Background: 

Pain and function, as reflected by patient-reported outcome measures (PROMs), can influence improvement after total knee arthroplasty (TKA) and can reflect the extent of patient access to orthopaedic surgical care. We aimed to (1) categorize patients according to pain and function PROM phenotypes, (2) identify patient characteristics associated with poor preoperative pain and function, and (3) assess relationships between baseline characteristics and PROM phenotypes.

Methods: 

A prospective cohort of 14,079 TKAs was enrolled. Demographics, comorbidities, surgical details, and preoperative PROMs were collected. Outcomes included preoperative Knee injury and Osteoarthritis Outcome Score (KOOS) Pain (P) and Physical Function (PS) subscores, stratified by demographics. Patients were then categorized into 4 PROM phenotypes defined on the basis of the cohort medians: above or equal to the median for both pain and function scores (P+PS+), below the median for both pain and function (P−PS−), above or equal to the median for pain but below the median for function (P+PS−), and below the median for pain but above or equal to the median for function (P−PS+). Descriptive statistics and multivariable regression analyses were calculated.

Results: 

The largest PROM phenotype was P−PS− (39.4%), followed by P+PS+ (38.9%). The cohort with discordantly poor function but high pain scores (less pain) was the smallest cohort (9.9%). Preoperative KOOS-Pain and KOOS-PS scores at or below the 25th percentile were independently associated with younger age, female sex, higher body mass index (BMI), non-White race, current smoking, lower education, non-commercial insurance, and higher Charlson Comorbidity Index (CCI). Multivariate logistic regression showed that patients in the P+PS+ category were older (odds ratio [OR] = 1.56), were more likely to be male (OR = 2.00), had a lower BMI (OR = 0.67), had more education (OR = 1.63), had a lower CCI, and were less likely to be Black (OR = 0.80) or Other (OR = 0.62) race, be a current smoker (OR = 0.62), and have commercial insurance (OR = 0.74), compared with the P−PS− phenotype.

Conclusions: 

Younger age, obesity, non-White race, female sex, current or recent smoking, non-commercial insurance, and higher CCI were associated with worse pre-TKA PROMs and poor pain-function phenotype combinations. Such a pattern may indicate barriers to TKA access among these patient populations leading to advanced levels of impairment at the time of treatment.

Level of Evidence: 

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

中文翻译：

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人口统计学和社会经济决定因素与初次 TKA 术前患者报告的疼痛和功能不佳相关：一项针对 14,079 名患者的队列研究

背景： 

疼痛和功能，如患者报告的结果测量 (PROM) 所反映的那样，可以影响全膝关节置换术 (TKA) 后的改善，并且可以反映患者获得骨科手术护理的程度。我们的目的是 (1) 根据疼痛和功能 PROM 表型对患者进行分类，(2) 确定与术前疼痛和功能不佳相关的患者特征，以及 (3) 评估基线特征和 PROM 表型之间的关系。

方法： 

招募了 14,079 例 TKA 的前瞻性队列。收集了人口统计学、合并症、手术细节和术前 PROM。结果包括术前膝关节损伤和骨关节炎结果评分 (KOOS) 疼痛 (P) 和身体功能 (PS) 子评分，按人口统计学分层。然后根据队列中位数将患者分为 4 种 PROM 表型：疼痛和功能评分均高于或等于中位数 (P+PS+)，疼痛和功能均低于中位数 (P−PS−)，高于或等于疼痛中位数但低于功能中位数 (P+PS-)，以及低于疼痛中位数但高于或等于功能中位数 (P-PS+)。计算了描述性统计和多变量回归分析。

结果： 

最大的 PROM 表型是 P−PS− (39.4%)，其次是 P+PS+ (38.9%)。功能异常差但疼痛评分高（疼痛较轻）的队列是最小的队列 (9.9%)。术前 KOOS-Pain 和 KOOS-PS 评分等于或低于第 25 个百分位数与年龄较小、女性、较高的体重指数 (BMI)、非白人种族、当前吸烟、较低的教育程度、非商业保险和以及查尔森合并症指数 (CCI) 更高。多变量逻辑回归显示 P+PS+ 类别的患者年龄较大（比值比 [OR] = 1.56），更有可能是男性（OR = 2.00），BMI 较低（OR = 0.67），受教育程度较高（ OR = 1.63)，CCI 较低，并且不太可能是黑人 (OR = 0.80) 或其他 (OR = 0.62) 种族，目前吸烟者 (OR = 0.62)，并且有商业保险 (OR = 0.74) ,

结论： 

较年轻、肥胖、非白人种族、女性、当前或最近吸烟、非商业保险和较高的 CCI 与较差的 TKA 前 PROM 和较差的疼痛功能表型组合相关。这种模式可能表明这些患者群体在接受 TKA 方面存在障碍，导致治疗时出现严重损伤。

证据等级： 

预后三级。有关证据等级的完整描述，请参阅作者须知。