Arthrogryposis multiplex congenita: dental and maxillofacial phenotype - A scoping review.

INTRODUCTION: Arthrogryposis multiplex congenita (AMC) is a heterogeneous group of disorders associated with decreased fetal movement, with a prevalence between 1/3000 and 1/5200 live births. Typical features of AMC include multiple joint contractures present at birth, and can affect all joints of the body, from the jaw, and involving the upper limbs, lower limbs and spine. The jaws may be affected in 25 % of individuals with AMC, with limited jaw movement and mouth opening. Other oral and maxillofacial deformities may be present in AMC, including cleft palate, micrognathia, periodontitis and delayed teething. To our knowledge, oral and maxillofacial abnormalities have not been systematically assessed in individuals with AMC. Therefore, this scoping review was conducted to identify, collect, and describe a comprehensive map of the existing knowledge on dental and maxillofacial involvement in individuals with AMC. METHODOLOGY: A scoping review was conducted in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews guidelines. The PRISMA guidelines for scoping reviews were followed and databases were searched for empirical articles in English and French published until October 2022. We searched MEDLINE, Embase, Web of Science and ERIC databases. Two authors independently reviewed the articles and extracted the data. RESULTS: Of a total of 997 studies that were identified, 96 met the inclusion criteria and were subsequently included in this scoping review. These 96 studies collectively provided insights into 167 patients who exhibited some form of oral and/or maxillofacial involvement. Notably, 25 % of these patients were within the age range of 0-6 months. It is worth highlighting that only 22 out of the 96 studies (22.9 %), had the primary objective of evaluating dental and/or maxillofacial deformities. Among the patients studied, a prevalent pattern emerged, revealing that severe anomalies such as micrognathia (56 %), high-arched palate (29 %), cleft palate (40 %), limited mouth opening (31 %), and dental anomalies (28 %) were frequently observed. Importantly, many of these patients were found to have more than one of these anomalies. Even though these maxillofacial impairments are known to be associated with dental problems (e.g., cleft palate is associated with oligodontia, hypodontia, and malocclusion), their secondary effects on the dental phenotype were not reported in the studies. CONCLUSION: Our findings have uncovered a notable deficiency in existing literature concerning dental and maxillofacial manifestations in AMC. This underscores the need for interdisciplinary collaboration and the undertaking of extensive prospective cohort studies focused on AMC. These studies should assess the oral and maxillofacial abnormalities that can impact daily functioning and overall quality of life.

The emerging spectrum of fetal acetylcholine receptor antibody-related disorders (FARAD).

In utero exposure to maternal antibodies targeting the fetal acetylcholine receptor isoform (fAChR) can impair fetal movement, leading to arthrogryposis multiplex congenita (AMC). Fetal AChR antibodies have also been implicated in apparently rare, milder myopathic presentations termed fetal acetylcholine receptor inactivation syndrome (FARIS). The full spectrum associated with fAChR antibodies is still poorly understood. Moreover, since some mothers have no myasthenic symptoms, the condition is likely underreported, resulting in failure to implement effective preventive strategies. Here we report clinical and immunological data from a multicentre cohort (n = 46 cases) associated with maternal fAChR antibodies, including 29 novel and 17 previously reported with novel follow-up data. Remarkably, in 50% of mothers there was no previously established myasthenia gravis (MG) diagnosis. All mothers (n = 30) had AChR antibodies and, when tested, binding to fAChR was often much greater than that to the adult AChR isoform. Offspring death occurred in 11/46 (23.9%) cases, mainly antenatally due to termination of pregnancy prompted by severe AMC (7/46, 15.2%), or during early infancy, mainly from respiratory failure (4/46, 8.7%). Weakness, contractures, bulbar and respiratory involvement were prominent early in life, but improved gradually over time. Facial (25/34; 73.5%) and variable peripheral weakness (14/32; 43.8%), velopharyngeal insufficiency (18/24; 75%) and feeding difficulties (16/36; 44.4%) were the most common sequelae in long-term survivors. Other unexpected features included hearing loss (12/32; 37.5%), diaphragmatic paresis (5/35; 14.3%), CNS involvement (7/40; 17.5%) and pyloric stenosis (3/37; 8.1%). Oral salbutamol used empirically in 16/37 (43.2%) offspring resulted in symptom improvement in 13/16 (81.3%). Combining our series with all previously published cases, we identified 21/85 mothers treated with variable combinations of immunotherapies (corticosteroids/intravenous immunoglobulin/plasmapheresis) during pregnancy either for maternal MG symptom control (12/21 cases) or for fetal protection (9/21 cases). Compared to untreated pregnancies (64/85), maternal treatment resulted in a significant reduction in offspring deaths (P < 0.05) and other complications, with treatment approaches involving intravenous immunoglobulin/ plasmapheresis administered early in pregnancy most effective. We conclude that presentations due to in utero exposure to maternal (fetal) AChR antibodies are more common than currently recognized and may mimic a wide range of neuromuscular disorders. Considering the wide clinical spectrum and likely diversity of underlying mechanisms, we propose 'fetal acetylcholine receptor antibody-related disorders' (FARAD) as the most accurate term for these presentations. FARAD is vitally important to recognize, to institute appropriate management strategies for affected offspring and to improve outcomes in future pregnancies. Oral salbutamol is a symptomatic treatment option in survivors.

Similar Cognitive Skill Impairment in Children with Upper Limb Motor Disorders Due to Arthrogryposis Multiplex Congenita and Obstetrical Brachial Plexus Palsy.

Arthrogryposis multiplex congenita (AMC) and obstetrical brachial plexus palsy (OBPP) are motor disorders with similar symptoms (contractures and the disturbance of upper limb function). Both conditions present as flaccid paresis but differ from each other in the pathogenesis: AMC is a congenital condition, while OBPP results from trauma during childbirth. Despite this difference, these diseases are identical in terms of their manifestations and treatment programmes. We compared the cognitive skills of children with AMC and OBPP diagnoses with those of healthy children; we also compared the motor skills of impaired children with those of healthy ones. The patients in both groups significantly differed from the healthy children with regard to psychological parameters, such as 'visual memory capacity' and 'thinking'. Moreover, the two groups with children with AMC and OBPP significantly differed from each other in motor skill parameters, such as 'delayed motor development', 'general motor development', and the 'level of paresis'. Upper limb motor function in the OBPP children was less impaired compared to that of the AMC children. However, we did not find any significant differences in cognitive deficits between the AMC children and the OBPP children. This may indicate that motor impairment is more significant than the underlying cause for the development of cognitive impairment; however, the factors causing this phenomenon require further study (e.g., social environment, treatment, and rehabilitation programme).

An Unusual Combination of Arthrogryposis, Gastroschisis, Cecal Volvulus, and Malignant Hyperthermia in a Young Woman: A Case Report.

BACKGROUND The purpose of this study is to discuss a patient with a history of conditions, including arthrogryposis, gastroschisis, and malignant hyperthermia, who presented with cecal volvulus requiring urgent surgical intervention. CASE REPORT A 29-year-old woman with a history of arthrogryposis, gastroschisis, malignant hyperthermia, and multiple childhood abdominal surgeries presents to the Emergency Department (ED) with 2 days of abdominal pain and bloody diarrhea. A CT abdomen/pelvis revealed findings concerning for a cecal volvulus. The patient was premedicated and monitored closely by the anesthesia team due to her history of malignant hyperthermia. She underwent an exploratory laparotomy, where a dilated cecum and proximal ascending colon were found to be completely volvulized around the mesentery. Manual bowel detorsion was performed, which resulted in reperfusion of the ischemic-appearing bowel, which then appeared viable. She recovered well after the procedure and was discharged on postoperative day 5. CONCLUSIONS This case highlights a patient who presented with a combination of 4 findings: arthrogryposis, gastroschisis, malignant hyperthermia, and cecal volvulus. With arthrogryposis reported to be associated with gastroschisis and malignant hyperthermia, this report not only corroborates this association, but also aims to draw attention to the fact that these conditions have potential to occur jointly with cecal volvulus. Given the patient's history of gastroschisis requiring extensive abdominal surgeries that contribute as risk factors for cecal volvulus, it is possible there may be other arthrogryposis patients who present with cecal volvulus similar to that seen in this patient.

Skeletal anomaly and opisthotonus in early-onset epileptic encephalopathy with KCNQ2 abnormality.

BACKGROUND: Heterozygous KCNQ2 variants cause benign familial neonatal seizures and early-onset epileptic encephalopathy in an autosomal dominant manner; the latter is called KCNQ2 encephalopathy. No case of KCNQ2 encephalopathy with arthrogryposis multiplex congenita has been reported. Furthermore, early-onset scoliosis and opisthotonus have not been documented as characteristics of KCNQ2 encephalopathy. CASE REPORT: A male infant born with scoliosis and arthrogryposis multiplex congenita developed intractable epilepsy on the second day of life. At 4 months of age, he developed opisthotonus. The opisthotonus was refractory to medication in the beginning, and it spontaneously disappeared at 8 months of age. Whole-exome sequencing revealed a novel de novo heterozygous variant in KCNQ2, NM_172107.4:c.839A > C, p.(Tyr280Ser). CONCLUSIONS: Early-onset scoliosis, arthrogryposis multiplex congenita, and opisthotonus may be related to KCNQ2 encephalopathy.

The Effectiveness of Serial Casting in the Treatment of Recurrent Equinovarus in Children With Arthrogryposis.

BACKGROUND: Arthrogryposis multiplex congenita (AMC) is characterized by joint contractures in 2 or more body areas, often resulting in clubfoot deformities that are typically stiffer than those seen in idiopathic clubfoot deformities. While surgery is routinely used to treat clubfoot in AMC, it has a high rate of recurrence and complications. Current literature suggests serial casting (SC) could be useful in treating clubfoot in AMC, though evidence of its effectiveness is limited. METHODS: Passive range of motion (PROM), dynamic foot pressure, parent-reported Pediatric Outcomes Data Collection Instrument, brace tolerance, and the need for post-casting surgery were evaluated retrospectively in children with AMC treated with SC to address clubfoot deformities. Analysis of variance or paired t tests were used as appropriate on pre-casting, short-term (within 6 mo after SC) and/or longer-term (6 to 18 mo after SC) parameters to determine the effectiveness of SC. Brace tolerance before and after SC was analyzed using the Global Test for Symmetry, and medical records were reviewed to determine the need for surgery post-SC. RESULTS: Forty-six children (6.1±3.1 y old) were cast an average of 2.5±1.9 times, resulting in 206 SC episodes. PROM showed improvement in ankle dorsiflexion and forefoot abduction in the short term (P<0.05), returning to baseline measurements in the long term (P=0.09). Brace tolerance improved after casting (P<0.05). Only 15% of feet required surgery at follow-up at 10.3±5.5 years. There were no significant changes in dynamic foot pressure or Pediatric Outcomes Data Collection Instrument results after SC, except for an increase in the pain subtest (P<0.05). CONCLUSIONS: Serial casting in children with AMC can be effective in temporarily improving PROM and improving brace tolerance, but it does not impact dynamic barefoot position. Positive impact of conservative management in children with AMC can potentially delay or reduce the need for invasive surgical intervention by improving PROM and brace tolerance. LEVEL OF EVIDENCE: Level III, Retrospective Comparative Study.

Electromyography in Congenital Zika Syndrome.

INTRODUCTION: Congenital Zika virus syndrome is a distinct pattern of birth defects in fetuses infected by the Zika virus. It presents a broad clinical spectrum that includes occurrences of microcephaly, hypertonia, dysphagia, hyperexcitability, seizures, and arthrogryposis. Imaging findings show neuronal migration disorders. METHODOLOGY: Case reports have suggested that arthrogryposis has a neurogenic cause. We analyzed needle electromyography and nerve conduction examinations on 77 patients aged 2-24 months presenting highly probable congenital Zika virus syndrome, with or without arthrogryposis. RESULTS: All those with arthrogryposis presented with chronic muscle denervation in the electromyography examination. Similarly, children with single or reversible joint abnormalities at birth showed the same findings. Denervation in the paravertebral musculature was found in all of the children with diaphragmatic paralysis or thoracic deformities. CONCLUSIONS: We propose that congenital contractures associated with congenital Zika virus syndrome are caused by the malformation of upper and lower motor neurons during embryogenesis.

Expanding the phenotype of Bruck syndrome: Severe limb deformity, arthrogryposis, congenital cardiac disease and pulmonary hemorrhage.

Bruck syndrome is a rare collagen disorder with autosomal recessive inheritance caused by pathogenic variants in either FKBP10 or PLOD2 genes. It is characterized by bone fragility and fractures similar in severity and variability to osteogenesis-imperfecta as well as congenital joint contractures. This article describes an infant with a homozygous (partial) gene deletion of PLOD2 that includes the start codon and would be expected to lead to nonfunctional protein product. The infant had a severe phenotype of Bruck syndrome and is the only reported case of Bruck syndrome with congenital cardiac disease (triscuspid valve dysplasia with severe regurgitation, mitral valve prolapses with moderate regurgitation, and pulmonary hypertension) and pulmonary hemorrhage. We hypothesize that the additional feature of congenital cardiac disease in this case was due to the underlying defect in type I collagen, and that the pulmonary hemorrhage was multifactorial, with underlying vessel fragility, rib fractures, and high pulmonary pressures likely to be major contributing factors. Management was largely supportive with the use of bisphosphonates to assist in pain management. Care was complicated by comorbid cardiopulmonary compromise, limited evidence-base guiding care, and difficulties in discussing end-of-life care.

Fatal Retroperitoneal Bleeding in Neurofibromatosis Type 1: A Clinically Occult Complication.

ABSTRACT: Neurofibromatosis type 1 (NF1) is a common, autosomal dominant neurocutaneous syndrome. The most frequent clinical manifestations include multiple neurofibromas, café-au-lait spots, dystrophic scoliosis, benign and malignant peripheral nerve sheath tumors, and paragangliomas. Neurofibromatosis type 1 vasculopathy is a less well-recognized constellation of vascular pathologies that can cause significant medical complications in patients with NF1. A rare manifestation of this process is neurofibroma infiltration of vasculature with resultant bleeding. The case presented herein illustrates a rare example of a massive fatal hemorrhage due to disruption of a large paraspinal artery in the setting of a diffuse, infiltrative neurofibroma. This case highlights the potential of benign neurofibromas to infiltrate major blood vessels, leading to extensive bleeding and death.

Ichthyosis, petechiae, and arthrogryposis in a neonate.

Gaucher disease is a rare lysosomal storage disorder caused by a deficiency in glucocerebrosidase. This enzyme deficiency leads to the accumulation of toxic metabolites in various organs. Multiple subtypes of this disease have been described; however, the perinatal-lethal form is extremely rare and challenging to diagnose. We present a case of a newborn girl with ichthyosis, petechiae, and arthrogryposis, later found to be homozygous for a pathogenic variant of the glucocerebrosidase gene. This case highlights the potential role of dermatologists in the recognition of this rare disease.

Bruck Syndrome: Beyond the Obvious.

INTRODUCTION: Bruck syndrome is a rare autosomal recessive disease characterized by multiple joint contractures, bone fragility, and fractures. Two genes have been associated with Bruck syndrome, FKBP10 and PLOD2, though they are phenotypically indistinguishable. CASE PRESENTATION: We present a prenatally diagnosed case of Bruck syndrome in a young multiparous woman, with no notable personal, family or obstetric history. A 12-week ultrasound raised the suspicion of short long bones, subsequently confirmed at 16 weeks. In addition, bilateral fixed flexion of the elbow, wrist, and knee joints as well as talipes was observed. Chromosomal SNP microarray analysis (0.2 Mb) detected a homozygous deletion at chromosome 3, band q24, involving a part of PLOD2 to a part of PLSCR4. At mid-trimester morphology, bilateral intrauterine fractures of the humerus and femur were evident. In the late third trimester, a fetal echocardiogram noted enlargement of the right heart with severe tricuspid regurgitation in combination with pulmonary insufficiency and a restrictive arterial duct. The potential risk of premature closure of the ductus arteriosus near term led to delivery by emergency caesarean section. CONCLUSION: To our knowledge, this is the first case of Bruck syndrome prenatally confirmed by chromosomal microarray analysis and the second reported case with an extra-skeletal abnormality. This case highlights the importance of comprehensive fetal morphological assessment during pregnancy as diagnosis of an additional abnormality has the potential to impact both management and prognosis.

Open Reduction at 15 Months of Left Hip Dislocation in a Male Infant Diagnosed with Arthrogryposis.

BACKGROUND Arthrogryposis is a congenital condition of multiple contractures of joints associated with hip dislocation. The outcome of open reduction of hip dislocation in arthrogryposis patients is debatable. Open reduction of arthrogryposis is challenging for shallow acetabulum and extensive adhesions and fibrosis. For this reason, a careful extensive release must be carried out to achieve the open reduction of the hip in arthrogryposis patients. The literature lacks surgical recommendations for open reduction of the hip in arthrogryposis patients and how to deal with cases of the extruded bone segment during open reduction. CASE REPORT The patient presented in the first few weeks of life with bilateral clubfoot and left hip dislocation. Clinical diagnosis of arthrogryposis was made after referral to a genetics specialist. The hip was clinically irreducible. The patient underwent open reduction and femoral shortening using the Smith Peterson approach at the age of 15 months, with accidental extrusion of the proximal femur, which was retained immediately. The clinical outcome showed a painless, good range of motion. Radiographically, features of avascular necrosis and healed osteotomy site were evident. CONCLUSIONS A difficult hip reduction was expected in this arthrogryposis patient, which required careful dissection of surrounding fibrosis and appropriate femoral shortening. Careful dissection should be carried out during open reduction to avoid jeopardization of femoral head vascularity or even complete devitalization of the proximal femur.

Arthrogryposis multiplex congenita in a child with congenital fractures: a case report.

BACKGROUND: Bruck syndrome is an exceedingly rare form of osteogenesis imperfecta, inherited autosomal recessively and presenting with the concurrence of bone fragility and congenital contractures of large joints. The disease usually progresses relentlessly to result in recurrent fractures, short stature, severe kyphoscoliosis, and susceptibility to recurrent respiratory tract infections. CASE PRESENTATION: The index child was a male newborn to healthy, nonconsanguineous, Sinhalese parents. The child had multiple contractures involving all large joints with pterigium formation in addition to congenital fractures involving left humerus and ulna at birth. The phenotypic features in this child were highly suggestive of Bruck syndrome. Genetic counseling was offered to the parents, although specific genetic testing could not be undertaken due to lack of resources. Bone and skin biopsy were not performed since only palliative care was possible. Over the course, he developed recurrent severe chest infections due to poor muscle tone, weak cough reflex, and pooling of secretions. Unfortunately, he succumbed at the age of 7 months following severe pneumonia. CONCLUSION: The association of arthrogryposis with osteogenesis imperfecta is extremely rare and known as Bruck syndrome. Early diagnosis during the antenatal period is helpful in genetic counseling, assessment of severity, and exploration of therapeutic options.

Identification of UBA1 as the causative gene of an X-linked non-Kennedy spinal-bulbar muscular atrophy.

BACKGROUND AND PURPOSE: Spinal-bulbar muscular atrophy (SBMA) (Kennedy's disease) is a motor neuron disease. Kennedy's disease is nearly exclusively caused by mutations in the androgen receptor encoding gene (AR). The results of studies aimed at identification of the genetic cause of a disease that best approximates SBMA in a pedigree (four patients) without mutations in AR are reported. METHODS: Clinical investigations included thorough neurological and non-neurological examinations and testing. Genetic analysis was performed by exome sequencing using standard protocols. UBA1 mutations were modeled on the crystal structure of UBA1. RESULTS: The clinical features of the patients are described in detail. A missense mutation in UBA1 (c.T1499C; p.Ile500Thr) was identified as the probable cause of the non-Kennedy SBMA in the pedigree. Like AR, UBA1 is positioned on chromosome X. UBA1 is a highly conserved gene. It encodes ubiquitin-like modifier activating enzyme 1 (UBA1) which is the major E1 enzyme of the ubiquitin-proteasome system. Interestingly, UBA1 mutations can also cause infantile-onset X-linked spinal muscular atrophy (XL-SMA). The mutation identified here and the XL-SMA causative mutations were shown to affect amino acids positioned in the vicinity of UBA1's ATP binding site and to cause structural changes. CONCLUSION: UBA1 was identified as a novel SBMA causative gene. The gene affects protein homeostasis which is one of most important components of the pathology of neurodegeneration. The contribution of this same gene to the etiology of XL-SMA is discussed.

Disability and Quality of Life After Talectomy for Arthrogryposis Multiplex Congenita.

BACKGROUND: Arthrogryposis multiplex congenita (AMC) is one of the causes of rigid and resistant clubfoot. Talectomy is considered as a primary or salvage procedure for recurrent equinovarus deformity in these patients. We conducted this study to assess patients with AMC who underwent talectomy for the correction of foot and ankle deformities in terms of health-related quality of life and disability. METHODS: Patients under 10 years of age with a primary diagnosis of AMC who underwent talectomy and attended follow-up for at least 5 years were included in this study. We also formed an age- and gender-matched control group consisting of 20 individuals without any foot-ankle problem in order to compare the measurements between the AMC and healthy groups. Oxford Ankle Foot Questionnaire (OxAFQ) was administered as a health-related quality of life instrument to objectively measure the disability of the pediatric patients. RESULTS: Twenty patients (10 girls, 10 boys) who underwent a total of 35 talectomy operations with an average follow-up of 7.2 years and a control group of 20 similarly aged unaffected children were included in the study. The mean OxAFQ scores were significantly lower in the AMC group than in the controls for all domains (physical, emotional, and school and play), especially for the one concerning satisfaction with footwear The presence of plantigrade foot and absence of forefoot supination were significantly associated with the physical and footwear domains of the OxAFQ scores. The presence of hindfoot varus, midfoot adductus, dorsal bunion, and having less than 10 degrees of dorsiflexion had no effect on the OxAFQ scores. CONCLUSION: In this study, we found that the major driving factors for satisfaction after talectomy for AMC were plantigrade foot and absence of forefoot supination. The mean OxAFQ scores were universally lower in the AMC group than controls. Finding comfortable footwear is a major concern for the AMC patients. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Hereditary benign telangiectasia: a case report.

Hereditary benign telangiectasia is an autosomal dominant inherited dermatosis with typical presentation of telangiectasia of the skin and lips. The cause is still unknown. It is a primary telangiectasia that develops during childhood without systemic symptoms. Clinically round, oval, dendritic, or punctate telangiectasias are present, mostly asymptomatic, and they may cause only aesthetic problems. Because a similar clinical picture can be seen in several other skin diseases that may manifest not only with vascular lesions of the skin but also with systemic involvement and possible serious complications, we must be aware of all differential diagnostic possibilities. We present the case of a 37-year-old patient with hereditary benign telangiectasia to emphasize the importance of establishing the correct diagnosis and presenting proper information about the disease in a patient with telangiectasia of the skin.

Improvement of Pulmonary Function in Arthrogryposis Multiplex Congenita Patients Undergoing Posterior Spinal Fusion Surgery for Concomitant Scoliosis: A Minimum of 3-Year Follow-up.

OBJECTIVE: We sought to investigate the long-term outcome of pulmonary function for arthrogryposis multiplex congenita (AMC) patients undergoing posterior spinal fusion (PSF) and to further determine influential factors. METHODS: Eighteen AMC patients with a minimum of 3-year follow-up after PSF were prospectively collected. All the patients underwent a pulmonary function test before surgery and at the final follow-up. The percentage predicted values of vital capacity (VC%) and forced vital capacity (FVC%) were recorded. The following radiographic parameters were collected including Cobb angle and thoracic kyphosis. The total lung volumes (TLV) were measured on the image of 3-dimensional computed tomography scan by the reconstruction software. RESULTS: There were 10 males and 8 females with a mean age of 13.8 ± 6.1 years. The mean preoperative VC% and FVC% were 40.5% ± 7.6% and 39.5% ± 4.7%, which were significantly increased to 52.0% ± 7.5% and 51.2% ± 6.8% at the final follow-up (P < 0.001). Besides, there was remarkable improvement in terms of TLV (1.57 ± 0.2 L vs. 2.39 ± 0.6 L, P < 0.001). Remarkable correlations were observed between TLV and pulmonary function tests (r = 0.79, P < 0.001 for VC%; r = 0.78, P < 0.001 for FVC%). Multiple regression analysis showed that 2 variables including Δ thoracic kyphosis and Δ Cobb angle were independently associated with the improvement of pulmonary function. CONCLUSIONS: The pulmonary function of AMC patients can be well improved through PSF surgery. It was remarkably associated with the correction of curve magnitude and restoration of thoracic kyphosis.

Total joint replacement of the hip and knee in patients with arthrogryposis multiplex congenita: a report of six joints.

INTRODUCTION: Arthrogryposis multiplex congenita (AMC) is a rare congenital condition that leads to severe joint contractures and deformities. As painful joint dysplasia and degeneration might develop over time, total joint replacement (TJR) can be a potential treatment option for these patients. The aim of this study is to investigate functional results, implant survivorship and potential complications in patients with AMC who undergo hip or knee arthroplasty. MATERIALS AND METHODS: We retrospectively identified six TJR in three patients at a single centre performed between 2006 and 2019. The median patient age at surgery was 23 years and the median follow-up period was 69 (IQR 55-99) months. We analysed surgical technique, implant survivorship and complications as well as functional outcome determined by pain reported on the Numerical Rating Scale (NRS), patient-reported outcome scores [Oxford Hip Score (OHS), Harris Hip score (HHS), Oxford Knee Score (OKS)], range of motion and ambulatory status. Depending on data distribution means with ranges and median with interquartile range were compared with the Wilcoxon signed rank test or Student's t test. The level of significance was defined at < 0.05. RESULTS: In hips, the mean range of motion in flexion/extension (52° vs. 85°, p = 0.014) and in rotation (28° vs. 68°, p = 0.02) as well as mean pain score on the NRS (8.5 vs. 0, p = 0.001), OHS (9 vs. 26, p = 0.031) and HHS (17 vs. 52, p = 0.007) significantly improved. In knees, mean range of motion (55° vs. 93°, p = 0.403), mean pain score on the NRS (0 vs. 7) and the OKS (2 vs. 21) also improved. While the ambulatory status did not change, the patients who were wheelchair dependent reported less problems with transfers to a bed or chair and the patient who ambulated reported an improved walking distance. One total knee arthroplasty (TKA) underwent revision for an acute, late infection 155 months following the initial surgery. CONCLUSIONS: TJR is a safe procedure in patients with AMC that effectively improves function and reduces pain irrespective of preoperative ambulatory status.