Lengthening in congenital posteromedial bowing of tibia: a follow-up series at skeletal maturity.

PURPOSE: Congenital posteromedial bowing (CPMB) of tibia is a rare, usually self-resolving condition that is present at birth. The data on the long-term outcome of lengthening, choice of fixator, outcome in early and late age groups, and complications is sparse, hence the need for this study. METHODS: This retrospective study included 93 patients with 94 affected legs from 1991 to 2023. The patients were categorized into early (under 10 years) and late (10 years or above) intervention groups. Eighteen patients with nineteen lengthening episodes who attained skeletal maturity made the basis of this study and will be discussed in detail. RESULTS: The outcome for the lengthening group at maturity was satisfactory, with 5.53 cm of average length gained per lengthening episode, a mean LLD of 0.31 cm at final follow-up, a mean age of 23.63 years (range 14-38 years), and an average follow-up of 12.51 years (range 3-28 years) post-lengthening, but the procedure was associated with difficulties like ankle stiffness, tibial valgus, pin tract infections, and fractures through regenerate. CONCLUSION: This study represents a large single-centre series on CPMB. We recommend that surgery for lengthening should be done at an older age, close to skeletal maturity, wherever possible to reduce the risk of repeat lengthening procedures. Based on our experience, we recommend the use of a circular fixator. Uniplanar distractors should have an adequate number and spread of Schanz screws in each segment to reduce the risk of valgus malalignment of distracting segments of bone.

Effect of non-vascularized fibular harvest on the donor limb: radiological evaluation at a mean follow-up of twelve point eight years.

PURPOSE: The study is aimed at evaluating the long-term (at a minimum follow-up of 10 years) impact of non-vascularized fibular harvest on the donor limbs. METHODS: There were 27 donor limbs (n = 19 children) available for retrospective radiological review. The graft was obtained bilaterally in eight patients. The following parameters were evaluated in the follow-up radiographs: continuity/non-continuity of fibular regenerate, width of the regenerated fibula, distal fibular station, medial proximal tibial angle, posterior proximal tibial angle, lateral distal tibial angle (LDTA), anterior distal tibial angle, and tibia diaphyseal angulation (interphyseal angles). For analysis and comparisons, the donor limbs were compared to the healthy limbs (controls) of the children with unilateral harvest. Additionally, the impact of continuous and non-continuous fibular regeneration was separately analyzed. RESULTS: The mean child's age at the time of fibular harvest was four years. The mean follow-up was 12.8 years. The fibula was found regenerated in continuity in 22 limbs of 15 children (81.5%). When analyzed as a combined group (both continuous and non-continuous fibular regenerations), all the donor limb radiological parameters matched those of healthy limbs except LDTA (p = 0.04). In the subgroup analysis between non-continuous and continuous fibulae, significant abnormalities were again obvious in LDTA (p = 0.0001). The non-continuous fibulae were significantly lesser in width. All limbs with non-continuous fibular regeneration manifested ankle valgus. CONCLUSIONS: The non-vascularized fibula emerged as a relatively safe procedure in the long term with minimal affections of the knee, ankle, or tibial anatomy when longitudinal integrity of fibula was restored. The non-regenerations of the fibula may be prone to developing ankle valgus.

Donor-Site Complication of Severe Valgus Ankle Deformity in an Adult With Ehlers-Danlos Syndrome Following Free Vascularized Fibular Grafting.

Valgus deformity of the ankle joint is a well-known and relatively common donor-site complication of free vascularized fibular graft harvest in children. Due to children having naturally greater ligamentous laxity than adults, the tibiofibular syndesmosis can be compromised with the loss of the fibular shaft, leading to valgus ankle deformity (VAD). Syndesmotic stabilization with screws is commonly recommended in subsets of pediatric patients at the greatest risk of this complication. In adults, the occurrence of VAD is seldom reported in the literature following fibular graft harvest. As such, no recommendation for syndesmotic stabilization exists in the adult population. We present a case of end-stage VAD in an adult patient with Ehlers-Danlos syndrome (EDS) following free vascularized fibular graft harvest. We hypothesize that other patients with generalized joint hypermobility may face the same complication and, thus, recommend the consideration of syndesmotic stabilization or primary syndesmotic fusion at the time of graft harvest in this patient population.

Approach to the Ankle in Adult Acquired Flatfoot Deformity.

Adult acquired flatfoot is a progressive deformity of the foot and ankle, which frequently becomes increasingly symptomatic. The posterior tibial tendon is most commonly associated with the deformity. A targeted physical examination with plain film radiographs is the recommended initial assessment, which will further guide a physician toward procuring more advanced imaging or toward surgical intervention. In this chapter the authors review the current literature of their approach to the treatment of the ankle in end stage of adult acquired flatfoot deformity.

Design of a New "U"-shaped Staple and Its Clinical Application in Postoperative Ankle Valgus of Congenital Pseudarthrosis of the Tibia in Children.

OBJECTIVE: There has been a lack of suitable epiphysis blocking materials due to the characteristics of less tissue coverage and narrow epiphysis in children's distal tibial medial malleolus. Therefore, this study is to investigate the clinical efficacy and safety of a new "U"-shaped staple in the treatment of postoperative ankle valgus of congenital pseudarthrosis of the tibia (CPT). METHOD: According to the inclusion and exclusion criteria, 33 patients with postoperative ankle valgus of CPT were treated with new "U"-shaped staples from May 2013 to September 2019. The deformity of ankle valgus was gradually corrected by implanting a new "U"-shaped staple on the medial side of the distal tibia. Clinical indexes such as the operation time, intraoperative bleeding and hospital stay were observed. Tibiotalar angle was selected as the evaluation index of ankle valgus. American Orthopedic Foot & Ankle Society (AOFAS) scale was used for clinical evaluation of ankle function. The tibiotalar angle, deformity correction rate and complications were evaluated by preoperative, postoperative and last follow-up imaging data. Student's t-test was used for statistical analysis. RESULTS: Thirty-three patients, including 12 males and 21 females were included. All the patients were followed up for at least 14 months, with an average of 35 months. The average operation time was 23 (15-40) min, the average amount of intraoperative bleeding was 7.5 (4-10) mL, and the average hospital stay was 4.2 (3-6) days. The intraoperative tibiotalar angles of all patients were 74.2° ± 4.6°, the tibiotalar angle were 86.8° ± 4.9° when internal fixation was removed, and the tibiotalar angles at the last follow-up were 84.3° ± 5.9°. The average orthopedic rate was 0.68° per month. No patients suffered from serious complications such as screw prolapse, osteomyelitis, wound infection, etc. Postoperative wound pain complications occurred in two patients, which were relieved after conservative treatment. The AOFAS score improved from 46.2 ± 9.4 before the operation to 74.6 ± 5.7 at the last follow-up (P < 0.01). The ankle movement was good without joint stiffness. There was no epiphyseal plate injury after the removal of internal fixation. CONCLUSION: The new "U"-shaped staple is characterized by simple implantation, low notch, lower risk of fixation failure and close fitting with cortical bone. It is a safe and effective internal fixation system for the treatment of ankle valgus in children.

Improved distribution of leg forces after fibular resection and synostosis.

PURPOSE: Genu varum- a common symptom in achondroplasia- may lead to ankle valgus in children. Ankle valgus may be mitigated by tibiofibular synostosis, but this is not always the case. The mechanical environment around the growth plates plays an important role in ankle valgus. The purpose of this project is 1) to determine the strain through the distal fibular growth plate before and after tibiofibular synostosis, and 2) postulate whether the change in strain affects ankle valgus. This project measured the distal fibular strain in a porcine hind leg model. METHODS: The lower legs of seven pigs were removed, instrumented with strain gauges, and loaded compressively in a material testing machine. Loads were applied at three phases: 1) the intact leg, 2) leg with fibula resected, and 3) leg with fibula resected and tibiofibular synostosis. Mean strains were compared between phases using a mixed affect model. The significance level was adjusted for multiple comparisons using the Bonferroni method. RESULTS: Phase 1, intact leg, had the highest strain value at 1247.9µÉ›. In phase 2, the mean strain was 106.2µÉ›. In phase 3, the compressive mean strain dropped to 477.4µÉ›, which is 38% of the strain in phase 1. Standard error was 86.8µÉ›; p < 0.001. CONCLUSION: Results indicate that more of the force through the leg is transmitted through the tibia after fibular resection and tibiofibular synostosis, which improves the balance of forces through the leg.

Post-operative Complication at the Donor Site of Fibular Free Flap in a Pediatric Patient.

The fibular free flap is most frequently used for reconstructing the mandible owing to the adequate length of the bone with a reliable blood supply. It has a long vascular pedicle with adequate vessel diameter for anastomosis and also a good amount of skin paddle for coverage. However, the reports of post-operative complications at the donor site among pediatric patients are scarce in the literature. We present a pediatric case of ankle valgus deformity following vascularized fibular harvest.

Radiographic Analysis and Clinical Efficacy of Hindfoot Arthrodesis With Versus Without Cotton Osteotomy in Stage III Adult Acquired Flatfoot Deformity.

Forefoot varus develops as a result of longstanding adult-acquired flatfoot deformity (AAFD). This occurs with varying degrees of deformity and flexibility. Residual forefoot varus following hindfoot realignment in AAFD can lead to lateral column loading and a persistent pronatory moment in efforts to reestablish contact between the forefoot and the ground. The Cotton osteotomy may serve as a reasonable adjunct procedure to help avoid complications and poor outcomes associated with residual forefoot varus in patients undergoing hindfoot arthrodesis for stage III AAFD. The aim of this study was to compare the radiographic outcomes in patients undergoing isolated hindfoot arthrodesis to patients undergoing hindfoot arthrodesis with adjunctive cotton osteotomy. We retrospectively reviewed 47 patients matched based upon age, sex, and comorbidities who underwent hindfoot reconstruction for the treatment of stage III AAFD between 2015 and 2019. A retrospective radiographic review was performed on standard weightbearing radiographs including anterior-posterior and lateral views preoperatively, postoperatively at the initiation of full weightbearing, and at final follow-up. Statistical analysis utilizing paired t test to calculate p values where <.05 was statistically significant. At final follow-up, radiographic measurements showed statistically significant differences in CAA, calcaneal inclination, talo-calcaneal, and talar tilt (p value <.05). The Cotton osteotomy group showed a quicker return to presurgical activity level and a decreased incident of tibiotalar valgus. Our study suggests that the Cotton osteotomy can address residual forefoot varus and potentially prevent further progression of ankle valgus in AAFD when used in combination with hindfoot arthrodesis.

Risk factors for ankle valgus in children with hereditary multiple exostoses: a retrospective cross-sectional study.

PURPOSE: The aim of this study was to identify risk factors for ankle valgus in children with hereditary multiple exostoses (HME). METHODS: We retrospectively reviewed the medical records of patients with HME who were examined at our hospital between 2010 and 2020. Patients' age and sex were recorded along with radiographic variables including mechanical axis deviation (MAD), mechanical lateral distal tibia angle (LDTA), fibula/tibia length ratio (F/T); distal fibula station according to Malhotra's classification, location of exostoses at the ankle joint and fibular neck/physis width (N/P) ratio, which were measured from radiographs. Binary logistic regression analysis was performed to identify significant independent risk factors for ankle valgus. RESULTS: There were 61 children (20 girls and 41 boys; 122 ankles) who met the inclusion criteria. The mean age was 10.4 years (sd 3.4) and mean LDTA was 83° (sd 7°). Ankle valgus was found in 64 ankles (52%). In addition to younger age, exostoses involving the lateral aspects of the distal tibial and the medial aspect of the distal fibula (odds ratio (OR) = 4.091; 95% confidence interval (CI) 1.065 to 15.712; p = 0.040), F/T ratio < 0.96 (OR = 4.457; 95% CI 1.498 to 13.261; p = 0.007) and N/P ratio > 1.6 (OR = 2.855; 95% CI 1.031 to 7.907; p = 0.043) were associated with an increased risk of developing ankle valgus, while sex and MAD were unrelated to its occurrence. CONCLUSION: Young age, exostoses involving both the distal tibia and fibula, the F/T ratio < 0.96 and fibular N/P width ratio > 1.6 seemed to be risk factors of developing ankle valgus. LEVELS OF EVIDENCE: Prognostic studies, IV.

Hemiepiphysiodesis Using a Transphyseal Screw at the Medial Malleolus for the Treatment of Ankle Valgus Deformity.

BACKGROUND: The purpose of this study is to report outcomes of transphyseal screw hemi-epiphysiodesis at the medial malleolus for the treatment of valgus ankle deformity. METHODS: An institutional review board-approved retrospective review was done of 24 patient charts. Lateral distal tibial angle (LDTA) was measured preoperatively and at final follow-up. RESULTS: The average change in LDTA was 8.3 degrees (SD 4.9 degrees; range 0-19 degrees). The average rate of correction was 0.4 degrees per month (SD 0.3; range 0-1.4). CONCLUSION: Medial malleolar transphyseal screw hemiepiphysiodesis is a simple, effective, and safe treatment for valgus ankle deformity in skeletally immature children. LEVEL OF EVIDENCE: Level IV, case series.

Coronal malalignment of lower legs depending on the locations of the exostoses in patients with multiple hereditary exostoses.

BACKGROUNDS: Though malalignment of lower legs is a common pathologic phenomenon in multiple hereditary exostoses (MHE), relationship between locations of exostoses and malalignment of lower legs remains unclear. This study examined radiographs of MHE patients in an attempt to evaluate the tendency of coronal malalignment of lower legs with different location of exostoses on lower legs consisting of two parallel long bones. METHODS: Between 2000 and 2017, we retrospectively reviewed the anteroposterior films of the teleo-roentgenographics of 63 patients with MHE. The patients were classified into four different groups depending on the locations of the exostosis, which occurred on both proximal and distal tibiofibular joints (A), proximal tibiofibular joint (B), distal tibiofibular joint (C), and not for the tibiofibular joint area (D). To evaluate the influence of the location of exostoses on coronal malalignment of lower legs, medial proximal tibia angle (MPTA), lateral distal tibia angle (LDTA), and fibular shortening were analyzed for each group. RESULTS: Significant difference was observed in multiple comparative analyses for each of the four groups. On MPTA radiologic analysis, group A showed greatest value with significant difference compared with groups C and D (vs. (B): p = 0.215; vs. distal joints (C): p = 0.004; vs. (D): p = 0.001). Group B showed significant difference only with group D (vs. distal joints (C): p = 0.388; vs. (D): p = 0.002), but for group C and D showed no significant difference. For LDTA, only group A showed significant difference compared to other groups (p < 0.001). With regard to tibiofibular ratio for evaluation of fibular shortening, group A showed the lowest ratio (vs. (B): p = 0.004; vs. (C): p = 0.655; vs. (D): p < 0.001). Group C also presented the significant lower ratio than group D (p = 0.002). CONCLUSIONS: For evaluation of the coronal malalignment of lower legs in MHE patients, not only ankle around the distal tibiofibular joint but also proximal tibiofibular joint should be examined, in that, lower limb deformity occurred by two parallel long bone which has self-contained joint. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

The regeneration at non vascularized fibular harvest site and development of ankle valgus in donor leg-investigations done over two time points.

INTRODUCTION: We retrospectively observed the fibular regeneration in non vascularized harvest in children and development of ankle valgus at 2 time points to find any possible relationship between them. MATERIAL AND METHODS: A 6 month period was chosen as the first time frame to assess regeneration and ankle valgus. Radiographs at this time and a subsequent follow up were studied for regeneration, lateral distal tibial ankle (LDTA) and fibular station. The donor sites were divided into complete and incomplete regeneration groups and compared statistically. RESULTS: There were 12 patients with 18 harvested fibulae. Ten out of 18 fibulae (56%) had complete longitudinal regenerate at 6 months. Two fibulae underwent delayed union. Of 8 incomplete regenerates at 6 months, 6 (75%) were also incomplete beyond a follow up of 2.75 years. Incomplete group had radiological ankle valgus in 6 legs (75%) at 6 months increased to 7 at follow up. Further, LDTA for incomplete group was significantly lower than complete group (p = 0.025) at 6 months. CONCLUSIONS: More than half of harvested legs (56%) had complete longitudinal fibular regeneration at 6 months. Of incomplete regenerates at 6 months, three fourth remained so beyond 2.5 years. Ankle valgus was found strongly related to long standing fibular non regeneration. Radiological ankle valgus developed early in the incomplete regenerate group.

Fibular donor site following non vascularized harvest: clinico-radiological outcome at minimal five year follow-up.

PURPOSE: The long-term donor site outcome of non vascularized fibular harvest in paediatric age group is not well studied. We evaluated clinical and radiological characteristics of fibular harvest site in children at a minimum five year follow-up. METHODS: The patients with donor legs underwent both physical and radiographic examination. Clinical parameters evaluated were pain, neuromuscular weakness, and standing tibiocalcaneal hindfoot valgus in the donor limb. Radiologically, longitudinal non continuity in regeneration, medullary canal reformation, Malhotra grading, and lateral distal tibial angle (LDTA) were documented. RESULTS: Sixteen patients (18 legs) were available for follow-up. The average follow-up was 6.23 ± 1.1 years. None of the patients reported pain or neuromuscular weakness related to the donor leg. Five patients reported cosmesis issues related to exaggerated ankle valgus. Medullary canal restoration was seen in 3/14 regenerated fibulae. Harvested legs had overall higher fibular station than contralateral unintervened ankles. Non continuity in regeneration were seen in 4/18 legs. There was clinical hindfoot valgus, abnormal LDTA, and fibular station in these patients. Clinical valgus matched better with a combination of fibular station and LDTA (83.3%) rather than fibular station or LDTA (75%) alone. CONCLUSIONS: Fibular regeneration was complete in more than 75% legs at follow-up of > five years but remodeling and reformation of medullary canal was delayed. Long-term fibular non regeneration was persistently responsible for development of ankle valgus deformity. Middle lower third fibular junction is critical area for non restoration of medullary canal and non continuity.

Ankle reconstruction and lengthening strategy in type II fibular hemimelia: a report of two cases.

Limb lengthening of fibular hemimelia is associated with progressive ankle valgus deformity. We reported a successful tibial lengthening in fibular hemimelia without recurrence of ankle valgus in 2 cases. The procedure involved 2 stages. First stage was a resection of the fibular remnant followed by a bending osteotomy through the distal tibial physis before the age of 2 years old. The second stage was a tibia lengthening up to 25% of its original segmental length performed at the age of 5 years old. There was neither progressive ankle valgus nor distal tibial growth arrest observed at 4 years follow-up.

Effect of Foot Progression Angle and Lateral Wedge Insole on a Reduction in Knee Adduction Moment.

This study evaluated the effect of foot progression angle on the reduction in knee adduction moment caused by a lateral wedged insole during walking. Twenty healthy, young volunteers walked 10 m at their comfortable velocity wearing a lateral wedged insole or control flat insole in 3 foot progression angle conditions: natural, toe-out, and toe-in. A 3-dimensional rigid link model was used to calculate the external knee adduction moment, the moment arm of ground reaction force to knee joint center, and the reduction ratio of knee adduction moment and moment arm. The result indicated that the toe-out condition and lateral wedged insole decreased the knee adduction moment in the whole stance phase. The reduction ratio of the knee adduction moment and the moment arm exhibited a close relationship. Lateral wedged insoles decreased the knee adduction moment in various foot progression angle conditions due to decrease of the moment arm of the ground reaction force. Moreover, the knee adduction moment during the toe-out gait with lateral wedged insole was the smallest due to the synergistic effect of the lateral wedged insole and foot progression angle. Lateral wedged insoles may be a valid intervention for patients with knee osteoarthritis regardless of the foot progression angle.

Reconstruction of the Pediatric Lateral Malleolus and Physis by Free Microvascular Transfer of the Proximal Fibular Physis.

Traumatic injury to the pediatric growth plate can result in growth disturbances, late angular deformity, and limb length inequalities. Complete traumatic loss the entire growth plate complex (physis, epiphysis, and distal metaphysis) of the ankle can lead to severe joint instability and loss of function. In the growing child, physeal preservation is paramount; however, the reconstructive options are limited. We report a case of post-traumatic loss of the distal fibular physis resulting in severe ankle valgus in a pediatric patient after a Gustilo grade 3B open injury. Ankle valgus secondary to post-traumatic necrosis of the lateral ankle physeal complex was successfully managed by microvascular free transfer of the ipsilateral proximal fibula physis. The 24-month follow-up examination demonstrated continued growth of the free vascularized physeal graft and a stable ankle. The donor site had healed without incident. The patient was able to return to age-appropriate play, sports, and social integration.

Ankle and subtalar synovitis in a ball-and-socket ankle joint causing posterolateral painful coarse crepitus: a case report.

A 17-year-old girl with bilateral ball-and-socket ankles reported left medial heel pain. Her left heel had gone into a varus position on tiptoeing, and a painful clunk had occurred when returning to normal standing. The clunk persisted after physiotherapy and treatment with an orthosis. Subtalar arthroscopy and peroneal tendoscopy showed mild diffuse synovitis of the ankle joint, especially over the posterior capsule, and a patch of inflamed and fibrotic synovium at the posterolateral corner of the subtalar joint. The clunk subsided immediately after arthroscopic synovectomy and had not recurred during 5 years of follow-up. We found no other reported cases of ankle and subtalar synovitis occurring in patients with a ball-and-socket ankle joint.

Surgical decision making for stage IV adult acquired flatfoot disorder.

Adult acquired flatfoot deformity is a debilitating musculoskeletal condition affecting the lower extremity. Posterior tibial tendon dysfunction (PTTD) is the primary etiology for the development of a flatfoot deformity in an adult. PTTD is classified into 4 stages (with stage IV subdivided into stage IV-A and IV-B). This classification is described in detail in this article.

Correction and recurrence of ankle valgus in skeletally immature patients with multiple hereditary exostoses.

BACKGROUND: Ankle valgus is encountered in children with a variety of congenital musculoskeletal disorders, including multiple hereditary exostoses (MHE). Guided growth with temporary distal tibial medial hemiepiphysiodesis (DTMH) may correct the deformity; however, exostoses about the ankle commonly observed in MHE patients may hinder correction and increase the risk of recurrence. Thus, the purpose of this study was to review the outcomes of DTMH in treatment of ankle valgus in MHE versus other diagnosis (non-MHE). METHODS: Medical records and radiographs of patients undergoing DTMH for ankle valgus between January 1, 2005, and November 1, 2010, at a single pediatric orthopedic hospital were retrospectively analyzed. Radiographs obtained preoperatively and at 6-month intervals postoperatively were reviewed and the tibiotalar angle was measured. RESULTS: Fifty-eight ankles in 41 patients met inclusion criteria, with minimum follow-up of 12 months (mean, 34 months). Mean age was 10 years (range, 4-14 years). MHE was the most common underlying diagnosis (19 ankles, 33%). The rate of tibiotalar angle correction (mean ± standard deviation) with hardware in place was 0.37 ± 0.28 deg/mo in MHE ankles and 0.51 ± 0.42 deg/mo in non-MHE ankles (P = .161). Following hardware removal, the rate of recurrence was faster in MHE (0.29 ± 0.25 deg/mo) compared with non-MHE ankles (0.12 ± 0.19 deg/mo) (P = .059), and more total recurrent valgus deformity was observed in MHE (7.8 ± 8.2 degrees) than non-MHE ankles (3.4 ± 4.6 degrees) (P = .08) over a similar follow-up period (mean 23.4 vs 23.6 months, respectively), with differences approaching statistical significance. CONCLUSION: MHE is a common cause of ankle valgus in children. Guided growth interventions in this population can be successful but require special consideration given the potential for relatively gradual deformity correction and rapid recurrence following hardware removal in the skeletally immature. LEVEL OF EVIDENCE: Level III, retrospective comparative study.