BACKGROUND: Our study addresses the lack of consensus on measuring leg length discrepancy (LLD) after total hip arthroplasty (THA). We will assess the inter-observer variability and correlation between the five most commonly used LLD methods and investigate the use of trigonometric principles in overcoming the limitations of current techniques.
METHODS: LLD was measured on postoperative AP pelvic radiographs using five conventional methods. CT images created a 3D computer model of the pelvis and femur. The resulting models were projected onto a 2D, used to measure LLD by the five methods. The measurements were evaluated via Taguchi analysis, a statistical method identifying the process\'s most influential factors. The approach was used to assess the new trigonometric method.
RESULTS: Conventional methods demonstrated poor correlation. Methods referenced to the centers of the femoral heads were insensitive to LLD originating outside the acetabular cup. Methods referencing either the inter-ischial line or the inter-obturator foramina to the lesser trochanter were sensitive to acetabular and femoral components. Trigonometry-based measurements showed a higher correlation.
CONCLUSIONS: Our results underscore clinicians\' need to specify the methods used to assess LLD. Applying trigonometric principles was shown to be accurate and reliable, but it was contingent on proper radiographic alignment.

UNASSIGNED: Systematic review and meta-analysis to examine common static postural parameters between participants with and without low back pain (LBP).
UNASSIGNED: Systematic search on the PubMed, CINAHL, Embase and SCOPUS databases using keywords \'posture\' and \'low back pain\'. Observational studies comparing static postural outcomes (e.g. lumbar lordosis) between participants with and without LBP were included. Two independent reviewers conducted screening, data extraction and quality assessment. Methodological quality was assessed using Joanna Briggs Institute\'s critical appraisal tools.
UNASSIGNED: Studies included in review = 46 (5,097 LBP; 6,974 controls); meta-analysis = 36 (3,617 LBP; 4,323 controls). Quality of included studies was mixed. Pelvic tilt was statistically significantly higher in participants with LBP compared to controls (n = 23; 2,540 LBP; 3,090 controls; SMD:0.23, 95%CI:0.10,0.35, p < 0.01, I2=72%). Lumbar lordosis and sacral slope may be lower in participants with LBP; pelvic incidence may be higher in this group; both were not statistically significant and the between study heterogeneity was high. Thoracic kyphosis and leg length discrepancy showed no difference between groups.
UNASSIGNED: Lumbopelvic mechanisms may be altered in people with LBP, but no firm conclusions could be made. Pelvic tilt appeared to be increased in participants with LBP. Postural variable measurement needs standardisation. Better reporting of study characteristics is warranted.Implications for rehabilitationLumbo pelvic parameters especially pelvic tilt may be altered in people with low back pain, although no firm conclusion could be made due to the high heterogeneity between studies.Postural assessment within low back pain rehabilitation may therefore require an individualistic approach.

Restoration of equal leg lengths is essential when performing total hip arthroplasty. Pre-operatively, surgeons should assess leg length discrepancy (LLD) on plain radiographs to help adequately plan their operation. Often the hips are in a minor windswept position on radiographs and this can make assessing LLD unreliable. We have devised a simple method for assessing LLD on plain radiographs in patients with windswept hips.

Developmental dysplasia of the hip (DDH) is a serious condition resulting in inadequate acetabular development, distorted bone configuration, and substantially altered hip biomechanics. An extensive leg length discrepancy (LLD) is commonly encountered in such cases, making a total hip arthroplasty (THA) procedure extremely challenging. Although good results in terms of patients\' satisfaction, implant survival rates and overall improved quality of life have been reported, complication rates are considerably higher than primary THA procedures performed for idiopathic osteoarthritis. Reconstructing a dysplastic hip arthrosis and equalizing a preexisting LLD is a technically demanding procedure that is associated with significant bone and soft tissue complications. Intramedullary lengthening through motorized nails has become increasingly popular to address difficult cases with extensive LLD following THA in recent years. However, limited data on femoral lengthening procedures implemented following THA are available considering complications, radiological results, and patient-reported outcomes following staged THA and subsequent femoral lengthening using a femoral magnetically-driven intramedullary lengthening nail. We performed a literature review of the past 10 years in PubMed using the terms neglected hip dislocation, DDH, THA, and intramedullary lengthening nail as keywords. A total amount of eight cases addressing LLD through a telescoping intramedullary nail following THA in DDH have been reported in recent literature. All eight patients underwent primary THA for DDH followed by the implantation of the intramedullary lengthening nail. The mean THA was lengthened by 28.9 mm (from 13.0 to 45.0). The mean time for nail implantation after THA was 11.1 months (from 3.5 to 21). The mean time for lengthening per day through the nail was 0.94 mm (from 0.65 to 1.0) from 26 days to 70 days, and the mean lengthening through the nail was 37.6 mm (from 24.0 to 70.0). Good union and consolidation rates were reported by the authors, while there were no complications. The intramedullary distraction osteogenesis method with a telescopic rod can be an effective method to manage leg length discrepancies while avoiding soft tissue complications in challenging cases of DDH.

BACKGROUND: We created a Multicenter Survey for Italian orthopedics surgeons on how they approach leg length discrepancy when dealing with primary total hip arthroplasty. Aim of the study was to show how surgeons manage LLD and follow literature recommendations during clinical practice.
METHODS: The Survey was composed of 25 questions divided in 4 sections: surgeon\'s profile, preoperative and intraoperative evaluation, postoperative management. In this paper, we report the absolute and relative frequencies of answers to section on \"postoperative management.\" Then, regarding the treatment of residual LLD, we reported whether trauma surgeons and experts in replacement surgery had higher odds ratios for providing \"literature-based\" answers compared to orthopedics physicians.
RESULTS: Only four questions received more than 70% agreement on one of the answers. The OR for giving the \"literature-based\" answer, taking OP as the reference group was 1.57 for TR and 1.72 for RS for 10 mm LLD at first follow-up (FU) and 1.23 TR and 1.32 RS when 20 mm. When 10 mm LLD at 3 months FU the OR was 0.88 TR and 1.15 RS. The OR for treatment of LLD after the first examination of a new patient was 2.16 TR and 1.85 RS.
CONCLUSIONS: LLD is a debated topic with no definitive recommendations. Many decisions still depend on tradition. Treatment of LLD during clinical practice often differs from literature recommendations.

UNASSIGNED: Leg length discrepancy (LLD) is a common complication following total hip arthroplasty (THA). The direct anterior approach (DAA) for THA is gaining popularity due to its advantages, but there is limited research on the incidence and size of LLD. This systematic review aims to explore the differences in LLD between DAA and other approaches, as well as the techniques to control LLD in DAA.
UNASSIGNED: A comprehensive literature search was conducted to identify relevant studies comparing THA by DAA with other surgical approaches and investigating methods to control LLD in DAA, following PRISMA guidelines and a priori registration on PROSPERO (CRD42023412644). The quality of the included studies was assessed. Data on preoperative and postoperative LLD and other relevant outcomes were extracted and analyzed descriptively.
UNASSIGNED: In total, 29 studies were included in this systematic review. The majority (86%) were classified as level IV evidence. Comparisons between DAA and posterior approach (PA) or anterolateral approach (ALA) showed DAA had lower rates of LLD >10 mm compared to PA and ALA. Different pre- and intra-operative techniques were evaluated, but no consensus on the best method for preventing LLD in DAA was reached.
UNASSIGNED: DAA shows comparable or superior results in the prevention of LLD compared to other surgical approaches. Supine patient placement, direct leg measurement, and the use of IF contribute to these outcomes. Intraoperative fluoroscopy with a grid and preoperative planning offers a good option, especially for training purposes, but its role in preventing LLD by experienced DAA surgeons needs further investigation.

OBJECTIVE: Leg length discrepancy (LLD) and lower extremity malalignment can lead to pain and osteoarthritis. A variety of radiographic parameters are used to assess LLD and alignment. A 510(k) FDA approved artificial intelligence (AI) software locates landmarks on full leg standing radiographs and performs several measurements. The objective of this study was to assess the reliability of this AI tool compared to three manual readers.
METHODS: A sample of 320 legs was used. Three readers\' measurements were compared to AI output for hip-knee-angle (HKA), anatomical-tibiofemoral angle (aTFA), anatomical-mechanical-axis angle (AMA), joint-line-convergence angle (JLCA), mechanical-lateral-proximal-femur-angle (mLPFA), mechanical-lateral-distal-femur-angle (mLDFA), mechanical-medial-proximal-tibia-angle (mMPTA), mechanical-lateral-distal-tibia- angle (mLDTA), femur length, tibia length, full leg length, leg-length-discrepancy (LLD), and mechanical-axis-deviation (MAD). Intraclass correlation coefficients (ICCs) and Bland-Altman analysis were used to track performance.
RESULTS: AI output was successfully produced for 272/320 legs in the study. The reader versus AI pairwise ICCs were mostly in the excellent range: 12/13, 12/13, and 9/13 variables were in the excellent range (ICC > 0.75) for readers 1, 2, and 3, respectively. There was better agreement for leg length, femur length, tibia length, LLD, and HKA than for other variables. The median reading times for the three readers and AI were 250, 282, 236, and 38 s, respectively.
CONCLUSIONS: This study showed that AI-based software provides reliable assessment of LLD and lower extremity alignment with substantial time savings.

The aim of this study is to comprehensively investigate the recent literature on the management of leg length discrepancy (LLD). A thorough search of pertinent databases was done in order to find studies that satisfied the requirements for inclusion. A thorough search of PubMed, Web of Science, Scopus, and Science Direct was conducted to find pertinent literature. Rayyan Qatar Computing Research Institute (QRCI, Ar Rayyan, Qatar) was utilized during the whole operation. Eight studies, including a total of 345 patients, were included in our data, and 206 (59.7%) of them were males. Percutaneous epiphysiodesis was the surgical intervention of choice in four studies. LLD can be effectively corrected by temporary and permanent epiphysiodesis. One study reported the incidence of angular deformities following temporary epiphysiodesis. Circumferential periosteal and dual tension-band plating significantly reduced LLD, but reported the incidence of an \"over-shoot\" in some patients. Bilateral motion control shoes and orthotic insole both were found to improve the patient\'s gait and trunk symmetry, evidenced by longer and faster steps, reduced ground impact at heel strike, and lower peak plantar pressure in both limbs. Our findings confirm that no inferences about the superiority of a particular management approach for the treatment of LLD can be made. The poor quality of the studies shows that more randomized control trials and prospective studies on the subject are required.

BACKGROUND: We created a multicenter survey for Italian orthopedic surgeons on how they approach leg length discrepancy (LLD) when dealing with primary total hip arthroplasty. Aim of the study was to show how surgeons manage LLD and follow the literature recommendations during clinical practice.
METHODS: The survey was composed of 25 questions divided into four sections: 1-surgeon\'s profile, 2-preoperative and 3-intraoperative evaluation, and 4-postoperative management. In this paper, we report results to answer Sects. 1 and 2. Absolute and relative frequencies of answers to Sects. 2 and 3 are reported. We divided the participants in subgroups based on the \"surgeon\'s profile\" and evaluated difference in the answers given.
RESULTS: Absolute and relative frequencies demonstrate low agreement among participants in all phases of LLD management. We demonstrated a statistically significant difference based on the surgeon\'s profile regarding these questions: radiographic measure of LLD depending on working experience, p = 0.008; digital planning based on surgeons\' age, p < 0.001, and workplace, p = 0.026; intraoperative anatomical landmarks based on numbers of procedures per year, p = 0.020; and use of intraoperative X-rays based on working experience, p = 0.002.
CONCLUSIONS: LLD is a debated topic with no definitive recommendations. Many decisions still depend on tradition and surgeons\' preference.

UNASSIGNED: Genu recurvatum deformity after treatment of leg-length discrepancy (LLD) with tension-band plating is a recognized, but poorly described phenomenon in medical literature. The aim of this study was to evaluate clinical and radiological features of patients treated with tension-band plating for LLD assessing the development of a recurvatum deformity and its relationship to plate and screw disposition in a transversal plane, thus attempting to establish optimal plate positioning.
UNASSIGNED: Retrospective study of children with LLD treated with tension-band plating. Primary endpoints were clinical and radiological knee recurvatum and anterior and posterior physeal areas measured drawing a line spanning from the lateral to the medial tension-band plates in the transverse plane using volumetric magnetic resonance imaging (vMRI). These findings were compared between patients with and without knee recurvatum.
UNASSIGNED: Twelve children (mean age 11.7 years) were included. Average follow-up was 2.6 years (1.5-5.0). Tension-band plating led to a significant reduction in LLD (mean, 15 mm). Six patients (50 %) developed clinical genu recurvatum (mean, 22°). According to vMRI, patients with genu recurvatum had a larger posterior to anterior physeal area ratio in both distal femur (1.6 versus 0.9, p < 0.05) and proximal tibial physes (2.2 versus 1.0, p < 0.05).
UNASSIGNED: The optimal position of the tension-band plates in distal femoral and proximal tibial physes should be in a point where a posterior to anterior physeal areas ratio is around 1.0, so as to achieve an even distribution of the physeal areas in the multidimensional physeal transverse plane. This point anatomically corresponds in the sagittal X-ray view to an imaginary line located just anterior to the posterior diaphyseal cortical bone on a true lateral radiograph for both femur and tibia.