Results of the Universal 2 Prosthesis in Noninflammatory Osteoarthritic Wrists.

Background/Purpose Many treatment options are available for wrist osteoarthritis, with the objective of decreasing pain and preserving function. In later stages when midcarpal and radiocarpal osteoarthritis occur, two choices remain: total wrist arthrodesis or total wrist arthroplasty. The purpose of this study is to present the short-term functional changes following total wrist arthroplasty with the Universal 2 total wrist system (Integra Life Sciences) in patients with noninflammatory wrist osteoarthritis. Patients and Methods Patients with severe noninflammatory wrist osteoarthritis were assessed preoperatively, 6 and 12 months after surgery using a range of motion, grip strength, pain, and the disabilities of the arm, shoulder, and hand (DASH) score. The additional assessment was performed after 1 year for a range of motion using a biaxial electrogoniometer, grip strength, DASH, and the Michigan hand questionnaire. Results All range of motion directions and grip strength did not change from preoperative values. The DASH score improved from 53 preoperatively to 14 during latest follow-up. Median patients' satisfaction score decreased with approximately 20 points during the last follow-up. Conclusion The relatively good DASH score combined with the partly maintained wrist range of motion indicates that reconstruction with the Universal 2 total wrist prosthesis should be considered in patients with end-stage noninflammatory wrist osteoarthritis. Level of Evidence Level IV, therapeutic study.

Scaphoid screw fixation perpendicular to the fracture plane: Comparing volar and dorsal approaches.

INTRODUCTION: To percutaneously fixate a midwaist scaphoid fracture, both volar and dorsal approaches are considered valid options although they may have different screw insertion angles relative to the scaphoid fracture plane influencing fixation stability. In this virtual simulation study, we investigated the accessibility of placing a screw perpendicularly to the fracture plane in transverse and horizontal oblique scaphoid midwaist fracture models and compared standard volar and dorsal approaches. MATERIAL AND METHODS: Computed tomography scans of 38 healthy wrists were used to obtain virtual 3-dimensional wrist models in flexion and extension. In case the trapezium in volar approach or the distal radius in dorsal approach obstructed the screw axis perpendicular to the fracture plane, an alternative non-obstructed screw axis was chosen as close as possible to the perpendicular axis. The deviation angle between the best possible non-obstructed screw placement and true perpendicular screw placement was quantified. RESULTS: For transverse fractures, the average deviation angle (±standard deviation) was 8° (±5°) in volar approach, and 0° (±0°) in dorsal approach. For horizontal oblique fractures, these angles were 40° (±6°) and 14° (±8°), respectively. DISCUSSION: In our simulations, compared to the volar approach, the dorsal approach provided the most precise screw placement perpendicular to the fracture plane, with the largest differences for horizontal oblique fractures. When taken in addition to screw purchase, thread engagement and protrusion risk, information about screw orientation may help surgeons in deciding between percutaneous approaches in scaphoid surgery on which there is currently no consensus. LEVEL OF EVIDENCE: N/A.

Comparison of activities of daily living after proximal row carpectomy or wrist four-corner fusion.

Proximal row carpectomy and four-corner fusion are commonly used in the patients with scaphoid nonunion advanced collapse or scapholunate advanced collapse. We compared activities of daily living of the 24 patients after proximal row carpectomy with 24 patients with four-corner fusion procedures using the modified Sollerman hand function test and Michigan Hand Questionnaire. Most tasks were performed significantly quicker by the patients after proximal row carpectomy. The patients after proximal row carpectomy reported better function during activities of daily living. LEVEL OF EVIDENCE: Level III, Therapeutic Study.

Comparing radial styloid size between osteoarthritic and healthy wrists: a pathoanatomical three-dimensional study.

Radial styloid pointing due to spur formation is considered an early sign of osteoarthritis, but is sometimes difficult to distinguish from normal anatomic variation. In this pathoanatomical study we used three-dimensional imaging techniques to evaluate quantitatively whether the styloid size is larger in wrists with scaphoid non-union than in healthy wrists. We compared these findings with duration of the non-union and with the scaphoid non-union advanced collapse classification, which was based on radiographic assessment of the general level of wrist osteoarthritis. In 31 patients, the injured styloid was consistently larger than the contralateral healthy styloid. In 74% of the patients this pathoanatomical difference (maximum 5 mm) exceeded anatomical left-to-right variation in styloid size (maximum 2 mm), indicating significant pointing. Increased styloid pointing was associated with older non-unions, and with more severe osteoarthritis. Three-dimensional styloid pointing analysis is an objective method to assess osteoarthritic progression. Combining traditional qualitative evaluation and quantitative measurements may improve the classification of wrist osteoarthritis. LEVEL OF EVIDENCE: IV.