Tibial Deformity Research Articles

Surgical Correction of Posttraumatic Varus Deformity of the Distal Tibia Due to Medial Growth Arrest in Children and Adolescents: Surgical Technique

Background: Varus deformity of the distal tibia secondary to epiphyseal fracture and partial growth arrest is relatively common. Growth arrest of the medial part of the epiphysis leads to varus deformity of the distal tibia and fibular overgrowth. If the deformity is left untreated, the malalignment may lead to irreversible damage and early ankle joint osteoarthritis in the long term. Several surgical techniques have been described in the literature to achieve correction and prevent late complications. These include the closure of the remaining epiphysis and various osteotomies around the ankle, using internal and external fixation. Materials and Methods: We report a technique that includes medial open wedge supramalleolar osteotomy, insertion of a structural cortical allograft and fixation with an anatomically contoured locking plate, completion of closure of the distal tibial physis, and distal fibular epiphysiodesis to prevent tibiofibular relations distortion. Part of this protocol is osteotomy of the distal fibula to prevent excessive pressure on the talus, and at the end of the operation, fibular fixation should be performed as well. In children with open physis and potential for significant leg length discrepancy, we recommend closure of the contralateral physis of the distal tibia and fibula. To the best of our knowledge, precise details of this protocol have not been described. Conclusion: We believe that this protocol is a reliable, accurate, and relatively simple method that provides not only anatomic correction and restoration of the ankle joint to prevent early ankle and subtalar arthritis but also addresses late complications, such as ipsilateral fibular overgrowth and limb length discrepancy.

A novel smoothed (SMO) point mutation in congenital tibial hemimelia: a case report

BackgroundCongenital tibial hemimelia (CTH [MIM: 275220]) is a rare congenital limb deficiency that manifests as a shortened, curved, dysplastic or absent tibia with polydactyly. In previous studies, mutations of a distant sonic hedgehog (SHH) cis-regulator (ZRS) and a Shh repressor (GLI3) were identified.Case presentationHere, we admitted a 20-month-old boy who manifested with right tibial deformity, varus foot, ankle dislocation, and ipsilateral preaxial polydactyly. After genetic sequencing and data analysis, the results revealed a 443 A > G mutation in the father and a 536 C > T mutation in the mother in exon 2 of the Smoothed (SMO) gene at 7q32.1, with the coexistence of both mutant alleles in the proband/patient.ConclusionsOur report suggests that even though not previously reported, SMO mutations may be associated with limb anomalies such as tibial hemimelia via Hh signaling in humans and has implications for genetic counseling.

Periarticular knee osteotomies for pre-arthritic deformities in the frontal plane : Indications and surgical techniques

Currently, periarticular knee joint osteotomies are an integral part of the treatment of early arthritic deformities in the knee joint. Analysis of the deformity is performed with astandardized full-leg standing x‑ray of both legs, as well as alateral x‑ray of the knee joint that includes 2/3 of the proximal tibial shaft. An MRI examination of the knee joint is obtained to assess the articular cartilage, the ligaments and menisci. Torsion angle measurements with the CT/MRT supplement the diagnostics if necessary. Knowledge of normal physiological values and their standard deviations of the mechanical leg axis and the joint angles around the knee is obligatory. The osteotomy is performed as close as possible to the femoral and/or tibial deformity. Postsurgical deformities including pathological patella position or asignificant difference in leg length must be prevented. Adescription of proximal tibia opening or closing wedge osteotomies based on the nomenclature of the joint angles by Paley is presented. The indications for the various osteotomy techniques in the coronary plane are discussed in detail.

Limb length deceleration or coronal plane deformity correction using tension band plates: does plate configurations determine the intraarticular deformity of proximal tibia?

We studied whether the two-plate tension band configuration is more prone for intraarticular deformations than the single plate application used for coronal plane deformities (CPD). The study was based on radiological chart review (retrospective cross-sectional) of records of children [15 patients (30 plates) with limb length discrepancies (LLD) and 20 patients (36 plates) with CPD]. Interscrew angle, slope angle, and roof angle were compared in the initial postoperative and final radiographs to determine changes of tibial morphology. The mean patient age and follow up for the LLD and CPD groups respectively were 6.5 years, 39.8 months and 8.1 years, 15.5 months respectively. The interscrew angles widened between initial and final radiographs in the CPD group and for both sides in the LLD group. The initial and final slope angles were not significantly different in both LLD and CPD groups. Similar trend was observed for roof angle in either group. In the intergroup comparisons between LLD and CPD group, the slope angle of medial/lateral operated side in LLD group versus that of the operated side in CPD group matched statistically in the final radiographs. Similarly, the final roof angle in LLD and CPD groups was statistically similar. No significant intraarticular morphological change was demonstrated following tension band plating epiphysiodesis of the proximal tibia for our series involving young children. It was observed neither with the two-plate configuration used for limb length decelerations nor with the single plate application for coronal plane corrections.

The Perils of Sleeper Plates in Multiple Hereditary Exostosis: Tibial Deformity Overcorrection Due to Tether at Empty Metaphyseal Hole.

Hemi-epiphysiodesis is the mainstay of treatment for angular deformities at the knee in children with multiple hereditary exostosis (MHE). Upon deformity correction, the metaphyseal screw may be removed from the hemi-epiphysiodesis plate, the sleeper plate technique, with anticipated reimplantation of the metaphyseal screw should the original deformity recur. The aim of the present study is to compare the incidence of complications with the sleeper plate technique with complete plate removal in an MHE cohort. Patients under the age of 18 with MHE who underwent hemi-epiphysiodesis of the proximal tibia and/or distal femur between February 1, 2016, and February 6, 2022 with a minimum 2-year follow-up or follow-up to skeletal maturity were identified via ICD-10 codes. Patient charts and radiographic images were reviewed to assess for the bone(s) treated, the use of sleeper plates, and whether any complication occurred, including overcorrection from bony ingrowth at the empty holes or deformity recurrence. In 13 patients, 19 knees underwent hemi-epiphysiodesis at 30 sites; 13 distal femoral and 17 proximal tibial. Of 30 plates, 18 (60%) were removed completely upon deformity correction and 3 (10%) did not require removal due to skeletal maturity. Four of 13 (30.8%) femoral plates and 5 of 17 (29.4%) tibial plates were left as sleeper plates. All 5 tibial sleeper plates developed bony ingrowth into the empty metaphyseal screw hole, which led to unintended progressive deformity overcorrection. In the majority of cases, the deformity was addressed by the removal of the plate and exophytic bone and hemi-epiphysiodesis on the other side of the affected proximal tibia with subsequent resolution of the deformity. All tibial sleeper plates developed bony ingrowth into the screwless metaphyseal hole. The bony ingrowth functioned as a tether, resulting in progressive deformity overcorrection. Sleeper plates should be avoided at the proximal tibia in patients with MHE, and extreme caution should be exercised when considering this technique at the distal femur or other sites. Level III-retrospective comparative study.

Poster 298: Establishment of a Novel Distance and Angle and Determining Their Relationship with the ACL

Poster 298: Establishment of a Novel Distance and Angle and Determining Their Relationship with the ACL

Correction of Tetratorsional Malalignment of the Lower Extremities Improves Patient-Reported Outcomes.

Axial malalignment of the bilateral femurs and tibias, previously known as "miserable" malalignment, now renamed tetratorsional malalignment (TTM), presents with hip and/or knee pain refractory to nonoperative treatment. We sought to investigate whether bilateral rotational osteotomy of the femur and tibia leads to improvement in a deformity-specific patient-reported outcome measure (PROM). A retrospective review of patients who underwent staged rotational correction of the bilateral femur and tibias was performed. Computed tomography (CT) was used to measure the preoperative rotational profile and plan the surgical correction. Stabilization was predominantly with intramedullary nails. The primary outcome measure was the Limb Deformity-modified Scoliosis Research Society (LDSRS) score. Secondary outcomes included change in mechanical limb alignment and complications of the procedure. Sixteen patients (13 female and 3 male) with average age of 23.1 years (range: 15-36 years) underwent 4-segment rotational correction. The averages for femoral and tibial deformity correction were 23.5° (6.2° SD) and 20.9° (5.2° SD), respectively. The total LDSRS score improved from 3.67 (0.3 SD) to 4.39 (0.3 SD) (P = .001). The LDSRS sub-scores for function, pain, and self-image also significantly improved. In patients not undergoing concurrent coronal deformity correction, the limb mechanical axis was not significantly changed. No additional procedures were performed to obtain bone union. Three patients required peroneal nerve decompression following the index procedure, and all neurologic symptoms resolved. This retrospective review suggests that correction of TTM of the lower extremities may lead to improvements in function, pain, and self-image. There were minimal complications and no iatrogenic deformity among 16 patients reviewed. The new diagnosis, TTM, is descriptive of this debilitating condition without communicating a negative patient image.

High tibial osteotomy for acute correction and subsequent gradual tensioning of the posterolateral knee ligament complex in treating genu varum combined with a lateral thrust using the Ilizarov technique in adults: surgical technique and early results

ObjectiveTo report the early results of using the Ilizarov technique in performing medial wedge opening high tibial osteotomy (MWOHTO) combined with gradual tensioning of the posterolateral corner in adult patients presenting with genu varum (GV) and lateral thrust.MethodsA prospective case series study included 12 adult patients with a mean age of 25.2 ± 8.1 years who presented with GV deformity associated with lateral thrust. They were evaluated clinically using the “hospital for special surgery” (HSS) knee scoring system. Radiological evaluation was performed using long film from hip to knee to ankle (HKA) radiographs; the overall mechanical alignment was measured as the HKA angle, the upper tibial deformity was measured as the medial proximal tibial angle (MPTA), and the joint line convergence angle (JLCA) was measured. Surgical technique included using Ilizarov for MWOHTO below the level of the tibial tubercle, acute correction of the GV deformity, fibular osteotomy, and gradual distalization of the proximal fibula.ResultsAfter a mean follow-up of 26.3 ± 6.4 months, all osteotomies were united. All patients achieved fibular osteotomy site bony union except two with a fibrous union. The HSS score showed improvement from a mean preoperative score of 88.7 ± 7.6 to a postoperative 97.3 ± 3.9 (P < 0.05). The overall mechanical lower limb alignment improved significantly from a mean preoperative HKA of 164.5 ± 3.2 to a postoperative 178.9 ± 1.6 (P < 0.05). The MPTA improved significantly from 74.6 ± 4.1 to 88.9 ± 2.3, as well as the JLCA from 12.17 ± 1.9 to 2.3 ± 1.7 (P < 0.05). Grade 1 pin tract infection was developed in four patients and was treated conservatively. In two patients, mild pain over the fibular osteotomy site was relieved over time. The lateral thrust reoccurred at the last follow-up evaluation in the two poliomyelitis patients.ConclusionMWOHTO, concomitant with tensioning the knee lateral soft tissue structure at the same setting through applying an Ilizarov apparatus, showed promising functional and radiological outcomes.

Accuracy of the hexapod external fixator in treating tibial angular deformities with or without limb length discrepancy: a retrospective study.

Hexapod external fixator systems allow simultaneous deformity correction in multiple planes as well as limb lengthening. The aim of this study is to evaluate the accuracy of a hexapod frame (smart correction frame) in different types of tibial deformities requiring correction with or without lengthening. A total of 54 tibial angular deformities and limb length discrepancies operated with a hexapod frame between January 2015 and January 2021 were classified into four groups: "Group A (n = 13): only lengthening," "Group B (n = 14): lengthening and uniplanar correction," "Group C (n = 16): only uniplanar correction," and "Group D (n = 11): biplanar correction." The accuracy of angular deformity correction/lengthening was calculated by dividing the actual correction/lengthening achieved after frame removal by the preoperative planned lengthening/correction. The lengthening accuracy in Group A and Group B was 96.3 ± 7.1% and 95.7 ± 5.9%, respectively (P = 0.685). The angular deformity correction accuracy was 85.1 ± 9.9% for Group B, 85.2 ± 13.9% for Group C, and 80.2 ± 18.4% for Group D (P = 0.852). A revision program was performed in six cases (1 in Group B, 1 in Group C, and 4 in Group D) for full correction of the deformities. The accuracy of tibial lengthening is high with the hexapod frame and is minimally affected by simultaneous deformity correction; however, the accuracy of angular correction slightly reduces as the deformity becomes more complex. Surgeons should be aware that reprogramming may be required after complex deformity correction.

Treatment of Concomitant Congenital Pseudarthrosis of the Fibula With Propeller Periosteal Flap.

Congenital pseudarthrosis of the fibula is not an uncommon condition to accompany congenital pseudarthrosis of the tibia. Persistence of the fibular pseudarthrosis has been linked to inferior outcomes including tibial union and alignment, refractures, and ankle alignment. In this report, we present the results of a pedicled periosteal propeller flap technique for the treatment of fibular pseudarthrosis. Ten children with an average age at surgery of 5.3 years who had congenital pseudarthrosis of both tibia and fibula were studied. The tibia was treated with free vascularized fibular grafting, and the ipsilateral fibula was treated with a technique after resection of the pseudarthrosis. A periosteal flap from the proximal healthy part of the fibula is harvested off the bone, rotated 180° based on a branch from the peroneal vessels to cover the fibular defect and fashioned in the form of a tube filled with bone fragments. The periosteal flap size ranged from 5 to 7 cm. Follow-up averaged 37.2 months. The tibia was united in all cases; in 2 of them, refractures occurred and healed with conservative management. The fibula was united in 8 cases. At final follow-up, 5 cases showed residual tibial deformity, and 5 showed residual ankle deformity. Average leg-length discrepancy was 1.4 cm (0-3 cm). The pedicled periosteal propeller flap presents a useful new technique for managing concomitant congenital fibular pseudarthrosis.

WITHDRAWN: Déformation en valgus négligée dans les fractures de la diaphyse tibiale, avec ou sans atteinte fibulaire, chez l’enfant : cause du valgus résiduel à deux ans de recul

BackgroundChildren with a tibial shaft fracture often present with valgus malalignment, even when anatomical reduction had been achieved at the fracture site. Pediatric bony structure has more elastic bones than that of adults, it can cause bowing deformity. Therefore, we evaluated pediatric tibial shaft fracture for the presence of bowing deformity, associated risk factors, and its clinical significance. HypothesisThere is an overlooked bowing deformity in pediatric tibial shaft fracture. Patients and methodsIn total, 57 tibial shaft fracture patients aged 2 to 15 years with Risser stage 0 were retrospectively reviewed. Clinicoradiologic factors and radiographs taken within 3 post-traumatic months and at 2-year follow-up were assessed. To evaluate the tibial bowing deformity, the tibial interphyseal angle and tibial shaft angle were measured, and their differences were calculated as a tibial bowing angle. ResultsMultivariate analysis revealed the tibial shaft fracture with fibular involvement is significantly associated with a higher initial tibial bowing angle (valgus deformity). The tibial bowing angle did not change over 2-year follow-up. A high initial tibial bowing angle (≥ 5°) was a significant risk factor for the persistence of valgus malalignment. DiscussionPediatric tibial shaft fractures with/without fibular involvement carry the risk of valgus bowing deformity, which may not develop during post-traumatic growth but may be present at the time of injury. The risk is high if the tibial fracture is accompanied by a fibular fracture. This tibial deformity presents limited remodeling potential at 2-year follow-up. Level of evidenceIV, retrospective study.

Overlooked valgus bowing deformity in pediatric tibial shaft fractures with/without fibular involvement: Cause residual valgus alignment in 2-year follow-up

BackgroundChildren with a tibial shaft fracture often present with valgus malalignment, even when anatomical reduction had been achieved at the fracture site. Pediatric bony structure has more elastic bones than that of adults, it can cause bowing deformity. Therefore, we evaluated pediatric tibial shaft fracture for the presence of bowing deformity, associated risk factors, and its clinical significance. HypothesisThere is an overlooked bowing deformity in pediatric tibial shaft fracture. Patients and methodsFifty-seven tibial shaft fracture patients aged 2 to 15 years with Risser stage 0 were retrospectively reviewed. Clinicoradiologic factors and radiographs taken within 3 post-traumatic months and at 2 years were assessed. To evaluate the tibial bowing deformity, the tibial interphyseal angle and tibial shaft angle were measured, and their differences were calculated as a tibial bowing angle. ResultsMultivariate analysis revealed the tibial shaft fracture with fibular involvement is significantly associated with a higher initial tibial bowing angle (valgus deformity). The tibial bowing angle did not change over 2-year follow-up. A high initial tibial bowing angle (≥ 5°) was a significant risk factor for the persistence of valgus malalignment. DiscussionPediatric tibial shaft fractures with/without fibular involvement carry the risk of valgus bowing deformity, which may not develop during post-traumatic growth but may be present at the time of injury. The risk is high if the tibial fracture is accompanied by a fibular fracture. This tibial deformity presents limited remodeling potential at 2-year follow-up. Level of evidenceIV; retrospective study.

The ankle in XLH: Reduced motion, power and quality of life.

X-linked hypophosphatemia (OMIM 307800) is a rare bone disease caused by a phosphate-wasting condition with lifelong clinical consequences. Those affected suffer from bone pain, complex skeletal deformities, impaired mobility and a reduced quality of life. Early osteoarthritis and reduced range of motion of the lower limbs are known pathologies in XLH patients. However, XLH-specific data on the affected compartments such as the ankle joint through the evaluation of radiographic and gait analysis data is still lacking. In this cross-sectional study, patients with genetically verified XLH, age ≥ 16 - 50 years and a complete record of gait analysis and or radiographic analysis data were included. Clinical examination, radiological and gait analysis data were compared to norms using the dataset of our gait laboratory registry. Radiographic analysis included tibial deformity analysis and assessment of osteoarthritis and enthesopathies. Western Ontario and McMaster Universities Arthritis Index (WOMAC), SF36v2, American Orthopedic Foot and Ankle Society score (AOFAS) and the Foot and Ankle Outcome Score (FAOS) were used. Twentythree participants with 46 limbs were eligible for the study. A total of 23 patients (n=46 feet) met the inclusion criteria. Patients with XLH had significantly reduced gait quality, ankle power and plantar flexion (p < 0.001) compared to a historic gait laboratory control group. Ankle valgus deformity was detected in 22 % and ankle varus deformity in 30 % of the patients. The subtalar joint (59.1%) as well as the anterior tibiotalar joint (31.1%) were the main localizations of moderate to severe joint space narrowing. Ankle power was decreased in moderate and severe subtalar joint space narrowing (p < 0.05) compared to normal subtalar joint space narrowing. No lateral or medial ligament instability of the ankle joint was found in clinical examination. Tibial procurvatum deformity led to lower ankle power (p < 0.05). This study showed structural and functional changes of the ankle in patients with XLH. Subtalar ankle osteoarthritis, patient reported outcome scores and clinical ankle restriction resulted in lower gait quality and ankle power.

Predicting Deformity Correction of Growth Modulation in Late-onset Tibia Vara.

Growth modulation in late-onset tibia vara (LOTV) has been reported to yield variable results. We hypothesized that parameters of deformity severity, skeletal maturity, and body weight could predict the odds of a successful outcome. A retrospective review of tension band growth modulation for LOTV (onset ≥8 y) was performed at 7 centers. Tibial/overall limb deformity and hip/knee physeal maturity were assessed on preoperative anteroposterior standing lower-extremity digital radiographs. Tibial deformity change with first-time lateral tibial tension band plating (first LTTBP) was assessed by medial proximal tibia angle (MPTA). Effects of a growth modulation series (GMS) on overall limb alignment were assessed by mechanical tibiofemoral angle (mTFA) and included changes from implant removal, revision, reimplantation, subsequent growth, and femoral procedures during the study period. The successful outcome was defined as radiographic resolution of varus deformity or valgus overcorrection. Patient demographics, characteristics, maturity, deformity, and implant selections were assessed as outcome predictors using multiple logistic regression. Fifty-four patients (76 limbs) had 84 LTTBP procedures and 29 femoral tension band procedures. For each 1-degree decrease in preoperative MPTA or 1-degree increase in preoperative mTFA the odds of their successful correction decreased by 26% in the first LTTBP and 6% by GMS, respectively, controlling for maturity. The change in odds of success for GMS assessed by mTFA was similar when controlling for weight. Closure of a proximal femoral physis decreased the odds of success for postoperative-MPTA by 91% with first LTTBP and for final-mTFA by 90% with GMS, controlling for preoperative deformity. Preoperative weight ≥100 kg decreased the odds of success for final-mTFA with GMS by 82%, controlling for preoperative mTFA. Age, sex, race/ethnicity, type of implant, and knee center peak value adjusted age (a method for bone age) were not predictive of outcome. Resolution of varus alignment in LOTV using first LTTBP and GMS, as quantified by MPTA and mTFA, respectively, is negatively impacted by deformity magnitude, hip physeal closure, and/or body weight ≥100 kg. The presented table, utilizing these variables, is helpful in the prediction of the outcome of the first LTTBP and GMS. Even if complete correction is not predicted, growth modulation may still be appropriate to reduce deformity in high-risk patients. Level III.

Is mid-sulcus line a predictive guide for tibial mechanical axis during total knee arthroplasty?

BackgroundAchieving appropriate alignment of components in total knee arthroplasty (TKA) is essential for optimal functional outcomes as well as implant longevity. Performing TKA in the absence of a computer-assisted navigation system (CANS) mandates the use of accurate anatomical landmarks for achieving appropriate alignment. In this study, we have evaluated the reliability of ‘mid-sulcus line’ as an anatomical landmark to guide tibial resection, with the intra-operative help of CANS. MethodA total of 322 patients undergoing primary TKA (excluding previously operated limbs and limbs with extra-articular deformities of tibia or femur) using CANS were included in the study. After resecting ACL, the mid-suclus line was drawn with a cautery tip. We hypothesized that if tibial cut was made perpendicular to the mid-sulcus line, coronal alignment of the tibial component would be along the neutral mechanical axis. This was evaluated intra-operatively with the help of CANS. ResultsOf 322 knees, identification of the ‘mid-sulcus line’ was possible in 312 knees. The mean angle between the tibial alignment defined by mid-sulcus line and the neutral mechanical axis was found to be 0.45° (range, 0–1.5°) (P < 0.05). In all of the 312 knees, the tibial alignment defined by mid-sulcus line was found to be within 3° of the neutral mechanical axis (confidence interval: 0.410°, 0.491°). ConclusionMid-sulcus line can be used as an additional anatomical landmark to guide the tibial resection and thereby achieve appropriate coronal alignment in primary TKAs without any extra-articular deformity.

Correcting Angular Limb Deformities of Radius-Ulna and Tibia in Nine Dogs Using Computer-Assisted Spider Frame System

Correcting Angular Limb Deformities of Radius-Ulna and Tibia in Nine Dogs Using Computer-Assisted Spider Frame System

Anatomical Imaging Study on Uneven Settlement of the Proximal Tibia.

Uneven settlement of the proximal tibia significantly contributes to the onset and progression of medial compartment knee OA; however, the specific location and variations of proximal tibial deformity remain unclear. Therefore, this study aimed to explore the effects of the anatomic morphology of different tibial regions on proximal tibial vara and proximal tibial microstructural changes with age in both sexes to reveal the pattern of uneven settlement of the proximal tibia. In this retrospective study, we reviewed the radiographs of 414 patients (789 legs) between May and September 2021. The medial proximal tibial angle (MPTA) and four anatomic angles of the tibia (i.e., the tibial plateau-epiphyseal line [PT-EL] angle, epiphyseal line-tibial platform [EL-PF] angle, epiphyseal axis inclination angle [EAIA], and subepiphyseal axis inclination angle [SAIA]) were measured. The effect of each angle on MPTA and their changes with age in both sexes were investigated using Pearson's correlation coefficient and multiple linear regression. In females, PT-EL angle, EL-PF angle, and SAIA negatively correlated with MPTA (r=-0.325, -0.246, and -0.502; p < 0.05), and EAIA positively correlated with MPTA (r=0.099, p < 0.05). Regression analysis showed that the correlations between MPTA and PT-EL angle, EL-PF angle, and SAIA were significant (β=-1.003, -0.013, and -0.971; adjusted R2 =0.979). Furthermore, MPTA negatively correlated with age (r=-0.202, p < 0.05); PT-EL angle and EAIA positively correlated with age (r=0.237 and 0.142, p < 0.05). Regression analysis showed that only the correlation between PT-EL angle and age was significant (β=5.635, p < 0.05). In males, PT-EL angle, EL-PF angle, and SAIA negatively correlated with MPTA (r=-0.270, -0.267, and -0.533; p < 0.05), and EAIA positively correlated with MPTA (r=0.135, p < 0.05). Regression analysis showed that the correlations between MPTA and PT-EL angle, EL-PF angle, and SAIA were significant (β=-0.992, -0.017, and -0.958; adjusted R2 =0.970). However, there was no significant correlation between age and any of the measured angles (p > 0.05). Proximal tibial vara is affected by the anatomic morphology of the epiphyseal and subepiphyseal regions. In females, the uneven settlement of the epiphysis progresses with age and may be responsible for dynamic varus deformity of the proximal tibia.

Correction of severe lower extremity deformity with digital hexapod external fixator based on CT data

PurposeOur goal was to examine the therapeutic effect of a self-designed digital six-axis external fixator technique for the correction of severe lower extremity deformities.Patients and methodsBetween January 2017 and December 2020, our institution employed self-developed digital hexapod external fixator technology (QSF), based on CT data, to gradually correct 28 severe tibial deformities, and 15 femurs underwent osteotomy and internal fixation. The mean patient age was 32.6 ± 14.3 years, and the mean follow-up duration was 27.4 ± 16.1 months. We also recoded and analyzed the values of preoperative and final follow-up MAD, mFTA, MPTA, LLD, mLDFA, LEFS, KSS, and functional score.ResultsThe QSF adjustment duration was 21.4 ± 10.8 days, and the healing duration of the tibial osteotomy site was 17.6 ± 7.0 weeks. The preoperative MAD, mFTA, and MPTA were 54.1 ± 26.2 mm, 167.7 ± 15.7°, and 75.2 ± 12.0°, respectively. At the last follow-up, the MAD was 8.2 ± 9.9 mm, mFTA was 177.6 ± 3.4°, and MPTA was 87.6 ± 2.4°. Based on these data, we achieved significant improvement post operation. The preoperative LLD and mLDFA values were 13.8 ± 18 mm and 83.7 ± 10.8°, respectively, and the values were 7.6 ± 7.6 mm and 87.8 ± 2.6°, respectively, at the last follow-up. This indicated no significant difference in these values before and after the operation. Finally, the LEFS, KSS, and functional scores improved from preoperative 51.6 ± 11.2, 68.5 ± 11.7, and 67.8 ± 11.2 to postoperative 72.3 ± 6.1, 92.9 ± 3.4, and 94.2 ± 6.3, respectively.ConclusionsBased on our analyses, the QSF technique accurately corrected severe multiplanar tibial deformities in adults. When combined with femoral osteotomy, satisfactory lower extremity alignment was obtained while correcting for femoral deformity. This technology has the advantages of simple operation, reliable fixation, less trauma, and less complications.

Tibia Multiplanar Deformities and Growth Disturbance Following Expandable Endoprosthetic Distal Femur Replacement.

Expandable distal femur endoprosthesis (EDFE) is commonly used to compensate for the loss of the distal femoral epiphyseal plate in skeletally immature children who have undergone surgical resection of bone malignancies. However, the effect of the passive tibial component of the EDFE on tibial growth has not been extensively studied in the literature. This study aims to delineate the type, frequency, and associated risk factors of multiplanar proximal tibial deformities in skeletally immature children following the use of the expandable distal femur endoprosthesis (EDFE). Moreover, we plan to detect how these deformities influence the long-term functionality of the endoprosthesis in defining the need for subsequent implant revision or further surgical management. A total of 20 patients aged (7-12) years underwent expandable distal femur replacement. Two types of implants were used: Juvenile Tumor System (JTS) non-invasive prosthesis in 14 patients, and Modular Universal Tumor and Revision System (MUTARS)® Xpand Growing Prostheses in six patients. A scanogram and CT scan documented the measurements of longitudinal and multiplanar growth as leg length discrepancy (LLD), femur length discrepancy (FLD), tibia length discrepancy (TLD), and the yield values of rotational, sagittal, and coronal deformities of the tibia. The patients were followed up to assess the need for further management. Sex, age, size of tibial plate perforation, and type of implant used were studied for possible correlation with deformities or growth disturbance. The patients were followed up for a mean of 3 (2-7) years. A total of 14 patients, (10 JTS, 4 implant cast) had a tibial deformity and/or growth disturbance. A single patient was found to have all deformities (growth, rotational, coronal, and sagittal). Fourteen patients were found to have an LLD ranging from 5.3 to 59 mm (median 21 mm), 12 had a TLD from 3 to 30 mm, (median 10 mm), and 11 patients showed evidence of malrotation from 6 to 32 degrees (median 11 degrees). TLD was found to contribute entirely to LLD in three patients, and &gt;50% of LLDs in seven patients. All LLDs were treated conservatively, except in three patients; two received contralateral tibia epiphysiodesis and one received revision with a new implant. A single patient had a posterior tibia slope angle (PTSA) of -2.8 degrees, and three patients had a coronal deformity with a mean medial proximal tibia angle (MPTA) of 80.3 (77-83 degrees). Tibial growth disturbance and multiplanar deformities occur in the majority of patients following EDFE replacement, exacerbating LLD. Yet, these disturbances may be well tolerated, managed conservatively, and rarely mandate endoprosthetic revision or subsequent corrective surgery. Age at the time of surgery was found to be the only significant contributor to the development of tibia growth disturbance.

Results of Wedgeless Distal Femoral Osteotomy for the Treatment of Genu Valgus Deformity.

Coronal plane knee deformities are common disorders affecting adolescents. Valgus deformities (tibiofemoral angle (TFA) > 12-15 degrees and intermalleolar distance (IMD) > 10 cm) often require corrective osteotomy and a wedgeless "V" distal femoral osteotomy is a good treatment option for such deformities. Thirty adolescent patients (13-17 years) with valgus deformitieswere included. Patients with severe collateral ligament instability, subluxation, and sagittal plane deformity > 15 degrees or genu valgum due to tibial deformity were excluded. Preoperativeclinical(Bostman's knee score, IMD, and knee-flexion test) and radiological evaluations weredone. The surgery (wedgeless distal femoral V osteotomy) was performedand stabilized with two Kirschner wires (K-wires). Postoperative clinical and radiological parameters were recorded including complications. The preoperative TFA was 20.23 ± 3.63 degrees, which reduced to 5.5 ± 0.73 at six months postoperatively. The preoperative IMD was 12.45 ± 2.2 cm, which reduced to 1.63 ± 0.32 cm at six months. The mean mechanical axis deviation (MAD) and lateral distal femoral angle (LDFA)were recorded as 2.8 ± 0.39 and 87.7 ± 0.83, respectively, and the differences were statistically significant from preoperative values. The Bostman score was 26.2 ± 1.79 at three months and 29.47 ± 0.9 at six months. The complications included infection in two patients, a hypertrophic scar in one patient, and common peroneal neuropraxia in one patient. Wedgeless distal femoral osteotomywith K-wire fixation is a viable option for correction of genu valgus deformity with potential advantages of minimal blood loss, no leg length discrepancy, non-rigid fixation, and early union as compared to other treatment options.