Factors Affecting Postoperative Courses After Removal of Transphyseal Screws Inserted for Correction of Genu Valgum.

BACKGROUND: The aim of this study was to investigate factors determining the final outcomes of hemipercutaneous epiphysiodesis using transphyseal screw (PETS) for the genu valgum, especially focusing on postoperative courses after screw removal. METHODS: Fifty-five patients with idiopathic genu valgum treated with hemi-PETS were included. The mechanical lateral distal femoral angle (mLDFA) and medial proximal tibial angle (MPTA) were measured to calculate the degree of correction and rebound. Regarding factors related to surgical techniques, the number of screw threads beyond the physis, the moment arm of the screw, and screw insertion angles were measured. RESULTS: In 54 femoral segments (randomly selected in bilateral cases), hemi-PETS was performed with a growth remaining of 2.0±0.6 years. The screw was removed after 6.5±2.1 months, and the degree of correction was 5.0±1.5 degrees. The mean rebound angle was -0.4±2.4 (the negative value means further correction after screw removal). A late time of surgery and an extreme peripheral position of a screw were associated with the growth inhibition. In 50 tibial segments (also randomly selected in bilateral cases), a screw was inserted with a growth remaining of 2.0±0.6 years and removed after 6.3±1.9 months. The degree of correction was 2.9±1.7 degrees during the interval, and the rebound angle was 0.8±1.7 degrees. An earlier time of surgery and a greater correction angle before screw removal were associated with the rebound phenomenon. CONCLUSIONS: Growth inhibition of >1.6 degrees was observed in about one-fourth of femoral segments. An extreme peripheral position of a screw should be avoided when performing hemi-PETS at the distal femur. We also recommend not performing hemi-PETS at distal femur with too short a period of growth remaining. LEVEL OF EVIDENCE: Level III-retrospective comparative series.

Serial Change in Patellar Height after Tension Band Wiring of Patellar Fractures.

Background and Objectives: Patella baja is a common complication after operative treatment for patellar fracture. This study aimed to investigate (1) the serial changes in patellar height and (2) the potential predictive factors for patellar height changes after tension band wiring (TBW) for patellar fractures. Materials and Methods: Forty-one patients who underwent TBW for patellar fracture between March 2019 and September 2022 were enrolled. To identify serial changes in patellar height, modified Blackburne-Peel index (mBPI) was assessed at just after surgery, at 3 months, at 6 months, at 1 year and at the final follow-up. Multiple regression analysis was conducted to identify factors correlated with mBPI difference between the contralateral side (considered as preoperative status) and injured side. Results: The postoperative mBPI exhibited a decline over time (mean mBPI immediately post operation/3 months/6 months/1 year/final follow-up: 0.69/0.63/0.63/0.62/0.61) Specifically, mBPI showed a significant reduction immediately post operation to 3 months (p < 0.001), although comparisons at other time points did not reveal significant differences. A lower position of the fracture was associated with a decrease in patellar height after surgery. Conclusions: Patellar height was mainly decreased from immediately post operation to 3 months. A fracture in a lower position of associated with decreased patellar height after the TBW of the transverse patellar fracture.

Factors Affecting Rebound Phenomenon After Temporary Hemiepiphysiodesis and Implant Removal for Idiopathic Genu Valgum in Adolescent Patients.

BACKGROUND: The aim of this study was to investigate factors determining postoperative courses, especially focusing on the rebound phenomenon, in adolescent patients with idiopathic genu valgum who underwent temporary hemiepiphysiodesis and implant removal. METHODS: We identified and reviewed patients with idiopathic genu valgum treated with temporary hemiepiphysiodesis [using tension-band plates (plate group, PG) or transphyseal screws (screw group, SG)] and followed-up to skeletal maturity. RESULTS: In our cohort [68 patients and their 68 limbs (randomly selected in bilateral cases)], the mean hip-knee-ankle alignment was -5.4±1.8 degrees at the time of temporary hemiepiphysiodesis (negative means valgus), 2.6±2.1 degrees at the time of implant removal, and 0.7±2.6 degrees at the last follow-up, respectively. Regarding the implants, the correction speed was not significantly different (P=0.192-0.315) between the PG (total 1.29±0.37 degrees/mo, 0.71±0.23 degrees/mo at distal femur, 0.59±0.16 degrees/mo at proximal tibia, n=19) and the SG (total 1.22±0.49 degrees/mo, 0.65±0.25 degrees/mo at distal femur, 0.57±0.23 degrees/mo at proximal tibia, n=49). The magnitude of rebound phenomenon in the PG (4.1±1.9 degrees) was greater (P<0.001) than that in the SG (1.1±3.1 degrees). The use of plates and faster correction speed, rather than more severe preoperative deformity or greater correction angle, were positively associated with the rebound phenomenon in regression analyses. Among the 68 knees, 1 showed valgus alignment ≥5 degrees and 5 showed varus alignment ≥5 degrees at the last follow-up. All the 6 cases were observed in the SG. Surgical wound dehiscence was observed in 1 patient in the PG. CONCLUSIONS: The use of plates and faster correction speed were positively associated with the rebound phenomenon. Careful attention will be needed with the corresponding conditions for optimal results. Progressive genu varum after transphyseal screw removal, which was observed in this study, should be explored in future research. LEVEL OF EVIDENCE: Level III-retrospective comparative series.

Predictors of ideal outcomes after reconstructive surgery for chronic Monteggia fracture in children.

BACKGROUND: We aimed to analyze surgical outcomes of reconstructive surgery for chronic Monteggia fracture, which is one of the most challenging problems for orthopaedic surgeons. METHODS: Twenty-eight patients were followed during 55.6 ± 32.0 months after open reduction of the radial head combined with ulnar osteotomy and annular ligament reconstruction. The mean interval from trauma was 15.1 ± 19.6 months, and the mean age at the surgery was 9.1 ± 3.5 years. In addition to the chronological age, elbow maturity was assessed using the Sauvegrain score. Surgical outcomes were primarily evaluated using the Kim's score. In addition, we newly defined more successful criteria for the ideal surgical outcomes, equivalent to preinjury status. RESULTS: There were 19 excellent, 3 good, 4 fair, and 2 poor outcomes based on the Kim's scoring system. Among the 19 patients with excellent outcomes, 14 met our criteria for the ideal outcomes. The age (p < 0.001) and the Sauvegrain score (p < 0.001) were lower, and the interval (p = 0.004) was shorter in 14 patients with ideal outcomes. There were 9 patients with preoperative deformation of the radial head, and all of them showed non-ideal outcomes. In regression analyses, lower Sauvegrain score (p = 0.004) and shorter interval (p = 0.012) were associated with higher postoperative Kim's score, and lower Sauvegrain score (p = 0.031) was related to the achievement of the ideal outcomes. With the Sauvegrain score of >21.5, all patients had postoperative re-dislocation or osteoarthritic changes regardless of the interval. With the Sauvegrain score of <21.5 and an interval of ≤7 months, the ideal outcomes were achieved in 85.7%, and no patients had postoperative re-dislocation or osteoarthritic changes. CONCLUSION: Over the skeletal ages of 14 years in boys and 11.5 years in girls, reconstructive surgery must be cautiously indicated. Under these skeletal ages with an interval of ≤7 months and undeformed radial head, it appears to be ideal. STUDY DESIGN: Level III, Retrospective comparative study.

Substance P, A Promising Therapeutic Target in Musculoskeletal Disorders.

A large number of studies have focused on the role of substance P (SP) and the neurokinin-1 receptor (NK1R) in the pathogenesis of a variety of medical conditions. This review provides an overview of the role of the SP-NK1R pathway in the pathogenesis of musculoskeletal disorders and the evidence for its role as a therapeutic target for these disorders, which are major public health problems in most countries. To summarize, the brief involvement of SP may affect tendon healing in an acute injury setting. SP combined with an adequate conjugate can be a regenerative therapeutic option in osteoarthritis. The NK1R antagonist is a promising agent for tendinopathy, rheumatoid arthritis, and osteoarthritis. Research on the SP-NK1R pathway will be helpful for developing novel drugs for osteoporosis.

Low serum vitamin B12 levels are associated with degenerative rotator cuff tear.

BACKGROUND: Vitamin B12 (Vit B12) deficiency results in elevated homocysteine levels and interference with collagen cross-linking, which may affect tendon integrity. The purpose of this study was to investigate whether serum Vit B12 levels were correlated with degenerative rotator cuff (RC) tear. METHODS: Eighty-seven consecutive patients with or without degenerative RC tear were enrolled as study participants. Possible risk factors (age, sex, medical history, bone mineral density, and serum chemistries including glucose, magnesium, calcium, phosphorus, zinc, homocysteine, Vitamin D, Vit B12, homocysteine, and folate) were assessed. Significant variables were selected based on the results of univariate analyses, and a logistic regression model (backward elimination) was constructed to predict the presence of degenerative RC tear. RESULTS: In the univariate analysis, the group of patients with degenerative RC tear had a mean concentration of 528.4 pg/mL Vit B12, which was significantly lower than the healthy control group (627.1 pg/mL). Logistic regression analysis using Vit B12 as an independent variable revealed that Vit B12 concentrations were significantly correlated with degenerative RC tear (p = 0.044). However, Vit B12 levels were not associated with tear size. CONCLUSION: Low serum levels of Vit B12 were independently related to degenerative RC tear. Further investigations are warranted to determine if Vit B12 supplementation can decrease the risk of this condition.

Ankle strength is not strongly associated with postural stability in patients awaiting surgery for chronic lateral ankle instability.

PURPOSE: (1) To describe ankle strength and postural stability in patients with chronic lateral ankle instability and (2) to analyse the correlation between deficits in ankle strength and postural stability. METHODS: Results of preoperative isokinetic and balance tests in 203 patients whose contralateral ankle was normal were retrospectively reviewed. Isokinetic peak torque values of eversion and inversion at 2 angular velocities (30°/s and 120°/s) were measured in the injured and normal ankles. In the balance test, the percent differences of 3 actual scores (overall, anterior-posterior, and medial-lateral) between the injured and normal ankles were calculated. Additional statistical analyses were performed to evaluate weakness of ankle strength, postural stability deficits, and their correlation. RESULTS: Significant differences in 4 peak torque values and 4 relative peak torque values (peak torque/body weight) were found between the injured and normal ankles. All 8 values were significantly lower in the injured ankles. Weakness was severe during inversion and at 30°/s. In the balance test, 49 subjects (24.1%) had significant deficits in postural stability and 109 (53.7%) had favourable results. No strong association was found between weakness of ankle strength and deficits in postural stability. CONCLUSIONS: Strength measurement alone is insufficient to evaluate preoperative functional deficits, and other functional tests are required to measure postural stability. The results of this study provide further evidence for a rehabilitation programme consisting of proprioceptive training as well as strengthening. The proprioceptive training must be an integral part of the rehabilitation programme in addition to strengthening exercise. LEVEL OF EVIDENCE: Case series, Level IV.

Repair of only anterior talofibular ligament resulted in similar outcomes to those of repair of both anterior talofibular and calcaneofibular ligaments.

PURPOSE: To compare the surgical outcomes of the two different ankle stabilization techniques. METHODS: This randomized controlled trial aimed to compare the outcomes of the modified Broström procedure with [calcaneofibular ligament (CFL) group] or without CFL repair [anterior talofibular ligament (ATFL) only group]. Of the 50 patients randomly assigned to two groups, 43 were followed up prospectively for ≥ 2 years (CFL group: 22 patients, 36.6 ± 13.1 months; ATFL Only group: 21 patients, 35.3 ± 11.9 months). Functional outcomes were assessed using the Karlsson-Peterson and Tegner activity level scoring systems. Anterior talar translation (ATT), talar tilt angle (TTA), and degrees of displacement of the calcaneus against the talus on stress radiographs were measured. All parameters were compared between the two groups. Multiple regression analysis setting the postoperative Karlsson-Peterson score as the dependent variable was performed to determine the significant variable. RESULTS: There were no significant differences between the two groups in functional (Karlsson-Peterson and Tegner activity level) scores at the last follow-up and their changes. There were no significant differences between the two groups in the ATT, TTA, their differences compared with the contralateral ankles, and degrees of displacement of the calcaneus against the talus at the last follow-up. Osteochondral lesion of the talus rather than CFL repair was the significant variable related to functional outcome. CONCLUSION: The modified Broström procedure with additional CFL repair did not result in a significant advantage in any measured outcome at 3 years. LEVEL OF EVIDENCE: Randomized controlled trial, Level I.

Difficulties During Ponseti Casting for the Treatment of Idiopathic Clubfoot.

The Ponseti method has resulted in excellent outcomes in the treatment of idiopathic clubfoot. To evaluate the process of serial casting, most studies previously used the number of casts required to achieve correction. In contrast, difficulties that occurred during serial casting were rarely studied. We reviewed 47 patients with severe idiopathic clubfoot (Dimeglio score ≥10) and a follow-up period of ≥4 years by focusing on difficulties during the Ponseti casting and their related factors. All events requiring temporary discontinuation and/or delay of scheduled casting were considered difficulties. Among the 47 patients, difficulties occurred in 18 patients (38.3%). Initial Dimeglio score (14.9 ± 2.5 [vs 13.5 ± 2.3, p = .042]), its subcomponent of equinus (3.8 ± 0.4 [vs 3.3 ± 0.6, p = .005]), and the number of casts (6.3 ± 2.0 [vs 4.9 ± 1.2, p = .009]) in the 18 patients with difficulties were greater than those of the remaining 29 patients. In addition, the foot length was shorter (7.2 ± 0.6 cm [vs 7.7 ± 0.8 cm, p = .030]) in patients with difficulties. In the regression analysis, both subcomponents of equinus and foot length showed the significance for the occurrence of difficulties. During 8.7 ± 3.8 years, further surgery was needed in 35 patients (74.5%) because of residual or recurrent deformity. The ratio was higher in patients with difficulties (94.4% [vs 62.1%, p = .017]). In our experience, difficulties frequently occurred in feet with rigid equinus and small length, and further surgery was required after the initial correction in almost all of the feet with difficulties.

Clinical and Radiographic Characteristics of Atypical Slipped Capital Femoral Epiphysis.

BACKGROUND: Slipped capital femoral epiphysis (SCFEs) can be idiopathic or atypical (associated with renal failure, radiation therapy, and endocrine disorders). It is important to estimate the likelihood that atypical SCFE shows different clinical and radiographic characteristics and complications with typical SCFEs. METHODS: We retrospectively reviewed 53 patients (66 hips) with SCFEs managed between 1995 and 2016. Sex, age, weight, height, the duration of symptoms the laterality of the slip, and complications were recorded. Bilateral hip and lower extremity long bone radiographs were utilized to record slip angle, genu valgus deformity. Statistical analyses were performed. RESULTS: Among 53 children (32 boys and 21 girls) with 66 SCFEs, 22 children had 29 atypical SCFEs, and 31 children had 38 typical SCFEs. The average age at the time of presentation for the initial SCFEs was 10.9±0.3 years. The average duration of symptoms was 14.1±21.8 weeks. The average Southwick slip angle difference was 23.3±14.8 degrees. There are 43 mild, 13 moderate, and 10 severe SCFEs. 58 were classified as stable, and 8 were unstable. There were significant differences in terms of average age (10.4±2.6 y for atypical SCFEs, 11.2±1.4 for typical SCFEs; P=0.036), average weight (36.2±22.3 kg for patients with atypical slips, compared with 56.9±9.9 kg for those with typical slips; P<0.001), height (132.1±17.6 cm for those with atypical slips, compared with 148.9±12.1 for those with typical slips; P<0.001), and the body mass index (19.4±5.6 kg/cm for those with atypical slips, compared with 25.8±4.6 for those with typical slips; P<0.001). In the group of 22 children with atypical slipped capital epiphysis, there were 19 children with neoplasm (8 neuroblastomas, 3 medulloblastomas, 3 retinoblastomas, 2 ependymomas, 1 craniopharyngioma, 1 Wilms tumor, 1 immature teratoma), 4 children with primary endocrine disorder. We categorized atypical SCFEs in 3 groups by etiology; endocrine disorder-associated (ENDA) SCFEs, chemotherapy-associated (CTA) SCFEs, and radiation therapy-associated (RTA) SCFEs. Subjects of RTA were included if exposed to pelvic irradiation or total body irradiation. There were 4 ENDA, 9 RTA, and 16 CTA. Atypical SCFEs had significantly more valgus slips (P<0.001) and genu valgus deformity (P<0.001) compared with in the group of typical slipped capital epiphysis. Among the group of atypical SCFEs, children with CTA had significantly low body weight, height, and body mass index. CONCLUSIONS: The markedly greater incidence of valgus displacement of proximal femoral epiphysis and genu valgum in childhood cancer survivors with pelvic irradiation and chemotherapy may be associated with atypical SCFE. The authors conclude that in pediatric cancer survivors with hip pain, consideration should be given to atypical SCFE with valgus slip and long-term follow-up of lower extremity alignment. LEVEL OF EVIDENCE: Level III-retrospective comparative study. See instructions for authors for a complete description of levels of evidence.

Surgical outcomes after excision of pigmented villonodular synovitis localized to the ankle and hindfoot without adjuvant therapy.

Although a benign disorder, pigmented villonodular synovitis (PVNS) has a high rate of recurrence. Because of the high incidence of recurrence and concern about destruction of the affected joint, several adjuvant therapies have been promoted without a clear standard treatment strategy. We reviewed cases of PVNS affecting the ankle and hindfoot joints (ankle and/or subtalar joints) treated with surgical resection without adjuvant therapy in an effort to identify the incidence of PVNS recurrence after excision without adjuvant therapy. Of the 10 cases with a mean follow-up duration of 33.2 ± 19.8 months, 4 (40%) developed a recurrence, with a mean interval of 6 (range 3 to 14) months. At the final follow-up visit, the mean American Orthopaedic Foot and Ankle Society ankle-hindfoot score was 86.6 ± 12. The clinical outcomes of PVNS affecting the ankle and hindfoot joints are associated with a relatively high incidence of recurrence, and additional clinical investigation comparing the incidence of recurrence in patients undergoing excision versus excision with adjuvant therapy is needed for us to better understand this condition and provide more informed recommendations to our patients.

Surgical outcome of desmoid tumors: adjuvant radiotherapy delayed the recurrence, but did not affect long-term outcomes.

BACKGROUND: We retrospectively reviewed the outcomes of desmoid tumor (DT) patients treated by surgical excision. METHODS: Among 155 consecutive patients, 119 patients satisfied our inclusion criteria. The mean follow-up duration was 82 months. Age, gender, location, size, depth, resection margin, adjuvant radiotherapy, and excision history were analyzed for the outcomes. RESULTS: The recurrence-free survival (RFS) rates were 75% at 5 years and 72% at 10 years. Twenty-seven (93.1%) out of 29 recurrences were detected within 5 years. In multivariate analysis, positive resection margin and excision history were independently associated with the RFS. In the comparison between the propensity score matched groups, adjuvant radiotherapy was not significantly associated with the RFS. The mean time interval from surgery to recurrence was 30.0 ± 28.7 months (median, 20 months; range, 4-123 months). This interval was significantly longer for patients who received adjuvant radiotherapy than for those who received surgical resection only, both in all recurrences and in recurrences in matched cases. CONCLUSIONS: Surgical excision appears to be a reliable treatment option for DTs. However, positive outcomes require a clear resection margin. Adjuvant radiotherapy may delay the recurrence of the tumor, although it seems to have no effect on the ultimate relapse rate.

The comparative efficacies of intra-articular and IV tranexamic acid for reducing blood loss during total knee arthroplasty.

PURPOSE: Reduction in blood loss during surgery stabilizes hemodynamic status and aids in recovery after total knee arthroplasty (TKA). In this study, the authors examined whether different administration routes of tranexamic acid (TNA) might affect the amount of blood loss after TKA. METHODS: A total of 150 patients were prospectively allocated to each of the three groups (intravenous, intra-articular, and placebo group) and underwent unilateral TKA. During closing the operative wound, TNA (1.5 g mixed in 100 cc of saline) was administered intravenously or intra-articularly according to the enrolled group, and an equivalent volume of normal saline was administered into the knee joint cavity and intravenously in the placebo group, respectively. The amount of blood loss and transfusion, and changes in haemoglobin levels were documented accordingly. RESULTS: The mean blood loss in the intravenous, intra-articular, and placebo groups were 528 ± 227, 426 ± 197, and 833 ± 412 ml, respectively. About 66 % (intravenous), 80 % (intra-articular), and 6 % (placebo) of each group did not require transfusion for any reason, and the mean amount of transfusion was 273.6, 129.6, and 920.8 ml, respectively. Preoperative haemoglobin values decreased by 1.6 ± 0.8, 1.8 ± 0.8, and 2.0 ± 0.9 mg/dl, respectively. CONCLUSION: Compared to intravenous administration, intra-articular administration of TNA seems to be more effective in terms of reducing blood loss and transfusion frequency. TNA may improve the general conditions of patients given TKA by maintaining a hemodynamically stable state, aiding in recovery, and reducing the chance of transfusion-associated side effects and complications. LEVEL OF EVIDENCE: II.

Cementless modular total hip arthroplasty in patients younger than fifty with femoral head osteonecrosis: minimum fifteen-year follow-up.

This study aimed to report the outcome of total hip arthroplasty (THA) with a modular femoral component in patients younger than fifty years with osteonecrosis of femoral head. Sixty-four osteonecrotic hips in fifty-five patients were available for clinical and radiographic analyses at minimum follow-up of fifteen-years. The mean Harris hip score improved from 36 points preoperatively to 92.7 points at final follow-up. Sixty-two (95.3%) hips demonstrated stable bone ingrowth. No hips showed loosening or required revision for aseptic loosening. Survivorship with an end point of stem revision for any reason was 93.8% and for aseptic loosening was 100% at 16.8years. We believe that cementless THA with a modular stem is a promising procedure for young and active patients with osteonecrosis of the femoral head.

Epidemiology of pediatric fractures before versus during the coronavirus disease 2019 pandemic.

Several studies have reported changes in the prevalence of childhood fractures between the prepandemic and coronavirus disease 2019 pandemic periods considering the overall decrease in activity during the latter. This review aimed to organize and summarize the global trends in pediatric fracture incidence. Our findings should help predict fracture patterns in the postpandemic period by identifying changes in the past and present, thus aiding patient management.

Substance P Inhibitor Promotes Tendon Healing in a Collagenase-Induced Rat Model of Tendinopathy.

BACKGROUND: The substance P-neurokinin 1 receptor pathway has been proposed as a therapeutic target for tendinopathy. However, there is a lack of evidence regarding its practical applications. PURPOSE: To investigate the therapeutic effects of substance P inhibitor (SPI) on inflamed tenocytes in vitro and in a collagenase-induced rat model of tendinopathy in vivo. STUDY DESIGN: Controlled laboratory study. METHODS: We analyzed the mRNA levels of inflammatory (cyclooxygenase [COX]-2 and interleukin [IL]-6) and tenogenic (Mohawk and scleraxis [SCX]) markers using reverse transcription quantitative polymerase chain reaction to demonstrate the effects of SPI on lipopolysaccharide-treated (inflamed) tenocytes. A collagenase-induced rat model of tendinopathy was created by injecting 20 µL of collagenase into the Achilles tendon. A behavior test using an incapacitance apparatus was performed to detect changes in postural equilibrium. The tendon specimens were obtained, and their gross findings were examined. The tensile strength was measured, and histopathological evaluation was performed (hematoxylin and eosin, alcian blue, and immunohistochemical staining). RESULTS: The mRNA levels of COX-2, IL-6, Mohawk, and SCX differed significantly between inflamed tenocytes and those treated with SPI. SPI improved the weight burden in a rat model of tendinopathy in a behavioral test. The specimens of the SPI group showed a normal tendon-like appearance. In the biomechanical test, the tensile strength of the SPI group was significantly greater than that of the tendinopathy group. In the histopathological evaluation, the degree of collagen matrix breakdown was mild in the SPI group. In alcian blue staining, only small focal depositions of proteoglycans and glycosaminoglycans were observed in the SPI group. The SPI group showed decreased expression of IL-6 and neurokinin 1 receptor. CONCLUSION: This study suggests that SPI has therapeutic effects on tendon healing and restoration in a collagenase-induced rat model of tendinopathy. CLINICAL RELEVANCE: SPI is a promising agent for tendinopathy in humans.

Surgical Outcomes and Predictive Factors of Medial Toe Excision for Polysyndactyly of the Fifth Toe.

BACKGROUND: We aimed to report surgical outcomes and analyze prognostic factors of medial toe excision for polysyndactyly of the fifth toe. METHODS: We reviewed the details of 139 consecutive patients who underwent surgery for postaxial polydactyly of the foot from 2009 to 2018. Among these, 83 patients (90 feet) with polysyndactyly of the fifth toe, treated by medial toe excision (between the duplicated toes) and reconstruction of the fourth web space using a dorsal rectangular flap, were included. The toe alignment and stability were restored by chondroplasty and soft tissue balancing without an osteotomy. A full-thickness skin graft was performed in 52 feet. The mean age at surgery was 27.1 ± 17.5 months and the mean duration of follow-up was 42.8 ± 24.9 months. RESULTS: At the last follow-up, a relatively small size of the reconstructed toe was observed in 19 feet (19/90, 21.1%). Proximal duplication level (metatarsal or proximal phalanx type) and preoperative hypoplasia of the remaining toe were related to the small postoperative size. Valgus deformity of the remaining toe was observed in 2 feet (2/90, 2.2%). We observed 17 cases with delayed healing or early postoperative wound infection. Among these, 7 cases (7/90, 7.8%) showed postoperative thickening or advancement of the web, which was not observed in cases without wound problems. No cases had functional disturbance or pain. CONCLUSION: The overall surgical outcomes were satisfactory without an osteotomy. Patients with a proximal duplication level or preoperative hypoplasia of the remaining toe should be informed of its possible small size postoperatively. LEVELS OF EVIDENCE: Level IV, retrospective case series.

Pro-Angiogenic and Osteogenic Effects of Adipose Tissue-Derived Pericytes Synergistically Enhanced by Nel-like Protein-1.

An important objective of vascularized tissue regeneration is to develop agents for osteonecrosis. We aimed to identify the pro-angiogenic and osteogenic efficacy of adipose tissue-derived (AD) pericytes combined with Nel-like protein-1 (NELL-1) to investigate the therapeutic effects on osteonecrosis. Tube formation and cell migration were assessed to determine the pro-angiogenic efficacy. Vessel formation was evaluated in vivo using the chorioallantoic membrane assay. A mouse model with a 2.5 mm necrotic bone fragment in the femoral shaft was used as a substitute for osteonecrosis in humans. Bone formation was assessed radiographically (plain radiographs, three-dimensional images, and quantitative analyses), and histomorphometric analyses were performed. To identify factors related to the effects of NELL-1, analysis using microarrays, qRT-PCR, and Western blotting was performed. The results for pro-angiogenic efficacy evaluation identified synergistic effects of pericytes and NELL-1 on tube formation, cell migration, and vessel formation. For osteogenic efficacy analysis, the mouse model for osteonecrosis was treated in combination with pericytes and NELL-1, and the results showed maximum bone formation using radiographic images and quantitative analyses, compared with other treatment groups and showed robust bone and vessel formation using histomorphometric analysis. We identified an association between FGF2 and the effects of NELL-1 using array-based analysis. Thus, combinatorial therapy using AD pericytes and NELL-1 may have potential as a novel treatment for osteonecrosis.

Long-Term Oral Bisphosphonate Compliance Focusing on Switching of Prescription Pattern.

BACKGROUND: Factors determining bisphosphonate compliance are not fully understood. We examined fluctuations in oral bisphosphonate dosing intervals to gauge therapeutic compliance in patients with osteoporosis. MATERIALS AND METHODS: Hospital data accruing between 2010 and 2017 were accessed to retrospectively study patients ≥50 years old (N=1873), each prescribed bisphosphonate at initial diagnosis of osteoporosis. The medication possession ratio (MPR), calculated as total days supplied divided by length of follow-up, served to measure therapeutic compliance. We compared MPRs of various prescription patterns (daily, weekly, monthly, and switch [ie, ≥1 change in pattern] groups). We also analyzed the impact of age, sex, fracture history, surgical history, and comorbidities. Multiple regression analysis was ultimately performed, using MPR as a dependent variable. RESULTS: In our cohort (mean follow-up=5.7±2.4 years), once weekly dosing was the most common prescription pattern (1223/1873, 65.3%), as opposed to monthly (366/1873, 19.5%) or daily (164/1873, 8.8%) dosing. A total of 120 patients (6.4%) comprising the switch group changed dosing patterns during the study period. MPR was significantly higher in the switch group (32.8±22.7) than in the other three groups (daily, 21.9±25.9; weekly, 22.7±27.3; monthly, 23.2±27.7). In multiple regression analysis, younger age (P<0.001), female sex (P=0.004), and switching of prescription pattern (decrease or increase frequency) were factors significantly associated with higher MPR, signaling better compliance. CONCLUSION: Better bisphosphonate compliance was associated with physician-modified dosing patterns. We therefore recommend adjustments of prescription intervals in poorly compliant patients requiring long-term treatment.

Surgical Results of Limb Lengthening at the Femur, Tibia, and Humerus in Patients with Achondroplasia.

BACKGROUND: Results of limb lengthening in patients with achondroplasia were previously reported in many studies. However, the reports of comparison among the three long bones (femur, tibia, and humerus) are rare, especially for the results of crossed lengthening (lengthening of one femur and contralateral tibia followed by that of the opposite side) for the lower limbs. The purpose of this study was to report the surgical results of a series of limb lengthening in achondroplastic or hypochondroplasia patients at our institution. METHODS: Fifteen patients (14 with achondroplasia and 1 with hypochondroplasia) underwent lower limb lengthening of the femur (n = 32) and tibia (n = 28), and 12 of them underwent crossed lengthening. Humeral lengthening was performed in 14 patients (n = 28). The mean age at the first operation was 11.7 years, and the mean follow-up duration was 66.7 months. The healing index, consolidation period index (duration of consolidation period/gained length), and other radiographic indices were analyzed. Limb length discrepancy and hip-knee-ankle alignment in lower limbs, and the occurrence of difficulties were assessed. RESULTS: The average gain in length for the femur, tibia, and humerus was 8.3 cm, 8.5 cm, and 7.4 cm, respectively. The mean healing index was 29.6 days/cm for the femur, 29.0 days/cm for the tibia, and 27.2 days/cm for the humerus. The mean consolidation period index was 14.7 days/cm for the humerus, which was significantly lower than that in the lower limb (17.3 days/cm for the femur and 17.8 days/cm for the tibia). Of the 12 who underwent crossed lengthening, five showed limb length discrepancy ≥ 1.0 cm. Among their 24 lower limbs, three showed valgus alignment ≥ 5° and one showed varus alignment ≥ 5°. Thirty-two pin site infections and three fractures were conservatively managed. Three femoral fractures, eight equinus deformities, and four cases with premature consolidation of the fibula were surgically treated. Obstacle and true complication related to humeral lengthening were not observed. CONCLUSIONS: Humeral lengthening was relatively effective and safe. Careful attention will be needed to avoid the occurrence of limb length discrepancy or malalignment in crossed lengthening.