Extensor tendon ruptures have been reported in up to 8.8% of patients after volar plating and long screws have been implicated. The dihedral dorsal surface of the distal radius hinders accurate screw length determination using standard radiographic views (lateral; pronation and supination). A ‘dorsal tangential’ view has recently been described, but has not been validated.

To validate this view, we mounted a plate-instrumented sawbone onto a jig. Radiographs at different angles were reviewed independently by 11 individuals. Skyline views clearly demonstrated all screw tips, whereas only 69% of screw tips were identifiable on standard views.

With screws 2mm proud of the dorsal surface, skyline views detected 67% of long screws (sensitivity). The best of the standard views achieved only 11% sensitivity. At 4mm long, skyline sensitivity was 85%, compared with 25% for standard views. At 6mm long, 100% of long screws were detected on skylines, but only 50% of 8mm long screws were detected by standard views. Inter and intra-observer variability was 0.97 (p=0.005).

For dorsal screw length determination of the distal radius, the skyline view is superior to standard views. It is simple to perform and its introduction should reduce the incidence of volar plate-related extensor tendon rupture.

Purpose. The undulating pattern of the distal femur is well recognized. Radiographs do not always represent the full extent of the undulations. With recent increasing use of guided growth technique in the distal femur, it is important to define safe zones for screw placement. Method. We performed an anatomical study on 26 cadaveric distal femoral epiphyses, ages 3–18 years. High resolution three-dimensional surface scans were obtained with a laser scanner, and were analyzed to determine the absolute height of the central physeal ridge, and the central physeal ridge height with respect to the highest points medially and laterally. Results. The average height of the central physeal ridge was 5.5mm (range 2.9–9.8mm) with respect to the lowest point on the physis. When normalized to the size of the physis, both the height and surface area of the central physeal ridge decreased with increasing age. The amount that the central peak protruded superior to a line from the medial to lateral physeal edges is shown. In all specimens ages 13 years and older the central peak was below the medial-lateral line, in specimens ages 8–12 years it was no more than 4mm above the line, and in specimens under 8 years it was no more than 8mm above the line. Conclusion. The central physeal ridge is the major structure within the distal femoral physis. In patients 13 years and older the medial-lateral physeal line defines a safe zone one should stay above to avoid screw penetration into the central physis. In patients ages 8–12 years one should stay 4mm above the medial-lateral line, and in patients 8 years and under one should stay 8mm above the line

Increased use of locking volar plates for distal radius fractures led to a number of reports in literature of flexor tendon injuries from impingement and attrition against hardware. Repair of the pronator quadratus is critical in preventing tendon injury. We present a pronator quadratus sparing approach to the distal radius. The senior author has used a pronator quadratus sparing lateral pillar approach for for the past five years. A lateral incision is used over the radial styloid. The first dorsal compartment is released and APL and EPB tendons retracted. The underlying brachio-radialis tendon and insertion fascia is split and the palmar portion elevated off the distal radius with the pronator quadratus as a single contiguous sheet. The distal edge of the pronator quadratus is elevated from the wrist capsule by sharp dissection. The radial artery is protected by the retracted tissue. Repair of the brachio-radialis tendon and insertion fascia is much more robust than that of the pronator quadratus covering the entire plate. Since 2004, the senior author has used the pronator quadratus sparing approach for volar plating of the distal radius, in 183 cases. At last follow-up there were no instances of flexor tendon injury, which was considered to be one of the outcome measures and end-points. There was no impingement in the first dorsal compartment, except in two cases of lateral pillar hardware impingement from additional lateral pillar plate fixation through the same approach. Nine cases had minor persistent superficial radial nerve parasthesia. One case had a superficial wound infection requiring drainage. The repaired pronator quadratus formed a barrier protecting the plate. The infection was aggressively treated and the plate left in situ for three months till fracture union. Cultures from the retrieved plate showed no organisms. Another implant had two of the locking screws back out. The pronator quadratus fascia was tented with an underlying haematoma. The fascia however only showed minimum screw penetration and no flexor tendon injury. Average wrist dorsiflexion was 72 deg and palmar flexion 65 deg. Average pronation was 81 deg and average supination 69 deg. Supination range was slow to recover in younger patients. One explanation could be the tight pronator quadratus repair. Average PRWE and DASH scores were 19. The quadratus sparing approach to the volar distal radius is easy to perform and protects the flexor tendons at the wrist. Cases demonstrated that an intact pronator quadratus can act as an effective barrier to prominent hardware and superficial infection. Supination range may be reduced by this approach due to a tight repair, though a palmar DRUJ capsule contracture may also be an explanation