Department of Orthopedic Surgery, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
Department of Orthopedic Surgery, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
J Shoulder Elbow Surg. 2020 Jun;29(6):1136-1144. doi: 10.1016/j.jse.2019.10.014. Epub 2020 Feb 5.
The preoperative status of the teres minor (Tm) can affect the outcome of reverse total shoulder arthroplasty (RTSA). The effect of preoperative Tm hypertrophy on the outcome of RTSA is unclear.
A total of 86 shoulders that underwent RTSA were retrospectively enrolled. Of these, 48 cases with a Tm occupation ratio (OR) of >0.288 in the preoperative magnetic resonance image were assigned to the hypertrophic group, and 38 cases to the control group. The two groups were compared with respect to preoperative rotator cuff tear involvement, fatty infiltration, pre- and postoperative rotator cuff ORs, pain scores, functional scores, range of motion, and muscle strength. Postoperative Tm ORs in 1-year follow-up multidetector computed tomography were compared with preoperative Tm ORs.
Preoperatively, integrities of infraspinatus (ISP) and supraspinatus were significantly different between the 2 groups (P = .001, 0.009, each). Preoperative ISP ORs were significantly related to preoperative Tm ORs (r = -0.534, P < .001). The mean pre- to postoperative change of Tm ORs in the hypertrophic group decreased (-0.029 ± 0.068), whereas that of the control group increased (+0.047 ± 0.092). Postoperative pain scores, functional scores, range of motion, and muscle strength were not different between groups.
In cases of advanced rotator cuff tear requiring RTSA, Tm hypertrophy is found to be related to tear and atrophy of the ISP, suggesting that Tm hypertrophy is a compensatory change for ISP dysfunction. However, Tm hypertrophy was observed to diminish after RTSA. Preoperative Tm hypertrophy appears to have no beneficial effect on the outcomes of RTSA.
冈下肌（Tm）的术前状态可能会影响反式全肩关节置换术（RTSA）的结果。术前 Tm 肥大对 RTSA 结果的影响尚不清楚。
回顾性纳入 86 例接受 RTSA 的患者。其中，术前磁共振成像中 Tm 占有率（OR）>0.288 的 48 例患者归入肥大组，38 例归入对照组。比较两组术前肩袖撕裂受累情况、脂肪浸润程度、术前和术后肩袖 OR、疼痛评分、功能评分、活动范围和肌肉力量。比较术后 1 年随访多层螺旋 CT 上的术后 Tm OR 与术前 Tm OR。
术前，两组间冈下肌（ISP）和冈上肌的完整性有显著差异（P =.001，0.009，各）。术前 ISP OR 与术前 Tm OR 显著相关（r = -0.534，P <.001）。肥大组 Tm OR 从术前到术后的平均变化值减小（-0.029 ± 0.068），而对照组增加（+0.047 ± 0.092）。两组间术后疼痛评分、功能评分、活动范围和肌肉力量无差异。
在需要 RTSA 的严重肩袖撕裂病例中，发现 Tm 肥大与 ISP 的撕裂和萎缩有关，提示 Tm 肥大是 ISP 功能障碍的代偿性变化。然而，RTSA 后 Tm 肥大被观察到减少。术前 Tm 肥大似乎对 RTSA 的结果没有有益的影响。
