Gwilym S E, Oag H C L, Tracey I, Carr A J
Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Nuffield Orthopaedic Centre, Windmill Road, Headington, Oxford OX3 7LD, UK.
J Bone Joint Surg Br. 2011 Apr;93(4):498-502. doi: 10.1302/0301-620X.93B4.25054.
Impingement syndrome in the shoulder has generally been considered to be a clinical condition of mechanical origin. However, anomalies exist between the pathology in the subacromial space and the degree of pain experienced. These may be explained by variations in the processing of nociceptive inputs between different patients. We investigated the evidence for augmented pain transmission (central sensitisation) in patients with impingement, and the relationship between pre-operative central sensitisation and the outcomes following arthroscopic subacromial decompression. We recruited 17 patients with unilateral impingement of the shoulder and 17 age- and gender-matched controls, all of whom underwent quantitative sensory testing to detect thresholds for mechanical stimuli, distinctions between sharp and blunt punctate stimuli, and heat pain. Additionally Oxford shoulder scores to assess pain and function, and PainDETECT questionnaires to identify 'neuropathic' and referred symptoms were completed. Patients completed these questionnaires pre-operatively and three months post-operatively. A significant proportion of patients awaiting subacromial decompression had referred pain radiating down the arm and had significant hyperalgesia to punctate stimulus of the skin compared with controls (unpaired t-test, p < 0.0001). These are felt to represent peripheral manifestations of augmented central pain processing (central sensitisation). The presence of either hyperalgesia or referred pain pre-operatively resulted in a significantly worse outcome from decompression three months after surgery (unpaired t-test, p = 0.04 and p = 0.005, respectively). These observations confirm the presence of central sensitisation in a proportion of patients with shoulder pain associated with impingement. Also, if patients had relatively high levels of central sensitisation pre-operatively, as indicated by higher levels of punctate hyperalgesia and/or referred pain, the outcome three months after subacromial decompression was significantly worse.
肩部撞击综合征通常被认为是一种机械性起源的临床病症。然而，肩峰下间隙的病理学表现与所经历的疼痛程度之间存在异常情况。这些异常可能是由于不同患者对伤害性输入的处理方式存在差异所致。我们研究了撞击综合征患者中疼痛传递增强（中枢敏化）的证据，以及术前中枢敏化与关节镜下肩峰下减压术后结果之间的关系。我们招募了17名单侧肩部撞击患者和17名年龄及性别匹配的对照者，所有受试者均接受了定量感觉测试，以检测机械刺激阈值、锐性和钝性点状刺激的辨别能力以及热痛阈值。此外，还完成了用于评估疼痛和功能的牛津肩部评分，以及用于识别“神经性”和牵涉性症状的疼痛检测问卷。患者在术前和术后三个月完成这些问卷。与对照组相比，等待肩峰下减压的患者中有很大一部分存在沿手臂放射的牵涉痛，并且对皮肤点状刺激有明显的痛觉过敏（未配对t检验，p < 0.0001）。这些被认为代表了中枢性疼痛处理增强（中枢敏化）的外周表现。术前存在痛觉过敏或牵涉痛会导致术后三个月减压治疗的结果明显更差（未配对t检验，p分别为0.04和0.005）。这些观察结果证实了一部分与撞击相关的肩部疼痛患者存在中枢敏化。此外，如果患者术前中枢敏化水平相对较高，如点状痛觉过敏和/或牵涉痛水平较高所示，那么肩峰下减压术后三个月的结果会明显更差。
