Hemiepiphysiodesis for Lower Extremity Coronal Plane Angular Correction in the Distal Femur and Proximal Tibia in Children With Achondroplasia.

BACKGROUND: Achondroplasia is the most prevalent form of skeletal dysplasia, affecting more than 250,000 individuals. Lower extremity angular deformities, particularly genu varum, are common in children with achondroplasia, often resulting in pain and limitation of function. The authors aim to determine the utility of lower extremity growth modulation with hemiepiphysiodesis in children with achondroplasia for correction of coronal plane deformities about the knee. METHODS: The authors performed a retrospective chart review of a single center from 1/1/2000 to 12/31/2020 to identify pediatric patients with achondroplasia treated with hemiepiphysiodesis as their initial procedure at the distal femur and/or proximal tibia. Patients with adequate records and who had completed their treatment were included. Data collected included duration of treatment, complications, need for osteotomy, and radiographic measurements including initial and final mechanical axis deviation, knee mechanical axis zone, mechanical lateral distal femoral angle and medial proximal tibia angle. RESULTS: Ten patients with 17 limbs met our criteria. Nine patients (15 limbs) were treated for genu varum and 1 patient (2 limbs) was treated for genu valgum. Prior to treatment, the mechanical axis fell in zone 3 in 59% of limbs and zone 2 in 41%. Average correction in mechanical axis deviation was 26.1 mm. Average change in mechanical lateral distal femoral angle was 10.3 degrees per limb, and average change in medial proximal tibia angle was 7.1 degrees per limb. Average treatment duration was 909 days. At final follow up, 81% (14/17) of limbs had the mechanical axis in zone 1, with the remaining 18% (3/17) in zone 2. No patient/limb underwent subsequent distal femur or proximal tibia osteotomy for coronal plane alignment. CONCLUSIONS: Children with achondroplasia can successfully be treated with hemiepiphysiodesis to correct coronal plane deformities at the distal femur and proximal tibia. Using this technique, no patient in our series required an osteotomy for genu varum/valgum. LEVEL OF EVIDENCE: Therapeutic level IV, Case series.

Pitfalls in the Diagnosis of Primary Hyperparathyroidism in a Sudanese Adolescent Boy; a case disguised as rickets.

BACKGROUND: Juvenile primary hyperparathyroidism (PHPT) is a rare endocrine disease. Its diagnosis might be masked by clinical, biochemical, and radiological features of rickets. CASE PRESENTATION: A 12-year-old Sudanese boy presented with progressive lower limbs deformity and difficulty in walking for six months. It was associated with fatigability, poor appetite, and generalized bone pain. On examination, he was thin, disproportionately short and pubertal, and had bilateral genu valgum deformity. X-rays showed osteopenia and signs of rickets. Biochemical workup revealed mildly elevated serum calcium, low phosphate, high alkaline phosphatase, and high parathyroid hormone with low 25-hydroxy vitamin D3. Celiac screening, liver function test and renal profile were normal. Serum calcium rose dramatically after vitamin D therapy. Genetic testing was negative for CYP2R1 and MEN1 genes. Ultrasound neck showed left inferior parathyroid adenoma which was surgically excised. Histopathology confirmed the diagnosis of parathyroid adenoma. Postoperatively, he had hypocalcemia which was treated with calcium and alfacalcidol. Corrective surgery is planned for the genu valgum deformity which markedly improved after parathyroidectomy. CONCLUSION: Although PHPT is extremely rare in the young population, it should be considered in patients with rickets and elevated serum calcium at baseline or after initiating vitamin D therapy.

Genu Valgum After Distal Femur Extension Osteotomy in Children With Cerebral Palsy.

BACKGROUND: Distal femur extension osteotomy (DFEO) is a common treatment for knee flexion contracture and crouch gait in patients with cerebral palsy (CP), but skeletally immature patients tend to develop genu valgum deformities after DFEO. This study aimed to report the tendency of valgus changes after DFEO and determine the risk factors for subsequent surgery for excessive genu valgum. METHODS: This retrospective case-control study included 25 children with CP who underwent DFEO in 44 limbs for knee flexion contractures ≥15 degrees at a mean age of 11.0 years. Radiologic measurements included the anatomic lateral distal femoral angle (aLDFA), anatomic tibiofemoral angle (aTFA), medial proximal tibia angle, and plate-condyle angle, postoperatively and at the latest follow-up. Age, sex, preoperative knee flexion contracture angle, Gross Motor Function Classification System level, and radiographic measurements were compared between children with and without subsequent guided growth for genu valgum. RESULTS: A significant valgus change was observed at the distal femur in the first postoperative year (aLDFA from 83.6 to 80.1 degrees, P<0.001; aTFA from 176.1 to 172.5 degrees, P<0.01; plate-condylar angle from 5.3 to 9.5 degrees, P<0.001). Valgus changes occurred in 36 of the 44 limbs (82%) by an average of -4.6 degrees in the aLDFA, and subsequent guided growth was performed in 5 patients (20%). Guided growth for genu valgum was associated with a greater postoperative valgus angle (aLDFA: 78.0 vs. 84.9 degrees, P<0.01) but not with age, Gross Motor Function Classification System level, or preoperative flexion contracture. CONCLUSIONS: Distal metaphyseal osteotomies and distally placed angled plates near the physis are associated with valgus changes following growth. We recommend making a slight varus alignment during DFEO to compensate for subsequent valgus changes. LEVEL OF EVIDENCE: Level III-therapeutic, retrospective comparative study.

Treatment of genu valgum by a novel percutaneous transverse metaphyseal osteotomy of the distal femur in children and adolescents.

PURPOSE: To evaluate the outcomes of a novel percutaneous medial supracondylar femoral osteotomy and above-knee cast technique in children and adolescents as a minimally invasive surgical intervention for treatment of genu valgum. METHODS: In this prospective study, 60 patients (70 knees) with a tibiofemoral angle more than 15° were treated with a novel medial percutaneous supracondylar femoral osteotomy and above-knee cast and followed up for an average of 29 months. The radiological outcome was measured with MAD, TFA, and mLDFA. The functional outcome was evaluated by a modified Böstman score. RESULTS: The preoperative mean MAD, TFA, and mLDFA were 2.9 cm, 16.3°, and 79.2° respectively. The Böstman score averaged preoperatively 23.1. There was a significant improvement of all radiological and clinical outcome measures (P < 0.001). Per Böstman score, 2 knees in one patient (3%) showed an unsatisfactory result, while 14 (20%) and 54 (77%) knees had a good or excellent result, respectively. Two patients (three limbs) needed early re-casting. Other complications were not encountered. CONCLUSION: In experienced hands, percutaneous transverse metaphyseal femoral osteotomy and above-knee casting appear to be a safe, supracondylar cost-effective, and reliable minimally invasive acute correction technique in genu valgum in children and adolescents. LEVEL OF EVIDENCE: Level IV-therapeutic.

Common peroneal nerve 'pre-release' in total knee arthroplasty for severe valgus deformities.

BACKGROUND: Common peroneal nerve (CPN) palsy is a devastating complication that follows total knee arthroplasty (TKA). However, there are only a few studies on concrete measures for protecting the CPN in patients. This study aimed to put forward the CPN 'pre-release' method to protect the nerve. METHODS: A prospective study was conducted on 30 patients (34 knees) with severe valgus knees who underwent CPN pre-release. This was a two-incision approach, and required a separate dissection of about three centimeters from the TKA operation. Clinical measurements including pre- and postoperative motor and sensory nerve function of CPN, radiological evaluation, complications, and the revised data were analyzed and compared. RESULTS: The average preoperative femorotibial angle was 31.3 ± 8.0°. All patients had completely normal motor (grade 5) and sensory nerve function of CPN postoperatively, and there was no transient or late-onset CPN palsy. Patients had a routine rehabilitation with full weight bearing after recovery from anesthesia, including the knees with unconstrained extension/flexion motion. During the last follow-up visit, the visual analog scale, Knee Society Score, Hospital for Special Surgery knee-rating scale, and range of motion were 2.06 ± 1.13, 92.18 ± 5.57, 90.18 ± 3.70, and 115.59 ± 7.76°, respectively. There were no revisions for instability and recurrent valgus deformities during follow-up. Also, the femorotibial angle, hip-knee-ankle angle, condylar-hip angle, and plateau-ankle angle were 4.9 ± 2.0°, 179.09 ± 3.21°, 89.97 ± 2.41°, and 90.53 ± 1.26°, respectively. CONCLUSIONS: The CPN pre-release for severe valgus knees is an effective method for nerve protection, achieving an adequate and safe release of lateral soft tissue, and providing immediate and early functional rehabilitation with decreasing constrained implant.

The Outcomes of Distal Femoral Varus Osteotomy in Patellofemoral Instability: A Systematic Review and Meta-Analysis.

Distal femoral varus osteotomies have been novelly described in the recent years to be successful in the management of patellofemoral instability with genu valgum. However, these publications are limited to case reports and small case series and no published literature have attempted to analyze them in totality. The current review aims to pool together these small case series to evaluate the outcomes and complications of distal varus femoral osteotomies when performed for patellofemoral instability. The review was conducted using the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. All studies that reported the outcomes of distal femoral varus osteotomy for patellofemoral instability were included. A total of five publications were included in the review, which included a total of 73 patients. All of the studies reported improvement in the radiological outcomes for genu valgum correction and patellofemoral instability. One study using opening wedge osteotomy reported a decrease in Caton-Deschamps index postoperatively, while another study using closing wedge osteotomy reported maintenance of the Caton-Deschamps index postoperatively. Second look arthroscopy showed an improvement in the status of the chondral lesions of the medial facet of the patellar undersurface, the lateral facet of the patellar undersurface and the trochlear groove 2 years postoperatively. All studies also reported a decrease in the risk of recurrence of patellofemoral instability, reduction in pain, and an improvement in all the clinical outcomes knee scores. Distal femoral varus osteotomy is promising and useful in the management of patellofemoral instability with genu valgum. The procedure can allow for radiological correction of the genu valgum and patellofemoral instability, reduction in the risk of recurrence of patellofemoral instability, reduction in pain, improvement in clinical knee outcome scores, and improvement in the status of the chondral lesions in the patellofemoral joint. It is highly versatile and could accommodate varying degrees of correction. These improvements in radiological and clinical outcomes can be seen in studies for both closing wedge and opening wedge distal femoral osteotomies. However, opening wedge osteotomies appear to decrease the patellar height as compared with closing wedge osteotomies which maintain the patellar height; therefore, the patellar height should be assessed preoperatively prior to deciding whether to perform an opening wedge or closing wedge distal femoral varus osteotomy. The Level of Evidence for this study is IV.

Total Knee Arthroplasty for Fixed Valgus Deformity Correction Using a Modified Lateral Parapatellar Approach.

Total knee arthroplasty (TKA) for patients with valgus deformity (> 10 degrees) is technically challenging and has produced variable clinical results in terms of deformity correction, instability, and overall outcomes. The lateral parapatellar approach (LPA) is an alternative to the traditional medial parapatellar approach with potential advantages of direct access for release of tight lateral ligamentous structures with preservation of the medial structures, optimized patellar tracking, preserved medial blood supply to the patella, and less use of constrained implants. We present a case series of a single institution's experience with use of a modified LPA using a Z-capsuloplasty for 35 primary TKA cases in 30 patients with osteoarthritis and Ranawat's type-II fixed valgus deformity with attenuation of medial soft tissues. The mean age of patients was 64.8 years (range: 42-78 years). Follow-up duration was a mean of 47.3 months (range: 3-130 months). The patients were assessed pre- and postoperatively using radiographic measurement of the anatomic femorotibial angle (FTA) and clinical measurement of range of motion (ROM) and the Chinese knee society score (KSS). Complications and reoperations were recorded. The mean coronal alignment was corrected from 20.4 degrees of valgus (range: 11.3-42 degrees) preoperatively to 7.0 degrees of valgus (range: 3.6-15.1 degrees) postoperatively. One case required use of a constrained condylar design implant. At a mean of 47.3 months, the mean Knee Society objective and functional scores improved to 91.8 ± 6.6 and 84.3 ± 18.2 points, respectively. Mean ROM was 94.9 degrees preoperatively and 105.7 degrees postoperatively. Three cases (8.6%) had postoperative complications, including transient common peroneal nerve palsy, hematoma, and deep infection. One patient underwent two-stage revision for infection. There were no cases of late instability. The modified LPA using a Z-capsuloplasty is a reproducible and effective surgical technique for performing TKA in the setting of osteoarthritis and severe valgus deformity.

Tibial bowing and tibial component placement in primary total knee arthroplasty in valgus knees: Are we overlooking?

PURPOSE: Tibial bowing in valgus knees with arthritis can lead to component malplacement during total knee arthroplasty (TKA). Incidence of valgus knees with medial tibial bowing, its effect on tibial component placement during primary TKA and methods to improve accuracy of the component placement were studied. METHODS: Full-length weight-bearing alignment radiograph was taken in 117 patients (149 knees) with valgus deformity undergoing TKA. In these cases, the proximal tibial reference for extramedullary jig placement was planned preoperatively with reference to the tibial spines and classified as four zones. RESULTS: The mean preoperative hip-knee-ankle (HKA) angle was 192.9° (180.3-234.5°). Bowing >3° was considered significant (p < 0.001) and at this level of bowing, the proximal tibial reference was shifted from centre to medial. Tibial bowing <3° was considered straight and >3° as tibia valga. Tibia was bowed in 70 knees (46.97%). Severity of valgus deformity had strong positive correlation with the tibia valga (p < 0.001). The post-operative medial proximal tibial angle (MPTA) and HKA angle were 91.63° (87.9-95.7°) and 182.6° (178.1-189.7°), respectively. The mean MPTA and post-operative HKA angle in bowed and straight tibiae were 90.35° versus 89.78° (p = 0.547) and 181.5° versus 180.7° (p = 0.5716), respectively, and the difference was not statistically significant. CONCLUSION: Medial tibial bowing is very common in valgus knees. Tibia valga has a strong positive correlation with the severity of valgus deformity. Accurate tibial component placement can be achieved with a medialized reference point for extramedullary tibial cutting jig in knees with significant tibia valga. The study has been registered in clinical trials registry - India (CTRI/2018/03/012283).

Same-stage total knee arthroplasty and osteotomy for osteoarthritis with extra-articular deformity. Part II: Femoral osteotomy, prospective study of 6 cases.

BACKGROUND: Same-stage (1S) total knee arthroplasty (TKA) and femoral osteotomy (FO) may deserve consideration in patients with both knee osteoarthritis and severe extra-articular knee deformity (EKD). The objective of this study was to assess clinical and radiological outcomes and morbidity (complications and revisions) in 6 patients managed with S1-TKA-FO. HYPOTHESIS: 1S-TKA-FO produces satisfactory outcomes and is not associated with higher morbidity rates compared to two-stage TKA-TO or TKA with intra-articular EKD correction, while also significantly shortening total treatment duration. MATERIAL AND METHODS: A prospective study was performed in 6 patients managed with 1S-TKA-FO between 1999 and 2011; mean age was 64 years (range, 59-72 years) and mean body mass index was 29.5 (range, 26-35). The EKD was consistently greater than 10°. The cause was post-traumatic mal-union in 4 patients, constitutional EKD in 1 patient, and FO in 1 patient. In each patient, the clinical International Knee Society (IKS) score and the hip-knee-ankle angle (HKA), femoral mechanical angle (FMA) and tibial mechanical angle (TMA), were recorded prospectively before and after surgery. RESULTS: A long uncemented extension stem was used in all 6 patients and a posterior-stabilised implant in 5 patients. No hinged implants were used. In 4 patients, internal fixation of the FO was performed. Mean follow-up was 10 years (range, 4-15 years). From baseline to last follow-up, the mean IKS score increased from 46 to 161 and mean flexion from 95° (range, 70-110°) to 107° (range, 90-120°). The HKA measured radiographically was between 178° and 182° in all 6 patients. The complications consisted of deep vein thrombosis in 1 patient and knee stiffness requiring manipulation under general anaesthesia in 1 patient. No patient experienced mal-union or required revision surgery. DISCUSSION: Apart from a case-series study of 11 patients, very few data are available on 1S-TKA-FO. In our small population, no major complications were recorded. The encouraging long-term outcomes warrant a recommendation to perform 1S-TKA-FO in patients with knee osteoarthritis and an intra-femoral deformity greater than 10°. LEVEL OF EVIDENCE: IV, prospective observational cohort study.

Same-stage total knee arthroplasty and osteotomy for osteoarthritis with extra-articular deformity. Part I: Tibial osteotomy, prospective study of 26 cases.

BACKGROUND: In patients with advanced knee osteoarthritis and extra-articular knee deformity (EKD), ligament balance may be difficult to achieve during total knee arthroplasty (TKA). Treatment options include two-stage surgery with the first stage involving correction of the EKD and same-stage TKA and tibial osteotomy (1S-TKA-TO). The objective of this study was to assess outcomes in 26 patients managed with 1S-TKA-TO. HYPOTHESIS: 1S-TKA-TO produces satisfactory clinical and anatomical outcomes and is not associated with higher morbidity rates compared to TKA alone or two-stage TKA-TO. MATERIAL AND METHODS: A prospective study was conducted in 25 patients (26 knees) managed with 1S-TKA-TO between 1995 and 2014. There were 16 males and 9 females with a mean age of 64 years (range, 29-80 years) and a mean body mass index of 29.6 (range, 24-49). The EKD was constitutional in 14 knees, post-traumatic in 5 knees, and induced by TO in 7 knees. None of the patients received a hinged knee implant. In each patient, the clinical International Knee Society (IKS score) was assessed and the hip-knee-ankle angle (HKA), tibial mechanical angle (TMA), and femoral mechanical angle (FMA) were measured on radiographs before surgery and at last follow-up. RESULTS: The mean IKS score increased significantly, from 70 before surgery to 170 at the end of the mean 9-year follow-up. Mean flexion range increased from 98° to 107°. The clinical and anatomical outcomes were satisfactory in 25 patients. In the remaining patient, who had a history of multiple surgeries for Blount disease and a body mass index of 49, a severe complication consisting in massive skin necrosis followed by infection occurred; this was the only patient who required revision surgery with implant removal. DISCUSSION: These findings are consistent with the satisfactory outcomes observed in earlier studies, most of which included small numbers of patients. The alternatives to 1S-TKA-TO are under evaluation. The best indication for 1S-TKA-TO may be knee osteoarthritis with a greater than 10° intra-osseous deformity. LEVEL OF EVIDENCE: IV, prospective observational cohort study.

Total Knee Arthroplasty in Severe Valgus Deformity Using a Modified Technique-A 10-Year Follow-Up Study.

BACKGROUND: Valgus knee deformity accounts for only 10% of total knee arthroplasties (TKAs), but is frequently considered the most challenging to manage. This study provides a 10-year follow-up on a previously reported series of severe valgus knees performed using an unconstrained mobile-bearing TKA with a modified technique to validate this technique. METHODS: A consecutive series of 275 predominantly cementless TKAs in 262 patients were performed for severe valgus (≥10°) deformity and prospectively followed to 10 years. Patient-reported outcome measures included the Oxford Knee Score, American Knee Society Score, Bartlett Patellar Score, and the Short Form 12 questionnaire. RESULTS: Average valgus deformity was reduced from 15.6° to 3.8° (P < .001). At a mean follow-up of 10.4 years (range, 9.5-14.1), 90 (34.4%) patients had died. Of the reviewed survivors, the mean Oxford Knee Score was 27.8 ± 9.8, with an American Knee Society clinical score of 85.6 ± 17.0 and a functional score of 65.1 ± 20.4, with 78% of patients reporting good to excellent results. To date, there has been 1 (0.36%) revision and 13 (4.73%) reoperations. Kaplan-Meier implant survival was 99.6% at 10 years. CONCLUSION: Despite its challenging nature, the valgus knee is associated with excellent survivorship and satisfactory long-term results using this modified technique. LEVEL OF EVIDENCE: Level IV.

Surgical Treatment With Closing-Wedge Distal Femoral Osteotomy for Recurrent Patellar Dislocation With Genu Valgum.

BACKGROUND: Closing-wedge distal femoral osteotomy (CWDFO)-combined with medial reefing and lateral release, if necessary- has been used to treat recurrent patellar dislocation (RPD) with genu valgum. PURPOSE: To evaluate the clinical and radiologic outcomes of surgical treatment with CWDFO for treatment of RPD with genu valgum. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Fourteen consecutive patients (23 knees) with RPD and genu valgum were treated with CWDFO. Patients with a minimum 2-year follow-up period were eligible for this study. Patients with prior failed surgery were also eligible. Radiographic evaluation was performed with mechanical femorotibial and lateral distal femoral angle. The radiographic parameters presenting patellar positions and pathologic abnormalities associated with RPD were evaluated. Chondral lesion changes in second-look arthroscopic examination were examined, and clinical outcomes (eg, occurrence of redislocation, range of motion, and clinical scores) were assessed pre- and postoperatively at a minimum of 2 years. RESULTS: At a mean follow-up of 30.7 months (range, 25-62 months), the mean mechanical femorotibial and mechanical lateral distal femoral angles changed significantly from valgus 5° (range, 2°-11°) to varus 3° (2°-11°; P < .001) and from 83° (range, 78°-86°) to 89° (84°-92°; P < .001), respectively. The mean patellar congruence angle improved from 40° lateral (range, 20°-53° lateral) to 4° medial (23° medial to 21° lateral; P < .001), as did the lateral patellofemoral angle from 26° (range, 8°-62°) to 9° (0°-15°; P < .001). Computed tomography scans showed that the mean distance of patellar lateral shift decreased from 13.5 mm (range, 4-22 mm) to 2.0 mm (-4 to 5 mm; P < .001). The mean tibial tubercle to trochlear groove distance significantly decreased from 20.4 to 13.5 mm ( P < .001), while the Caton-Deschamps ratio did not change significantly after surgery ( P = .984). Chondral lesions of the patella and trochlear groove significantly improved or were maintained. None of the patients experienced subluxation or redislocation after surgery. Patellar instability symptoms also improved, as validated by radiographic and other clinical outcomes. CONCLUSION: CWDFO combined with medial reefing and lateral release successfully treated RPD with genu valgum for a minimum follow-up of 2 years, with improved patellar alignment and stability.

Two-dimensional motion analysis of dynamic knee valgus identifies female high school athletes at risk of non-contact anterior cruciate ligament injury.

PURPOSE: Female athletes are at greater risk of non-contact ACL injury. Three-dimensional kinematic analyses have shown that at-risk female athletes have a greater knee valgus angle during drop jumping. The purpose of this study was to evaluate the relationship between knee valgus angle and non-contact ACL injury in young female athletes using coronal-plane two-dimensional (2D) kinematic analyses of single-leg landing. METHODS: Two hundred ninety-one female high school athletes newly enrolled in basketball and handball clubs were assessed. Dynamic knee valgus was analysed during single-leg drop jumps using 2D coronal images at hallux-ground contact and at maximal knee valgus. All subjects were followed up for 3 years for ACL injury. Twenty-eight (9.6%) of 291 athletes had ACL rupture, including 27 non-contact ACL injuries. The injured group of 27 knees with non-contact ACL injury was compared with a control group of 27 randomly selected uninjured knees. The relationship between initial 2D movement analysis results and subsequent ACL injury was investigated. RESULTS: Dynamic knee valgus was significantly greater in the injured group compared to the control group at hallux-ground contact (2.1 ± 2.4 vs. 0.4 ± 2.2 cm, P = 0.006) and at maximal knee valgus (8.3 ± 4.3 vs. 5.1 ± 4.1 cm, P = 0.007). CONCLUSION: The results of this study confirm that dynamic knee valgus is a potential risk factor for non-contact ACL injury in female high school athletes. Fully understanding the risk factors that increase dynamic knee valgus will help in designing more appropriate training and interventional strategies to prevent injuries in at-risk athletes. LEVEL OF EVIDENCE: Prognostic studies, Level II.

Patellofemoral dysbalance and genua valga: outcome after femoral varisation osteotomies.

INTRODUCTION: Patellofemoral dysbalance may be caused by trochlear dysplasia, an elevated TTTG distance, femoral or tibial torsional deformities, patella alta, or a genu valgum. The surgical procedure for the treatment of a genu valgum is varisation osteotomy, usually in the femoral aspect. Several authors believe that a genu valgum is one cause of patellofemoral dysbalance, but studies about the outcome of the treatment with a varisation osteotomy are rare. MATERIALS AND METHODS: Nineteen knees in 18 patients, aged on average 28 (16-52) years were investigated in a retrospective study. The patients had symptoms of patellofemoral instability or anterior knee pain due to a genu valgum, without symptoms of a lateral femorotibial compartment. All patients underwent a femoral varisation osteotomy. The diagnostic investigation prior to surgery included full-leg radiographs and torsional angle CT scans. The pre-surgery and follow-up investigation included the visual analog scale (VAS), the Kujala score, the Japanese Knee Society score, the Lysholm score. RESULTS: The mean duration of follow-up was 44(10-132) months. The mean preoperative mechanical valgus was 5.6° (range 4-10°). Twelve patients mentioned patellar instability as the main symptom while 14 mentioned anterior knee pain. No redislocation occurred in the follow-up period. Anterior knee pain on the VAS (p value < 0.001) was significantly reduced (5.6-2.1). The Japanese Knee Society score improved from 87 to 93 (p value 0.013) points, the Kujala score improved significantly from 72 to 87 (p value 0.009), and the Lysholm score significantly from 76 to 92 (p value < 0.001). CONCLUSION: Genua valga can lead to patellofemoral dysbalance, treatment of this condition is femoral varisation osteotomy. In this study, patellofemoral stability was achieved and anterior knee pain was significantly reduced. Significant improvements in clinical scores proved the success of the treatment. LEVEL OF EVIDENCE: IV, case series.

Prevalência de genuvalgo em escolas públicas do ensino fundamental na cidade de santos (sp), brasil / Prevalence of genu valgum in public elementary schools in the city of santos (sp), brazil

RESUMO Objetivo: Avaliar a prevalência de genuvalgo e fatores associados em alunos do ensino fundamental. Métodos: Estudo transversal, realizado em 2015, com 1.050 crianças e adolescentes matriculados no ensino fundamental de Santos. Foi avaliado o desalinhamento do joelho, medindo-se a distância intermaleolar, considerada se ≥≥8 cm ou <8 cm. O coeficiente Kappa de 0,94 foi obtido para aferir a confiabilidade dos exames entre os avaliadores. O estado nutricional foi verificado segundo a Organização Mundial de Saúde, 2006. Aplicou-se modelo de regressão logística para avaliar fatores associados à presença de genuvalgo. Resultados: Dos escolares analisados, 7,1% apresentaram genuvalgo. Aqueles com sobrepeso ou obesos apresentaram porcentagens maiores de genuvalgo. Em média, os estudantes com genuvalgo são mais velhos do que aqueles sem genuvalgo. Não foi verificada associação com o sexo. No modelo de regressão logística, apenas a avaliação nutricional permaneceu significantemente associada à presença de genuvalgo. A chance de sua ocorrência em escolares com sobrepeso e obesos é, respectivamente, 6,0 e 75,7 vezes maior que a chance de ocorrência em magros ou eutróficos. Conclusões: A prevalência de genuvalgo em crianças e adolescentes do ensino fundamental da rede municipal de Santos foi de 7,1%, sendo maior nos alunos com sobrepeso/obesos, não apresentando associação com o sexo ou a idade.

ABSTRACT Objective: To evaluate the prevalence of genu valgum and associated factors in elementary school students. Methods: Cross-sectional study, carried out in 2015, with 1,050 children and adolescents enrolled in an elementary school in Santos, Southeast Brazil. Misalignment of the knee was assessed by intermalleolar distance, considering ≥8 cm or <8 cm. Inter-examiners reliability was measured by Kappa coefficient, resulting in 0.94. Nutritional status was evaluated according to the World Health Organization 2006 references. Logistic regression model was applied to analyze variables associated with genu valgum. Results: Among schoolchildren, 7.1% had genu valgum. The frequency was higher among overweight or obese schoolchildren. On average, students with genu valgum are older than those without it. There was no association with gender. Upon logistic regression model, only nutritional status was significantly associated with this condition. The chance of occurrence of valgus knee in overweight and obese schoolchildren was, respectively, 6.0 and 75.7 times greater than among thin or eutrophic subjects. Conclusions: The prevalence of genu valgum in elementary school children and adolescents was 7.1%, being higher among overweight/obese students and presenting no association with gender or age.

Individual valgus correction angle improves accuracy of postoperative limb alignment restoration after total knee arthroplasty.

PURPOSE: The purpose of the current study was to compare and investigate the effect of fixed and individual valgus correction angle (VCA) on postoperative alignment restoration. It is hypothesized that individual VCA would be more accurate than fixed VCA in postoperative limb alignment restoration. METHODS: Four hundred and fifty-two patients with 546 consecutive uncomplicated primary total knee arthroplasties performed by a single surgeon, with 302 knees that had individual VCA (group A) and 244 knees that had fixed 5° VCA (group B), were enroled in this study. Preoperative and postoperative full-length standing hip-to-ankle radiographs were used to assess limb alignment. Postoperative hip-knee-ankle angle (θ), femoral component angle (α) and tibial component angle (ß) were measured and compared between the two groups. RESULTS: Mean postoperative θ angle and α angle were 178.9° (SD 1.3°) and 89.1° (SD 1.1°) in the group A, whereas they were 177.8° (SD 1.9°) and 87.9° (SD 1.5°) in the group B. There were significant differences in both parameters between the two groups (p = 0.021 and 0.016, respectively). Mean postoperative ß was 89.8° (SD 1.2°) in the group A and 89.7° (SD 1.3°) in the group B, and no significant difference was detected. There were 114 (37.7 %), 221 (73.2 %) and 265 (87.7 %) knees that had restoration of mechanical axis to ±1°, ±2°, ±3° of neutral, respectively, and 37 (12.3 %) outliers (>±3°) in the group A, whereas there were 48 (19.7 %), 122 (50.0 %) and 170 (69.7 %) knees that had restoration of mechanical axis to ±1°, ±2°, ±3° of neutral, respectively, and 74 (30.3 %) outliers in the group B. Group A had a higher percentage of restoration of limb alignment and fewer outliers than those in the group B, and this difference was statistically significant (p < 0.001). CONCLUSIONS: The results from the present study demonstrated that individual VCA for distal femoral resection could enhance the accuracy of postoperative limb alignment restoration compared with fixed VCA. For clinical relevance, individual VCA should be recommended for routine use in all patients in order to achieve the expected postoperative neutral limb alignment and reduce the risk of postoperative malalignment due to the planning error of a fixed VCA. LEVEL OF EVIDENCE: Prospective comparative study, Level II.

Corrective osteotomy with retrograde Fassier-Duval nail in an osteogenesis imperfecta patient with bilateral genu valgum: A case report.

RATIONALE: The treatment of osteogenesis imperfecta (OI) requires a multidisciplinary approach to maximize function and reduce fracture incidence. The aim of this case report was to discuss an alternative surgical approach to stabilize a corrective osteotomy using the Fassier Duval (FD) system in an OI patient. PATIENT CONCERNS: A 20-year-old OI woman presented with left thigh pain, gait disturbance, and bilateral genu valgus deformities. DIAGNOSES: Physical examination and standing radiographs revealed bilateral genu valgum with previous fixation implants in the femoral and the left tibia. INTERVENTIONS: Staged surgery was performed. A previous Ender pin was removed from the left femur, and a FD nail was inserted in a retrograde fashion. An intercondylar fracture was encountered while inserting the female rod in the distal left femur. After removal of a previous Rush pin from the right femur, several complications were also encountered during FD nailing of the right femur. The tip threads of the FD male nail could not achieve adequate anchorage in the region of the greater trochanter. To prevent male nail dropping, a horizontal stop Kirschner pin was inserted close to the distal end of the female nail. OUTCOME: Despite perioperative problems such as rod dropping and occurrence of an intercondylar fracture of the left distal femur, bilateral retrograde nailing using the FD system was successful. An accurate entry portal is important when performing retrograde rodding. In addition, reaming the portal to a larger diameter in order to accommodate the large head of the female nail can prevent intraoperative intercondylar split, especially when combined with an osteotomy at the distal femur. LESSONS: Selection of the proper surgical technique is dependent on both the surgeon's experience and the condition of the patient. Although not an optimal device, a FD nail can be used as an IM nail for corrective osteotomy at the distal femur in an adult OI patient with a small femoral IM canal.

Decreased extension gap and valgus alignment after implantation of total knee prosthesis in primary varus knees.

PURPOSE: It was hypothesised that implantation of a total knee prosthesis may change the size and shape of the joint gap. To test this hypothesis, a tensor device was used which was specifically designed to reproduce the conditions before and after implantation, including attachment of the polyethylene insert trial. This study aimed to compare the joint gaps before and after implantation of a total knee prosthesis using this new tensor device. METHODS: A total of 259 primary varus knees were included in this study. Knees were exposed using a medial parapatellar approach, and the anterior and posterior cruciate ligaments were resected. After the trial reduction, the intraoperative joint gap kinematics was measured using the tensor device. RESULTS: Implantation of a total knee prosthesis decreased the size of the extension joint gap and made it valgus, but did not influence the size or shape of the flexion joint gap. CONCLUSIONS: The present findings suggest that the classical gap technique, which creates equal and rectangular extension and flexion joint gaps in the bone cutting surface, results in an imbalance between the extension and flexion joint gaps after implantation. To achieve equal and rectangular extension and flexion joint gaps after implantation, the prepared extension joint gap should be about 2 mm larger than the flexion joint gap and slightly varus before implantation in primary varus knees. LEVEL OF EVIDENCE: Therapeutic study, Level II.

Midterm results following medial closed wedge distal femoral osteotomy stabilized with a locking internal fixation device.

PURPOSE: Aim of this study was to evaluate the subjective and radiological outcome and to evaluate the complications of a medial closing wedge osteotomy at the femur for lateral osteoarthritis with genu valgum. METHODS: Twenty-three patients with grade III to IV cartilage damage and valgus knee alignment were treated with medial closing wedge osteotomy at the distal femur. The osteotomy was stabilized with an internal plate fixator. Age varied between 25 and 55 years (mean 47 years). One patient was lost to final follow-up. RESULTS: After 3.5 years, all Knee Osteoarthritis Outcome Score (KOOS) subitems increased significantly. There was no significant difference in the subgroup analysis of KOOS subitems for patients with and without microfracture or age (>50 vs. <50 years). There were no perioperative complications. One patient had an overcorrection. All, but one osteotomy, showed stable bone healing. There was a loss of correction due to delayed bone healing in one case. Possible explanations for this complication were injury of the lateral cortex or smoking. This case required revision with bone graft and an additional lateral plate. In no case, a conversion to an endoprosthesis was necessary. CONCLUSION: The femoral medial closing wedge osteotomy is a surgical method for improving symptoms of lateral osteoarthritis in the valgus knee. LEVEL OF EVIDENCE: IV.

Mucopolysaccharide disorders in orthopaedic surgery.

The mucopolysaccharidoses (MPSs) are a family of disorders characterized by the accumulation of glycosaminoglycans, which is caused by enzyme deficiencies in the lysosomal metabolism of these normal cellular byproducts. Skeletal abnormalities are early and prominent features of MPS, and the orthopaedic surgeon is often the first healthcare provider to raise suspicion for this diagnosis. Recently developed medical therapies for the management of MPS (ie, hematopoietic stem cell transplantation, intravenous enzyme replacement therapy) have led to increased lifespan but have not had much effect on the development of skeletal deformities. Patients must be monitored carefully and treated surgically as necessary. Conditions that may require surgical management include cervical spine and atlantoaxial instability, gibbus deformity, hip dysplasia and osteonecrosis, genu valgum, and carpal tunnel syndrome. The orthopaedic surgeon should have a basic understanding of MPS and of the clinical presentation, musculoskeletal abnormalities, and radiographic findings associated with this group of disorders.