Surgical Strategy and Techniques for Low-Profile Dorsal Plating in Treating Dorsally Displaced Unstable Distal Radius Fractures

Abstract

Background The low-profile dorsal locking plating (DLP) technique is useful for treating dorsally comminuted intra-articular distal radius fractures; however, due to the complications associated with DLP, the technique is not widely used. Methods A retrospective review of 24 consecutive cases treated with DLP were done. Results All cases were classified into two types by surgical strategy according to the fracture pattern. In type 1, there is a volar fracture line distal to the watershed line in the dorsally displaced fragment, and this type is treated by H-framed DLP. In type 2, the displaced dorsal die-punch fragment is associated with a minimally displaced styloid shearing fracture or a transverse volar fracture line. We found that the die-punch fragment was reduced by the buttress effect of small l-shaped DLP after stabilization of the styloid shearing for the volar segment by cannulated screws from radial styloid processes. At 6 months after surgery, outcomes were good or excellent based on the modified Mayo wrist scores with no serious complications except one case. The mean range of motion of each type was as follows: the palmar flexion was 50, 65 degrees, dorsiflexion was 70, 75 degrees, supination was 85, 85 degrees, and pronation was 80, 80 degrees; in type 1 and 2, respectively. Conclusion DLP is a useful technique for the treatment of selected cases of dorsally displaced, comminuted intra-articular fractures of the distal radius with careful soft tissue coverage.

Keywords: dorsally displaced distal radius fractures; fracture type; indication and clinical results; low-profile dorsal locking plates; surgical strategy and technique.

Fig. 1

Schematic drawing of the type 1 fracture. This dorsal transition of both radial and ulnar columns is caused by dorsal shearing force and compression force, and is classified as follows. (A) A dorsal Barton fracture with no volar fracture line was observed in one case. The dorsal transition type of that volar fracture line is distal to the watershed line and is often accompanied by (B) central depression of the joint surface (three cases) or (C) the dorsal roof and rim fragments (five cases), which creates instability. RC, radial column; UC, ulnar column.

Fig. 2

Schematic drawing of the type 2 fracture. This type includes the DUC (dorsal die-punch) fragment in all 15 cases, accompanied by a minimally displaced SSF (in 13 cases) or TVFL (in 6 cases). DUC, dorsoulnar column; SSF, styloid shearing fragment; TVFL, transverse volar fracture line.

Fig. 3

A dorsal approach to soft tissue treatment before and after dorsal plating. We devised procedures to prepare and close the extensor retinaculum and periosteum to avoid direct contact between the plate and extensor tendon, especially at the distal half of the DLP as shown. The reliable and stable closure was made by making the following four flaps (a, b, c, and p). (A) A longitudinal incision was made 5 to 10 mm ulnar to the Lister tubercle in the distal radius region. Dissection was performed down to the extensor retinaculum. The fourth compartment was opened by cutting the extensor retinaculum in a zig-zag fashion to make three flaps (a, b, and c). (B) The EDC was displaced radially and the gliding floor of fourth compartment and fifth compartment wrist extensors (zone-1; ulnar side) were subperiosteally elevated ulnarly. If radial column exposure is necessary for the treatment of type 1 fracture, the retinaculum of the third or second extensor compartment is opened, elevating the EPL. The third or second compartment (zone-2; radial side) is subperiosteally elevated radially for dorsal plating. The dorsal interosseous nerve may be cutoff for pain reduction. (C and D) Our devised points at the time of wound closure include steps as follows. Removal of tuberculum listeri is rarely necessary. The previously separated flaps of the extensor retinaculum (a, c) were sutured to the ulnar side of the periosteal flap to cover the distal half of the plate. The distal half of the dorsal plate where soft tissue coverage is important to prevent tendon irritation. (E) Another flap of the extensor retinaculum (b) was repaired adjacent to the radiocarpal joint level to prevent the bowstring of extensor tendons. EPL can be used on the outside of extensor retinaculum. The incision is closed. DLP, dorsal locking plating; EDC, extensor digitorum communis; EPL, extensor pollicis longus.

Fig. 4

Schematic drawing of the surgical strategy of reduction and fixation in the displaced distal radius in the type 1 fracture. (A) Yellow arrows indicate the order of correction of the roof fragment by buttress effect. Red arrows indicate the pathway to elevate central depression of the articular surface. Central depression of the joint surface was elevated through fracture gap at the dorsal side as shown by radiograph during surgery. (B) The left figure shows the order of H-framed plate bending to adapt the plate for correction and fixation of the displaced fragments. (C) The final procedure to obtain precise joint correction by lengthening the radius through oblong holes and positioning the screw in a locking plate.

Fig. 5

Schematic drawing of the surgical strategy of reduction and fixation of the displaced distal radius in the type 2 fracture. (A) Radial styloid fragments or crossing fracture lines at the volar surface were stabilized using a percutaneous cannulated screw. (B) Buttress reduction of the dorsal die-punch fragment through a limited DUC opening. DUC, dorsoulnar column.