马关节镜的研究进展

1、马关节镜的研究进展272-280滑膜结构关节镜的选择几乎所有的滑膜结构都可以使用关节镜进行探查。这证明了小型的关节镜现在可以使用，并且能提供高质量的图像。对很小的关节和滑膜结构探查的实现能进一步增强医生的诊断能力，因为通常要在做出诊断或确立预后之后才能进行直接探查。远端指间关节（蹄关节）蹄关节的背面和掌面/跖面的入路已有所报道。背侧入路的建立是为了检查和摘除小的伸肌突起片段，以及移除外伤导致的中节指骨远端的碎片。尽管关节内的可见度有限，但还是可以看见指骨末端关节缘的背侧，也能看见中节指骨关节面的近背侧。通过对关节镜进行调节也可以看见中节指骨远端髁部的关节缘。直径2.7mm的关节镜适用于进入背侧

2、的空腔，尤其适用于小型动物或幼龄动物。而直径4.0mm的能较为容易地进入成年动物的关节内。马仰卧保定，先用10-15ml的乳酸林格溶液扩张关节。在距蹄冠2cm左右、距背侧中线1.5-2cm左右处做关节镜入口。入口可以是常规的穿刺切口，但使用尖锐的套管针有助于穿透纤维关节囊。由于经常会发生滑膜增生，鉴别碎片变得很困难。电动削刨器有助于提高碎片清晰度，在治疗时也可能会用到滑膜切除术。据Boening等人报道，在摘除伸肌突起片段的21匹马中，有19匹效果良好，手术后2-10周便陆续恢复了工作能力。蹄关节的掌面/跖面入路也有报道。尽管这方面的关节入路在临床上很少见，但对于舟状骨骨折的评估、中节指骨或远

3、节指骨的某些罕见骨折、一些穿透创、关节的彻底灌洗以及对患有脓毒症的关节实施滑膜切除术这些方面是有用的。马侧卧保定，用前面提到的方法扩张关节。刚沿轴到达侧支软骨掌面/跖面末端附近就可以明显感到掌面/跖面的扩张。沿轴向神经血管束处做一穿刺口，随着远侧肢体最大程度的拉伸，使用尖头套管针可以使关节镜的套管到达蹄楔部的顶点。一旦纤维囊被穿透，锥形球头穿刺针便可用于关节的最终定位。4mm的关节镜很容易便可以进入该关节腔中。 舟状骨的背侧、中节指骨的远端关节面附近、远节指骨关节面最近处（关节扩张到最大时）以及籽骨侧韧带的边缘处都可以看到。外侧的关节囊比内侧的关节囊大，这使得外侧入路比较简单。已有人提出用这种

4、技术可以实现籽骨侧韧带切开术，但具体细节还没有确定。近端指间关节（系部）系关节的关节镜检查很少见，但是有关于摘除中节指骨近端关节面处由于外伤或发育导致的碎片的报道。第一作者在直径2.7mm关节镜的视野下的自近节指骨外侧移除了一大块外伤造成的碎片，且明确了在成年马的关节脓毒症灌洗和滑膜切除术中是完全可以使用4.0mm关节镜的。关节入口和视野范围与蹄关节背侧入路是一样的。在做切口需要扩张前关节，以保证关节镜在关节中进入的足够远，直至能够看见中节指骨的近端。有报道指出在该处进行关节镜手术后会出现关节囊纤维增生。 肘关节就关节总量而言，肘关节属于大关节。然而关节镜进入肱桡关节是受到限制的，尽管可以很容

5、易进入肱桡关节近端外侧大的穹窿中，但这一点在临床上是没有意义的。读者可以通过查阅一些原始文献来了解关节镜和器械进入关节的详细位置。需要注意的是，血管神经的位置使得从内侧进入肱桡关节变得更加复杂，这点和人肘关节的情况是一样的。也有报道指出，70°的关节镜可用于检查大部分关节头端表面的。Nixon也发现，背侧卧适用于在同一病例身上做内、外侧两个切口的情况。然而，肘关节是比较难做关节镜入口的关节之一，笔者建议在接触临床病例之前，应先采用将标本背侧卧的方法来熟悉该关节。在临床上，采用这种关节镜手术入路的主要是涉及到肱骨或桡骨外侧的囊性病变的病例。使用内侧入路能充分暴露肱骨髁，有利于进行肱骨病

6、变清创术，但即便使用了断裂牵引器来分离关节，这种方法也无法进入径向骨髁病变部位。侧面入路更容易完成，并且神经血管损伤的风险更小，但临床上对肱桡关节部分产生严重影响的情况是很少见的。通过三头肌的近端入路也比较容易完成，并且可以看到部分肱骨上髁、尺骨的近端部（包括肘凸的关节部）和部分指深屈肌。该方法已被证明可应用于尺骨鹰嘴的感染性病灶清除术中。髋关节马髋关节的诊断以及潜在的治疗性用途已有了两种独立的评估方法。所研究对象为马驹，也有对成年马进行研究的。这两项研究使用的都是标准的4mm关节镜。马侧卧保定，用16或18号的15cm脊髓穿刺针（或16号静脉导管的针鞘）穿刺进入关节，并注入液体使其扩张。马驹

7、的关节的扩张需要25ml的液体，成年马则需要60ml。尽管Nixon认为70°的关节镜能提高对股骨头内外侧大部分区域评估的准确度，但在大部分病例中，使用4mm关节镜和套管系统就可以提供足够的视野。成年马需要使用更长的关节镜(Storz公司)是因为常规关节镜的长度是有限的。对于体重超过300kg的马来说，需要准备更长的骨钳、刮匙和套管设备。让马的后肢外展可以使股骨头和髋臼分开，增加了股骨头韧带部、股骨头、髋臼关节面和非关节面的可视程度。内收和转动四肢可以增加马驹股骨头外侧面的可视程度。具有里程碑意义的关节镜入口是在大转子的内外侧突起间可以触摸到的凹陷处。用带有尖头套管针的关节镜自内侧沿

8、股骨颈向下轻轻刺入关节。最终进入关节时要替换成球头穿刺针。最常用的器械口在关节镜入口前2-6cm处及其后1-2cm处。有时为了接近关节最末端还需要做第二个内侧入口。在临床上，关节镜已可以用来检查包括股骨头韧带撕裂、股骨头或髋臼骨软骨病、骨关节炎和髋臼缘骨折。股胫关节末端虽然股膝关节和股胫关节的前端都很适合关节镜的进入，但用关节镜和仪器进入在股胫关节的末端处仍是很大的挑战。1992年Stick等人介绍了一种末端入路的方法，从股胫关节外侧摘除了关节骨软骨碎片。此后不久，Hance等人进一步描述了从内侧和外侧通路进入股胫关节内外侧末端关节囊的方法，用以对股骨髁部分的感染性或渐进性骨科疾病进行治疗。在

9、所描述的方法中用到了大体解剖、计算机断层扫描技术、X光透视技术和关节镜检查，Trumble等人确定了这些关节囊的解剖位置，并提出了关节镜和器械进入的一些建议。读者可以参考这些论文中有关解剖学位置的细节，因为这些文章的图片和图表会大大有助于对解剖位置的学习以及对手术方法的理解。大部分股骨髁处的清晰化视野已经能够实现，如同半月板周围的非关节部分一样。进入胫骨的近端部分是非常受限的。末端关节囊被腘肌的肌腱分为近侧和远侧囊，在进入关节前必须考虑到这一点，因为这两个囊需要各自不同的进入方法。然而，临床上进入近端关节囊前需要治疗大部分可视性病变。正如前面提到的那样，从末端进入的难度要远远超过从膝关节头端进

10、入。此外，临床上涉及到关节末端的情况要远远少于头端，导致这些方面的手术（及实践）很少能够完成。要让这些方法变得更易进行，必须要经过相当多的练习。几种主要的术后并发症都与这些关节囊的手术方法有关，如果太过于靠近末端可能会损坏腓总神经。内侧和外侧的关节囊是彼此分开的，且两个囊袋之间隔膜的渗透可能会导致腘动脉或静脉的裂伤，这可能导致十分严重的后果。末端十字韧带处于两个空腔之间一个额外的位置。其部分轮廓在中隔的滑膜下可以看到，但如果滑膜是完整的，便不可能直接看到。指部腱鞘尽管超声检查的结果对于肌腱和腱鞘来说是非常有意义的，但对这些结构进行内镜检查（内窥镜检查），有时更能进一步提供信息。某些增生性滑膜病

11、变已经能用内窥镜进行彻底诊断 ，内窥镜辅助下的环状韧带横断技术也已被报道。内窥镜也可以用于滑膜切除术，以及在病例指部腱鞘感染时除去纤维蛋白。马仰卧或侧卧保定，使用标准关节镜设备。向指部腱鞘内注入20-30ml液体使其膨胀，目的是在下肢的掌面/跖面创造出“泡沫”或膨胀感，尤其是在籽骨远端和神经血管束的末端。在膨胀处做皮肤切口，这标志着镜头进入的位置已经被确定。套管的位置是固定的，靠近或倾斜朝向腱鞘对侧的位置。这种方法通常会将套管末端置于指浅屈肌腱和指深屈肌腱之间，偶尔会在指深屈肌腱和籽骨远端韧带之间。利用球节弯曲，关节镜可以直接通过球节管，但大部分指部腱鞘近端位置完整视野的获得还需要做第二个开口

12、，将关节镜转移到该开口处。虽然进入腱鞘相对比较容易，但我们仍建议外科医生通过对尸体四肢进行解剖实践来熟悉屈肌腱和滑膜附件的解剖特点。腕管源自远端桡骨骨骺残余部附近的骨软骨瘤偶尔会扩散进入腕管，还会对滑膜和（或）屈肌腱造成刺激（腕管综合征）。虽然可以直接做腕管处切口来摘除骨软骨瘤，但Squire等人最近介绍了一种在关节镜引导下摘除骨软骨瘤的方法。他们采用内侧入路的方法，将关节镜进入的切口设在屈肌腱鞘上方2cm处，靠近桡骨远端骨骺水平线位置。在距离关节镜入口2cm处做一个操作口，通过它将骨软骨瘤取出。据报道视野是很清晰的。最近，腕管处的外侧入路方法已被报道，同样能提供清晰的视野以及切除病灶的通路。

13、关节镜入口设在靠近桡骨远端骨骺水平线3cm处，在尺骨外侧肌和指外侧伸肌腱之间。通常不需要提前扩张腱鞘，用腕部的力量将球头穿刺针轻轻刺入。操作孔设在距离关节镜入口2cm处。二头肌和跟骨粘液囊笔者并不了解关节结构描述的方法。但是，它们都能够被探查，用以进行滑膜切除术或经影像学检查诊断为溶骨性破坏的清创术（Gary Baxter，个人通讯，1995年）。三角定位技术被用于确定进针的位置，以引导其他仪器进入恰当的位置。Advances in Equine ArthroscopyArthroscopy of Selected Synovial StructuresVery few synovial st

14、ructures remain that have not been explored using an arthroscope. This attests to the small size of the arthroscopes now available and to the high-quality images they can produce. The ability to explore even small joints and synovial structures further increases the diagnostic abilities of the clini

15、cian, because direct visualization is often required to make or confirm a diagnosis or to establish a prognosis. Distal Interphalangeal (Coffin) JointApproaches to both the dorsal and palmar/plantar surfaces of the coffin joint have been described. The dorsal approach was developed for evaluation an

16、d removal of small extensor process fragments, and removal of a traumatically induced fragment from the distal aspect of the middle phalanx has also been reported. Although visibility in his joint is limited, the dorsal articular margin of the distal phalanx can be seen, as can the dorsoproximal art

17、icular surface of the middle phalanx. The arthroscope can be maneuvered so that the margins of the distal condyles of the middle phalanx can also be seen. A 2.7-mm diameter arthroscope is useful for entry into the dorsal compartment, particularly in small or young animals. However, the 4. 0-diameter

18、 can be placed relatively easily into adult joints. The horse is placed in dorsal recumbency and the joint is initially distended with 10 to 15 mL of lactated Ringer's solution. Entry for the arthroscope and instruments is 2-cm proximal to the coronary band and 1.5 To 2-cm lateral to the dorsal

19、midline. A routine stab incision is made for arthroscope entry, but use of the sharp trocar can also help to gain initial penetration of the fibrous joint capsule. Identification of fragments can be difficult because synovial membrane hypertrophy is often excessive. A motorized resector is extremely

20、 useful in improving fragment visualization, and synovectomy is also probably therapeutically indicated. Boening et a1 reported favorable results in 19 of 21 horses after extensor process fragment removal, with return to work ranging from 2 to 10 weeks after surgery. Approaches to the palmar/plantar

21、 aspect of the coffin joint have also been described. Although clinical involvement of this aspect of the joint is rare, evaluation could be useful in certain navicular bone fractures, unusual fractures of the middle or distal phalanx, certain penetrating wounds, and for complete joint lavage and sy

22、novectomy for joint sepsis. Horses are placed in lateral recumbency and the joint is distended as previously described. Palpable distention of the palmar/plantar aspect of the joint can be felt just axial to the palmaroproximal/plantaroproximal end of the collateral cartilage. A stab incision is mad

23、e just axial to the neurovascular bundle, and with the distal limb maximally extended and using the sharp trocar the arthroscope cannula is directed toward the apex of the frog. Once the fibrous capsule is penetrated, the conical obturator is used for final joint positioning. The 4-mm arthroscope ca

24、n be readily placed into this joint space. The dorsal aspect of the navicular bone, the proximal portion of the distal articular surface of the middle phalanx, and the very proximal surface of the distal phalanx (with maximal joint distention) can be seen, as can the edge of the collateral sesamoide

25、an ligaments (Fig. 6). The lateral joint pouch is larger than the medial pouch, making lateral entry easier. The potential for desmotomy of the collateral sesamoidean ligament using this technique has been suggested, but details remain to be determined. Proximal Interphalangeal (Pastern) JointArthro

26、scopy of the pastern joint is rare but has been reported for removal of traumatically or developmentally induced fragments that originate from the proximal surface of the middle phalanx. The first author has also removed a large traumatically induced fragment from the distomedial aspect of the proxi

27、mal phalanx under visualization using the 2.7-mm diameter arthroscope, and is aware of lavage and synovectomy for joint sepsis completed using a 4. 0-arthroscope in an adult horse (Gary Baxter, personal communication, 1995). Joint entry and extent of visualization are similar to that for the dorsal

28、aspect of the coffin joint. The joint should be distended before portal placement to ensure that the arthroscopic portal is sufficiently distal in the joint to allow visualization of the proximal margin of the middle phalanx. Fibrous thickening of the joint capsule has been reported after arthroscop

29、ic surgery on this joint. Elbow JointThe elbow joint is a large joint in terms of its total joint volume. However, arthroscopic access to the humeroradial articulation is limited, and although the large proximolateral cul de sac of the humeroulnar articulation can be readily entered, little of clini

30、cal significance affects this site. The reader is referred to the original article for details of joint landmarks relative to arthroscope and instrument access. Note, however, that the location of neurovascular structures makes the caudomedial approach to the humeroradial articulation more complicat

31、ed, a situation similar to that of the human elbow. The 70-degree arthroscope was also reported to be useful in the evaluation of the most craniomedial surfaces of the joint. Nixon also found dorsal recumbency to be useful if performing both lateral and medial approaches on the same patient. However

32、, the elbow is one of the more difficult joints for which to gain arthroscopic access, and the authors suggest that a lateral recumbency approach using cadaver specimens be used to gain familiarity with this joint before clinical cases are attempted. The major clinical entity that might be considere

33、d for arthroscopic surgery using this approach is cystic lesions involving the distomedial aspect of the humerus or radius. Exposure of the humeral condyle using the caudomedial approach is adequate for humeral lesion debridement, but access to radial condyle lesions is impossible, even when fractur

34、e distractors have been used to distract the articulation. The craniolateral approach is easier to complete and carries less risk of neurovascular damage, but clinically important conditions affecting this part of the humeroradial articulation are rare. The proximocaudal approach through the triceps

35、 muscle is also relatively easy to complete and allows visualization of a portion of the humeral epicondyle, the proximal portion of the ulna (including the articular portion of the anconeal process), and a portion of the deep digital flexor tendon. This approach has proven useful in debriding a foc

36、al septic lesion involving the anconeal process of the ulna. HipTwo independent studies evaluated approaches to the equine hip for diagnostic and potentially therapeutic purposes. One study involved foals, the other study also included mature horses. In both studies, a standard 4-mm arthroscope was

37、used. Horses were placed in lateral recumbency and the joint was distended with fluid administered through a 16-or 18-gauge, 15-cm spinal needle (or the needle stylet from a 16-gauge IV catheter). Foal joints were distended with 25 mL of fluid, adult joints required 60 mL of fluid. A standard 4-mm a

38、rthroscope and cannula system proved adequate for visualization in most cases, although Nixon did determine that the 70-degree arthroscope improved assessment of the most craniomedial and caudomedial aspects of the femoral head. A longer arthroscope (Storz) is useful in adult horses because the surg

39、eon is working at the length limits of the regular arthroscopes. Longer rongeurs, curettes, and egress cannulae instruments were also deemed essential in horses weighing more than 300 kg. Distraction of the limb separated the femoral head from the acetabulum and improved visualization of the ligamen

40、t of the head of the femur, the head of the femur, and the articular and nonarticular surfaces of the acetabulum. Adduction and rotation of the limb improved visualization of the craniomedial and. caudomedial surfaces of the femoral head in foals. The landmark for arthroscopic entry is the palpable

41、notch between the cranial and caudal prominences of the greater trochanter. The arthroscope cannula with sharp trocar should be directed slightly cranial and downward to course along the femoral neck toward the joint. Replacement with the conical obturator is done before final joint entry. The most

42、useful instrument portal is placed 2 to 6 cm cranial and 1 to 2 cm distal to the arthroscope portal. Occasionally, a second caudolateral portal is required for access to the most caudal aspects of the joint. Clinical entities that have been evaluated arthroscopically have included tearing of the lig

43、ament of the head of the femur, osteochondrosis of the head of the femur or acetabulum, osteoarthritis, and rim fracture of the acetabulum.Caudal Aspects of the Femorotibial JointsAlthough the cranial aspects of the femoropatellar and femorotibial joints have been well characterized arthroscopically

44、, the caudal compartments of the femorotibial joints present a greater challenge to arthroscope and instrument access. In 1992 Stick et a1 described a caudolateral approach used to remove an osteochondral fragment from the lateral femorotibial joint.Shortly thereafter, Hance et al further described

45、both medial and lateral approaches to the caudal pouches of the medial and lateral femorotibial joints used in the treatment of infectious or developmental orthopedic conditions affecting this portion of the femoral condyles. In a descriptive approach using gross dissection, computed tomography, flu

46、oroscopy, and arthroscopy, Trumble et al precisely defined anatomic limits for these pouches and made suggestions for arthroscopic and instrument access.The reader is referred to these papers for details concerning anatomic landmarks, because the drawings and figures in these articles greatly assist

47、 in learning the regional anatomy and understanding the surgical approaches. Good visualization of large portions of the femoral condyles can be realized, as can the peripheral nonarticular portions of the menisci (Fig. 7). Access to the proximal aspect of the tibia is extremely limited. The caudola

48、teral pouch is also divided into a proximal and a distal pouch by the tendon of the popliteus muscle, which must be taken into consideration before joint entry because a separate approach is required for both pouches. However, entry into the proximal pouch is required to treat most lesions seen clin

49、ically.As previously mentioned, access to the caudal pouches is considerably more difficult than that to the cranial aspects of the stifle joint. Furthermore, clinical involvement of the caudal aspects of the joint is much less frequent than that of the cranial aspects, which results in less frequen

50、t surgery (and therefore practice) being completed in these areas. Considerable practice is necessary to become comfortable using these approaches.Few major complications are associated with the surgical approaches to these pouches, although too-caudal placement of the caudolateral portal could dama

51、ge the common peroneal nerve. The medial and lateral pouches are separate from one another, and penetration of the septum between the two pouches could result in laceration or tearing of the popliteal artery or vein, which could be disastrous. The caudal cruciate ligament lies in an extrasynovial lo

52、cation between the two compartments. Part of its outline can be visualized beneath the synovial membrane at the septum, but direct visualization is impossible if the synovial membrane is intact.Digital Tendon SheathAlthough ultrasonography is invaluable in evaluation of tendons and tendon sheaths, e

53、ndoscopic evaluation of these structures (tenoscopy) sometimes provides further information. Certain proliferative synovial lesions have been more completely evaluated with tenoscopy, and an endoscopically assisted annular ligament transection technique has also been described. Tenoscopy can also be

54、 useful for synovectomy and fibrin removal in selected cases of digital sheath infections.Horses can be positioned in either dorsal or lateral recumbency, and standard arthroscopic equipment is used. The digital sheath is distended with 20 to 30 mL of fluid, which creates a "bubble" or out

55、pouching on the palmar/plantar surface of the limb just distal to the sesamoid bones and just caudal to the neurovascular bundle. A skin incision is made over this outpouching, which marks the site for scope entry. The sleeve is placed routinely and is directed proximally and obliquely toward the op

56、posite wall of the sheath. This approach usually places the end of the cannula between the superficial and deep digital flexor tendons (Fig. 8) and occasionally between the deep digital flexor tendon and the distal sesamoidean ligaments. With the fetlock flexed, the arthroscope can be directed proximally through the fetlock canal, but complete visualization of the most proximal aspect of the digital sheath requires placement of a second portal proximally and transfer of the arthroscope to this portal.