Trentadue, Taylor P.

Abstract Background In predynamic or dynamic scapholunate (SL) instability, standard diagnostic imaging may not identify SL interosseous ligament (SLIL) injury, leading to delayed detection and intervention. This study describes the use of four-dimensional computed tomography (4DCT) in identifying early SLIL injury and following injured wrists to 1-year postoperatively. Description of Technique 4DCT acquires a series of three-dimensional volume data with high temporal resolution (66 ms). 4DCT-derived arthrokinematic data can be used as biomarkers of ligament integrity. Patients and Methods This study presents the use of 4DCT in a two-participant case series to assess changes in arthrokinematics following unilateral SLIL injury preoperatively and 1-year postoperatively. Patients were treated with volar ligament repair with volar capsulodesis and arthroscopic dorsal capsulodesis. Arthrokinematics were compared between uninjured, preoperative injured, and postoperative injured (repaired) wrists. Results 4DCT detected changes in interosseous distances during flexion-extension and radioulnar deviation. Generally, radioscaphoid joint distances were greatest in the uninjured wrist during flexion-extension and radioulnar deviation, and SL interval distances were smallest in the uninjured wrist during flexion-extension and radioulnar deviation. Conclusion 4DCT provides insight into carpal arthrokinematics during motion. Distances between the radioscaphoid joint and SL interval can be displayed as proximity maps or as simplified descriptive statistics to facilitate comparisons between wrists and time points. These data offer insight into areas of concern for decreased interosseous distance and increased intercarpal diastasis. This method may allow surgeons to assess whether (1) injury can be visualized during motion, (2) surgery repaired the injury, and (3) surgery restored normal carpal motion. Level of Evidence Level IV, Case series.

Background: The aim of this study is to compare clinical and radiographic outcomes of open reduction and internal fixation versus closed reduction and percutaneous pinning of metacarpal fractures in relation to anatomic and surgical variables. Methods: Electronic medical records at two institutions were reviewed for patients who underwent surgical intervention for metacarpal fractures. Data were collected from those who underwent reduction and internal fixation with either plates or Kirschner wires (K-wires). Inclusion criteria included minimum postoperative follow-up of 60 days and age 18 years or older. Exclusion criteria included insufficient radiographic data, previously attempted closed reduction with immobilization, pathologic fracture mechanism, history of previous trauma or surgery to the affected bone, and fixation technique other than plate or K-wire. Results: We reviewed data for patients treated over a 22-year time period. Ultimately, 81 metacarpal shaft and neck fractures in 60 patients met inclusion criteria. Among all metacarpal fractures, complications were present in 39 (48.1%) cases. There were no significant associations between complication prevalence and hardware type. Revision surgery was required in 11 (13.6%) patients; there were no significant associations between revision procedures and hardware type. Postoperatively, all patients with imaging data had radiograph follow-up to assess union status. There was no significant association between time to union and hardware type. Conclusions: Outcomes showed no significant difference between plate and pin fixation for metacarpal shaft and neck fractures. These findings suggest that surgeons may have flexibility to decide on the type of operative intervention while considering patient-specific factors, such as the need for early mobilization.

Background: Radioscapholunate (RSL) fusion is performed for painful radiocarpal arthritis that is typically posttraumatic or inflammatory in nature. The purpose of this study was to determine whether patients with inflammatory conditions undergoing RSL fusion had comparable outcomes as those with posttraumatic arthritis and to determine factors impacting union. Methods: This was a retrospective review of all RSL fusions over a 25-year period. Demographic information, wrist range of motion, postoperative complications, and surgical technique, including presence or absence of resection of distal scaphoid pole, data were collected. Radiographs were examined for evidence of healing of the RSL fusion site as well as development of midcarpal arthritis. Results: Fifty-six patients underwent RSL fusion. Eight patients required revision of radiocarpal arthrodesis for painful nonunion. The fusion rate was 85.7%, and median 25 th to 75th percentile (time to healing was 4.0 3.2-5.2) months. There were no differences in time to or rate of union by inflammatory arthropathy status. Grip strength increased significantly and pain decreased significantly with surgery. Union rate was 90% with the use of K-wires, screws, or staples, which was significantly greater than plates, fusion cups, or multiple implant types. The use of autologous bone graft significantly decreased the rate of nonunion and significantly decreased time to union by 3 months compared to allograft alone. Extension was significantly improved with scaphoid distal pole resection versus without distal scaphoid pole resection. Conclusions: Radioscapholunate (RSL) fusion is an effective treatment for radiocarpal arthritis but has high nonunion rates. Fixation with K-wires, screws, or staples and use of autograft confers improved union rate.