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.

Resection Arthroplasty Is a Valuable Strategy for Humeroradial Synostosis - A Case Report.

A 15-year-old girl with humeroradial synostosis since birth underwent a resection arthroplasty. A trapezoidal resection osteotomy of approximately 2 cm was performed at the anterior part of the bone flexure. This resulted at 18 months in an elbow arc of motion of 60°-110° and forearm pronation/supination of 40° and 60° without postoperative complications and improved disabilities of the arm, shoulder and hand and Hand 20 scores. Radiographic analysis revealed a humeroradial joint with a maintained pseudarthrosis and hinged motion at the humeroulnar joint. When performed by an experienced surgeon, resection arthroplasty corrects humeroradial synostosis, resulting in improvement in range of motion and quality of life. Level of Evidence: Level V (Therapeutic).

Intercostal nerve transfer in management of biceps and triceps co-contraction in brachial plexus birth palsy.

OBJECTIVE: Brachial plexus birth palsy (BPBP) is often caused by traction during birth. In some cases, reinnervation occurs during spontaneous recovery and it causes involuntary co-contraction between antagonistic muscles. When it comes up between the biceps and triceps muscles, smooth active motion of the elbow joint is impaired. We are presenting outcomes of intercostal nerve (ICN) to radial nerve transfer to minimize elbow motion abnormality due to co-contraction. METHODS: We present five cases (two males and three females) of biceps and triceps co-contraction in BPBP patients treated from 2005 to 2018. The mean age at surgery was 9.36 years (range, 4.8-16.4 years). They were treated by ICNs transfer to motor branch of the radial nerve to the triceps muscle. Preoperative electromyography was done in all cases to confirm biceps and triceps co-contraction and to assess the contractile status of both muscles. A 10-s flexion extension test was done pre and postoperatively to assess the efficacy of our procedure. RESULTS: The postop course was uneventful. No donor site morbidity or respiratory complications were recorded in any patient. The mean postoperative follow-up period was 83.9 months (range, 53.6-135.5 months). At the final follow-up, elbow flexion was M4 in the Medical Research Council (MRC) grading scale in all five patients and elbow extension was graded M4 or M4- in all five patients. There was significant increase in the 10 s flexion extension test results delineating the effectiveness of the procedure. CONCLUSIONS: ICNs transfer to motor branch of the radial nerve to the triceps muscle for management of biceps and triceps co-contraction in BPBP is a good option with minimal morbidity and good success rate.

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.

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

LEVEL OF EVIDENCE: III.

Surgical Treatment of Ulnar Cleft Hand with All Fingers - A Report of Two Patients.

An ulnar cleft hand is a rare congenital deformity presenting with a cleft between the ring and little finger. It may be associated with the absence of a finger. The goals of treatment are cleft closure, increasing the length of the hypoplastic little finger and preservation of function. We report two patients with ulnar cleft hand without missing fingers. Both underwent cleft closure. One was treated by lengthening of the fifth metacarpal with an external fixator, and the other by finger translocation. Both patients achieved a near normal length of the little finger and a reasonable functional and aesthetic outcome. Level of Evidence: Level V (Therapeutic).

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 approaches for congenital transverse limb deficiency: Data analysis from an epidemiological national survey in Japan.

BACKGROUND: Congenital limb deficiency is a rare anomaly that impairs limb function. Transverse deficiency accounts for approximately half of congenital limb deficiency cases. In Japan, there have been no detailed data of clinical features, especially treatment approaches, of this disorder. The present study aimed to investigate the status of treatment approaches of congenital transverse limb deficiency in Japan. METHODS: From the national epidemiological survey of congenital limb deficiency undertaken in Japan in 2016, all the data of 200 patients with congenital transverse limb deficiencies were extracted. These data were analysed to reveal the treatment approaches of congenital transverse limb deficiency and its basic clinical features. RESULTS: Surgical treatments and prosthetic or orthotic intervention had been implemented or planned for about one-quarter of patients, respectively. In the upper limb deficiencies, prosthetic or orthotic intervention was likely chosen in cases of deficiency at the metacarpal or proximal to metacarpal level. Surgical treatment was chosen only in cases of deficiency at the carpal or distal to carpal level. Although the number of patients with transverse lower limb deficiencies was small, prosthetic or orthotic intervention was likely chosen in proximal deficiencies, and surgical treatment was likely chosen in distal deficiencies. CONCLUSIONS: Herein, we revealed the status of treatment approaches for congenital transverse limb deficiency in Japan. Approximately half of the patients had no history of-and no plans for-surgical, prosthetic, or orthotic interventions. Further treatment advances may enable patients with congenital limb deficiencies to increase their participation in daily activities. STUDY DESIGN: Cross-sectional survey.

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.

Assessment of hand function using the functional dexterity test after opponensplasty in young children with Blauth type 2 hypoplastic thumb.

The functional dexterity test (FDT) is a timed pegboard test based on the manipulation of each peg and suitable for young children as it is both simple and quick to perform. We assessed the postoperative FDT values for children with Blauth type 2 hypoplastic thumbs after opponensplasty. We evaluated hand function using FDT for 12 hands of 11 patients with Blauth type 2 hypoplastic thumbs. Opponensplasty was performed in all hands following by Huber's procedure. All patients were evaluated from 6 to 12 months after surgery for hand function using three types of FDT scores: time in seconds to complete the test (FDT time), combined total time with penalty seconds added to the initial time (FDT total), and the number of pegs per second to complete the task as a percentage against normative values (FDT speed). We compared the postoperative FDT scores with those for Blauth type 1 or 2 hypoplastic thumb patients without surgical treatment. FDT time and FDT total for the patients postoperatively were both significantly shorter than those in the type 2 patients without surgical treatment. FDT speed was significantly higher than that for the patients without surgical treatment. There were no significant differences in the three FDT scores between the postoperative patients and the type 1 patients. There were several limitations including small sample size, large ranges of the data, and high number of variables. FDT reflected postopponensplasty improvement in hand dexterity in young children with Blauth type 2 hypoplastic thumb.

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.

Comprehensive clinical and molecular studies in split-hand/foot malformation: identification of two plausible candidate genes (LRP6 and UBA2).

Split-hand/foot malformation (SHFM) is a clinically and genetically heterogeneous condition. We sequentially performed screening of the previously identified Japanese founder 17p13.3 duplication/triplication involving BHLHA9, array comparative genomic hybridization, and whole exome sequencing (WES) in newly recruited 41 Japanese families with non-syndromic and syndromic SHFM. We also carried out WES in seven families with nonsyndromic and syndromic SHFM in which underlying genetic causes including pathogenic copy-number variants (CNVs) remained undetected in our previous studies of 56 families. Consequently, we identified not only known pathogenic CNVs (17p13.3 duplications/triplications [n = 21], 2q31 deletion [n = 1], and 10q24 duplications [n = 3]) and rare variants in known causative genes (TP63 [n = 3], DLX5 [n = 1], IGF2 [n = 1], WNT10B [n = 3], WNT10B/PORCN [n = 1], and PORCN [n = 1]), but also a de novo 19q13.11 deletion disrupting UBA2 (n = 1) and variants that probably affect function in LRP6 (n = 1) and UBA2 (n = 1). Thus, together with our previous data based on testing of 56 families, molecular studies for a total of 97 families with SHFM revealed underlying genetic causes in 75 families, and clinical studies for the 75 families indicated a certain degree of correlation between genetic causes and phenotypes. The results imply that SHFM primarily occurs as a genetic disorder with genotype-phenotype correlations. Furthermore, the results together with previous data such as the development of SHFM in Lrp6 knockout mice, the presence of SHFM in two subjects with 19q13 deletions involving UBA2, and strong mouse Uba2 expression in the developing limb buds, imply that LRP6 and UBA2 represent plausible candidate genes for SHFM.

Development of a Parent Wireless Assistive Interface for Myoelectric Prosthetic Hands for Children.

In this study, a one-degree-of-freedom myoelectric prosthesis system was proposed using a Parent Wireless Assistive Interface (PWAI) that allowed an external assistant (e. g., the parent of the user) to immediately adjust the parameters of the prosthetic hand controller. In the PWAI, the myoelectric potential of use of the upper limb was plotted on an external terminal in real time. Simultaneously, the assistant adjusted the parameters of the prosthetic hand control device and manually manipulated the prosthetic hand. With these functions, children that have difficulty verbally communicating could obtain properly adjusted prosthetic hands. In addition, non-experts could easily adjust and manually manipulate the prosthesis; therefore, training for the prosthetic hands could be performed at home. Two types of hand motion discrimination methods were constructed in this study of the myoelectric control system: (1) a threshold control based on the myoelectric potential amplitude information and (2) a pattern recognition of the frequency domain features. In an evaluation test of the prosthesis threshold control system, child subjects achieved discrimination rates as high as 89%, compared with 96% achieved by adult subjects. Furthermore, the high discrimination rate was maintained by sequentially updating the threshold value. In addition, a discrimination rate of 82% on average was obtained by recognizing three motions using the pattern recognition method.

Congenital limb deficiency in Japan: a cross-sectional nationwide survey on its epidemiology.

BACKGROUND: Congenital limb deficiency is a rare and intractable disease, which impairs both function and appearance of the limbs. To establish adequate medical care, it is necessary to reveal the actual conditions and problems associated with this disease. However, there have been no extensive epidemiological surveys in Japan addressing this disease. This is the first nationwide epidemiological survey of congenital limb deficiency in this country. METHODS: With the cooperation of epidemiology experts, we performed a two-stage nationwide survey to estimate the number of patients with congenital limb deficiency and reveal basic patient features. We targeted orthopaedic surgery, paediatric, and plastic surgery departments. Hospitals were categorized according to the institution type and the number of hospital beds; hospitals were randomly selected from these categories. We selected 2283 departments from a total 7825 departments throughout Japan. In this study, we defined congenital limb deficiency as partial or total absence of the limbs, proximal to the proximal interphalangeal joint of the fingers/lesser toes or interphalangeal joint of the thumb/great toe. We distributed the first survey querying the number of initial patient visits from January 2014 to December 2015. Targets of the second survey were departments that reported one or more initial patient visits in the first survey. RESULTS: In the first survey, 1767 departments responded (response rate: 77.4%). Among them, 161 departments reported one or more initial patient visits. We conducted the second survey among these 161 departments, of which 96 departments responded (response rate: 59.6%). The estimated number of initial visits by patients with congenital limb deficiency was 417 (95% confidence interval: 339-495) per year in 2014 and 2015. The estimated prevalence of congenital limb deficiency in Japan was 4.15 (95% confidence interval: 3.37-4.93) per 10,000 live births. The sex ratio was 1.40. Upper limbs were more affected than lower limbs. CONCLUSIONS: We revealed the estimated number of initial patient visits per year and birth prevalence of congenital limb deficiency in Japan. Our results will contribute to establishing the disease concept and grades of severity of congenital limb deficiency.

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.