I. Pathogenesis.
Closed Achilles tendon injury, the ankle in the hyperextension position sudden force injury, rupture mostly occurs in the Achilles tendon stop point 2 ~ 6 cm above. This is closely related to the anatomical characteristics of the Achilles tendon.
1, the Achilles tendon is the strongest, fat tendon, about 15.0cm long, from the calf in 1/3, ending at the midpoint of the heel tuberosity. Achilles tendon from top to bottom gradually become narrower and thicker, in the heel node above 2 ~ 6cm for the narrowest. The stopping point is located under the skin, and there is a bursal liner in front and behind the Achilles tendon above the stopping point.
2, there is no tendon sheath around the Achilles tendon, only loose mesh tissue (peritendinous tissue), peritendinous tissue connects the tendon and its surrounding fascia. The blood vessels within the tendon supply nutrition to the Achilles tendon. There are 7-8 lubrication layers on the dorsal side of the Achilles tendon, each layer has its own nutrient vessels, and there are blood vessels passing between the layers; when the ankle joint moves, there can be activities between the layers.
3.The distribution of the nutrient arteries of the Achilles tendon shows that the lower segment area has relatively less blood supply. The number of vessels in the Achilles tendon gradually decreases with age. The blood supply to the Achilles tendon comes from two main arterial sources, namely the tibial artery source and the peroneal artery source. The tibial artery gives off deep and superficial branches of the medial Achilles tendon artery and deep longitudinal branches of the Achilles tendon artery. The former nourishes the Achilles tendon from the medial side and nourishes the medial Achilles tendon from top to bottom; the latter runs the entire length of the Achilles tendon and is the most important nourishing artery of the Achilles tendon. The peroneal artery divides into the external superior and inferior Achilles tendon arteries, which nourish the Achilles tendon from the lateral side. These arteries form an arterial network in the outer and inner membranes of the Achilles tendon. stein et al. also confirmed by radionuclide scanning that the segmental vessels in the 2-6 cm of the Achilles tendon stop were less visible.
Injury to the Achilles tendon causes local malnutrition and degeneration, which creates the conditions for Achilles tendon rupture. Long-term chronic strain on the Achilles tendon produces Achilles tendonitis and peritendinitis, and the Achilles tendon tissue becomes brittle, and peritendinitis affects the microcirculation of the Achilles tendon and affects the blood supply to the Achilles tendon. Some patients have scattered incomplete disconnection of tendon bundles before complete rupture, and when encountering sudden violence, the anatomical continuity of Achilles tendon is completely interrupted, that is, closed Achilles tendon rupture occurs.
II. Diagnosis.
1, clinical manifestations.
(1) There is a clear history of direct cutting or striking with sharp or blunt objects or after strenuous sports such as running and jumping.
(2) Swelling and pain in the Achilles tendon, weakness of plantarflexion of the foot, inability to stand and walk.
(3) Physical examination: interruption of the continuity of the Achilles tendon and depression can be palpated, toe flexion strength is significantly reduced, heel lift test is positive, Thopmson’s sign is positive.
(4) X-ray examination showed local soft tissue swelling, and MRI showed interruption of Achilles tendon continuity.
2.According to the patient’s history, symptoms, signs and imaging examination, the diagnosis of Achilles tendon rupture is generally not difficult, but it is easily overlooked by young doctors and missed. The reasons for the missed diagnosis are.
(1) Open injuries are only considered as soft tissue skin lacerations without detailed examination.
(2) The plantar flexion activity of the foot does not completely disappear after the rupture of the Achilles tendon, because the posterior tibial muscles, the long and short peroneal muscles, and the flexor toe muscles can still do the flexion of the ankle and toe.
(3) After the rupture of Achilles tendon, some patients can still stand and limp. Therefore, in clinical work, detailed medical history should be taken and careful physical examination should be conducted to avoid missing the diagnosis.
(3) Within 1 week after the injury, at most 10 days, the Achilles tendon fibers are seen to be bright white, tough, without edema or with a very light degree of edema, and the tissue has a good hold on the suture when suturing.
(1) 10~20 days after injury, the peritendinous tissue is swollen, the granulation scar is brittle, the Achilles tendon fiber tissue becomes brittle, the holding power of the suture is weak, and the firmness of the suture is reduced.
(2) After 20 days post-injury, the swelling of Achilles tendon fibers decreases, the scar slightly ages, the holding power of sutures increases, and the suture feels good.
So we suggest that the dividing line of Achilles tendon injury is set at 10 days after the injury for acute injury; 10~20 days for subacute injury; 20 days after for old injury.
Three, treatment.
1, Achilles tendon rupture is a common orthopedic trauma, partial rupture of Achilles tendon can basically heal by non-surgical treatment, while complete Achilles tendon mostly needs surgical repair. Non-surgical treatment is to fix the foot in plantar flexion position for 8~12 weeks.
In fresh Achilles tendon rupture, the rupture end is not flush and the proximal retraction defect is about 3 cm, end suture Bunnell method, end modified Kellssler suture plus fine silk interrupted tendon bundle suture can be used; while in Achilles tendon rupture more than 3 weeks, the proximal retraction defect is scar connection, the Achilles tendon is extended without tension, and the Achilles tendon shortening is often not end sutured. Abraham V-Y suture is indicated for subacute injury, not heavy degenerative necrosis at the severed end, and old ruptures with Achilles tendon shortening ≤6 cm; for old ruptures with Achilles tendon shortening ≥6 cm, Lindholm method, White Krynick method, Rugg and Bogoe method, flipped gastrocnemius tendon flap reinforcement method, simple metatarsal muscle reinforcement, use of peroneus longus muscle as well as artificial material repair, and broad fascia graft can be used.
There are V-Y shortening, flip 1~2 gastrocnemius tendon flap reinforcement suture, metatarsal tendon reinforcement, short peroneal tendon reinforcement, flexor digitorum longus tendon reinforcement, fascial strip reinforcement, combined muscle and tendon flap reinforcement of gastrocnemius, Dupont polyester sheet reinforcement, carbon fiber strip reinforcement, proteoglycan thread reinforcement, polyethylene mesh reinforcement, etc.
The patient is placed in prone position with local anesthesia or continuous epidural anesthesia. The medial incision of the Achilles tendon is made with a 10-15 cm long posterior medial incision, which is 1 cm away from the Achilles tendon, i.e., the incision is kept away from the center to prevent the shoe from rubbing the Achilles tendon causing local irritation symptoms. The skin incision is made directly to the skin, subcutaneous, and deep fascia, protecting the deep fascia from the subcutaneous tissue, that is, without subcutaneous tissue freeing, and protecting the peritendinous tissue to fully reveal the ruptured Achilles tendon. For fresh Achilles tendon rupture, we recommend end-to-end modified Kessler suture with fine silk interrupted tendon bundle suture. Old ruptures with Achilles tendon shortening ≤6 cm are repaired with Abraham V-Y sutures (old ruptures with Achilles tendon shortening ≥6 cm are repaired with Lindholm’s method, which can be reinforced with metatarsal tendon or peroneal long and short tendons.
Achilles tendon injuries due to traffic accident injuries are often accompanied by defects of the heel bone and skin, which are difficult to be successfully repaired by local skin release reduction sutures/free skin grafts, and are currently mostly repaired by.
(1) transposition of tendons with myotendinous tips to repair Achilles tendon defects.
(2) transposition of tissue flaps with vascular tissues to repair Achilles tendon defects.
(3) anastomotic composite tissue flap free graft for repair of Achilles tendon defects.
(4) Achilles tendon replacement for repair of Achilles tendon defects.
2. Ander-Lindhorm criteria for determining the efficacy: normal range of ankle movement: 20° dorsiflexion to 45° plantarflexion; slightly limited dorsiflexion: 10° dorsiflexion to 45° plantarflexion; no adhesion between Achilles tendon and skin.
3. Complications: including re-rupture, incision infection, adhesion of Achilles tendon, poor healing of incision, etc.
The occurrence of surgical complications is related to the rupture site, type and the degree of peritendinous soft tissue damage, and the correct surgical operation and standardized rehabilitation training can reduce their incidence.
(1) The Achilles tendon rupture should be operated before the swelling appears, otherwise it should be operated after the swelling subsides and the skin folds appear to avoid incision infection, skin necrosis and adhesions between the Achilles tendon and the skin.
(2) A medial longitudinal incision of the Achilles tendon can avoid the posterior calf skin nerve injury brought about by the lateral incision and reduce the higher rate of skin necrosis and incision infection with a straight incision directly posteriorly.
(3) A sharp incision should be made to the deep fascia (extra tendon membrane) to avoid destruction of the subcutaneous nutrient vascular network and fat liquefaction caused by blunt stripping, thus reducing skin necrosis, infection and and adhesions in the incision, protecting the peritendinous tissue and avoiding destruction of its vascular bundle entering the Achilles tendon from the ventral side.
(4) The repaired Achilles tendon should have sufficient strength and not be under excessive tension to avoid blocking the blood supply to the severed end and affecting healing.
(5) Locking edge suture makes the node buried in the severed end, and interrupted suture of the tendon outer membrane makes the node located in the subcutaneous tissue, which can reduce the node irritation.
(6) Postoperative plaster support is fixed in the flexed knee and plantarflexed position to reduce tension at the anastomosis.
IV. Hormone application
The spontaneous rupture of the Achilles tendon should be taken seriously after the local application of hormones, which leads to inflammatory damage to the small blood vessels around the Achilles tendon, increases vascular permeability, triggers intravascular coagulation, affects blood flow around the Achilles tendon, causes degenerative lesions of the Achilles tendon, increases brittleness, decreases elasticity, and reduces the load it can bear. Therefore, after the local application of hormones, the tendon load is impaired and it is easy to rupture the Achilles tendon; for peri-Angel tendon inflammation, the problems that can be solved by general physical therapy should be avoided as much as possible by dipping into the new sex therapy (local closure), even if the painful points are closed, the indications and the concentration of drugs should be strictly controlled, and weight-bearing activities should be avoided after treatment. Special care should be taken in its surgical treatment, otherwise it is easy to have skin incision problems, exposed Achilles tendon, prolonged hospital stay and increased treatment cost.