Background 

Traumatic brachial plexus injuries (BPIs) in the nerve roots of C5 to T1 lead to the devastating loss of motor and sensory function in the upper extremity. Free functional gracilis muscle transfer (FFMT) is used to reconstruct elbow and shoulder function in adults with traumatic complete BPIs. The question is whether the gains in ROM and functionality for the patient outweigh the risks of such a large intervention to justify this surgery in these patients.

Questions/purposes 

(1) After FFMT for adult traumatic complete BPI, what is the functional recovery in terms of elbow flexion, shoulder abduction, and wrist extension (ROM and muscle grade)? (2) Does the choice of distal insertion affect the functional recovery of the elbow, shoulder, and wrist? (3) Does the choice of nerve source affect elbow flexion and shoulder abduction recovery? (4) What factors are associated with less residual disability? (5) What proportion of flaps have necrosis and do not reinnervate?

Methods 

We performed a retrospective observational study at Dr. Soetomo General Hospital in Surabaya, Indonesia. A total of 180 patients with traumatic BPIs were treated with FFMT between 2010 and 2020, performed by a senior orthopaedic hand surgeon with 14 years of experience in FFMT. We included patients with traumatic complete C5 to T1 BPIs who underwent a gracilis FFMT procedure. Indications were total avulsion injuries and delayed presentation (>6 months after trauma) or after failed primary nerve transfers (>12 months). Patients with less than 12 months of follow-up were excluded, leaving 130 patients eligible for this study. The median postoperative follow-up period was 47 months (interquartile range [IQR] 33 to 66 months). Most were men (86%; 112 of 130) who had motorcycle collisions (96%; 125 patients) and a median age of 23 years (IQR 19 to 34 years). Orthopaedic surgeons and residents measured joint function at the elbow (flexion), shoulder (abduction), and wrist (extension) in terms of British Medical Research Council (MRC) muscle strength scores and active ROM. A univariate analysis of variance test was used to evaluate these outcomes in terms of differences in distal attachment to the extensor carpi radialis brevis (ECRB), extensor digitorum communis and extensor pollicis longus (EDC/EPL), the flexor digitorum profundus and flexor pollicis longus (FDP/FPL), and the choice of a phrenic, accessory, or intercostal nerve source. We measured postoperative function with the DASH score and pain at rest with the VAS score. A multivariate linear regression analysis was performed to investigate what patient and injury factors were associated with less disability. Complications such as flap necrosis, innervation problems, infections, and reoperations were evaluated.

Results 

The median elbow flexion muscle strength was 3 (IQR 3 to 4) and active ROM was 88° ± 46°. The median shoulder abduction grade was 3 (IQR 2 to 4) and active ROM was 62° ± 42°. However, the choice of distal insertion was not associated with differences in the median wrist extension strength (ECRB: 2 [IQR 0 to 3], EDC/EPL: 2 [IQR 0 to 3], FDP/FPL: 1 [IQR 0 to 2]; p = 0.44) or in ROM (ECRB: 21° ± 19°, EDC/EPL: 21° ± 14°, FDP/FPL: 13° ± 15°; p = 0.69). Furthermore, the choice of nerve source did not affect the mean ROM for elbow flexion (phrenic nerve: 87° ± 46°; accessory nerve: 106° ± 49°; intercostal nerves: 103° ± 50°; p = 0.55). No associations were found with less disability (lower DASH scores): young age (coefficient = 0.28; 95% CI -0.22 to 0.79; p = 0.27), being a woman (coefficient = -9.4; 95% CI -24 to 5.3; p = 0.20), and more postoperative months (coefficient = 0.02; 95% CI -0.01 to 0.05]; p = 0.13). The mean postoperative VAS score for pain at rest was 3 ± 2. Flap necrosis occurred in 5% (seven of 130) of all patients, and failed innervation of the gracilis muscle occurred in 4% (five patients).

Conclusion 

FFMT achieves ROM with fair-to-good muscle power of elbow flexion, shoulder abduction, and overall function for the patient, but does not achieve good wrist function. Meticulous microsurgical skills and extensive rehabilitation training are needed to maximize the result of FFMT. Further technical developments in distal attachment and additional nerve procedures will pave the way for reconstructing a functional limb in patients with a flail upper extremity.

Level of Evidence 

Level III, therapeutic study.

中文翻译：

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成人外伤性完全性臂丛神经损伤的自由功能性股薄肌转移后的肘部屈曲强度是多少？

背景 

C5 至 T1 神经根的外伤性臂丛神经损伤 (BPI) 会导致上肢运动和感觉功能的毁灭性丧失。自由功能性股薄肌转移 (FFMT) 用于重建患有创伤性完全 BPI 的成年人的肘部和肩部功能。问题是患者在 ROM 和功能方面的收益是否超过了为这些患者进行这种手术的如此大的干预所带来的风险。

问题/目的 

(1) 成人外伤性完全性 BPI FFMT 后，肘关节屈曲、肩外展和腕关节伸展（ROM 和肌肉等级）的功能恢复情况如何？(2) 远端插入方式的选择是否影响肘、肩、腕的功能恢复？(3) 神经源的选择是否影响屈肘肩外展恢复？(4) 哪些因素与较少的残余残疾有关？(5) 有多少比例的皮瓣坏死并且没有再神经支配？

方法 

我们在印度尼西亚泗水的 Soetomo 综合医院进行了一项回顾性观察研究。2010 年至 2020 年间，共有 180 名创伤性 BPI 患者接受了 FFMT 治疗，由具有 14 年 FFMT 经验的资深骨科手外科医生实施。我们纳入了患有外伤性完全 C5 至 T1 BPI 并接受股薄肌 FFMT 手术的患者。适应症为完全撕脱伤和延迟就诊（外伤后 > 6 个月）或原发性神经转移失败后（> 12 个月）。随访时间少于 12 个月的患者被排除在外，剩下 130 名患者符合这项研究的条件。中位术后随访期为 47 个月（四分位数间距 [IQR] 33 至 66 个月）。大多数是男性（86%；130 人中有 112 人）发生过摩托车碰撞事故（96%；130 人中有 112 人）。125 名患者），中位年龄为 23 岁（IQR 19 至 34 岁）。骨科医生和住院医师根据英国医学研究委员会 (MRC) 肌肉力量评分和活动 ROM 测量肘部（屈曲）、肩部（外展）和腕部（伸展）的关节功能。方差检验的单变量分析用于根据远端附着桡侧腕短伸肌 (ECRB)、趾共伸肌和拇长伸肌 (EDC/EPL)、趾深屈肌和拇长屈肌的差异来评估这些结果(FDP/FPL)，以及膈神经、副神经或肋间神经源的选择。我们用 DASH 评分测量术后功能，用 VAS 评分测量静息时的疼痛。进行多变量线性回归分析以调查哪些患者和伤害因素与较少的残疾相关。评估了皮瓣坏死、神经支配问题、感染和再次手术等并发症。

结果 

中位肘部屈曲肌力为 3（IQR 3 至 4），活动 ROM 为 88° ± 46°。中位肩外展等级为 3（IQR 2 至 4），活动 ROM 为 62° ± 42°。然而，远端插入的选择与中位腕伸展强度的差异无关（ECRB：2 [IQR 0 至 3]，EDC/EPL：2 [IQR 0 至 3]，FDP/FPL：1 [IQR 0 至 3] 2]；p = 0.44) 或在 ROM 中（ECRB：21° ± 19°，EDC/EPL：21° ± 14°，FDP/FPL：13° ± 15°；p = 0.69）。此外，神经源的选择不影响屈肘的平均 ROM（膈神经：87°±46°；副神经：106°±49°；肋间神经：103°±50°；p = 0.55）。没有发现与较少残疾（较低的 DASH 分数）相关：年轻（系数 = 0.28；95% CI -0.22 至 0.79；p = 0.27），女性（系数 = -9.4；95% CI -24 至 5.3； p = 0.20), 和更多的术后月份（系数 = 0.02；95% CI -0.01 至 0.05]；p = 0.13）。静息疼痛的术后平均 VAS 评分为 3 ± 2。所有患者中有 5%（130 名中有 7 名）发生皮瓣坏死，4%（5 名患者）出现股薄肌神经支配失败。

结论 

FFMT 为患者实现了肘部屈曲、肩部外展和整体功能的良好肌肉力量的 ROM，但未实现良好的腕部功能。需要细致的显微外科技能和广泛的康复训练才能最大限度地提高 FFMT 的效果。远端连接和额外神经手术的进一步技术发展将为上肢连枷患者重建功能性肢体铺平道路。

证据等级 

III 级，治疗研究。