POPLITEAL SPACE [fossa poplitea (PNA, JNA, BNA)] — the kostnofastsialny receptacle located in back area of a knee between the lines which are conditionally carried out 8 cm above and on as much below epicondyles of a femur, containing cellulose, vessels, nerves and lymph nodes.
On an extremity, halfbent in a knee joint, at a muscle tension of P. I. has the form of a rhombus (fig.) limited from above and outside to a sinew of a biceps of a hip (m. biceps femoris), from above and from within sinews of a semimembranous muscle (m. semimembranosus) and the semitendinous muscle (m. semitendinosus) lying more superficially, from below and outside of lateral, and from below and from within medial heads of a gastrocnemius muscle (m. gastrocnemius). P.'s bottom I. make: higher than the line of a joint — the subnodal surface of a femur (facies poplitea), a knutra from it lies a big adductor (m. adductor magnus), knaruzh — a biceps of a hip; lower than the line of a joint — the back wall of the capsule of a knee joint and condyles of a tibial bone covered with a slanting subnodal sheaf (lig. popliteum obliquum) and subnodal muscle (m. popliteus.) Behind P. I. it is limited to own fascia passing from muscles of a hip to muscles of a shin, on each side — fascial cases of muscles (tsvetn. fig. 1).
P.'s skin I. thin, on it two or three folds are well-marked, from to-rykh lower corresponds to the line of a joint. In skin there are sweat and sebaceous glands, indumentum is expressed poorly. Skin is innervated back and lateral by cutaneous nerves of a hip (nn. cutanei femoris posterior et lateralis) and hypodermic nerve (n. saphenus). B to hypodermic cellulose pass a venous anastomosis between big and small saphenas of a leg (vv. saphenae magna et parva) and branches of cutaneous nerves. Own fascia of P. I. dense, transparent. In the channel formed by splitting of a fascia between heads of a gastrocnemius muscle (Pirogov's channel) there passes the small saphena of a leg, edges falls into a subnodal vein, and a medial cutaneous nerve of caviar. Being split on two leaves (superficial and deep), and then again merging, the fascia forms fascial vaginas for muscles and a neurovascular bunch. The cellulose filling P. I., it is connected with cellulose of fascial beds of a hip and shin. In it there are subnodal artery and a vein (and. et v. popliteae), tibial and the general fibular nerves (nn. tibialis et peroneus communis), their skin and muscular branches (tsvetn. fig. 2).
Subnodal vessels pass in a fascial case which is connected by spurs with fascial cases of muscles and sciatic nerve (see). In an upper third of P. I. subnodal vessels are located between big bringing and on l at webby muscles, in average — in cellulose between the subnodal surface of a femur and own fascia, knaruzh from a sinew of a nolu-webby muscle, in the lower third they lie on a subnodal muscle and are covered with edges of heads of a gastrocnemius muscle. A popliteal artery in the lower and average third of P. I. gives medial and lateral upper knee arteries (aa. genus superiores medialis et lateralis), average knee (. genus media), lateral and medial lower knee arteries (aa. genus inferiores medialis et lateralis). The first three arteries go above the line of a joint, and two last — below; they anastomose among themselves and participate in formation of knee joint network (rete articulare genus). The subnodal vein is formed of tibial and fibular veins at the level of a knee joint and passes behind an artery.
The sciatic nerve (n. ischiadicus) shares on tibial and the general fibular nerves, most often in an upper corner of P. I. A tibial nerve in an upper and average third of P. I. lies knaruzh from subnodal vessels, and in lower — behind them; here in the direction behind the nerve, a vein, an artery beforehand are located. The tibial nerve gives a medial cutaneous nerve of caviar (n. cutaneus surae medialis) and muscular branches. The general fibular nerve passes on an inner edge of a biceps of a hip, gives a lateral cutaneous nerve of caviar (n. cutaneus surae lateralis), then bends around a sinew of a biceps of a hip and a head of a fibular bone, probodat a back intermuscular partition and gets into a bed of fibular muscles between a bone and a long fibular muscle (upper muscular malober-tsovy the channel — canalis musculopero-neus superior) where is divided into superficial and deep fibular nerves (nn. peronei superficialis et profundus) and muscular branches.
Superficial limf, vessels accompany inflows of big and small saphenas of a leg and fall in superficial subnodal and inguinal limf, nodes, and deep accompany arteries and fall in deep subnodal, inguinal and outside ileal limf. nodes. Subnodal limf, nodes (usually there are 2 — 4 nodes) most often are located along subnodal vessels.
Item I. borders from the inside on epicondylic and podmy-shchelkovy poles (tsvetn. fig. 3) through which quick access to a neurovascular bunch from internal department of P. is possible I. The epicondylic pole (Zhober's pole) is limited in front of big to the bringing muscle of a hip (m. adductor magnus), behind semimembranous, semitendinous and thin (m. gracilis) muscles, from below a medial condyle of a femur and from above a sartorial muscle (m. sartorius). The subcondylar pole is located between a medial head of a gastrocnemius muscle and a tibial bone.
Injuries of area P. I. happen closed and opened, to damage or without damage of a neurovascular bunch. Damages with disturbance of an integrity of a neurovascular bunch are especially heavy.
Without damage of a neurovascular bunch treat the closed injuries hurt (see), stretching (see. Distortion ) and gap (see) the fabrics limiting P. I. The closed P.'s damages I. with disturbance of an integrity of a neurovascular bunch usually accompany heavy damages knee joint (see) — to lobbies and posterior dislocations, changes of the distal end femoral or proximal end of a tibial bone, to sprains of a joint. The closed damages of vessels and nerves during the falling of weight on area P. I are possible., and also (in rare instances) at sharp and sudden extension of an extremity.
At the closed damage of a neurovascular bunch, especially popliteal artery, symptoms of interstitial bleeding are most expressed. In P. I. the dense, intense, quite often pulsing swelling is defined, over a cut at auscultation noise are heard; usual contours of P. I. are broken and characteristic outlines of a rhombus are erased. Even at incomplete (side, pristenochny) the injury of an artery which is not breaking its passability quickly there come heavy disorders of circulation. P.'s capacity I. it is small, its walls are a little pliable therefore the accruing hematoma soon squeezes at first a subnodal vein, then the injured artery. Consistently cyanosis and puffiness of foot and distal third of a shin develop, easing and disappearance of a peripheric pulse, a cold snap of an extremity is noted. The prelum of nerves causes sharp pains, sensitive and motive frustration. At a complete cross separation of an artery signs of disturbance of its passability appear immediately. The closed damages of vessels of P. I. lead to ischemic gangrene or, at a favorable current, to formation of false aneurism.
Wounds of area P. I belong to open injuries without damage of a neurovascular bunch., received most often in life, on production, etc. (see. Wounds, wounds ). Open damages of subnodal vessels and nerves arise, as a rule, as a result of use of firearms. According to S. A. Rusanov, gunshot wounds of a popliteal artery in the period of the Great Patriotic War took the third place among wounds of other large arteries of extremities. Approximately in half of cases along with an artery also the vein whereas simultaneous damage of nervous trunks met only occasionally was injured, but more often than at wound of any other vessel of the lower extremity. Due to rather superficial bedding of a popliteal artery and absence over it powerful muscular layers of its wound wounds of other large vessels of the lower extremity are followed by primary bleeding more often (according to E. V. Smirnov, in 32,5% of cases), than. A possibility of a bystry prelum of vessels as a hematoma and scarcity of collaterals serve as the reason of frequent ischemic necroses in the pool of a popliteal artery after its wound. According to E. V. Smirnova, ischemic gangrene came at 21%, according to S. A. Rusanov — at 26% of wounded with damage of subnodal vessels.
Diagnosis of damages of vessels of P. I. at a research of an extremity (survey, identification of pulse on foot, auscultation in subnodal area) usually comes easy. In doubtful cases resort to angiography (see).
Injury of nerves is demonstrated by sensitive and motive frustration in foot and a shin, these electrodiagnoses, hronaksimetriya (see), etc. At injury of a tibial nerve to P. I. bending of foot and fingers is broken, cultivation and reduction of fingers is lost, patients cannot get up on socks; akhill and bottom reflexes are absent; foot is in the provision of extension (so-called calcaneal foot). Sensitivity on a back surface of the lower third of a shin, a sole and a dorsum of distal phalanxes of fingers is broken, the myshechnosustavny feeling in the IV—V fingers sometimes falls apart; thermalgias are noted. At damage of the general fibular nerve extension stopt and assignment of its knaruzha, and also extension of fingers is broken; foot hangs down — so-called. horse foot (see), the patient cannot lean on a heel; sometimes there are no akhill a reflex. Sensitivity on average department of the back of foot and on the anteroexternal surface of a shin is broken.
Treatment of damages of P. I. depends on that, remained or not an integrity of a neurovascular bunch. In the first case treatment of the closed P.'s injuries I. generally conservative (rest, cold, sublime position of a leg), at an open injury primary is shown surgical treatment of wounds (see). In the second case an operative measure on vessels and nerves is necessary.
Operation is performed after an applying a tourniquet. Surgical accesses to subnodal vessels and a tibial nerve are possible behind and from the inside. At back access the section of skin, hypodermic cellulose and own fascia 15 — 20 cm long make a little otstupya knutr from the longitudinal diagonal of a subnodal rhombus (in order to avoid wound of a small saphena of a leg and a medial cutaneous nerve of caviar). In cellulose P. I. find a tibial nerve in the beginning, also medialny — a subnodal vein is deeper, is even deeper — an artery. At access through Zhober's pole the section (at a halfbent extremity) is carried out on edge of a sinew of a big adductor on 7 — 8 cm up from a medial condyle of a hip. Sinews of sgibatel delay kzad, a sinew of a big adductor of a kpereda (tsvetn. fig. 3). Through friable cellulose enter P. I., where at the bone find an artery, and several kzada from it a vein. Use the back access allowing to open widely vessels and a nerve more often. For an exposure of the general fibular nerve do a section over a sinew of a biceps of a hip up to a head of a fibular bone. Knutri from a section cut a fascia and, going down in depth of a wound on an inner edge of a biceps of a hip, find a nerve in cellulose.
On the damaged popliteal artery (side or circular wound of a vessel without major defect of its wall) impose vascular seam (see) or resort to plastic substitution of defect a vascular transplant (see. Blood vessels , Shunting of blood vessels ). At impossibility to recover a blood stream an artery tie up in a wound or on an extent (see. Bandaging of blood vessels ). According to «Experience of the Soviet medicine in the Great Patriotic War of 1941 — 1945», bandaging of a popliteal artery at fresh wounds in 30% of cases led to gangrene of an extremity. In the conditions of war a positive role was played in this respect by the simultaneous bandaging of the unimpaired subnodal vein (5 — 6 cm above than the level of bandaging of an artery) offered by V. A. Oppel on the basis of the theory of the reduced blood circulation. On materials B. B. Petrovsky, this operation gave the chance to twice lower percent of a gangrenosis.
The injured subnodal vein is tied up that usually is not followed by complications. A stop of bleeding from P.'s wound I. by means of a tampon it is dangerous; the hard tamponade, even at the unimpaired popliteal artery, often leads to ischemic gangrene of an extremity. The damaged nervous trunks need to be sewed.
Diseases. Acute purulent processes in P. I. (phlegmon, abscess, purulent flow) can be a consequence of an adverse course of the opened or closed P.'s injury I. or result of transition of purulent process of surrounding fabrics, and also arise in the lymphogenous way (see. Lymphadenitis , Limfangiit ). At purulent you drive (see) break of a back wall of the capsule of a joint leads to formation of the purulent zatek extending from P. I. in the proximal and distal directions. In the proximal direction flow extend on the cellulose surrounding a sciatic nerve and femoral vessels in distal — on a crack between kambalovidny and sural muscles, in kletchatochny space between a front surface of a soleus muscle and own fascia of a shin, to the golenopodkolenny canal (canalis cruropopliteus), on a back surface of an interosseous membrane on the course of flexor muscles of foot. Distribution of a purulent zatek to P. I is possible. from a hip or a shin. Diagnosis is based on existence of signs of purulent process. Treatment includes opening and drainage of suppurative focuses, use of antibacterial agents and fortifying actions (see. Abscess ; Flow ; Wounds, wounds ; Phlegmon ).
In P. I. the cold abscesses which went down from above (in the presence of primary tuberculous focus in a backbone, a hip joint) or being result of tubercular are occasionally observed gahnite (see). Diagnosis of cold abscesses presents great difficulties if the basic disease is not distinguished. In doubtful cases the puncture with microscopic examination of pus is shown. Treatment of a natechnik shall be connected with treatment of a basic disease (see Tuberculosis extra pulmonary, Natechnik ).
Aneurisms of subnodal vessels are a consequence of an injury more often. According to «Experience of the Soviet medicine in the Great Patriotic War of 1941 — 1945», traumatic aneurisms of a popliteal artery made 10,94% of aneurisms of all vessels. The aneurisms of a popliteal artery developing at diseases of a vascular wall (syphilis, atherosclerosis) are more rare. Clinically aneurisms of a popliteal artery are characterized by existence of the pulsing swelling in P. I., the systolic noise listened or caught at a palpation, trophic disorders of the affected extremity. At arteriovenous aneurisms are observed characteristic constant noise in the area P. I., phlebectasia of a shin and foot, hypostasis and cyanosis of an extremity, not healing ulcers of a shin. P.'s aneurisms I. are subject to operational treatment (see. Aneurism ).
A varicosity in the area P. I. it is observed often. At the same time are surprised a small saphena of a leg (near the place of its falling into a subnodal vein) and its anastomosis with a big saphena of a leg (see. Varicosity ).
So-called serous cysts of P. I. (see. Hygroma ) represent accumulation of synovial fluid in synovial bags (see), proceed it is good-quality. It is difficult to establish the reason of emergence of cysts. At adults emergence them sometimes can be connected with long work standing, and also with this or that inflammatory disease of a knee joint passing to a synovial bag. More often than others, both the cyst of a bag semimembranous muscles occurs at adults, and at children. In the beginning absolutely painless and not breaking function of an extremity cyst in process of growth is shown by dull uncertain ache in the area P. I., in a cut about-ruzhivayut the elastic ovoid tumor disappearing at a muscle tension and easily available to a research at their relaxation. The tumor is easily displaced in transverse direction. Cysts of a bag of a subnodal muscle are very seldom observed. In exceptional cases such cyst leaves from under bottom edge of a subnodal muscle and develops at lateral edge of an upper quarter of a shin. Medial cysts lie in the depth of P. I. but the centerline, they are sometimes multiple, have the small sizes. Some surgeons consider them as hernial protrusions of a synovial membrane of a joint.
Recognition of cysts of P. I. in most cases simply. Diagnosis of medial cysts is complicated. At differential diagnosis it must be kept in mind a possibility of a pulsation of a medial cyst owing to its proximity to blood vessels; on the other hand, the aneurism of a popliteal artery which is not pulsing and not having characteristic noise can be mistakenly taken for a serous cyst. Therefore in doubtful cases resort to X-ray contrast researches (see. Radiodiagnosis ).
The cysts breaking function of an extremity delete in the operational way, in other cases punktirut that slows down their growth and often leads to treatment. Introduction to a cavity of a cyst of the irritating substances is contraindicated since cysts are quite often reported with a cavity of a joint. In this regard operation and a puncture are made only in a hospital at the most strict observance of an asepsis.
Echinococcal cysts of P. I. meet very seldom. The diagnosis is specified by means of a puncture of a cyst and on the basis of results of specific reaction of Kasoni (cm, Echinococcosis ). Echinococcal cysts delete in the operational way.
Tumors. From benign tumors meet more often lipoma (see), fibroma (see. Fibroma, fibromatosis ), more rare chondroma (see) and osteoma (see), and also tumors, coming from nervous trunks, sometimes as display of a disease of Recklinghausen (see. Neurofibromatosis ). The last seldom are the big sizes, are followed by the severe irradiating pains.
From malignant tumors P, I. it is more often observed sarcoma (see), coming from ligaments, muscles, sinews, fastion, is more rare — a carcinoma cutaneum (see), metastasises of tumors from peripheral departments of an extremity. Sarcomas, coming from vessels (see. Angiosarcoma ), are very rare. They are located around the main vessels of P. I., are closely connected with a wall of a vein, but do not sprout it, reach the big sizes, are usually poorly painful. The sarcoma developing in a cover of a nervous trunk quickly leads to an atrophy of nerve fibrils.
Treatment of benign tumors operational, In early stages of sarcoma can give effect a combination therapy — high amputation (see), radiation therapy (see), chemotherapy (see). At a carcinoma cutaneum yields good result roentgenotherapy (see).
Bibliography: Goryachev A. N. and Tursheva I. G. Damages of a popliteal artery, Vestn, hir., t. 120, No. 6, page 122, 1978; Kariyev M. of X., Luzina E. V. and Fayn A. S. «Hernia» of a popliteal space (Becker's cyst), in the same place, t. 124, No. 2, page 105, 1980; To about in An about in V. V. and Travin A. A. Surgical anatomy of the lower extremities, page 352, M., 1963; Maksimenkov A. N. Ways of distribution of purulent processes at gunshot wounds of extremities, M., 1944; Operational surgery and topographical anatomy, under the editorship of V. V. Kovanov, page 62, M., 1978; Experience of the Soviet medicine in the Great Patriotic War of 1941 — 1945, t. 17, page 339, 1953, t. 19, page 349, M., 1955; Travin A. A. A fascia and cellulose of a popliteal space, in book: Surgical anatomy of fastion and kletchatochny spaces of the person, under the editorship of V. V. Kovanov, page 86, M., 1959; Gutzeit R. Bedroh-liche arterielle Arrosious-blutungen in der Fossa poplitea, Zbl. Chir., S. 315, 1952; Lanz T. u. Wachsmuth W. Praktische Anatomie, Bd 1, T. 4, S. 215, B. u. a., 1972.
B. A. Ivanov, Yu. M. Lopukhin; A. A. Travin (An.).