Sacroiliac pain after total hip arthroplasty: a combined analysis of clinical data and three-dimensional imaging in standing and sitting positions.

PURPOSE: Patients frequently complain of low back pain and sacroiliac joint pain (SIP) following total hip arthroplasty (THA). We hypothesized that patients with SIP would display different pelvic incidence (PI) values between standing and relaxed sitting positions, indicative of increased motion in the sacroiliac joints. METHODS: In this retrospective case-control study, 94 patients who underwent unilateral THA and experienced SIP were compared with 94 control patients without SIP. SIP was confirmed through clinical tests and investigated using biplanar imaging in both standing and sitting positions. The key parameters analyzed included PI, sacral slope (SS), lumbar lordosis (LL), and limb length discrepancy (LLD). RESULTS: Patients without SIP showed a mean difference in PI of -1.5° (-8°-5°) between standing-to-sitting positions, whereas those with SIP showed a difference of -3.3° (-12°-0°)(P < 0.0001), indicating more motion in the sacroiliac joint during daily activities in the latter group. Patients with SIP showed smaller change in LL between standing-to-sitting positions (mean:6.3°; range:-8°-27°) compared with those without SIP (mean:9.5°; range:-12°-28°)(P = 0.006). No significant differences were noted in functional leg length between patients with (mean:7 mm; range:0-12 mm) and without SIP (mean:7 mm; range:0-11 mm)(P = 0.973). CONCLUSIONS: This study revealed significant sacroiliac joint motion in patients with SIP post-THA, as indicated by PI changes, increased posterior pelvic tilt, and reduced change in the LL. Contrary to common belief, SIP did not correlate with LLD.

The effect of intraoperative fluoroscopy on acetabular component positioning and patient anatomy restoration during posterior or posterolateral approach total hip arthroplasty: a meta-analysis.

BACKGROUND: Positioning implant components and restoring patient anatomy during total hip arthroplasty (THA) are essential for joint stability, polyethylene liner wear, and range of motion. Previous studies comparing intraoperative fluoroscopy with no fluoroscopy during the posterior or posterolateral approach have reported conflicting results. This meta-analysis evaluated if intraoperative fluoroscopy improves component positioning and femoral component position compared to no fluoroscopy during posterior or posterolateral approach total hip arthroplasty. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses standards were followed when conducting the systematic review. We searched Web of Science, Embase, PubMed, Cochrane Controlled Trials Register, Cochrane Library, Highwire, CBM, CNKI, VIP, and Wanfang database in May 2023 to identify studies involving Intraoperative fluoroscopy versus no fluoroscopy during posterior or posterolateral approach total hip arthroplasty. Finally, we identified 1133 patients (1145 hips) assessed in seven studies. RESULTS: There were no significant differences in terms of acetabular cup inclination angle (ACIA, P = 0.43), ACIA within safe zone rate (P = 0.58), acetabular cup anteversion angle (ACAA, P = 0.46); ACAA within safe zone rate (P = 0.72), Combined safe zone rate (P = 0.28), dislocation rate (P = 0.64) and infection rate (P = 0.94) between two groups. Compared with the no fluoroscopy group, the intraoperative fluoroscopy group had more operation time (P < 0.00001), less femoral component offset difference (FCOD, P = 0.03), and less LLD (P < 0.00001). CONCLUSION: Even though intraoperative fluoroscopy was not related to an improvement in cup location or dislocation incidence. Our findings demonstrate that the restoration of leg lengths and femoral offset can be significantly improved by using intraoperative fluoroscopy to supplement good surgical skills in THA. The advantages of intraoperative fluoroscopy might become more apparent for surgeons with less experience. To ascertain whether intraoperative fluoroscopy for posterior or posterolateral approach total hip arthroplasty will have clinical benefits and improve the survival of prostheses, more well-powered and well-designed long-term follow-up studies were necessary.

Mathematical explanations for knee osteotomies: "Dear engineer, how would you explain it in a simple way?"

INTRODUCTION: Knee osteotomies are effective procedures to treat different deformities and to redistribute the load at the joint level, reducing the risk of wear and, consequently, the need for invasive procedures. Particularly, knee osteotomies are effective in treating early arthritis related to knee deformities in young and active patients with high functional demands, with excellent long-term results. Precise mathematical calculations are imperative during the preoperative phase to achieve tailored and accurate corrections for each patient and avoid complications, but sometimes those formulas are challenging to comprehend and apply. METHODS: Four specific questions regarding controversial topics (planning methods, patellar height, tibial slope, and limb length variation) were formulated. An electronic search was performed on PubMed and Cochrane Library to find articles containing detailed mathematical or trigonometrical explanations. A team of orthopedic surgeons and an engineer summarized the available Literature and mathematical rules, with a final clear mathematical explanation given by the engineer. Wherever the explanation was not available in Literature, it was postulated by the same engineer. RESULTS: After the exclusion process, five studies were analyzed. For three questions, no studies were found that provided mathematical analyses or explanations. Through independent calculations, it was demonstrated why Dugdale's method underestimates the correction angle compared to Miniaci's method, and it was shown that the variation in patellar height after osteotomy can be predicted using simple formulas. The five included studies examine postoperative variations in limb length and tibial slope, providing formulas applicable in preoperative planning. New formulas were independently computed, using the planned correction angle and preoperatively obtained measurements to predict the studied variations. CONCLUSIONS: There is a strict connection among surgery, planning, and mathematics formulas in knee osteotomies. The aim of this study was to analyze the current literature and provide mathematical and trigonometric explanations to important controversial topics in knee osteotomies. Simple and easy applicable formulas are provided to enhance the accuracy and outcomes of this surgical procedure.

Does the use of intraoperative measurement reduce limb length discrepancies after total hip arthroplasty?

PURPOSE: Postoperative limb length discrepancy (LLD) is a common complication of total hip arthroplasty, and several methods exist to prevent LLD, but each has its benefits and drawbacks. The study investigates the application of intraoperative lower limb length measurement in preventing postoperative LLD. METHODS: This study retrospectively analyzed 70 patients who underwent total hip arthroplasty from October 2018 to July 2022. The length of the lower limb on the operated side was measured intraoperatively using a sterilized paper ruler after the fitting of the trial mould and compared with the healthy side. Then the prosthesis size, depth and neck length were adjusted accordingly. RESULTS: The absolute value of postoperative LLD was found to be 6.68 ± 4.48 mm, of which 53 cases (75.7%) were less than or equal to 10 mm, while 30 patients (42.9%) were less than or equal to 5 mm. CONCLUSION: The use of intraoperative measurement is effective in reducing LLD after total hip arthroplasty.

Percutaneous epiphysiodesis using transphyseal screws (PETS) versus tension-band plating (TBP): comparative study of outcomes for correcting limb length discrepancy.

OBJECTIVES: The best effective treatment strategy for limb length discrepancy (LLD) is still being debated. The goal of this study was to compare the efficacy and results of tension-band plating (TBP) and percutaneous epiphysiodesis using transphyseal screws (PETS) for LLD correction. METHODS: From June 2008 to January 2019, children who had lower extremity epiphysiodesis with either TBP or PETS were reviewed retrospectively. At the conclusion of treatment, LLD, angular deformity, and complications were reviewed. The t-test or Wilcoxon rank sum test was used to compare continuous variables. Categorical variables were evaluated using Fisher's exact test or χ2 test. RESULTS: A total of 32 epiphysiodeses with TBP (14 patients, 24 femur/tibias) or PETS (13 patients, 23 femur/tibias) were compared. TBPs were conducted while the patients were younger (11.0 vs. 13.1 years, p = 0.005). The treatment durations were similar in both groups (TBP: 23.5 months vs. PETS: 24 months, p = 0.132). PETS had significantly shorter operative time (p = 0.047), length of hospital stay (p = 0.014), and time to return to full activity (p = 0.043). LLD in the TBP group reduced from 2.64 to 1.38 cm (p = 0.005), while in the PETS group it decreased from 2.76 to 1.08 cm (p = 0.001). During treatment, the rate of LLD correction was 0.49 ± 0.9 cm/year for limbs treated with TBP and 1.0 ± 1.1 cm/year for limbs treated with PETS (p = 0.185). At the end of treatment, 8 TBP cases (47%) and 9 PETS cases (60%) had achieved LLD ≤ 2 cm (p = 0.502), and at the most recent follow-up, this had grown to 11 (65%) in the TBP group and 12 (80%) in the PETS group. There were no significant differences in the total number of complications between groups (p > 0.05). Revision surgery was required in 11 TBP and 3 PETS limbs due to persistent LLD or angular deformity (AD) (p = 0.016). Logistic regression did not reveal any significant association between TBP and the rate of complication or revision surgery. CONCLUSION: PETS and TBP are both effective methods for limb length equalization. PETS, on the other hand, was linked to a shorter operative time, a shorter hospital stay, a faster recovery to pre-operative function, and a lower complication rate. The rate of revision surgery due to persistent LLD or AD was higher in TBP. We advise surgeons against utilizing TBP to correct LLD. LEVEL OF EVIDENCE: III.

Three-dimensional printed customized uncemented unipolar prosthesis combined with ligament reconstruction for tumorous defect of the distal femur in children.

BACKGROUND: Hemiarthroplasty following tumor resection of the distal femur in children provides a chance to preserve the proximal tibial physis for limb elongation. Based on three-dimensional (3D) printing technology, the uncemented unipolar prosthesis with joint stability reinforced structures (JSRSs) was custom-designed for our cases. This study aimed to describe the design and assess the short-term outcomes of this refined prosthetic hemiarthroplasty. METHODS: Seven patients (four females and three males) received 3D-printed customized uncemented unipolar prosthesis for hemiarthroplasty after removal of the distal femur, from September 2019 to October 2020 at our Orthopedics department. The limb function, growth of the preserved proximal tibial physis, joint stability, and limb length discrepancy (LLD) were assessed. Complications were recorded. RESULTS: Six patients survived with no evidence of metastasis or local recurrence at the last follow-up, and one patient died of lung metastasis at 19 months postoperatively. Follow-up ranged from 19 to 32 months, with an average of 26 months. Elongation of the tibia was observed in all cases. At the last follow-up, four patients exhibited equal growth length compared with the healthy contralateral tibia. LLD ranged from 0.8 to 1.6 cm with a mean of 1.3 cm. The average knee range of motion was 95.3° of flexion and 4.5° of extension. All patients achieved satisfactory postoperative limb function with a mean MSTS score of 25.8. The results of the drawer, Lachman, and pivot shift tests were negative in all patients. During follow-up, painless joint space narrowing was observed in two patients. The screw for ligament fixation loosened in one of the seven patients at 17 months postoperatively. No subluxation of the joint, angular deformity, or breakage of the implant was detected in the remaining patients. CONCLUSIONS: 3D-printed customized uncemented unipolar prosthesis with JSRS would be a good choice for reconstructing tumorous defect in the distal femur in children.

Bifocal femoral lengthening assisted by preoperative 3-dimensional design in the restoration of posttraumatic limb length discrepancy.

BACKGROUND: To assess the clinical outcomes of preoperative three-dimensional planning followed by bifocal femoral lengthening in the treatment of posttraumatic limb length discrepancy (LLD). METHODS: A total of 8 eligible patients with posttraumatic femoral LLD > 6 cm were admitted to our institution from January 2015 to January 2018 and treated by bifocal femoral lengthening with the assistance of 3-dimensional imaging technology. The following data were collected: detailed demographic information, the amount of lengthening, external fixation time (EFT), external fixation index (EFI), postoperative bone and functional outcomes, and complications in the follow-up period. RESULTS: All included patients were successfully followed up for in an average of 55.4 ± 6.7 months after removal of the external fixator. There were six males and two females with an average age of 38.4 ± 12.2 years. The mean preoperative LLD was 69.2 ± 6.2 mm. The mean lengthening amount was 67.5 ± 6.9 mm. The mean EFT was 180.1 ± 20.2 days. The EFI was 26.73 ± 1.36 days/cm on average. All patients achieved satisfactory postoperative bone and functional outcomes. No major complications such as nerve or vascular injury were observed. CONCLUSIONS: Bifocal femoral lengthening with preoperative three-dimensional design provided precise surgical guidance and resulted in satisfactory postoperative outcomes, demonstrating that it is an effective treatment for posttraumatic femoral LLD.

Development of the gait outcomes assessment list for lower-limb differences (GOAL-LD) questionnaire: a child and parent reported outcome measure.

BACKGROUND: To develop a priority-based patient/parent reported outcome measure for children with lower-limb differences (LD) by adapting the Gait Outcomes Assessment List (GOAL) questionnaire. METHODS: Guided by a conceptual framework of patient priorities, the GOAL questionnaire was iteratively modified and its sensibility evaluated by field-testing it on children with LD, and their parents. Cognitive interviews were conducted with a subgroup of these children, and an e-survey administered to a multidisciplinary group of health care professionals with expertise in paediatric LD. Findings were integrated to create the final version of the GOAL-LD. RESULTS: Twenty-five children (9-18 years), 20 parents, and 31 healthcare professionals evaluated the content and sensibility of the GOAL, with an emphasis on the relevance and importance of the items to patients' health related quality of life (HRQL). This resulted in the retention of 26 of the original 50 items, elimination of 12, modification of 12, and addition of seven new items. The new 45-item GOAL-LD questionnaire was shown to be sensible, and its content deemed important. CONCLUSIONS: The GOAL-LD questionnaire has a high level of face and content validity, and sensibility. It comprehensively captures the HRQL goals and outcomes that matter to children with LD and their parents. Following further psychometric evaluation, the GOAL-LD may serve as a much needed patient and parent reported outcome measure for this population.

Anatomical landmark localization via convolutional neural networks for limb-length discrepancy measurements.

BACKGROUND: Measurement of limb-length discrepancy (LLD) from a radiograph is a cognitively simple but time-consuming task. OBJECTIVE: To develop a convolutional neural network (CNN) to localize anatomical landmarks from full-length lower-extremity radiographs in predicting LLD. MATERIALS AND METHODS: The author searched a hospital's image database to identify studies performed between Feb. 1, 2016, and Sept. 30, 2019. Inclusion criteria were: (1) patients ≤21 years old, (2) study indication of LLD, (3) full-length lower-extremity anteroposterior radiographs performed on the EOS system, and (4) imaging field-of-view that included entire bilateral femurs and tibias. The six requisite ground truth anatomical landmarks for measuring LLD from each radiograph - bilateral top of femoral heads, medial femoral condyles, and center of tibial plafonds - were manually labeled by a pediatric radiologist. For each landmark, a two-dimensional heatmap was generated to encode the pseudo-probability of a landmark being at a particular spatial location. A CNN was developed that regressed across a collection of these heatmaps for landmark localization and bone length predictions. RESULTS: The study cohort consisted of 504 full-length lower-extremity radiographs from 359 patients with wide ranging skeletal deformities and in situ hardware. Evaluation of this CNN showed that the mean point-error for the predicted top of femoral head, medial femoral condyle, and center of tibial plafond were 0.37 cm, 0.39 cm and 0.42 cm, respectively. The mean absolute error for the predicted femoral, tibial and limb lengths, and LLD were 0.33 cm, 0.30 cm, 0.30 cm, and 0.36 cm, respectively. Predicted bone lengths correlated strongly with ground truth. CONCLUSION: This prototype CNN delivered promising results in predicting bone lengths from full-length lower-extremity radiographs and offers the potential use of a computer algorithm to predict LLD.

Anatomic all-epiphyseal ACL reconstruction with "inside-out" femoral tunnel placement in immature patients yields high return to sport rates and functional outcome scores a minimum of 24 months after reconstruction.

PURPOSE: To understand if anatomic physeal-sparing ACL reconstruction in the immature host preserves range of motion, permits a return to sports, and avoids limb length discrepancy and accelerated intra-articular degeneration with a cross-sectional radiographic, physical examination and patient-reported outcomes analysis. METHODS: A cross-sectional recall study included 38 patients aged 7-15 who underwent all-epiphyseal ACL reconstruction with hamstring allograft performed by a single surgeon at a large academic medical center. All-epiphyseal reconstructions were performed using a modified Anderson physeal-sparing technique, with the femoral tunnel placed using an "inside-out" technique. Assessments consisted of a physical exam, long leg cassette radiographs, KT-1000 measurements, subjective patient metrics, and magnetic resonance imaging. RESULTS: Thirty-eight (56.7%) of 66 eligible patients returned for in-person clinical and radiographic exams. Patients were 11.4 ± 1.8 years at the time of surgery. Five patients were females (13.2%). Mean follow-up was 5.5 ± 2.4 years. ACL re-injuries occurred in four patients (10.5%), all of whom underwent revision reconstructions. Thirty-three of the remaining 34 (97.1%) patients returned to sports following their reconstruction, and 24 (70.6%) returned to their baseline level of competition. Mean limb length discrepancy (LLD) was 0.2 ± 1.4 cm. Nine patients had an LLD of > 1 cm (26.5%), which occurred at an equivalent age as those with < 1 cm LLD (10.8 ± 2.0 vs. 11.7 ± 1.7, n.s.). Pre-operative Marx scores (13.1 ± 3.5) were not significantly different from post-operative values (12.3 ± 5.1, n.s.). Patients who required ACL revisions had significantly lower Marx scores than those with intact primary grafts (8.3 ± 7.1 vs. 13.4 ± 4.5, p = 0.047). Cohort mean International Knee Documentation Committee (IKDC) score was 89.7 ± 12.7. CONCLUSION: Anatomic all-epiphyseal anatomic ACL reconstruction appears to be useful in patients with significant projected remaining growth, with good return-to-sport outcomes and minimal risk of clinically significant physeal complications. However, given the limited patient recall possible in the present study, further large sample size, high-quality works are necessary to validate our findings. LEVEL OF EVIDENCE: Level IV.

Evolving Patient Perception of Limb Length Discrepancy Following Total Hip Arthroplasty.

BACKGROUND: Limb length discrepancy (LLD) is a known complication of total hip arthroplasty (THA), leading to decreased patient function and satisfaction. It remains unknown how a patient's perception of LLD evolves over time. The aim of this study is to evaluate the relationship between measured and perceived LLD, and to assess whether perceived LLD resolved with time in most patients. METHODS: This study retrospectively reviewed radiographs of 140 consecutive patients undergoing primary THA by a single surgeon via a direct anterior approach, calculating postoperative change in limb length (ΔL). Patient perceptions of LLD were recorded at standard postoperative visit intervals. A P-value of .05 was used to determine statistical significance. RESULTS: Of 130 patients (mean ΔL = +7.9 mm), 22 patients endorsed perceived postoperative LLD and the remainder were asymptomatic (mean ΔL +11.1 mm vs +7.3 mm, P = .03). Seventeen patients reported mild symptoms and 5 reported severe symptoms (mean ΔL +10.2 mm vs +13.8 mm, P = .4). After 1 year, 45% (10) patients reported complete resolution of perceived LLD (mean follow-up 364 days), 18% (4) reported notable improvement, and 36% (8) reported no improvement. Four excluded patients endorsed perceived LLD (2 mild, 2 severe), which resolved after contralateral THA. CONCLUSION: This study noted a correlation between increasing postoperative ΔL and perceived LLD. A majority of patients (63%) experienced either improvement or full resolution of symptoms during the follow-up period. This data may have a role in reassuring the orthopedic surgeon and the patient regarding the natural course of postoperative LLD. Further investigation is needed to help identify risk factors for persistent LLD. LEVEL OF EVIDENCE: Level III (Prognostic).

Limb Length Discrepancy in Total Hip Arthroplasty: Is the Lesser Trochanter a Reliable Measure of Leg Length?

BACKGROUND: Limb length discrepancy (LLD) after total hip arthroplasty may affect clinical outcomes and patient satisfaction. Preoperative LLD estimates on anteroposterior pelvic radiographs fail to account for anatomical limb variation distal to the femoral reference points. The objective of this study is to determine how variations in lower limb skeletal lengths contribute to true LLD. METHODS: Full-length standing anteroposterior radiographs were used to measure bilateral leg length, femoral length, and tibial length. Leg length was evaluated using 2 different proximal reference points: the center of the femoral head (COH) and the lesser trochanter (LT). Mean side-to-side discrepancy (MD) and percentage asymmetry (%AS) for each measurement were evaluated in the overall cohort and when stratified by patient demographic variables. RESULTS: One hundred patients were included with an average age of 62.9 ± 11.2 years. Average femoral length was 434.0 ± 39.8 mm (MD 4.3 ± 3.5 mm) and tibial length was 379.9 ± 34.6 mm (MD 5.9 ± 12.7 mm). Average COH-talus was 817.5 ± 73.2 mm (MD 6.4 ± 5.1 mm). Average LT-talus was 760.5 ± 77.6 mm (MD 5.8 ± 5.1 mm). Absolute asymmetry >10 mm was detected in 16% of patients for COH-talus and 15% for LT-talus, while %AS >1.5% was detected in 13% of patients for COH-talus and 18% for LT-talus. Female gender was associated with increased femoral length %AS (P = .037). CONCLUSION: Approximately 1 in 6 patients have an LLD of >10 mm when measured from either the LT or COH. Surgeons using either of these common femoral reference points to estimate LLD on pelvic radiographs should consider these findings when planning for hip reconstruction. LEVEL OF EVIDENCE: Level III.

The More the Merrier: Integrating Multiple Models of Skeletal Maturity Improves the Accuracy of Growth Prediction.

BACKGROUND: Multiple systems using radiographic skeletal markers to measure development have been described, including the Greulich and Pyle Atlas (GP), the Fels Method (Fels), and the Sanders Hand Classification (Sanders). The purpose of this study was to quantitatively assess whether the integration of skeletal maturity assessment methods and demographic variables improves the accuracy of pediatric growth predictions over the use of skeletal markers or chronologic age alone. METHODS: The Brush Inquiry contains prospectively collected longitudinal data on children who lived in Cleveland, Ohio between 1926 and 1942. A total of 16 boys and 29 girls were selected for study. All had age, height, and an anteroposterior radiograph of the hand at each of 3 visits. Those visits occurred at 85%, 90%, and 95% of final height. We determined the growth completed at each visit by dividing the height observed by the final height at skeletal maturity. Boys and girls were analyzed separately using chronologic age, height, GP, Fels, and Sanders. The residual difference between the height predicted and actual height, as well as the SD of the prediction error of the cohort at each time point was calculated. To account for multiple visits from each subject, all linear models were produced using the generalized estimating equations (GEEs) procedure. RESULTS: For boys, age, GP, and Fels performed similarly in predicting growth remaining at all 3 time points. For girls, age, GP, and Fels performed similarly in predicting growth remaining at the 85% and 95% time points; however, the Fels Method demonstrated improved performance at the 90% time point compared with chronologic age (P = 0.0076) and GP alone (P = 0.0155). For both boys and girls, the most accurate multivariate GEE model with the lowest SD of prediction error integrated Fels, age, GP, Sanders, and height. CONCLUSIONS: The most accurate multivariate GEE model of growth prediction for both boys and girls integrated Fels, age, GP, Sanders, and height. When calculating the amount of growth remaining, it is prudent to integrate multiple systems for greater predictive accuracy. LEVEL OF EVIDENCE: Level III.

Epiphysiodesis for the treatment of tall stature and leg length discrepancy.

Painful orthopedic conditions associated with extreme tall stature and leg length discrepancy (LLD) include back pain and adopting bad posture. After failure of conservative treatment options, blocking of the growth plates (epiphysiodesis) around the knee emerged as gold standard in patients with tall stature and LLD in the growing skeleton. Surgical planning includes growth prediction and evaluation of bone age. Since growth prediction is associated with a certain potential error, adequate planning and timing of epiphysiodesis are the key for success of the treatment. LLD corrections up to 5 cm can be achieved, and predicted extreme tall stature can be limited. Percutaneous epiphysiodesis techniques are minimally invasive, safe and efficient methods with low complication rates. In general, a multidisciplinary approach should be pursued when treating children and adolescents with tall stature.

The King's Sliding Hindfoot Osteotomy for the Treatment of Talus Body Defects-Results of a New Technique in Tibiotalocalcaneal Arthrodesis.

Bone loss after avascular necrosis of the talus secondary to acute traumatic or chronic pathologies often requires surgical reconstruction. This study reports the early results of a sliding oblique hindfoot osteotomy for salvage procedures combined with tibiotalar arthrodesis to achieve a well-aligned, painless, plantigrade foot. All patients presenting to our institution with severe talus body defects requiring corrective surgery between January 2016 and August 2020 were included. An oblique osteotomy of the diseased talus was performed to correct anterior talus subluxation and prevent excessive loss of height at the tibiotalar apposition and to correct varus-valgus deformity. A retrograde hindfoot nail was used for intramedullary tibiotalocalcaneal arthrodesis. Patients were prospectively followed. Primary outcomes included assessment of mobility and union at 6 months. Secondary outcomes included 30-day postoperative complications, patient satisfaction and change in American Orthopaedic Foot & Ankle Society (AOFAS) score at 1-year postoperation. Nine patients underwent this procedure with a mean follow-up of 18 months (4-36 months). Average age was 66 (58-81) years. Mean body mass index was 33.7 (22-38) kg/m2. All patients went on to fusion and were ambulating at 6 months (n = 8). At 1 year, the mean improvement in AOFAS was 28.9 points (p < .05) (n = 7) and all patients were satisfied with the outcome of their treatment. This technique represents an alternative to conventional hindfoot salvage techniques showing predictable outcomes in complex hindfoot deformity with talar body collapse and anterior subluxation. Further quantitative studies are needed to define if this technique minimizes limb shortening/limb-length discrepancies when compared to traditional horizontal cuts.

Limb lengthening for deformities in Ollier's disease: a systematic review.

BACKGROUND: The management of limb deformity, shortening, and bone defects in treatment of Ollier's disease is a major challenge. This study aims to summarize and compare the different surgical treatments, and to evaluate the outcome and possible prognostic factors of leg lengthening in these patients. MATERIALS AND METHODS: A systematic review of the literature from 1993 to 2017 was performed. Nineteen articles were found including a total of 121 patients with limb deformities because of Ollier's disease. The mean patients' age at the time of first surgery was 12 years. A total of 272 segments were surgically treated (14 segments in the upper limbs) with variable techniques including osteotomies and external fixation, intramedullary nails, as well as epiphysiodesis and lengthening over nail. We studied the bone healing index (BHI), distraction index (DI), distraction time, gained length, total treatment time, and complications. RESULTS: Available implants and techniques allowed correction of patients' deformities (lengthening and correction of angular defects) in most cases. External fixators, circular or monolateral frames were the most commonly used technique. The Ilizarov external fixator was the most commonly used frame (196 segments). The BHI was significantly better when the external fixation was combined with intramedullary nails. Epiphysiodesis was most likely to be more associated with the past than to the present. Joint stiffness, infection, early consolidation, pathological fracture, deformity recurrence, delayed union, non-union, neurapraxia, and overlengthening were the reported complications with an overall rate of 27.9%. CONCLUSIONS: There is no consensus for the optimal surgical technique and implants for correction of limbs deformities in patients with Ollier's disease. External fixators most commonly circular are the most commonly used implants; however, complications do occur.

Limb length discrepancy after total knee arthroplasty may contribute to suboptimal functional results.

PURPOSE: Limb length discrepancy (LLD) has been related to inferior outcomes after total hip arthroplasty (THA), but few studies have dealt with the LLD in primary total knee arthroplasty (TKA). The aims of the study were to examine the incidence of LLD after TKA and how it can influence in the outcomes scores. METHODS: We analysed preoperative, postoperative and changes in LLD in 460 patients who underwent a unilateral primary TKA. The measurements were done on digital full leg radiographs preoperatively and 6 months after surgery. The hip-knee-ankle (HKA) angle was also measured on these radiographs. Patients were evaluated with the Knee Society Score (KSS) preoperatively and 12 months after surgery. RESULTS: The average LLD was 1.1 mm in the preoperative period and changed to -0.8 mm in the postoperative (the 1.9 mm lengthening of the operated limb was statistically significant (p < 0.001)). LLD increase was correlated with preoperative HKA angle and with HKA angle changes. Only 8.3% of the patients had significant postoperative LLD (≥ 10 mm), but they had a significant worse function outcome in the KSS one year after surgery than patients with negligible postoperative LLD (< 10 mm) (76.7 vs 82.3; p = 0.02). CONCLUSIONS: Unlike THA surgery, significant LLD is not frequent after TKA surgery, but the functional results of the surgery can be suboptimal when it is present.

External fixation-assisted reduction for the treatment of neglected hip dislocations with limb length discrepancy: a retrospective study of 13 cases.

BACKGROUND: The purpose of this study was to evaluate a new method for treating neglected hip dislocation with limb length discrepancy by using external fixation-assisted pre-reduction. METHODS: Thirteen patients admitted between January 2010 to February 2018 with a mean duration from injury to surgery of 5.0 ± 2.1 months and an average preoperative leg-length discrepancy of 7.7 ± 2.3 cm were enrolled in this study. The dislocation and associated acetabular fracture type, clinical outcomes and residual limb length discrepancy were evaluated. RESULTS: All patients had posterior dislocations, and nine patients presented with acetabular fractures and were followed-up for at least 12 months. The average traction duration of external fixators was 28.8 ± 8.0 days and all patients received second-stage open reduction and internal fixation. Six patients showed residual limb length discrepancy within 2 cm. Patients showed significant improvement in hip function and pain relief. Complications including avascular femoral head necrosis and osteoarthritis occurred in three patients. CONCLUSION: Effective correction of limb length discrepancy and improved function were observed in patients with neglected hip dislocations and limb equality using traction by external fixation combined with second-stage open reduction. Further follow-up is required to determine long-term outcomes.

Calculation method to predict postoperative limb length in patients undergoing THA following developmental dysplasia of hips.

BACKGROUND: Limb length discrepancy (LLD) is one of the main cause of dissatisfaction after total hip arthroplasty (THA). The teardrop-lesser trochanter method can accurately predict and analyze LLD for healthy people. However, for patients with preoperative LLD, no method for predicting postoperative LLD is currently available, and these patients are highly susceptible to more severe LLD after THA. Accordingly, this study proposed a calculation method to predict postoperative limb length for these patients. METHODS: Eighty patients who underwent THA between May 2016 and October 2018 due to unilateral developmental dysplasia of the hip (DDH) were evaluated. Relevant parameters were measured from radiographs of full-length lower limbs, e.g. the distance between the rotation center of the hip and the midpoint of the tibial plafond and the distance between the point which was marked at the same height as the lesser trochanter on the anatomical long axis of the femur and the midpoint of the tibial plafond. Then, a mathematical model was established by simplifying the structure from the hip to the ankle. The relationship between the placement position of the prosthesis and the LLD value was calculated by Law of Sines and Iterative Calculation. RESULTS: The preoperatively predicted LLD values and the postoperatively measured LLD values were compared, yielding a mean absolute difference of 3.7 (range, 0.1 to 8.6) mm. The intraclass correlation coefficient (ICC) of the two parameters exhibited strong reliability (ICC = 0.911, 95%CI, 0.795 to 0.955). The Bland-Altman plot also showed good conformity between the two parameters. CONCLUSIONS: The proposed calculation method effectively predicted the postoperative LLD using preoperative parameters. Despite the complexity of the method, it can go a long way towards reducing the occurrence of severe postoperative LLD in DDH-THA.

Long-Term Results of Cementless Total Hip Arthroplasty for Patients With High Hip Dislocation After Childhood Pyogenic Infection.

BACKGROUND: The purpose of this study is to analyze the 10-year outcomes of cementless, modular total hip arthroplasty (THA) in adult patients who had high dislocation secondary to childhood pyogenic arthritis. METHODS: We retrospectively followed 56 consecutive patients who underwent cementless, modular THA for the late sequelae of childhood septic arthritis of the hip from 2001 to 2011. There were 23 men and 33 women with a mean age of 47 years (24 to 68). Of the 56 hips, 25 were classified as Crowe type III and 31 as type IV. Mean follow-up was 10.7 years. RESULTS: One hip with a quiescent period of 23 years had recurrence of infection. Revision surgery was performed in 2 patients because of loosening and breakage of femoral stem and new infection with no correlation with childhood sepsis, respectively. The mean Harris hip scores improved from 44.2 points preoperatively to 87.5 points at final follow-up. Similarly, the Hip dysfunction and Osteoarthritis Outcome Score and hip pain also significantly improved at the latest follow-up. The mean acetabular cup abduction was 40.8° and the mean anteversion 27.8°, respectively. There were 5 cases of transient nerve palsy and 5 cases of intraoperative fracture. CONCLUSION: THA can reliably restore the abnormal anatomy and provide good results in these young and active patients who had high hip dislocation secondary to childhood pyogenic arthritis with a relatively high incidence of complications. However, these complications can be treated.