Department of Orthopaedics and Rehabilitation, Milton S. Hershey Medical Center, Penn State Health, Hershey, Pennsylvania, U.S.A.
Department of Orthopaedics and Rehabilitation, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, U.S.A.
Arthroscopy. 2018 Feb;34(2):513-518. doi: 10.1016/j.arthro.2017.08.267.
To determine whether (1) tunnels that breach the anterior cortex of the patella result in increased fracture risk and (2) transosseous tunnels drilled across the patella significantly reduce the tensile force needed to fracture the patella.
Twenty-six fresh-frozen cadaveric human patellas were randomized to 1 of 3 groups: a control group with unmodified patellas, a group with 2 transverse tunnels (TT) that did not breach the anterior cortex, and a group with 2 TT that breached the anterior cortex of the patella (PA). Patellas were connected in series to a load cell via freeze clamp attachments to the quadriceps and patellar tendons. Pull was fixed at 45° with the patella set in the trochlear groove of a synthetic femur. Patellas were loaded cyclically, then to failure.
Twenty-six patellas were tested (mean age = 71.4 years; range = 37-95, standard deviation [STD] = 11.5 years). PA patellas were more likely to fracture through the tunnel than TT patellas (100% vs 25%, P = .033). Control, TT, and PA groups failed at 1,915 N (STD = 508 N), 1,901 N (STD = 884 N), and 1,640 N (STD = 625 N), respectively. There was no statistically significant difference in overall load to failure between control and TT (P = .969), control and PA (P = .321), and TT and PA (P = .488) groups.
Transosseous patellar tunnels for medial patellofemoral ligament reconstruction that breached the anterior cortex were more likely to fracture during longitudinal load than those that did not breach the anterior cortex. However, we found no statistically significant difference in the tensile load to failure between native patellas and patellas with either type of transosseous tunnel.
The results of this study show that breaching the anterior cortex during transosseous drilling increases the risk of a patellar fracture occurring through the transosseous tunnel.
确定（1）穿过髌骨前皮质的隧道是否会增加骨折风险，以及（2）穿过髌骨的贯穿隧道是否会显著降低髌骨断裂所需的拉伸力。
26 个新鲜冷冻的人髌骨随机分为 3 组：未经修改的髌骨对照组、未穿过髌骨前皮质的 2 个横向隧道（TT）组和穿过髌骨前皮质的 2 个 TT 组（PA）。髌骨通过冷冻夹连接到髌骨和股四头肌肌腱上的负载单元。将拉力固定在 45°，髌骨置于合成股骨滑车槽内。髌骨进行循环加载，然后直至失效。
26 个髌骨进行了测试（平均年龄=71.4 岁；范围=37-95，标准差[STD]=11.5 岁）。PA 髌骨更有可能在隧道处断裂，而不是 TT 髌骨（100%对 25%，P=0.033）。对照组、TT 组和 PA 组分别在 1915N（STD=508N）、1901N（STD=884N）和 1640N（STD=625N）时失效。对照组和 TT 组（P=0.969）、对照组和 PA 组（P=0.321）以及 TT 组和 PA 组（P=0.488）之间的总失效负载无统计学差异。
用于内侧髌股韧带重建的穿过髌骨的隧道，如果穿过前皮质，在纵向负荷下更有可能断裂，而未穿过前皮质的隧道则不太可能断裂。然而，我们发现，在拉伸破坏负载方面，天然髌骨与任何类型的贯穿隧道的髌骨之间没有统计学上的显著差异。
本研究结果表明，在贯穿钻孔过程中穿过前皮质会增加通过贯穿隧道发生髌骨骨折的风险。
