Osteoid osteoma appearing after bony fracture in a girl with osteogenesis imperfecta.

Osteoid osteoma (OO) is a common, benign bone tumor. However, there are no case reports of OO associated with osteogenesis imperfecta (OI), or pathological fractures in OO. A 3-year-old girl with OI sustained a complete right tibial diaphyseal fracture. Bony fusion was completed after 4 months of conservative therapy; nevertheless, 18 months later spontaneous pain appeared at the fracture site, without any cause. Plain radiographs showed a newly apparent, rounded area of translucency 1 cm in diameter, just overlapping the previous fracture. Images obtained using three-dimensional time-resolved contrast-enhanced magnetic resonance angiography showed strong central enhancement in the early phase, with an apparent nidus, suggesting the diagnosis of OO. Nineteen months after the first fracture, while skipping, the patient refractured her tibial diaphysis at the site of the previous fracture. This is a very rare case of OO, apparently co-existing with OI and leading to a bony fracture. In our case, the combination of bone fragility in OI and a recent fracture at the site of the OO may have caused the re-fracture.

Opponensplasty With Abductor Pollicis Brevis Rerouting for Types II and IIIA Hypoplastic Thumbs.

PURPOSE: To evaluate the functional results after opponensplasty using an abductor pollicis brevis rerouting technique in type II and IIIA hypoplastic thumbs. METHODS: Eleven hypoplastic thumbs in nine children with type II and IIIA hypoplastic thumbs were treated with abductor pollicis brevis rerouting. The mean follow-up period was 70 months (range, 12-172 months). We assessed preoperative to postoperative changes in the angles of the first and second metacarpal axes and the longitudinal axis of the first metacarpal and proximal thumb phalanx as well as grip and pinch strengths. RESULTS: The mean angle of the first and second metacarpal axes showed a significant improvement to 64° (range, 47° to 89°), and the mean angle of the first metacarpal and proximal phalanx of the thumb showed a significant reduction to 8° (range, 1° to 21°) after surgery. The mean postoperative grip and pinch strengths were 77% (range, 63% to 106%) and 72.0% (range, 33% to 97%), respectively, relative to the unaffected side. CONCLUSIONS: Abductor pollicis brevis rerouting for type II and IIIA hypoplastic thumbs can produce joint stability and a strong pronation effect in addition to the opponens function. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.

Expression levels and DNA methylation profiles of the growth gene SHOX in cartilage tissues and chondrocytes.

All attempts to identify male-specific growth genes in humans have failed. This study aimed to clarify why men are taller than women. Microarray-based transcriptome analysis of the cartilage tissues of four adults and chondrocytes of 12 children showed that the median expression levels of SHOX, a growth gene in the pseudoautosomal region (PAR), were higher in male samples than in female samples. Male-dominant SHOX expression was confirmed by quantitative RT-PCR for 36 cartilage samples. Reduced representation bisulfite sequencing of four cartilage samples revealed sex-biased DNA methylation in the SHOX-flanking regions, and pyrosequencing of 22 cartilage samples confirmed male-dominant DNA methylation at the CpG sites in the SHOX upstream region and exon 6a. DNA methylation indexes of these regions were positively correlated with SHOX expression levels. These results, together with prior findings that PAR genes often exhibit male-dominant expression, imply that the relatively low SHOX expression in female cartilage tissues reflects the partial spread of X chromosome inactivation into PAR. Altogether, this study provides the first indication that sex differences in height are ascribed, at least in part, to the sex-dependent epigenetic regulation of SHOX. Our findings deserve further validation.

Non-vascularized metatarsal transfer for thumb hypoplasia: a medium- to long-term retrospective study of 41 patients.

LEVEL OF EVIDENCE: III.

Postoperative deviation in Wassel types II and III radial polydactyly: a retrospective analysis of 73 thumbs.

This study examined the relationship between osteochondral stability and postoperative deviation at the interphalangeal (IP) joint in Wassel types II and III radial polydactyly. Cases with cartilaginous fusion between the radial distal phalanx and the proximal phalanx were classified as type IIB, while the remaining cases were categorized as type IIA. In conventional surgery, the cartilage was routinely resected on the radial aspect of the proximal phalangeal head, while in the modified procedure, this was preserved to avoid postoperative radial deviation. Postoperatively, there was no significant difference between both procedures in type IIA thumbs regarding IP joint deviation, whereas in type IIB/III thumbs, IP joint deviation was significantly higher in the conventional group (mean 19° [SD 16°]) compared to the modified group (mean 0.8° [SD 4.9°]). Surgeons should exercise caution against excessive cartilage excision to preserve osteochondral stability during procedures, especially for type IIB and III radial polydactylies.Level of evidence: IV.

A neonate with multiple hand flexor tendon ruptures due to methicillin-susceptible Staphylococcus aureus sepsis: a case report.

BACKGROUND: Neonatal pyogenic tenosynovitis is a highly emergent soft tissue infection. We report a case of a neonate with pyogenic tendinopathy and tendon rupture diagnosed by ultrasonography (US). He subsequently developed pyogenic arthritis and osteomyelitis during antimicrobial therapy. CASE PRESENTATION: A 7-day-old boy was admitted to our hospital with redness and swelling of the right index finger. US on admission showed rupture of the flexor tendon of the right index finger with inactivity. The day after admission, he developed pyogenic arthritis of the right elbow and, subsequently, pyogenic osteomyelitis. Staphylococcus aureus was identified through bacterial culture, and the patient was treated with intravenous antibiotics for 6 weeks. However, after discharge from our hospital, rupture of the flexor tendon of the left thumb was confirmed. A two-stage flexor tendinoplasty was completed at the age of 2 years and 1 month for the flexor tendon rupture on his right index finger. CONCLUSIONS: In addition to blood culture, ultrasonographic evaluation should be performed in neonates with erythematous and swollen joints to identify the focus of infection as soon as possible. Moreover, repeated regular US examination is important in the follow-up of bone and soft tissue infections.

Late displacement after lateral condylar fractures of the humerus.

BACKGROUND: Nondisplaced or slightly displaced lateral condyle fractures may subsequently displace if treated with cast immobilization alone, and displacement indicates surgery. In this context, placing the forehand in pronation is sometimes recommended, and the prediction of the late displacement based on the presence of the fat pad sign is useful. However, few studies have quantitatively shown the relationships between forearm position during immobilization and late displacement and between the presence of the fat pad sign and late displacement. We investigated the factors that may affect the late displacement and the features of the consequences during the late displacement. METHODS: Between October 2003 and July 2020, we observed 62 patients (45 boys and 17 girls). We evaluated the correlation between the factors age, gender, the initial displacement, the presence of a fat pad sign, the flexion angle of the elbow, the forearm position (pronation or neutral), and the late displacement on day 7 after the injury, which means the difference between the displacement on day 0 and that on day 7 in the 62 cases with the minimal displacement. Moreover, of all 62 cases observed, we further investigated those 52 cases that had been treated conservatively for 3 weeks for any resultant effects. We used the Friedman test to evaluate the difference in the late displacement on each day. We acknowledged the P value < .05 as significant. RESULTS: There was no significant correlation between each factor (age, sex, initial displacement, presence of the fat pad sign, flexion angle of the elbow, or forearm position) and displacement on day 7, whereas there was significant progressive displacement until day 7. CONCLUSION: The present study concluded that late displacement would happen until the 7 postoperative dates, regardless of the splint angle, the fat pad sign, the age, or the gender. Therefore, it is important to follow any case, even with mild-displaced lateral condylar humeral fractures, until day 7 because the late displacement might occur.

Abductor pollicis brevis rerouting and first web deepening for clasped thumb deformity in arthrogryposis multiplex congenita.

LEVEL OF EVIDENCE: III.

Functional and Cosmetic Reconstruction of Floating Thumb: A Thumb-preserving Technique.

For the severely hypoplastic thumb, including floating thumb, it is difficult to acquire function while preserving the thumb. Pollicization using the index finger after removing the hypoplastic thumb is usually indicated for such cases. However, most parents of children undergoing surgery for deformed hands desire retaining the digit number, 1 thumb and 4 fingers. A floating thumb has a neurovascular band in its pedicle, and we can identify and divide the band with precision for preservation, although it seems impossible to retain it. For acquiring function while retaining the thumb, we developed carpometacarpal arthroplasty of the floating thumb. For the first stage, the fourth metatarsal head was transferred to the first metacarpal base, followed by third metatarsal half-slip transfer to the space of the excised fourth metatarsal head with the first web plasty using a dorsal sliding flap. Second stage surgery was performed ∼6 months after the first stage. For creating stable opponensplasty, the abductor digiti minimi tendon was anchored to the ulnar side of the metacarpophalangeal joint; for extension, extensor indicis proprius transfer to the hypoplastic extensor pollicis longus tendon was performed; for flexion, ring finger flexor digitorum superficialis transfer to the hypoplastic flexor pollicis longus tendon was performed. In general, the functional results were acceptable with a high degree of family satisfaction, although in some cases function was limited to simple object holding. We explain the surgical procedures to preserve the thumb while gaining function as well as appearance using high-quality illustrations, figures, and videos. This should be helpful for surgeons who want children with hypoplastic thumbs to have both 5 digits and reasonable functional ability.

Characteristics of Cubitus Varus Deformity after Lateral Condylar Fracture of the Humerus.

Background: Lateral humeral condylar fractures often heal with some residual elbow deformity. However, details of angulation or tilting angle of the lateral condyle after the fracture have not been evaluated so far. Methods: Between 2008 and 2016, we followed up 80 mild fractures of the lateral humeral condyle for more than a year. Thirty fractures were treated by open reduction and internal fixation (ORIF) with Kirschner wires. Fifty cases were treated with a long arm splint for 3 weeks (Fig. 1). The average age of the patients at the time of the injury was 5.5 years. The humerus-elbow-wrist angle (HEWA), Baumann's angle (BA), and tilting angle (TA) were measured on the radiographs. The active range of motion (ROM) was clinically assessed at unaffected and affected sides at the final follow-up. Results: No significant differences were detected between the sides about TA or ROM at the final follow-up. However, HEWA/ BA showed more significant loss of correction. There were significant differences in BA at the affected side between the ORIF and splint groups. Conclusions: Cubitus varus deformity after lateral humeral condylar fracture is not accompanied by a change in TA or ROM, unlike the deformity after supracondylar or distal epiphyseal fracture of the humerus (Fig. 2). Operative treatment to precisely correct and fix the lateral condylar fracture still retained some cubitus varus deformity, although it might lessen or prevent the deformity when compared to conservative treatment with a splint.

Treatment for Wassel Types V and VI Thumb Polydactyly.

Background: Polydactyly of the thumb is the most common congenital anomaly of the hand, but there have been few reports regarding Wassel types V and VI. The purpose of this study is to present our surgical strategies and outcomes for cases of Wassel types V and VI polydactyly of the thumb. Methods: Twenty-nine thumbs of 29 patients were included in this study; 17 cases were Wassel type V and 12 cases were type VI. Our strategies for initial surgery were appropriate tendon and muscle relocations. Opponensplasty with the abductor digiti minimi or the flexor digitorum superficialis and osteotomy were not performed in the initial surgery. We evaluated pinch motion ability and the number of additional surgical procedures. The first web space and radial instability of the metacarpophalangeal (MCP) joint were measured by radiography while the patient held a polystyrene foam cone. Results: Twenty-two patients were able to perform a pulp pinch. Narrowing of the first web defined as the angle between the first and second metacarpus (1-2 MCA) < 40° occurred in five cases. Radial instability of the MCP joint defined as the angle between the first metacarpus and thumb proximal phalanx (1 MPA) > 20° occurred in seven cases. Additional surgery was performed in seven cases (24%) to improve insufficient thumb opposition, radial instability of the MCP joint, and narrowing of the first web. Patients in all reoperation cases were able to perform a pulp pinch. Conclusions: Our strategies for initial surgery often had satisfactory outcomes, but careful follow-up observations and appropriate reoperation for cases with poor initial outcomes were more important.

Radial Longitudinal Deficiency: Severity Differences Between U.S. and Japanese Cohorts.

PURPOSE: Radial longitudinal deficiency (RLD) presents on a spectrum of severity and associated diagnoses. The literature is limited in describing patient presentation without comparative data between countries. In a study comparing 2 cohorts of patients, 1 in the United States and 1 in Japan, we hypothesized that there would be a similar presentation of forearm deficiency severity, thumb hypoplasia severity, and associated syndromes between the 2 cohorts. METHODS: Patients with RLD were identified via a comprehensive chart review at 2 pediatric hospital cohorts, 1 in the United States and 1 in Japan, capturing patients presenting over 15 years. We assessed RLD and thumb hypoplasia severity via a modified Bayne and Klug and modified Blauth classifications. The relationship between these 2 diagnoses and the presence of common medical conditions were evaluated and correlated. RESULTS: A total of 194 Japanese patients with 290 involved extremities were compared with 107 U.S. patients with 174 involved extremities. The U.S. cohort had a significantly more severe RLD, and a higher rate of bilaterality (63% vs 50%, respectively). A total of 131 Japanese patients (68%) and 41 U.S. patients (38%) had associated medical syndromes/associations, most frequently vertebral abnormalities, anal atresia, cardiac abnormalities, tracheoesophageal fistula and/or esophageal atresia, renal agenesis and dysplasia, and limb defects (VACTERL; 46 Japanese, 14 U.S.), Holt-Oram (44 Japanese, 5 U.S.), and thrombocytopenia absent radius syndrome (0 Japanese, 12 U.S.). Correlation analysis showed that increased RLD severity was associated with increased thumb hypoplasia severity in both groups, with 95% of modified Bayne and Klug III, IV, or V patients having severely affected thumbs (type IIIb, IV, or V). CONCLUSIONS: The U.S. patients had a more severe RLD and a higher rate of bilaterality. Japanese patients had a higher incidence of associated syndromes and radial polydactyly. Both cohorts showed that increased forearm severity was associated with more severe thumb hypoplasia. TYPE OF STUDY/LEVEL OF EVIDENCE: Differential diagnosis/symptom prevalence study III.

Variation of Extrinsic Tendons of the Thumb in Type IIIA Hypoplastic Thumbs.

PURPOSE: The purpose of this study was to identify the variety of anatomical abnormalities of extrinsic tendons in type IIIA hypoplastic thumbs. METHODS: We reviewed 79 thumbs in 67 patients. Opponensplasty, stabilizing of the thumb metacarpophalangeal joint, and widening of the first web space were performed in all patients. At the time of surgery, we made detailed observations of the anatomical abnormalities of the extrinsic tendons of the thumb. RESULTS: Fifty thumbs (50 of 79; 63%) had an interconnection between the flexor pollicis longus (FPL) and the extensor pollicis longus (EPL) tendons. Twenty-six thumbs (26 of 79; 33%) had bifurcations (25 [32%] bifurcated from the FPL; 1 [1%] bifurcated from the EPL). There were 25 FPL abnormalities (4 [5%] complete absence; 8 [10%] proximal absence; 2 [3%] distal absence; 11 [14%] tendon hypoplasia) and 7 EPL abnormalities (2 [3%] proximal absence; 5 [6%] tendon hypoplasia). CONCLUSIONS: Interconnections between the FPL and the EPL tendons and a duplicated FPL were observed frequently. CLINICAL RELEVANCE: The present study investigates the detailed anatomy of the type IIIA hypoplastic thumbs. The data might help improve the design of surgical procedures.

Preservation of the Epiphysis and Growth Plate in the Surgical Management of Femoral Osteosarcoma in a Skeletally Immature Patient by Intercalary Resection and Biological Reconstruction: A Case Report.

Osteosarcoma arises most frequently in the metaphysis around the knee and its management by limb salvage surgery in skeletally immature pediatric patients is extremely challenging. Common reconstructive methods such as endoprosthetic or biological reconstruction are not fully capable of dealing with durability-related and growth-related problems and their functional outcomes are not as good as those seen in adult cases. A definitive limb salvaging procedure in children that outperforms amputation or rotationplasty has not yet been established. Herein, we report a case of stage IV osteosarcoma in the femur of a 7-year-old boy that was safely managed with intercalary resection preserving the distal femoral growth plate and epiphysis, followed by biological reconstruction using a frozen tumor-devitalized autograft. Good response to preoperative chemotherapy and the diaphyseal location of the tumor enabled us to perform a tumor resection that spared the growth plate and preserved the native knee joint structure. Plate fixation over the growth plate was terminated by removing the locking screws in the epiphysis after 44 months, which restored growth capacity to some extent. At 50 months postoperatively, no recurrence or progression of the disease was observed. The patient uses an extension shoe and reports having little discomfort in his daily life despite having a restricted range of motion and limb length discrepancy. In conclusion, limb salvage with biological reconstruction in skeletally immature patients can provide an acceptable functional outcome, including minimized limb length discrepancy, if critical damage to the growth plate and articular components can be avoided.

A male Korean who was diagnosed with chronic enteropathy associated with SLCO2A1 (CEAS): case report with literature review.

OBJECTIVE: To further disseminate the nomenclature of chronic enteropathy associated with SLCO2A1 (CEAS), especially for physicians in China and Korea where the genetic feature of SLCO2A1 gene mutations related hypertrophic osteoarthropathy and pachydermia had been extensively studied. SLCO2A1 gene mutations related hypertrophic osteoarthropathy and pachydermia had been extensively studied. DESIGN: A case report with literature review of SLCO2A1 gene mutations-related disorders. RESULTS: A 38-year-old Korean presented to a tertiary hospital with dizziness, abdominal pain and melena. He had a positive faecal occult blood test on initial workup. Oesophagogastroduodenal endoscopy (OGD), colonoscopy and CT scan were unremarkable and showed no obvious cause for his melena. Capsule endoscope and roentgen barium studies were performed, revealing an erythematous mucosa with ulcers in the jejunum and stenosis to the jejunal-ileal junction. Next-generation sequencing was then performed and discovered point mutations of SLCO2A1 gene's seven exon (940+1 G>A) and 13 exon (1807 C>T) allele. This Korean patient with CEAS is the first documented case noted outside of the Japanese population. CONCLUSION: CEAS is not uniquely found in Japanese individuals. There are lots of similarities between CEAS and primary hypertrophic osteoarthropathy, the two entity may just be the two sides of one same coin. International and multidisciplined efforts are required to further study this complicated disorder.

Pronounced femur malunion after pathological bone fracture due to a simple bone cyst in the shaft of the femur, treated using Ilizarov fixation: a case report.

BACKGROUND: Although a simple bone cyst carries the risk of pathological fractures, it rarely causes severe deformity. Here we report a case of severe femoral deformity after multiple pathological fractures due to simple bone cysts, and consider the reason for the progression of malunion despite multiple previous treatments. Finally, we propose a treatment option for malunion correction. CASE PRESENTATION: A 9-year, 7-month-old Japanese girl was referred to our facility with obvious deformity of her right femur, caused by multiple simple bone cyst-related pathological fractures. The deformity included bowing of approximately 90° and an internal rotation of 60° in the middle third of the femoral shaft. To correct this deformity, we excised the lesion, thus shortening the femur, then corrected the alignment and applied an Ilizarov fixator to extend the bone. At present, 3 years after surgery, the deformity has not recurred and our patient is living without any limitations in daily activities or regular exercise. CONCLUSIONS: When a long bone is in a prolonged state of deformation, the deformity not only progresses as the bone grows, but the soft tissues remain unbalanced and treatment becomes increasingly difficult. To prevent increasing bone deformity and fragility, the deformity should be corrected as quickly as possible using intramedullary nailing or other fixation techniques. We believe that our shortening-distraction method is effective for the treatment of severe deformity with unbalanced soft tissues.