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activities. This load shift will pose the ulnohumeral joint and especially the lateral part at higher risk for degeneration. Whether ulnohumeral degeneration is delayed due to a smaller load shift in proximal radial osteotomy compared to radial head resection does not exclude that a previous healthy ulnohumeral articulation is now prone to developing osteoarthritis. Furthermore, Hackl et al. [2] showed that valgus stress will be less after a 2.5-mm shortening osteotomy compared to radial head resection, likely reducing the chance of tardy ulnar collateral ligament (UCL), subsequent valgus instability and medial elbow pain complaints. However, it remains a fact that valgus strain will increase and may cause tardy UCL elongation and elbow valgisation in the long run. Subsequently, this further increases medial ulnohumeral loading on top of the initial load shift from the radiocapitellar joint to the ulnohumeral joint. Extending the osteoarthritis from a unicompartmental problem to generalised osteoarthritis of the elbow creates an even more difficult to treat condition for which eventually total elbow prosthesis may be necessary. Second, radial head fractures are seldom without associated injury [3, 4, 11] and these may be difficult to diagnose using clinical tests [5]. In case of an interosseous membrane rupture a 2.5-mm proximal radial osteotomy, as with radial head resection, may allow proximal migration of the radius, distortion of the distal radioulnar joint and possible concomitant complaints [6, 8, 9]. Proximal migration of the radius with 2.5 mm most likely has the same effect as 2.5 mm overstuffing in radial head replacement and would reduce interosseous membrane tension and meanwhile increase radiocapitellar contact loads and capitellar wear [7, 10]. Furthermore, van Glabbeek et al. [10] showed that 2.5 mm of radial lengthening causes the ulna to track in varus and external rotation in UCL insufficient elbows, further predisposing the elbow to degenerative arthritis. With great interest we have read the article ‘Radial shortening osteotomy reduces radiocapitellar contact pressures while preserving valgus stability of the elbow’ of Hackl et al. [2]. In a biomechanical analysis of 14 cadaveric specimens before and after shortening osteotomy of the proximal radius by 2.5 mm they determined a significant decrease in radiocapitellar contact pressures up to 250 N of axial loading (p < 0.041), without compromising valgus stability. As such, they concluded that shortening osteotomy of the radial head may be a promising treatment option to decrease pain levels in isolated radiocapitellar osteoarthritis. Herewith, they offer an interesting additional view in difficult to treat radiocapitellar osteoarthritis. Three critical points deserve attention before performing this technique on a large scale; ulnohumeral degeneration, diagnosing isolated radiocapitellar osteoarthritis and need for follow-up. A significant decrease in radiocapitellar contact pressures up to 250N of axial loading may reduce pain during everyday activities in patients with radiocapitellar osteoarthritis. On the opposite, this also means a significant increase in ulnohumeral loading during everyday