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.

Does timing influence rehabilitation outcomes in arthroscopic rotator cuff repair with biceps rerouting? a prospective randomized study.

BACKGROUND: Arthroscopic rotator cuff repair with biceps rerouting (ABR) has emerged as a reliable option for treating large posterosuperior rotator cuff tears (RCTs). This study aims to compare functional and structural outcomes of early vs. delayed motion rehabilitation protocols following ABR. METHODS: A total of 101 patients with semirigid, large, posterosuperior RCTs undergoing ABR were randomized into 2 groups: group I (early motion) with 53 patients (34 females, 19 males) and group II (delayed motion) with 48 patients (31 females, 17 males). In group I, the mean age was 63.9 years (range, 46-79), and in group II, it was 65.4 years (range, 43-78). The mean follow-up periods for group I and group II were 16.2 and 15.5 months, respectively. Preoperative and postoperative assessments were conducted at 3, 6, and 12 months, with structural integrity assessed with magnetic resonance imaging at a minimum follow-up of 12 months. Statistical analyses were performed to compare outcomes between the 2 groups. RESULTS: Both groups demonstrated significant improvements in visual analog scale score (group I: 4.0-1.6, group II: 3.7-1.4, P = .501), University of California-Los Angeles shoulder score (group I: 21.5-31.4, group II: 22.4-30.6, P = .331), and acromiohumeral interval (group I: 8.2 mm-9.1 mm, group II: 8.6 mm-9.5 mm, P = .412), with no statistically or clinically meaningful differences. Active range of movements (ROM) were not significantly different between groups, except for active forward flexion at 3 months (group I: 140.1°, group II: 119.2°, P = .006), that was not shown to be translated clinically into differences in function or healing between the groups in this study. Notably, retear rates were similar between groups (group I: 22.6%, group II: 20.8%, P = .826). CONCLUSION: This study's findings reveal no clinically discernible differences in active range of motion at 1-year follow-up between patients who underwent ABR for semirigid, large, posterosuperior RCTs and were assigned to either early or delayed motion protocols. Notably, the early motion group demonstrated a plateau in maximum range of movement improvement as early as 3 months postsurgery. Based on these results, implementing an early motion protocol is recommended as an effective approach in the postoperative rehabilitation following ABR.

The Arthroscopic Biceps Rerouting Technique Shows Better Early Clinical Outcomes within 1 Year Than Partial Repair in Large to Massive Rotator Cuff Tears.

Background and Objectives: The arthroscopic biceps rerouting (BR) technique was introduced as a novel technique for large-to-massive rotator cuff tears (LMRCTs). This method can restore shoulder stability, and its biomechanical effect was verified in a cadaver experiment. Recent reports have shown favorable clinical outcomes. This study aimed to compare the clinical outcomes of partial repair with those of the BR technique in LMRCTs. Materials and Methods: We included 72 patients who had undergone LMRCTs. Arthroscopic partial repair was performed in 31 patients (group I), while repair with the BR technique was performed in 41 patients (group II). Functional and imaging outcomes were evaluated and compared using a visual analog scale for pain, range of motion (ROM), American Shoulder and Elbow Surgeons (ASES) score, Constant score, and Korean Shoulder Score (KSS) before the surgery and at 3, 6, and 12 months after the surgery and at the last follow-up. Tendon integrity was investigated using magnetic resonance in all the patients at 12 months postoperative. Results: The mean follow-up period was 22.11 ± 10.47 months (range, 12-53 months). Forward flexion (p = 0.02) and external rotation at the side (p = 0.04) were significantly higher in group II than in group I on postoperative day (POD) 12 months. For internal rotation, group II showed significant improvement compared to group I on POD 3 months (p = 0.002) and at 6 months postoperative (p = 0.01). On POD 12 months, the ASES (p = 0.047) and KSS (p = 0.048) were better in group II. Significant improvements in pain and clinical scores were observed in both groups at the last follow-up. However, the two groups had no significant differences in pain, clinical scores, or ROM at the last follow-up. Retear of the repaired tendon was observed in nine patients in group I (29.03%) and eight in group II (19.51%, p = 0.35). Conclusions: Partial repair and repair using the BR technique effectively improved clinical and radiologic outcomes. The BR technique revealed early recovery of ROM and better clinical results than partial repair at one year postoperative. This could be a useful method in treating LMRCTs.

Long-Term Outcomes of Biceps Rerouting for Flexible Supination Contractures in Children With Brachial Plexus Birth Injuries.

PURPOSE: Forearm supination contractures occur in 7% of children with brachial plexus birth injuries (BPBI). Biceps rerouting is proposed when pronation has deteriorated but is passively correctable to at least 0° (neutral). The purpose of this investigation was to evaluate long-term outcomes of biceps rerouting for this indication, including magnitude and maintenance of correction, complications, and subsequent osteotomy. METHODS: We conducted a retrospective review of all children with BPBI and forearm supination contractures treated with biceps rerouting alone, for the above indications, from 1993 to 2017 with at least 2 years follow-up. Demographic information, BPBI characteristics, surgical details, and ranges of motion were obtained from medical records. Pre- and postoperative active pronation (AP) and supination (AS), elbow flexion contracture, and arc of forearm rotation (Arc) were analyzed using linear mixed-effect models. RESULTS: Twenty-five children (13 females; 13 left forearms; 15 global BPBI) underwent biceps rerouting at age 7 ± 3 years and were followed for 6 ± 3 years. Before surgery, the mean AP and AS were 6° ± 29° and 62° ± 27°, respectively. At the final follow-up, the mean AP, AS, and Arc were 39° ± 36°, 18° ± 34°, and 57° ± 42°, respectively. AP was significantly improved and AS was significantly decreased by 2 years after surgery and at the final follow-up. Neither Arc nor elbow flexion contracture changed significantly. Two of 25 (8%) children underwent subsequent forearm osteotomy. CONCLUSIONS: Biceps rerouting in children with BPBI improves the forearm position when pronation is deteriorating by shifting the arc from supination to pronation without decreasing the arc of motion or worsening elbow flexion contractures. There is a low risk of complications and a limited need for subsequent forearm osteotomy. These results are maintained over time. When performed before passive pronation is reduced beyond neutral, this procedure may prevent severe supination contractures and reduce the need for forearm osteotomy. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Effect of biceps rerouting technique to restore glenohumeral joint stability for large irreparable rotator cuff tears: a cadaveric biomechanical study.

BACKGROUND: The concept of stabilizing the humerus has taken on an important role in the treatment of irreparable cuff tears, and the biceps rerouting (BR) method is considered one of the most effective treatments in this field. The study aimed to evaluate the biomechanical effects of BR for large irreparable rotator cuff tears (LICTs). METHODS: A total of 8 cadaveric shoulders were used for testing under 5 conditions: intact shoulder, LICT, partial repair (PR), BR, and biceps rerouting with side-to-side repair (BRSS). Total rotational range of motion was measured at 40°, then 20°, and finally 0° of glenohumeral (GH) abduction. Superior humeral translation and subacromial contact pressure were measured at 0°, 30°, 60°, and 90° of external rotation at each abduction angle. Repeated-measures analyses of variance with Tukey post hoc tests were used for statistical comparisons. RESULTS: Superior humeral translation was significantly decreased in the BR and BRSS conditions compared with the LICT and PR conditions at 0° and 20° of GH abduction (P < .001). BR and BRSS significantly reduced subacromial contact pressure compared with LICT and PR at 0° of GH abduction (P < .001). There was no significant decrease in total rotational range of motion after BR at any abduction angle. CONCLUSION: BR biomechanically restored shoulder stability without overconstraining range of motion in an LICT model.

Evaluation of Extensor Pollicis Brevis as a Recipient of Tendon Transfer for Thumb Extension.

Introduction Rerouting of the extensor pollicis longus (EPL) is the standard part of tendon transfer surgery for thumb extension. It is done to overcome the ulnar vector of the EPL action. Extensor pollicis brevis (EPB), however, produces better thumb abduction and extension by virtue of its radial vector. The described anatomical variation of EPB extending the thumb interphalangeal joint (IPJ), therefore, gives the "best combination" of movements by a single-thumb extensor tendon. Materials and Methods We performed this transfer in six patients in whom the EPB was found to be extending the IPJ while checked intraoperatively. Three of these six patients were cases of radial nerve palsy and the other three presented with brachial plexus palsy. The outcome was assessed by measuring palmar and radial abduction of the thumb, Kapandji's score, and Bincaz's scale. Results We found satisfactory results in all the six patients. In our series, patients had an average radial extension of the thumb of 29.2 degrees and an average palmar abduction of the thumb of 65.7 degrees. On evaluation with the Bincaz score; one patient had excellent result, three patients had good results, and two patients had fair results. Conclusion In situations where EPL rerouting is not possible (as in cases where the donor tendon needs to reach the thumb from the ulnar side, for example, flexor carpi ulnaris), transfer to the EPB, provided it is extending the thumb IPJ, would produce better extension and abduction of the thumb than the transfer to the EPL.

Lumbar to sacral root rerouting to restore bladder function in a feline spinal cord injury model: Urodynamic and retrograde nerve tracing results from a pilot study.

AIMS: Lumbar to sacral rerouting surgery can potentially allow voiding via a skin-central nervous system-bladder reflex pathway. Here, we assessed if this surgery was effective in treating neurogenic bladder dysfunction/sphincter in felines. METHODS: Eight cats underwent spinal cord transection (SCT) at thoracic level 10/11. Unilateral L7 to S1 ventral root anastomosis was performed 1 month later in six cats. Two cats served as transection-only controls. Electrical and manual stimulation of L6-S1 dermatomes, and urodynamics were performed at 3, 5, 7, and 9/10 months post transection. At 9/10 months, cats were also evaluated by direct electrophysiological testing of anastomosed roots with urodynamics, then tissue collection and examination of the root anastomosis site and lumbosacral cord ventral horns for cells retrogradely labeled from tracer dye injected 2 weeks earlier into the bladder wall. RESULTS: At 9/10 months, four of six rerouted cats exhibited increased detrusor pressure provoked by cutaneous stimulation, one cat bilaterally. Two cats presented with a voiding stream after ipsilateral cutaneous stimulation at 7 and 9 months. All six rerouted animals showed regrowth of axons from the L7 ventral horn to the bladder, although some aberrant axonal regrowth was also observed. CONCLUSION: L7 to S1 ventral root rerouting below the level of SCT showed successful axonal regrowth to the bladder from the L7 spinal cord segment in all rerouted animals, and induced increased detrusor pressure response to cutaneous stimulation in a subset. This feasibility study paves the way for future animal studies for bladder reinnervation.

Production of Industrial Chemicals from CO2 by Engineering Cyanobacteria.

As photosynthetic prokaryotes, cyanobacteria can directly convert CO2 to organic compounds and grow rapidly using sunlight as the sole source of energy. The direct biosynthesis of chemicals from CO2 and sunlight in cyanobacteria is therefore theoretically more attractive than using glucose as carbon source in heterotrophic bacteria. To date, more than 20 different target chemicals have been synthesized from CO2 in cyanobacteria. However, the yield and productivity of the constructed strains is about 100-fold lower than what can be obtained using heterotrophic bacteria, and only a few products reached the gram level. The main bottleneck in optimizing cyanobacterial cell factories is the relative complexity of the metabolism of photoautotrophic bacteria. In heterotrophic bacteria, energy metabolism is integrated with the carbon metabolism, so that glucose can provide both energy and carbon for the synthesis of target chemicals. By contrast, the energy and carbon metabolism of cyanobacteria are separated. First, solar energy is converted into chemical energy and reducing power via the light reactions of photosynthesis. Subsequently, CO2 is reduced to organic compounds using this chemical energy and reducing power. Finally, the reduced CO2 provides the carbon source and chemical energy for the synthesis of target chemicals and cell growth. Consequently, the unique nature of the cyanobacterial energy and carbon metabolism determines the specific metabolic engineering strategies required for these organisms. In this chapter, we will describe the specific characteristics of cyanobacteria regarding their metabolism of carbon and energy, summarize and analyze the specific strategies for the production of chemicals in cyanobacteria, and propose metabolic engineering strategies which may be most suitable for cyanobacteria.

Modified Extensor Pollicis Longus Rerouting Technique for Boutonniere Deformity of the Thumb in Rheumatoid Arthritis.

PURPOSE: To assess the outcomes of a modified extensor pollicis longus (EPL) rerouting technique for boutonniere deformity of the thumb in patients with rheumatoid arthritis. METHODS: A total of 21 thumbs in 18 patients with a mean age of 63 years were retrospectively analyzed after an average follow-up period of 3.2 years. The preoperative deformities were classified as either mild (5 thumbs) or moderate (16 thumbs). After either metacarpophalangeal (MCP) joint synovectomy or implant arthroplasty, the ulnarly dislocated EPL tendon was reduced dorsally and sutured to the dorsal base of the proximal phalanx. If the interphalangeal (IP) joint extended with manual traction on the proximal portion of the extensor pollicis brevis tendon, no further treatment was considered. If the IP joint did not extend with this maneuver, the insertion of the extensor pollicis brevis tendon was dissected and transferred to the distal portion of the EPL tendon. RESULTS: The average MCP joint extensor lag improved from 62° (range, 32° to 85°) before surgery to 17° (range, active extension 12° to extensor lag 70°) at the final follow-up (P < .05), whereas average MCP joint flexion decreased from 83° (range, 52° to 95°) to 68° (range, 30° to 90°) (P < .05). Hyperextension at the IP joint was improved from 30° (range, 10° to 50°) before surgery to an average extensor lag of 2° (range, extensor lag 24° to hyperextension 20°) at the final follow-up. The average combined MCP and IP motion did not significantly change. The boutonniere deformity was improved in 18 of 21 thumbs. The 3 failures all had moderate-stage deformity prior to treatment. CONCLUSIONS: A modified EPL rerouting technique provided satisfactory results together with a low risk of IP joint extension loss. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Technique of Pronator Teres Rerouting in Pediatric Patients With Spastic Hemiparesis.

Children with spastic hemiparesis can present with forearm pronation deformities that can greatly impair function. In the appropriate setting, pronator teres rerouting can provide active supination while preserving active pronation, which may improve function in these patients. Patient selection is imperative for the success of this procedure because, in the wrong setting, pronator teres rerouting can lead to fixed supination deformity that may actually worsen position and function in these patients.

An Improved Simulated Annealing Technique for Enhanced Mobility in Smart Cities.

Vehicular traffic congestion is a significant problem that arises in many cities. This is due to the increasing number of vehicles that are driving on city roads of limited capacity. The vehicular congestion significantly impacts travel distance, travel time, fuel consumption and air pollution. Avoidance of traffic congestion and providing drivers with optimal paths are not trivial tasks. The key contribution of this work consists of the developed approach for dynamic calculation of optimal traffic routes. Two attributes (the average travel speed of the traffic and the roads' length) are utilized by the proposed method to find the optimal paths. The average travel speed values can be obtained from the sensors deployed in smart cities and communicated to vehicles via the Internet of Vehicles and roadside communication units. The performance of the proposed algorithm is compared to three other algorithms: the simulated annealing weighted sum, the simulated annealing technique for order preference by similarity to the ideal solution and the Dijkstra algorithm. The weighted sum and technique for order preference by similarity to the ideal solution methods are used to formulate different attributes in the simulated annealing cost function. According to the Sheffield scenario, simulation results show that the improved simulated annealing technique for order preference by similarity to the ideal solution method improves the traffic performance in the presence of congestion by an overall average of 19.22% in terms of travel time, fuel consumption and CO2 emissions as compared to other algorithms; also, similar performance patterns were achieved for the Birmingham test scenario.

Treatment of supination deformity for obstetric brachial plexus injury: a systematic review and meta-analysis.

PURPOSE: To conduct a systematic review and meta-analysis of the literature evaluating treatment outcome for supination deformity in obstetric brachial plexus injury. METHODS: We included studies on brachial plexus and supination deformity with follow-up of at least one year and quantitative measurements of forearm mean passive pronation and position at rest. Meta-analysis was used to explore modifying factors. RESULTS: An elaborate search strategy resulted in 366 studies, of which 13 were included totaling 238 patients (157 osteotomies and 71 biceps rerouting). There was a 75° gain in position at rest and a 65° gain in passive pronation for the osteotomy group, compared to a 79° gain in position at rest for the biceps rerouting group. More severe deformities had greater gains. No influence of age was found. Important adverse effects were hardware failure and a biceps rupture. Recurrence in the osteotomy group was 20% to 40%, versus none in the soft-tissue group. CONCLUSIONS: This review showed an overall benefit for forearm osteotomies and for biceps rerouting for supination deformity with the gain proportionate to the severity of the deformity. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic III.

Changing vessel routes could significantly reduce the cost of future offshore wind projects.

With the recent emphasis on offshore wind energy Coastal and Marine Spatial Planning (CMSP) has become one of the main frameworks used to plan and manage the increasingly complex web of ocean and coastal uses. As wind development becomes more prevalent, existing users of the ocean space, such as commercial shippers, will be compelled to share their historically open-access waters with these projects. Here, we demonstrate the utility of using cost-effectiveness analysis (CEA) to support siting decisions within a CMSP framework. In this study, we assume that large-scale offshore wind development will take place in the US Mid-Atlantic within the next decades. We then evaluate whether building projects nearshore or far from shore would be more cost-effective. Building projects nearshore is assumed to require rerouting of the commercial vessel traffic traveling between the US Mid-Atlantic ports by an average of 18.5 km per trip. We focus on less than 1500 transits by large deep-draft vessels. We estimate that over 29 years of the study, commercial shippers would incur an additional $0.2 billion (in 2012$) in direct and indirect costs. Building wind projects closer to shore where vessels used to transit would generate approximately $13.4 billion (in 2012$) in savings. Considering the large cost savings, modifying areas where vessels transit needs to be included in the portfolio of policies used to support the growth of the offshore wind industry in the US.

Isopropanol production using engineered Corynebacterium glutamicum from waste rice straw biomass.

Isopropanol, a well-known biofuel, is a widely used precursor for chemical products that can replace nonrenewable petroleum energy. Here, engineered Corynebacterium glutamicum that can effectively utilize all xylose and glucose in agricultural waste rice straw to produce isopropanol was described. First, codon mutations were introduced into transporters and glycolytic-related genes to decrease the glucose preference of C. glutamicum. A more energetically favorable xylose oxidative pathway was constructed that replaced traditional xylose isomerization pathways, saving twice the number of enzymatic steps. A succinate auxiliary module was incorporated into the tricarboxylic acid cycle (TCA), connecting the xylose-utilized pathway with the isopropanol pathway to maximize xylose orientation towards the product. The final engineered strain successfully consumed 100 % of the xylose from NaOH-pretreated, enzyme-hydrolyzed rice straw and effectively synthesized 4.91 g/L isopropanol. This study showcases the successful conversion of agricultural waste into renewable energy, unveiling new possibilities for advancing biological fermentation technology.

Evolution of pyruvate kinase-deficient Escherichia coli mutants enables glycerol-based cell growth and succinate production.

AIMS: The aim of this study was to engineer Escherichia coli strains that efficiently produce succinate from glycerol under anaerobic conditions after an aerobic growth phase. METHODS AND RESULTS: We constructed E. coli strain ss195 with deletions of pykA and pykF, which resulted in slow growth on glycerol as sole carbon source. This growth defect was overcome by the selection of fast-growing mutants. Whole-genome resequencing of the evolved mutant ss251 identified the mutation A595S in PEP carboxylase (Ppc). Reverse metabolic engineering by introducing the wild-type allele revealed that this mutation is crucial for the described phenotype. Strain ss251 and derivatives thereof produced succinate with high yields above 80% mol mol(-1) from glycerol under nongrowth conditions. CONCLUSIONS: The results show that during the aerobic growth of ss251, the formation of pyruvate proceeds via the proposed POMP pathway, starting with the carboxylation of PEP by Ppc. The resulting oxaloacetate is reduced by malate dehydrogenase (Mdh) to malate, which is then decarboxylated back to pyruvate by a malic enzyme (MaeA or MaeB). Mutation of ppc is crucial for fast growth of pykAF mutants on glycerol. SIGNIFICANCE AND IMPACT OF STUDY: An E. coli mutant that is capable of achieving high yields of succinate (a top valued-added chemical) from glycerol (an abundant carbon source) was constructed. The identified ppc mutation could be applied to other production strains that require strong PEP carboxylation fluxes.

Rerouting of follicle-stimulating hormone secretion and gonadal function.

Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are synthesized in the same pituitary cell, i.e., gonadotrope. They both consist of a common α-subunit that is noncovalently assembled with a hormone-specific ß-subunit in gonadotropes. The heterodimers exit gonadotropes through distinct modes of trafficking and secretion. The FSH is constitutively secreted, whereas LH is secreted in pulses through the regulated pathway that involves dense core granules. Based on several in vitro mutagenesis studies, the carboxy terminus heptapeptide of human LH-ß subunit is identified as a gonadotrope sorting determinant. When heptapeptide is genetically fused to human FSH-ß subunit and the mutant transgene expressed on a Fshb null genetic background, the rerouted FSH mutant dimer enters the LH secretory pathway, stored in dense core granules, coreleased with LH on gonadotropin releasing hormone stimulation and rescues Fshb null mice as efficiently as the constitutively secreted wild-type FSH. The rerouted FSH markedly suppresses follicle atresia and significantly enhances ovulations per cycle and prolongs the female reproductive life span. Gonadotropin rerouting is emerging as a novel paradigm to treat ovarian dysfunction in women, and may explain the origins of ovarian cyclicity as well as provide clues to understand gene and protein networks that maintain optimal ovarian function throughout the female reproductive life span.

Jugulotympanic Paraganglioma With Preoperative Embolization That Led to Facial Nerve Paralysis and Surgical Rerouting of the Nerve.

Paragangliomas are mostly benign, slow-growing, hypervascular tumors originating from neural crest derivatives. Head and neck (H&N) paragangliomas represent <1% of all H&N tumors and <5% are malignant. They are mostly non-secreting tumors that originate from autonomous parasympathetic paraganglia. We present a case of right middle ear jugulotympanic paraganglioma, a subtype of H&N paragangliomas, which had been misdiagnosed as otosclerosis for about 10 years. The patient was suffering from worsening tinnitus along with hearing impairment. High clinical suspicion of jugular paraganglioma prevented us from taking a biopsy. Complete surgical excision after preoperative embolization was decided. Embolization resulted in facial nerve paralysis, however, facial nerve rerouting was performed during the complete surgical excision of the tumor. The patient remains disease-free three years postoperatively, with House-Brackmann III facial nerve paralysis.

Tibialis anterior rerouting combined with calcaneal lengthening osteotomy as a single-stage reconstruction of symptomatic flexible flatfoot in children and adolescents.

BACKGROUND: Symptomatic flexible flatfoot in children and adolescents should be surgically managed only if conservative measures have failed. The aim of this study was to assess functional and radiological results of tibialis anterior rerouting combined with calcaneal lengthening osteotomy as s single-stage reconstruction of symptomatic flexible flatfoot. METHODS: The current study was a prospective study of patients with symptomatic flexible flatfoot treated by single-stage reconstruction in the form of tibialis anterior tendon rerouting combined with calcaneal lengthening osteotomy. The American Orthopaedic Foot and Ankle Society score (AOFAS) was utilized to evaluate the functional outcomes. The evaluated radiological parameters included the standing anteroposterior (AP) and lateral talo-first metatarsal angle, talar head coverage angle, and calcaneal pitch angle. RESULTS:  The current study included 16 patients (28 feet) with a mean age of 11.6 ± 2.1 years. There was a statistically significant improvement in the mean AOFAS score from 51.6 ± 5.5 preoperatively to 85.3 ± 10.2 at final follow-up. Postoperatively, there was a statistically significant reduction in the mean AP talar head coverage angle from 13.6 ± 4.4° to 3.9 ± 3°, the mean AP talo-first metatarsal angle from 16.9 ± 4.4° to 4.5 ± 3.6°, and the mean lateral talo-first metatarsal angle from 19.2 ± 4.9° to 4.6 ± 3.2°, P < 0.001. Additionally, the mean calcaneal pitch angle increased significantly from 9.6 ± 1.9° to 23.8 ± 4.8°, P < 0.001. Superficial wound infection occurred in three feet and was treated adequately by dressing and antibiotics. CONCLUSION:  Symptomatic flexible flatfoot in children and adolescents can be treated with combined lateral column lengthening and tibialis anterior rerouting with satisfactory radiological and clinical outcomes. Level of evidence Level IV.

Management of Pelvic Fracture Urethral Injury: Is Supracrural Urethral Rerouting (Step 4) Becoming Anecdotical or Does It Remain in Force?

Webster described a step-based perineal approach for repairing the posterior urethra in patients with pelvic fracture urethral injury (PFUI). The higher the complexity of the step, the higher the morbidity for the patient and the lower the surgical outcomes. We evaluated the outcomes of anastomotic urethroplasty (especially Step 4 or higher) or substitution urethroplasty in patients with PFUI at our center. Between 2013 to 2021, we retrospectively collected data on patients with PFUI. Surgical procedures were categorized according to the Webster classification and rates of each step were reported. The success rate was defined as Qmax above 10 mL/s and no need for further treatment. In this period, 737 male patients with PFUI were surgically treated. Notably, 18.8%, 17.6%, 46%, 1.8%, and 5.6% of included patients received steps 1, 2, 3, and 4 and the abdominoperineal approach, respectively. In 68 (9.2%) patients, the substitution of urethroplasty with a pedicled preputial tube (PPT) was needed. The success rate was 69.2% in Step 4, 74.4% in the abdominoperineal approach, and 86.4% in PPT; however, recurrence-free survival was not significantly different between groups (p = 0.22). Step 4 perineal anastomotic urethroplasty represents a surgical option in the armamentarium of PFUI treatment. Indications should be carefully reviewed to improve patient selection and avoid surgical failure, stopping at the step which first gives a tension-free anastomosis.

The Biomechanical and Histological Processes of Rerouting Biceps to Treat Chronic Irreparable Rotator Cuff Tears in a Rabbit Model.

BACKGROUND: Recently, the biceps was rerouted into a newly fabricated bicipital groove for in situ superior capsular reconstruction (SCR), resulting in promising time-zero cadaveric and clinical outcomes. However, no studies have determined the in vivo biomechanical and histological processes after the biceps is transposed to a nonanatomic position. PURPOSE: To explore the in vivo biomechanical and histological processes of the rerouting biceps tendon to treat chronic irreparable rotator cuff tears (IRCTs) in a rabbit model. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 94 skeletally mature male rabbits were used to create a chronic IRCT model in the supraspinatus tendon. Then, the biceps rerouting procedures were performed in rabbits with chronic IRCT. Eighteen rabbits were sacrificed at 1, 3, 6, 9, and 12 weeks postoperatively for biomechanical testing, micro-computed tomography scanning, and histological analysis. The biomechanical and histological changes of intra- and extra-articular portions of the rerouting biceps were evaluated at each time point, with the contralateral native superior capsule (NSC) and the native biceps (NB) as controls, respectively. The morphology and bone formation of the fabricated bicipital grooves were evaluated, with native grooves as controls. RESULTS: The intra-articular rerouting biceps tendon was progressively remodeled over time, displaying denser fibers and more mature collagen than those of the NSC, with gradual improvements in the tendon-to-bone healing interface from 6 to 12 weeks. Consequently, the failure load and stiffness of the intra-articular rerouting biceps portion increased with time and were significantly higher than those of the NSC from 9 weeks. Similarly, the extra-articular portion of the rerouting biceps progressively healed into a new bicipital groove, as demonstrated by a smaller tendon-to-bone interface from 6 to 12 weeks, resulting in greater failure load and stiffness at 9 and 12 weeks than those of the NB attachment. The newly fabricated bicipital groove showed similar morphology to that of the native groove with sufficient trabecular bone formed underneath. CONCLUSION: The rerouting biceps could progressively remodel and heal into the newly fabricated bicipital groove over time, resulting in greater biomechanical performances in intra- and extra-articular portions than the NSC and the NB attachment. CLINICAL RELEVANCE: The biceps rerouting technique may be a feasible procedure to perform in situ SCR to treat IRCT in the future clinical practice; however, more clinical evidence is required.