Effect of accelerated postoperative rehabilitation after tibial tubercle distalisation: A randomised controlled trial protocol.

Patella alta is a clinical condition where the patella is positioned too proximal in relation to the femoral trochlea. Such an abnormality may cause patellar instability and predispose to recurrent patellofemoral dislocations and patellofemoral pain. There are no conclusive guidelines for determining a threshold for too high positioned patella, as several different methods have been described to measure patellar height. As a surgical solution, distalising tibial tubercle osteotomy has been described to correct excessive patellar height. In the early phase of the distalising tibial tubercle osteotomy postoperative protocol, weightbearing and knee flexion are limited with a brace commonly for 4-8 weeks to avoid potential implant failure leading to displacement of the osteotomy or non-union. The potential risks for adverse effects associated with the limitation rehabilitation protocol include a delay in regaining knee range of motion, stiffness and muscle weakness. As a result, recovery from surgery is delayed and may lead to additional procedures and long-term morbidity in knee function. This is a prospective, randomised, controlled, single-blinded, single centre trial comparing a novel accelerated rehabilitation protocol with the traditional, motion restricting rehabilitation protocol. All skeletally mature patients aged 35 years and younger, referred to as the distalising tibial tubercle osteotomy procedure group, are eligible for inclusion in the study. Patients will be randomised to either the fast rehabilitation group or the traditional rehabilitation group. Patients with patellar instability will be additionally treated with medial patellofemoral ligament reconstruction. The hypothesis of the trial is that the novel accelerated rehabilitation protocol will lead to faster recovery and improved functional outcome at 6, 12 and 24 weeks compared with the conservative rehabilitation protocol. A secondary hypothesis is that the complication rate will be similar in both groups. The study will document short-term recovery and the planned follow-up will be 3 years. After the 1-year follow-up, the trial results will be disseminated in a major peer-reviewed orthopaedic publication. Protocol version 3.6, date 28/11/2023.

A high precision laser scanning system for measuring shape and volume of transtibial amputee residual limbs: Design and validation.

Changes in limb volume and shape among transtibial amputees affects socket fit and comfort. The ability to accurately measure residual limb volume and shape and relate it to comfort could contribute to advances in socket design and overall care. This work designed and validated a novel 3D laser scanner that measures the volume and shape of residual limbs. The system was designed to provide accurate and repeatable scans, minimize scan duration, and account for limb motion during scans. The scanner was first validated using a cylindrical body with a known shape. Mean volumetric errors of 0.17% were found under static conditions, corresponding to a radial spatial resolution of 0.1 mm. Limb scans were also performed on a transtibial amputee and yielded a standard deviation of 8.1 ml (0.7%) across five scans, and a 46 ml (4%) change in limb volume when the socket was doffed after 15 minutes of standing.

Lateral Tibial Plateau Reconstruction Using Tricortical Iliac Crest Autograft as the Weight-Bearing Surface.

VIDEO AVAILABLE AT: https://ota.org/education/ota-online-resources/video-library-procedures-techniques/lateral-tibial-plateau.

Extra-articular Osteotomy for the Management of Intra-articular Tibial Plateau Valgus Malunion.

OBJECTIVES: To report a case series of extra-articular osteotomies for the management of intra-articular tibial plateau malunions and to assess the ability to correct deformity and improve knee range of motion (ROM). METHODS: . DESIGN: Retrospective case series. SETTING: Academic, tertiary, referral center. PATIENT SELECTION CRITERIA: Adult patients with tibial plateau fracture malunion treated with extra-articular osteotomy of the femur and/or tibia between 2014 and 2023. OUTCOME MEASURES AND COMPARISON: Mechanical axis deviation (MAD), medial proximal tibia angle (MPTA), lateral distal femoral angle (LDFA), and posterior proximal tibia angle (PPTA) correction; knee ROM; and time to weight bearing. RESULTS: There were 7 patients included, 6 (85.7%) were female and 1 (14.3%) were male. The median age was 43.5 years (IQR 38.5-51, range 32-62). Four (57.1%) patients were treated with a high tibial osteotomy (HTO), and 3 (42.9%) patients were treated with an HTO and distal femoral osteotomy. One patient had concomitant supramalleolar osteotomy with HTO to address distal tibia procurvatum and valgus. Four were treated with hexapod frames, and 3 were treated with plates and screws. Median follow-up was 22.5 months (IQR 10.5-107 months, range 7-148 months). Surgical intervention corrected median radiographic measures of valgus malalignment preoperatively relative to postoperative values. This included MAD (42.5 mm-0 mm), valgus angle (12.5 degrees-1.5 degrees), MPTA (95 degrees-88.0°), and LDFA (86.0°-87.3 degrees). Surgical intervention increased maximal knee range of motion preoperatively to postoperatively. Median time to full weight bearing was 81.5 days (IQR 46-57 days, range 41-184 days). Two patients were converted to total knee arthroplasty after 5 and 10 years following HTO with hexapod frame. CONCLUSIONS: Extra-articular osteotomy is an effective treatment for addressing intra-articular malunion after tibia plateau fractures. It is effective in correcting the MAD, valgus deformity, MPTA, LDFA, PPTA, and improving knee ROM (measured through knee extension and flexion). LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The Addition of Hydroxyapatite Nanoparticles on Implant Surfaces Modified by Zirconia Blasting and Acid Etching to Enhance Peri-Implant Bone Healing.

This study investigated the impact of adding hydroxyapatite nanoparticles to implant surfaces treated with zirconia blasting and acid etching (ZiHa), focusing on structural changes and bone healing parameters in low-density bone sites. The topographical characterization of titanium discs with a ZiHa surface and a commercially modified zirconia-blasted and acid-etched surface (Zi) was performed using scanning electron microscopy, profilometry, and surface-free energy. For the in vivo assessment, 22 female rats were ovariectomized and kept for 90 days, after which one implant from each group was randomly placed in each tibial metaphysis of the animals. Histological and immunohistochemical analyses were performed at 14 and 28 days postoperatively (decalcified lab processing), reverse torque testing was performed at 28 days, and histometry from calcified lab processing was performed at 60 days The group ZiHa promoted changes in surface morphology, forming evenly distributed pores. For bone healing, ZiHa showed a greater reverse torque, newly formed bone area, and bone/implant contact values compared to group Zi (p < 0.05; t-test). Qualitative histological and immunohistochemical analyses showed higher features of bone maturation for ZiHa on days 14 and 28. This preclinical study demonstrated that adding hydroxyapatite to zirconia-blasted and acid-etched surfaces enhanced peri-implant bone healing in ovariectomized rats. These findings support the potential for improving osseointegration of dental implants, especially in patients with compromised bone metabolism.

Development and clinical validation of a deep learning-based knee CT image segmentation method for robotic-assisted total knee arthroplasty.

BACKGROUND: This study aimed to develop a novel deep convolutional neural network called Dual-path Double Attention Transformer (DDA-Transformer) designed to achieve precise and fast knee joint CT image segmentation and to validate it in robotic-assisted total knee arthroplasty (TKA). METHODS: The femoral, tibial, patellar, and fibular segmentation performance and speed were evaluated and the accuracy of component sizing, bone resection and alignment of the robotic-assisted TKA system constructed using this deep learning network was clinically validated. RESULTS: Overall, DDA-Transformer outperformed six other networks in terms of the Dice coefficient, intersection over union, average surface distance, and Hausdorff distance. DDA-Transformer exhibited significantly faster segmentation speeds than nnUnet, TransUnet and 3D-Unet (p < 0.01). Furthermore, the robotic-assisted TKA system outperforms the manual group in surgical accuracy. CONCLUSIONS: DDA-Transformer exhibited significantly improved accuracy and robustness in knee joint segmentation, and this convenient and stable knee joint CT image segmentation network significantly improved the accuracy of the TKA procedure.

Conventional vs. endoscopic-assisted curettage of benign bone tumours. An experimental study.

BACKGROUND: This experimental study aimed at directly comparing conventional and endoscopic-assisted curettage towards (1) amount of residual tumour tissue (RTT) and (2) differences between techniques regarding surgical time and surgeons' experience level. METHODS: Three orthopaedic surgeons (trainee, consultant, senior consultant) performed both conventional (4x each) and endoscopic-assisted curettages (4x each) on specifically prepared cortical-soft cancellous femur and tibia sawbone models. "Tumours" consisted of radio-opaque polyurethane-based foam injected into prepared holes. Pre- and postinterventional CT-scans were carried out and RTT assessed on CT-scans. For statistical analyses, percentage of RTT in relation to total lesion's volume was used. T-tests, Wilcoxon rank-sum tests, and Kruskal-Wallis tests were applied to assess differences between surgeons and surgical techniques regarding RTT and timing. RESULTS: Median overall RTT was 1% (IQR 1 - 4%). Endoscopic-assisted curettage was associated with lower amount of RTT (median, 1%, IQR 0 - 5%) compared to conventional curettage (median, 4%, IQR 0 - 15%, p = 0.024). Mean surgical time was prolonged with endoscopic-assisted (9.2 ± 2.9 min) versus conventional curettage (5.9 ± 2.0 min; p = 0.004). No significant difference in RTT amount (p = 0.571) or curetting time (p = 0.251) depending on surgeons' experience level was found. CONCLUSIONS: Endoscopic-assisted curettage appears superior to conventional curettage regarding complete tissue removal, yet at expenses of prolonged curetting time. In clinical practice, this procedure may be reserved for cases at high risk of recurrence (e.g. anatomy, histology).

Improving the identification of bone-specific physical activity using wrist-worn accelerometry: A cross-sectional study in 11-12-year-old Australian children.

Physical activity (PA) during childhood and adolescence is important for the accrual of maximal peak bone mass. The precise dose that benefits bone remains unclear as methods commonly used to analyze PA data are unsuitable for measuring bone-relevant PA. Using improved accelerometry methods, this study identified the amount and intensity of PA most strongly associated with bone outcomes in 11-12-year-olds. Participants (n = 770; 382 boys) underwent tibial peripheral quantitative computed tomography to assess trabecular and cortical density, endosteal and periosteal circumference and polar stress-strain index. Seven-day wrist-worn raw acceleration data averaged over 1-s epochs was used to estimate time accumulated above incremental PA intensities (50 milli-gravitational unit (mg) increments from 200 to 3000 mg). Associations between time spent above each 50 mg increment and bone outcomes were assessed using multiple linear regression, adjusted for age, sex, height, weight, maturity, socioeconomic position, muscle cross-sectional area and PA below the intensity of interest. There was a gradual increase in mean R2 change across all bone-related outcomes as the intensity increased in 50 mg increments from >200 to >700 mg. All outcomes became significant at >700 mg (R2 change = 0.6%-1.3% and p = 0.001-0.02). Any further increases in intensity led to a reduction in mean R2 change and associations became non-significant for all outcomes >1500 mg. Using more appropriate accelerometry methods (1-s epochs; no a priori application of traditional cut-points) enabled us to identify that ∼10 min/day of PA >700 mg (equivalent to running ∼10 km/h) was positively associated with pQCT-derived measures of bone density, geometry and strength in 11-12-year-olds.

Reliability of muscle thickness and muscle echo intensity evaluation of the posterior medial tibia in long-distance athletes using an ultrasound imaging device.

OBJECTIVE: We aimed to verify the reliability of muscle thickness and luminance evaluation of the deep leg muscles using an ultrasound device. DESIGN: Cohort study. SETTING: Track and field, Participants: high school track and field long distance athletes (N = 10, female: 50.0%, age = 16.0 ± 2.8 years, BMI = 18.2 ± 2.3 kg/m2) PARTICIPANTS: This study included Japanese high school track and long-distance field athletes. MAIN OUTCOME MEASURES: The thickness and echo intensity of tibialis posterior, flexor digitorum longus, and soleus muscles in the posterior medial tibia were clarified. RESULTS: The echo intensity evaluation of the tibialis posterior muscle showed an additive error. CONCLUSION: The study suggested that the results could be clinically applied clinically, except for the evaluation of echo intensity of the posterior tibialis muscle.

Caloric restriction reduces trabecular bone loss during aging and improves bone marrow adipocyte endocrine function in male mice.

Introduction: Caloric restriction (CR) is a nutritional intervention that increases life expectancy while lowering the risk for cardio-metabolic disease. Its effects on bone health, however, remain controversial. For instance, CR has been linked to increased accumulation of bone marrow adipose tissue (BMAT) in long bones, a process thought to elicit detrimental effects on bone. Qualitative differences have been reported in BMAT in relation to its specific anatomical localization, subdividing it into physiological and potentially pathological BMAT. We here examine the local impact of CR on bone composition, microstructure and its endocrine profile in the context of aging. Methods: Young and aged male C57Bl6J mice were subjected to CR for 8 weeks and were compared to age-matched littermates with free food access. We assessed bone microstructure and BMAT by micro-CT, bone fatty acid and transcriptomic profiles, and bone healing. Results: CR increased tibial BMAT accumulation and adipogenic gene expression. CR also resulted in elevated fatty acid desaturation in the proximal and mid-shaft regions of the tibia, thus more closely resembling the biochemical lipid profile of the distally located, physiological BMAT. In aged mice, CR attenuated trabecular bone loss, suggesting that CR may revert some aspects of age-related bone dysfunction. Cortical bone, however, was decreased in young mice on CR and remained reduced in aged mice, irrespective of dietary intervention. No negative effects of CR on bone regeneration were evident in either young or aged mice. Discussion: Our findings indicate that the timing of CR is critical and may exert detrimental effects on bone biology if administered during a phase of active skeletal growth. Conversely, CR exerts positive effects on trabecular bone structure in the context of aging, which occurs despite substantial accumulation of BMAT. These data suggest that the endocrine profile of BMAT, rather than its fatty acid composition, contributes to healthy bone maintenance in aged mice.

The efficacy of physeal bar resection with guided growth in the treatment of physeal arrest with angular limb deformity.

Premature physeal arrest can cause progressive deformities and functional disabilities of the lower limbs. This study addressed the outcomes after physeal bar resection with or without guided growth (temporary hemiepiphysiodesis) for the treatment of angular limb deformities. We retrospectively analyzed 27 patients (mean 9 years; range, 3-12 years) who underwent physeal bar resection of the distal femur (15 patients), proximal tibia (3 patients), and distal tibia (9 patients) between 2002 and 2020. Fifteen patients underwent physeal bar resection only (Group A), and the other twelve underwent simultaneous guided growth (Group B). The correction angle (angle change between the preoperative and last follow-up values) was compared and analyzed. The overall mean correction angle was 2.9° (range, - 9 to 18.3°). A total of 12 (45%) patients had a > 5° angular deformity improvement (mean, 9.6°; range, 5-18.3°), 9 (33%) had a < 5° angular change; and 6 (22%) had a > 5° worsening of the angular deformity (mean, 6.7°; range, 5.2-9°). The correction angle in Group B (mean 7.6° ± 6.2) was significantly higher than that in Group A (mean - 0.77° ± 6.3) (P = 0.01). We found six (40%) and zero patients with a > 5° angular deformity increase in Groups A and B, respectively (P < 0.047). The group that underwent physeal bar resection with guided growth showed significantly higher correction angles than the group that underwent physeal bar resection alone. Additionally, none of the patients in the guided growth group experienced an increased angular deformity. Therefore, combining guided growth with physeal bar resection may lead to better outcomes in the treatment of growth arrest with angular deformities.

Mortality after major lower extremity amputation and association with index level: a cohort study based on 11,205 first-time amputations from nationwide Danish databases.

BACKGROUND AND PURPOSE: Mortality after major lower extremity amputations is high and may depend on amputation level. We aimed to examine the mortality risk in the first year after major lower extremity amputation divided into transtibial and transfemoral amputations. METHODS: This observational cohort study used data from the Danish Nationwide Health registers. 11,205 first-time major lower extremity amputations were included from January 1, 2010, to December 31, 2021, comprising 3,921 transtibial amputations and 7,284 transfemoral amputations. RESULTS: The 30-day mortality after transtibial amputation was overall 11%, 95% confidence interval (CI) 10-12 (440/3,921) during the study period, but declined from 10%, CI 7-13 (37/381) in 2010 to 7%, CI 4-11 (15/220) in 2021. The 1-year mortality was 29% overall, CI 28-30 (1,140 /3,921), with a decline from 31%, CI 21-36 (117/381) to 20%, CI 15-26 (45/220) during the study period. For initial transfemoral amputation, the 30-day mortality was overall 23%, CI 22-23 (1,673/7,284) and declined from 27%, CI 23-31 (138/509) to 22%, CI 19-25 (148/683) during the study period. The 1-year mortality was 48% overall, CI 46-49 (3,466/7,284) and declined from 55%, CI 50-59 (279/509) to 46%, CI 42-50 (315/638). CONCLUSION: The mortality after major lower extremity amputation declined in the 12-year study period; however, the 1-year mortality remained high after both transtibial and transfemoral amputations (20% and 46% in 2021). Hence, major lower extremity amputation patients constitute one of the most fragile orthopedic patient groups, emphasizing an increased need for attention in the pre-, peri-, and postoperative setting.

Nomogram construction and validation of axial deviation in patients with tibial defects treated with the Ilizarov bone transport technique.

INTRODUCTION: The Ilizarov bone transport technique is widely recognised as an effective method for treating large segment bone defects in clinical practice. However, axial deviation is a common complication in the treatment of tibial large segment bone defects, which can have a serious impact on the clinical efficacy of bone transport. Our study aims to construct and validate a nomogram for predicting axial deviation of tibial bone transport. METHOD: This study retrospectively collected data from 363 patients who underwent the tibial Ilizarov technique for bone transport. Univariate and multivariate logistic regression analyses were performed to determine the independent risk factors for axial deviation, which were later used to construct a nomogram. The nomogram was evaluated using the decision curve analysis (DCA), the calibration curve, and the area under the receiver operating characteristic curve (AUC). RESULTS: Of the 363 patients who underwent Ilizarov tibial bone transport, 31.7% (115/363) experienced axial deviation. Multivariate logistic regression analysis showed that gender, height, defect site, and external fixation index were important risk factors for axial deviation. The AUC value of the nomogram model was 0.705. The calibration curve and the decision curve analysis showed a good consistency between the actual axial deviation and the predicted probability. CONCLUSION: The model assigns a quantitative risk score to each variable, which can be used to predict the risk of axial deviation during tibial bone transport.

Ethanol consumption in non-human primates alters plasma markers of bone turnover but not tibia architecture.

Ethanol consumption is associated with positive, negative, and neutral effects on the skeletal system. Our previous work using a nonhuman primate model of voluntary ethanol consumption showed that chronic ethanol use has an impact on skeletal attributes, most notably on biochemical markers of bone turnover. However, these studies were limited by small sample sizes and resulting lack of statistical power. Here, we applied a machine learning framework to integrate data from 155 monkeys (100 ethanol and 55 controls) to identify the bone features associated with chronic ethanol use. Specifically, we analyzed the influence of ethanol consumption on biomarkers of bone turnover and cancellous and cortical bone architecture in tibia. We hypothesized that chronic ethanol use for 6 months to 2.5 years would result in measurable changes to cancellous features and the biochemical markers compared to control animals. We observed a decrease in bone turnover in monkeys exposed to ethanol; however, we did not find that ethanol consumption resulted in measurable changes in bone architecture.

Periprosthetic giant cell tumour of the tibia: en bloc resection and megaprosthesis revision.

We present a case detailing the diagnosis and management of a periprosthetic giant cell tumour in a female patient in her 70s, who had undergone total knee arthroplasty (TKA) for primary osteoarthritis in her right knee 7 years prior. The patient reported 4 months of painful weight-bearing. Various imaging modalities, including plain radiographs, CT scans and MRI, revealed a sizeable lytic lesion beneath the TKA prosthesis, along with loosening of the tibial component.Blood tests and analyses of synovial fluid ruled out periprosthetic joint infection, and a biopsy confirmed the diagnosis of a giant cell tumour of the bone. Treatment entailed en bloc resection of the tumour and revision of the TKA using a hinged, oncological-type megaprosthesis. Surgical procedures involved careful resection of the proximal tibia, preservation of vasculature and the creation of a medial gastrocnemius muscle flap. Following surgery, the patient underwent supervised rehabilitation with a functional brace.

Advancements in health informatics: finite element insights into medial open-wedge high tibial osteotomy and lateral meniscal tears.

Knee medial compartment osteoarthritis is effectively treated by a medial open-wedge high tibial osteotomy (MOWHTO). The feasibility and safety of MOWHTO for mild lateral meniscal tears are unknown. This study examined the feasibility and safety of knee joint weight-bearing line ratio (WBLr) adjustment during MOWHTO with lateral meniscal injuries. We used a healthy adult male's lower extremities computed tomography scans and knee joint magnetic resonance imaging images to create a normal fine element (FE) model. Based on this model, we generated nine FE models for the MOWHTO operation (WBLr: 40-80%) and 15 models for various lateral meniscal injuries. A compressive load of 650N was applied to all cases to calculate the von Mises stress (VMS), and the intact lateral meniscus' maximal VMS at 77.5% WBLr was accepted as the corrective upper limit stress. Our experimental results show that mild lateral meniscal tears can withstand MOWHTO, while severe tears cannot. Our findings expand the use of MOWHTO and provide a theoretical direction for practical decisions in patients with lateral meniscal injuries.

Sex- and age-related differences in kinetics and tibial accelerations during military-relevant movement tasks in U.S. Army trainees.

Lower extremity injuries are prevalent in military trainees, especially in female and older trainees. Modifiable factors that lead to higher injury risk in these subgroups are not clear. The purpose of this study was to identify whether external loading variables during military-relevant tasks differ by age and sex in U.S. Army trainees. Data was collected on 915 trainees in the first week of Basic Combat Training. Participants performed running and ruck marching (walking with 18.1 kg pack) on a treadmill, as well as double-/single-leg drop landings. Variables included: vertical force loading rates, vertical stiffness, first peak vertical forces, peak vertical and resultant tibial accelerations. Comparisons were made between sexes and age groups (young, ≤19 years; middle, 20-24 years; older, ≥25 years). Significant main effects of sex were found, with females showing higher vertical loading rates during ruck marching, and peak tibial accelerations during running and ruck marching (p ≤ 0.03). Males showed higher vertical stiffness during running and peak vertical tibial accelerations during drop landings (p < 0.01). A main effect of age was found for vertical loading rates during running (p = 0.03), however no significant pairwise differences were found between age groups. These findings suggest that higher external loading may contribute to higher overall injury rates in female trainees. Further, higher stiffness during running may contribute to specific injuries, such as Achilles Tendinopathy, that are more prevalent in males. The lack of differences between age groups suggests that other factors contribute more to higher injury rates in older trainees.

Effects of the Application Local Zoledronic Acid On Different Dental Implants in Rats On Osseointegration.

Objective: Recently, a lot of research has been done around the world to popularize the osseointegration of dental implants. In this study, it was investigated the effect of local zoledronic acid application on implants with machined (MAC), resorbable blast materials (RBM), sandblasted and acid-etched (SLA) surface implants integrated in rat tibias. Methodology: A total of 60 female Wistar rats weighing between 270 and 300 g were used in the study. The rats were passing divided into six classes: controls; MAC (n = 10), RBM (n = 10), SLA (n = 10), and local zoledronic acid (LZA) applied groups; LZA-MAC (n = 10), LZA-RBM (n=10) and LZA-SLA (n = 10) and implants were surgically placement into rat tibias in general anesthesia. After a four-week experimental period, the biomechanical bone implant connection level was determined with reverse torque analysis. Results: Osseointegration levels were detected highly in SLA and RBM surface compared with the machined surfaced implants in both control and treatment groups (p < 0.05). Additionally, local application of zoledronic acid in both three groups; implants increased the biomechanic osseointegration level compared with the controls (p < 0.05). Conclusion: In this research, we observe that the local application of the zoledronic acid could increase the osseointegration, and RBM and SLA surface could be better than machined surfaced implants in terms of bone implant connection. In addition, local application of zoledronic acid may be a safer method than systemic application.

Reconstruction of congenital pseudarthrosis of the radius with a vascularized tibial periosteal transplant: A case report.

Congenital pseudarthrosis of the forearm poses a considerable challenge because of its rarity. The objective of this report is to introduce a novel surgical technique for its treatment. Here, we document a case of congenital pseudarthrosis of the radius in a 3-year-old boy diagnosed with type-1 neurofibromatosis. The surgical treatment involved the excision of approximately 9 cm of native radial periosteum and a bifocal radius osteotomy, which was supplemented with a vascularized tibial periosteal transplant to facilitate bone healing. Anastomosis between the anterior tibial vessels and radial vessels was performed. No immediate or late postoperative complications were observed. After 3 weeks, a robust callus formation was observed, and during a follow-up examination 3 years and 4 months later, a wide range of active forearm rotation was noted. This report suggests that vascularized periosteal flaps show promise as a viable treatment option for congenital pseudarthrosis of the forearm. They offer an alternative to vascularized fibular grafts or single-bone forearm constructs.

An in-vitro three-dimensional surgical simulation technique to predict tibial tunnel length in transtibial posterior cruciate ligament reconstruction.

BACKGROUND: During the transtibial posterior cruciate ligament (PCL) reconstruction, drilling depth excessively longer than the tibial tunnel length (TTL) is an important reason to cause popliteal neurovascular bundle injury when preparing the tibial tunnel. This study aims to develop an in-vitro three-dimensional surgical simulation technique to determine the TTL in anteromedial (AM) and anterolateral (AL) approaches. METHODS: A total of 63 knees' 3-dimensional (3D) computed tomography models were included in this study. The SuperImage system was used to reconstruct the 3D knee model and locate the tibial PCL site. The established 3D knee model and the coordinates of the tibial PCL site were imported into Rhinoceros 3D modeling software to simulate AM and AL tibial tunnel approaches with different tibial tunnel angles (TTA). The TTL and the tibial tunnel height (TTH) were measured in this study. RESULTS: In AM and AL tibial tunnel approaches, the TTL showed a strong correlation with the TTA (for AM: r = 0.758, p < 0.001; for AL: r = 0.727, p < 0.001). The best fit equation to calculate the TTL based on the TTA was Y = 1.04X + 14.96 for males in AM approach, Y = 0.93X + 17.76 for males in AL approach, Y = 0.92X + 14.4 for females in AM approach, and Y = 0.94X + 10.5 for females in AL approach. CONCLUSION: Marking the TTL on the guide pin or reamer could help to avoid the drill bit over-penetrated into the popliteal space to damage the neurovascular structure.