Background: Posterolateral elbow instability can be difficult to diagnose. Drop sign and radial head subluxation are frequently reported after lateral collateral ligament complex (LCLc) injuries; however, their physiological ranges and diagnostic utility are not well established. This study aimed to define the physiological range of these markers using computed tomography (CT) and correlate changes in these markers with progressive LCLc injury. Methods: Nine adult cadaveric elbows were mounted on a setting that allows controlled posterolateral distraction at 90° flexion. CT scans were performed before and after distraction to evaluate drop sign and radial head subluxation. The drop sign was measured as the distance between the Trochlear Sulcus and Olecranon (TSO). LCLc injuries were sequentially induced, including annular ligament division and progressive soft tissue lesions, up to complete LCLc disruption. Results: The physiological TSO was 3.3 mm in normal elbow without distraction and increased to 3.8 mm under distraction (P = .02). TSO greater than 4.3 mm was defined as a positive drop sign, and an average TSO of 4.95 mm was observed with a lesion of the capsule and ulnar band of the LCL. The drop sign progressively increased after each stage of LCLc injury, reaching 9.7 mm (95% confidence interval: 8.8-10.5) after complete LCLc disruption. Radial head subluxation also rises from 2.1 mm (95% confidence interval: 1.3-2.8) under distraction in normal elbow to 14.4 mm following complete LCLc lesion (P < .01). Conclusion: CT imaging of the drop sign and radial head subluxation correlates with the severity of LCLc injury. These markers provide valuable diagnostic information for posterolateral elbow instability.
Aim & Background Posterolateral elbow instability can be difficult to diagnose. Drop sign and radial head subluxation are frequently reported after lateral collateral ligament complex(LCLc) injuries, however, their physiological ranges and diagnostic utility are not well established. This study aimed to define the physiological range of these markers using CT and correlate changes in these markers with progressive LCLc injury. Methods Nine adult cadaveric elbows were mounted on a setting that allows controlled postero-lateral distraction at 90° flexion. CT scans were performed before and after distraction to evaluate drop sign and radial head subluxation. Drop sign was measure as distance between Trochlear Sulcus and Olecranon (TSO). LCLc injuries were sequentially induced, including annular ligament division and progressive soft tissue lesions, up to complete LCLc disruption. Results The physiological TSO was 3.3mm in normal elbow without distraction and increased to 3.8mm under distraction (p=0.02). TSO greater than 4.3mm was defined as a positive drop sign and an average TSO of 4.95 mm was observed with a lesion of the capsule and ulnar band of the LCL. The drop sign progressively increased after each stage of LCLc injury, reaching 9.7mm (95 % CI 8.8–10.5) after complete LCLc disruption. Radial head subluxation also rises from 2.1mm (95% CI 1.3–2.8) under distraction in normal elbow to 14.4mm following complete LCLc lesion(p<0.01). Conclusion CT imaging of the drop sign and radial head subluxation correlates with the severity of LCLc injury. These markers provide valuable diagnostic information for posterolateral elbow instability.
Abstract Purpose Bone loss is commonly encountered during revision total knee arthroplasty (R‐TKA), and metaphyseal cones are often used to address these defects. In addition, they can enhance Zone 2 fixation in R‐TKA in the presence of poor bone quality. The aim of this study was to evaluate the short‐term clinical and radiological outcomes of a novel three‐dimensional (3D)‐printed metaphyseal cone in R‐TKA. Methods This single‐centre, single‐surgeon prospective study included all patients who underwent R‐TKA using a novel 3D‐printed anatomical metaphyseal cone (AMF, ENOVIS®) with a minimum follow‐up of 24 months. Patient demographics and operative details were recorded. Postoperative assessments included the Knee Society Score (KSS), Oxford Knee Score (OKS) and Short Form‐12 (SF‐12). Radiographic evaluation focused on radiolucent lines, implant or cone loosening and the cone's ability to replicate proximal tibial anatomy. Complications, reoperations and revisions for any reason were documented. Results Thirty patients (31 knees) underwent R‐TKA with a total of 48 cones (24 tibial and 24 femoral), with a mean follow‐up of 37.3 months (standard deviation [SD] 8.8). In 48.4% of cases, cones were used on both the tibial and femoral sides. No intraoperative fractures occurred during cone preparation. All patients demonstrated significant improvement in clinical outcomes. Radiographic evaluation showed no evidence of cone loosening and accurate reproduction of proximal tibial anatomy. Survivorship free from cone revision, including for aseptic loosening, was 100%. Survivorship free from any revision or reoperation was also 100%. Conclusion This novel 3D‐printed anatomical metaphyseal cone demonstrated excellent short‐term outcomes, with no early loosening and accurate replication of proximal tibial morphology. However, longer‐term follow‐up and a larger cohort are required to confirm these preliminary findings. Level of Evidence Level IV.
Introduction:Complex proximal ulna fractures that are associated with radial head dislocation or fracture-dislocation, often referred to as "Monteggia-like" or trans-ulnar fracture-dislocations, constitute a heterogeneous group that poses challenges for classification and treatment. Management often relies on surgeon expertise rather than systematic approaches, leading to poor outcomes, high complication rates, and frequent surgical revisions. We hypothesize that a systematic, coronoid-centric, step-by-step surgical technique could improve outcomes in trans-ulnar fracture-dislocations. Methods:A retrospective study was conducted on patients with trans-ulnar fracture-dislocations treated between 2017 and 2023. Exclusion criteria included patients younger than 18 years, open fractures beyond Gustilo grade 1, and follow-up shorter than 12 months. Fractures were classified using the coronoid-centric Mayo classification based on preoperative radiographs and CT scans. Two additional fracture patterns, characterized by distinct coronoid detachment features, were identified. Outcomes were evaluated through subjective elbow scores Subjective Elbow Value, Mayo Elbow Performance Score (MEPS), Oxford Elbow Score, QuickDASH, and range of motion (ROM) evaluations. Results:Among the 39 patients included, the most common fracture pattern was the trans-ulnar basal coronoid fracture-dislocation (49%). At a mean follow-up of 3.9 years (range 1-7), 90% (35/39) of the patients achieved a functional ROM. The mean MEPS was 85 (range 60-100), and the mean QuickDASH was 18 (range 0-45). The revision rate was 13% (5/39), due to coronoid nonunion (n = 1), olecranon fixation failure after a new trauma (n = 1), and elbow stiffness (n = 3). Ulnar nerve neuropathy was recorded in 2 of 39 patients. Discussion:A systematic, coronoid-centric surgical approach led to satisfactory outcomes in trans-ulnar fracture-dislocation with an acceptable rate of complication and revision rate. Recognizing the prognostic value of the coronoid may reduce complication rates. Level of Evidence:Level III. See Instructions for Authors for a complete description of levels of evidence.
Background and Objectives: Total knee arthroplasty (TKA) is one of the most common medical procedures worldwide. However, 10 to 20% of patients are still dissatisfied despite implants and surgical technique advancements. Recently, several medial-stabilized TKAs have been developed in attempts to replicate the native kinematics of the knee. The aim of this scoping review on medial-stabilized TKA inserts—medial congruent (MC) and medial pivot (MP)—is to focus on their clinical outcomes and the role of the posterior cruciate ligament (PCL), aiming to systematically map the existing research and highlight current knowledge gaps. Materials and Methods: A search of the PubMed, Embase and Cochrane databases was performed to identify relevant studies on the kinematics and outcomes of medial pivot (MP) or medial congruent (MC) inserts. The following Mesh terms were used in combination with the Boolean operators “AND” and “OR”: “total knee arthroplasty”, “total knee replacement”, “medial pivot”, “medial congruence”, “outcomes” and “kinematic”. Original studies reporting on clinical outcomes assessed with validated patient-reported scales, surgical techniques and reoperation rates for any reason with a minimum follow-up of 18 months were included. Results: A total of 39 articles met the inclusion criteria, accounting for 6143 total knee replacements. The overall reoperation-free survivorship rate was 98.4% (6047 out of 6143 knees) at a weighted average follow-up of 6.3 years (range 1.5–15.2 years, SD 0.7). Both MP and MC inserts demonstrated good outcomes, with no differences between groups. Few studies evaluated the role of the PCL in MP and MC inserts, with no differences in terms of clinical outcomes between retaining and sacrificing the PCL. Conclusions: MS-TKA demonstrated good outcomes in the literature independently of the specific design (medial pivot or medial congruent). Different possible biases may be present when evaluating the outcomes of these inserts, including different types of alignment and soft tissue balancing philosophies.
Musculoskeletal pain is a major burden in our society. Management of musculoskeletal pain or injuries includes both pharmacological and non-pharmacological approaches, including heat therapy (HT). HT is a well-established treatment option due to its ability to promote muscle relaxation, enhance blood circulation, and modulate nociceptors with a good safety profile. The main focus of this paper is to review the available literature about HT in knee pathologies (i.e., arthrosis, arthritis, traumatic pathologies in the subacute phase, muscle and tendon pathologies linked to fatigue, muscle tension and distractions) and to provide an expert opinion in case of lack of data.
Hip replacement surgery is increasingly being performed on older patients, raising the risk of periprosthetic proximal femur fractures (PPFFs). While the impact of surgery timing on mortality in proximal femoral fractures is established, its effect on PPFFs remains unclear. This study aims to examine the correlation between surgery timing and mortality in PPFF patients. In a historical cohort study, we analyzed data from 79 PPFF patients treated from 2012 to 2022. Patients were categorized by surgery timing (≤48 h, 32 patients vs. >48 h, 47 patients). Outcomes and mortality rates were compared. No significant difference in mortality was observed between patients undergoing early (<48 h) and delayed (>48 h) surgery at 30 days and 1 year. Factors such as age (p = 0.154), gender (p = 0.058), ASA score (p = 0.893), Vancouver classification (p = 0.577), and surgery type (implant revision p = 0.691, OR = 0.667) did not affect 30-day mortality. However, 1-year mortality was influenced by gender (male p = 0.045) and age (p = 0.004), but not by other variables (Vancouver classification p = 0.443, implant revision p = 0.196). These findings indicate no association between surgery timing and mortality in PPFF patients, suggesting that other factors may influence outcomes. Further research is needed to optimize PPFF management.
Knee stiffness is a widely known and worrying condition in several postoperative knees. Less is known about native stiff knee. The aim of this manuscript is to summarize the available literature on native stiff knee epidemiology, classification and treatment. In 1989 stiff knee was defined as a knee with less than 50° of total range of motion. If range of motion is <30°, it is defined as an ankylosed knee. Knee stiffness can be divided into three main types: flexion contractures, extension contractures, and combined contractures. Different risk factors have been associated to native stiff knee and grouped into modifiable or not modifiable. Furthermore, risk factors can be divided into patients' related no patients'-related. Different treatment modalities can be indicated to treat knee stiffness, including manipulation under anesthesia (MUA), arthroscopic and open surgical release. When stiffness is associated with articular disruption TKA represent an option. TKA in native stiff knee can be challenging for the surgeon. Implant's choice and knee exposure are the first steps. In some cases, additional release and extensive can be considered. A stepwise approach and careful preoperative planning are mandatory to obtain long-term satisfactory outcomes. Native stiff knee is a rare but invalidating condition. Different treatment modalities have been proposed as treatment. However, considering that it is frequently associated to sever arthritis, TKA can be an option in painful stiff knees. Nature of knee stiffness necessitates a customized approach to ensure successful management and achieve satisfying outcomes.
In pediatric anterior cruciate ligament reconstruction, many factors should be considered: (1) risk of growth disturbance; (2) high risk of re-tear; (3) determination of the skeletal age, which is sometimes challenging; and (4) no single technique indicated for all patients. The choice of the technique mostly depends on the patients' age and growth potential. Whereas prepubescent patients can be safely treated with physeal sparing techniques (i.e., the Kocher-Micheli technique or its modifications), in postpubescent patients physeal respecting or adult-type reconstructions are generally indicated. In pubescent patients, both all-inside all-epiphyseal and partial transphyseal techniques can be safely performed, but these are not without shortcomings. With the goal of overcoming some of the drawbacks of the existing techniques, the authors describe this technical note. The technique entails an over-the-top femoral position of a 6-strand hamstring graft and an all-epiphyseal tibial tunnel. The femoral physis is completely preserved, and only a 4.5 mm transphyseal tunnel is drilled in the tibia with an all-epiphyseal tibial half socket. With this technique, the graft diameter is adequate, there is no need for fluoroscopy, no risk of graft/tunnel mismatch, and a modified Arnold-Coker lateral tenodesis can be associated via the same lateral incision.
BACKGROUND:The lateral extra-articular tenodesis (LET) procedure associated with anterior cruciate ligament (ACL) reconstruction can be considered in selected patients to diminish the risk of persistent rotatory instability and achieve a protective effect on the graft. Several techniques have been described in the literature to treat rotatory instability. Usually, a strip of the iliotibial band (ITB) is harvested from its middle while leaving the distal insertion, then passed underneath the lateral collateral ligament and fixed on the lateral aspect of the distal femur with various fixation methods such as staples, screws, anchors or extracortical suspensory devices. Despite their effectiveness, these fixation methods may be associated with complications such as lateral pain, over-constraint and tunnel convergence. METHODS:This study presents a detailed surgical description of a new technique to perform an LET during ACL reconstruction with any type of graft fixing the ITB strip with the sutures of the ACL femoral button, comparing its pros and cons in relation to similar techniques found in the literature. CONCLUSIONS:This technique represents a reproducible, easy to learn and inexpensive solution to perform a lateral extra-articular tenodesis associated with an ACL reconstruction using the high-resistance sutures of the femoral button.
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.
Background: Complications such as periprosthetic fractures necessitate challenging revision surgeries. In particular, femoral stem revisions can be complicated by poor bone quality, making primary stability and leg length restoration difficult to achieve. Modular fluted tapered stems (MFTSs) have emerged as a viable option for these complex cases. This study aims to describe a reproducible three-step technique for femoral stem revision using MFTSs. The technique focuses on (1) obtaining distal primary stability, (2) restoring leg length, and (3) ensuring overall implant stability. Materials and methods: We conducted a retrospective analysis of ten patients who underwent revision THA using this three-step technique, with a minimum follow-up of 12 months. The mean patient age was 70.7 years, and the average follow-up was 24.2 months. Limits were the small sample size, the lack of clinical outcomes and the short-term follow-up. Results: There was no subsidence, a mean leg length discrepancy of 4 mm (p: 0.604), and no dislocations. However, heterotopic ossifications (HOs) were observed in 25% of patients, although no trochanteric migrations occurred. One patient experienced an intraoperative femoral fracture, which was successfully treated. Conclusions: This three-step approach can break down the revision procedure, making it more accessible to surgeons. The findings suggest that this technique is effective in achieving reliable outcomes in femoral stem revisions, potentially improving the standard of care for patients requiring complex THA revisions.
PurposeDifferent methods for quantifying joint-line obliquity (JLO) have been described, including joint-line obliquity angle (JLOA), Mikulicz joint-line angle (MJLA) and medial proximal tibial angle (MPTA). The goal of the present study was to quantify the variation of JLOA based on the position of the hip. The hypothesis of our study is that JLO is significantly influenced by the abduction/adduction of the limb, unlike MJLA.MethodsOne hundred long-leg-weightbearing X-rays were used. At time 0 and after 30 days, two observers performed different measurements, including (1) distance between pubic symphysis and center of the femoral head, (2) distance between center of the femoral head and center of the ankle joint, (3) distance between center of the ankle and medial malleolus, (4) hip-knee-ankle angle, (5) MPTA, (6) lateral distal femoral angle, (7) joint-line congruency angle, (8) JLOA, (9) MJL and (10) angle between Mikulicz line and line perpendicular to the ground. The changes of the JLOA based on the position of the hip (abducted, neutral, bipedal stance adduction and monopodal stance adduction) were calculated with trigonometric formulas and with simulation on an orthopaedic planning digital software.ResultsThe JLOA change between adducted and abducted positions was on average 12.8 degrees (SD 0.9 mm). The MJL did not vary significantly based on hip position.ConclusionsThe adduction/abduction of the lower limb has a considerable impact on JLOA. Methods like MJLA which are not affected by hip position should be preferred for JLO evaluation.Level of EvidenceDiagnostic study, level III.
Total knee arthroplasty (TKA) is a successful and highly effective procedure in most patients with tricompartmental knee arthritis. Despite the innovations in surgical techniques due to planning software and technological innovations, patients’ dissatisfaction after TKA is still high, at up to 20%. Robotic-assisted surgery (RAS) could be considered as a future option for improving outcomes due to its higher accuracy, precision, and reliability. Robotic systems can be classified as fully active, semi-active, or passive depending on the surgeon’s involvement during the procedure, and as imageless or image-based according to the necessity of radiological exams for the pre-operative planning. Three of the most well-known robotic systems for knee surgery are MAKO® (Stryker Ltd., Kalamazoo, MI, USA), NAVIO® (Smith & Nephew, Andover, TX, USA), and ROSA® (Zimmer Inc., Warsaw, IN, USA). These systems show differences in terms of surgeon involvement, the use of CT scans or X-rays for pre-operative planning, the possibility to perform both unicompartmental knee arthroplasty (UKA) and TKA (or even total hip arthroplasty THA), and in the different kinds of knee prosthesis that can be implanted. This article aims to describe the features of the most used robotic systems for knee arthroplasty, to examine their outcomes and analyze their cost-effectiveness, and to evaluate future perspectives.
The aim of this study was to evaluate the accuracy of a patient-specific cutting guide on both coronal and sagittal alignment compared to the pre-operative planning in OWHTO. Twelve OWHTO on 6 cadaveric specimens were performed by 3 experienced knee surgeons using patient-specific cutting guides based on 3D pre-operative planning. Since the specimens had no major deformities, a fixed correction of 6° on the left and 10° on the right legs were carried out to simulate different scenarios. A pre-operative and post-OWHTO 3D CT scans were performed, and images were superimposed using the dedicated 3D planning software to align their reference axes. A pre-operative planning was performed considering both Medial Proximal Tibial Angle (MPTA) and Posterior Tibial Slope (PTS), and a patient-specific cutting guide was produced. Planned and post-OWHTO MPTA and PTS were evaluated (mean and standard deviation), and Pearson’s correlation coefficient was calculated to assess precision and accuracy of the whole treatment. A mean correction of 6,1° (SD 1,9°) and 1,2° (SD 1°) was obtained respectively in the coronal plane (MPTA) and in the sagittal plane (PTS). The average difference between planned and post-OWHTO MPTA and PTS was respectively 1,2° (SD 0,6°) and 1,2° (SD 1°) in the sagittal plane (PTS). Pearson’s correlation coefficient demonstrated a good accuracy of the treatment in both coronal and sagittal plane (respectively r=0,95 and r=0,86). No lateral hinge fractures were detected at the post-operative CT scan. OWTHO performed with the help of 3D patient specific cutting guide on cadaveric specimens demonstrated good accuracy and reliability in obtaining the planned correction. In vivo studies are necessary to confirm these results and evaluate cost-effectiveness of this system. Level IV cadaveric study.
Background: Femoral nailing is a largely widespread procedure in the elderly population, and the number of these surgeries is rising. Hip arthroplasty is a salvage procedure performed to improve function of the hip after femoral nail failure. The aim of the study is to evaluate functional outcomes, complications and survivorship in hip arthroplasty after femoral nail failure. Methods: A systematic review of three databases (Pubmed, Embase and Cochrane) was performed using the PRISMA 2020 guidelines. After selection, four studies met the inclusion criteria, and 483 treated hips have been analyzed (476 total hip arthroplasties, 7 partial hip arthroplasties). Results: The median value of Harris Hip Score (HHS) after salvage treatment was 86.1. The main indications for salvage treatment were osteoarthrosis, avascular necrosis of the femoral head and instability of the hip. Complications are more frequent than in primary total hip arthroplasty, in particular aseptic loosening and dislocation. Good outcomes have also been achieved using revision-type stems and proximal femoral replacements (PFR). Conclusions: Conversion total hip arthroplasty is confirmed as the optimal treatment for femoral nail failure in the elderly population. Cemented or hybrid total hip arthroplasties have better outcomes than uncemented total hip arthroplasties, and the use of different types of implants widens the possible approaches to surgery in restoring the biomechanics of the hip and increases the satisfaction of patients.
Three-dimensional (3D) printing was introduced firstly for industrial use, but it gained popularity in different medical fields, including orthopedic surgeries. Particularly, 3D-printed models have been used in the pre-operative planning for spine surgery, oncology, acetabular fracture treatment and complex primary total hip arthroplasty (THA) or revision THA. In knee surgery, some authors described good accuracy with 3D-printed wedge for Opening Wedge High Tibial Osteotomy (OWHTO), but there are no studies describing its application in Total Knee Arthroplasty (TKA). In both primary and revision TKA, a 3D-printed model may be useful to better evaluate knee morphology and deformity, implants, bone losses and the compatibility between different components used. Furthermore, some companies provide a bone thickness evaluation, which may be useful to identify zones at risk of intra-operative fracture, especially in those cases in which a cone or sleeve must be used. The first aim of this manuscript was to evaluate possible application of 3D-printed model in pre-operative planning of both complex primary and revision TKA, compared to standard planning. Two clinical cases will also be described to show how these models can be used for planning purposes.
Background The aim of this study is to find a correlation between linear measurements and the graft length required for different anterior cruciate ligament (ACL) revision techniques, to extract formulas to predict required graft length during the preoperative planning. Methods At time 0 and 30 days later, two observers measured eight linear distances on standard 2D knee magnetic resonance imaging (MRI), and nine curved distances on 3D MRI sequences, corresponding to different techniques for ACL revision, anatomic anterolateral ligament (ALL) reconstruction, and lateral extrarticular tenodesis (LET). Intra- and interobserver reliability was tested for 2D and 3D measurements. The correlation between 2D and 3D measurements was tested. The 2D measurements with highest repeatability and reproducibility, and with strongest correlation with 3D measurements were used to extract formulas to calculate the graft length from 2D values. Results Fifty MRIs acquired with both 2D and 3D sequences were used. The intra- and interobserver reliability of linear 2D measurement was high, with the transepicondylar distance (TD) showing the highest reproducibility and repeatability. The intra- and interobserver reliability of 3D measurements was lower than 2D, but acceptable for all measurements except for ALL reconstruction. The TD showed the strongest correlation with 3D measurements. The formulas extracted to calculate the graft length from the TD proved to be accurate. Conclusion Accurate formulas were created to calculate the graft length needed for different ACL revision techniques and ALL reconstruction/LET techniques from TD. These formulas can be used during preoperative planning of ACL revision cases.
Importance: Tibial tubercle osteotomy (TTO) is indicated to treat patellofemoral (PF) malalignment and chondral disease refractory to conservative treatment. However, there are no systematic reviews describing TTO outcomes in chondral damages without instability. Aim: The aims of this study were to (1) assess the quality of the published studies, (2) identify indication for TTO to treat PFP with chondral disease without instability, (3) evaluate the most common TTO techniques, (4) evaluate the clinical outcomes, and (5) evaluate TTO's complication and failure rates. Evidence review: In December 2020, a literature search was performed applying the following criteria: (1) peer reviewed Level 1-4 studies; (2) English language; (3) human subjects with clinical and/or radiological outcomes; (4) TTO alone or associated with minor cartilage procedure (only drilling, no instability); (5) minimum follow-up 12 months, minimum 10 patients; and (6) no more than 20% of drop-out rate. Data from studies were collected and described with weighted averages and standard deviations. Findings: A total of 18 Level 4 studies were included. The average Coleman Methodology Score was 61.5 points (range 48-81). A total of 851 patients (892 knees) were included, with 64.8% of female patients. The weighted average follow-up was 49.1 months (range 12-128.5). Indication for TTOs was poorly described. The main technique used was anteromedialisation (60.4%). In 27.7% of the cases, TTO was associated with lateral release. Different scoring systems were used to evaluate outcomes, with significant improvements. The average rate of good/excellent results was 78.7% (range 57%-100%). Fifteen studies described the complication rate (9.9%), whereas only four reported the failure rate (6.2%). Conclusion and relevance: TTOs performed to treat PF malalignment associated with chondral disease without instability provided good clinical outcomes, with acceptable complication/failure rates. However, high-level studies are necessary because of studies' heterogeneity regarding patellofemoral malalignment and chondral disease treatment. Study design and level of evidence: Systematic review. Level IV. Level of the study: Level IV, systematic review of Level IV studies.