Congenital polyarticular contracture is a syndrome characterized by stiffness of multiple joints throughout the body due to fibrosis of muscles, joint capsules and ligaments.
Clinical manifestations
The clinical manifestations of the disease are complex, and Hall divides the disease into three major categories according to the extent of the lesions involved.
The first category involves only the joints of the extremities, accounting for about 50% of the cases; it can be divided into two subtypes: muscular dysplasia and distal limb joint contracture. The former is a typical joint contracture. Usually, symmetrical joint stiffness of the extremities can be found after birth, mostly in the flexion position, but also in the extension position, but most of the last few degrees of flexion or extension activities are retained. There is significant muscle atrophy in the affected limbs and cylindrical changes in the knee and elbow joints. The patient has a puppet-like appearance due to loss of normal skin texture and shiny and tense skin. When the joint is contracted in the flexed position, the skin and subcutaneous tissue may form a web-like deformity. Skin sensation is normal, but deep tendon reflexes are often diminished or absent. Although all four extremities can be involved, 46% of all four extremities are involved, 43% of both lower extremities are involved, and 11% of upper extremities alone are involved. When the lower extremity is involved, the foot is often plantar flexion and valgus deformity, knee flexion or extension, hip flexion and external rotation, abduction, or hip flexion and internal contraction with dislocation. In addition, 20% of patients have late onset C-shaped scoliosis. Upper extremity deformities include internal rotation of the shoulder joint, flexion or extension of the elbow joint, radial head dislocation, forearm rotation and wrist flexion contracture, and thumb inversion and flexion close to the palm with proximal interphalangeal joint flexion contracture. In the distal limb contracture type, only the hand and foot are involved, in which the thumb is flexed and inward across the palm of the hand, and the other four fingers are flexed in a fist-like manner, with fingers overlapping each other. The foot deformity refers to plantar flexion inversion, but it can also be a heel exostosis with toe flexion contracture.
The second category is joint contracture with visceral, head and facial deformities. In addition to joint contracture, there are other deformities such as Marfan syndrome, Freemam-Sheldon syndrome and pterygium syndrome.
The third category is joint contracture with neurological anomalies. Joint contracture with severe neurological anomalies, such as triploidy 18, 9, 8, cerebral malformations, and cerebrospinal bulge, are usually autosomal anomalies and can be diagnosed by peripheral blood karyotyping, but the infant usually dies at an early age.
Differential diagnosis
The diagnosis is easily made with typical physical signs, such as muscle atrophy of the limbs, symmetrical contracture of the joints, and normal skin sensation. However, in the distal limb contracture type, the hand and foot deformities tend to worsen slowly, especially in those with late presentation, and need to be differentiated from rheumatoid arthritis and congenital bone and joint deformities. However, the deformities of hands and feet in this type of patients are mostly symmetrical in distribution, which is a characteristic of this disease. Secondly, there are often no abnormal findings in laboratory tests.
When the lower extremity is involved, the foot is often plantar flexion and valgus deformity, knee flexion or extension, hip flexion and external rotation, abduction, or hip flexion and internal contraction with dislocation. In addition, 20% of patients have late onset C-shaped scoliosis. Upper extremity deformities include internal rotation of the shoulder joint, flexion or extension of the elbow joint, and radial head deformity.
Treatment of this disease faces many difficulties and requires multiple surgeries because of the many joints involved. The recurrence rate after surgery is high and repeated surgeries are required. However, the IQ of the affected children is mostly higher than that of ordinary children, and after effective treatment, they can acquire amazing self-care ability. Therefore, physicians and parents should have confidence. The goal of treatment is to increase the range of motion of the affected joints so that the child can walk independently or with assistance and improve the ability to operate the upper limbs and hands to the greatest extent possible, therefore, treatment should follow the following principles.
1. Early soft tissue release, incision or removal of certain joint capsules, ligaments and contracted muscles that hinder joint movement can enable the affected joint to obtain a certain range of motion. As the contracted soft tissues are hard and tough, physical therapy such as passive pulling and massage will not only be ineffective, but also cause necrosis of the articular cartilage due to increased pressure.
2, although pure physical therapy has no corrective effect, but on the basis of soft tissue release, adhere to physical therapy, can maintain the effect of surgical release, postpone the interval of recurrence.
3, the brace fixation has a certain auxiliary role, night wear is conducive to maintain the position of surgical correction, day wear can assist walking.
4.Since the disease has the tendency of recurrence after surgery, the application of muscle a tendon displacement, replacing certain muscles that have been fibrotic or weak, can obtain muscle balance, thus improving the function of the limb. However, the results are worse than those of similar surgery for poliomyelitis.
Guided by these principles, the surgical approach should be selected for each patient based on the specific nature of the deformity, the degree of deformity, and the age of the patient. Clubfoot and supinated clubfoot are common foot deformities in this disease and require early surgical treatment. Usually children can be treated surgically at 3 months of age, and preoperatively they are fixed with a cast to stretch the tense skin. The contracted joint capsule and ligaments should be removed during surgery. For clubfoot deformity, complete release around the talus and central repositioning of the heel and talonavicular joint should be achieved. If the lateral column of the foot interferes with the repositioning, the anterolateral part of the heel bone can be removed (Lichtblau procedure) or the heel dice joint can be removed (Evans procedure). After surgery, the foot can be heel-plantar weight-bearing although stiffness can be obtained. If difficulty is encountered in the treatment of supination exostosis, the navicular bone can be removed, which can easily form a ball and socket joint between the talus and the 1st to 3rd cuneiform bone, and also prevent ischemic necrosis of the talus. Knee flexion contracture is more common, and mild flexion (<20°) does not affect function. It can be fixed with a night brace to prevent aggravation with age. Moderate flexion deformity (20° to 60°) should be treated with early surgery, mainly by incising the posterior joint capsule while lengthening the cord muscle. If contracture of the lateral collateral ligament and anterior cruciate ligament prevents knee extension, these ligaments can be lengthened in young children. In older children, a supracondylar posterior osteotomy should be performed. If the knee deformity exceeds 60°, soft tissue release is likely to cause sciatic nerve and arteriovenous injury requiring a bone shortening and posterior revision osteotomy. Another option is anterolateral epiphyseal lagging of the distal femur and proximal tibia, but the results are not satisfactory. Knee extension deformities are less common and can be fixed by manual distraction and bracing in the neonatal period. If the infant has reached 6 months of age and the deformity has not been corrected by manual retraction, quadriceps plication can be chosen to obtain a more satisfactory result, and long-term fixation with a postoperative night brace can reduce the recurrence rate. Hip deformity is complicated and can be divided into: hip deformity with dislocation and. Hip deformity without dislocation. Hip dislocation can be unilateral or bilateral.
If both hips are dislocated and have joint stiffness, treatment is not recommended. This is because surgical treatment is likely to produce non-dislocated or semi-dislocated stiffness in both hips, which is worse than double hip dislocation with stiffness. In the case of single hip dislocation with stiffness, a combination of thorough soft tissue release, incision and repositioning and femoral shortening osteotomy can improve the function of the hip joint. If both hips are dislocated without stiffness, they should be surgically released and resected. The hip should be fixed with an abduction brace for 3 to 6 months after surgery.
Those without dislocation of the hip joint may have the following deformities.
1.Abduction, external rotation and flexion deformity
2.Simple abduction deformity
3.Simple extension deformity
4.Simple flexion deformity
Among them, hip abduction, external rotation and flexion deformity are the most common, and unilateral cases are often prone to scoliosis, and bilateral cases have awkward gait, which can be taken to release the hip bundle tibia, cut or lengthen the broad fascia tensor and iliopsoas muscle. Abduction deformity is rare, and surgery is performed to release the gluteus medius and minimus muscles and the gluteus fascia. Simple hip flexion deformity is more common, but often not serious, and can be corrected by choosing brace treatment or prone sleep, while serious cases need surgical release of hip flexor muscle groups. Hip extension deformity alone is very rare and can be treated by surgical release of the gluteus maximus, posterior fascia and ligaments.
Upper extremity joint contractures are common in elbow, wrist and finger deformities. In elbow flexion contracture, the biceps and brachioradialis tend to retain some function, but the triceps is weak, and its flexor capsule and ligaments are thickened and contracted. In mild cases, passive tension and plaster immobilization in elbow extension are used, and orthopedic effects are maintained at night with brace immobilization. In more severe cases of elbow flexion contracture, surgical release and lengthening of the biceps and brachialis muscles should be performed, and postoperative brace fixation is still required to prevent recurrence. Elbow extension contracture is more complicated, often combined with forearm rotation, wrist flexion and finger deformity. The triceps brachii muscle is stronger, while the biceps brachii muscle is weakened or completely absent. Passive pulling and plaster orthosis not only cannot correct the elbow extension deformity, but also may cause articular cartilage necrosis and intra-articular adhesions, which may aggravate the elbow stiffness. Because elbow extension deformity has a great impact on the function of the upper extremity of the child, such as eating, urination and defecation and other daily activities, surgery is required.
The surgical approach includes triceps tendon lengthening, release of the posterior joint capsule and ligaments of the elbow joint, and transposition of the triceps and pectoralis major muscles to reestablish elbow flexion. Triceps tendon lengthening and release of the posterior elbow capsule and ligaments can significantly increase elbow flexion activity. However, due to the weakness of the flexor elbow muscles, it is easy to recur after surgery. Therefore, after the patient is 5 years old and able to cooperate with functional training, the triceps and pectoralis major muscles should be selected for transposition and reconstruction of flexion of the elbow. In some cases, if the patient needs to walk with crutches or in a wheelchair, the elbow joint extension position is more favorable to complete the above mentioned movements. Therefore, if both elbows have elbow extension deformity and need to walk with crutches or in a wheelchair, only one elbow can be reconstructed in flexion.
Wrist flexion contracture is not only common but also severe (up to 90°) with ulnar deformity. Correction of this deformity can significantly improve the function of the upper extremity, so the sooner the better, and some even advocate the passive pulling and plaster brace fixation of infants a few days after birth, and the simultaneous correction of thumb and other finger deformities. If the wrist flexion contracture is more fixed, a series of plaster cast orthosis is needed and good results will be received. However, if the wrist extensor muscle strength is weakened, it is easy to recur. The ulnar wrist flexor can be selected for displacement at an early stage to reconstruct the wrist extension function. Williams advocates internal fixation with intramedullary nail to keep the wrist joint stable after 6 years of age, fixing the wrist palmar flexion at 5° with intramedullary nail on the third metacarpal and distal radius, and keeping the intramedullary nail until the skeletal development is mature, and fixing it with plaster after wedge resection of the wrist joint to make it fused. Tachdjian, on the other hand, takes a dorsal wedge osteotomy of the distal radius and ulna to treat severe wrist flexion stiffness, which can both correct the deformity and relatively lengthen the muscles and soft tissues on the flexed side of the wrist. In the case of anterior rotator contracture of the forearm, selection of anterior rotator round muscle cut, or displacement of anterior rotator round muscle to replace the function of the posterior rotator muscle can be satisfactorily corrected. The thumb inversion flexion deformity often has thumb long extensor, thumb short muscle and abductor muscle dysplasia or deficiency, resulting in contracture of the thumb collector muscle, soft tissue of the tiger’s mouth, common finger and interphalangeal joint, which seriously hinders the function of the thumb to palm and grasp. Passive pulling and brace fixation can be applied in infancy. In early childhood, thumb function can be improved by applying tiger plication, cutting off the beginning of the thumb retractors and lengthening or tendon displacement of the long thumb extensors. Although finger flexion contractures are common, they are not serious and can be prevented from worsening with age by passive pulling and nighttime brace fixation. In severe cases, the superficial finger flexors and lateral collateral ligaments need to be released and immobilized with a fine kerf pin for three weeks. If the dorsal extension of the finger improves with frequent lateral releases, but wrist flexion deformity develops, a segmental incision should be made in the forearm to extend the muscle and tendon migration of the deep and superficial finger flexors. Postoperative immobilization with a cast or brace, especially long-term nocturnal brace immobilization may prevent recurrence or prolong the interval between recurrences. Dislocation, forearm rotation and flexion contracture of the wrist joint, and thumb inversion and flexion close to the palm with flexion contracture of the proximal interphalangeal joint.