Take-Home Points
- Patients sustaining DRFs commonly have associated ligament injuries and chondral damage as well.
- Many of these associated injuries do not seem to affect outcomes up to 1 year after surgery.
- Plain radiographs have a 74% sensitivity and 73% specificity for detecting intra-articular fractures.
- ”Minor” injuries identified incidentally by arthroscopy during fixation of DRFs may not require dedicated treatment.
- The optimal treatment for high-grade ligament or chondral injuries in patients with DRFs remains incompletely understood.
Distal radius fracture (DRF) is one of the most common upper extremity injuries, with up to 20% to 50% requiring surgical fixation.1 With increasing use of wrist arthroscopy to assist in managing these fractures,2-6 it has become easier to accurately assess concomitant wrist ligament injuries. Reported injury rates are 18% to 86% for the scapholunate interosseous ligament (SLIL),7,8 5% to 29% for the lunotriquetral ligament (LTL),8,9 and 17% to 60% for the triangular fibrocartilage complex (TFCC).10,11 Reported chondral injury rates range from 18% to 60%.7,9,12 Despite the common occurrence of these injuries, it is unclear how they affect outcomes and how aggressively they should be treated when detected during fracture surgery.
As the use of arthroscopy in DRF management becomes more common, surgeons often must decide how to treat ligamentous/chondral injuries incidentally discovered during surgery. To date, only 1 study prospectively evaluated how these injuries affect DRF outcomes,8 though it did not use a validated, patient-based outcome measure.
We conducted a study to address a common clinical scenario: When arthroscopy is used to assist with intra-articular reduction during DRF fixation, how should the surgeon respond to incidentally identified ligament and chondral injuries? Specifically, we wanted to address 3 questions: What is the overall incidence of SLIL, TFCC, and chondral surface injuries in patients undergoing operative fracture fixation? On initial injury films, do any radiographic parameters predict specific soft-tissue injuries or ultimate functional outcomes? Do wrist ligament and chondral injuries affect patient-rated outcomes (disability, pain) and objective measures (range of motion [ROM], grip strength, pinch strength) up to 1 year after fracture surgery?
Materials and Methods
Patient Selection/Population
This observational, prognostic study was approved by our Institutional Review Board. Inclusion criteria were age over 18 years, isolated acute operatively treated DRF (surgery within 14 days of injury), and informed consent. All patients were treated by the same surgeon. Exclusion criteria were open DRF, dorsal shear pattern, fractures requiring dorsal arthrotomy for reduction because of significant intra-articular damage, prior ipsilateral DRF, and prior SLIL or TFCC injury.
Surgery was indicated according to general radiographic parameters as measured on postreduction films: radial height, <8 mm; radial inclination, <15°; positive ulnar variance, >3 mm, or 3 mm more than contralateral side; dorsal tilt, >10°; and volar tilt, >15°. With these parameters within acceptable limits, surgery was also indicated when fractures were deemed unstable and likely to displace because of dorsal tilt >20°, dorsal comminution, intra-articular step-off of ≥2 mm on the posterior-anterior (PA) film, associated ulnar fracture, and age >60 years.13Over a 2-year period, 42 patients (12 male, 30 female) met the inclusion criteria and were enrolled in the study. The dominant arm was affected in 17 patients (40%). Mean (SD) age at time of injury was 56.6 (16.4) years (median, 54 years; range, 20-85 years).
Operative Technique
During surgery, damage to the SLIL, the TFCC, and chondral surfaces (scaphoid, lunate, scaphoid fossa, lunate fossa) and to the intra-articular extension of the DRF was assessed and recorded. Wrist arthroscopy was performed with the 3, 4 portal as the primary portal. When significant damage to the TFCC warranted débridement, the 6R (radial) portal was used as an accessory portal. As a midcarpal portal was not used for SLIL assessment, we used a novel classification system: 0 = no injury, normal-appearing ligament without hemorrhage and smooth transition from scaphoid to lunate surface except for slight concave indentation at the ligament; 1 = attenuation, no visible tear with convex shape of ligament with or without hemorrhage; 2 = partial tear with or without step-off at junction between scaphoid and lunate, but 2.7-mm arthroscope cannot “drive through” to midcarpal joint; and 3 = complete tear with positive “drive-through” sign. TFCC injuries were classified according to the system described by Palmer14: Avulsions were central (1A), ulnar (1B), distal (1C), or radial (1D). The trampoline test was performed through a 6R portal by using a probe to evaluate ligament tension/laxity. In some cases, a 6R portal was deemed unnecessary, and a modified trampoline test was performed—tension/laxity/displacement was evaluated by manually palpating at the fovea and observing TFCC motion with the arthroscope. When appropriate, the TFCC was débrided with a shaver through the 6R portal. In cases of significant instability at the SLIL interval, two 0.062-inch K-wires were placed percutaneously through the scaphoid and lunate, and one was placed from the scaphoid to the capitate.