Correction of Genu Valgum in Patients With Congenital Fibular Deficiency.

BACKGROUND: Patients with congenital fibular deficiency often develop genu valgum secondary to lateral femoral condylar hypoplasia. Guided growth strategies are often performed to correct limb alignment when adequate skeletal growth remains. METHODS: A retrospective review of patients with postaxial hypoplasia of the lower extremity managed with an amputation strategy and who had a guided growth procedure for coronal plane limb malalignment during their course of treatment was performed. Clinical and radiographic data, including measures of coronal plane deformity and alignment, type of amputation, subsequent operative procedures, and complications were recorded. RESULTS: Seventeen patients (20 extremities) met study inclusion criteria (mean follow-up 8.8 y). Foot ablation and hemiepiphysiodesis for valgus deformity of the knee was performed in all extremities. The average age at the time of initial hemiepiphysiodesis was 11.2 years at an average of 8.8 years from the initial amputation procedure. The mean preoperative mechanical axis deviation was 26.5 mm, which was corrected to a mean mechanical axis deviation of 7.0 mm. Fifteen (75%) of the extremities had correction of the deformity to neutral alignment after the initial procedure. Lack of correction occurred in 3 extremities, and overcorrection occurred in 2 extremities. Additional procedures were required in 5 extremities for rebound valgus deformity after hardware removal. CONCLUSIONS: In patients with postaxial hypoplasia, regular monitoring of the residual limb for growth-related changes must occur to ensure optimal function and prosthetic fit. Timing of the guided growth procedure is critical, as younger patients may be more likely to experience rebound deformity. Families and patients should be made aware that growth might be unpredictable in this population with risks of both overcorrection and undercorrection. LEVEL OF EVIDENCE: Level IV-case series.

Off-label: The results of adjunctive bone morphogenetic protein for challenging femur fractures; a review of two cases.

Background: Although bone morphogenetic proteins (BMPs) are used as an adjunct to promote healing, they may have unintended effects such as heterotopic ossification (HO). The literature is limited regarding the effect of using off-label BMPs for femur fractures. Case presentation: We report two outcomes after off-label use of BMPs for the treatment of femur fractures and propose a possible explanation for the difference. Conclusions: BMPs are critical osteoinductive factors in injured bone and muscle that facilitate bony healing. However, it may be important to recognize the potentially negative effects of adding BMP to bone graft material in certain cases to stimulate bone repair. We hope this case series helps surgeons consider the risks and benefits of using BMP for femur fractures, and therefore to decide with caution when BMP is indicated.

High Complication Rate After Percutaneous Screw Fixation for Valgus-Impacted Femoral Neck Fractures Without Sagittal Malalignment.

OBJECTIVES: To evaluate the rate of reoperation in patients without sagittal plane malalignment who underwent percutaneous screw fixation of a valgus-impacted femoral neck fracture. DESIGN: Retrospective case series. SETTING: Two Level 1 academic trauma centers. PATIENTS AND INTERVENTION: Two hundred seven patients >50 years of age with valgus-impacted femoral neck fractures treated with at least 3 large-diameter (>6.5 mm) cancellous screws from 2013 to 2019. Patients were excluded if there was a sagittal plane fracture deformity. MAIN OUTCOME MEASUREMENTS: The primary outcome was reoperation. Secondary outcomes considered "major complications" included: avascular necrosis, varus collapse or implant cutout, nonunion, deep infection, and hematoma requiring reoperation. Surgical fixation strategies (screw configuration, aim) and implant type (partial vs. fully threaded cancellous screws) were secondarily compared. RESULTS: Average patient age was 77 years, and median clinical follow-up was 658 days. Thirty-one patients (15%) required reoperation, and the major complication rate was 17.3% (36 complications in 33 patients). Logistic regression analysis demonstrated a higher risk of reoperation with constructs consisting of all partially threaded screws (17.0%) compared with the use of at least 1 fully threaded screw (7.5%) when an inverted triangle configuration was used (odds ratio, 2.50; 95% CI, 0.81-7.77). CONCLUSIONS: This study demonstrated a relatively high rate of reoperation and major complications in patients with valgus-impacted femoral neck fractures without sagittal malalignment treated with in situ percutaneous screw fixation. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.