BACKGROUND Lower limb amputations performed after trauma are associated with a high risk of revision surgery. While the factors influencing revision surgery in the upper limbs have been studied, no studies have analyzed these factors in the lower limbs. Existing explanations for these revision surgeries are unclear, often leaving patients uninformed. Surgeons also lack the tools to explain the factors that influence repeat operations to patients. Therefore, the aim of this study was to provide surgeons with some answers so they can inform their patients undergoing posttraumatic lower limb amputation, whether military or civilian. QUESTIONS/PURPOSES (1) What was the survivorship of the initial amputation free from any revision surgery? (2) What patient- and injury-related factors were associated with revision amputation? (3) Do these factors influence functional outcomes in these patients? METHODS A single-center, retrospective study was conducted between January 2010 and February 2020 on patients who had undergone traumatic lower limb amputation. Between January 2010 and February 2020, 322 patients underwent amputation or were followed up at Percy Military University Hospital. Thirty-one patients had undergone amputation at another center, 178 had undergone amputation for nontraumatic reasons, and 27 patients had only upper limb amputations. Of those remaining, 1 died before 6 months, and 6% (5 of 86) were not fitted with a prosthesis, leaving 99% (85 of 86) for survivorship free from revision analysis and 93% (80 of 86) for functional endpoints analysis in this retrospective study at a median of 6.5 years (IQR 5 to 9) following the index amputation. The median age at the time of amputation was 31 years (IQR 26 to 52), 85% (72 of 85) of patients were men, and 31% (26 of 85) were military personnel. Revision surgery was defined as surgery performed at or after 6 months to ensure that the residual limb was healed and fitted with a prosthesis. Revision procedures performed before 6 months (median 2 [IQR 0 to 7]) were considered as part of the initial residual limb formation surgery. We performed Kaplan-Meier survivorship analysis for the time free from revision amputation from 6 months after amputation. We considered the competitive risk of death using a Fine-Gray model by an ascending stepwise procedure. To answer our third research question, we performed a chart review and assessed patients' use of prostheses and assistive devices and the percentage of patients who returned to work. An ordinal logistic regression was used to analyze the factors influencing functional outcome using an ascending stepwise procedure. RESULTS A total of 85 patients (94 limbs) were included, of whom 25 (27 limbs) underwent a revision surgery on the residual limb > 6 months after amputation. Kaplan-Meier survival estimates indicated that 5 years after the initial amputation 64% (95% confidence interval 53% to 77%) of the patients remained free from revision surgery on their residual limb. Factors associated with increased odds of revision amputation were smoking (subdistribution HR 2.6 [95% CI 1.2 to 5.8]; p = 0.02) and an age of > 50 years (subdistribution HR 0.3 [95% CI 0.1 to 0.8]; p = 0.01). Ninety-four percent (80 of 85) of patients were fitted with prostheses, and 40% (32 of 80) of patients used material or human assistance for simple activities of daily living. Seventy-one percent of patients (57 of 80) had returned to work. Ordinal logistic regression revealed an association between preinjury sports activity and the absence of need for assistance in daily activities (OR 9 [95% CI 2.9 to 31.8]; p < 0.001). CONCLUSION Smoking appeared to be an associated risk factor for residual limb revision surgery in posttraumatic lower limb amputations and is potentially modifiable. Being at least 50 years of age seemed to be associated with a lower incidence of revision surgery, which is probably linked to lower functional demands made on limbs beyond this age. Our study showed a remarkable rate of fitting with a prosthetic device, with an improved functional result if the patient was athletic before the trauma. These results provide more precise information on the care pathway to be considered for each patient. A study with a much larger sample would make it possible to assess the risk factors for the occurrence of each complication involving revision surgery. LEVEL OF EVIDENCE Level III, therapeutic study.

中文翻译：

---

与残肢翻修手术相关的因素和创伤后下肢截肢患者的功能结果有哪些？


背景 创伤后进行的下肢截肢与翻修手术的高风险相关。虽然已经研究了影响上肢翻修手术的因素，但没有研究分析下肢的这些因素。这些翻修手术的现有解释尚不清楚，往往使患者不知情。外科医生也缺乏向患者解释影响重复手术的因素的工具。因此，本研究的目的是为外科医生提供一些答案，以便他们可以告知接受创伤后下肢截肢的患者，无论是军人还是平民。问题/目的 （1） 初次截肢未接受任何翻修手术的存活率是多少？（2） 哪些患者和损伤相关因素与翻修截肢相关？（3） 这些因素会影响这些患者的功能结局吗？方法 2010 年 1 月至 2020 年 2 月期间对接受创伤性下肢截肢的患者进行了一项单中心回顾性研究。2010 年 1 月至 2020 年 2 月期间，322 名患者接受了截肢手术或在珀西军事大学医院接受了随访。31 名患者在另一个中心接受了截肢手术，178 名患者因非创伤原因接受了截肢手术，27 名患者仅接受了上肢截肢手术。在剩下的人中，1 人在 6 个月前死亡，6% （86 人中的 5 人） 没有安装假体，剩下 99% （86 人中的 85 人） 没有翻修分析和 93% （86 人中的 80 人） 在这项回顾性研究中位为指数截肢后 6.5 年 （IQR 5 至 9）。 截肢时的中位年龄为 31 岁 （IQR 26 至 52），85% （85 例中的 72 例） 患者为男性，31% （85 例中的 26 例） 为军人。翻修手术定义为在 6 个月或之后进行的手术，以确保残肢愈合并安装假肢。在 6 个月之前进行的翻修手术 （中位数 2 [IQR 0 至 7]）被认为是初始残肢形成手术的一部分。我们对截肢后 6 个月起翻修截肢后无时间进行了 Kaplan-Meier 幸存者分析。我们使用 Fine-Gray 模型通过升序逐步程序考虑了竞争性死亡风险。为了回答我们的第三个研究问题，我们进行了图表审查并评估了患者对假肢和辅助设备的使用情况以及重返工作岗位的患者百分比。使用顺序 logistic 回归来使用升序逐步程序分析影响功能结果的因素。结果 共纳入 85 例患者 （94 肢），其中 25 例 （27 肢） 在截肢后 6 个月行残肢 > 翻修手术。Kaplan-Meier 生存估计表明，初次截肢后 5 年（95% 置信区间 53% 至 77%）的患者仍未接受残肢翻修手术。与翻修截肢几率增加相关的因素是吸烟（亚分布 HR 2.6 [95% CI 1.2 至 5.8];p = 0.02）和年龄 > 50 岁（亚分布 HR 0.3 [95% CI 0.1 至 0.8];p = 0.01）。94% （85 名中的 80 名） 的患者安装了假肢，40% （80 名中的 32 名） 的患者使用材料或人工帮助进行简单的日常生活活动。71% 的患者 （80 名中的 57 名） 已重返工作岗位。 顺序 logistic 回归显示，受伤前的体育活动与日常活动中不需要帮助之间存在关联 （OR 9 [95% CI 2.9， 31.8];p < 0.001）。结论 吸烟似乎是创伤后下肢截肢手术残余肢修复手术的相关危险因素，并且有可能改变。至少 50 岁似乎与修复手术的发生率较低有关，这可能与超过此年龄后对肢体的功能需求较低有关。我们的研究表明，假肢装置的安装率显着，如果患者在创伤前是运动的，则功能结果会得到改善。这些结果为每位患者要考虑的护理途径提供了更准确的信息。样本量大得多的研究将有可能评估涉及翻修手术的每种并发症发生的危险因素。证据级别 III 级，治疗研究。