Simultaneous Arthrodesis of Proximal and Distal Interphalangeal Joints in Hand Trauma

Our patient presented with palmar-based injuries to the ulnar three digits of his dominant hand—there were multiple transverse lacerations with multilevel disruptions to the flexors and digital nerves ([Fig. 1]). There were comminuted, intra-articular fractures of the proximal and middle phalanges of the ulnar two digits ([Fig. 2]). Intraoperatively, devitalized palmar skin, together with flexor tendon substance from the proximal extent of the wound to the distal extent of the wound, was excised. Arthrodesis of both interphalangeal joints and flap coverage of the palmar defect were performed.

Fig. 1 Injury photograph and radiograph.

Fig. 2 The 6 months review: Range of motion of digits and radiograph showing healed arthrodesis.

Six months postoperatively, he reported painless motion of the affected digits ([Fig. 2]); he had returned to work 3 months after the injury. Being an ethnic Indian, the ulnar two digits are also useful when he eats with his hand. Active flexion of 70 and 65 degrees at the metacarpophalangeal joints of the ring and little fingers, respectively, was achieved ([Fig. 2]). The grip strength of the right hand was 20 kg, while that of the contralateral hand was 48 kg. The arthrodesed joints were healed on radiographs ([Fig. 2]).

Spontaneous ankylosis of both interphalangeal joints of a finger has been described with preservation of metacarpophalangeal joint mobility[1]—this was the rationale behind our management. Flexor tendon reconstruction in the setting of intra-articular, comminuted phalangeal fractures would have resulted in a stiff, painful finger, with likely longer rehabilitation period. While amputation of the digits was a consideration, we decided on a salvage procedure for a few reasons—involvement of the dominant hand, the third of grip strength that the ulnar two digits confer to the hand[2] [3] and good perfusion of the fingers with partially intact sensation despite extensive volar injuries. Therefore, we decided on primary arthrodesis of the interphalangeal joints, and excision of the flexor tendons.

In inflammatory conditions, where both interphalangeal joints are fused, the flexor mechanism is still intact and contributes to metacarpophalangeal joint flexion. Our case demonstrates that, in the complete absence of the extrinsic flexor tendons, active flexion of 65 to 70 degrees were achievable in the ulnar digits' metacarpophalangeal joints—this is consistent with Ketchum et al finding of intrinsics' contribution to metacarpophalangeal joint motion as 73%.[4]

In the setting of hand trauma with extensive flexor tendon and intra-articular osseous injuries, a similar approach may be considered—arthrodesis of both interphalangeal joints and depending on the intrinsics for metacarpophalangeal joint motion.

• References

• 1 Nalebuff EA. Surgery of psoriatic arthritis of the hand. Hand Clin 1996; 12 (3) 603-614
• 2 Arnet U, Muzykewicz DA, Fridén J, Lieber RL. Intrinsic hand muscle function, part 1: creating a functional grasp. J Hand Surg Am 2013; 38 (11) 2093-2099
• 3 Cha SM, Shin HD, Kim KC, Park JW. Comparison of grip strength among 6 grip methods. J Hand Surg Am 2014; 39 (11) 2277-2284
• 4 Ketchum LD, Thompson D, Pocock G, Wallingford D. A clinical study of forces generated by the intrinsic muscles of the index finger and the extrinsic flexor and extensor muscles of the hand. J Hand Surg Am 1978; 3 (6) 571-578