二十六难曰∶经有十二，络有十五。余三络者，是何等络也？然有阳络，有阴络，有脾
之大络。阳络者，阳跷之络也；阴络者，阴跷之络也，故络有十五焉。
滑氏曰∶直行者谓之经，傍行者谓之络。经犹江汉之正流，络则沱潜之支派，每经皆有
络，
十二经有十二络。如手太阴属肺络大肠，手阳明属大肠络肺之类。今云络有十五者，以其有
阳跷之络，阴跷之络，及脾之大络也。阳跷阴跷，见二十八难，谓之络者，盖奇经既不拘于
十二经，直谓之络亦可也。脾之大络，名曰大包，出渊液三寸，布胸胁其动应衣，脉宗气也
。四明陈氏曰∶阳跷之络统诸阳络，阴跷之络能统诸阴络，脾之大络，又总统阴阳诸络，由
脾之能溉养五脏也。
二十九难曰∶奇经之为病何如？然阳维维于阳，阴维维于阴，阴阳不能自相维，则怅然
失志
，溶溶不能自收持。阳维为病，苦寒热，阴维为病，苦心痛。阴跷为病，阳缓而阴急，阳
跷
为病，阴缓而阳急，冲之为病，逆气而里急。督之为病，脊强而厥。任之为病，其内苦结，
男子为七疝，女子为瘕聚。带之为病，腹满，腰溶溶若坐水中。此奇经八脉之为病也。
滑氏曰∶此言奇经之病也，阴不能维于阴，则怅然失志，阳不能维于阳，则溶溶不能自
收持
。阳维行诸阳而主卫，卫为气，气居表，故苦寒热。阴维行诸阴而主荣，荣为血，血属心，
故苦心痛。两跷脉病在阳则阳结急，在阴则阴结急，受病者急，不病者自和缓也。冲脉从关
元至咽喉，故逆气里急。督脉行背，故脊强而厥。任脉起胞门行腹，故病苦内结，男为七疝
，女为瘕聚也。带脉回身一周，故病状如是，溶溶、无力貌。此各以其经脉所过而言之，自
二十七难至此，义实相因，最宜通玩。
第二十六难说：经脉有十二条，络脉有十五条。多出来的这三条络脉，是什么络脉呢？回答说：有阳跷之络，有阴跷之络，有脾之大络。所谓阳络，就是阳跷脉的络脉；所谓阴络，就是阴跷脉的络脉，所以络脉共有十五条。
滑寿（滑氏）说：直行的称为经，旁行的称为络。经就像长江、汉水的正流，络则像沱水、潜水那样的支流，每条经都有络，十二经脉就有十二条络。例如手太阴肺经属肺而络大肠，手阳明大肠经属大肠而络肺等等。现在说络脉有十五条，是因为其中有阳跷之络、阴跷之络以及脾之大络。阳跷和阴跷在第二十八难中已有论述，称它们为络，大概因为奇经八脉不受十二正经的约束，直接称之为络也可以。脾的大络，名叫大包，出于渊液穴下三寸，分布于胸胁部，其搏动可见于衣服之下，是宗气汇聚之处。四明的陈氏说：阳跷之络统率所有的阳络，阴跷之络能统率所有的阴络，脾之大络又总领阴阳各络，这是因为脾能灌溉滋养五脏的缘故。
第二十九难说：奇经八脉发生病变会怎样呢？回答说：阳维脉维系诸阳经，阴维脉维系诸阴经，如果阴阳不能互相维系，就会感到惆怅失意，身体软弱无力，不能自我控制。阳维脉发病，痛苦于寒热往来；阴维脉发病，痛苦于心痛。阴跷脉发病，表现为外侧弛缓而内侧拘急；阳跷脉发病，表现为内侧弛缓而外侧拘急。冲脉发病，表现为气逆而上和腹部拘急。督脉发病，表现为脊柱强直和厥逆。任脉发病，内部感觉结滞不通，男子发为七疝，女子发为瘕聚（腹内结块）。带脉发病，表现为腹部胀满，腰部软弱无力，好像坐在冷水里一样。这就是奇经八脉的病变情况。
滑寿（滑氏）说：这里讲的是奇经的病变。阴维不能维系阴经，就会惆怅失意；阳维不能维系阳经，就会身体软弱不能自控。阳维脉行于诸阳经而主司卫气，卫气属于气，居于体表，所以痛苦于寒热症状。阴维脉行于诸阴经而主司营血，营血属于血，血归属于心，所以痛苦于心痛。两跷脉发病，病在阳分则阳侧拘急，病在阴分则阴侧拘急，受病的部位拘急，未受病的部位自然弛缓。冲脉从关元穴上行至咽喉，所以出现气逆和腹部拘急。督脉行于背部，所以出现脊柱强直和厥逆。任脉起于胞门（子宫），行于腹部，所以发病时内部感觉结滞，男子发为七疝，女子发为瘕聚。带脉环绕身体一周，所以病症表现如此，“溶溶”形容无力的样子。这些都是根据各经脉循行所经过的部位而言的，从第二十七难到这里，义理相互关联，最适合通篇研读。
Difficulty 26 states: There are twelve primary meridians (Jing) and fifteen collaterals (Luo). What are the three extra collaterals? The answer is: there is the collateral of Yang Qiao, the collateral of Yin Qiao, and the great collateral of the Spleen. The "Yang collateral" refers to the collateral of the Yang Qiao meridian; the "Yin collateral" refers to the collateral of the Yin Qiao meridian; thus, there are fifteen collaterals in total.
Hua Shou (Master Hua) stated: Those that run straight are called meridians (Jing), while those that branch off are called collaterals (Luo). Meridians are like the main streams of the Yangtze and Han rivers, whereas collaterals are like the tributaries such as the Tuo and Qian rivers. Each meridian has a collateral; therefore, the twelve primary meridians have twelve collaterals. For instance, the Hand Taiyin Lung Meridian belongs to the Lung and connects with the Large Intestine, while the Hand Yangming Large Intestine Meridian belongs to the Large Intestine and connects with the Lung, and so on. The statement that there are fifteen collaterals arises because there are the collateral of Yang Qiao, the collateral of Yin Qiao, and the great collateral of the Spleen. As mentioned in Difficulty 28, Yang Qiao and Yin Qiao are considered collaterals because the Extraordinary Vessels are not constrained by the twelve primary meridians, so it is acceptable to refer to them directly as collaterals. The great collateral of the Spleen is named Dabao (SP21), originating three cun below Yuanli (GB24), distributing across the chest and hypochondrium, with its pulsation visible through clothing, representing the gathering point of Zong Qi (Pectoral Qi). Chen from Siming stated: The collateral of Yang Qiao governs all yang collaterals, and the collateral of Yin Qiao governs all yin collaterals. The great collateral of the Spleen further commands both yin and yang collaterals, due to the Spleen's ability to irrigate and nourish the five zang organs.
Difficulty 29 asks: How do diseases of the extraordinary vessels manifest? The answer is: Yang Wei (Yang Linking Vessel) links the yang meridians, and Yin Wei (Yin Linking Vessel) links the yin meridians. If yin and yang cannot mutually link, one feels despondent and loses spirit, and the body becomes flaccid and unable to control itself. When Yang Wei is diseased, the patient suffers from alternating chills and fever. When Yin Wei is diseased, the patient suffers from heart pain. When Yin Qiao is diseased, the yang side is flaccid while the yin side is tense; when Yang Qiao is diseased, the yin side is flaccid while the yang side is tense. When Chong (Penetrating Vessel) is diseased, there is rebellious qi and abdominal tension. When Du (Governing Vessel) is diseased, there is stiffness of the spine and cold extremities (jue). When Ren (Conception Vessel) is diseased, there is internal knotting; in men, this manifests as seven types of hernia (Qi Shen); in women, it manifests as mass accumulation (Jia Ju). When Dai (Belt Vessel) is diseased, there is abdominal fullness, and the waist feels weak and flaccid, as if sitting in water. These are the diseases of the eight extraordinary vessels.
Hua Shou (Master Hua) stated: This passage discusses diseases of the extraordinary vessels. If Yin Wei cannot link the yin, there is despondency; if Yang Wei cannot link the yang, there is flaccidity and lack of self-control. Yang Wei travels through the yang meridians and governs Wei Qi (Defensive Qi). Since Wei Qi is qi and resides in the exterior, disease here manifests as chills and fever. Yin Wei travels through the yin meridians and governs Ying Qi (Nutritive Qi). Since Ying Qi is blood and blood is associated with the Heart, disease here manifests as heart pain. Diseases of the two Qiao vessels: if affecting yang, yang becomes tense; if affecting yin, yin becomes tense. The affected side becomes tense, while the unaffected side remains relaxed. The Chong vessel rises from Guanyuan (CV4) to the throat, hence rebellious qi and abdominal tension. The Du vessel runs along the back, hence spinal stiffness and jue. The Ren vessel originates at the Bao Men (uterus/womb) and runs along the abdomen, hence internal knotting, hernia in men, and masses in women. The Dai vessel encircles the body once, hence these symptoms; "rong rong" describes a state of weakness. All these descriptions are based on the pathways traversed by the respective meridians. From Difficulty 27 to here, the principles are interconnected and should be studied comprehensively.