Saper Michael G, Fantozzi Peter, Bompadre Viviana, Racicot Mimi, Schmale Gregory A
Department of Orthopedics and Sports Medicine, Seattle Children's, Seattle, Washington, USA.
Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, Washington, USA.
Orthop J Sports Med. 2019 Mar 1;7(3):2325967119828953. doi: 10.1177/2325967119828953. eCollection 2019 Mar.
Return to sport (RTS) after patellar stabilization surgery involves the return of strength and dynamic knee stability, which can be assessed using isometric strength and functional performance testing.
To investigate the results of isometric strength and functional RTS testing between the surgical and uninvolved limbs in adolescent patients who underwent medial patellofemoral ligament (MPFL) reconstruction for patellar instability.
Case series; Level of evidence, 4.
A retrospective review of adolescent patients who underwent MPFL reconstruction identified 28 patients (20 female, 8 male) who also underwent isometric and functional RTS testing. Data were compared with the uninvolved limb. The recovery of muscle strength was defined by a limb symmetry index (LSI) ≥90%. Differences in peak torque were compared using the Wilcoxon signed-rank test. Correlations were examined between dependent and independent variables using the Spearman correlation.
The mean age of the patients was 14.9 years (range, 12-16 years). Reconstruction was performed with a hamstring autograft in 17 (60.7%) patients. Concomitant tibial tubercle osteotomy was performed in 10 (35.7%) patients. Testing was performed at a mean 7.4 months (range, 5.5-11.9 months) postoperatively. The mean LSIs for quadriceps and hamstring strength were 85.3% and 95.1%, respectively. For knee extension, there was a statistically significant difference between isometric peak torque measured in the surgical and uninvolved limbs ( = .001). Only 32.0% of patients passed all 4 hop tests. Also, 63.0% of patients achieved an anterior reach asymmetry of <4 cm on the Lower Quarter Y-Balance Test (YBT-LQ). There were no statistically significant differences in isometric strength testing, hop tests, or the YBT-LQ based on graft type or concomitant procedures. There was no correlation between isometric strength and performance on the YBT-LQ or hop tests.
Adolescent athletes undergoing MPFL reconstruction may need prolonged rehabilitation programs beyond 8 months to allow the adequate recovery of muscle strength for safe RTS. There is a significant deficit in isometric quadriceps strength in the surgical limb after surgery. Further investigation is needed to determine safe RTS criteria after MPFL reconstruction in the pediatric and adolescent population.
髌骨稳定手术后恢复运动（RTS）涉及力量恢复和膝关节动态稳定性恢复，这可通过等长肌力测试和功能表现测试进行评估。
研究接受内侧髌股韧带（MPFL）重建术治疗髌骨不稳定的青少年患者手术侧与未受累侧肢体的等长肌力及功能性RTS测试结果。
病例系列研究；证据等级为4级。
对接受MPFL重建术的青少年患者进行回顾性分析，确定28例（20例女性，8例男性）同时接受了等长肌力和功能性RTS测试的患者。将数据与未受累侧肢体进行比较。肌肉力量恢复定义为肢体对称指数（LSI）≥90%。使用Wilcoxon符号秩检验比较峰值扭矩差异。使用Spearman相关性分析检验自变量与因变量之间的相关性。
患者的平均年龄为14.9岁（范围12 - 16岁）。17例（60.7%）患者采用腘绳肌自体移植物进行重建。10例（35.7%）患者同时进行了胫骨结节截骨术。术后平均7.4个月（范围5.5 - 11.9个月）进行测试。股四头肌和腘绳肌力量的平均LSI分别为85.3%和95.1%。对于膝关节伸展，手术侧与未受累侧肢体测量的等长峰值扭矩之间存在统计学显著差异（P = .001）。仅32.0%的患者通过了所有4项单腿跳测试。此外，63.0%的患者在下肢Y平衡测试（YBT - LQ）中前伸不对称度<4 cm。基于移植物类型或伴随手术，等长肌力测试、单腿跳测试或YBT - LQ均无统计学显著差异。YBT - LQ或单腿跳测试的等长肌力与表现之间无相关性。
接受MPFL重建术的青少年运动员可能需要超过8个月的长期康复计划，以实现肌肉力量的充分恢复从而安全地恢复运动。术后手术侧肢体的等长股四头肌力量存在显著不足。需要进一步研究以确定儿科和青少年人群MPFL重建术后安全的RTS标准。
