Avulsion fractures involving the insertion of the radial extensor at the base of the second and third metacarpals are rare injuries.1-5 Only 7 cases of avulsion fracture of the extensor carpi radialis longus at its insertion over the base of the second metacarpal have been reported previously in the literature.2
This article presents 3 cases of avulsion fractures of the extensor carpi radialis longus insertion that were treated satisfactorily with open reduction and internal fixation using a miniplate and screws.
A 47-year-old man developed painful swelling on the dorsal aspect of the wrist after punching a motor vehicle while intoxicated. On physical examination, active dorsiflexion of the wrist was painful; the pain radiated to the area of the common extensor tendon.
Plain radiographs revealed a radiolucent lesion that was suspected of being a bony defect resulting from a dorsally displaced bone fragment at the base of the second metacarpal bone. Computed tomography (CT) confirmed the dorsally displaced bone fragment originated from the second metacarpal base and was a major fragment of the carpometacarpal joint (Figure).
A 56-year-old woman developed painful swelling on the dorsal aspect of her wrist fell after falling while descending stairs. She could not recall the position of her wrist at the time of injury.
On physical examination, active dorsiflexion of the wrist was painful; and the pain was pronounced at the second metacarpal base. Plain radiographs revealed a dorsally displaced bone fragment at the level of the base of the metacarpal.
A 57-year-old man presented with painful swelling on the dorsal aspect of the wrist following a traffic accident. On physical examination, active dorsiflexion of the wrist was painful. Plain radiographs revealed a dorsally displaced bone fragment at the level of the base of the metacarpal.
The surgical treatment was the same for all 3 patients. A 3-cm longitudinal incision was made on the ulnar side of the first dorsal web space of the hand. In all 3 cases, a dorsally displaced bone fragment resulting from an avulsion fracture of the extensor carpi radialis longus, which occupied >50% of the articular surface of metacarpal base, was identified. However, there was no rupture of the insertion of the extensor carpi radialis longus from the displaced bone fragment. In all three patients, a miniplate (Profile; Leibinger Stryker, Freiburg, Germany) was fixed with 2.3-mm lag screws after anatomical reduction of the displaced bone fragment.
Postoperatively, the wrist was immobilized at 20° of dorsiflexion using a short arm splint for 3 weeks. Motion of the metacarpophalangeal and interphalangeal joints was permitted during this period. Six months postoperatively, maximal power of hand grip and wrist extension was restored in all 3 patients.
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Figure: Case 1. Radiograph showing a radiolucent lesion at the base of the second metacarpal bone suspected of being a bony defect resulting from a displaced bone fragment (A). CT showing the shape and location of the displaced bone fragment (B). Postoperative radiographs showing anatomical restoration of the second carpometacarpal joint (C and D).
In avulsion fractures of the second metacarpal base, DeLee6 reported the mechanism of injury was a force applied to the dorsum of the hand, with the wrist in hyperextension. Contraction of the extensor carpi radialis longus then probably caused displacement of the metacarpal fragment. El-Bacha1 reported the second metacarpal was held rigidly in its position during a forced hyperflexion injury at the level of the wrist because of its constrained osseoligamental environment, preventing dorsal dislocation of the second carpometacarpal complex. Subsequent contraction of the extensor carpi radialis longus tendon resulted in an avulsion of the tendon at its insertion, provided there was sufficient energy during the impact.
The potential complications of avulsion fracture of the second metacarpal base include post-traumatic osteoarthritis of the carpometacarpal joint, weakness of wrist extension and grip, and deformity. Nevertheless, the reported treatment of this injury varies. Crichlow and Hoskinson7 described satisfactory results with nonoperative management in 2 of their 3 cases.
In contrast, Treble and Arif5 recommended open reduction and fixation because of the stabilizing action of the extensor carpi radialis longus during gripping and to avoid the potential rupture of the extensor pollicis longus tendon by the abrasive action of the bone fragment. DeLee6 recommended open reduction and internal fixation to restore the integrity of the joint surface and to replace the insertion of the extensor carpi radialis longus.
The reported methods of fixation of this injury vary. In most of the reported cases, a Kirschner wire has been used. Tsiridis et al8 reported treating an avulsion fracture of the extensor carpi radialis brevis insertion on the third finger with open reduction and internal fixation of the bone fragment using a 2-mm lag screw with simultaneous reattachment of the tendon using a suture anchor.
Avulsion fracture of the base of the second metacarpal should be suspected in patients who have painful, restricted wrist movement following trauma. Radiographic imaging of the avulsed fragment is not always possible, and CT of the hand may be necessary to detect an avulsion fracture. Rigid fixation of these injuries is beneficial and may result in better restoration of function and less morbidity.
- El-Bacha A. The carpometacarpal joints. In: Tubiana R, ed. The Hand. Philadelphia, PA: WB Saunders Co; 1981:158-168.
- Jena D, Giannikas KA, Din R. Avulsion fracture of the extensor carpi radialis longus in a rugby player: a case report. Br J Sports Med. 2001; 35(2):133-135.
- Sadr B, Lalehzarian M. Traumatic avulsion of the tendon of extensor carpi radialis longus. J Hand Surg Am. 1987; 12(6):1035-1037.
- Takami H, Takahashi S, Ando M. Avulsion of the second metacarpal base by the extensor carpi radialis longus. Arch Orthop Trauma Surg. 1998, 118(1-2):109-110.
- Treble N, Arif S. Avulsion fracture of the index metacarpal. J Hand Surg Br. 1987; 12(1):38-39.
- DeLee JC. Avulsion fracture of the base of the second metacarpal by the extensor carpi radialis longus: a case report. J Bone Joint Surg Am. 1979; 61(3):445-446.
- Crichlow TP, Hoskinson J. Avulsion fracture of the index metacarpal base: three case reports. J Hand Surg Br. 1988; 13(2):212-214.
- Tsiridis E, Kohls-Gatzoulis J, Schizas C. Avulsion fracture of the extensor carpi radialis brevis insertion. J Hand Surg Br. 2001; 26(6):596-598.
Drs Kim, Rhee, and Shin are from the Department of Orthopedic Surgery, Chungnam National University College of Medicine, Daejeon, South Korea.
Drs Kim, Rhee, and Shin have no relevant financial relationships to disclose.
Correspondence should be addressed to: Hyun-Dae Shin, MD, Department of Orthopedic Surgery, School of Medicine, Chungnam National University, #640 Daesa-Dong, Jung-Gu, Daejeon 301-040, South Korea.