Fernández-Carnero Josué, Fernández-de-Las-Peñas César, de la Llave-Rincón Ana Isabel, Ge Hong-You, Arendt-Nielsen Lars
Department of Physical Therapy, Occupational Therapy, Rehabilitation and Physical Medicine, Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain.
Clin J Pain. 2007 May;23(4):353-60. doi: 10.1097/AJP.0b013e31803b3785.
Referred pain and pain characteristics evoked from the extensor carpi radialis brevis, extensor carpi radialis longus, extensor digitorum communis, and brachioradialis muscles was investigated in 20 patients with lateral epicondylalgia (LE) and 20-matched controls.
Both groups were examined for the presence of myofascial trigger points (TrPs) in a blinded fashion. The quality and location of the evoked referred pain, and the pressure pain threshold (PPT) at the lateral epicondyle on the right upper extremity (symptomatic side in patients, and dominant-side on controls) were recorded. Several lateral elbow pain parameters were also evaluated.
Within the patient group, the elicited referred pain by manual exploration of 13 out of 20 (65%) extensor carpi radialis brevis muscles, 12/20 (70%) extensor carpi radialis longus muscles, 10/20 (50%) brachioradialis muscles, and 5/20 (25%) extensor digitorum communis muscles, shares similar pain patterns as their habitual lateral elbow and forearm pain. The mean number of muscles with TrPs for each patient was 2.9 [95% confidence interval (CI) 1,4] of which 2 (95% CI 1,3) were active, and 0.9 (95% CI 0,2) were latent TrPs. Control participants only had latent TrPs (mean: 0.4; 95% CI 0,2). TrP occurrence between the 2 groups was significantly different for active TrPs (P<0.001), but not for latent TrPs (P>0.05). The referred pain pattern was larger in patients than in controls, with pain referral to the lateral epicondyle (proximally) and to the dorso-lateral aspect of the forearm in the patients, and confined to the dorso-lateral aspect of the forearm in the controls. Patients with LE showed a significant (P<0.001) lower PPT (mean: 2.1 kg/cm; 95% CI 0.8, 4 kg/cm) as compared with controls (mean: 4.5 kg/cm; 95% CI 3, 7 kg/cm). Within the patient group, PPT at the lateral epicondyle was negatively correlated with both the total number of TrPs (rs=-0.63; P=0.003) and the number of active TrPs (rs=-0.5; P=0.02): the greater the number of active TrPs, the lower the PPT at the lateral epicondyle.
Our results suggest that in patients with LE, the evoked referred pain and its sensory characteristics shared similar patterns as their habitual elbow and forearm pain, consistent with active TrPs. Lower PPT and larger referred pain patterns suggest that peripheral and central sensitization exists in LE.
对20例桡侧伸腕短肌、桡侧伸腕长肌、指总伸肌和肱桡肌引发的牵涉痛及疼痛特征进行研究，以20例匹配的对照者作为对照。
对两组患者均采用盲法检查肌筋膜触发点（TrP）的存在情况。记录诱发牵涉痛的性质和部位，以及右上肢外侧髁（患者的患侧，对照者的优势侧）的压痛阈（PPT）。还评估了几个外侧肘部疼痛参数。
在患者组中，通过手法探查，20例桡侧伸腕短肌中有13例（65%）、20例桡侧伸腕长肌中有12例（70%）、20例肱桡肌中有10例（50%）、20例指总伸肌中有5例（25%）诱发的牵涉痛，其疼痛模式与其习惯性外侧肘部和前臂疼痛相似。每位患者有TrP的肌肉平均数量为2.9[95%置信区间（CI）1,4]，其中2个（95%CI 1,3）为活跃TrP，0.9个（95%CI 0,2）为潜伏TrP。对照参与者仅有潜伏TrP（平均：0.4；95%CI 0,2）。两组之间活跃TrP的TrP发生率差异有统计学意义（P<0.001），但潜伏TrP的差异无统计学意义（P>0.05）。患者的牵涉痛模式比对照者更大，患者的疼痛牵涉到外侧髁（近端）和前臂的背外侧，而对照者的疼痛局限于前臂的背外侧。与对照者（平均：4.5kg/cm；95%CI 3,7kg/cm）相比，外侧肘上髁炎患者的PPT显著降低（P<0.001）（平均：2.1kg/cm；95%CI 0.8,4kg/cm）。在患者组中，外侧髁的PPT与TrP总数（rs=-0.63；P=0.003）和活跃TrP数量（rs=-0.5；P=0.02）均呈负相关：活跃TrP数量越多，外侧髁的PPT越低。
我们的结果表明，在外侧肘上髁炎患者中诱发的牵涉痛及其感觉特征与其习惯性肘部和前臂疼痛的模式相似，与活跃TrP一致。较低的PPT和较大的牵涉痛模式表明外侧肘上髁炎存在外周和中枢敏化。
