Literature Review

There are several published case series reporting a large percentage of overall good to excellent results using intrafocal pinning. Epinette and associates reported 83% good and excellent results in 70 cases, including elderly patients and fractures with undisplaced intra-articular extension.¹³ Docquier and colleagues also reported a high percentage of good and excellent clinical and radiographic results using this technique for articular and extra-articular fractures.¹⁴ Peyroux and coworkers reported the outcome of 159 cases (81% extra-articular) with 93% good and excellent clinical results.¹⁵

Dowdy and associates retrospectively reviewed the results of 17 patients treated with intrafocal pinning.¹⁶ All K-wires were cut below the skin, and the injured area was immobilized for 6 weeks. Sixteen of 17 patients were pleased with their outcomes. The average visual analog score on the pain scale was 0.44/10, and function was 8.6/10. There was a trend for older osteopenic patients to lose their postoperative reduction, but this was not statistically significant.¹⁶ Patients aged 65 and older also had significantly less restoration of volar tilt than those younger than 65 years of age (P = .04). Dowdy recommended that Kapandji pinning alone should be avoided in patients with severe osteopenia.

In the largest series published to date, Nonnenmacher and coworkers reported the results of 350 intra-articular and extra-articular distal radius fractures in patients aged 12 to 89 treated with this technique.¹⁷ They used three intrafocal pins, which were buried below the skin and removed at 6 weeks. Plaster immobilization was not used, and patients were allowed to begin range of motion postoperatively. The subjective results were good and excellent in 90% of patients, and functional outcomes were reported as good and excellent in 99%. No patients reported poor subjective or functional outcomes. The radiologic results were also evaluated as 93% good to very good, 6% average, and 1% poor.¹⁷

The experience with intrafocal pinning in older patients has grown in recent years. Greating and coworkers reported on the results of 24 fractures with minimal intra-articular involvement in patients aged 16 to 94.¹⁸ They utilized immobilization in patients for 6 weeks after the surgery. In 13 fractures, the clinical outcomes were excellent in 7, good in 4, and fair in 2 based on the Mayo wrist score. The two fair results were in patients younger than age 65. They also report good and excellent radiologic results (using Sarmiento and colleagues’ criteria²²) in 79% of patients younger than 65 and in 60% of patients older than 65. They concluded that this technique provides acceptable clinical results in elderly patients despite some loss of reduction after pinning.

Trumble and coworkers published a review of their experience with intrafocal pinning supplemented with external fixation.¹⁹ They reviewed 61 patients with either intrafocal pinning alone or in combination with external fixation. They included fractures with undisplaced intra-articular extension and all age groups. There were 96% good to excellent results in young patients (<55 years) with displaced extra-articular distal radius fractures (minimal comminution) treated with intrafocal pin fixation alone. In patients older than 55 years of age, they reported 94% good to excellent results in patients who received supplemental external fixation and they also reported that range of motion, grip strength, and pain relief were significantly better when external fixation was used in this age group, even when only one cortex demonstrated comminution. Their final recommendation was that older patients, or younger patients with involvement of more than two surfaces of the radial metaphysis (or >50% of the metaphyseal diameter), require external fixation in addition to percutaneous pin fixation for optimal results.¹⁹

In a retrospective review by Board and associates comparing closed reduction and casting to intrafocal wiring in patients older than 55 years, it was found that functional results were good to excellent in 19 of 23 patients who received intrafocal pinning versus 12 of 23 who received plaster alone, supporting the use of this technique in older patients.²⁰

Hollevoet recently published a study assessing anterior fracture displacement in Colles’ fractures after intrafocal pinning in women older than age 59 years (without supplemental external fixation).²¹ It was demonstrated that the intrafocal pins were not sufficient to prevent anterior fracture displacement in almost one third of patients. Five weeks after fracture, 36 of 89 (40.4%) patients had more than 20 degrees of palmar shift or tilt or more than 10 degrees of dorsal angulation; 37 patients (41.6%) had more than 2 mm of ulnar-positive variance; and 6 (6.7%) had more than 5 mm of ulnar-positive variance. The clinical implications of this displacement were not discussed. They concluded that intrafocal wiring of Colles’ fractures in elderly, osteoporotic patients may not be sufficient to prevent anterior fracture displacement.²¹

Indications

Intrafocal pinning is indicated for unstable displaced distal radius fractures in which it is not possible to obtain or maintain a reduction with cast immobilization (Fig. 17-1). The ideal candidate for Kapandji pinning is a younger patient with good quality bone. Ideally, the fracture should be extra-articular with minimal comminution and easily reducible with closed methods. Since the original description of this technique,¹¹ the indications have expanded to include older patients,¹³ fractures with undisplaced intra-articular extension,¹³ and fractures with multiple fragments.¹²

FIGURE 17-1 A 46-year-old woman slipped on ice, fell onto her outstretched hand, and sustained an extra-articular distal radius fracture. Pre-reduction (A) and post-reduction (B) anteroposterior and lateral radiographs.

This technique works best in the acute setting while the fracture fragment is still mobile. If the procedure is delayed, this technique is not contraindicated but it may become more difficult or impossible to successfully manipulate the distal fragment into the correct position with closed methods.

Contraindications

The intrafocal technique is contraindicated in fractures with significant intra-articular displacement and/or volar cortical comminution.^8,18,23 It is also contraindicated if a reduction cannot be achieved by closed means.^18,23 Relative contraindications to this technique are poor bone quality and osteoporosis.¹⁷ We also avoid intrafocal pinning in patients with severe osteopenia, marked dorsal radial comminution, an associated ipsilateral distal metadiaphyseal ulna fracture, and both volar and dorsal comminution.¹⁶ In these circumstances, the Kapandji pins may require supplementation with an external fixator.^16,24

Surgical Technique

At our institution, this procedure is performed with the patient under general anesthesia or with a brachial plexus block with tourniquet control. The patient is positioned supine, with the affected extremity suspended from sterile finger traps with 10 to 15 pounds of countertraction. Fluoroscopy is available to ensure that adequate anteroposterior and lateral images can be obtained during the procedure.

Attention is directed toward first correcting the dorsal tilt. Two 0.062-inch K-wires are percutaneously inserted into the dorsal aspect of the wrist. A dorsal radial pin is inserted between the third and fourth extensor compartments, and a dorsal ulnar pin is inserted between the fourth and fifth extensor compartments. The K-wires are then manually advanced through the dorsal cortex and into the fracture site just short of the volar cortex. The image intensifier facilitates locating the fracture site. These two wires are then levered distally under image control to correct the dorsal tilt (Fig. 17-2). A 0.062-inch K-wire is then inserted percutaneously on the radial aspect of the wrist, between the first and second dorsal compartments, and manually advanced into the fracture site. The K-wire is then levered distally to restore the radial inclination (Fig. 17-3). When an adequate reduction is achieved fluoroscopically, the wires are then advanced through the intact volar and ulnar cortex using a powered wire driver. The final reduction and pin position should then be confirmed radiographically (Fig. 17-4A). Excessive pin protrusion through intact cortex should be avoided to prevent impingement on adjacent structures. The K-wires can then be cut just below the skin but superficial to the extensor tendons to avoid rupture. Alternatively the K-wires can be bent over and cut above the skin. The arm is immobilized in a short arm cast for 6 weeks (see Fig. 17-4B). Early digital motion and forearm rotation are encouraged. At 6 weeks, the K-wires are removed under local anesthetic in the clinic. Range of motion exercises of the wrist are then initiated and supervised by a hand therapist (see Fig. 17-4C).

FIGURE 17-2 Restoration of dorsal angulation.

FIGURE 17-3 Restoration of radial inclination.

FIGURE 17-4 Same case as in Figure 17-1. A, Postoperative anteroposterior and lateral radiographs. B, Radiographic appearance at 7 weeks: fracture is healed and pins ready for removal. C, Anteroposterior and lateral radiographs at 3 months after the injury.

Clinical Pearls

When performing intrafocal pinning for distal radius fractures, the K-wires should be inserted through the skin, just distal to the fracture so that when the wire is tilted distally, as the fracture is reduced, the skin will not be tethered. During the reduction process, avoid bending the K-wire by pushing on the wire immediately adjacent to the skin. In addition, the reduction process should be monitored with live fluoroscopy to avoid either undercorrecting or overcorrecting the displacement.

Potential Pitfalls

Although the procedure is not technically demanding, there are some potential pitfalls to avoid. When advancing the K-wires into the volar cortex, one must ensure that the K-wire does not enter the volar compartment because this may cause nerve or tendon irritation. It is also possible to over-reduce the fracture, cause volar translation of the fragment, or displace an intra-articular fracture. As mentioned previously, these pitfalls can be avoided by monitoring the reduction process with fluoroscopy. One should also consider supplementing intrafocal pinning with an external fixator if the patient is older than 55 years of age or if there is comminution involving more than two surfaces of the radial metaphysis (or >50% of the metaphyseal diameter)^19,24 (Fig. 17-5).

FIGURE 17-5 A 22-year-old man fell while snowboarding and sustained an extra-articular distal radius fracture with volar comminution. A, Preoperative anteroposterior and lateral radiographs. B, Postoperative anteroposterior and lateral radiographs showing Kapandji pins and external fixation. C, Healed fracture with Kapandji pins and external fixator removed. Patient regained full motion at 3 months.

Controversies

There are many modifications of the intrafocal pinning technique. Some prefer to leave the K-wires above the skin for ease of removal, whereas others prefer to bury them below the skin, to reduce the risk of infection. Some insert the K-wire percutaneously, whereas others believe strongly that a small incision should be made to ensure all essential neurovascular and tendinous structures can be retracted aside. The other controversial aspect is postoperative immobilization. Although Kapandji’s original description did not include postoperative immobilization, in more recent reports the fractures are usually immobilized to prevent displacement, particularly if using this technique for more challenging cases.

Salvage Procedures

The benefit of this technique is that it does not preclude the use of more traditional techniques such as open reduction and internal fixation. If the fracture cannot be reduced or if the fragments are over-reduced or displaced during the reduction procedure, one can always perform an open reduction and internal fixation.

Personal Results

We reviewed the experience with extra-articular distal radius fractures at the Hand and Upper Limb Center in London, Ontario, from June 1997 to June 2004. Twenty-eight patients were treated with the intrafocal pinning technique described by Kapandji and were available for 1-year follow-up. All patients were followed at 6 weeks, 3 months, 6 months, and 1 year. At each visit, objective clinical data (range of motion and grip strength), radiographs, Disabilities of the Arm, Shoulder, and Hand (DASH) scores, Patient-Rated Wrist Evaluation (PRWE) scores, and SF-36 scores were obtained.

There were 5 men and 23 women in this group. The average age was 46.9 ± 15.3 years (range 18 to 72). One patient was involved in a workers’ compensation claim. Seventeen patients were treated with Kapandji pinning and cast immobilization alone, 9 patients were treated with Kapandji pinning plus external fixation, and 2 patients had an open reduction and internal fixation supplemented with intrafocal pinning. Of the nine external fixators in this series, eight were used in patients older than the age of 55. There were 3 patients older than the age of 55 who were treated with Kapandji pinning and casting alone.

Complications

The most common complications reported with Kapandji pinning are loss of fracture reduction, extensor tendon rupture, radial sensory nerve irritation, and reflex sympathetic dystrophy.⁸ Early pin removal, fracture displacement after pinning, and infection are also described.⁸ In the largest series on Kapandji pinning,¹⁷ complications reported include 1 patient with distal radioulnar joint instability, reflex sympathetic dystrophy (8%), need for early pin removal (7%), radial sensory nerve irritation (6%), ulnar neuropathy of the wrist (n = 1), extensor tendinitis (2%), and some displacement of fracture fragments after pinning (14%). It was found that secondary displacement of the fracture did not usually affect the final clinical result.¹⁷

In our experience, loss of fracture reduction over time was uncommon, perhaps because all fractures in older patients were supplemented with external fixation. There were four complications in our cohort. There was one patient with reflex sympathetic dystrophy (requiring a stellate ganglion block), one extensor pollicis longus rupture (requiring surgical repair), and one patient requiring early pin removal because of volar migration of the K-wire. In addition, there was one infected nonunion, which occurred despite the wires being buried below the skin.