The clinical symptoms of knee extension and push patellar lateral shift over its width 1/2, 30. Push the patella out of the > 1CM is call
The clinical symptoms of knee extension and push patellar lateral shift over its width 1/2, 30. Push the patella out of the > 1CM is called patellar instability. The patella is the body's largest sesamoid, the main function is to transfer and strengthen the unit four quadriceps strength, maintain the stability of the knee, protect the femoral articular surface. The dynamic balance of the static balance and the stability of the patella femoral head four muscle on the patella, femoral condyle shape, around the joint capsule, ligament, patellar instability is one of the common diseases of the patella, is a common cause of chondromalacia of patella and osteoarthritis. Early detection of early treatment can avoid the occurrence of patella softening and osteoarthritis.
Neyret think there are four factors that lead to patellar instability: (1), femoral condyle dysplasia (trochlear dysplasia) (2), patella tilt (patellar tilt) (3) (tibial tubercle, tibial tubercle offset offset) (4), high (patellar height), the total of these four nodes at all because of the patellar ligament (Patellar tendon) which are too long.
Two, clinical diagnosis:
1, the symptoms of pain, weak legs (giving way), pseudo incarcerated (pesudolocking).
2, signs: femoral head muscle atrophy, knee joint swelling, (squinting knee), patellar tenderness or extrusion pain, joint laxity (laxity), Q angle. Unit four biceps pull axis and long axis angle of patella patellar ligament in the midpoint of the called Q angle. Clinical on the anterior superior iliac spine to the midpoint of the line of patella and tibial tubercle to the midpoint line of intersection angle of patella to represent in men. The normal 8 ~ 10, 10 ~ 20 normal women, when the shares of four head muscle dysfunction, or knee valgus, external rotation of the tibia, tibial tubercle and partial femoral anteversion deformity when Q angle increased, the femoral head four muscle contraction will make the lateral displacement of the patella.
3, radiation inspection and measurement.
I, X ray examination
X-ray examination including knee anteroposterior, lateral and axial patellofemoral joint radiographs.
(1) knee radiograph: patient supine, feet together, toes upward, the stock four muscles completely relaxed, AP piece.
(2) lateral radiographs
A, Insall and Salvati method (ratio method): mainly used to measure the location of patella height. 30. Bit position image. The measurement of patellar tendon length (Lt) from the pole of the patella to the tibial tubercle on the vertex edge, then measuring the patella the longest diagonal length (Lp) the ratio of two Lt/ Lp,
Its normal value is 0.8 ~ 1.2.
B, Blackburne-peel method: knee flexion 30. Lateral image. The vertical distance (A) of the patella to the tibial plateau was measured, and the length of the articular surface of the patella (B) was measured. The normal A/B ratio was 0.8. C, Labelle and Laurin: 90. The lateral image, along the leading edge of the cortex to the distal lead.
C, high measuring method of patella in children (midpoint): lateral X-ray point as to find out the bottom of the femoral epiphyseal line (F), the midpoint of the tibial epiphyseal line (T) and patellar axis diagonal point (P). 50 normal knees. -150. The ratio between PT and FT was 0.9-1.1.
(3) axis radiograph (patellofemoral cut a): most of patellar instability occurred less than 25 degrees in the knees, when the knee flexion > 25 degrees, on the patellofemoral joint X-ray will lost many important clinical data. On the contrary, the smaller the knee flexion angle, the more likely cases of patellar tendon abnormalities. Less than 25 of axial image diagnosis of patellar stability is of great significance, axial patellofemoral joint radiographs can show patella and trochlear dysplasia, displacement of patellofemoral joint discomfort and patella.
II, special radiography and other:
A, double contrast arthrography: injection of contrast agent and air into the joint cavity, can clearly display the meniscus and patellofemoral relative articular surface;
B, computed tomography (CT): micro CT scanning in flexion and knee extension position, can better reflect the development of femoral condyle, is particularly important for the flat patients, to provide a solid foundation for the next step to raise the surgical treatment of femoral condyle.
C, magnetic resonance imaging (MRI) examination: can be in the knee extension and micro flexion position scanning, measuring some parameters, such as the knee joint angle, etc.. Some of the symptoms is not obvious, but the general method is difficult to detect, such as instability of the patella subluxation can be found early and mild. For patients with patellar instability caused by trauma, it is recommended to perform MRI examination, and other injuries of the knee joint can be found, such as anterior cruciate ligament injury, posterior cruciate ligament injury, meniscus injury, and so on.
D, arthroscopy: Arthroscopy is not only helpful in diagnosis and differential diagnosis, but also a good treatment. The biggest advantage of arthroscopy is small trauma, quick recovery after operation, and at the same time, on the basis of arthroscopic examination, we can do the soft tissue operation of patella instability.
(a) conservative treatment: for patients with conservative treatment of patellar instability is not satisfactory, for mild illness, refused surgery or surgical contraindications, can limit the trial activities, unit four biceps function exercise, brace treatment and drug treatment.
(two) surgical treatment:
Patellar instability can be divided into 3 modes:
1, objective patellar instability, that is, the patient has symptoms of patellar instability, and at least a history of dislocation.
2, the potential instability of the patella, that is, patients with patellar pain and other symptoms, but no dislocation of the patella.
3, the patella pain syndrome, that is, the patient only patellar pain, no history of patellar dislocation and anatomical abnormalities. Surgical treatment can be divided into soft tissue surgery and bone surgery. The purpose of surgical treatment is to improve the power line of patella and to reconstruct the knee extension device.
1, soft tissue operation: soft tissue surgery for mild symptoms, without the occurrence of patellofemoral joint cartilage degeneration patients.
A, lateral lysis of patellar instability: when the symptom is lighter, do not need to do big surgery, alone the lateral soft tissue structure loose, loose main lateral supporting ligaments and lateral femoral muscle, this operation method to maintain the integrity of the synovial membrane.
B, lateral release medial reefing solution: in addition to the lateral and medial ligaments and joint capsule will fully open, the joint capsule incision suture overlap, this method is method for correcting patellar alignment is the most basic.
C, Campbell, with the medial patella support center bottom with the fascial flap from the femoral head four muscle attachment across the bottom lateral to the medial and then pulled out, turning and sutured to the medial condyle of the femur, and shorten suture with medial support.
D, Roux-Goldthwait: a longitudinal incision lateral patellar ligament, stripped from the tibial tubercle, pulled medially and sutured to the tibial tubercle.
Methods: e, Backer in the lateral patellar medial tightening on the basis of loose solution, the semitendinosus muscle from the point above the 10 - 15cm tendon cut off from inside out on the patella as tunnel, the distal head of the semitendinosus muscle from the distal patellar tendon through the tunnel, the tension, the tendon broken return back end to correct the crease edges of patella, patellar alignment, reduce the Q angle.
F, Galeazzi method: in the central part of the semitendinosus tendon, the distal end of the patella from the inside of the oblique pull out above, and then close to the medial part of the fixed.
G, Elmslie-Frillat method: medial support with suture. Suitable for children and preschool children.
2, bone surgery:
A, Hauser: patellar ligament insertion in the tibial tuberosity along with its attachment to the medial cortical bone and distal transitional, fixed. The epiphysis has closed, patients with patellar dislocation or subluxation or instability with satisfactory results.
B, tibial tubercle transfer and lateral neurolysis of tibial tubercle: inward rotation, without further transposition of tibial tubercle.
C and Maquet proposed: transposition of tibial tubercle of tibial tubercle advancement in treatment of patellofemoral disorders for more than 20 years, with satisfactory effect. Is the main method in the method, the tibial tubercle after implantation of bone block fast simple, elderly patients can also be performed, but should pay attention to move can not exceed 10mm, otherwise easy to cause local discomfort or nodules of bone necrosis.
D, patellar osteotomy: mainly to patellar malalignment due to patellar instability, and then those of chondromalacia of patella.
E, the external condyle of femur: the main adaptation angle is greater than 150. More patients.
F, osteotomy of the femur, and improvement of the tibial line of force: this procedure is applicable to the distal femoral line anomaly (varus or valgus). Surgical treatment of traumatic dislocation and no family history.
G, patellectomy unit four quadriceps plasty: recurrent patellar dislocation with severe patellofemoral joint deformation, considering the excision of patella, repair of femoral head four muscle structure.
Patellar instability is a common disease, the diagnosis depends on the symptoms, signs and auxiliary examination together, not subjective. A lot of methods in treatment, each has its advantages and disadvantages, to strictly grasp the indications and contraindications, the author suggests that, for different patients with patellar instability, can choose the combined application of one or more surgical methods according to different condition, will receive good treatment effect.