Limb Discrepancy Research Articles

The application and effect of bispherical augment in acetabular defects reconstruction

Objective: To evaluate the clinical effect of bispherical augment in acetabular defects reconstruction in hip revision. Methods: This is a retrospective case series study. A retrospective analysis of 119 patients (124 hips) patients who underwent hip revision surgery and reconstructed with bispherical augment for acetabular bone defects from January 2019 to December 2023 was performed. There were 57 males (58 hips) and 62 females (66 hips), aged (65.0±11.8) years (range:40 to 102 years). The body mass index was (23.9±3.5) kg/m2 (range:16.1 to 32.2 kg/m2). Acetabular bone defects were typed as follows: 2 hips in Paprosky type ⅡA, 29 hips in type ⅡB, 34 hips in type ⅡC, 31 hips in type ⅢA, and 28 hips in type ⅢB, of which 9 patients (9 hips) were combined with pelvic discontinuity. Differences in Harris hip score (HHS) and lower limb discrepancy (LLD) were compared between preoperatively and final follow-up. The height of the hip center of rotation and the horizontal distance from the center of rotation to the teardrop were measured by radiographs before and after surgery, and prothesis stability and the occurrence of postoperative complications were evaluated. Data were compared using the paired sample t test. Results: All patients successfully completed the operation. The operation time was (167.0±53.4) minutes (range:90 to 380 minutes) and the intraoperative bleeding was (345.3±124.2) ml (range:100 to 1 200 ml). The height of the hip center of rotation decreased from (39.7±13.0) mm preoperatively to (21.8±7.1) mm postoperatively and the horizontal distance from the center of rotation to the teardrop increased from (34.0±10.1) mm preoperatively to (38.5±5.9) mm postoperatively, and the differences were statistically significant (t=15.859, P<0.01; t=5.266,P<0.01). All the patients were followed up for (26.1±15.4) months (range:6 to 60 months). At the last follow-up, HHS improved from (35.2±10.0) points preoperatively to (85.5±9.5) points, and the difference was statistically significant (t=50.723,P<0.01). LLD decreased from (2.1±1.1) cm preoperatively to (0.5±0.5) cm, and the difference was statistically significant (t=13.767, P<0.01). All acetabular components were stable and free of displacement on imaging during follow-up. Three patients suffered dislocation and received closed reduction, all prosthesis were in good position during follow-up. No dislocation, loosening, fracture, recurrence of infection and vascular nerve injury occurred in other patients. Conclusion: Bispherical augment can effectively reconstruct acetabular bone defects, restore the hip center of rotation, and improve hip joint function scores at short and mid-term follow-up.

Change in lower limb length following total knee arthroplasty

BackgroundLength variations of the lower limbs after total knee arthroplasty (TKA) constitute a poorly evaluated parameter and can be associated with worse functional outcomes. The objectives of this study were to: 1) describe the variations in the lower limb length after TKA according to the digital accuracy of the computerized navigation system used for prosthesis implantation, 2) describe patient sensation of limb length modification at 3 months postoperatively and to identify its risk factors, 3) identify factors affecting lower limb length modification and to analyze the predictive value causing in the patient the sensation of lower limb discrepancy. HypothesisWe hypothesize that there may be a lower limb length discrepancy after TKA, which may cause some distress to the patient. Patients and methodsThis prospective study included 100 TKAs implanted with navigation gap-balanced adjusted mechanical alignment. Were compared the length of the lower limb before and after implantation and the patient’s changes in leg length perception at 3 months postoperatively. A subgroup analysis was performed according to preoperative knee deformities: varus knee was an HKA < 177 °, normal knee was an HKA between 117°-183 ° and valgus was an HKA >183 °. ResultsNinety-seven out of 100 patients experienced lengthening compared to the preoperative ipsilateral length, and twenty-three experienced lengthening greater than 10 mm. The mean lengthening was 7.3 mm (maximum 24.8 mm). Lengthening was significantly greater in valgus knees 9.9 mm [range, 2.0-24.8] than in varus 7.2 mm [range, 1.46-19.4] and normal knees 4.11 mm [range, 0.4-11.4] (p < 0.05). The correction of frontal and sagittal deformation were risk factors for limb length modification (OR = 0.595; 95% CI (0.544-0.816) (p = 0.001), OR = 0.396; 95% CI (0.351-0.653) (p = 0.001)).Twenty-two patients reported a sensation of limb length change: 11 (50%) reported equalization, whereas the remainder reported lengthening with a leg length difference. The preoperative sensation of lower limb length inequality was the unique factor affecting the patient’s perception post-surgery (OR = 37.50; 95% CI (9.730-144.526) (p = 0.0001)). A threshold value of 6.6 mm was identified for the sensation of limb length modification. ConclusionNavigation is a tool for describing ipsilateral leg length variations after TKA. These variations are significant and perhaps explain some patient dissatisfaction. A partial correction of the frontal deformity according to the knee phenotype could limit the risk of modification of the native length. Level of evidenceIV; Descriptive therapeutic prospective study.

The Role of Sole Lift in Treating Pediatric Idiopathic Scoliosis with Mild Thoracolumbar/Lumbar Curve.

Lower limb discrepancy (LLD) was frequently observed in patients with idiopathic scoliosis (IS), potentially associated with etiopathogenesis. Although sole lifts had been proposed as a conservative treatment for IS, evidence supporting their efficacy was limited. This study aimed to assess the effects of sole lift intervention on pediatric patients with mild IS, specifically focusing on thoracolumbar/lumbar (TL/L) curvature. Twenty patients, with an average age of 12.3 ± 3.1 years and presenting mild TL/L curve (15.6° ± 6.2°), were selected from a pool of 267 pediatric IS patients in the outpatient of our spine center from February 2023 to August 2023. Inclusion criteria comprised a main TL/L curve ranging between 10° and 40°, the lower limb positioned at the convexity of the main curve, and LLD of less than 2 cm; individuals requiring bracing or surgical intervention were excluded. Custom sole lifts were used to address the shorter lower limb with the objective of leveling the pelvis. Radiographic evaluations were conducted both before and after intervention using standing full spine posteroanterior radiographs and full leg length radiographs. Statistical analysis was undertaken to evaluate curve correction and its associations with other influencing factors. The mean structural and functional LLD were 7.1 ± 4.5 mm and 7.1 ± 4.1 mm, respectively. Among the 20 patients, four exhibited structural LLD greater than 10 mm. The average follow-up duration was 6.4 ± 1.9 months (range: 3-8 months). Following sole lift intervention (7.0 ± 3.0 mm), a significant reduction was observed in the TL/L curve compared to the pre-sole lifting measurements (15.6° ± 6.2° vs. 12.1° ± 7.2°, p < 0.001), as well as a notable decrease in the thoracic curve (12.2° ± 4.0° vs. 8.6° ± 6.3°, p = 0.064). Nine patients experienced a significant curve reduction of ≥5°, while eight showed a reduction between 0° and 5°; however, two patients exhibited no change in curve magnitude. Furthermore, the correction rate of the TL/L curve correlated significantly with functional LLD (r = -0.484, p = 0.030) and pelvic obliquity (r = -0.556, p = 0.011), highlighting the active pelvic compensation in maintaining balance between the spine and lower limbs. Conversely, no significant correlation was observed between curve correction and structural LLD (p > 0.05). Additionally, even after adjusting for other influencing factors, the TL/L Cobb angle remained significantly different between pre- and post-sole lifting (p = 0.037). This study confirmed the effectiveness of sole lift intervention in correcting TL/L and thoracic curves among the mild IS children with a main TL/L curve, providing a supplementary conservative treatment option for patients with the lower limb at the convexity of the main curve. Moreover, our findings underscored the active compensation of the lower limbs and the pelvis in the etiopathogenesis of IS, highlighting the importance of considering their influence in treatment strategies.

Performance of Microsoft Azure Kinect DK as a tool for estimating human body segment lengths

The Microsoft Kinect depth sensor, with its built-in software that automatically captures joint coordinates without markers, could be a potential tool for ergonomic studies. This study investigates the performance of Kinect in limb segment lengths using dual-energy X-ray absorptiometry (DXA) as a reference. Healthy children and adults (n = 76) were recruited for limb length measurements by Kinect and DXA. The results showed consistent ratios of arm, forearm, thigh, and leg lengths to height, which were 0.16, 0.14, 0.23, and 0.22 respectively, for both age groups and methods. Kinect exhibited perfect correlation among all limb lengths, indicating fixed proportions assumed by its algorithm. Comparing the two methods, there was a strong correlation (R = 0.850–0.985) and good to excellent agreement (ICC = 0.829–0.977), except for the right leg in adults, where agreement was slightly lower but still moderate (ICC = 0.712). The measurement bias between the methods ranged from − 1.455 to 0.536 cm. In conclusion, Kinect yields outcomes similar to DXA, indicating its potential utility as a tool for ergonomic studies. However, the built-in algorithm of Kinect assumes fixed limb proportions for individuals, which may not be ideal for studies focusing on investigating limb discrepancies or anatomical differences.

Unrecognized sciatic lipomatosis of the nerve diagnosed by telehealth: illustrative case.

Lipomatosis of the nerve (LN) is a rare congenital hamartoma in which abundant fibroadipose tissue is found within the epineurium of peripheral nerves. It is frequently associated with nerve territory overgrowth affecting bones or soft tissues. The clinicoradiological features are well known and pathognomonic. A 38-year-old female was evaluated via telehealth for worsened sciatica after the resection of a sciatic notch lipoma, after having been evaluated over a decade for symptoms. Virtual physical examination revealed previously unrecognized subtle limb discrepancy (i.e., overgrowth). Although preoperative radiographs were unavailable during the initial evaluation, postoperative magnetic resonance imaging studies showed evidence of sciatic nerve LN. A diagnosis of LN and nerve territory overgrowth was established. Despite its limitations, telehealth can be an effective alternative or adjunct to in-person evaluations in making complex diagnoses. Dedicated examination without clinical suspicion can miss subtle findings. An iterative process prompted by a focused history, knowledge of clinical associations, and pattern recognition can facilitate an accurate diagnosis without obvious face-to-face visual clues. In patients with rare disorders, asynchronous evaluation allows in-person visits to be supplemented by subsequent telehealth virtual physical exam findings. This case illustrates how examination via telehealth can be used to effectively diagnose a rare syndrome.

Ilizarov method and its combined methods in the treatment of long bone defects of the lower extremity: systematic review and meta-analysis

BackgroundIlizarov method has become one of primary methods for treating bone defects. Currently, there is growing trend in the application of modified Ilizarov methods (e.g., applying unilateral external fixators or with flap tissue) and its combined methods (e.g., Ilizarov method with antibiotic spacer or internal fixation) to manage bone defects. However, there is a lack of studies with systematical evaluation of the clinical effects of these evolving methods. This study aimed to conduct a systematic review and meta-analysis for overall evaluating the clinical effects on long bone defects of lower extremity in Ilizarov methods and its combined methods.MethodsStudies were identified in three electronic databases (Pubmed, Embase and Cochrane Library) from the earliest indexing year through November 01, 2022, and relevant data were extracted subsequently. The total number of participants, number of participants with bone unions, bone result or functional result, and related complications including pin infection, pin loosening, pain, refracture, limb discrepancy, malalignment, joint stiffness, recurrent infection, and amputation were extracted in this study. Then, union rate (defined as the proportion of patients who achieved bone unions) and specific complication incidence rate (defined as the proportion of patients who experienced specific complication) were pooled estimated respectively. Relative risk (RR) was used for comparing the clinical effects among various Ilizarov technique.ResultsSixty-eight case series studies, 29 comparative studies, and 3 randomized clinical trials were finally included. The union rate of Ilizarov methods was 99.29% (95% CI: 98.67% ~ 99.86%) in tibial defects and 98.81% (95% CI: 98.81% ~ 100.00%) in femoral defects. The union rate of Ilizarov method with antibiotic spacer and intramedullary nail in tibial defects was 99.58% (95% CI: 98.05% ~ 100.00%) and 95.02% (95% CI: 87.28% ~ 100.00%), respectively. Compared to the Ilizarov methods, the union rate of the Ilizarov method with antibiotic spacer in tibial defects increased slightly (RR = 1.02, 95% CI: 1.01 ~ 1.04). Meanwhile, compared to Ilizarov methods, we found lower excellent rate in bone result in Ilizarov method with antibiotic spacer, with the moderate to high heterogeneity. Compared to the Ilizarov method, lower rate of pin infection, higher rate of recurrent infection and amputation were observed in Ilizarov method with intramedullary nail, however, the findings about the comparison of pin infection and recurrent infection between the two groups were presented with high degree of statistical heterogeneity.ConclusionOur study confirmed the reliable treatment of Ilizarov methods and its combined technique on long bone defects, and founded there were significant differences on some complications rate between Ilizarov methods and its combined technique. However, the findings need to be confirmed by further studies.

Limb salvage and functional recovery in infected nonunion of the distal tibia treated with the Ilizarov techniques

IntroductionTreatment of infected nonunion of the distal juxta-articular tibia is a challenge due to a short distal fragment, deformity, thin soft-tissue envelope, and active infection. There is still no consensus on the approach that is able to maximally salvage the limb and ankle function. Material and methodsInfected juxta-articular nonunion of the distal tibia was managed with two Ilizarov techniques, monofocal compression (MC) used in 12 patients and bifocal compression-distraction (BCD) in 6 patients. The choice of the technique depended on the size of the postresection defect, ≥3 cm or ≤3 cm, respectively. The tactics of functional approach were careful debridement, insertion of wires in the distal fragment so that they do not penetrate the ankle joint, stable fixation, and temporary bridging of the ankle and forefoot. MSCT was used along with regular radiography to assess the union and regeneration. Ankle functions were evaluated with AOFAS ankle-hindfoot score system. ResultsBone consolidation, infection arrest and ankle function improvement were achieved in all patients. External fixation continued 221.7 ± 15.1 days for MC and 235 ± 25.8 days for BCD. Complications were wound divergence, wire-tract infection, premature consolidation of the fibula, and hypoplastic regeneration in one case. The mean functional AOFAS score after treatment was 90.7 ± 2.5 points in MC and 89.7 ± 1.3 in BCD patients. Residual limb discrepancy after MC ranged 0–4 cm. Bone shortening was compensated in BCD patients. ConclusionLimb-salvage and functional approach to the treatment of infected nonunion of the juxta-articular distal tibia with the Ilizarov techniques achieves good outcomes. It provides bone infection arrest, consolidation, defect compensation and significantly improves the ankle joint function.

DOUBLE LEVEL KNEE OSTEOTOMY IN BIFOCAL (FEMUR AND TIBIA) VALGUS MALALIGNED KNEES: WHAT ARE THE OUTCOMES AND LIMB LENGTH DISCREPANCY?

AbstractIntroductionDouble-level knee osteotomy (DLO) is a challenging procedure that requires precision in preoperative planning and intraoperative execution to achieve the desired correction. It is indicated in cases of severe varus or valgus deformities where a single-level osteotomy would yield significantly tilted joint line obliquity (JLO).MethodsA single-centre, retrospective analysis of prospectively collected data for 26 patients, who underwent DLO by PSCGs for valgus malaligned knees. Post-operative alignment was evaluated and the delta for different lower limb alignment parameters were calculated; HKA, MPTA, and LDFA. At the two-year follow-up, changes in KOOS sub-scores, UCLA scores, lower limb discrepancy, and mean time to return to work and sport were recorded. All intraoperative and postoperative complications were recorded.ResultsThe postoperative mean ΔHKA was 0.9 ± 0.9°, the mean ΔMPTA was 0.7 ± 0.7°, and the mean ΔLDFA was 0.7 ± 0.8° (all values with p &gt; 0.05). All KOOS subscores’ mean values were improved to an extent two-fold superior to the reported MCID (all with p &lt; 0.0001). There was a significant increase in the UCLA score at the final follow-up (5.4 ± 1.5 preoperatively versus 7.7 ± 1.4, p &lt; 0.01). The mean time to return to sport and work was 4.7 ± 1.1 and 4.3 ± 2.1 months, respectively. There was an improvement in Lower-limb discrepancy preoperative (LLD = 1.3+/−2cm) to postoperative measures (LLD= 0.3 +/− 0.4 cm) p=0.02.ConclusionDLO is effective and safe in achieving accurate correction in bifocal valgus malaligned knees with maintained lower limb length and low complication rate with no compromise of JLO.

Correction of tibial multiplanar deformities using single Taylor external fixator combined with biplanar osteotomy

To investigate the effectiveness of single Taylor external fixator combined with biplanar osteotomy on correction of tibial multiplanar deformities. Between October 2016 and December 2021, 11 patients with tibial multiplanar deformities (20 sides) were treated with single Taylor external fixator and biplanar osteotomy. Of them, 4 were male and 7 were female; the average age ranged from 13 to 33 years (mean, 21.9 years). Diagnosis included rickets severe genu varum deformity (7 cases, 14 sides), rickets severe genu valgum deformity (2 cases, 4 sides), multiple osteochondromatosis calf deformity (1 case, 1 side), neurofibromatosis medial lower leg anterior arch deformity with short of leg (1 case, 1 side). After fibular osteotomy and tibial multiplanar osteotomy, a Taylor external fixator was installed. After operation, the deformities were corrected successively and fixed completely. The osteotomy healed, then the external fixator was removed. Before operation and at 12 months after operation, the full-length X-ray films were taken. The leg-length discrepancy, medial proximal tibial angle (MPTA), lateral distal tibial angle (LDTA), posterior proximal tibial angle (PPTA), anterior distal tibial angle (ADTA), and tibial rotation angle were measured. The degree of lower limb deformity was scored with reference to a customized tibial mechanical axis scoring table. Osteotomy was successfully completed without neurovascular injury and other complications. The external fixator was adjusted for 28-46 days, with an average of 37 days, and the external fixator was worn for 136-292 days, with an average of 169 days. Mild needle infection during the fixation period occurred in 3 sides, refracture at the distal tibial osteotomy in 1 side after removing the external fixator, and nonunion of the distal fibular osteotomy in 1 side. All patients were followed up 369-397 days (mean, 375 days). At 12 months after operation, the lower limb discrepancy decreased, but there was no significant difference ( P>0.05). MPTA, LDTA, PPTA, ADTA, and tibial rotation angle improved, and the differences in LDTA, ADTA, and tibial rotation angle were significant ( P<0.05). The score of lower limb deformity was significantly higher than that before operation ( P<0.05), and the results were excellent in 9 sides, good in 8 sides, fair in 3 sides, with the excellent and good rate of 85%. Single Taylor external fixator combined with biplanar osteotomy is effective in the correction of tibial multiplanar deformities.

Cutis marmorata telangiectatica congenita: Incidence of extracutaneous manifestations and a proposed clinical definition.

Cutis marmorata telangiectatica congenita (CMTC) is a capillary malformation characterized by congenital, reticulated, well-demarcated dark blue, red-purple, or violaceous macules or plaques, with a coarse fixed livedo pattern. Nearly always, contiguous areas of skin atrophy and/or ulceration are present. CMTC is usually localized but may rarely be generalized. Such generalized cases may be a feature of Adams-Oliver syndrome (AOS). The nosologic confusion surrounding the term CMTC and uncertainty about the risk of associated abnormalities hinders the appropriate workup of patients and prognostic counseling for families. We hypothesized that the risk of associated anomalies in children with localized CMTC is very low. We performed a literature review and retrospective review of patients with CMTC to propose a more precise clinical definition and ascertain the risk of associated anomalies. We included 78 patients determined to have a diagnosis of CMTC based on consensus. The majority of patients had localized CMTC. Most patients with generalized CMTC met the criteria for the diagnosis of AOS. The associations found in patients with localized CMTC were mostly dermatological, with atrophy, ulcerations, or erosions present in 71%. Extracutaneous findings were present in 34.4% of patients and consisted mainly of extremity asymmetry (24.5%) that improved over time. Our study showed a very low frequency of extracutaneous anomalies among patients with localized CTMC, ipsilateral limb discrepancy being the most common. We did not find a strong association with any other visceral anomalies that would justify routine evaluation in patients with localized CMTC.

The Effect of Distraction Osteogenesis on Peripheral Nerve Regeneration in Rats: A Preliminary Study In Vivo

Distraction osteogenesis (DO) is a widely employed method for the treatment of limb discrepancies and deformity correction. This study aimed at observing the histomorphological and ultrastructural changes of peripheral nerves around the distraction area during DO and investigating the self-repair mechanism of peripheral nerves in a rat DO model. Sixty rats underwent right femoral DO surgery and were randomly separated into six groups: Control (latency, no distraction, n = 10), Group 0-week (after distraction, n = 10), Group 2-week (n = 10), Group 4-week (n = 10), Group 6-week (n = 10), and Group 8-week (n = 10) at consolidation phase. The right femur of rats in Group 0-week, Group 2-week, Group 4-week, Group 6-week, and Group 8-week was subjected to continuous osteogenesis distraction at a rate of 0.5 mm/day for 10 days. Motor nerve conduction velocity (MNCV) of the sciatic nerve, sciatic function index (SFI), histological analyses, and transmission electron microscopy were conducted to evaluate nerve function. The MNCV and SFI of Group 0-week, Group 2-week, Group 4-week, and Group 6-week were significantly lower than the Control ( P &lt; 0.05 ). No statistical differences were found between the Control and Group 8-week in terms of MNCV and SFI ( P &gt; 0.05 ). Injuries to nerve fibres and nodes of Ranvier were observed in the Group 0-week, whereas the nerve fibres returned to the normal arrangement in the Group 8-week and oedema of myelin disappeared, with the continuity of axons and lamellar structure of myelin being restored. Femoral DO in rats with a rate of 0.5 mm/day may cause sciatic neurapraxia, which can be self-repaired after 8 weeks of consolidation. The paraneurium around the sciatic nerve enables it to glide during the distraction phase to reduce the occurrence of injurious changes.

Bone Transport in the Management of Post-Osteomyelitis Tibial Defects in Pediatric Population. A Long Term Follow-up Study in Uganda

Background: This study was designed to evaluate the long-term results and complications of using the bone transport technique in the management of post-osteomyelitis tibial defects in a low income country. Design: Retrospective study in a cohort of pediatric patients. Methods: Twenty-two patients were included in the study; all patients were treated between 2005 and 2014. The mean age at time of surgery was 9.5 years. The mean bone defect was 8.2 cm. Transport was done using both ring and monolateral external fixators; the fixator stayed in place for 290 days on average. Clinical and radiological evaluations were performed after a minimum follow-up period of 7 years. Patients were interviewed by social workers with focus on the psychosocial and economic costs of the procedure. Results: The bone and soft tissues management required a total of ninety-one surgeries, with an average of four surgeries per child. Eradication of infection was obtained in all patients. Bone results were graded as excellent in 10, good in 7, fair in 2 and poor in 3. Functional results were graded as excellent in 8, good in 6, fair in 7 and poor in 1. Major and minor complications were numerous during the bone transport procedure. Three cases of non-union at the docking point were observed. Twelve patients had a limb length discrepancy, four had slight angular deformities. Reduced range of motion was observed both in the ankle (n=4) and knee (n=2). Seven joint fusions were noted, two knees and five ankles. Conclusion: Bone transport is a valid option in the management of bone defects in children, providing satisfactory long-term outcomes. Bone gaps, soft tissue defects, limb discrepancy and joint disorders can be managed concurrently. The procedure is lengthy and prone to complications.

Combination of external fixation using digital six-axis fixator and internal fixation to treat severe complex knee deformity

BackgroundSevere knee valgus/varus or complex multiplanar deformities are common in clinic. If not corrected in time, cartilage wear will be aggravated and initiate the osteoarthritis due to lower limb malalignment. Internal fixation is unable to correct severe complex deformities, especially when combined with lower limb discrepancy (LLD). Based on the self-designed digital six-axis external fixator Q spatial fixator (QSF), which can correct complex multiplanar deformities without changing structures, accuracy of correction can be improved significantly.MethodsThis retrospective study included 24 patients who suffered from complex knee deformity with LLD treated by QSF and internal fixation at our institution from January 2018 to February 2021. All patients had a closing wedge distal femoral osteotomy with internal fixation for immediate correction and high tibia osteotomy with QSF fixation for postoperative progressive correction. Data of correction prescriptions were computed by software from postoperative CT scans.ResultsMean discrepancy length of operative side was 2.39 ± 1.04 cm (range 0.9–4.4 cm) preoperatively. The mean difference of lower limb was 0.32 ± 0.13 cm (range 0.11–0.58 cm) postoperatively. The length of limb correction had significant difference (p < 0.05). The mean MAD and HKA decreased significantly (p < 0.05), and the mean MPTA and LDFA increased significantly (p < 0.05). There were significant increase (p < 0.05) in the AKSS-O, AKSS-F and Tegner Activity Score. The lower limb alignment was corrected (p < 0.05). The mean time of removing external fixator was 112.8 ± 17.9 days (range 83–147 days).ConclusionsComplex knee deformity with LLD can be treated by six-axis external fixator with internal fixation without total knee arthroplasty. Lower limb malalignment and discrepancy can be corrected precisely and effectively by this approach.

Double-level knee osteotomy accurately corrects lower limb deformity and provides satisfactory functional outcomes in bifocal (femur and tibia) valgus malaligned knees.

Double-level knee osteotomy (DLO) is a challenging procedure that requires precision in preoperative planning and intraoperative execution to achieve the desired correction. It is indicated in cases of severe varus or valgus deformities where a single-level osteotomy would yield significantly tilted joint line obliquity (JLO). This study aimed to evaluate the effectiveness of DLO in achieving accurate correction without compromising JLO, using patient-specific cutting guides (PSCGs), in cases of bifocal valgus maligned knees. A single-centre, retrospective analysis of prospectively collected data for a total of 26 patients, who underwent DLO by PSCGs for valgus malaligned knees, between 2015 and 2020. Post-operative alignment was evaluated and the delta for different lower limb0.05, not statistically significant (ns)). All KOOS subs alignment parameters was calculated; the hip-knee-ankle angle (ΔHKA), medial proximal tibial angle (ΔMPTA), and lateral distal femoral angle (ΔLDFA). At the two-year follow-up, changes in the KOOS sub-scores, UCLA scores, lower limb discrepancy (LLD), and mean time to return to work and sport were recorded. All intraoperative and postoperative complications were recorded. The Mann-Whitney U test with a 95% confidence interval (95% CI) was used to evaluate the differences between two variables; one-way ANOVA between more than two variables and the paired Student's t-test was used to estimate the evolution of functional outcomes. The postoperative mean ΔHKA was 0.9 ± 0.9°, the mean ΔMPTA was 0.7 ± 0.7°, and the mean ΔLDFA was 0.7 ± 0.8° (all values with p > 0.05, not statistically significant (ns)). All KOOS subscore's mean values were improved to an extent two-fold superior to the reported minimal clinically important difference (MCID) (all with p < 0.0001). There was a significant increase in the UCLA score at the final follow-up (5.4 ± 1.5 preoperatively versus 7.7 ± 1.4, p < 0.01). The mean time to return to sport and work was 4.7 ± 1.1 and 4.3 ± 2.1months, respectively. There was an improvement in Lower-limb discrepancy preoperative (LLD = 1.3 ± 2cm) to postoperative measures (LLD = 0.3 ± 0.4cm), ns. Complications were 2 femoral hinge fractures, 2 deep vein thromboses, 1 delayed tibial healing, and 1 hardware removal for hamstring irritation syndrome. DLO is effective and safe in achieving accurate correction in bifocal valgus malaligned knees with maintained lower limb length and low complication rate with no compromise of JLO. III.

Treatment of Infected Tibial Metaphyseal Nonunions Using the Ilizarov Method: Protocol for a Prospective Nonrandomized Study

The management of infected metaphyseal nonunion of the tibia is devastating, especially when associated with significant bone loss, poor soft tissues, draining sinuses, axial deformity, knee or ankle joint stiffness, limb discrepancy, and multiresisted pathogens. A systematic review, performed recently by the primary investigators but not yet published, yielded the lack of studies in the field and the huge heterogeneity of the presented results. We found several bias and controversies such as no clear definition of the exact part of the tibia where the nonunion was located, the pathogen causing the fracture-related infection, the number of previous interventions and time to presentation, and the exact type of treatment methods including the use of muscle flaps or bone grafting. Time to final union as a functional score is another important but missing data. The proposed study is designed to evaluate a sufficient number of patients with infected metaphyseal tibial nonunions using various general health, functional, and bone scores. This prospective clinical trial study, with a minimum follow-up period of 36 months, focuses on the effectiveness of the Ilizarov method after radical nonunion debridement and targeted antibiotic therapy in patients with infected metaphyseal tibial nonunions. The primary outcomes would be the definite healing of nonunion and infection-free results. Secondary outcomes would be limb alignment and discrepancy, alteration in the patient's quality of life, and functional results. A power analysis calculated a minimum of 11 patients to obtain statistical power, but we aim to include at least 25 patients. Limb discrepancy, clinical validation of infection eradication and fracture healing, radiographic validation, and patient-reported outcome measures will be highlighted and correlated. Statistical analysis of the results will offer data missing from the literature so far. Measurements are scheduled at specific times for each patient: preoperatively, 3 and 6 months postoperatively, 1 month after Ilizarov frame removal, and once per semester afterward until the end of the follow-up period (minimum 36 months). Laboratory evaluation will be assessed once per month. Any complication will be reported and treated when it occurs. The trial has already started. It was funded in June 2020. As of May 2022, 19 participants have been recruited and no major complications have been noticed yet. Data analysis will be performed after data collection ends, and results will be published afterward. An infected metaphyseal tibial nonunion is a rare condition with limited treatment options and many controversies. There is no consensus in the literature about the best treatment strategy, and this lack of evidence should be fulfilled. International Standard Randomized Controlled Trial Number (ISRCTN) 30905788; https://www.isrctn.com/ISRCTN30905788. DERR1-10.2196/39319.

Anterolateral approach may be superior to posterolateral approach in controlling postoperative lower limb discrepancy in primary total hip arthroplasty: A single-center, retrospective cohort study.

This study aims to investigate the possible association and comparison between anterolateral approach (ALA) and posterolateral approach (PLA) and postoperative lower limb discrepancy (LLD) in selective total hip arthroplasty (THA). April 2021 and July 2021, a total of 266 consecutive patients (126 males, 140 females; mean age: 46.7±13.6 years; range, 22 to 60 years) who underwent unilateral primary THA via the ALA or the PLA were retrospectively analyzed. The operations were performed by a single surgical team. All patients were divided into two groups according to the approach: ALA group (n=66) and PLA group (n=200). Relevant data were recorded. Diagnosis including hip osteoarthritis, developmental dysplasia of the hip (DDH), aseptic avascular necrosis (AVN), and inflammatory arthritis were noted. Perioperative follow-up radiographs were evaluated and measured to compare the postoperative LLD and offset. The association between two approaches and postoperative LLD and offset was analyzed using the univariate and multivariate linear regression analysis. The mean follow-up was 20±3.7 (range, 16 to 25) months. Univariate analysis revealed that the postoperative LLD, the postoperative acetabular offset, and hospital costs were lower in the ALA group than the PLA group (p<0.01). However, the offset and length of stay were comparable between the two groups (p>0.05). Multivariate analysis revealed that the PLA (β=4.71; 95% confidence interval [CI]: 1.78 to 7.64), preoperative LLD (β=0.29; 95% CI: 0.21 to 0.37), DDH (β=5.01; 95% CI: 1.47 to 8.55), and AVN (β=3.81; 95% CI: 0.50 to 7.12) were the main contributors to the postoperative LLD. Our study results suggest that the ALA may be superior to the PLA in controlling the postoperative LLD among some of the selective unilateral primary THA patients. Both the ALA and the PLA were comparable in terms of the restoration of offset.

The Floating Knee in Pediatric Patients: A Single-Center Retrospective Study From a Referral Center.

IntroductionAn ipsilateral fracture of the femur and tibia (also known as floating knee) is a rare injury in pediatric patients. Recent advances rapidly made the use of intramedullary elastic nails the standard of care in the management of long bone fractures, including floating knee injuries, in patients with immature skeletons. Currently, we have observed a trend of fixing both fractured bones, thus improving functional outcomes, and reducing sequelae. The aim of this study was to report our experience in the management and functional outcomes of floating knee injuries in a single trauma-I level center.Materials and methodsThis is a retrospective study of consecutive cases from June 1, 2018, to March 31, 2022, from a single trauma center. Preoperative and postoperative records and radiographs were assessed, including the epidemiological data and characteristics of the fractures type of treatment, mechanism of injury, complications, and functional evaluation at the last follow-up, which was performed according to the criteria described by Karlstrom and Olerud.ResultsTwenty-five patients were included during the four years of study, of which 18 were male (72%), and the mean age was 9.6 years. Overall, 96% of the cases were related to traffic accidents. An analysis of the provided treatment showed that 19 cases (76%) were resolved with surgery on at least of the bones, and six cases were managed with simultaneous orthopedic treatments in both injuries. Excellent outcomes were achieved in 15 cases (60%), good outcomes in three, fair outcomes in five, and poor outcomes in one. Concerning the classification of injuries according to the criteria developed by Letts and Vincent,it was observed that type D was the most frequent one. With regard to exposed bone injuries, 15 cases presented with open fractures. Complications were found in eight (32%) cases, of which five were related to limb discrepancy and three with functional limitations of the knee, with changes in its range of motion. There was also one case of nonunion of the distal tibia.ConclusionTraffic accidents are the main cause of floating knees. Surgical management of the fractures brought satisfactory outcomes and reduced complications. Thus, fixation of injuries is recommended for early return to daily activities and for a reduction in residual complications.

Lower limb discrepancy after total knee arthroplasty. Is it really an issue?

Lower limb discrepancy after total knee arthroplasty (TKA) is common. The main objective of this study is to evaluate the incidence of lower limb discrepancy after TKA. this is an observational analytical retrospective cohort study. We have included all the patients who underwent unilateral TKA with the same type of implant. The limb length was measured with a panoramic lower limb x-ray. The cut-off point to consider the discrepancy was > 10 mm. The type of deformity and the functional outcomes were evaluated. In a total of 60 patients, 18 (30%) showed a lower limb discrepancy. Out of the patients who presented discrepancy, the most frequent deformity was valgus deformity with a 55,6% followed by varus deformity with 38.89% and 5.56% with neutral axis. The functional outcomes according to the KSS score and the postoperative knee KSS score demonstrated no difference in long term follow up between both groups. the incidence of lower limb discrepancy after TKA was 30%. None of the patients required surgery as a consequence of the discrepancy. The functional outcomes and pain in a long term follow up did not demonstrate differences between both groups.

A novel limb-salvage reconstruction strategy with a custom hemipelvic endoprosthesis and preserved femoral head following the resection of periacetabular tumors: A preliminary study.

The treatment of periacetabular malignancy frequently challenges surgeons. To simplify the surgical procedure, we performed a novel reconstruction strategy preserving the femoral head for patients with periacetabular malignancies. We retrospectively reviewed 14 patients who underwent total en bloc resection of a periacetabular tumor and reconstruction of the hip joint with an individualized hemipelvic endoprosthesis and remaining femoral head from July 2015 to January 2019 at our center. Regions of pelvic resection: region II-4 (28.6%), region I + II-5 (35.7%), region II + III-2 (14.3%) and region I + II + III-3 (21.4%). The oncological outcomes were that 13 patients survived without disease and one patient survived with lung metastasis. None of the patients experienced local recurrence (range: 20-62 months; mean: 32 months). The incidence of postoperative complications was 35.7%, including delayed wound healing and deep venous thrombosis. No prosthesis-related complications occurred until the last follow-up in this study (range: 20-62 months; mean: 32 months). The mean Musculoskeletal Tumor Society functional outcome score was 23.2. The mean Toronto Extremity Salvage Score of the patients was 75.7 points, with a mean limb discrepancy of 1.51 cm (range: 0.5-3.2 cm). Reconstruction with preservation of the femoral head showed acceptable early functional and oncological outcomes, and it had an acceptable complication rate.

Abstract 48: A typical neurofibromatosis type 1 presenting as overgrowth syndrome

A 6 years old boy presented to the endocrinology department as unilateral left leg overgrowth since birth. Limb discrepancy had been negligible at birth but became evident as the child gained height and further he developed a limping gait by 2 years of age. On examination, he had multiple café au lait spots of > 5 mm over the body and hyperpigmentation on anterolateral aspect of left leg which turned out to be a venous malformation on color Doppler and MRI of the leg. There was no other neuro cutaneous marker and no family history of similar illness or any other neuro cutaneous lesions or any abdominal malignancy. A probable diagnosis of segmental overgrowth syndrome was made with associated café au laits. We wanted to rule out syndromic cause for the same, so patient was advised clinical whole exome sequencing. Genetic result revealed atypical NF1 with heterogenous 3’ splice site variation in intron 36 of the NF1 gene. We hereby report rare presentation of neurofibromatosis as segmental overgrowth syndrome.