Aims. Leg length discrepancy (LLD) is a common pre- and postoperative issue in total hip arthroplasty (THA) patients. The conventional technique for measuring LLD has historically been on a non-weightbearing anteroposterior pelvic radiograph; however, this does not capture many potential sources of LLD. The aim of this study was to determine if long-limb EOS radiology can provide a more reproducible and holistic measurement of LLD. Methods. In all, 93 patients who underwent a THA received a standardized preoperative EOS scan, anteroposterior (AP) radiograph, and clinical LLD assessment. Overall, 13 measurements were taken along both anatomical and functional axes and measured twice by an orthopaedic fellow and surgical planning engineer to calculate intraoperator reproducibility and correlations between measurements. Results. Strong correlations were observed for all EOS measurements (r. s. > 0.9). The strongest correlation with AP radiograph (inter-teardrop line) was observed for functional-ASIS-to-floor (functional) (r. s. = 0.57), much weaker than the correlations between EOS measurements. ASIS-to-ankle measurements exhibited a high correlation to other linear measurements and the highest ICC (r. s. = 0.97). Using anterior superior iliac spine (ASIS)-to-ankle, 33% of patients had an absolute LLD of greater than 10 mm, which was statistically different from the inter-teardrop LLD measurement (p < 0.005). Discussion. We found that the conventional measurement of LLD on AP pelvic radiograph does not correlate well with long leg measurements and may not provide a true appreciation of LLD. ASIS-to-ankle demonstrated improved detection of potential LLD than other EOS and radiograph measurements. Full length, functional imaging methods may become the new gold standard to measure LLD. Cite this article: Bone Jt Open 2022;3(12):960–968

Aims. Perthes’ disease (PD) often results in femoral head deformity and leg length discrepancy (LLD). Our objective was to analyze femoral morphology in PD patients at skeletal maturity to assess where the LLD originates, and evaluate the effect of contralateral epiphysiodesis for length equalization on proximal and subtrochanteric femoral lengths. Methods. All patients treated for PD in our institution between January 2013 and June 2020 were reviewed retrospectively. Patients with unilateral PD, LLD of ≥ 5 mm, and long-leg standing radiographs at skeletal maturity were included. Total leg length, femoral and tibial length, articulotrochanteric distance (ATD), and subtrochanteric femoral length were compared between PD side and the unaffected side. Furthermore, we compared leg length measurements between patients who did and who did not have a contralateral epiphysiodesis. Results. Overall, 79 patients were included, of whom 21 underwent contralateral epiphysiodesis for leg length correction. In the complete cohort, the mean LLD was 1.8 cm (95% confidence interval (CI) 1.5 to 2.0), mean ATD difference was 1.8 cm (95% CI -2.1 to -1.9), and mean subtrochanteric difference was -0.2 cm (95% CI -0.4 to 0.1). In the epiphysiodesis group, the mean LLD before epiphysiodesis was 2.7 cm (95% CI 1.3 to 3.4) and 1.3 cm (95% CI -0.5 to 3.8) at skeletal maturity. In the nonepiphysiodesis group the mean LLD was 2.0 cm (95% CI 0.5 to 5.1; p = 0.016). The subtrochanteric region on the PD side was significantly longer at skeletal maturity in the epiphysiodesis group compared to the nonepiphysiodesis group (-1.0 cm (95% CI -2.4 to 0.6) vs 0.1 cm (95% CI -1.0 to 2.1); p < 0.001). Conclusion. This study demonstrates that LLD after PD originates from the proximal segment only. In patients who had contralateral epiphysiodesis to balance leg length, this is achieved by creating a difference in subtrochanteric length. Arthroplasty surgeons need to be aware that shortening of the proximal femur segment in PD patients may be misleading, as the ipsilateral subtrochanteric length in these patients can be longer. Therefore, we strongly advise long-leg standing films for THA planning in PD patients in order to avoid inadvertently lengthening the limb. Cite this article: Bone Joint J 2021;103-B(11):1736–1741

Aims

This study aimed to investigate the incidence of ≥ 5 mm asymmetry in lower and whole leg lengths (LLs) in patients with unilateral osteoarthritis (OA) secondary to developmental dysplasia of the hip (DDH-OA) and primary hip osteoarthritis (PHOA), and the relationship between lower and whole LL asymmetries and femoral length asymmetry.

Aims. To evaluate mid-to long-term patient-reported outcome measures (PROMs) of endoprosthetic reconstruction after resection of malignant tumours arising around the knee, and to investigate the risk factors for unfavourable PROMs. Methods. The medical records of 75 patients who underwent surgery between 2000 and 2020 were retrospectively reviewed, and 44 patients who were alive and available for follow-up (at a mean of 9.7 years postoperatively) were included in the study. Leg length discrepancy was measured on whole-leg radiographs, and functional assessment was performed with PROMs (Toronto Extremity Salvage Score (TESS) and Comprehensive Outcome Measure for Musculoskeletal Oncology Lower Extremity (COMMON-LE)) with two different aspects. The thresholds for unfavourable PROMs were determined using anchor questions regarding satisfaction, and the risk factors for unfavourable PROMs were investigated. Results. The thresholds for favourable TESS and COMMON were 64.8 and 70.4 points, respectively. Multivariate analysis showed that age at surgery (p = 0.004) and postoperative leg length discrepancy (p = 0.043) were significant risk factors for unfavourable TESS results, while age at surgery (p < 0.001) was a significant risk factor for unfavourable COMMON-LE results. Following receiver operating characteristic analysis, the threshold for both TESS and COMMON-LE was 29 years of age at surgery. Additionally, a leg length discrepancy of 8.2 mm was the threshold for unfavourable TESS. Conclusion. Patients aged > 29 years at the time of surgery require appropriate preoperative counselling and adequate postoperative physical and socioemotional support. Reconstruction equivalent to the length of the resected bone can reduce the risk of functional disabilities in daily living. Cite this article: Bone Jt Open 2023;4(12):906–913

Originally used for correction of angular malalignment, 2 hole plate epiphyseodesis has recently gained popularity in paediatric orthopaedic practice for the correction of leg length discrepancy. In this study we aim to assess the efficiency of guided growth plates in correcting leg length discrepancy. Thirty-three children treated for leg length discrepancy with guided growth plates (“8-Plate”, Orthofix, Inc and “I-Plate”, Orthopediatrics) in a tertiary referral centre were retrospectively analysed. Medial and Lateral plates were inserted for symmetrical growth reduction and patients were followed up with clinical and radiological assessment. Thirty patients had distal femoral epiphyseodesis and three had proximal tibial epiphyseodesis. Leg lengths and individual bone lengths were measured from pre and post – operative radiographs. The angle between the screws was measured from radiographs taken intra operatively and at the time of final follow up to assess screw divergence with growth. Efficiency was calculated as the ratio of growth inhibition achieved to the projected discrepancy at maturity if left untreated. At a mean follow up of 17 months (4–30 m) leg length discrepancy improved from a mean of 30 mm (50–15mm) to 13 mm (2.5–39mm) (p < 0.01). The angle between screws increased from 6 degrees to 26 degrees over the follow up period. Efficiency was found to be 66%. There were 5 patients with angular deformity who needed plate removal and 2 patients developed superficial infection that responded to oral antibiotics. Epiphyseodesis using guided growth plates is an effective way to correct leg length discrepancy as it is a reversible procedure. Patients undergoing this treatment should be kept under close follow up to prevent development of angular malalignment. Inserting the screws in a divergent fashion at the outset may increase the effectiveness of this procedure

It has been well documented that leg length discrepancy can be associated with back, knee and hip problems. Less is known about the effect on the foot. The effect of a simulated leg length discrepancy on foot loading patterns and gait cycle times in normal individuals was investigated. Thirty feet of normal volunteers were evaluated using a ‘Musgrave Footprint Computerised Pedobarograph System’. Leg length discrepancy was simulated using flexible polyurethane soles of 1 to 5cm thickness, secured to the sole of a sandal worn on the opposite foot. Recordings of foot pressures and load were made barefoot (control) and then recordings were taken with simulated leg length discrepancies of 1 to 5cm. As leg length discrepancy increased, the total loading on the foot increased from 35. 31 to 37. 99 kg/cm²/sec, the forefoot loading increased from 15. 58 to 19 kg/cm²/sec, whereas hindfoot loading remained the same. Further analysis of forefoot loading revealed that all subjects except for female middle loaders demonstrated increased hallux loading as the leg length discrepancy increased (p< 0. 0001). Analysis of gait cycle time with increasing leg length discrepancy showed that the contact phase of gait decreased from a mean of 22% to 13% (p< 0. 0001), the midstance phase remained the same, whereas the propulsion phase increased from 44% to 50% (p< 0. 003). This study demonstrates for the first time that leg length discrepancy has manifest changes in the foot. When prescribing orthotics to address leg length discrepancy, orthopaedic surgeons should consider attempts to relieve the increased pressure on the 2nd and 3d metatarsal heads, or incorporate a metatarsal bar to decrease the time of metatarsal loading

Digital templating was used in 50 patients who underwent THA using Merge Ortho software, Cedara. Clinical examination was performed first, to measure leg lengths and account for pelvic obliquity and flexion deformity. Good quality digital radiographs were obtained with anteroposterior and lateral views extending beyond the tip of the femoral component and the cement restrictor. A coin was placed on the ASIS to help in determining radiological magnification. Digital radiographs were saved in DICOM format and imported to EndoMap software system. A 6-step technique was used for templating as follows:. Radiographic assessment; looking at the quality of bone, amount of bone stock, dysplasia, osteophytes, and other abnormalities. Correction of magnification; following the specific instructions of the software, by measuring the diameter of the coin on the digital radiograph. 3. Measuring leg length discrepancy; the software system automatically calculated the leg length discrepancy, even in the presence of pelvic obliquity (Figure1). 4. Templating acetabular component; the desired cup was selected from the implant library after identifying important landmarks. The size and position was modified to fit the acetabulum and to restore the center of rotation of the hip, considering minimal bone removal and sufficient bone coverage laterally. Templating femoral component; the size and position of the desired stem was adjusted to fit the femoral canal, different offsets were compared to find the best match for the patient's original offset. Correction of leg length discrepancy and measuring length of neck resection; the height of the femoral stem was adjusted to correct any leg length discrepancy by placing the center of the head above the center of the cup by the same length of discrepancy. Then the level of the neck resection was marked at the level of the stem collar and the femoral neck cut was measured by a digital ruler from the tip of the lesser trochanter to the mark of neck resection. In case of leg length discrepancy, the height of the femoral neck cut was adjusted accordingly to compensate for the leg length discrepancy. For example, if the affected leg is 20 mm short, place the centre of the head 20 mm above the centre of the cup. Intraoperatively, the surgeon performed the femoral neck osteotomy at the level determined by preoperative templating. Postoperatively, the leg length was measured and compared to the preoperative leg length. Preoperatively, the leg length discrepancy ranged from 5 to 30 mm. In all cases, the leg was short on the side of THR (ipsilateral). Leg length discrepancy was adjusted in all THR cases. Postoperatively, the accuracy of the correction was found to be within 5 millimeters i.e. less than 5mm of shortening or lengthening). Intraoperatively, the level of femoral neck cut ranged from 1 to 44 mm. Digital templating is useful in adjusting leg length discrepancy. In addition, there were other benefits such as predication of femoral and acetabular implant sizes, restoration of normal hip centre, and optimization of femoral offset

The Dall approach is a modified anterolateral approach with osteotomy of the anterior part of the greater trochanter. This approach relatively preserves the soft tissue tension during total hip arthroplasty (THA). We insert the stem and select a ball neck size so as to have a stable hip which will not dislocate easily during the trial reduction. The aim of this study is to evaluate the adequacy of this method, to measure leg length discrepancy and offset discrepancy at postoperative radiographs. We selected patients for inclusion in this study from those who have more than a 120 degree of affected hip flection angle, the opposite hip is almost normal with a low leg length discrepancy (primary OA, osteonecrosis, Crowe 1 secondary OA, femoral neck fracture). All THA were performed with cement fixation using an alignment guide to ensure accurate acetabular positioning. The ball head's diameter used were all 26mm. From September 2011 to October 2013, 22 patients met inclusion criteria among 103 THA. The mean age for 22 subjects was 66.6±12 years. The mean flexion angle of preoperative hip joints was 127.2±6.1 degrees. The cup inclination was 43.8° ± 3.5°. Anteversion was 11.8°±6°. The mean preoperative leg length discrepancy was 5.8mm±6.3mm. The mean postoperative leg length discrepancy was 0.7±3.5mm. The mean postoperative offset discrepancy was 0.7±6.6mm. There were no dislocations in this series of 103 cases. Discussion. Dislocation and leg length discrepancies are major complications following a total hip arthroplasty. A good range of motion of the preoperative hip joint is considered a high risk dislocation factor. The Dall approach with minimal release of soft tissue related to a tension of hip joint offers maximal stability and the ability to accurately restore leg length

Purpose of the study: Perception of leg length discrepancy after total hip arthroplasty (THA) is a source of patient dissatisfaction. We followed 100 patients with firstintention THA to determine the clinical significance of radiological leg length discrepancy of less than 15 mm. Materials and Methods: An investigator blinded to the clinical context measured radiological leg length discrepancy in 100 patients after THA. Another investigator evaluated the clinical perception of leg length discrepancy in the same patients 15 days, one month, three months and one year after implantation of their THA. Results: At 15 days, 73 patients had a clinical perception of leg length discrepancy; 48 at one month; 24 at three months; and 15 at one year. Although the 15 patients (15%) presented leg length discrepancy greater than 10 mm (but less than 15 mm), only four still perceived this difference at one year. At one year, there was no correlation between the length of the discrepancy and clinical perception by the patient. When patients had a length discrepancy greater than 10 mm (but less than 15 mm), the probability of perceiving the difference clinically was not greater (p> 0.05) than for patients whose leg length discrepancy was less than 10 mm. Conversely, patients who perceived a leg length discrepancy at one year had significantly more pronounced (p=0.02) spinal disorders and more permanent hip flexion. Discussion: Perception of leg length discrepancy is a frequent complaint postoperatively, but rare at one year, even when the radiological difference reaches 15 mm. At one year, the perception of leg length discrepancy is not correlated with the radiological difference but rather with the degree of spinal disorder or permanent hip flexion. Conclusion: Navigation would have a modest effect on this problem which is probably related in part to spinal rehabilitation

Aims. To evaluate if, for orthopaedic trainees, additional cadaveric simulation training or standard training alone yields superior radiological and clinical outcomes in patients undergoing dynamic hip screw (DHS) fixation or hemiarthroplasty for hip fracture. Methods. This was a preliminary, pragmatic, multicentre, parallel group randomized controlled trial in nine secondary and tertiary NHS hospitals in England. Researchers were blinded to group allocation. Overall, 40 trainees in the West Midlands were eligible: 33 agreed to take part and were randomized, five withdrew after randomization, 13 were allocated cadaveric training, and 15 were allocated standard training. The intervention was an additional two-day cadaveric simulation course. The control group received standard on-the-job training. Primary outcome was implant position on the postoperative radiograph: tip-apex distance (mm) (DHS) and leg length discrepancy (mm) (hemiarthroplasty). Secondary clinical outcomes were procedure time, length of hospital stay, acute postoperative complication rate, and 12-month mortality. Procedure-specific secondary outcomes were intraoperative radiation dose (for DHS) and postoperative blood transfusion requirement (hemiarthroplasty). Results. Eight female (29%) and 20 male trainees (71%), mean age 29.4 years, performed 317 DHS operations and 243 hemiarthroplasties during ten months of follow-up. Primary analysis was a random effect model with surgeon-level fixed effects of patient condition, patient age, and surgeon experience, with a random intercept for surgeon. Under the intention-to-treat principle, for hemiarthroplasty there was better implant position in favour of cadaveric training, measured by leg length discrepancy ≤ 10 mm (odds ratio (OR) 4.08 (95% confidence interval (CI) 1.17 to 14.22); p = 0.027). There were significantly fewer postoperative blood transfusions required in patients undergoing hemiarthroplasty by cadaveric-trained compared to standard-trained surgeons (OR 6.00 (95% CI 1.83 to 19.69); p = 0.003). For DHS, there was no significant between-group difference in implant position as measured by tip-apex distance ≤ 25 mm (OR 6.47 (95% CI 0.97 to 43.05); p = 0.053). No between-group differences were observed for any secondary clinical outcomes. Conclusion. Trainees randomized to additional cadaveric training performed hip fracture fixation with better implant positioning and fewer postoperative blood transfusions in hemiarthroplasty. This effect, which was previously unknown, may be a consequence of the intervention. Further study is required. Cite this article: Bone Jt Open 2023;4(8):602–611

Aims: Leg length discrepancy is a well-recognised complication after total hip arthroplasty. However, the effect of using a cemented or uncemented femoral component on leg length has not been previously investigated. The aim of our study was to assess leg length discrepancy following total hip arthroplasty using a cemented femoral component and to compare this with an uncemented femoral component. Patients and method: We included 140 patients who had undergone a primary total hip arthroplasty in our study. All patients received an uncemented Duraloc acetabular cup (Depuy, Leeds, UK). Our uncemented group consisted of 70 consecutive patients who had received an uncemented Accolade femoral prosthesis (Depuy, Leeds, UK). Our cemented group included 70 patients who had received a cemented Ultima femoral prosthesis (Depuy, Leeds, UK). Leg lengths were measured from radiographs by two independent observers using a validated assessment method, pre-operatively and at six months post-operatively. Clinical outcome was assessed using Harris hip scores. Results: The mean age of the patients was 68 years for the uncemented group and 56 years for the cemented group. The overall leg length discrepancy was mean 5.7mm (range 0 to 26mm). The uncemented group had an increase in leg length discrepancy post-operatively compared to the cemented group (6.4mm vs 4.2mm), p< 0.05. There was no significant difference in Harris hip scores between the uncemented and cemented groups either pre-operatively (37.4 vs 38.7) or at 6 months postoperatively (77.9 vs 78.7 respectively). Conclusion: We found a significant increase in leg length discrepancy after total hip arthroplasty using an uncemented femoral prosthesis compared with a cemented femoral prosthesis. This was detectable radiologically but did not affect clinical outcome. Patients should be informed about the risk of leg length discrepancy before total hip arthroplasty particularly if an uncemented femoral prosthesis is used

Our aim was to use CT Scanogram to evaluate fibular growth, and thus calculate normal growth velocity, which may aid in determining the timing of epiphysiodesis. Current understanding of normal lower limb growth and growth prediction originates in the work of Anderson et al published in the 1960s. There now exist several clinical and mathematical methods to aid in the treatment of leg length discrepancy, including the timing of epiphysiodesis. Early research in this area provided limited information on the growth of the fibula. It is now well recognized that abnormal growth of paired long bones may evolve into deformity of clinical significance. Existing work examining fibular growth used plain film radiography only. Computed Tomography (CT) scanogram is now the preferred method for evaluating leg length discrepancy in the paediatric population. We calculated fibular growth for 28 children (n = 28, 16 girls and 12 boys) presenting with leg length discrepancy to our unit. Mean age at presentation was 111.1 months (range 33 – 155 months). For inclusion, each child had to have at least five CT scanograms performed, at six monthly intervals. Fibular length was calculated digitally as the distance from the proximal edge of the proximal epiphysis to the most distal edge of the distal epiphysis. For calculation purposes, mean fibular length was determined from two measurements taken of the fibula. A graph for annual fibular growth was plotted and fibular growth velocity calculated. CT Scanogram may be used to calculate normal fibular growth in children presenting with leg length discrepancy

The February 2023 Children’s orthopaedics Roundup. 360. looks at: Trends in management of paediatric distal radius buckle fractures; Pelvic osteotomy in patients with previous sacral-alar-iliac fixation; Sacral-alar-iliac fixation in patients with previous pelvic osteotomy; Idiopathic toe walking: an update on natural history, diagnosis, and treatment; A prediction model for treatment decisions in distal radial physeal injuries: a multicentre retrospective study; Angular deformities after percutaneous epiphysiodesis for leg length discrepancy; MRI assessment of anterior coverage is predictive of future radiological coverage; Predictive scoring for recurrent patellar instability after a first-time patellar dislocation

Aims. As an alternative to external fixators, intramedullary lengthening nails (ILNs) can be employed for distraction osteogenesis. While previous studies have demonstrated that typical complications of external devices, such as soft-tissue tethering, and pin site infection can be avoided with ILNs, there is a lack of studies that exclusively investigated tibial distraction osteogenesis with motorized ILNs inserted via an antegrade approach. Methods. A total of 58 patients (median age 17 years (interquartile range (IQR) 15 to 21)) treated by unilateral tibial distraction osteogenesis for a median leg length discrepancy of 41 mm (IQR 34 to 53), and nine patients with disproportionate short stature treated by bilateral simultaneous tibial distraction osteogenesis, with magnetically controlled motorized ILNs inserted via an antegrade approach, were retrospectively analyzed. The median follow-up was 37 months (IQR 30 to 51). Outcome measurements were accuracy, precision, reliability, bone healing, complications, and patient-reported outcome assessed by the Limb Deformity-Scoliosis Research Society Score (LD-SRS-30). Results. A median tibial distraction of 44 mm (IQR 31 to 49) was achieved with a mean distraction index of 0.5 mm/day (standard deviation 0.13) and median consolidation index of 41.2 days/cm (IQR 34 to 51). Accuracy, precision, and reliability were 91%, 92%, and 97%, respectively. New temporary range of motion limitations occurred in 51% of segments (34/67). Distraction-related equinus deformity treated by Achilles tendon lengthening was the most common major complication recorded in 16% of segments (11/67). In 95% of patients (55/58) the distraction goal was achieved with 42% unplanned additional interventions per segment (28/67). The median postoperative LD-SRS-30 score was 4.0 (IQR 3.6 to 4.3). Conclusion. Tibial distraction osteogenesis using motorized ILNs inserted via an antegrade approach appears to be a reliable and precise procedure. Temporary joint stiffness of the knee or ankle should be expected in up to every second patient. A high rate and wide range of complications of variable severity should be anticipated. Cite this article: Bone Joint J 2024;106-B(3):293–302

We assessed leg length discrepancy and hip function in 90 patients undergoing primary total hip arthroplasty before surgery and at three and 12 months after. Function was measured using the Oxford hip score (OHS). After surgery the mean OHS improved by 26 points after three months and by 30 points after 12. After operation 56 (62%) limbs were long by a mean of 9 mm and this was perceived by 24 (43%) patients after three months and by 18 (33%) after 12. The mean OHS in patients who perceived true lengthening was 27% worse than the rest of the population after three months and 18% worse after 12. In 55 (98%) patients, lengthening occurred in the femoral component. Appropriate placement of the femoral component could significantly reduce a patient’s perception of discrepancy of length

Leg length discrepancy (LLD) is a recognised complication of total hip arthroplasty. LLDs can cause abnormal weight bearing, leading to increased wear, aseptic loosening of replacement hips and pain. To compensate for LLDs the patient can either flex the knee of the long leg or tilt their pelvis. The aim of this project was to investigate how stance affects static limb loading of patients with leg length discrepancy. A pedobarograph was used to measure the limb loading of 20 normal volunteers aged 19 to 60. A 2 second recording with both feet on was taken to establish their body weight. Readings were taken of the left foot with the right level, 3.5cm lower (simulating a long left leg) and 3.5cm higher. In each case three readings were taken with the knee flexed and three readings with the knee extended. When both feet were at the same level, the left limb took 54% of the load. When the right foot was lower and the left knee flexed, the left leg took 39 % of the load (P < 0.001) (paired t-test). When the left knee was extended the left leg took 49 % of the load (P = 0.074). With the right foot higher and right knee flexed, the left leg took 65 % of the load (P < 0.001). When the right knee was extended the left leg took 58 % of the load (P = 0.069). These results show that weight distribution is increased in the simulated shorter limb. Loading is greater when the longer limb is flexed. Tilting the pelvis reduced the load. However this may cause pelvic and spinal problems. Uneven load distribution is likely to lead to early fatigue when standing and may explain why some post arthroplasty patients with limb length discrepancy have poor outcomes

Aims. Pelvic discontinuity is a challenging acetabular defect without a consensus on surgical management. Cup-cage reconstruction is an increasingly used treatment strategy. The present study evaluated implant survival, clinical and radiological outcomes, and complications associated with the cup-cage construct. Methods. We included 53 cup-cage construct (51 patients) implants used for hip revision procedures for pelvic discontinuity between January 2003 and January 2022 in this retrospective review. Mean age at surgery was 71.8 years (50.0 to 92.0; SD 10.3), 43/53 (81.1%) were female, and mean follow-up was 6.4 years (0.02 to 20.0; SD 4.6). Patients were implanted with a Trabecular Metal Revision Shell with either a ZCA cage (n = 12) or a TMARS cage (n = 40, all Zimmer Biomet). Pelvic discontinuity was diagnosed on preoperative radiographs and/or intraoperatively. Kaplan-Meier survival analysis was performed, with failure defined as revision of the cup-cage reconstruction. Results. The five-year all-cause survival for cup-cage reconstruction was 73.4% (95% confidence interval (CI) 61.4 to 85.4), while the ten- and 15-year survival was 63.7% (95% CI 46.8 to 80.6). Survival due to aseptic loosening was 93.4% (95% CI 86.2 to 100.0) at five, ten, and 15 years. The rate of revision for aseptic loosening, infection, and dislocation was 3/53 (5.7%), 7/53 (13.2%), and 6/53 (11.3%), respectively. The mean leg length discrepancy improved (p < 0.001) preoperatively from a mean of 18.2 mm (0 to 80; SD 15.8) to 7.0 mm (0 to 35; SD 9.8) at latest follow-up. The horizontal and vertical hip centres improved (p < 0.001) preoperatively from a mean of 9.2 cm (5.6 to 17.5; SD 2.3) to 10.1 cm (6.2 to 13.4; SD 2.1) and 9.3 cm (4.7 to 15.8; SD 2.5) to 8.0 cm (3.7 to 12.3; SD 1.7), respectively. Conclusion. Cup-cage reconstruction provides acceptable outcomes in the management of pelvic discontinuity. One in four constructs undergo revision within five years, most commonly for periprosthetic joint infection, dislocation, or aseptic loosening. Cite this article: Bone Joint J 2024;106-B(5 Supple B):66–73

Aims. Achieving accurate implant positioning and restoring native hip biomechanics are key surgeon-controlled technical objectives in total hip arthroplasty (THA). The primary objective of this study was to compare the reproducibility of the planned preoperative centre of hip rotation (COR) in patients undergoing robotic arm-assisted THA versus conventional THA. Methods. This prospective randomized controlled trial (RCT) included 60 patients with symptomatic hip osteoarthritis undergoing conventional THA (CO THA) versus robotic arm-assisted THA (RO THA). Patients in both arms underwent pre- and postoperative CT scans, and a patient-specific plan was created using the robotic software. The COR, combined offset, acetabular orientation, and leg length discrepancy were measured on the pre- and postoperative CT scanogram at six weeks following surgery. Results. There were no significant differences for any of the baseline characteristics including spinopelvic mobility. The absolute error for achieving the planned horizontal COR was median 1.4 mm (interquartile range (IQR) 0.87 to 3.42) in RO THA versus 4.3 mm (IQR 3 to 6.8; p < 0.001); vertical COR mean 0.91 mm (SD 0.73) in RO THA versus 2.3 mm (SD 1.3; p < 0.001); and combined offset median 2 mm (IQR 0.97 to 5.45) in RO THA versus 3.9 mm (IQR 2 to 7.9; p = 0.019). Improved accuracy was observed with RO THA in achieving the desired acetabular component positioning (root mean square error for anteversion and inclination was 2.6 and 1.3 vs 8.9 and 5.3, repectively) and leg length (mean 0.6 mm vs 1.4 mm; p < 0.001). Patient-reported outcome measures were comparable between the two groups at baseline and one year. Participants in the RO THA group needed fewer physiotherapy sessions postoperatively (median six (IQR 4.5 to 8) vs eight (IQR 6 to 11; p = 0.005). Conclusion. This RCT suggested that robotic-arm assistance in THA was associated with improved accuracy in restoring the native COR, better preservation of the combined offset, leg length correction, and superior accuracy in achieving the desired acetabular component positioning. Further evaluation through long-term and registry data is necessary to assess whether these findings translate into improved implant survival and functional outcomes. Cite this article: Bone Joint J 2024;106-B(4):324–335

Background. Leg length discrepancy (LLD) after intramedullary nailing of femoral shaft fractures is a common problem reported in up to 43% of cases. Comminuted fractures with radiographic loss of bony landmarks have an increased possibility of being fixed with unequal leg lengths. Aims. The purpose of this report is to evaluate the efficacy of routinely obtaining a CT scanogram post-operatively on patients of comminuted femoral shaft fractures treated with intramedullary nailing and immediate correction of limb length inequality if indicated. Results. Twenty one patients with comminuted femoral shaft fractures that were treated with intramedullary nailing and underwent a CT scannogram for evaluation of LLD were included in the study. There were 12 patients with Winquist III and 9 with a Winquist IV fracture pattern. Following surgery leg lengths were measured from the CT scanograms using a computerised measuring ruler. The largest leg length discrepancy noted on scannogram was 4 cm. The average limb length discrepancy was 0.67 cm. Eight patients had a discrepancy of 1cm or greater. We also measured the tibial length in all patients and found only 3 patients with exactly equal tibial lengths. A tibial length discrepancy less than 5mm was observed in 11 patients. In 7 patients it was between 5-9mm and in 3 patients it was 10mm or greater. Four patients underwent leg length correction during the same admission. Conclusion. The decision to undertake correction of the LLD is primarily dependant on the degree of discrepancy. The degree of LLD that requires correction remains undefined. In this study LLD of greater than 15mm was considered for equalisation. Immediate equalisation saves cost, morbidity, delayed sequelae and litigation. Tibial length discrepancy may contribute to the total leg length discrepancy and requires consideration. We recommend a post-operative scanogram costing $380 in patients of comminuted femoral shaft fractures treated with intramedullary nailing

Aims. The aims of this study were to compare clinically relevant measurements of hip dysplasia on radiographs taken in the supine and standing position, and to compare Hip2Norm software and Picture Archiving and Communication System (PACS)-derived digital radiological measurements. Methods. Preoperative supine and standing radiographs of 36 consecutive patients (43 hips) who underwent periacetabular osteotomy surgery were retrospectively analyzed from a single-centre, two-surgeon cohort. Anterior coverage (AC), posterior coverage (PC), lateral centre-edge angle (LCEA), acetabular inclination (AI), sharp angle (SA), pelvic tilt (PT), retroversion index (RI), femoroepiphyseal acetabular roof (FEAR) index, femoroepiphyseal horizontal angle (FEHA), leg length discrepancy (LLD), and pelvic obliquity (PO) were analyzed using both Hip2Norm software and PACS-derived measurements where applicable. Results. Analysis of supine and standing radiographs resulted in significant variation for measurements of PT (p < 0.001) and AC (p = 0.005). The variation in PT correlated with the variation in AC in a limited number of patients (R. 2. = 0.378; p = 0.012). Conclusion. The significant variation in PT and AC between supine and standing radiographs suggests that it may benefit surgeons to have both radiographs when planning surgical correction of hip dysplasia. We also recommend using PACS-derived measurements of AI and SA due to the poor interobserver error on Hip2Norm. Cite this article: Bone Joint J 2021;103-B(11):1662–1668

Proximal femoral varus osteotomy improves the biomechanics of the hip and can stimulate normal acetabular development in a dysplastic hip. Medial closing wedge osteotomy remains the most popular technique, but is associated with shortening of the ipsilateral femur. We produced a trigonometric formula which may be used pre-operatively to predict the resultant leg length discrepancy (LLD). We retrospectively examined the influence of the choice of angle in a closing wedge femoral osteotomy on LLD in 120 patients (135 osteotomies, 53% male, mean age six years, (3 to 21), 96% caucasian) over a 15-year period (1998 to 2013). A total of 16 of these patients were excluded due to under or over varus correction. The patients were divided into three age groups: paediatric (< 10 years), adolescent (10 to 16 years) and adult (> 16 years). When using the same saw blades as in this series, the results indicated that for each 10° of angle of resection the resultant LLD equates approximately to multiples of 4 mm, 8 mm and 12 mm in the three age groups, respectively. Statistical testing of the 59 patients who had a complete set of pre- and post-operative standing long leg radiographs, revealed a Pearson’s correlation coefficient for predicted versus radiologically observed shortening when using a wedge of either 10° or 20° of 0.93 (p <  0.001). The 95% limits of agreement from the Bland–Altman analysis for this subgroup were –3.5 mm to +3.3 mm. It has been accepted that a 10 mm discrepancy is clinically acceptable. This study identified a geometric model that provided satisfactory accuracy when using specific saw blades of known thicknesses for this formula to be used in clinical practice. Cite this article: Bone Joint J 2014;96-B:1124–9

Over a 25-year period, 12 patients had from 2.5 to 5.1 cm operative shortening of the tibia and fibula for leg length discrepancy at between four and 18 years of age. All recovered normal function and there was minor cosmetic impairment in only two cases. The only vascular complication was temporary delay in return of the circulation to the foot after tourniquet removal in one patient. The procedure is valuable for discrepancy of tibial length in patients when they present too late for epiphyseal arrest, when there is doubt as to the appropriate timing for epiphyseal arrest, or when it is uncertain at an earlier stage whether there is need for surgical correction

In 90 patients undergoing primary THA, leg length discrepancy (LLD) and hip function were assessed pre-operatively and 3 and 12 months postoperatively. Hip function was measured by the Oxford hip score (OHS). Postoperatively the mean OHS improved by 26 points out of a possible 48 at 3 months and by 30 points at 12 months. Postoperatively 62% of patients’ limbs were lengthened by a mean of 9 mm. The LLD was perceived by 43% of the affected patients at 3 months and by 33% at 12 months. The OHS in patients who perceived true lengthening was 27% worse than in the other patients at 3 months and 18% worse at 12 months. In 98%, lengthening occurred in the femoral component. The problem of LLD after THA is lengthening. Appropriate placement of the femoral component could reduce patients’ perception of this

1. A simple calculation for the timing of epiphysial arrest to correct leg length discrepancy is described. An assumption is made that growth ceases at a constant chronological age of sixteen years in boys and fourteen years in girls. It is further assumed that the lower femoral epiphysis provides three-eighths of an inch and the upper tibial epiphysis one-quarter inch of growth each year. 2. Whilst the assumptions made are known to be approximations, analysis of the results of fifty-three epiphysial arrests in forty-four children shows that the errors cancel themselves sufficiently to make this method accurate. The simplicity of the calculation makes it useful to confirm or modify the timing of arrests calculated on the basis of skeletal age, or as an alternative method

Introduction and aims: Leg length discrepancy (LLD) after total hip arthroplasty (THA) has been associated with a number of complications. The aim of this study was to assess the influence of LLD on the outcome of THA by comparing patients’ perception and their Oxford Hip Score with their anatomical leg length. A secondary aim was to identify the site at which LLD was created intraoperatively. Methods: LLD and hip function were assessed in 90 patients undergoing primary total hip arthroplasty before and 3 months after surgery. Hip function was measured by the Oxford Hip Score (OHS). We measured leg length on pre- and postoperative radiographs and the position of the centre of rotation and the stem length on the postoperative radiographs. Results: Post operatively 62% of patients’ limbs were lengthened by a mean of 9 mm. This was perceived by 43% of the lengthened patients. The OHS in patients who perceived true lengthening was 27% worse than the rest of the population. In 98%, lengthening occurred in the femoral component. 20% perceived true shortening and their OHS was not affected. Conclusion: The problem of LLD after THA is lengthening. Accurate placement of the femoral component and especially avoiding overlengthening could significantly reduce patients’ perception of this

Objectives: We aimed to assess the incidence of requirement for shoe raises for a leg length discrepancy (LLD) after total hip replacement (THR). We also assessed the patient satisfaction with, and continued use of shoe raises for symptomatic LLD after THR. Methods: We searched the orthotics records at our institution to identify all patients who had required a shoe raise for symptomatic LLD after primary unilateral total hip replacement between January 2003 and October 2008. 75 patients were identified. 72 were still alive. In the same period 4270 primary hip replacements were carried out at the institution. A questionnaire was sent out to all living patients. Patient details (including satisfaction) and operative details were recorded. Pre-operative and post-operative radiological measurements of leg length discrepancy (LLD) were performed. Results: The incidence of requirement of a shoe raise for LLD after THR at our institution was 1.8%. 68% were women. 84% of questionnaires were returned. 31% had stopped using their shoe raise completely. Two-thirds of patients found the raise improved their symptoms of a LLD. Symptoms causing dissatisfaction with the shoe raise included new or worsening back pain, limp, uneven walking, self awareness, need to adjust trouser length, pain in other hip, discomfort while walking, and difficulty buying shoes. Patient overall satisfaction with their THR was poor in the patients who were dissatisfied with the shoe raise, but was good in those who found the raise useful. Conclusion: About 2% of patients may require a shoe raise for symptomatic LLD after THR. Of these 65% will find the shoe raise helpful. Patient with a LLD after a THR that is not helped by a shoe raise are very dissatisfied. It is important that surgeons should take great care to avoid causing a LLD after THR as it can be a cause of very low patient satisfaction

Introduction. Many authors have described component position and leg length discrepancy (LLD) after total hip arthroplasty (THA) as the most important factors for good postoperative outcomes. However, regarding the relationships between component position and different approaches for THA, the optimal approach for component position and LLD remains unknown. The aims of this study were to compare these factors among the direct anterior, posterolateral, and direct lateral approaches on postoperative radiographs retrospectively, and determine which approach leads to good orientation in THA. Methods. We retrospectively evaluated 150 patients who underwent unilateral primary THA in our department between January 2009 and December 2014, with the direct anterior, posterolateral, or direct lateral approach used in 50 patients each. Patients with significant hip dysplasia (Crowe 3 or 4), advanced erosive arthritis, prevented osteotomy of the contralateral hip, and body mass index (BMI) of more than 30 were excluded. The mean age, sex, and preoperative diagnosis of the affected hip were equally distributed in patients who underwent THA with the different approaches. The mean BMI did not differ significantly among the groups. The radiographic measurements included cup inclination angle, dispersion of cup inclination from 40°, and LLD on an anteroposterior pelvic radiograph, and cup anteversion angle and dispersion of cup anteversion from 20° on a cross-table lateral radiograph postoperatively. We also measured the ratios of patients with both cup inclination of 30–50° and cup anteversion of 10–30° (target zone in our department), femoral stem varus/valgus, and LLD of 10 mm or less. Statistical analyses used an unpaired t-test and Fisher's exact test, with significance set at p<0.05. Results. The mean cup inclination was 36.9±5.1° for direct anterior approach, 40.8±7.5° for posterolateral approach, and 38.5±7.5° for direct lateral approach. Dispersion of cup inclination from 40° was almost identical in the three groups, with no significant differences. The mean cup anteversion was 23.4±5.5° for direct anterior approach, 25.9±9.2° for posterolateral approach, and 24.3±8.6° for direct lateral approach. Dispersion of cup anteversion from 20° differed between direct anterior approach and posterolateral or direct lateral approach (P<0.05 for each). The mean LLD was 1.3±6.6mm for direct anterior approach, 3.0±8.6mm for posterolateral approach, and 2.6±7.4mm for direct lateral approach. The mean LLD did not differ significantly among the three groups. The ratio of patients with both cup inclination of 30–50° and cup anteversion of 10–30° was significantly better for direct anterior approach than for posterolateral or direct lateral approach (78% vs. 52% and 52%, respectively; p<0.05). The ratios of femoral stem varus/valgus and LLD of 10 mm or less did not differ among the groups. Conclusions. The direct anterior approach in THA appeared to have small dispersion of cup anteversion angle and high ratio of cup component position in our target zone compared with the posterolateral and direct lateral approaches. However, the LLD and femoral stem varus/valgus after THA did not differ significantly among the three approaches postoperatively

Objective. In total hip arthroplasty (THA), the femoral component influences leg length inequality and gait, and is associated with poor muscle strength and other unsatisfactory long-term results. We have therefore used intraoperative radiographs to acquire accurate measurements of femoral component size and position. At the last meeting of this society, we reported that accurate positioning was successfully achieved in 68 cases (87.2%) as a consequence of taking intraoperative radiographs. However, we have little understanding as regards to the accuracy of X-ray measurements. We accordingly undertook an examination of the accuracy of such measurements. The purpose of this study was to evaluate the difference between leg length discrepancy (LLD) measured using X-ray and computed tomography (CT). Materials and Methods. The study group comprised 48 primary THAs performed between October 2010 and April 2012. Using 2D template software (JMM Corporation), we measured LLD using pre-operative anteroposterior (AP) radiographs of the pelvis. On the basis of both teardrop lines, we measured LLD of the lesser trochanter top (Fig. 1), lesser trochanter direct top (Fig. 2), and trochanteric top (Fig. 3). Furthermore, using Aquarius NET software, we measured LLD using AP and lateral scout views of the pelvis and bilateral femurs. This data was defined as the true LLD. The difference between the X-ray data (lesser trochanter top, lesser trochanter direct top, and trochanteric top) and the CT data was defined as accuracy. Additionally, we measured the size of the lesser trochanter and examined the association. Results. The mean LLD was 11.4, 12.1, and 9.6 mm on the lesser trochanter top, the lesser trochanter direct top, and the trochanteric top of radiographs, respectively, and 11.6 mm on CT scans. Precision was within 5 mm of the true LLD in 42 cases (87.5%) for the lesser trochanter top, 36 cases (75.0 %) for the lesser trochanter direct top, and 27 cases (63.0%) for the trochanteric top. We observed no association between the size of the lesser trochanter and the measurement accuracy. Conclusions. When using X-ray measurements, the lesser trochanter top is the most useful site for LLD measurement

Introduction: Leg length discrepancy (LLD) following total hip arthroplasty (THA) can lead to disappointed patients, increased dislocation, increased wear and suboptimal function. It is one of the commonest reasons for litigation following THA in the United States. The purpose of this study was to radiologically and functionally assess the efficacy of a simple technique for intra-operative leg length assessment during THA via a posterior approach. Materials & Methods: This technique was undertaken in 50 consecutive THAs. The pre-and 3 month postoperative LLD was measured on standing AP pelvis radiographs. The results were compared with 50 THAs performed by the same surgeons without using the technique. Pre-and post-operative OHS and UCLA scores were recorded in both groups. Results: In the control group the mean pre- and postoperative LLD was 9.38 mm and 7.75mm respectively. In the new technique group the mean pre-operative LLD was 11.37 and the post-operative LLD was 1.70mm. The final LLD was significantly less in the new technique group (p< 0.001). Fifteen patients in the control group and three patients in the new technique group had post–operative lengthening. Oxford Hip and UCLA score improvement in new technique group was greater than in the control group (p< 0.05). Discussion: The technique we introduced to assess leg length intra-operatively has shown to be safe, reliable and accurate. We have nonetheless demonstrated much greater accuracy at providing equal leg lengths and improved functional outcome using this new technique

Purpose: This study investigates the use of photodynamic therapy (PDT) in regulating bone development with a view to its potential role in treating Juvenile leg length discrepancy (LLD). Methods: Transgenic mice expressing the luciferase firefly gene upon activation of a promoter sequence specific to the vascular endothelial growth factor (VEGF) gene were subject to benzoporphyrin derivative monoacid (BPD-MA)-mediated PDT in the right, tibial epiphyseal growth plate at the age of 3 weeks. BPD-MA was administered intracardially (2mg/kg) followed 10 mins later by a laser light (690 +/− 5 nm) at a range of doses (5-27J, 50 mW output) delivered either as a single or repeat regimen (x2-3). Contra-lateral legs served as no-light controls. Further controls included animals that received light treatment in the absence of photosensitizer or no treatment. Mice were imaged for VEGF related bioluminescence (photons/sec/steradian) at t= 0, 24, 48, 72 h and 1–4 weeks post PDT. FaxitronÔ x-ray images provided accurate assessment of bone morphometry. Upon sacrifice, the tibia and femur of the treated and untreated limbs were harvested, imaged and measured again and prepared for histology. A number of animals were sacrificed at 24 h post PDT to allow immunohistochemical staining for CD31, VEGF and hypoxia-inducible factor (HIF-1 alpha) within the bone. Results: PDT-treated (10 J, x2) mice displayed enhanced bioluminescence at the treatment site (and ear nick) for up to 4 weeks post treatment while control mice were bioluminescent at the ear-nick site only. Repeat regimens provided greater shortening of the limb than the corresponding single treatment. PDT-treated limbs were shorter by 3–4 mm on average as compared to the contra lateral and light only controls (10 J, x2). Immunohistochemistry confirmed the enhanced expression VEGF and CD31 at 4 weeks post-treatment although no increase in HIF-1& #945; was evident at either 24 h or 4 weeks post PDT treatment. Conclusions: Results confirm the utility of PDT to provide localized effects on bone development that may be applicable to other related skeletal deformities

Introduction: Leg length discrepancy (LLD) following total hip replacement (THR) is not uncommon. Some patients are symptomatic, with problems such as gait imbalance or back pain. LLD is a potential cause of litigation following THR. We have observed that some patients perceive their LLD to be much greater than the true LLD. A large LLD is sometimes reported by therapists, despite only a small true LLD. We have found that abduction tightness is a potent cause of apparent LLD, and report our investigations into this phenomenon. Method: We have identified a series of patients with abductor tightness and a significant apparent LLD. The LLD becomes apparent when the operated leg is adducted to the midline (or when the patient stands with their ankles together). This causes the contralateral pelvis to elevate and the un-operated leg to “shorten”. Clinical photographs and videos have been produced to demonstrate this phenomenon. A 2-dimensional model has been made to demonstrate how the degree of abduction, offset and over-lengthening affect this phenomenon. A computer model has been used to quantify these effects. Results: An abduction contracture after THR will cause the un-operated leg to be apparently and functionally short, even in the absence of a true discrepancy. Even with only minor abductor tightness, increasing the true length will disproportionately increase the apparent LLD. In the presence of tight abductors, increasing the offset will cause apparent shortening in the contra-lateral limb. Patients are who have adequate adduction are frequently unaware of true lengthening. Conclusion: An abduction contracture is a potent cause of apparent LLD. Even a small degree of true over lengthening will be greatly magnified by this phenomenon. We recommend careful clinical assessment for abductor tightness when examining patients complaining of a LLD after THR

Background. Exeter Trauma Stem (ETS) is a polished tapered collarless monopolar prosthesis used for cemented hemiarthroplasty for fracture neck of femur. Two modular rasps are available on the instrumentation set. The larger rasp, in practice, rarely fits into the femur making trial reduction impossible. Our hypothesis was that the absence of a trial reduction could affect leg length and stability of the prosthesis. Aim. To evaluate the leg length discrepancy following use of Exeter Trauma Stem for intracapsular fracture neck of femur. Methods. All patients who underwent ETS hemiarthroplasty between June 2009 to March 2010 (n = 100) were included in the study. Radiographic assessment of leg length was performed by two independent assessors based on measurements by Woolson et al. Results. Upto half of the patients had equal leg length measurements. Forty four patients had lengthening of the operated leg with a mean of 10mm (5–25). Further complications included four dislocations. There was no statistical significance between leg lengths and dislocations. Conclusion. Care is needed with regards to correct positioning of the ETS prosthesis to achieve equal leg lengths. Following this study a new intermediate sized modular rasp has been introduced to the instrumentation set

Introduction: Although THR can provide excellent pain relief and restore functional ability for most patients, there is a proportion of patients who experience a poor functional outcome after THR. One factor that could contribute to a poor outcome after THR is leg length discrepancy (LLD). Restoration of leg length is important in optimising hip biomechanics and LLD has several consequences for the patient, including back pain and a limp. Assessment of LLD using radiographs is time consuming and labour intensive, and therefore limits large scale studies of LLD. However, patients self-report of perceived LLD may be a useful tool to study LLD on a large scale. Therefore, the aim of this postal audit survey was to determine the prevalence of patient-perceived LLD after primary THR and its impact on mid-term functional outcomes. Methods: A cross-sectional postal audit survey of all consecutive patients who had a primary, unilateral THR at the Avon Orthopaedic Centre 5–8 years previously was conducted. Several questions about LLD were included on the questionnaire. Firstly, patients were asked if they thought that their legs were the same length. For those who thought their legs were different lengths, they were asked if the difference bothered them, whether the difference in length leg was enough to comment upon, and whether they used a shoe raise. Participants also completed an Oxford hip score (OHS), which is a self-report measure that assesses functional ability and pain after THR, including limping. Results: 1,114 THR patients returned a completed questionnaire, giving a response rate of 73%. 329 patients (30%) reported that they thought their legs were different lengths. The median OHS for patients with a perceived LLD was 22, which was significantly worse than the OHS of 18 for patients who thought their legs were the same length (p< 0.001). Of the 329 patients with a perceived LLD, 161 patients (51%) were bothered by the difference, 65 patients (20%) thought the discrepancy was sufficient to comment upon and 101 patients (31%) used a shoe raise. 31% of patients with LLD limped most or all of the time compared to only 9% of patients without LLD. Conclusion: In conclusion, this study found that the prevalence of perceived LLD at 5–8 years after THR was 30%. Of the patients with LLD, over 50% were bothered by the LLD and over a third used a shoe raise to equalise leg lengths. Patients with perceived LLD have a significantly poorer self-report functional outcome than those patients without LLD. It is therefore important that patients are informed pre-operatively of the high risk of LLD after THR and the associated negative impact this may have on their outcome

Background:. Total hip arthroplasty (THA) has been proven to be successful in achieving adequate pain relief and favorable outcomes in patients suffering from hip osteoarthritis (OA). However, leg length discrepancy (LLD) is still a significant cause of morbidities such as nerve damage, low back pain and abnormal gait. Despite most of the reported values of LLD in the literature being within the acceptable threshold of < 10 mm, some patients still report dissatisfaction, leading to litigation against orthopedic surgeons. However, lower extremity lengthening is sometimes necessary to achieve adequate hip joint stability and prevent dislocations. The purpose of this study was to compare LLD in patients undergoing THA using three different techniques: conventional anterior-approach THA (ATHA), conventional posterior-approach THA (PTHA), and robotic-assisted posterior-approach THA (RTHA) using the MAKO™ robotic hip system. Materials and Methods:. All cases of RTHA, ATHA and PTHA that were performed by the senior surgeon between Sep 2008 and Dec 2012 were reviewed. Patients included in this study had a primary diagnosis of hip osteoarthritis, with available and proper post-operative antero-posterior pelvis radiographs. All radiographs were calibrated and measurements done twice by two blinded observers. Results:. After exclusions, 67 RTHA cases, 29 ATHA cases and 59 PTHA cases were included in this study. There was a strong inter- and intra-observer correlation for all LLD measurements (r > 0.9, p < 0.001 in all). Mean LLD in the RTHA, ATHA and PTHA groups was 2.7 ± 1.8 mm (CI. 95. : 2.3, 3.2), 1.8 ± 1.6 mm (CI. 95. : 1.2, 2.4) and 1.9 ± 1.6 mm (CI. 95. : 1.5, 2.4) respectively (p = 0.01). When LLD > 3 mm was set as an outlier, the percentage of patients in the RTHA, ATHA and PTHA groups was 37.3%, 17.2% and 22% respectively (p value range, 0.06–0.78). When LLD > 5 mm was set as an outlier, the percentage of patients in the RTHA, ATHA and PTHA groups was 10.4%, 6.9% and 8.5% respectively (p value range, 0.72–1.0). None of the patients in all three groups had LLD ≥ 10 mm (Figure 1). Conclusion:. The results of the current study demonstrate the accuracy of the MAKO™ system in obtaining minimal LLD compared to the conventional anterior-approach and conventional posterior-approach THA, with no cases having LLD > 10 mm

Introduction: The goal of surgical equalization of leg length discrepancy (LLD) is to improve the quality of life (QOL) of affected individuals by improving function and appearance. While many surgeons utilize a cut off point of 2cm as a treatment guide, little attention has been focused on the effect of LLD on QOL. The purpose is to determine the critical cut off size for the effect of LLD on QOL. Such information may help refine the surgical indications of leg length equalization in these patients. Methods: QOL and scanogram data were collected from children diagnosed with LLD at our institution. QOL was assessed using the parent short-form of the Child Health Questionnaire (CHQ). QOL scores from this group were compared to normative data. Correlation analyses and independent t-tests were conducted to assess the relationship between size of LLD and QOL. Results: Our cohort consists of 41 patients (50 observations) with an average LLD of 2.05cm. Compared to norms, LLD patients scored significantly lower on four CHQ domains. Correlation analyses revealed a negative relationship between size of LLD and several psychosocial domains. Independent t-test revealed that children with LLD greater than or equal to 2cm scored significantly (p< 0.05) higher in six domains than children with LLD> 2cm: General Health, Parental Impact-Emotional Scale, Parental Impact-Time Scale, Family Activities, Family Cohesion, Psychosocial Summary Score. Discussion and conclusion: With increasing LLD, differences in psychosocial health become especially apparent. This study suggests that children with LLD> 2 cm experience perturbations in QOL, supporting the use of this cut off as a guideline for intervention

We reviewed and radiographed 30 skeletally-mature patients after isolated closed femoral shaft fractures in childhood which had been treated conservatively. When the fracture had occurred between the ages of 7 and 13 years, the limb overgrew about 1 cm regardless of sex, upper limb dominance, age, fracture site or configuration. Excessive fracture overlap at the time of injury, but not at union, increased limb overgrowth. Angulation of the fracture remodelled in children injured under 10 years of age, but in older patients this sometimes added to limb shortening. Rotational deformities were minor and gave no symptoms. Treatment of the 7- to 13-year-old patient should aim at 1 cm overlap at union, with correction of angular deformity being more important in children over 10 years of age. This management of fractures will give a maximum leg length discrepancy of 1 cm at skeletal maturity

Purpose and Background. Leg length discrepancy (LLD) occurs commonly and has been associated with osteoarthritis of the knee and the hip joints. However, the possible association between LLD and degenerative changes in the lumbar spine has not been investigated. Here we correlate the degree of LLD with degenerative changes in the hip joints and the lumbar spine. Methods and Results. A modification of Friberg's method was used to measure LLD and a novel method was devised to exclude magnification errors in standing radiographs of the lumbopelvic region. 5mm of LLD was considered significant. 75 sets (36 female and 39 male) of radiographs from adult patients presenting to chiropractic teaching clinics were used. Degenerative changes at hip and L4/5 and L5/S1 disc spaces were graded on a 4-point scale. Hip degeneration in men with significant LLD was [mean, 95% confidence interval] [1.35, 1.05–1.66], as opposed to men with no significant LLD [0.31, 0.1–0.53]. Degenerative changes at the L5/S1 spinal level in the group with significant LLD demonstrated values of [1.04, 0.75–1.33], compared to the group without significant LLD with values of [0.41, 0.22–0.61]. The association between LLD and lumbar degeneration was particularly strong in men and also in women at or above the age of 25. Conclusion. Here we demonstrate that LLD of 5mm or above, as measured by our method, is associated with significant degenerative changes in the hip joint in men and the L5/S1 motion segment in both men and women, but may be more significant in older women. This abstract has not been previously published in whole or substantial part nor has it been presented previously at a national meeting

Acetabular cup positioning remains a real challenge and component malpositioning after total hip arthroplasty (THA) can lead to increased rates of dislocation and wear. It is a common cause for revision THA. A novel 3D imageless mini-optical navigation system was used during THA to provide accurate, intraoperative, real-time, and non-fluoroscopic data including component positioning to the surgeon. This retrospective comparative single surgeon and single approach study examined acetabular component positioning between traditional mini-posterolateral THA and mini-posterolateral THA using the 3D mini-optical navigation system. A retrospective chart review was conducted of 157 consecutive (78 3D mini-optical navigation and 79 traditional non-navigation methods) THAs performed by the senior author using a mini-posterolateral approach at an ambulatory surgery center and hospital setting. Two independent reviewers analyzed postoperative radiographs in a standardized fashion to measure acetabular component positioning. Demographic, clinical, surgical, and radiographic data were analyzed.

These groups were found to have no statistical difference in age, gender, and BMI (Table I). There was no difference between groups in acetabular components in the Lewinnek safe zone, 31.2% vs 26.6% (p = 0.53). Cup anteversion within the safe zone did not differ, 35.1% vs 40.5% (p = 0.48); while cup inclination within the safe zone differed, with more in the navigation group, 77.9% vs 51.9% (p < 0.01). Change in leg length was significantly different with the navigation group's leg length at 1.9 ± 6.3, less than the traditional at 5.4 ± 7.0 (p < 0.01). There was no difference in mean change in offset between groups (4.5 ± 5.9 vs 6.2 ± 7.9, p = 0.12); navigation, traditional) (Table II). The 3D mini-optical navigation group did have significantly longer operative time (98.4 ± 17.5 vs 89.3 ± 15.5 p < 0.01). Use of the novel 3D Mini-optical Navigation System significantly improved cup inclination compared to traditional methods while increasing operative time.

For any figures or tables, please contact the authors directly.

Aims

Leg length inequality following total hip replacement remains common. In an effort to reduce this occurrence, surgeons undertake pre-operative templating and use various forms of intra-operative measurements, including computer navigation. This study aims to delineate which measurement technique is most appropriate for measuring leg length inequality from a pelvic radiograph.

The August 2024 Hip & Pelvis Roundup. 360. looks at: Understanding perceived leg length discrepancy post-total hip arthroplasty: the role of pelvic obliquity; Influence of femoral stem design on revision rates in total hip arthroplasty; Outcomes of arthroscopic labral treatment of femoroacetabular impingement in adolescents; Characteristics and quality of online searches for direct anterior versus posterior approach for total hip arthroplasty; Rapid return to braking after anterior and posterior approach total hip arthroplasty; How much protection does a collar provide?; Timing matters: reducing infection risk in total hip arthroplasty with corticosteroid injection intervals; Identifying pain recovery patterns in total hip arthroplasty using PROMIS data

Aims. The purpose of this study was to compare the clinical, radiological, and patient-reported outcome measures (PROMs) in the first 100 consecutive patients undergoing total hip arthroplasty (THA) via a direct superior approach (DSA) with a matched group of patients undergoing THA by the same surgeon, using a posterolateral approach (PLA). Methods. This was a retrospective single surgeon study comparing the first 100 consecutive DSA THA patients with a matched group of patients using a standard PLA. Case notes were examined for patient demographics, length of hospital stay, operating time, intra- and postoperative complications, pain score, satisfaction score, and Oxford Hip Score (OHS). Leg length discrepancy and component positioning were measured from postoperative plain radiographs. Results. The DSA patients had a shorter length of hospital stay (mean 2.09 days (SD 1.20) DSA vs 2.74 days (SD 1.17) PLA; p < 0.001) and shorter time to discharge from the inpatient physiotherapy teams (mean 1.44 days (SD 1.17) DSA vs 1.93 days (SD 0.96) PLA; p < 0.001). There were no differences in operating time (p = 0.505), pain levels up to postoperative day 1 (p = 0.106 to p =0.242), OHS (p = 0.594 to p = 0.815), satisfaction levels (p = 0.066 to p = 0.299), stem alignment (p = 0.240), acetabular component inclination (p < 0.001) and anteversion (p < 0.001), or leg length discrepancy (p = 0.134). Conclusion. While the DSA appears safe and was not associated with a significant difference in PROMs, radiological findings, or intraoperative or postoperative complications, a randomized controlled trial with functional outcomes in the postoperative phase is needed to evaluate this surgical approach formally. Cite this article: Bone Joint J 2021;103-B(3):500–506

Aims. To develop a core outcome set of measurements from postoperative radiographs that can be used to assess technical skill in performing dynamic hip screw (DHS) and hemiarthroplasty, and to validate these against Van der Vleuten’s criteria for effective assessment. Methods. A Delphi exercise was undertaken at a regional major trauma centre to identify candidate measurement items. The feasibility of taking these measurements was tested by two of the authors (HKJ, GTRP). Validity and reliability were examined using the radiographs of operations performed by orthopaedic resident participants (n = 28) of a multicentre randomized controlled educational trial (ISRCTN20431944). Trainees were divided into novice and intermediate groups, defined as having performed < ten or ≥ ten cases each for DHS and hemiarthroplasty at baseline. The procedure-based assessment (PBA) global rating score was assumed as the gold standard assessment for the purposes of concurrent validity. Intra- and inter-rater reliability testing were performed on a random subset of 25 cases. Results. In total, 327 DHS and 248 hemiarthroplasty procedures were performed by 28 postgraduate year (PGY) 3 to 5 orthopaedic trainees during the 2014 to 2015 surgical training year at nine NHS hospitals in the West Midlands, UK. Overall, 109 PBAs were completed for DHS and 80 for hemiarthroplasty. Expert consensus identified four ‘final product analysis’ (FPA) radiological parameters of technical success for DHS: tip-apex distance (TAD); lag screw position in the femoral head; flushness of the plate against the lateral femoral cortex; and eight-cortex hold of the plate screws. Three parameters were identified for hemiarthroplasty: leg length discrepancy; femoral stem alignment; and femoral offset. Face validity, content validity, and feasibility were excellent. For all measurements, performance was better in the intermediate compared with the novice group, and this was statistically significant for TAD (p < 0.001) and femoral stem alignment (p = 0.023). Concurrent validity was poor when measured against global PBA score. This may be explained by the fact that they are measuring difference facets of competence. Intra-and inter-rater reliability were excellent for TAD, moderate for lag screw position (DHS), and moderate for leg length discrepancy (hemiarthroplasty). Use of a large multicentre dataset suggests good generalizability of the results to other settings. Assessment using FPA was time- and cost-effective compared with PBA. Conclusion. Final product analysis using post-implantation radiographs to measure technical skill in hip fracture surgery is feasible, valid, reliable, and cost-effective. It can complement traditional workplace-based assessment for measuring performance in the real-world operating room . It may have particular utility in competency-based training frameworks and for assessing skill transfer from the simulated to live operating theatre. Cite this article: Bone Joint Open 2020;1-9:594–604

Introduction. Leg length discrepancy (LLD) is a common sequalae of limb reconstruction procedures. The subsequent biomechanical compensation can be directly linked to degenerative arthritis, lower back pain, scoliosis and functional impairment. It becomes particularly problematic when >2cm, established as a clinical standard. This two-arm experimental study assesses how reliable an iPhone application is in the measurement of LLD at different distances in control and LLD patients. Materials and Methods. 42 participants were included in the study, divided evenly into 21 control and 21 LLD patients. A standardised measurement technique was used to obtain TMM and iPhone application measurements, taken at a distance of 0.25m, 0.50m and 0.75m. Results. The mean discrepancy of iPhone-based measurements in the control group was 1.57cm, 1.59cm and 2.19cm at 0.25m, 0.50m and 0.75m respectively. This compares to measurements in the LLD cohort with a mean discrepancy of 1.71cm, 1.85cm and 2.19cm. The overall mean discrepancy of iPhone data was 1.78cm in the control cohort compared to 1.92cm in the LLD cohort. Conclusions. Results suggest that the iPhone application can be used to identify clinically significant leg length discrepancies. At 0.75 metres anomalous results become more prevalent and the accuracy of the application appears to decline. The results also suggest the application is slightly more accurate in the control group, nevertheless, in distances up to 0.50 metres the mean discrepancy sits within the 2cm standard of clinically significant LLD

Aims. The aim of this study was to assess the safety and clinical outcome of patients with a femoral shaft fracture and a previous complex post-traumatic femoral malunion who were treated with a clamshell osteotomy and fixation with an intramedullary nail (IMN). Methods. The study involved a retrospective analysis of 23 patients. All had a previous, operatively managed, femoral shaft fracture with malunion due to hardware failure. They were treated with a clamshell osteotomy between May 2015 and March 2020. The mean age was 42.6 years (26 to 62) and 15 (65.2%) were male. The mean follow-up was 2.3 years (1 to 5). Details from their medical records were analyzed. Clinical outcomes were assessed using the quality of correction of the deformity, functional recovery, the healing time of the fracture, and complications. Results. The mean length of time between the initial injury and surgery was 4.5 years (3 to 10). The mean operating time was 2.8 hours (2.05 to 4.4)), and the mean blood loss was 850 ml (650 to 1,020). Complications occurred in five patients (21.7%): two with wound necrosis, and three with deep vein thrombosis. The mean coronal deformity was significantly corrected from 17.78° (SD 4.62°) preoperatively to 1.35° (SD 1.72°) postoperatively (p < 0.001), and the mean sagittal deformity was significantly corrected from 20.65° (SD 5.88°) preoperatively to 1.61° (SD 1.95°; p < 0.001) postoperatively. The mean leg length discrepancy was significantly corrected from 3.57 cm (SD 1.27) preoperatively to 1.13 cm (SD 0.76) postoperatively (p < 0.001). All fractures healed at a mean of seven months (4 to 12) postoperatively. The mean Lower Extremity Functional Scale score improved significantly from 45.4 (SD 9.1) preoperatively to 66.2 (SD 5.5) postoperatively (p < 0.001). Partial cortical nonunion in the deformed segment occurred in eight patients (34.8%) and healed at a mean of 2.4 years (2 to 3) postoperatively. Conclusion. A clamshell osteotomy combined with IMN fixation in the treatment of patients with a femoral shaft fracture and a previous post-traumatic femoral malunion achieved excellent outcomes. Partial cortical nonunions in the deformed segment also healed satisfactorily. Cite this article: Bone Joint J 2023;105-B(4):449–454

Aims. Temporary epiphysiodesis (ED) is commonly applied in children and adolescents to treat leg length discrepancies (LLDs) and tall stature. Traditional Blount staples or modern two-hole plates are used in clinical practice. However, they require accurate planning, precise surgical techniques, and attentive follow-up to achieve the desired outcome without complications. This study reports the results of ED using a novel rigid staple (RigidTack) incorporating safety, as well as technical and procedural success according to the idea, development, evaluation, assessment, long-term (IDEAL) study framework. Methods. A cohort of 56 patients, including 45 unilateral EDs for LLD and 11 bilateral EDs for tall stature, were prospectively analyzed. ED was performed with 222 rigid staples with a mean follow-up of 24.4 months (8 to 49). Patients with a predicted LLD of ≥ 2 cm at skeletal maturity were included. Mean age at surgery was 12.1 years (8 to 14). Correction and complication rates including implant-associated problems, and secondary deformities as well as perioperative parameters, were recorded (IDEAL stage 2a). These results were compared to historical cohorts treated for correction of LLD with two-hole plates or Blount staples. Results. The mean LLD was reduced from 25.2 mm (15 to 45) before surgery to 9.3 mm (6 to 25) at skeletal maturity. Implant-associated complications occurred in 4/56 treatments (7%), and secondary frontal plane deformities were detected in 5/45 legs (11%) of the LLD cohort. Including tall stature patients, the rate increased to 12/67 legs (18%). Sagittal plane deformities were observed during 1/45 LLD treatments (2%). Compared to two-hole plates and Blount staples, similar correction rates were observed in all devices. Lower rates of frontal and sagittal plane deformities were observed using rigid staples. Conclusion. Treatment of LLD using novel rigid staples appears a feasible and promising strategy. Secondary frontal and sagittal plane deformities remain a potential complication, although the rate seems to be lower in patients treated with rigid staples. Further comparative studies are needed to investigate this issue. Cite this article: Bone Joint J 2021;103-B(8):1428–1437

Aims. Traditionally, acetabular component insertion during total hip arthroplasty (THA) is visually assisted in the posterior approach and fluoroscopically assisted in the anterior approach. The present study examined the accuracy of a new surgeon during anterior (NSA) and posterior (NSP) THA using robotic arm-assisted technology compared to two experienced surgeons using traditional methods. Methods. Prospectively collected data was reviewed for 120 patients at two institutions. Data were collected on the first 30 anterior approach and the first 30 posterior approach surgeries performed by a newly graduated arthroplasty surgeon (all using robotic arm-assisted technology) and was compared to standard THA by an experienced anterior (SSA) and posterior surgeon (SSP). Acetabular component inclination, version, and leg length were calculated postoperatively and differences calculated based on postoperative film measurement. Results. Demographic data were similar between groups with the exception of BMI being lower in the NSA group (27.98 vs 25.2; p = 0.005). Operating time and total time in operating room (TTOR) was lower in the SSA (p < 0.001) and TTOR was higher in the NSP group (p = 0.014). Planned versus postoperative leg length discrepancy were similar among both anterior and posterior surgeries (p > 0.104). Planned versus postoperative abduction and anteversion were similar among the NSA and SSA (p > 0.425), whereas planned versus postoperative abduction and anteversion were lower in the NSP (p < 0.001). Outliers > 10 mm from planned leg length were present in one case of the SSP and NSP, with none in the anterior groups. There were no outliers > 10° in anterior or posterior for abduction in all surgeons. The SSP had six outliers > 10° in anteversion while the NSP had none (p = 0.004); the SSA had no outliers for anteversion while the NSA had one (p = 0.500). Conclusion. Robotic arm-assisted technology allowed a newly trained surgeon to produce similarly accurate results and outcomes as experienced surgeons in anterior and posterior hip arthroplasty. Cite this article: Bone Jt Open 2021;2(6):365–370

Aims. Improvements in functional results and long-term survival are variable following conversion of hip fusion to total hip arthroplasty (THA) and complications are high. The aim of the study was to analyze the clinical and functional results in patients who underwent conversion of hip fusion to THA using a consistent technique and uncemented implants. Methods. A total of 39 hip fusion conversions to THA were undertaken in 38 patients by a single surgeon employing a consistent surgical technique and uncemented implants. Parameters assessed included Harris Hip Score (HHS) for function, range of motion (ROM), leg length discrepancy (LLD), satisfaction, and use of walking aid. Radiographs were reviewed for loosening, subsidence, and heterotopic ossification (HO). Postoperative complications and implant survival were assessed. Results. At mean 12.2 years (2 to 24) follow-up, HHS improved from mean 34.2 (20.8 to 60.5) to 75 (53.6 to 94.0; p < 0.001). Mean postoperative ROM was flexion 77° (50° to 95°), abduction 30° (10° to 40°), adduction 20° (5° to 25°), internal rotation 18° (2° to 30°), and external rotation 17° (5° to 30°). LLD improved from mean -3.36 cm (0 to 8) to postoperative mean -1.14 cm (0 to 4; p < 0.001). Postoperatively, 26 patients (68.4%) required the use of a walking aid. Complications included one (2.5%) dislocation, two (5.1%) partial sciatic nerve injuries, one (2.5%) deep periprosthetic joint infection, two instances of (5.1%) acetabular component aseptic loosening, two (5.1%) periprosthetic fractures, and ten instances of HO (40%), of which three (7.7%) were functionally limiting and required excision. Kaplan-Meier Survival was 97.1% (95% confidence interval (CI) 91.4% to 100%) at ten years and 88.2% (95% CI 70.96 to 100) at 15 years with implant revision for aseptic loosening as endpoint and 81.7% (95% CI 70.9% to 98.0%) at ten years and 74.2% (95% CI 55.6 to 92.8) at 15 years follow-up with implant revision for all cause failure as endpoint. Conclusion. The use of an optimal and consistent surgical technique and cementless implants can result in significant functional improvement, low complication rates, long-term implant survival, and high patient satisfaction following conversion of hip fusion to THA. The possibility of requiring a walking aid should be discussed with the patient before surgery. Cite this article: Bone Joint J 2021;103-B(7 Supple B):129–134

Introduction. Reconstruction of large defect of tibia following infection is considered as one of the most difficult problem facing the orthopaedic surgeon. Amputation with modern prosthetic fitting is a salvage procedure to treat big defects, which gives a functional result with unpredictable psychological impact. Materials & Methods. Between January 2000 and January 2021, 56 patients (30 males and 26 females) with big defects following infection and post traumatic injury of the tibia were treated. The mean age of the patients at the time of surgery was 20.5 years (4–24 years). The fibula was mobilized medially to fill the defect and was fixed with Ilizarov fixator. The average size of the defects reconstructed was 18.5 cm (17–20 cm). Results. The average time for complete union was 8.6 months (range, 5–9 months). At final follow-up all patients had fully united. We found leg length discrepancy in 52 patients and that was corrected by re-lengthening of the solid new regenerate bone. Conclusions. The Ilizarov method has been shown to be an effective method of treating Tibialization of fibula for reconstruction of big tibial defects