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

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

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: 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

Aims. The direct anterior approach (DAA) for total hip arthroplasty (THA) has potential advantages over other approaches and is most commonly performed with the patient in the supine position. We describe a technique for DAA THA with the patient in the lateral decubitus position and report the early clinical and radiological outcomes, the characteristics of the learning curve, and perioperative complications. Methods. All primary DAA THAs performed in the lateral position by a single surgeon over a four-year period from the surgeon’s first case using the technique were identified from a prospectively collected database. Modified Harris Hip Scores (mHHS) were collected to assess clinical outcome, and routine radiological analysis was performed. Retrospective review of the medical records identified perioperative complications, the characteristics of the learning curve, and revisions. Results. A total of 257 patients were included in the study. Their mean age was 60 years (SD 9.0). A total of 164 (64%) were female. The mean mHHS improved significantly from 52.1 (SD 16.2) preoperatively to 94.4 (SD 11) at a follow-up of one year (p < 0.001), with 212 of 225 patients (94%) achieving a minimal clinically important difference (MCID) (> 8 points). Radiological evaluation showed a mean leg length discrepancy of 2.6 mm (SD 5.9) and a mean difference in femoral offset of 0.2 mm (SD 4.9). A total of 234/243 acetabular components (96.3%) were positioned within Lewinnek’s safe zone. Analysis of operating time, blood loss, the position of the components, and complications did not identify a learning curve. A total of 14 patients (5.4%) had a major perioperative complication and three (1.2%) required revision THA. There were no major neurovascular complications and no dislocations. Conclusion. We have described and analyzed a surgical technique for undertaking DAA THA in the familiar lateral decubitus position using a routine operating table, positioning devices, and instrumentation, and shown that it can be performed safely and effectively under these circumstances. Cite this article: Bone Joint J 2021;103-B(7 Supple B):53–58

Dislocation is one of the most common complications in total hip arthroplasty (THA) and is primarily driven by bony or prosthetic impingement. The aim of this study was two-fold. First, to develop a simulation that incorporates the functional position of the femur and pelvis and instantaneously determines range of motion (ROM) limits. Second, to assess the number of patients for whom their functional bony alignment escalates impingement risk. 468 patients underwent a preoperative THA planning protocol that included functional x-rays and a lower limb CT scan. The CT scan was segmented and landmarked, and the x-rays were measured for pelvic tilt, femoral rotation, and preoperative leg length discrepancy (LLD). All patients received 3D templating with the same implant combination (Depuy; Corail/Pinnacle). Implants were positioned according to standardised criteria. Each patient was simulated in a novel ROM simulation that instantaneously calculates bony and prosthetic impingement limits in functional movements. Simulated motions included flexion and standing-external rotation (ER). Each patient's ROM was simulated with their bones oriented in both functional and neutral positions. 13% patients suffered a ROM impingement for functional but not neutral extension-ER. As a result, 48% patients who failed the functional-ER simulation would not be detected without consideration of the functional bony alignment. 16% patients suffered a ROM impingement for functional but not neutral flexion. As a result, 65% patients who failed the flexion simulation would not be detected without consideration of the functional bony alignment. We have developed a ROM simulation for use with preoperative planning for THA surgery that can solve bony and prosthetic impingement limits instantaneously. The advantage of our ROM simulation over previous simulations is instantaneous impingement detection, not requiring implant geometries to be analysed prior to use, and addressing the functional position of both the femur and pelvis

Cannulated hip screws are frequently used in the management of hip fractures. There have been concerns over the failure rate of the technique and the outcomes of those that subsequently require conversion to total hip replacement (THR). This study utilised a database of over 600 cannulated hip screw (CHS) fixations performed over a 14-year period and followed up for a minimum of one year (1-14). We identified 57 cases where a conversion to THR took place (40 females, 17 males, mean age: 71.2 years). Patient demographics, original mechanism of injury, fracture classification, reason for fixation failure, time until arthroplasty, implant type and post-arthroplasty complications were recorded. Clinical outcomes were measured using the Oxford Hip Score. The failure rate of cannulated screw treatment was 9.4% and the mean time from initial fixation to arthroplasty was 15.4 (16.5) months. Thirty six fractures were initially undisplaced and 21 were displaced. As one might expect the displaced cases tended to be younger but this didn't reach statistical significance [66.5(14.3) vs 72.7(13.1), p=0.1]. The commonest causes of failure were non-union (25 cases, 44%) and avascular necrosis (17 cases, 30%). Complications after THR consisted of one leg length discrepancy and one peri-prosthetic fracture. The mean Oxford score pre-arthroplasty was 12.2 (8.4), improving to 38.4 (11.1) at one-year. Although the pre op Oxford scores tended to be lower in patients with undisplaced fractures and higher ASA scores, the improvement was the same whatever the pre-op situation. The one-year Oxford score and the improvement in score are comparable to those seen in the literature for THR in general. In conclusion, CHS has a high success rate and where salvage arthroplasty is required it can provide good clinical outcomes with low complication rates

Introduction. The use of vascularised fibula grafts is an accepted method for reconstructing the distal femur following resection of malignant childhood tumours. Limitations relate to the mismatch of the cross-sectional area of the transplanted fibula graft and thel ocal bone, instability of the construct and union difficulties. We present midterm results of a unique staged technique—an immediate defect reconstruction using a double-barrel vascularised fibula graft set in in A-frame configuration and a subsequent intramedullary femoral lengthening. Materials & Methods. We retrospectively included 10 patients (mean age 10 y)with an osteosarcoma of the distal femur, who were treated ac-cording to the above-mentioned surgical technique. All patients were evaluated with regards to consolidation of the transplanted grafts, hypertrophy at the graft-host junctions, leg length discrepancies, lengthening indices, complications as well as functional outcome. Results. The mean defect size after tumour resection was 14.5 cm, the mean length of the harvested fibula graft 22 cm, resulting in a mean (acute) shortening of 4.7 cm (in 8 patients). Consolidation was achieved in all cases, 4 patients required supplementary bone grafting. Hypertrophy at the graft-host junctions was observed in78% of the evaluable junctions. In total 11 intramedullary lengthening procedures in 9 patients had been performed at the last follow up. The mean Muskuloskeletal Society Rating Scale(MSTS) score of the evaluable 9 patients was 85% (57% to 100%)with good or excellent results in 7 patients. Conclusions. A-frame vascularised fibula reconstructions showed encouraging results with respect to defect reconstruction, length as well as function and should therefore be considered a valuable option for reconstruction of the distal femur after osteosarcoma resection. The surgical implementation is demanding though, which is emphasized by the considerable high number of com-plications requiring surgical intervention, even though most were not serious

Background. Total ankle replacements (TARs) are becoming increasingly more common in the treatment of end stage ankle arthritis. As a consequence, more patients are presenting with the complex situation of the failing TAR. The aim of this study was to present our case series of isolated ankle fusions post failed TAR using a spinal cage construct and anterior plating technique. Methods. A retrospective review of prospectively collected data was performed for 6 patients that had isolated ankle fusions performed for failed TAR. These were performed by a single surgeon (IW) between March 2012 and October 2014. The procedure was performed using a Spinal Cage construct and grafting in the joint defect and anterior plating. Our primary outcome measure was clinical and radiographic union at 1 year. Union was defined as clinical union and no evidence of radiographic hardware loosening or persistent joint lucent line at 1 year. Results. The mean follow-up was 37.3 months (SD 13.2). Union was achieved in 5 of the 6 patients (83%). One patient had a non-union that required revision fusion incorporating the talonavicular joint that successfully went on to unite across both joints. Another patient had radiographic features of non-union but was clinically united and asymptomatic and one required revision surgery for a bulky symptomatic lateral malleolus with fused ankle joint. Conclusion. The failing TAR presents a complex clinical situation. After removal of the implant there is often a large defect which if compressed leads to a leg length discrepancy and if filled with augment can increase the risk of non-union. Multiple methods have been described for revision, with many advocating fusion of both the ankle joint and subtalar joint. We present our case series using a spinal cage and anterior plating that allows preservation of the subtalar joint and a high rate of union

Introduction. Coronal malalignment and leg length discrepancies (LLD) are frequently associated. Temporary hemiepiphysiodesis (tHED) is commonly employed for the correction of limb malalignment in skeletally immature patients. For treatment of LLD greater than 2 cm, lengthening with intramedullary legnthening nails is a safe and reliable technique. However, the combined application of these approaches in skeletally immature patients has not yet been investigated. Materials & Methods. Retrospective radiological and clinical analysis of 25 patients (14 females, 11 males) who underwent intramedullary femoral lengthening with an antegrade PRECICE® lengthening nail as well as tHED of the distal femur and / or proximal tibia between 2014 and 2019. tHED was conducted by implantation of flexible staples (FlexTack™) either prior (n = 11), simultaneously (n = 10), or subsequently (n = 4) to femoral lengthening. The mean follow-up period was 3.7 years (±1.4). Results. The median initial LLD was 39.0 mm (35.0–45.0). 21 patients (84%) presented valgus and 4 (16%) showed varus malalignment. Leg length equalization was achieved in 13 patients at skeletal maturity (62%). The median LLD of patients with a residual LLD > 10 mm was 15.5 mm (12.8–21.8). Limb realignment was obtained in nine of seventeen skeletally mature patients (53%) in the valgus group, and in one of four patients (25%) in the varus group. Conclusions. The combination of antegrade femoral lengthening and tHED can efficiently correct LLD and coronal limb malalignment in skeletally immature patients. Nevertheless, achieving limb length equalization and realignment may render difficult in cases of severe LLD and angular deformity. Furthermore, the reported techniques ought to be thoroughly planned and executed and require regular clinical and radiological examinations until skeletal maturity to avoid - or timely detect and manage - adverse events such as overcorrection and rebound of deformity

Subsidence remains a concern when utilizing modern tapered fluted titanium (TFT) femoral stems and may lead to leg length discrepancy, impingement, instability and failure to obtain stem osseointegration. This study aims to compare stem subsidence across three modern TFT stems. Our secondary aim was to investigate the influence of bicortical contact or ‘scratch fit’ on subsidence, as well as the role of intraoperative imaging in maximizing this bicortical contact and preventing stem subsidence. A retrospective review of 271 hip arthroplasties utilizing modern TFT stems in a single institution was performed. Three stem designs were included in the analysis: one monoblock TFT stem (n=91) and two modular TFT stems (Modular A [n=90]; Modular B [n=90]). Patient demographics, Paprosky femoral bone loss classification, bi-cortical contact, utilization of intra-operative imaging and stem subsidence (comparison of initial post-operative radiograph to the latest follow up radiograph - minimum three months) were recorded. There was no statistically significant difference in the amount of subsidence between the three stems (Monoblock: 2.33mm, Modular A: 3.43mm, Modular B: 3.02mm; p=0.191). There was no statistical difference in subsidence >5mm between stems (Monoblock: 9.9%, Modular A: 22.2%, Modular B: 16.7%). Subgroup analysis based on femoral bone loss grading showed no difference in subsidence between stems. Increased bicortical contact was strongly associated with reduced subsidence (p=0.004). Intra-operative imaging was used in 46.5% (126/271) of cases; this was not correlated with bicortical contact (p=0.673) or subsidence (p=0.521). Across all groups, only two stems were revised for subsidence (0.7%). All three modern TFT stems were highly successful and associated with low rates of subsidence, regardless of modular or monoblock design. Surgeons should select the stem that they feel is most clinically appropriate

Introduction. Femoral-shortening osteotomy for the treatment of leg length discrepancy is demanding technique. Many surgical technique and orthopaedic devises have been suggested to perform this procedure. Herein, we describe modified femoral shortening osteotomy over a nail, using a percutaneous multiple drill-hole osteotomy technique. Materials and Methods. We operated on six patients with LLD. Mean femoral shortening was 4.2 cm. Osteotomy was performed using a multiple drill-hole technique, and bone was stabilized using an intramedullary nail. Post-operative clinical and radiological data were reported. Results. Shortening was achieved, with a final LLD of < 1 cm in all patients. All patients considered the lengths of the lower limbs to be equal. No special surgical skills or instrumentation were needed. Intraoperative and post-operative complications were not recorded. Conclusions. Percutaneous femoral-shortening osteotomy over a nail using multiple drill-hole osteotomy technique was effective and safe in treating LLD

Introduction. At Sheffield Children's Hospital, treatment of leg length discrepancy is a common procedure. Historically, this has been done with external fixators. With the development in intramedullary technology, internal nails have become the preferred modality for long bone lengthening in the adolescent population. However, it is important to review whether this technology practically reduces the known challenges seen and if it brings any new issues. Therefore, the aim of this review is to retrospectively evaluate the therapeutic challenges of 16 fit-bone intramedullary femoral lengthening's at Sheffield Children's Hospital between 2021–2022. Materials & Methods. The international classification of function (ICF) framework was used to differentiate outcomes. The patient's therapy notes were retrospectively reviewed for themes around structural, activity and participation limitation. The findings were grouped for analysis and the main themes presented. Results. There were 8 males, mean age 17.4 years (range 17–18) and 8 females, mean age 15.9 years (range 14–18). 5 right and 11 left femurs were lengthened. Underlying pathology varied amongst the 16 patients. All patients went into a hinged knee brace post operatively. Structural limitations included: pain, fixed flexion deformity of the knee, loss of knee flexion, quadriceps muscle lag, muscle spasms and gluteal weakness. The primary activity limitation was reduced weight bearing with altered gait pattern. Participation limitations included reduced school attendance and involvement in activities with peers. Access to Physiotherapy from local services varied dramatically. Five of the cohort have completed treatment. Conclusions. Anecdotally, intramedullary femoral lengthening nails have perceived benefits for families compared to external fixators in the adolescent population. However, there remain musculoskeletal and psychosocial outcomes requiring therapeutic management throughout the lengthening process and beyond. Therefore, quantifying these outcomes is essential for measuring the impact on each patient for comparison. To interpret these themes, we need to evaluate the outcomes objectively, this was not done consistently in this review. Future research should look at outcome measures that are sensitive to all aspects of the ICF. With an aim of improving the therapeutic treatment provided and the overall outcome for the children treated

Pelvic bone defect in patients with severe congenital dysplasia of the hip (CDH) lead to abnormalities in lumbar spine and lower limb alignment that can determine total hip arthroplasty (THA) patients' outcome. These variables may be different in uni- or bilateral CDH. We compared the clinical outcome and the spinopelvic and lower limb radiological changes over time in patients undergoing THA due to uni- or bilateral CHD at a minimum follow-up of five years. Sixty-four patients (77 hips) undergoing THA due to severe CDH between 2006 and 2015 were analyzed: Group 1 consisted of 51 patients with unilateral CDH, and group 2, 113 patients (26 hips) with bilateral CDH. There were 32 females in group 1 and 18 in group 2 (p=0.6). The mean age was 41.6 years in group 1 and 53.6 in group 2 (p<0.001). We compared the hip, spine and knee clinical outcomes. The radiological analysis included the postoperative hip reconstruction, and the evolution of the coronal and sagittal spinopelvic parameters assessing the pelvic obliquity (PO) and the sacro-femoro-pubic (SFP) angles, and the knee mechanical axis evaluating the tibio-femoral angle (TFA). At latest follow-up, the mean Harris Hip Score was 88.6 in group 1 and 90.7 in group 2 (p=0.025). Postoperative leg length discrepancy of more than 5 mm was more frequent in group 1 (p=0.028). Postoperative lumbar back pain was reported in 23.4% of the cases and knee pain in 20.8%, however, there were no differences between groups. One supracondylar femoral osteotomy and one total knee arthroplasty were required. The radiological reconstruction of the hip was similar in both groups. The PO angle improved more in group 1 (p=0.01) from the preoperative to 6-weeks postoperative and was constant at 5 years. The SFP angle improved in both groups but there were no differences between groups (p=0.5). 30 patients in group 1 showed a TFA less than 10º and 17 in group 2 (p=0.7). Although the clinical outcome was better in terms of hip function in patients with bilateral CDH than those with unilateral CDH, the improvement in low back and knee pain was similar. Patients with unilateral dysplasia showed a better correction of the PO after THA. All spinopelvic and knee alignment parameters were corrected and maintained over time in most cases five years after THA

Introduction. While research has been carried out widely for sagital pelvic tilt, research reports for coronal pelvic obliquity are few. The aim of this study is to evaluate changes of the pelvic obliquity before and after total hip arthroplasty. Material and Methods. This retrospective study includes 146 cases of hips that were received total hip arthroplasty. There were 20 cases of revision, and 2 cases of re-revision. 17 cases were received bilateral total hip arthroplasty. The standing plain X-ray was used for evaluation of the pelvic obliquity in both before and 1-year after surgery. The correlation of pelvic obliquity was assessed between before and after surgery. 146 cases were classified into 3 groups (A, B, and C) according to the severity of the pelvic obliquity (0º−3º, 3º−6º, and >6º). Among the groups, statistical analysis was evaluated in the leg length discrepancy and the range of motion of the hip (flexion, extension, abduction, adduction, internal and external rotation) before and after surgery with 95% confidence intervals. Results. The mean pelvic obliquity angle was 2.6º with the range of 0 to 15.9º preoperatively, while the mean angle was 2.0º with the range of 0 to 8.8º postoperatively. There was statistical correlation in pelvic obliquity between before and after surgery. The mean leg length discrepancy was −8.3 before surgery, and was 0.1 after surgery. Comparing three groups of pelvic obliquity, preoperative leg length discrepancy was significantly longer in larger pelvic obliquity groups. The range of motion in hip flexion was also significantly smaller in larger pelvic obliquity groups. There were not significant differences in postoperative leg length discrepancy and other parameters. Discussion. The most important finding of present study was that postoperative pelvic obliquity related only the preoperative leg length discrepancy and the range of motion in hip flexion. We expected that pelvic obliquity is improved by correction of leg length difference. Nevertheless, there were not significant differences in postoperative leg length discrepancy. This indicated that contracture of the hip joint is contribute to pelvic obliquity more than leg length discrepancy. Previous study reported that pelvic obliquity would be improved by physical therapy 4 to 6 month after surgery. However, in our data, pelvic obliquity still remained at 1-year follow up. Moreover, postoperative pelvic obliquity related the preoperative range of motion in hip flexion. Therefore, preoperative pelvic obliquity is one of the most important parameter to make decision of postoperative leg length discrepancy. There is certain limitation in our study. We did not assess patient outcome in each groups. Extensive studies are needed to reveal correlation between pelvic obliquity and patient outcome. Conclusion. Pelvic obliquity related the preoperative leg length discrepancy and the range of motion in hip flexion. Contracture of the hip joint may cause pelvic obliquity

The MAKO Robotic arm is a haptic robotic system that can be used to optimise performance during total hip arthroplasty (THA). We present the outcome of the first 40 robotic cases performed in an NHS foundation trust along with the technique of performing robotic THA in our unit. Forty consecutive patients undergoing robotic THA (rTHA) were compared to a case matched group of patients undergoing manual THA (m-THA). 2:1 blinded case matching was performed for age, sex, implants used (Trident uncemented socket and cemented Exeter stem, Stryker Mahwah, NJ, US) and surgeon grade. Comparisons were made for radiological positioning of implants, including leg length assessment, and patient reported functional outcome (PROMS). Pre- and post-operative radiographs were independently analysed by 2 authors. All patients underwent THA for a primary diagnosis of osteoarthritis. No significant difference between groups was identified for post-operative leg length discrepancy (LLD) although pre-operatively a significantly higher LLD was highlighted on the MAKO group, likely due to patient selection. Significantly lower post-operative socket version was identified in the MAKO cohort although no difference in post-operative cup inclination was noted. However, there was significantly larger variance in post-op LLD (p=0.024), cup version (p=0.004) and inclination (p=0.05) between groups indicating r-THA was significantly less variable (Levene's test for homogeneity of variance). There was no significant difference in the number of cases outside of Lewinnek's ‘safe’ zone for inclination (p=0.469), however, there were significantly more cases outside Lewinnek's ‘safe’ zone for version (12.5% vs 40.3%, p=0.002) in the m-THA group. We report the commencement of performance of MAKO robotic THA in an NHS institution. No problems with surgery were reported during our learning curve. Robotic THA cases had less variability in terms of implant positioning suggesting that the MAKO robot allows more accurate, less variable implant positioning with fewer outliers. Longer term follow-up of more cases is needed to identify whether this improved implant positioning has an effect on outcomes, but the initial results seem promising

Introduction. Osteogenesis imperfect (OI) is a geno- and phenotypically heterogeneous group of congenital collagen disorders characterized by fragility and microfractures resulting in long bone deformities. OI can lead to progressive femoral coxa vara from bone and muscular imbalance and continuous microfracture about the proximal femur. If left untreated, patients develop Trendelenburg gait, leg length discrepancy, further stress fracture and acute fracture at the apex of the deformity, impingement and hip joint degeneration. In the OI patient, femoral coxa vara cannot be treated in isolation and consideration must be given to protecting the whole bone with the primary goal of verticalization and improved biomechanical stability to allow early loading, safe standing, re-orientation of the physis and avoidance of untreated sequelae. Implant constructs should therefore be designed to accommodate and protect the whole bone. The normal paediatric femoral neck shaft angle (FNSA) ranges from 135 to 145 degrees. In OI the progressive pathomechanical changes result in FNSA of significantly less than 120 degrees and decreased Hilgenreiner epiphyseal angles (HEA). Proximal femoral valgus osteotomy is considered the standard surgical treatment for coxa vara and multiple surgical techniques have been described, each with their associated complications. In this paper we present the novel technique of controlling femoral version and coronal alignment using a tubular plate and long bone protection with the use of teleoscoping rods. Methodology. After the decision to operate had been made, a CT scan of the femur was performed. A 1:1 scale 3D printed model (AXIAL3D, Belfast, UK) was made from the CT scan to allow for accurate implant templating and osteotomy planning. In all cases a subtrochanteric osteotomy was performed and fixed using a pre-bent 3.5 mm 1/3 tubular plate. The plate was bent to allow one end to be inserted into the proximal femur to act as a blade. A channel into the femoral neck was opened using a flat osteotome. The plate was then tapped into the femoral neck to the predetermined position. The final position needed to allow one of the plate holes to accommodate the growing rod. This had to be determined pre operatively using the 3D printed model and the implants. The femoral canal was reamed, and the growing rod was placed in the femur, passing through the hole in the plate to create a construct that could effectively protect both the femoral neck and the full length of the shaft. The distal part of the plate was then fixed to the shaft using eccentric screws around the nail to complete the construct. Results. Three children ages 5,8 and 13 underwent the procedure. Five coxa vara femurs have undergone this technique with follow-up out to 62 months (41–85 months) from surgery. Improvements in the femoral neck shaft angle (FNSA) were av. 18. o. (10–38. o. ) with pre-op coxa vara FNSA av. 99. o. (range 87–114. o. ) and final FNSA 117. o. (105–125. o. ). Hilgenreiner's epiphyseal angle was improved by av. 29. o. (2–58. o. ). However only one hip was restored to <25. o. In the initial technique employed for 3 hips, the plates were left short in the neck to avoid damaging the physis. This resulted in 2 of 3 hips fracturing through the femoral neck above the plate at approximately 1 year. There were revisions of the 3 hips to longer plates to prevent intra-capsular stress riser. All osteotomies united and both intracapsular fractures healed. No further fractures have occurred within the protected femurs and no other repeat operations have been required. Conclusions. Surgical correction of the OI coxa vara hip is complex. Bone mineral density, multiplanar deformity, a desire to maintain physeal growth and protection of the whole bone all play a role in the surgeon's decision making process. Following modifications, this technique demonstrates a novel method in planning and control of multiplanar proximal femoral deformity, resulting in restoration of the FNSA to a more appropriate anatomical alignment, preventing long bone fracture and improved femoral verticalization in the medium term follow-up

Aims. Our retrospective analysis reports the outcome of patients operated for slipped capital femoral epiphysis using the modified Dunn procedure. Results, complications, and the need for revision surgery are compared with the recent literature. Methods. We retrospectively evaluated 17 patients (18 hips) who underwent the modified Dunn procedure for the treatment of slipped capital femoral epiphysis. Outcome measurement included standardized scores. Clinical assessment included ambulation, leg length discrepancy, and hip mobility. Radiographically, the quality of epiphyseal reduction was evaluated using the Southwick and Alpha-angles. Avascular necrosis, heterotopic ossifications, and osteoarthritis were documented at follow-up. Results. At a mean follow-up of more than nine years, the mean modified Harris Hip score was 88.7 points, the Hip Disability and Osteoarthritis Outcome Score (HOOS) 87.4 , the Merle d’Aubigné Score 16.5 points, and the UCLA Activity Score 8.4. One patient developed a partial avascular necrosis of the femoral head, and one patient already had an avascular necrosis at the time of delayed diagnosis. Two hips developed osteoarthritic signs at 14 and 16 years after the index operation. Six patients needed a total of nine revision surgeries. One operation was needed for postoperative hip subluxation, one for secondary displacement and implant failure, two for late femoroacetabular impingement, one for femoroacetabular impingement of the opposite hip, and four for implant removal. Conclusion. Our series shows good results and is comparable to previous published studies. The modified Dunn procedure allows the anatomic repositioning of the slipped epiphysis. Long-term results with subjective and objective hip function are superior, avascular necrosis and development of osteoarthritis inferior to other reported treatment modalities. Nevertheless, the procedure is technically demanding and revision surgery for secondary femoroacetabular impingement and implant removal are frequent. Cite this article: 2020;1-4:80–87

We investigated whether a novel, real-time fluoroscopy based navigation system optimized component positioning and leg length in fluoroscopically aided Direct Anterior Approach Total Hip Arthroplasty (DAA-THA). We retrospectively reviewed 75 fluoroscopically assisted DAA-THA performed by a single surgeon: 37 procedures used the software intraoperatively to overlay anteversion, inclination, and leg length information over the existing fluoroscopic radiograph with the aim of enhancing component positioning. The control group consisted of 38 procedures from the single surgeon's patient pool who had undergone non-navigated fluoroscopic assisted DAA-THA one month prior to the system's trial. We used the software to compute each data point on an immediate post operative AP radiograph to replicate the intra operative measurement process. Our results demonstrate that the navigation group measurements were significantly closer to the target numbers with less variation. The mean values were significantly closer to target values anteversion (control: 14°, navigated: 19.1°), inclination (control: 37.7°, navigated: 40.8°) and leg length discrepancy (control: 4.7mm, navigated: 0.1mm). The mean difference from target value were also statistically significant: for anteversion (control: −6.0°, navigated: −0.9°), inclination (control: −2.3°, navigated: 0.8°) and leg length discrepancy (control: 2.7°, navigated: −1.9°). In addition, surgical time was shorter in the navigation group (75.7 vs. 74 minutes; p=0.001). The p values were all statistically significant (anteversion 0.0001, inclination 0.0019, LLD < 0.001 and surgical time 0.001). The real-time feedback and calculations provided by the navigation software provided a reproducible precision for component positioning and leg length measurement during DAA-THA. For any figures or tables, please contact authors directly

Aims. The aims of this study were to examine the rate at which the positioning of the acetabular component, leg length discrepancy and femoral offset are outside an acceptable range in total hip arthroplasties (THAs) which either do or do not involve the use of intra-operative digital imaging. Patients and Methods. A retrospective case-control study was undertaken with 50 patients before and 50 patients after the integration of an intra-operative digital imaging system in THA. The demographics of the two groups were comparable for body mass index, age, laterality and the indication for surgery. The digital imaging group had more men than the group without. Surgical data and radiographic parameters, including the inclination and anteversion of the acetabular component, leg length discrepancy, and the difference in femoral offset compared with the contralateral hip were collected and compared, as well as the incidence of altering the position of a component based on the intra-operative image. Results. Digital imaging took a mean of five minutes (2.3 to 14.6) to perform. Intra-operative changes with the use of digital imaging were made for 43 patients (86%), most commonly to adjust leg length and femoral offset. There was a decrease in the incidence of outliers when using intra-operative imaging compared with not using it in regard to leg length discrepancy (20% versus 52%, p = 0.001) and femoral offset inequality (18% versus 44%, p = 0.004). There was also a difference in the incidence of outliers in acetabular inclination (0% versus 7%, p = 0.023) and version (0% versus 4%, p = 0.114) compared with historical results of a high-volume surgeon at the same centre. Conclusion. The use of intra-operative digital imaging in THA improves the accuracy of the positioning of the components at THA without adding a substantial amount of time to the operation. Cite this article: Bone Joint J 2018;100B(1 Supple A):36–43

Hemiarthroplasty (HA) and total hip arthroplasty (THA) have both been well described as effective methods of management for displaced femoral neck fractures in the elderly. THA has superior functional outcomes and lower long-term revision rates, while HA is associated with lower dislocation rates and faster operative times. While HA remains an appropriate management option in low-demand patients, it is commonly complicated by acetabular erosion. However, there is no consensus about the preferred method of treatment in self-sufficient, physically active patients with normal cognition. The aim of this study was to evaluate the impact of age in geriatric patients with acetabular wear after bipolar HA. We retrospectively reviewed the records of all cases of femoral neck fractures treated with bipolar HA in our institution, during the period 2013 – 2020. According to the age at the time of fracture, patients were separated in 3 groups: Group A (age 70 – 75), group B (age 75 – 80) and group C (age > 80). Acetabular wear was defined as failure of the acetabulum, which needed revision to THA. A total of 1410 patients (861 females and 549 males, mean age 77,2 years) were included in the study. 359 patients were included in Group A, 592 in Group B and 459 in Group C. Mean follow-up was 3.2 years. There were no significant differences in sex distribution, injury side, fracture pattern, BMI, ASA score, bipolar head diameter and leg length discrepancy among the 3 groups. The incidence of acetabular wear and need for revision to THA was 6.13%, 4.22% and 1.96% respectively (p = 0.009). The higher rate of acetabular wear in patients less than 75 years suggests that THA is a more viable option for these patients. In group 75–80 years old decision for HA or THA should be made upon patient's activity status and biological age while above the age of 80 years old, Hemi seems to be the preferred solution

Introduction. One of the more common complaints from patients in their post-operative total knee arthroplasty (TKA) is the perceived feeling of the operative leg feeling longer than the non-operative leg. Studies have shown that the leg length discrepancies may occur in up to 80% of patients following unilateral TKA patients. The purpose of this study was to determine the incidence of leg length discrepancy (LLD) after primary TKA as well as determine the correlation between deformity and incidence of LLD. Methods. We retrospectively reviewed 1108 patients who underwent a primary unilateral TKA at a single institution. 97 patients were excluded for lack of imaging, prior total hip replacement or body mass index greater than 40 kg/m2. Hip to ankle biplanar radiographs were obtained pre-operative and 6 weeks postoperatively for all patients. Two independent observers measures leg length, femur length, tibia length, overall alignment and deformity present for all radiographs. Results. 1,101 patients were included. Mean overall lengthening was 3.4 mm [Range −21 to 22.8mm; SD 7.4] with 81% of limbs lengthened. In our cohort, 9% of patients had LLD greater than 10 mm and 43% of patients had LLD of more than 5mm after TKA. Post-operative radiographic LLD was associated with increased pre-operative LLD (P<.001) and with female gender (p=0.03). Patients with pre-operative valgus deformity were more likely to have an increased lengthening of greater than 5mm compared to patients with varus deformity (OR:1.66). Conclusion. 43% of patients will have a LLD >5mm following correction of deformity and ligament balances in knee replacement surgery. Surgeons should be aware and this should be reviewed with patients as part of their expectations of surgery. For figures, tables, or references, please contact authors directly

Periprosthetic fractures (PPF) of the femur following total hip arthroplasty represent a significant complication with a rising incidence. The commonest subtype is Vancouver B2 type, for which revision to a long uncemented tapered fluted stem is a widely accepted management. In this study we compare this procedure to the less commonly performed cement-in-cement revision. All patients undergoing surgical intervention for a Vancouver B2 femoral PPF in a cemented stem from 2008 – 2018 were identified. We collated patient age, gender, ASA score, BMI, operative time, blood transfusion requirement, change in haemoglobin (Hb) level, length of hospital stay and last Oxford Hip Score (OHS). Radiographic analysis was performed to assess time to fracture union and leg length discrepancy. Complications and survivorship of implant and patients were recorded. 43 uncemented and 29 cement-in-cement revisions were identified. There was no difference in patient demographics between groups. A significantly shorter operative time was found in the cement-in-cement group, but there was no difference in transfusion requirement, Hb change, or length of hospital stay. OHS was comparable between groups. A non-significant increase in overall complication rates was found in the revision uncemented group, with a significantly higher dislocation rate. Time of union was comparable and there were no non-unions in the cement-in-cement group. A greater degree of stem subsidence was found in the uncemented group. There was no difference in any revision surgery required in either group. Three patients in the uncemented group died in the perioperative period, compared to none in the cement-in-cement group. With appropriate patient selection, both cement-in-cement and long uncemented tapered stem revision represent appropriate treatment options for Vancouver B2 fractures

Introduction. We have previously published limb lengthening using external fixation in pathological bone diseases. We would like to report a case series of femoral lengthening using the PRECICE system in a similar pathological group especially looking at it's feasibility and complications. Materials and Methods. This is a case series of four patients, two patients with osteogenesis imperfecta and two with Ollier's disease, who underwent femoral lengthening via distraction osteogenesis using the PRECICE intramedullary nail system. It was a retrospective study from a prospective database from clinical records and radiographs. Results. The mean age at the time of surgery was 15.5 years, the mean preoperative leg length discrepancy was 30mm, and the mean distraction distance achieved was 28.75mm. Since these patients were of shorter heigh, limb lengthening was considered. All 4 patients had successful insertion of the nail. The outcomes noted from the 4 patients are collated, with several complications occurring including delayed femoral union, fixed flexion deformity of the hip, persisting pain and quadriceps weakness. Those with Ollier's disease underwent an increased rate of distraction to prevent premature healing. The implications of long-term bisphosphonate therapy in OI are discussed with regards to the risk of delayed femoral union and intra-operative fracture. Conclusions. Intramedullary femoral lengthening in pathological bone disease is possible, but the surgeon needs to give attention to certain details. The regenerate formation is based on the background pathology irrespective of the hardware used. There is much more compliance with the nail technique

Introduction. Leg length discrepancy (LLD) in patients with unilateral developmental dysplasia of the hip (DDH) can be problematic for both patients and surgeons. Patients can acquire gait asymmetry, back pain, and arthritis. Surgical considerations include timing of correction and arthroplasty planning. This study audits standing long leg films performed at skeletal maturity in our patients. The aim of this study is to identify if surgical procedure or AVN type could predict the odds of needing an LLD Intervention (LLDI) and influence our surveillance. Materials and Methods. Hospital database was searched for all patients diagnosed with DDH. Inclusion criteria were patients with appropriately performed long leg films at skeletal maturity. Exclusion criteria were patients with non DDH pathology, skeletally immature and inadequate radiographs. All data was tabulated in excel and SPSS was used for analysis. Traumacad was used for measurements and AVN and radiologic outcome grades were independently classified in duplicate. Results. 110 patients were identified. The mean age of follow-up was 15 years with final average LLD of 1mm(±5mm). The DDH leg tended to be longer and length primarily in the femur. 31(28.2%) patients required an LLDI. 19 Patients had a final LLD >1.5cm. There was no statistical significant difference in the odds of needing an LLDI by type of surgical procedure or AVN. AVN type 4 was associated with greatest odds of intervention. The DDH leg was more likely to require ipsilateral epiphysiodesis or contralateral lengthening in Type 1 and 2 AVN. Conclusions. The DDH leg tends to be longer, leg lengths should be monitored, and leg length interventions are frequently required irrespective of previous DDH surgical procedure or the presence of AVN

Neck of femur fractures are a common presentation and certain patients can be managed with a total hip replacement. To receive a total hip replacement the pelvic X-rays should be templated as per AO guidelines and a common way this is performed is by including a calibration marker on the X-ray. The aim of this study is to assess and improve upon the use of the calibration marker. Details of patients admitted with a neck of femur fracture from January 1st 2018 until December 31st 2018 were gathered and used to review each initial X-ray and determine if a calibration marker was included. 376 patients were admitted with a neck of femur fracture over the one year period. 36% of patients did not have a calibration marker on their initial pelvic X-ray and 11% did not have a chest X ray. 215 patients had an intracapsular fracture and 39 went on to have a total hip replacement. 12 patients were lacking a calibration marker on their original X ray and required a repeat X ray. After a poster was placed in the radiographer booth acting as a visual aid, the use of a calibration marker improved from 62% to 70%. Calibration markers are useful tools which can aid the pre-operative planning for hip replacement surgeries shortening operative time, increase precision and reduce prosthetic loosening, lowers the risk of peri-prosthetic fractures, reduce leg length discrepancy and ensure the required implants are available. If a marker is not included on the initial X-rays, and a patient has a neck of femur fracture which requires a joint replacement, they may have to have additional X-rays performed as was the case for 12 patients in this study. This process leads to possible delays in surgery, additional radiation and increased healthcare costs

Introduction. Pixel Value Ratio (PVR) is a radiographic measure of the relative density of the regenerate to the adjacent bone. This has been reported as an objective criterion for regenerate healing and a guide for when to allow full weight bearing (FWB) in lengthening with intramedullary telescopic nails. The threshold for which magnitude of PVR is adequate to allow bearing full weight is not yet agreed. The aim of this study was to identify from our cohort of adult limb lengthening patients the time to FWB following lengthening, the PVR at this point, and how this compared with the recommended values in the literature. Materials and Methods. A retrospective database review identified 30 adult patients treated with the PRECICE femoral nail by two senior authors. Time from completion of lengthening to instruction to fully weight bear was noted. The PVR was calculated for each cortex on plain radiographs taken at each postoperative visit following completion of lengthening. Significance was set at p <0.05. Results. The median age was 30.5 years (IQR 22.5 – 42.5), 19 male and 11 female patients were included. The underlying cause of shortening was post traumatic in 12 (40%) with the remaining due to a wide variety of causes including congenital, infective, and idiopathic leg length discrepancies. Twenty-two nails were antegrade and the mean distance lengthened was 42 mm. Median time from completion of lengthening to full weight bearing was 42 days (IQR 28 – 69). The overall mean PVR at FWB was 0.79. Each surgeon had differing protocols for weightbearing, however there was no statistical difference between time to weight bearing, nor the mean PVR at FWB. There were no implant failures, shortening, or regenerate fractures. Conclusions. We report on our cohort of adult patients treated with intramedullary lengthening nails with a mean PVR of 0.79 at time of full weightbearing. This is considerably lower than the values reported in the literature ranging from 0.90 to 0.93. We therefore suggest that weightbearing following lengthening nails can be permitted earlier than previously reported without an increased risk of complication

Introduction. Legg-Calvé-Perthes disease (LCPD) often results in femoral head deformity and leg length discrepancy (LLD). Objective of this study was to analyse femoral morphology in LCPD patients at skeletal maturity to assess where the LLD originates, and evaluate the effect of contralateral epiphysiodesis for length equalisation on proximal and subtrochanteric femoral lengths. Materials and Methods. All patients treated for LCPD in our institution between January 2013 and June 2020 were retrospectively reviewed. Patients with unilateral LCPD, LLD of ≥5mm 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 LCPD side and unaffected side. Furthermore, we compared leg length measurements between patients who did and who did not have a contralateral epiphysiodesis. Results. 79 patients were included, 21/79 underwent contralateral epiphysiodesis for leg length correction. In the complete cohort the average LLD was 1.8cm (95% CI 1.5 – 2.0), average ATD difference was 1.8cm (95% CI −2.1 – −1.9) and average subtrochanteric difference was −0.2cm (95% CI −0.4 – 0.1). In the epiphysiodesis group the average LLD before epiphysiodesis was 2.7 (1.3 – 3.4) cm and 1.3 (−0.5 – 3.8) cm at skeletal maturity. In the non-epiphysiodesis group the average LLD was 2.0 (0.5 – 5.1), p=0.016. The subtrochanteric region on the LCPD side was significantly longer at skeletal maturity in the epiphysiodesis group compared to the non-epiphysiodesis group: −1.0 (−2.4 – 0.6) versus 0.1 (−1.0 – 2.1), p<0.001. Conclusions. This study concludes that LLD after LCPD originates from the proximal segment only. In patients who had had a contralateral epiphysiodesis, the subtrochanteric femoral region was significantly longer on the LCPD side. These anatomical changes need to be considered by paediatric surgeons when advising leg length equalisation procedures, and by arthroplasty surgeons when LCPD patients present for hip arthroplasty

Purpose. Leg length discrepancy after total hip arthroplasty (THA) sometimes causes significant patient dissatisfaction. In consideration of the leg length after THA, leg length discrepancy is often measured using anteroposterior (AP) pelvic radiography. However, some cases have discrepancies in femoral and tibial lengths, and we believe that in some cases, true leg length differences should be taken into consideration in total leg length measurement. We report the lengths of the lower limb, femur, and tibia measured using the preoperative standing AP full-leg radiographs of the patients who underwent THA. Materials and methods. From August 2013 to February 2017, 282 patients underwent standing AP full-leg radiography before THA. Of the patients, 33 were male and 249 were female. The mean age of the patients was 65.7±9.4 years. We measured the distances between the center of the tibial plafond and lesser trochanter apex (A-L), between the femoral intercondylar notch and lesser trochanter (K-L), and between the centers of the tibial plafond and intercondylar spine of the tibia (A-K) on standing AP full-leg radiographs before THA operation. We examined the differences in leg length and the causes of these discrepancies after guiding the difference between them. Results. The mean A-L was 674±44 mm on the right and 677±43 mm on the left. The mean difference between the left and the right was 6.2±7 mm. The differences of ≥5 and ≥10 mm between the left and right were confirmed in 131 (46%) and 39 cases (14%), respectively. The mean K-L was 343±23 mm on the right and 343±23 mm on the left, with a mean difference of 4.4±4 mm. The lateral differences of ≥5 and ≥10 mm were confirmed in 88 (31%) and 22 (8%), respectively. The mean A-K was 325±22 mm on the right and 327±22 mm on the left, with a mean difference of 4±4.5 mm. The differences of ≥5 and ≥10 mm between the left and right were confirmed in 24 (9%) and 67 cases (%), respectively. Discussion. Considering the total length of the lower limbs beyond the little trochanter and the leg length after THA, we confirmed that 46% of the leg length differences of ≥5 mm were admitted to 14%. Thus, THA appeared effective. Perthes head, Crowe classifications 3 and 4, history of childhood paralysis, and so on may be factors for leg length differences beyond the lesser trochanter. Conclusion. We think that it would be preferable to prepare a preoperative plan to measure leg length after THA by measuring the total length of the lower extremity before surgery and determining the difference between the left and right sides

Total hip replacement procedures are among the most frequent surgical interventions in all industrialized countries. Although it is a routine operationliterature reports that important parameters regarding for example cup orientation and leg length discrepancy often turn out to be not satisfying after surgery. This paper presents a novel concept to improve the reproducibility and accuracy for implantation of cup and stem prosthesis at exactly the desired locations. Existing computer- based commercial products either offer software solutions for just pre-operative planning, or imageless navigation systems that are only used during surgery in the operating theatre. The innovation of our approach is based on an integrated computer-assisted solution that combines pre-operative planning and intra-operative navigation to support THR procedures. The software for pre-operative planning can process both, 3D CT images and standard 2D x-ray images. A custom-built navigation system using optical 3D localizing technology has been developed to transfer planning results to the OR. The main objective of our approach is to implant the artificial joint in a way to restore the natural anatomy of the joint before surgery as close as possible, or with exactly planned modifications. In particular, cup inclination, cumulative anteversion of cup and stem, CCD angle and lateral offset, centre of rotation, leg length discrepancy, and joint range of motion are considered. It is not necessary to determine numerical values for all of these parameters because our approach uses a unique procedure to record the natural anatomical situation by combining pre-operative planning and intra-operative navigation, and subsequently supports implantation of the prosthesis components by surgical navigation in order to restore this situation. In case planar 2D x-ray images are used for pre-operative planning accurate scaling of these images is a prerequisite for exact determination of relevant parameters. The patient-specific scaling factor depends on the distance of the hip joint rotation centre from the x-ray detector or film. We have designed a low-cost localization system to be mounted close to the x-ray apparatus. It localizes the 3D position of the rotation centre by small motions of the leg and eliminates uncertainties of conventional methods that are caused by improper positioning of a calibration body. Easy and robust setup and application have been key objectives for the development of our custom-built navigation system. Acquisition of intraoperative parameters for example includes the determination of the acetabular centre axis by localizing selected landmarks at the acetabular rim. Intra-operative parameters are combined with pre-operative parameters without needing sophisticated matching procedures with the pre-operative images. A preliminary surgical workflow that will be detailed in the conference presentation has been designed for evaluation of the concept using sawbones models. Based on the promising results of our laboratory tests we have started to prepare first clinical experiments in close cooperation with surgeons

Aims. Studying the indications for revision total hip arthroplasty (THA) may enable surgeons to change their practice during the initial procedure, thereby reducing the need for revision surgery. The aim of this study was to identify and describe the potentially avoidable indications for revision THA within five years of the initial procedure. Patients and Methods. A retrospective review of 117 patients (73 women, 44 men; mean age 61.5 years (27 to 88)) who met the inclusion criteria was conducted. Three adult reconstruction surgeons independently reviewed the radiographs and medical records, and they classified the revision THAs into two categories: potentially avoidable and unavoidable. Baseline demographics, perioperative details, and quality outcomes up to the last follow-up were recorded. Results. A total of 60 revision THAs (51.3%) were deemed potentially avoidable and 57 (48.7%) were deemed unavoidable. The following were identified as avoidable factors: suboptimal positioning of the acetabular component (29; 48%), intraoperative fracture or a fracture missed on an intraoperative radiograph (20; 33%), early (less than two weeks) aseptic loosening (seven; 11.7%), and symptomatic leg length discrepancy of > 1 cm (four; 6.7%). Conclusion. A surprisingly large proportion of acute revision THAs are potentially avoidable. Surgeons must carefully evaluate the indications for revision THAs in their practice and identify new methods to address these issues. Cite this article: Bone Joint J 2019;101-B(6 Supple B):97–103

Exeter Trauma Stem (ETS) is one of the most common implants used for treating displaced intracapsular hip fractures in the UK. We previously performed a radiographic audit of these implants which showed good placement was difficult. This was in particular relation to leg length discrepancy (LLD). This study reviewed the clinical outcomes of these patients, in particular looking at the relation of leg length discrepancy to outcome. We performed a clinical review of patients at 3 months and 1 year post ETS for hip fracture. Oxford hip score (OHS), Trendelenberg test, Visual Analogue Score (VAS) and walking aids required were recorded. Leg length discrepancy was determined radiographically on initial post op X-ray. This was recorded as Even (+/− 5mm), 6-10mm Long and >10mm long. Seventy-two patients were reviewed at 3 months and 21 at 1 year. Mean VAS was 1.6. At 3 months 66% were Trendelenberg positive. Of those Trendelenberg positive at 3 months only 42% remained positive at 1 year. Mean OHS at 3months and 1 year was 30.8 and 32.1 respectively. On radiographic review 38 implants were Even, 24 were 6-10mm Long and 10 implants were >10mm Long. There was no correlation between leg length discrepancy and either VAS or Trendelenberg test. 45 patients ambulated independently pre-op. Of these only 8 ambulated independently post-op, 18 used a stick and 11 a Zimmer frame. There was no correlation between post operative leg length discrepancy and either Visual Analogue Score, OHS or Trendelenberg test. Mean pain score was very low. There was however almost 10% of patients with a VAS greater than 6. 80% of patients dropped one ambulatory level post-op, this is consistent with previous studies. The ETS provides good pain relief with a low complication rate in the vast majority of patients

Aim. Two stage revision is the most commonly used surgical treatment strategy for periprosthetic hip infections (PHI). The aim of our study was to assess the intra- and postoperative complications during and after two stage revision using resection arthroplasty between ex- and reimplantation. Method. In this retrospective cohort study, all patients treated with a two stage revision using resection arthroplasty for PHI were included from 2008 to 2014. During the first stage, the prosthesis was removed resulting in a resection arthroplasty without the use a PMMA spacer. During second stage, (cemented or uncemented) reimplantation of the hip prosthesis was performed. The cohort was stratified into two groups according to the length of prosthesis-free interval (≤10 weeks and >10 weeks). Data on complications during explantation, prosthesis-free interval, reimplantation, and after reimplantation was collected. The overall complication rate between both groups was compared using the chi-squared test. The revision-free and infection-free survival was estimated using Kaplan-Meier survival analysis. Results. Overall, 93 patients with hip PJI treated with two-stage revision performing resection arthroplasty were included, 49 had a prosthesis-free interval of ≤10 weeks, and 44 an interval of >10 weeks. A total of 146 complications was documented in the cohort. Patients were followed-up for a mean duration of 42.7 months, range: 13.1 – 104.6 months. Blood loss during reimplantation [n=25], blood loss during explantation [n=23], persistent infection during prosthesis-free interval [n=16], leg length discrepancy [n=13], and reinfection [n=9] were the most common complications. No complication showed a statistically significant difference between both groups except for wound healing disorder after reimplantation, which was more often reported in the group with > 10 weeks interval (p=0.009). A statistically significant increase of periprosthetic bone fractures (p=0.05), blood loss (p=0.039), and total number of complications (p=0.008) was seen with increasing acetabular bone defects (after Paprosky). Infection-free survival rate at 24 months was 93.9% (95% CI: 87.2 – 100) in the group with ≤10 weeks interval and 85.9% (95% CI: 75.4 – 96.4) with an interval of > 10weeks. Conclusions. After two years of follow-up, the infection-free survival rate using resection arthroplasty during two stage revision for PHI was higher in the group with ≤10 weeks interval compared to the group with >10 weeks interval. The most common complications during and after a two stage revision using resection arthroplasty were blood loss during the two surgeries, persistent infection during the prosthesis-free interval, leg length discrepancy, and reinfection

Patients with hemiplegic cerebral palsy walk with a well recognised characteristic gait pattern. They also commonly have a significant leg length discrepancy which is less well appreciated. The typical equinus gait in these patients is assumed to be an integral part of the disease process of spasticity and a tendency to develop joint contractures. However an alternative explanation for the presence of an equinus deformity may be that it is a response to the development of a significant leg length discrepancy in these patients. The development of such an equinus deformity would have the effect of functionally lengthening the short hemiplegic leg. We set up a study to examine the correlation between leg length discrepancy and equinus deformity. We reviewed the gait analyses and clinical examinations of 183 patients with hemiplegic cerebral palsy. While 22% had no significant leg length discrepancy, 65% had a measured discrepancy of greater than 1cm. There was a linear correlation between age and limb length discrepancy. We also found that there was a linear relationship between leg length discrepancy and ankle equinus at the point of ground contact. We propose that the equinus deformity seen in the hemiplegic cerebral palsy patient is multifactorial and is related not only to the disease state but also to the presence of leg length discrepancy. The equinus deformity functionally lengthens the short hemiplegic leg. Indeed it may represent an attempt by these patients to functionally equalise their leg lengths. This factor must be taken into account when considering correction of an equinus deformity in patients with hemiplegic cerebral palsy in order to avoid either recurrence of the deformity or the production of functionally unequal leg lengths. We have also highlighted the presence of significant shortening of the hemiplegic leg in these patients

In the congenital hip dysplasia, patients treated with total hip replacement (THR) often report persistent disability and pain, with unsatisfactory function and quality of life. A major challenge is to restore the center of rotation of the hip and a satisfactory abduction function [1]. The position of the acetabular cup during THR might be crucial, as it affects abduction moment and motor function. Recently, several software systems have been developed for surgical planning of endoprostheses. Previously developed software called HipOp [2], which is routinely used in clinics, allows surgeons to properly position the prosthetic components into the 3D space of CT data. However, this software did not allow to simulate the articular range of motion and the condition of the abductor muscles. Our aim is to present HipOpCT, an advanced version of the software that includes 3D musculoskeletal planning, through the application to hip dysplasia patients to add knowledge in the diagnosis and treatment of such patients who need THR. 40 hip dysplasia patients received pre-operative CT scanning of pelvis and thighs and had their THR surgery planned using HipOpCT. The base planning includes import of CT data, positioning of prosthetic components interactively through multimodal display, as well as geometrical measurements of the implant and the host bone. The advanced planning additionally includes evaluation of femoro-acetabular impingement and calculation of leg lengths, abductor muscle lengths and lever arms through the automatic creation of a musculoskeletal model. The musculoskeletal parameters in all patients were calculated during the surgical planning, and the data were processed to evaluate pre- and post-operative differences in leg length discrepancy, length and lever arm of the abductor muscles, and how these parameters correlated. The surgical planning led to an increase in the operated leg length of 7.6 ± 5.7 mm. The variation in abductors lever arm was −0.9% ± 4.8% and significantly correlated with the variation in the operated leg length (r = −0.49), pre-operative leg length discrepancy (r = 0.32) and variation in abductors length (r = −0.32). The variation in abductors length was 6.6% ± 5.5%, and significantly correlated with the variation in the operated leg length (r = 0.92), post-operative leg length discrepancy (r = 0.37), pre-operative abductors length (r = −0.37) and variation in abductors lever arm (r = −0.32). The increase in the operated leg length was strongly correlated to the increase in abductor muscle length. Conversely, abductor lever arms slightly decreased on average, and were inversely correlated to leg length variation and abductors lengths. This interactive technology for surgical planning represent a powerful tool for orthopaedic surgeons to consider the best muscle reconstruction, and for rehabilitation specialists to achieve the best functional recovery based on biomechanical outcomes. In a parallel study, we are investigating how these advanced planning is reflected onto the function, pain and biomechanical outcome after a rehabilitation protocol is completed

Introduction. Dual mobility (DM) total hip arthroplasty (THA) prostheses are designed to increase stability. In the setting of primary and revision THA, DM THA are used most frequently for dysplasia and instability diagnoses, respectively. As the use of DM THA continues to increase, with 8,031 cases logged in the American Joint Replacement Registry from 2012–2018, characterizing in vivo damage and clinical failure modes are important to report. Methods. Under IRB-approved implant retrieval protocol, 43 DM THA systems from 41 patients were included. Each DM THA component was macroscopically examined for standard damage modes. Clinically-relevant data, including patient demographics and surgical elements, were collected from medical records. Fretting and corrosion damage grading is planned, according to the Goldberg et al. classification system. Results. In this 43-retrieved implant series, there were 23 female and 17 male patients (n=1, unknown), with an average body mass index of 29 (range, 19–49), and average ages at index and revision of 63 years (range, 34–80) and 64 years (range, 38–88), respectively. The average duration of implantation was 12.9 months (range, 0.1–72.0). Reasons for revision included infection (n=11, 26%), mechanical complication (n=10, 23%), intraprosthetic dislocation (n=6, 14%), periprosthetic fracture (n=5, 12%), pain (n=4, 9%), acetabular-associated loosening (n=3, 7%), unknown (n=3, 7%), hematoma (n=2, 5%), leg length discrepancy (n=1, 2%), and inflammatory reaction (n=1, 2%); some cases included multiple reasons for revision. On articular surfaces, scratching was the most commonly observed damage mode on all components, with more than 40% of acetabular cup and femoral heads showing scratching damage (Figure 1A). Abrasion, burnishing, and pitting damage were also observed in more than 10% of acetabular cup and acetabular liner components; further, approximately 20% of polyethylene acetabular liners exhibited edge deformation damage. On backside surfaces, polyethylene acetabular liners showed the greatest damage, with more than 60% of components exhibiting abrasion, scratching, or pitting damage (Figure 1B). Conclusion. This series showed various reasons for revision as well as in vivo damage of retrieved DM systems following short-to-midterm implantation. Damage was observed on both articular and backside surfaces of the five components of DM THA. Modularity of DM THA prostheses may amplify rates of in vivo damage. Future studies are needed to confirm these results and clinical significance. For any figures or tables, please contact the authors directly

Patients with longstanding hip fusion are predisposed to symptomatic degenerative changes of the lumbar spine, ipsilateral knee and contralateral hip. 1. In such patients, conversion of hip arthrodesis to hip replacement can provide relief of such symptoms. 2 – 4. However, this is a technically demanding procedure associated with higher complication and failure rates than routine total hip replacement. The aim of this study was to determine the functional results and complications in patients undergoing hip fusion conversion to total hip replacement, performed or supervised by a single surgeon. Twenty-eight hip fusions were converted between 1996 and 2016. Mean follow up was 7 years (3 to 18 years). The reasons for arthrodesis were trauma 11, septic arthritis 10, and dysplasia 7. The mean age at conversion was 52.4 years (26 to 77). A trochanteric osteotomy was performed in all hips. Uncemented components were used. A constrained liner was used in 7 hips. Heterotopic ossification prophylaxis was not used in this series. HHS improved a mean of 27 points (37.4 pre-op to 64.3 post-op). A cane was used in 30% of patients before conversion and 80% after. Heterotopic ossification occurred in 12 (42.9%) hips. There was 2 peroneal nerve injuries, 1 dislocation, 1 GT non-union and 1 infection. There have been 5 revisions; 2 for aseptic loosening, 1 for infection, 1 for recurrent dislocation and 1 for leg length discrepancy. Conversion of hip fusion to hip replacement carries an increased risk of heterotopic ossification and neurological injury. We advise prophylaxis against heterotropic ossification. When there is concern about hip stability we suggest that the use of a constrained acetabular liner is considered. Despite the potential for complications, this procedure had a high success rate and was effective in restoring hip function

To report the results of the intramedullary skeletal kinetic distractor (iskd) in patients with established leg length discrepancy following lower limb trauma. 12 patients with significant leg length discrepancy (> 20mm) following lower limb trauma were operated on using the iskd nail between september 2004 and december 2007. patients were followed up clinically and radiologically at minimum 18 months (mean: 27months range: 18–24 months). 8 femurs and 4 tibias were operated using the iskd nail. all patient in the series had successful completed treatements. the average leg length discrepancy was 38mm (91mm–21mm) and the average gained length was 37mm (76m–22mm). radiological union and bone consolidation were slow to occur. early weight bearing was permitted allowing earlier functional capacity. 6 patients required additional operations; 3 manipulation under anaesthesia for failed lengthening and 3 bone grafting for poor regenerate, 1 patient required more than one additional operation. The iskd nail is an effective and reliable alternative technique for correcting leg length discrepancy in patients who have suffred lower limb trauma. it appears to mimic the results achieved with the use of a fine wire external fixator or a unilateral external fixator. the convenience of a fully implanted device is substantial. the complications are frequent but manageable with standard techniques

Introduction. The direct anterior approach (DAA) for total hip arthroplasty (THA) has gained popularity in recent years. Potential advantages over other surgical approaches include less postoperative pain, fewer postoperative precautions, and quicker early recovery. It is most commonly performed in the supine position with traction tables or table mounted bone hooks to facilitate exposure. In this study, we describe a reproducible surgical technique for DAA THA in the lateral decubitus position with use of standard THA equipment and report on our results and learning curve. Methods. A prospectively collected hip repository was queried for all primary THA DAA performed in the lateral position by a single surgeon over a 4-year period from the surgeon's first case utilizing the technique. Retrospective chart review was performed to identify complications and revisions. Modified Harris Hip Score (mHHS) was collected pre-operatively and again at 1-year post-operative. Radiographic parameters including were measured on the 1-year postoperative radiographs. Results. Three hundred forty-one hips were identified in patients over 18 years of age with 337 hips meeting our inclusion/exclusion criteria. A total of 257 hips (76%) had a minimum of 1-year follow-up. 212 of 225 hips (94%) with available mHHS data achieved MCID, defined as mHHS change of > 8. Mean surgical time was 88 ± 16 minutes. Radiographic evaluation demonstrated reproducible results with mean radiographic side to side leg length discrepancy of 2.6 ± 5.9mm and femoral offset difference of 0.2 ± 4.9mm. Among patients with adequate postoperative radiographs, 234 of 243 (96%) had acetabular component positions within Lewinnick's safe zone. 3 hips (0.9%) required revision THA within the first year postoperatively. There were no dislocations and there was no learning curve detected in terms of operative time, blood loss, complication rate or acetabular component position. Discussion. Critics of DAA THA cite its long learning curve with increased risk of complications as an argument against its widespread use. In this study, we have described a safe and efficient technique for performing THA via the DAA in the familiar lateral decubitus with the use of a standard operating table, positioning devices and THA instrumentation. Our results demonstrate excellent acetabular component placement and low rates of complications within the first postoperative year. Conclusion. DAA THA can be performed safely and efficiently in the lateral decubitus position without a specialized table or instrumentation. Surgeon familiarity with patient position and instruments using the technique presented here may be associated with a shorter procedural learning curve

Introduction: Percutaneous epiphysiodesis is a well established procedure in the treatment of leg length discrepancy. Many techniques have been described ranging from an open technique to the more recently described percutaneous technique. This study assesses the percutaneous single portal technique, in combined distal femoral and proximal tibial lower limb epiphysiodesis, performed by a single surgeon. Methods: We performed a retrospective review of cases performed in a single institution by a single surgeon from 1994 to present. A total of 45 combined epiphysiodesis were performed. 40 patients qualified for the study group with at least 2 years follow up. There were 19 female and 21 male patients, with the operative side equally shared between left and right. Results: The mean predicted leg length discrepancy using the Mosley Straight Line Graph was 2.43 cm. The mean final leg length discrepancy, at an average follow up of 31 months, was 1.5 cm with a range of 0 to 2.81 cm. There were no angular deformities at follow up. One female patient had a knee effusion which resolved spontaneously. One male patient complained of anterior knee pain initially post surgery however this resolved at final follow up without treatment. The majority of patients (n=34) were inpatients, however more recently this procedure has been successfully carried out as a day case (n=6). Discussion: Percutaneous epiphysiodesis has been accepted as a standard technique to treat leg length discrepancy of 2 cm to 5 cm. Several techniques have been described in the literature with varying complication rates. This study shows that single portal combined epiphysiodesis is successful and has a relatively low complication rate

INTRODUCTION. Childhood diseases involving the proximal femoral epiphysis often cause abnormalities that can lead to end-stage arthritis at a relatively young age and the need for total hip arthroplasty (THA). The young age of these patients makes hip resurfacing arthroplasty (HRA) an alternative and favorable option due to the ability to preserve femoral bone. Patients presenting with end-stage hip arthritis as sequelae of childhood diseases such as Legg-Calves-Perthes (LCP) and slipped capital femoral epiphysis (SCFE) pose altered femoral anatomy, making HRA more technically complicated. LCP patients can result in coxa magna, coxa plana and coxa breva causing altered femoral head-to-neck ratio. There can also be acetabular dysplasia along with the proximal femoral abnormalities. SCFE patients have altered femoral head alignment. In particular, the femoral head is rotated medially and posteriorly, reducing the anterior and lateral offset. Additionally, many of these patients have retained hardware, making resurfacing more complicated. We report findings of a cohort of patients, with history of either LCP or SCPE who underwent HRA to treat end-stage arthritis. METHODS. Data was retrospectively collected for patients who had HRA for hip arthritis as a result of either LCP (n=67) or SCFE (n=21) between 2004 and 2014 performed by two surgeons. Demographic information, clinical examination and improvement was collected pre and postoperatively. Improvement was determined using Harris Hip Scores (HHS) and UCLA activity scores. Anteroposterior radiographs were measured pre and postoperatively to determine leg length discrepancy. Radiographs were inspected postoperatively for radiolucent lines, implant loosening and osteolysis. Kaplan-Meier survivorship for freedom from reoperation for any reason was calculated. Paired student t-tests were used to compare groups. RESULTS. The average age at the time of surgery was 44 years (11.8–68), with an average follow-up of 3.7 years (.22–11.2). Retained hardware was present in a total of 5 patients, 1 LCP and 4 SCFE. Preoperative HHS was 58.3 (33–83), which increased significantly to 94.9 (55–100) at the most recent postoperative timepoint (p<.0001). The most recent UCLA activity score was 7 (1–10). Average leg length discrepancy preoperatively was 7.5mm (0–20), which significantly improved to 0.6mm (0–7.5) postoperatively (p<.0001). At most recent follow-up, metal ion testing revealed median chromium level of 2.3 parts per billion (ppb, 1–7.7) and median cobalt level of 1.5 (0–9.2). There were three failures in the group with 1 LCP due to instability at 2.7 years, and 2 SCFE due to femoral neck fracture at 1 month in one and clinical failure due to unexplained pain at 5.5 years in one. Revision surgery was done in 2 patients, 1 LCP and 1 SCFE. Radiographic examination of all non-failure HRA patients revealed implants to be in good alignment with no indication of implant loosening at the most recent postoperative timepoint. Kaplan-Meier survivorship for freedom from revision was 96.2 at 5 years. CONCLUSION. The findings demonstrated increase in functional outcomes in patients who underwent HRA for osteoarthritis associated with LCP and SCFE. There was no increase in complications including femoral neck fracture or implant loosening despite technical challenges of the procedure

INTRODUCTION. Leg length discrepancy following total hip arthroplasty (THA) can be functionally disabling for affected patients and can lead on to litigation issues. Assessment of limb length discrepancy during THA using traditional methods has been shown to produce inconsistent results. The aim of our study was to compare the accuracy of navigated vs. non navigated techniques in limb length restoration in THA. METHODS. A dataset of 160 consecutive THAs performed by a single surgeon was included. 103 were performed with computer navigation and 57 were non navigated. We calculated limb length discrepancy from pre and post op radiographs. We retrieved the intra-operative computer generated limb length alteration data pertaining to the navigated group. We used independent sample t test and descriptive statistics to analyse the data. RESULTS. The two subgroups were matched for age, diagnosis and preoperative leg length discrepancy. The mean age was 69.12 (37–89, SD-8.3) and the mean BMI was 29 (19–44, SD-5.03). The mean post op limb length discrepancy in the non navigated group was 5 mm (SD-6) as compared to mean of 3.5mm (SD-6.5) for the computer navigated group. This difference was statistically significant (p<0.04). 18% of patients in the non navigated group had a limb length discrepancy of >10 mm as compared to 12% in the navigated group. There was no statistically significant difference between the computer predicted leg length alterations and those measured on radiographs. (p>0.15). DISCUSSION & CONCLUSION. The use of Computer navigation in THA can be useful in reducing errors related to leg length discrepancy. It helps in reducing the rates of unacceptably high discrepancies. In our experience, the results of this technique were predictable and reproducible. We intend to continue using this tool for our total hip arthroplasties

Background. Leg length discrepancy real or perceived remains an important source of patient dissatisfaction after a total hip replacement. Pre-operative templating and intra-operative measurement has to be used to ensure an accurate restoration of the normal centre of rotation of the hip as well as equal leg lengths. Theoretically more bone has to be resected from the femur to maintain the centre of the femoral head in the same location. This is due to a smaller size of the prosthetic femoral head compared to the native femoral head. It was postulated that this was an accurate predictor of leg length after a total hip replacement. Methods. 56 consecutive patients who underwent a total hip replacement (cemented, uncemented or hybrid) had intra-operative measurements documented of their femoral head-neck resection distance. This was compared with the measurement of the femoral prosthesis that was inserted. A telephonic survey of the patients perceived leg equality as well as a radiological measurement of their actual leg lengths on a standing AP X-ray at 6 weeks post-operatively was done. Results. Forty eight of the 56 patients (85%) reported subjectively equal leg lengths. Eight patients reported unequal leg lengths, 5 longer and 3 shorter. Of the 5 cases that reported longer leg lengths 4 had more prosthesis inserted than bone resected. The 3 shorter reported legs also had more prosthesis inserted than bone resected in 2 cases. Of the 8 patients who reported unequal leg lengths only 3 were unequal on X-ray measurement (2 longer and 1 shorter). There was good correlation between the amount of bone resected versus prosthesis inserted and the patient's subjective evaluation of leg length discrepancy, but poor correlation between subjective leg length discrepancy and objective radiological evaluation. NO DISCLOSURES

Background. Approximately half of all hip fractures are displaced intracapsular fractures. The standard treatment for these fractures is either hemiarthroplasty or total hip arthroplasty. The recent National Institute for Health and Care Excellence (NICE) guidance on hip fracture management recommends the use of ‘proven’ cemented stem arthroplasty with an Orthopaedic Device Evaluation Panel (ODEP) rating of at least 3B (97% survival at three years). The Thompsons prosthesis is currently lacking an ODEP rating despite over 50 years of clinical use, likely due to the paucity of implant survival data. Nationally, adherence to these guidelines is varied as there is debate as to which prosthesis optimises patient outcomes. Design. This study design is a multi-centre, multi-surgeon, parallel, two arm, standard-of-care pragmatic randomised controlled trial. It will be embedded within the WHiTE Comprehensive Cohort Study (ISRCTN63982700). The main analysis is a two-way equivalence comparison between Hemi-Thompson and Hemi-Exeter polished taper with Unitrax head. Secondary outcomes will include radiological leg length discrepancy measured as per Bidwai and Willett, mortality, re-operation rate and indication for re-operation, length of index hospital stay and revision at four months. This study will be supplemented by the NHFD (National Hip Fracture Database) dataset. Discussion. Evidence on the optimum choice of prosthesis for hemiarthroplasty of the hip is lacking. National guidance is currently based on expert opinion rather than empirical evidence. The incidence of hip fracture is likely to continue to increase and providing high quality evidence on the optimum treatment will improve patient outcomes and have important health economic implications. Cite this article: A. L. Sims. The World Hip Trauma Evaluation Study 3: Hemiarthroplasty Evaluation by Multicentre Investigation – WH. I. TE 3: HEMI – An Abridged Protocol. Bone Joint Res 2016;5:18–25. doi: 10.1302/2046-3758.51.2000473

We present a study done to measure the change of angle of the acetabulum or cup, due to leg length discrepancy, deformity of hip and spine on standing. In 1998 a 3-dimensional reconstruction of hip model was prepared on CAD and the change of angle of the cup was measured as Functional Acetabular Inclination Angle (FAIA) with patient standing without squaring the pelvis. The FAIA on standing was compared with angle of the cup with patient in supine position with squared pelvis. The position of the cup changed on weight bearing due to multiple issues. The results showed that one centimetre of leg lengthening changed FAIA by 3°, 10° of abduction deformity resulted in apparent lengthening of 2.87 cm and loss of lordosis anteverted the cup on loading and vice-versa. We conclude that fixed hip deformities, leg length discrepancy and spine deformities can affect the angle of cup in hip replacement surgery and may prone to dislocations, impingement and segmental wear of the cup

Aims. There is no consensus about the best method of achieving equal leg lengths at total hip arthroplasty (THA) in patients with Crowe type-IV developmental dysplasia of the hip (DDH). We reviewed our experience of a consecutive series of patients who underwent THA for this indication. Patients and Methods. We retrospectively reviewed 78 patients (86 THAs) with Crowe type-IV DDH, including 64 women and 14 men, with a minimum follow-up of two years. The mean age at the time of surgery was 52.2 years (34 to 82). We subdivided Crowe type-IV DDH into two major types according to the number of dislocated hips, and further categorised them into three groups according to the occurrence of pelvic obliquity or spinal curvature. Leg length discrepancy (LLD) and functional scores were analysed. Results. Type-I included 53 patients with unilateral dislocation, in which 25 (category A) had no pelvic obliquity or spinal deformity, 19 (category B) had pelvic obliquity with a compensated spinal curvature and nine (category C) had pelvic obliquity and decompensated spinal degenerative changes. Type-II included 25 patients with one dislocated and one dysplastic hip, in which there were eight of category A, 15 of category B and two of category C. Pre-operatively, there were significant differences between the anatomical and functional LLD in type-IB (p = 0.005) and -IC (p < 0.001), but not in type-IA, -IIA or -IIB. Post-operatively, bony LLD increased significantly in types-IB, -IC and -IIB, whereas functional LLD decreased significantly in each type except for IIA. The mean functional LLD decreased from 30.7 mm (standard deviation (. sd. ) 18.5) pre-operatively to 6.2 mm (. sd. 4.4) post-operatively and the mean anatomical LLD improved from 35.8 mm (. sd. 19.7) pre-operatively to 12.4 mm (. sd. 8.3) post-operatively. Conclusion. Pelvic and spinal changes are common in patients with Crowe type-IV DDH and need to be taken into consideration when planning THA, in order to obtain equal leg lengths post-operatively. The principal subdivisions of Crowe type-IV DDH which we describe proved effective in achieving equal leg lengths and satisfactory outcomes. Cite this article: Bone Joint J 2017;99-B:872–9

Paediatric bone sarcomas are a dual challenge for orthopaedic surgeons in terms of tumour resection and reconstruction, as it is important to minimize functional and growth problems without compromising survival rates. Cañadell’s technique consists of a Type I epiphysiolysis performed using continuous distraction by an external fixator prior to resection. It was designed to achieve a safe margin due to the ability of the physeal cartilage to be a barrier to tumour spread in some situations, avoiding the need for articular reconstruction, and preserving the growth capacity most of the times. Despite initial doubts raised in the scientific community, this technique is now widely used in many countries for the treatment of metaphyseal paediatric bone sarcomas. This annotation highlights the importance of Cañadell’s work and reviews the experience of applying it to bone sarcoma patients over the last 40 years.

Cite this article: Bone Joint J 2023;105-B(1):11–16.

Aims

Distraction osteogenesis with intramedullary lengthening devices has undergone rapid development in the past decade with implant enhancement. In this first single-centre matched-pair analysis we focus on the comparison of treatment with the PRECICE and STRYDE intramedullary lengthening devices and aim to clarify any clinical and radiological differences.

Background. While not common in the native hip, occurrences of femoral head separation from the acetabular cup during gait are well documented after total hip arthroplasty. Although the effects of this phenomenon are not well understood, we hypothesize that these atypical kinematics are due to component misalignments that yield uncharacteristic forces on the hip joint that are not present in the native hip. Objective. The objective of this study was to theoretically predict the causes of hip separation during stance phase using forward solution mathematical modelling. Methods. The model simulates the quadriceps muscles, hamstring muscles, gluteus muscles, iliopsoas group, tensor fasciae latae, and an adductor muscle group. Other soft tissues include the patellar ligament and the ischiofemoral, iliofemoral, and pubofemoral hip capsular ligaments. The model was previously validated using telemetric implants and fluoroscopic results from existing implant designs. The model is currently being used to analyze the effects that various surgical alignments have on hip separation. Specifically, this study analyzed 4 different hypothetical patients under the same 87 alignment conditions during stance phase. Alignment conditions include anatomical component alignment, intended acetabular cup medial and superior shifts, unintended cup medial and superior reaming errors, variations in cup version angles, leg length discrepancies, and femoral component offset modifications. Results. During stance phase, it was determined that acetabular cup placement had a much more substantial effect on hip separation than femoral component placement. While neither femoral offset nor leg length discrepancy showed a correlation to hip separation, both medial and superior shifting of the acetabular cup showed a positive trend with increased hip separation. Figure 1 shows a comparison of average hip separation with intended shifts in the cup (0mm, 2mm, or 5mm) plus unintended reaming errors (0mm to 10mm extra) Furthermore, larger intended shifts in cup placement yielded smaller margins of error (Figure 2). Observe in Figure 2 how an increase in the size of the blue region (intended shifting region) correlates to a decrease in size of the green region (allowable error region where hip separation will not occur). It was also determined that cup version angles have less of a defined effect on hip separation, as the relationship between angular position and hip separation varied between patients. Discussion. From our current analysis, the importance of proper alignment of the acetabular cup can be clearly seen. Overall, it has been shown that reaming errors of as low as 2 mm can yield separation magnitudes up to 2 mm (and potentially greater)

Aims

Dual-mobility acetabular components (DMCs) have improved total hip arthroplasty (THA) stability in femoral neck fractures (FNFs). In osteoarthritis, the direct anterior approach (DAA) has been promoted for improving early functional results compared with the posterolateral approach (PLA). The aim of this study was to compare these two approaches in FNF using DMC-THA.

Preoperative planning is a crucial step for total hip arthroplasty (THA), and 2D X-ray images are commonly used. The planning aims to provide the correct implant size, restore functional biomechanical conditions and avoid early complication such as dislocation, leg length discrepancy or abductors insufficiency. Limitations of 2D planning, besides the low accuracy in sizing, concerns the inability of planning the anteversion of both acetabular and femoral component on axial plane. Also, the verification of the planning intraoperatively is wholly left to qualitative measurements and the surgeon's experience. The need for having a more accurate and functional preoperative planning has been addressed using 3D models. The MyHip Planner (MHP) (Medacta International, Castel San Pietro, Switzerland), is a preoperative planning software which through artificial intelligent algorithm converts the CT scans into a 3D model that perfectly match the patient's anatomy. Then, automatic positioning of the implants is performed following the personal settings of the surgeon which will check and validate the planning, a personalized simulation of six daily activities to detect impingement of implants and bones. The MyHip Verifier (MHV) intraoperatively verifies the execution of the planning in terms of leg length and offset using two fluoroscopic images. Also, the size and cup angles can be calculated. The purpose of the present study was to validate the accuracy of the MHP [Fig 1] and MHV [Fig 2]. The dataset consisted of 13 patients who underwent primary uncemented THA. Each patient had a preoperative CT scan, intraoperative fluoroscopy, and postoperative CT scan after the surgery. The CT protocol used was low radiation (0,2 mm slicing for the pelvis, 0,5 mm for knees and ankles). The patients have been preoperatively planned used the MPH, and the accuracy of the components size prediction has been evaluated by comparing the preoperative planned values with the surgical reports. The MVH calculated the leg length and offset in terms of the difference between the preoperative and postoperative position of the femur concerning the pelvis. The accuracy of the measurements has been evaluated using postoperative CT scans. The MPH was able to predict the implanted size in 83% of the patient for the femoral stem and 96% for the acetabular component. The accuracy of the MVH in measuring the leg length was under 2 mm (1,6 ± 0,7 mm) while the offset was 2,5±1,6 mm. The cup angles were 5±1,1deg and 2,3±1,3deg for the anteversion and inclination, respectively. The average cup anteversion was 28,3°, mean cup inclination was 42,6°; femoral offset and leg length was restored in 96,5% of patients within a range of ±3 mm concerning the preoperative position. The results demonstrated the reliability of the MPH in predicting the implant size, and the accuracy of the MVH to verify the execution of the plan intraoperatively. The two software can be used in the clinical routine to improve the clinical outcome in THA. Limitations of this study are represented mainly by the small cohort of patients involved. For any figures or tables, please contact the authors directly

Introduction. There is growing evidence that patients with lumbar spine fusion are at greater risk for postoperative dislocation following total hip arthroplasty. The purpose of this study is to review one author's experience with the modified direct lateral approach in patients with prior or subsequent lumbar spine fusion and total hip arthroplasty. Methods. Our IRB approved clinical database was queried for all primary total hip arthroplasties performed by the senior author from 1/1/2004 to 12/31/2016. All were performed via a modified direct lateral approach. Of these 1902 hips (1656 patients), 59 were identified in our medical records as patients who had a prior spine fusion or a spine fusion following THA. The extent of fusion was identified and reported. Radiographs were reviewed for acetabular position (abduction and anteversion) and leg length discrepancies. Records were reviewed and patients were contacted to determine if there were dislocations. Results. Of the 59 patients with concomitant spine fusion and total hip arthroplasty, 47 had the fusion prior to THA and 12 following THA. All patients were seen in the office or contacted by phone for a mean follow up of 5.8 years (2 to 15 years)(3 deceased, 3 lost). The direct lateral approach was used in all cases and in no cases was a dual mobility, lipped liner, or constrained component used. Head size ranged from 32 to 40. There were no postoperative dislocations in any of these patients. Acetabular position was a mean 43.6 degrees abduction (range 30–50), and a mean anteversion of 23.7 degrees (range 17 – 34). Average postoperative LLD was 2.8mm long on operated side (range −2mm to + 12mm). Spine fusion extent was a mean 2.1 levels (range 1 – 9) with 15 that included the sacrum/pelvis. Discussion. As surgeons have become aware of the elevated risk of hip dislocation associated with spine fusion/stiffness, several approaches have been proposed to address this risk. Our findings suggest that using the modified direct lateral approach for primary total hip arthroplasty significantly reduces the risk of such a complication. For any tables or figures, please contact the authors directly

Aims

Temporary hemiepiphysiodesis (HED) is applied to children and adolescents to correct angular deformities (ADs) in long bones through guided growth. Traditional Blount staples or two-hole plates are mainly used for this indication. Despite precise surgical techniques and attentive postoperative follow-up, implant-associated complications are frequently described. To address these pitfalls, a flexible staple was developed to combine the advantages of the established implants. This study provides the first results of guided growth using the new implant and compares these with the established two-hole plates and Blount staples.

Aims

Accurate skeletal age and final adult height prediction methods in paediatric orthopaedics are crucial for determining optimal timing of growth-guiding interventions and minimizing complications in treatments of various conditions. This study aimed to evaluate the accuracy of final adult height predictions using the central peak height (CPH) method with long leg X-rays and four different multiplier tables.