

Keywords: Enchondroma; autograft; bone grafting; plating.

Figure 1

(a and b) Pre-operative X-ray showing well-marginated lytic lesion in the head, neck, and distal phalanx of the left 4th finger.

Figure 2

(a-c) Magnetic resonance imaging which revealed a well-marginated lytic lesion in the head, neck, and distal phalanx of the left 4th finger and significant cortical destruction, completely replacing the bone in the affected region. Extensive adjacent soft tissue edema involving the flexor and extensor tendons of the 4th finger.

Figure 3

(a- d) A 5 cm incision was taken from the base of the left 2nd metatarsal extending to the head. Superficial and deep dissection was done. 2nd metatarsal was exposed and cut just distal from the base with the help of a saw. The metatarsal graft was harvested along with the volar plate, medial, and lateral ligament.

Figure 4

(a- d) A 5 cm incision was taken over the left 4th metacarpal from the base extending up to the 4th metacarpophalangeal joint. Superficial and deep dissection was done.

Figure 5

(a and b) Lesion was excised from a shaft of the 4th metacarpal 1cm proximal to enchondroma with the help of a C-arm. Metacarpal was excised.

Figure 6

(a-d) Post-operative X-ray of left foot after metatarsal removal and X-ray of left hand showing 5-hole plated fixed with appropriate size screws and 1.2 mm K-wire had been passed from head of 5th metacarpal toward head of a 4th metacarpal and another 1.2 mm K-wire had been passed from distal phalanx to head of 4th metacarpal.

Figure 7

(a and b) Post-operative X-ray at 3 months showing union of 4th metacarpal.

Figure 8

(a,b and c) clinical pictures taken at 3 months post-operatively showing healed surgical site and full finger movement of the patient.

Figure 9

Histopathology sample showing features suggestive of enchondroma.