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INTRODUCTION Our prototype wireless full-HD Augmented Reality Head-Mounted Display (AR-HMD) aims to eliminate surgeon head turning and reduce theater clutter. Learning and performance versus TV Monitors (TVM) is evaluated in simulated knee arthroscopy. METHODS 19 surgeons and 19 novices were randomized into either the control group (A) or intervention group (B) and tasked to perform 5 simulated loose-body retrieval procedures on a bench-top knee arthroscopy simulator. A cross-over study design was adopted whereby subjects alternated between devices during trials 1-3, deemed the "Unfamiliar" phase, and then used the same device consecutively in trials 4-5, to assess performance in a more "Familiarized" state. Measured outcomes were time-to-completion and incidence of bead drops. RESULTS In the unfamiliar phase, HMD had 67% longer mean time-to-completion than TVM (194.7 ± 152.6s vs 116.7 ± 78.7s, P < .001). Once familiarized, HMD remained inferior to TVM, with 48% longer completion times (133.8 ± 123.3s vs 90.6 ± 55s, P = .052). Cox regression revealed device type (OR = 0.526, CI 0.391-0.709, P < .001) and number of procedure repetitions (OR = 1.186, CI 1.072-1.311, P = .001) are significantly and independently related to faster time-to-completion. However, experience is not a significant factor (OR = 1.301, CI 0.971-1.741, P = .078). Bead drops were similar between the groups in both unfamiliar (HMD: 27 vs TVM: 22, P = .65) and familiarized phases (HMD: 11 vs TVM: 17, P = .97). CONCLUSION Arthroscopic procedures continue to be better performed under conventional TVM. However, similar quality levels can be reached by HMD when given more time. Given the theoretical advantages, further research into improving HMD designs is advocated.