Nusinersen Initiation After Onset of Weakness Does Not Prevent Progression of Hip Instability.

BACKGROUND: We report changes in the natural history of hip instability with nusinersen treatment among patients with spinal muscular atrophy (SMA) type II after onset of weakness, historically wheelchair-bound but now potentially ambulatory in the era of disease-modifying therapy. METHODS: Patients with genetically confirmed diagnoses of SMA type II who received intrathecal nusinersen from January 1, 2018, to June 30, 2022, were screened for inclusion. Patients with less than 6 months of follow-up, or prior hip surgeries were excluded. Primary clinical outcome measures included scores from Hammersmith motor functional scale expanded (HMFSE), revised upper limb module (RULM), 6-minute walk test (6MWT), and ambulatory status. Radiographic outcomes, including Reimer migration index, the presence of scoliosis, and pelvic obliquity, were also assessed. Secondary outcomes involved comparisons with a historical cohort of SMA type II patients treated at our institution who never received nusinersen. RESULTS: Twenty hips from 5 boys and 5 girls were included in the analysis, with a mean follow-up of 3 years and 8 months. The median age at time of nusinersen initiation was 6.8 years old, ranging between 2.5 and 10.3 years. All patients developed lower limb motor weakness before nusinersen initiation. After treatment with nusinersen, 1 previously stable hip (5%) developed subluxation, 15 hips (75%) remain subluxated, 3 hips (15%) remain dislocated, and 1 hip (5%) remained stable, with a statistically significant difference between the pretreatment and posttreatment groups ( P <0.01). Six patients (60%) were ambulatory at latest follow-up. Six patients (60%) had improved ambulatory ability; 2 had static ambulatory ability (20%); and 2 had deterioration in their walking ability. The median HFMSE score improved from 18.5 (range 0 to 46) to 22 (range 0 to 49) ( P =0.813), whereas the median RULM score improved from 17 (range 2 to 28) to 21.5 (range 5 to 37), which was statistically significant ( P =0.007). CONCLUSIONS: Hip instability persists despite treatment with nusinersen among patients with SMA type II who received nusinersen after onset of lower limb weakness. LEVEL OF EVIDENCE: Therapeutic Level IV.

Fibrodysplasia ossificans progressiva in Hong Kong-A case report series.

Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare condition. The diagnosis could be challenging due to its rarity and non-specific presenting symptoms. However, early diagnosis and appropriate management help in preserving patients' function and quality of life. Herein, we report the diagnostic journeys and clinical courses of 8 patients with FOP in Hong Kong and illustrate the challenges involved.

Quality of Surgery and Patient Selection Are Keys to Success in Hip Stabilization Surgery in Cerebral Palsy.

BACKGROUND: Cerebral palsy patients are at risk of hip instability, to which various soft tissue and bony surgeries are performed should conservative management fail. We aim to identify factors associated with treatment failure to guide surgical management. METHODS: Cerebral palsy patients treated at 2 university-affiliated tertiary pediatric orthopaedic referral centers with hip stabilization surgery performed for subluxation in 1998 to 2015 with minimum of 5 years follow-up were reviewed. Failure was defined as reoperation to the same hip because of recurrent subluxation. Age, sex, Gross Motor Function Classification System level, tone abnormality, operation type, Reimer's migration index (RMI), and acetabular index (AI) were assessed. Cut-off values were identified through Youden index on receiver operating characteristic curve. RESULTS: Eighty-nine hips from 55 patients with mean follow-up of 12.4 years were analyzed. Revision surgery was performed in 14 hips. Postoperative hip subluxation (P<0.001) and acetabular dysplasia (P=0.001) were predictive of failure, with postoperative RMI conferring an adjusted hazard ratio of 1.13 (95% confidence interval: 1.08-1.19, P<0.001) on multivariable survival analysis. Achieving a postoperative RMI of <27.5% predicts success with 92.9% sensitivity and 72% specificity with area under curve of 0.916 (P<0.001), while postoperative AI of <23.1 degrees predicts success with 92.3% sensitivity and 62.2% specificity with area under curve of 0.796 (P=0.001). In subgroup analysis of soft-tissue-only procedures, RMI >44% preoperative and >32% postoperative were associated with reoperation. In femur-only osteotomies, preoperative RMI >48% and postoperative RMI >28% were associated with failure. In pelvic and combined osteotomies, postoperative RMI >32% and AI >30 degrees were associated with failure. Other factors analyzed were not associated with reoperation. CONCLUSIONS: Patient selection and quality of surgery in terms of residual postoperative hip subluxation and acetabular dysplasia are associated with need for remedial surgery. Soft-tissue-only procedures should aim to correct RMI to <32%. Bony surgery should be considered when preoperative RMI >44%, and pelvic osteotomies if RMI >48%. Pelvic osteotomies should target postoperative RMI <32% and AI <30 degrees. LEVEL OF EVIDENCE: Level II-prognostic study.

Surgical applications of three-dimensional printing in the pelvis and acetabulum: from models and tools to implants.

There are numerous orthopaedic applications of three-dimensional (3D) printing for the pelvis and acetabulum. The authors reviewed recently published articles and summarized their experience. 3D printed anatomical models are particularly useful in pelvic and acetabular fracture surgery for planning, implant templating and for anatomical assessment of pathologies such as CAM-type femoroacetabular impingement and rare deformities. Custom-made metal 3D printed patient-specific implants and instruments are increasingly being studied for pelvic oncologic resection and reconstruction of resected defects as well as for revision hip arthroplasties with favourable results. This article also discusses cost-effectiveness considerations when preparing pelvic 3D printed models from a hospital 3D printing centre.

Long-term outcome after Lambrinudi arthrodesis: How they're doing after three decades.

OBJECTIVE: The aim of the study is to investigate the long-term outcome of patients who received Lambrinudi arthrodesis for severe equinovarus deformities. METHODS: This is a single-center, retrospective study of patients who received Lambrinudi triple arthrodesis of the foot. Both clinical and radiological information were analyzed. RESULTs: We were able to review 10 patients suffering from severe equinus deformities mostly as a result of or in association with poliomyelitis (8 of 10) who received Lambrinudi arthrodesis. The majority (7 of 10) of our patients had fair to good outcome at an average follow-up of 37 years. Specifically, six of eight polio patients had fair to good outcome. Of the X-rays available for assessment, the majority of patients showed radiological signs of adjacent joint arthritis; however, the presence of such did not invariably lead to poor clinical outcome. CONCLUSION: Lambrinudi arthrodesis is a treatment option with favorable long-term outcome for patients with severe, fixed equinus deformities.

A previously unreported type of extra-articular triplane fracture: A revised classification system.

BACKGROUND: Atypical triplane fractures are defined as triplane fractures that are intra-articular but affect the non-weight-bearing area of the tibia plafond or extra-articular triplane fractures where the epiphyseal fracture line exits outside the articulating cortex of the medial malleolus. These fractures are scarcely reported in the literature. Here, we study the fracture pattern, mechanisms, and recommendations for management. METHODS: This is a retrospective study of all triplane fractures identified from 2012 to 2016 in a tertiary referral center. There were 10 atypical triplane fracture patterns identified in this cohort. All patients were followed up with an average of 19 months. A modified atypical triplane fracture classification was devised and compared with previously reported classification systems. Clinical outcomes measured included treatment complications, ankle range of motion, and time needed to return to sports. RESULTS: We identified a new extra-articular triplane fracture variant with an anteromedial epiphyseal sleeve fragment (fracture variant). There were no long-term complications from operative closed reduction and percutaneous screw fixation. Operative cases had earlier ankle mobilization and regained full range of motion (12.8 weeks vs 13.3 weeks) earlier. The average time to return to sports was 5.2 months. CONCLUSIONS: We propose a modified classification for atypical triplane fractures and recommend closed reduction and percutaneous screw fixation for displaced atypical triplane fractures. LEVEL OF EVIDENCE: IV (Case Series).

Somatic PIK3CA mutations in seven patients with PIK3CA-related overgrowth spectrum.

Somatic mutations in PIK3CA cause many overgrowth syndromes that have been recently coined the "PIK3CA-Related Overgrowth Spectrum." Here, we present seven molecularly confirmed patients with PIK3CA-Related Overgrowth Spectrum, including patients with Congenital Lipomatous Overgrowth, Vascular Malformations, Epidermal Nevi, Scoliosis/Skeletal and Spinal syndrome, Klippel-Trenaunay syndrome, lymphatic malformation and two with atypical phenotypes that cannot be classified into existing disease categories. The literature on PIK3CA-Related Overgrowth Spectrum, suggests that PIK3CA c.1258T>C; p.(Cys420Arg), c.1624G>A; p.(Glu542Lys), c.1633G>A; p.(Glu545Lys), c.3140A>G; p.(His1047Arg), and c.3140A>T; p.(His1047Leu) can be identified in approximately 90% of patients without brain overgrowth. Therefore, droplet digital polymerase chain reaction targeting these mutation hotspots could be used as the first-tier genetic test on patients with PIK3CA-Related Overgrowth Spectrum who do not have signs of overgrowth in their central nervous system. © 2017 Wiley Periodicals, Inc.

Normal radiographic parameters in paediatric pelvic radiographs from a Chinese population.

Paediatric pelvic and hip radiographs are a common investigation used when assessing a child for suspected developmental dysplasia of the hip. This report describes an attempt to establish normal values of medial joint space, acetabular index and centre edge angle according to specific age groups and sex in a Chinese population. Patients who had undergone a pelvic radiograph as part of their assessment, but were subsequently found to have normal hips were recruited retrospectively. These patients were grouped according to sex and age; medial joint space, acetabular index and centre edge angle were measured in all radiographs. A mean±SD was calculated for each group, and then each age group was tested for statistical significance between the male and the female groups. A total of, 98 patients were recruited, who underwent 188 pelvic radiographs, resulting in images of 376 'normal' hips. The results for medial joint space, acetabular index and centre edge angle for each age and sex group are described. Only the acetabular index requires different reference ranges for male and female patients because of consistent statistical significance between the two groups. It was found that medial joint space remained fairly constant throughout the age groups, whereas the acetabular index decreased and the centre edge angle increased slightly. The reference ranges for the parameters described here are quite different from those established previously in a population of Northern-European descent, which could be because of a variety of reasons including genetics, body habitus and measurement technique. We believe that it would be prudent to implement these different ranges when assessing patients of Chinese heritage to optimize care of patients who may suffer as a consequence of not receiving treatment for missed hip dysplasia. LEVEL OF EVIDENCE: Diagnostic Study Level III - Study of nonconsecutive patients (without consistently applying the reference 'gold' standard).

Management pitfalls of fractured neck of femur in osteogenesis imperfecta.

INTRODUCTION: Fractured neck of femur in osteogenesis imperfecta is rarely reported. Its management is always difficult because of bone fragility and the outcome is not well known. We, therefore, aimed to study the management pitfalls in this group of patients. METHODS: We retrospectively reviewed five cases of fractured neck of femur in four patients treated in our hospital between 2006 and 2009. The demographic data, mode of injury, fracture configuration, treatment, complications, clinical and radiological outcome were reviewed. RESULTS: According to the Sillence classification, one patient was type I, two were type III and one was type IV. There were two children (aged 8 and 15 years) and two adults (aged 21 and 22 years), with the 8 year-old girl suffering from hip fracture on different sides in two accidents. All five hip fractures were the result of low-energy injury and were associated with other fractures. Two undisplaced fractures required intra-operative fluoroscopic confirmation to demonstrate movement at the fracture site. The interval between the injury and fixation ranged from 6 h to 3 days. One hip required secondary surgery to openly reduce the fracture due to inadequate primary fixation and reduction. Two hips were fixed with paediatric dynamic hip screws and three hips were fixed with cannulated screws. All patients were immobilised in hip spica for 6 weeks. The average follow-up was 4 years (3-5 years). All patients had satisfactory union and none of them developed radiological evidence of avascular necrosis at the latest follow-up. All patients returned to their pre-injury functional level. CONCLUSION: Fractured neck of femur is rare given the high prevalence of long bone fractures in osteogenesis imperfecta. They all have characteristic associated fractures of the extremity at the time of injury and neck of femur fractures could be easily missed. Fracture fixation is a great challenge to the orthopaedic surgeons because of the small size of the patients, poor bone quality with suboptimal imaging intra-operatively and compromised purchase of fixation devices. The choice of implants should be determined by the size of the patients and the presence of prior instrumentation close to the hip joint.

Pitfalls in diagnosing septic arthritis in Hong Kong children: ten years' experience.

OBJECTIVES: To evaluate the initial presentation of septic arthritis in Hong Kong children with respect to clinical and laboratory findings that can aid making a prompt diagnosis. DESIGN: Retrospective review. SETTING: Five public hospitals in Hong Kong. PATIENTS: Data concerning paediatric patients with septic arthritis were collected from January 2001 to December 2010. Patients with postoperative infections and those without enough retrievable information were excluded. RESULTS: Of 31 patients analysed, on admission only 52% had had a fever of <38.5°C and 71% had raised white blood cell count of <12 x 10(9) /L. In 74% of these patients, Gram stains of blood culture samples yielded no positive findings. The leading causative organism was Staphylococcus aureus (42%), followed by group A Streptococcus (23%). When group A Streptococcus was responsible, five out of seven patients had a complicated clinical course (repeated surgeries, Streptococcus-related organ failure, and chronic joint stiffness). Moreover, in 19% of instances, the empirical antibiotic therapy prescribed on admission did not provide a broad enough spectrum of cover. CONCLUSION: Signs of sepsis such as high fever, raised white blood cell count, and positive Gram smear from blood cultures were only present in around half of these patients with septic arthritis. Furthermore, group A Streptococcus tended to produce many complications. Regrettably, about a quarter of the empirical antibiotic regimens started by frontline staff were deemed not have a broad enough spectrum of cover. Improvement in the initial detection and management of septic arthritis patients is warranted.

Antibiotic prophylaxis after total joint replacements.

OBJECTIVES: To review the latest evidence on antibiotic prophylaxis for patients with total joint replacements to prevent prosthesis infections. DATA SOURCES: Literature search of Medline and PubMed until June 2009. STUDY SELECTION: Studies of patients with total joint replacements from around the world, studies concerning antibiotic prophylaxis, as well as chemoprophylaxis guidelines from orthopaedic associations were searched. DATA EXTRACTION: Literature review, original articles, case reports, best practice guidelines. DATA SYNTHESIS: With the rising incidence of patients with total joint replacements, subsequent deep infection of the implants is a rare but dreaded complication which has immense physiological, psychological, financial, and social implications. Guidelines from urologists, gastroenterologists, and dental surgeons attempt to identify high-risk patients who may be more susceptible to prosthetic joint infections. These patients are provided with prophylactic antibiotics before any invasive procedure that may cause bacterial seeding to prosthetic joints. Most orthopaedic associations around the world adopt a similar policy to provide prophylaxis to cover any anticipated chance of bacteraemia. The American Association of Orthopaedic Surgeons adopts the most cautious approach in which all patients with total joint replacements who undergo any procedure that breaches a mucosal surface receive prophylactic antibiotics. CONCLUSION: The guidelines from the American Association of Orthopaedic Surgeons seem to have an all-encompassing policy when it comes to providing prophylactic antibiotics. Nonetheless, physicians must still exercise their judgement and customise the treatment to each patient. The benefits of prophylactic antibiotics must be balanced against the risks of drug side-effects and the emergence of antibiotic resistance.