ARTHROGRYPOSIS MULTIPLEX CONGENITA - Current Concepts And Review Of The'Wooden Doll' Syndrome
Alaric J Aroojis*, Shreyash M Gajjar**
*Lecturer; **Registrar; Dept. of Paediatric Orthopaedics, Bai Jerbai Wadia Hospital for Children, Parel, Mumbai - 400 012.
Children suffering from multiple joint contractures and other limb deformities are frequently seen by practising orthopaedists and paediatricians. It behoves the orthopaedic surgeon to be aware of the nature and management of these complex deformities - collectively referred to as arthrogryposis multiplex congenita. The treatment of these children is multidisciplinary and is best carried out at paediatric institution equipped with a comprehensive care team comprising appropriate medical personnel. Management is prolonged, intensive and consists of physical therapy and stretching exercise combined with appropriate surgery at optimum time. Parental cooperation and compliance with therapy are prerequisites for a successful outcome.
Arthrogryposis multiplex congenita (AMC) is non-progressive congenital syndrome complex characterized by contracture of several joints in different parts of the body due to varying degrees of fibrosis of the affected muscles, thickening and shortening of periarticular capsular and ligamentous tissue with an intact sensory system and normal intellect.  This syndrome has been an enigma to the medical profession for decades and the congenital contractures and dislocations have been some of the most challenging and difficult deformities to manage.
Because of propensity for recurrence of deformity, William has referred to AMC as having an ‘evil reputation among orthopaedic surgeons. 
The term arthrogryposis (derived from two Greek words curved or hooked joint) is descriptive and not a diagnosis  and it is vital to recognize the heterogeneity of this condition. The first clinical description of the disorder was published by Otto in 1841. Although the term arthrogryposis multiplex congenita, coined by stern in 1923 continues to be the most widely accepted terminology, Swinyard has recently coined a more appropriate term-multiple congenital contractures.
AETIOLOGY AND CLASSIFICATION
Aetiology of AMC is undoubtedly multi-factorial. The deformities are known to occur as a component of a large group of heterogeneous neurogenic and myopathic disorders as well as of other disorders such as skeletal dysplasias.  In recent years, it has been accepted that within the context of heterogeneity, there are two main types : the neuropathic and the myopathic. Studies by Banker,  prove that the neuropathic form is seen in almost 90% of affected children compared to the myopathic type (< 10%).
The basic pathomechanism appears to be lack of foetal movement - foetal akinesia due to a congenital or acquired defect in the motor unit producing weakness early enough in foetal life to immobilize joints at various stages in their development. 
The clinical appearance of classical AMC is well recognized and the position of the limbs are typically symmetrical. Flexion or extension contractures or any combination of contractural deformity may occur in the limbs. In a study of 84 children by Hahn et al  , all 4 limbs were affected in approximately 70% of children, only lower limbs in about 20% and only upper limbs in < 10%. The frequency of joint involvement increases from distal to proximal but no synovial joints is exempt from contracture (Fig. 1).
Fig 1: Anthrogrypotic child with multiple joint deformities - 'wooden doll' syndrome.
The rigidity of joint is unique, in that there are always a few degrees of free and painless motion between the extremes of motion. The normal skin creases are usually absent and the skin is tense and glossy. Dimpling may be present at the joints and there may be definite webbing of the skin and subcutaneous tissues. On deep palpation subcutaneous tissue and muscle are found to be diminished in substance. The atrophy of the limbs combined with the cylindrical shape of the knees and elbows gives the patient a ‘Wooden doll’ appearance. There is no sensory deficit and the intellect is usually normal.
Fischer’s criteria for diagnosis of AMC (1970) :
- Joint contractures at birth in at least two different areas of the body (Patients with only bilateral clubfoot are excluded).
- Non-progressive neurological disorder.
- Muscle wasting with cylindrical limb configuration.
- Skin changes : featureless / loss of creases / presence of webbing.
Establishing an accurate diagnosis is the first and most important step in management and requires a complication of appropriate history physical examination and laboratory data. Detailed maternal and family history is mandatory. This is followed by a detailed physical examination especially the evaluation of neurologic status. All positive finding are carefully documented including the appearance of the involved extremities, the position of the joints and the passive range of motion. Appropriate investigative studies include serum enzyme measurements, EMG-NC studies and muscle biopsy.
PRINCIPLES OF MANAGEMENT
Management of AMC is complex and difficult but rewarding. Arthrogrypotic children are motivated. They will take advantage of gains that can be provided. It is surprising how they develop a functional degree of dexterity for performance of activities of daily living such as self-feeding, dressing and toilet needs.
The goals of treatment are maximum functional use of the upper limbs and independent or assisted ambulation.
COMPREHENSIVE CARE MANAGEMENT
The concept of comprehensive care is not new, but is growing in importance in centers specializing in paediatric musculoskeletal rehabilitation.2 Team members vary according to the diagnosis and the needs of the child. Each team member has specific skills and functions that are brought together to provide comprehensive care for the patient. The team at the authors institution which caters to a caseload of approximately 25 new patients per year comprises a paediatrician, an orthopaedic surgeon, a physical therapist, an occupational therapist, an orthotist and a social worker. A genetic evaluation and counselling are recommended when indicated.
The orthopaedic surgeon establishes and coordinates the individual rehabilitation plan which consists of organizing physical and occupational therapy programmes, planning appropriate surgery at the optimum time and orthotic implementation.
The social worker aids in obtaining community services for the affected families, arranges financial aid and assists in placement of affected individuals as useful members of the community.
The managing paediatrician functions as the coordinator of care. He typically provides for the child’s routine health needs, rules out associated congenital anomalies and serves as a professional liaison between hospital, school and community.
ORTHOPAEDIC MANAGEMENT OF AMC
In the arthrogrypotic child, the contracted joint capsule and rigid periarticular soft tissues do not stretch as the limb grows. Hence it is best to explain to the parents that because of the recalcitrant nature of the disease, the deformities will recur and require repeated corrections. The contracted soft tissues are so rigid that they do not yield to manipulative stretching and casting. In fact, such forceful measures may be detrimental as they cause cartilage necrosis, intra-articular adhesions, iatrogenic fractures or ankylosis. Early surgical release of the contracted soft tissues is the conservative method of deformity correction. It is crucial to perform daily physical therapy for a prolonged period to maintain the correction as well as to splint the limb with appropriate orthosis  (Fig. 2).
Fig 2: Anthrogrypotic child operated for bilateral TEV , right dislocation and left hip dislocation. Patient standing and walking in orthosis.
Foot and ankle : Talipes equinovarus and convex pes valgus which are the commonest deformities require open surgical correction at an early age by soft tissue or bony procedures. In newborns till 3-4 months of age, stretching exercises and plaster casts may be used but caution should be exercised not to produce iatrogenic deformities.
Knee : Flexion deformity, if mild can be adequately treated by stretching casts, night splinting and physical therapy. Moderate to severe flexion deformity require surgical release of the hamstring and posterior capsulotomy of the knee joint.
Hip : Unilateral hip dislocations are treated by soft tissue release followed by open reduction with femoral shortening. Bilaterally dislocated hips, especially if stiff, are best left alone. Hip deformities without dislocation are treated by a combination of physical therapy, splintage and appropriate surgical release.
Upper limb : In the upper limb, the commonly performed surgical procedure includes posterior elbow release, tendon transfers and wrist fusion. It is well recognized that arthrogrypotic children develop functional hand patterns for activities of daily living and dexterity is rarely an issue.
The birth of a child with musculoskeletal deformities a catastrophic event for new parents. Throughout pregnancy, parents indulge in a process of psychological preparation that focuses on the imagery associated with the expected child. The birth of a child with multiple deformities not only destroys that vision but also brings to the fore negative emotions such as guilt, anger, loss and grief. The attending physician should not only be able to deal with these negative attitudes but also must be able to solicit the parents’ full cooperation as amateur ‘stretchers’ and ‘splinters’ in the comprehensive team management of their affected children.
- Banker BQ. Neuropathologic aspects of arthrogryposis multiplex congenita. Clin Orthop 1985; 194 : 30.
- Hahn G. Arthrogryposis : Paediatric review and habilitative aspects. Clin Orthop 1958; 194 : 104.
- Hall JG. An approach to congenital contracture. Paediatr Annu 1981; 10 : 15.
- Palmer PM, Mac Ewen GD, Bowen JR, Mathew PA. Passive motion therapy for infants with arthrogryposis. Clin Orthop 1985; 194 : 54.2.
- Thompson GH, Bilenker RM. Comprehensive management of AMC. Clin Orthop. 1985; 194 : 6.
- Williams PF. The management of AMC. Orthop Clin North Am 1978; 9 : 67.