Carpal malalignment following intra-articular fractures of the distal radius in a working population

Volar Intra-articular Extended Window Approach for Intra-articular Distal Radius Fractures

Distal radius fractures are one of the most common injuries seen globally with increasing use of use of volar plating for surgical treatment. Although it is common to directly visualize the articular surface for most other periarticular fractures, during volar plating of the distal radius the joint is typically not visualized. This is due to concern for carpal instability from disruption of the volar carpal ligaments. When direct visualization of the articular surface is deemed necessary, either to reduce articular fragments or to confirm the quality of reduction, current options include a separate dorsal arthrotomy or arthroscopic assistance. However, biomechanical evidence supports safely performing a volar capsulotomy to visualize the articular surface. We describe the Volar Intra-Articular Extended Window approach, which allows direct visualization of the articular surface through the volar approach to treat distal radius fractures.

Traumatic Volar Carpal Instability Nondissociative: A Case Series

Carpal instability nondissociative (CIND) involves disruption between carpal rows from injury to extrinsic and intrinsic wrist ligaments. CIND traumatic (CINDT) highlights the posttraumatic etiology of some of these cases and has been gaining increasing attention in the literature. We present four cases of CINDT-volar intercalated segmental instability (VISI). We diagnosed two adults with distal radius fractures and two adolescents with Galeazzi fractures, all treated surgically, who developed CINDT-VISI with radiolunate angles greater than 15° at 2 weeks after surgery. One adult had progressive deformity but was asymptomatic at 33 months. The other underwent volar capsular release at 1 year to improve alignment. One adolescent with a fixed deformity required soft tissue releases and temporary pinning to restore alignment at 7 months. We treated the other successfully with early physiotherapy. No patient had radiographic signs of arthritis at 1-2 years. This is the first reported association between Galeazzi fractures and CINDT-VISI. Contrary to existing literature, we report successful outcomes with nonsurgical and delayed nonfusion surgery of CINDT-VISI.

Posttraumatic Carpal Instability Nondissociative

Background  Posttraumatic midcarpal instability nondissociative (CIND) is an exceptional rare condition, therefore the outcome after different treatment options remains unknown. Questions  The purpose of this study was to investigate the different treatment options for posttraumatic CIND. We also describe the different radiological and magnetic resonance imaging (MRI) findings in this patient cohort. Patients and Methods  We present outcomes of 10 patients who developed CIND following acute wrist trauma between 2007 and 2018, 3 with dorsal intercalated segment instability pattern (CIND-DISI) and 7 with volar intercalated segment instability (CIND-VISI) radiographically. Results  Three patients with CIND-VISI had satisfactory outcomes with conservative treatment. Two patients with irreducible CIND-DISI and one with CIND-VISI underwent proximal row carpectomy (PRC), two with reducible CIND-VISI had radiolunate fusion, and two with secondary osteoarthritis had total wrist fusion. All patients with CIND-DISI needed surgery, whereas only four of the seven patients with CIND-VISI needed surgery. On MRI, all three patients with CIND-DISI had rupture of the radiolunate ligament. Conclusions  The data collected in this study may provide the first step toward better understanding of the pathology for this exceptionally rare finding. In CIND-VISI, we have not seen any ligament injury in four patients. Therefore, conservative therapy is more likely to be the first step. In CIND-DISI, we recommend an operative procedure: if detected early, with ligament suture, otherwise by radiolunate fusion, PRC, or total wrist fusion. Level of Evidence  This is a Level IV study.

Carpal Instability Nondissociative Following Acute Wrist Fractures

PURPOSE

Carpal malalignment following intra-articular fractures has been reported in the literature, with no clear description of possible ligamentous injury leading to the radiological appearance. This study presents a series of patients that developed carpal instability nondissociative (CIND) following acute wrist fractures. The mechanism of injury is postulated by using a cadaveric laboratory investigation.

METHOD

Twelve patients with average age of 32 years were identified with CIND, between 2013 and 2018. Ten patients with a normal carpal alignment in the initial postoperative radiographs exhibited CIND-palmar radiographically at different postoperative periods, and 2 patients showed CIND-dorsal in the initial postoperative x-rays. Four cadaveric specimens were used to validate this injury pattern.

RESULTS

In cadaveric dissections, CIND-palmar could be reproduced by applying an axial loading and dorsal shearing force on a wrist with sequential sectioning of dorsal and palmar extrinsic wrist ligaments. For the intra-articular fractures with CIND-dorsal, the cause is likely a result of volar radiocarpal extrinsic ligament injury combined with intra-articular incongruity of the scaphoid fossa. Eight out of the 12 patients had severe wrist pain and underwent additional surgery. Three patients with reducible CIND-palmar had open capsular repair, and 5 patients with fixed nonreducible malalignment were treated with radioscapholunate arthrodesis. At an average follow-up of 2.3 years, pain relief was noted, together with an improvement in grip strength and range of movement. Radiographically, the wrist alignment was corrected and maintained.

CONCLUSIONS

This article highlights the existence of possible concomitant radiocarpal ligament lesions and residual articular incongruity, associated with acute intra-articular fractures and radiocarpal fracture-dislocations, that destabilize the proximal carpal row into a pattern of nondissociative carpal instability. Early detection of this condition may preserve wrist function by capsular repair, whereas cases with fixed deformity and residual joint incongruity may be best managed with a limited radiocarpal arthrodesis.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic IV.

Carpal Alignment: A New Method for Assessment

Background  Carpal alignment may be used as a tool to evaluate fracture reduction in patients with distal radius fractures. However, there is little consensus on how to measure and quantify carpal alignment. Purpose  The aim of this study was to compare the inter- and intraobserver variability of a new perpendicular method with the existing method in fractured and unfractured wrists. Additionally, the normal distribution of carpal alignment in unfractured wrists was investigated. Patients and Methods  Carpal alignment was assessed on lateral plain radiographs using two different methods, one described by Ng and McQueen and another newly proposed method, the perpendicular method. Using the perpendicular method, the observer draws one line along the inner rim of the volar cortex of the radius and one perpendicular line to the center of the capitate. The carpus is aligned when the line along the inner rim transects the center of the capitate. Three examiners measured the carpal alignment in 50 patients with nonfractured and 50 patients with fractured distal radius. Intra- and interobserver variability for both methods were determined. Results  The interobserver coefficient for the perpendicular method was 0.98 and that for the Ng method was 0.86. The intraobserver coefficients for three examiners were 0.89, 0.62, and 0.63, respectively, for the Ng method. For the perpendicular method, the intraobserver variability was 0.96, 0.89, and 0.72, respectively. In patients with unfractured wrists, the mean perpendicular to the center of the capitate was 0.25 mm dorsally. Conclusion  The new proposed method is a reproducible method for measuring carpal alignment with a high inter- and intraclass coefficient. Clinical Relevance  This method of measurement allows for a reproducible technique for measuring carpal alignment.