Salomon Kevin, Roura Raúl, Ayala Giovanni, Wilder Lauren, Kolakowski Logan, Simon Peter, Frankle Mark A
Foundation for Orthopaedic Research and Education (FORE), Tampa, FL, USA.
University of South Florida, Morsani College of Medicine, Tampa, FL, USA.
JSES Int. 2024 Nov 14;9(2):458-465. doi: 10.1016/j.jseint.2024.10.005. eCollection 2025 Mar.
The introduction of different humeral implants for the treatment of osteoarthritis was intended to improve the ability to anatomically reconstruct the proximal humerus. New technology should ideally lead to improvements in optimal reconstruction. The primary aim of this study was to compare three humeral implant types (long stem, short stem, and stemless) to replicate the proximal humeral anatomy and assess the impact of transitions across each stem type, including initial learning curves.
This was a retrospective review of 298 patients (175 males and 123 females) who underwent anatomic total shoulder arthroplasty utilizing three following stem types: 145 long stem, 102 short stem, and 51 stemless implants. An AP radiograph which met a criterion of optimal/orthogonal view of the humeral head and stem was selected for every included patient. A best fit circle, an articular surface circle and postoperative measure of neck-shaft angle (NSA) was measured by two independent observers. The distance between the centers of two circles (center of rotation [COR] shift) and NSA were then compared for each stem type. In order to assess transitions in technology, two sets of patients in the stemmed groups were selected: initial year (79 long stem, 62 short stem) and final year (66 long, 40 short) of utilization. A cumulative sum control chart analysis was used to assess the learning curves of each of the stem types by the initial year of utilization according to the radiographic measurement of COR shift.
The stemless implant showed best reconstruction with a mean COR shift of 3.0 ± 1.6 mm and NSA of 137 ± 6° ( < .001). The transition from long stem to short stem utilization showed significantly worse COR shift and NSA, 3.3 ± 2.1 mm to 4.1 ± 1.9 mm and 138.5 ± 4.4° to 141.0 ± 4.4° (max = .032), respectively. The impact of transitions to newer technology demonstrated an increased operative time (100 to 128 and 135 min). The cumulative sum control char learning curves demonstrated a completion of the learning phases at 12 cases for both the long and short stem designs, but there was no identifiable learning phase for the stemless implant, suggesting an immediate entry to the consolidation phase.
When assessing reconstruction of the premorbid shoulder joint, the stemless implant had the greatest efficacy and shortest learning curve. Stemless anatomic humeral reconstruction is more replicable in recreating the anatomic shape of the humerus and is quicker to master compared to standard or short stemmed implants but did have a greater initial operative time.
引入不同的肱骨植入物用于治疗骨关节炎旨在提高对肱骨近端进行解剖重建的能力。理想情况下，新技术应能带来最佳重建效果的改善。本研究的主要目的是比较三种肱骨植入物类型（长柄、短柄和无柄），以复制肱骨近端解剖结构，并评估每种柄型转换的影响，包括初始学习曲线。
这是一项对298例患者（175例男性和123例女性）的回顾性研究，这些患者接受了使用以下三种柄型的解剖型全肩关节置换术：145例长柄植入物、102例短柄植入物和51例无柄植入物。为每位纳入患者选择一张符合肱骨头和柄的最佳/正交视图标准的前后位X线片。由两名独立观察者测量最佳拟合圆、关节面圆和术后颈干角（NSA）。然后比较每种柄型的两个圆中心之间的距离（旋转中心[COR]移位）和NSA。为了评估技术转换情况，在有柄组中选择两组患者：使用的第一年（79例长柄、62例短柄）和最后一年（66例长柄、40例短柄）。根据COR移位的X线测量结果，采用累积和控制图分析来评估每种柄型在使用第一年的学习曲线。
无柄植入物显示出最佳重建效果，平均COR移位为3.0±1.6mm，NSA为137±6°（P<0.001）。从长柄到短柄的转换显示COR移位和NSA明显变差，分别从3.3±2.1mm变为4.1±1.9mm，从138.5±4.4°变为141.0±4.4°（最大P=0.032）。向新技术转换的影响表现为手术时间增加（100至128分钟和135分钟）。累积和控制图学习曲线表明，长柄和短柄设计在12例手术时完成学习阶段，但无柄植入物没有可识别的学习阶段，这表明其立即进入巩固阶段。
在评估病前肩关节的重建时，无柄植入物疗效最佳且学习曲线最短。与标准或短柄植入物相比，无柄解剖型肱骨重建在重现肱骨解剖形状方面更具可重复性，且掌握起来更快，但初始手术时间更长。
