骨关节炎性疼痛

骨关节炎为由于老年化过程而出现的磨损性关节变性。疼痛是病人就医时最多的主诉。骨性关节炎早期蹲下去站起来或跑楼梯时两膝酸软无力慢慢的才演变成疼痛、肿胀、畸形及功能障碍.膝关节骨性关节炎的疼痛和其他疼痛比有明显的区别,由于长时间行走,下蹲后酸困不适,逐步发展为行走时疼痛,物可止疼,部分影响日常生活。原发性骨关节炎犯其他正常侵犯其他正常的骨关节软骨面。继发性骨关节炎是创伤、关节病（如Legg-Perthe病）或轻微畸形（如轻度髋臼发育不良导致长期关节不交合）的后遗症。同济大学附属东方医院疼痛科王祥瑞

　骨关节炎是所有骨关节病中最常见，整个人群中约有30~50%受累。遗传性未得到证实。女性较男性患者多。事实上超过55岁的人都有一点患此病的X线证据，幸而只有不到一半有X线证变化的病人感到有关节症状，通常是在60岁开始出现。虽然特异性刺激因素尚不清楚，但是在骨关节炎关节中最早的组织病理学变化是在关节软骨的最外层中丧失粘液多糖基质。结果是软骨的机械性能发生改变，对变形的耐受力下降。变弱的表层软骨因对正常负荷增加变形而发生裂隙。这导致应力分布不均匀地传导至深层软骨及其下面的软骨下骨。集中的应有尽有力进一步加速外民支软骨磨损及变薄，也加速深层碎裂和裂隙的扩布。在关节内软骨碎片导致低度慢性囊炎和关节积液。

　如果受损的关节持续负重或承受应力，软骨变薄可进行下去，直到最后全层软骨消失。软骨破坏过程中，软骱下骨胳的负荷逐渐加重，骨负荷加重刺激骨胳重新塑和新骨沉积，表现为边缘的骨赘形成和软骨下骨质硬化。过度负荷的软骨下骨质中的细微骨折激起慢性炎症反应，坏死的骨骼被纤维组织替代导致软骨下囊肿形成。

一. 膝关节骨性关节炎疼痛特点

1.活动疼:膝关节长期处于某一静位置后刚开始变换体位时引起的疼痛,在活动后减轻,负重和活动多时又加重.

2负重痛:骑自行车,游泳时膝部不痛,而上下楼、上下坡、坐蹲站起时疼痛,提担重物时疼痛加重,主要是加重了膝关节的负荷而引起.突然站起时就会有剧痛,而活动一下再站起来时症状往往就会消失.

3主动活动痛而被动活动轻,主动活动时肌肉收缩加重关节负荷.

 4)休息痛:膝关节长期处于某一静止不动或夜间睡觉时疼痛,这主要是因为静脉回流不畅,髓腔及关节内压力增高有关变换体位时就会缓解.

5"老寒腿":秋冬加重,天气变换时加重,故许多人又称它为"老寒腿""气象台".

 6肿胀是膝关节骨性关节炎的重要表现:①由于病变后期关节关节滑膜和关节囊受脱落的软骨碎片刺激而充血、水肿、增生、肥厚、滑液增多、产生滑膜炎,导致关节积液引起.②增生的滑膜肥厚,脂肪垫增大、骨质增生、骨赘形成引起.

7畸形:以膝内翻为主,这与股骨内踝圆而凸,而胫骨平台凹陷、骨质相对疏松,内侧半月板薄弱,有的伴有小腿内旋.畸形使负荷更不均匀,畸形越发严重.另外由于髌骨力线不正,或髌骨增大.股内侧肌萎缩,髌骨内外侧牵拉力量不均匀,外侧强大的支撑带牵拉髌骨使髌骨外移,髌骨增生.

8弹响:①关节处肌腱或腱周组织炎性渗出,产生摩擦音.②来自关节内:大块软骨缺损,半月板破裂及游离体夹在关节间隙活动时来回滑动引起.

9交锁:是由于大块游离体或半月板(破裂)夹在两关节中间,是关节突出剧痛,易摔倒,关节不能伸屈,负重.假性,滑膜皱襞长进两骨之间.频繁的克正交锁,无疑是损伤关节软骨面.

10不稳:体位支撑稳定力量减弱如股四头肌萎缩,侧向不稳,步态摇摆(关节反复肿胀、积液较多、关节松弛.

11关节屈伸活动范围减少:关节经常肿胀,被迫于轻度屈曲位时时增加腔内容积.久而久之容易出现周围肌痉挛,活动受限.而伴膝肌力下降,关节囊萎缩,骨赘增生、髌骨活动度减少,增生物粘连引起.关节不可能伸直.

二.临床表现

　1.症状与体征：骨关节炎是一局部病变无全身症状。无症状的退行性关节变化常见于手和脊柱，而在负重的膝及髋关节等常是僵凝和疼痛的。特别是在一在活动之后更是如此。症状可以是发作性的。可长期自行缓解或缓慢地稳步发展，导至严重的残废和难治的疼痛，不适的特征是夜间较重，而早上僵硬程度最轻。单关节骨关炎不多见。典型的为侵犯双侧膝关节，不过一侧较另一侧严重。髋关节骨关节炎发生得轻些少些，但仍不少见。半数以上患者的手指远端关节出现结节性肿胀（Heberden's 结节），拇指腕骨关节及大  趾的，跖趾关节疼痛性变性最常见。踝，肩及肘关节很少受到侵犯，在所有关节中腕关节受累最少。

　引入注意的是检查骨关节炎性关节时无炎症性体征。如有渗出液，一般都很轻微。通常无发红和发热现象。最突出的表现是活动时疼痛，被动活动可触到磨擦感。活动范围试验显示受累膝关节不能完全屈曲和伸直，髋关节内旋受限。病情越发展，活动范围更严重受限。随着关节内侧和外侧明显受累，可出现膝内翻或外翻畸形。手远侧指间关节的Heberden's结节是典型的表现。这些前侧骨突起表明有边缘性骨赘。近侧指间关节可出现类似的退行性变。这种病变称为 Bouchard氏结节。

2.实验室检查：实验室检查通常正常。

3.X 线表现：X线所见与组织病理的变性期一致，早期变化有轻度关节间隙窄狭窄，受累关节周围有很轻的骨赘形成（骨刺）。更严重的疾病，表现为关节间隙更窄狭，在关节边缘有明显骨赘形成，软骨下骨坚实硬化以及软骨下囊肿。不完全脱位和关节间隙狭窄只是在关节承受重力时所拍的片中常是明显的但两侧的膝及髋关节都应拍片。

三.治疗

1.外支撑法：骨关节炎的处理方法取决于疾病处于何阶段，当一负重的关节变性较轻时，使用外支撑物如手杖，拐杖或步行器可使症状明显缓解。虽然骨关节炎的软骨实际愈合很难证实，但通过支架减轻压力，关节疼痛的缓解有时是很明显的。

2.药物治疗：抗炎药物对骨关节炎的作用比起类风湿性关节炎或痛风要小些。试用非类固醇类抗炎药物是有根据的，正如某些病人所言，在使用后有一定缓解。止痛药，热敷法，超声及按摩亦可使症状缓解。增强关节的运动等物理疗法，偶尔有用，减轻负重是有利的。

3.手术治疗：关节成形术使严重和可致残的骨关炎的处理明显改善，多数髋或膝关节病的患者确实消除了疼痛，一般也改善了关节活动。胶合剂所作的假体部位，用十多年后会松动，而全关节成形术对老年和活动较少的人，却有维持最长时间的效果。

　　截骨术对40~60岁的人有益，特别对较轻的关节病。经手术重新调整关节位置，使关节的负重转移至损伤较少的软骨，可在术后数年内维持关节功能。如果需要，以后还可以作关节置换，而组成部件失败的可能性将成比例地降低。

Osteoarthritis has traditionally been described as “wear and tear” joint degeneration attributable to the aging process. Pain due to osteoarthritis constitutes the most common joint complanint for which patien is seek medical attention. Primary osteoarthritis affects the articular cartilage of otherwise normal joints. Secondary osteoarthritis occurs as a sequela of trauma， joint disease such as Legg-Perthes disease， or subtle anomalies such as mild acetabular dysplasia resulting in long-standing joint incongruity.

Osteoarthritis is the most common of all arthropathies， affecting roughly 30-50% of the entire population. Heritability has not been demonstrated. Women are more often affected than men， though virtually all persons overage 55 have some x-ray evidence of this disease. Fortunately， less than half of patients with x-ray changes will experience joint symptoms. Onset of symptomatic disease is usually in the sixth decade.

Though the specific in citing agent remains unclear， the earliest histopathologic change in osteoarthritic joints is loss of mucopolysaccharide ground substance in the outermost layers of articular cartilage. As a result the mechanical properties of the cartilage are altered and resistance to deformation is lowered. The weakened superficial layers of cartilage develop fissures in response to increased deformation by normal loads. This results in uneven distribution of stress transmission to deeper layers of cartilage and to the underlying subchondral bone. This concentration of stress further accelerates cartilage wear with thinning of outer layers and propagation of cracks and fissures in the deeper layers. Cartilage debris within the joint results in low-grade chronic inflammatory synovitis and joint effusion.

　If weight bearing or stress loading of the affected joint continues， thinning of the cartilage may progress to eventual full-thickness cartilage loss. The subchondral bone bears progressively greater loads as cartilage destruction evolves. Increased loading of bone stimulates bone remodeling and new bone deposition， manifested by marginal osteophyte formation and sclerosis within the overloaded subchondral bone incite a chronic inflammatory response Replacement of nercrotic bone by fibrous tissue results in subchondral cyst formation.

　Clinical Findings

　　a. Sympoms and Signs： Osteoarthritis is a local condition without systemic manifestations. Asymptomatic degenerative joint changes in the hands and spine are common， but weight-bearing joints such as the knee and hip are often stiff and painful， particularly following the activities of the day. Symptoms may be episodic， with long periods of spontaneous remission， or slowly but steadily progressive， resulting in profound disability and intractable pain. Discomfort is characteristically more severe at night， and morning stiffness is minimal. Monarticular osteoarthritis is unusual. Both knees are typically involved， though one usually more extensively than the other. Osteoarthritis of the hip occurs slightly less frequently but is still quite common， Nodular swelling of the distal joints of the fingers （Heberden's nodes） is painful in over half of affected individuals. and painful degeneration of the carpometacarpal joint of the thumb and the metocar pophalangeal joint of the great toe is common， the ankle， shoulder， and elbow are rarely involved， and the wrist least frequently of all.

Examination of osteoarthritic joints is remarkable for the absence of inflammatory signs. Effusion， when present， is slight， and redness and warmth are usually absent. Pain with motion is the predominant finding， and crepitation may be palpated with passive motion. Rnage-of-motion testing reveals limitation of terminal flexion and extension in the involved knee joints and internal rotation in involved hips. More severe limitation is characteristic of more advanced disease. Varus or valgus deformity of the knee may be present， depending upon the predominance of involvement of the medial or lateral joint compartment. Heberden's nodes of the distal interphalangeal joints of the hand are classic findings. These dorsal bony prominences represent marginal osteophytes， Similar degenerative changes of the proximal interphalangeal joints may be present and are knoiwn as Bouchard’s nodes.

　b. Laboratory Findings： Laboratory studies are usually normal.

　c. X-Ray Findings： X-ray findings are consistent with the histopathologic stage of degeneration. Early changes consist of mild joint space narrowing and minimal osteophyte formation （“spurring”）。 of the periphery of involved joints. More advanced disease is manifested by severe joint space narrowing， marked osteophyte formation at the joint margins， dense sclerosis of subchondral bone， and subchondral cysts. Subluxation and joint space narrowing are often apparent only on weight-bearing films， which should be obtained for both knees and hips.]

　Treatment

　　a. External Support Measures： Management of osteoarthritis depends upon the stage of disease. When degeneration in a weight-bearing joint is mild， symptoms are significantly relieved by use of external supports such as a cane， crutches， or a walker. Though actual healing of osteoarthritic cartilage is difficult to demonstrate， remission of joint pain is sometimes dramatic when stress is diminished by use of external aida.

　b. Medication： Anti-inflammatory drugs are less effective in osteoarthritis than in rheumatoid arthritis or gout. A trial of nonsteroidal antiinflammatory drugs is warranted， however， as some patients report considerable relief with their use. Analgesics， hot packs， ultrasound， and massage may also provide symptomatic relief. Physical therapy for joint strengthening exercises may occasionally by warranted， and weight reduction is beneficial.

　c. Surgical Treatment： Joint arthroplasty has revolutionized the management of severe and disabling osteoarthritis. Pain can be reliably eliminated in most patients with hip or knee joint disease， and improvement in joint motion is generally achieved. Because the cemented prosthetic components often loosen over decades of use， total joint arthroplasty has the longest-lasting results in older， less active individuals.

Persons in the fifth and sixth decades may benefit from osteotomy， particularly when arthropathy is moderate. Following surgical realignment of a joint， the load upon the joint may be shifted toward less severely damaged cartilage. Several years of serviceable joint function may be achieved. Joint replacement may be performed later if required， and the likelihood of component failure will be proportionately diminished.