Minimum four-year clinical outcomes after on-table reconstruction technique for Dubberley type III in coronal shear fractures of the capitellum and trochlea: a report of 10 patients.

PURPOSE: Comminuted coronal shear fractures of the distal humerus represent rare injuries and are difficult to treat, especially comminuted capitellum and trochlear fractures (Dubberley Type III). The on-table reconstruction technique of comminuted articular fractures may be an option, although it has not been reported in the coronal shear fracture of the distal humerus. The aim of the present case series is to determine the functional and radiological outcomes of on-table reconstructed Dubberley III fractures. METHODS: A retrospective review was conducted of 10 patients with Dubberley type III fractures in coronal shear fractures of the capitellum and trochlea who underwent an 'on-table' reconstruction technique between January 2009 and October 2019. All patients were evaluated using the disabilities of the arm, shoulder, and hand (DASH) score, American Shoulder and Elbow Surgeons(ASES) score, Mayo Elbow Score Performance Index (MEPI) score and at least 4 years later. RESULTS: All cases achieved union. At the final follow-up, the mean range of elbow motion was 11.5°of flexion contracture and 131.9° of further flexion. The mean DASH score was 21.2 (5.7) points (range 13.3-32.5). The mean ASES score was 88.6 ± 7.4 (range, 77 to 100). The mean MEPI score was 87 (10) points (range 70-100). In complication, partial osteonecrosis of capitellum is developed in one patient. One patient had heterotopic ossification without functional impairment. CONCLUSION: The on-table reconstruction technique can be a reliable option in the surgical treatment of complex distal humerus fractures. This technique allows anatomical reduction of comminuted capitellum and trochlea, with a low risk of avascular necrosis over 4 years of follow-up. LEVEL OF EVIDENCE: Level IV, retrospective case series.

High rates of return to sport following management of osteochondritis dissecans of the femoral trochlea: A systematic review.

PURPOSE: To summarize management strategies and associated clinical outcomes in patients with osteochondritis dissecans (OCD) of the femoral trochlea. METHODS: Three databases were searched from inception to 2 October 2023, for studies describing outcomes posttreatment for femoral trochlear OCD. The authors adhered to the preferred reporting items for systematic reviews and meta-analyses and revised assessment of multiple systematic reviews guidelines as well as the Cochrane Handbook for Systematic Reviews of Interventions. Data on demographics, injury characteristics, and operative details were extracted. Outcomes included patient reported outcome measures (PROMs), complications, and revision and return to sport (RTS) rates. RESULTS: Twenty studies comprising 105 patients (119 knees) were included. Females comprised 10.1% (range: 0%-100%) of patients and the mean age of patients was 14.5 (range: 11-28) years. A total of 89 (74.7%) of knees received operative management, with 28 of 34 (82.4%) known open procedures being open reduction internal fixation (ORIF), and nine of 29 (31%) known arthroscopic procedures receiving arthroscopic reduction internal fixation (ARIF) or drilling. Lysholm and International Knee Documentation Committee scores in 20 patients each ranged from 93.4 to 100 and 74.7 to 96.6, respectively. The revision rate for operative procedures was 9.0%, and the overall RTS rate was 93.3%. CONCLUSION: There is very little high quality evidence investigating patients with femoral trochlear OCD lesions. Drilling, ARIF, and ORIF were the most common surgical options for this patient population. Patients treated with either nonoperative or operative management returned to sport at a high rate, and those requiring operative management had a low revision rate. LEVEL OF EVIDENCE: Level V.

The role of the most cranial trochlear orientation in patellar maltracking to better characterise trochlear morphology.

PURPOSE: The purpose of our study is to describe a magnetic resonance imaging quantitative parameter to assess the morphology of the trochlea that could be measurable from normal to high-grade trochlear dysplasia while evaluating the most proximal slice with trochlear cartilage. METHODS: Two groups of patients have been compared: patients with no patellofemoral pain, no previous trauma and undergoing surgery for a suspected isolated meniscal tears (group A) and patients with objective patellar instability (group B). The cranial trochlear orientation (CTO) angle is defined as the angle between the posterior bicondylar line and the most lateral and most medial points on the subchondral bone covered by cartilage digitised on the first and most cranial image with the trochlear cartilage clearly visible. RESULTS: The final cohort included 253 patients (109 in group A and 144 in group B). CTO was significantly higher in group B (-2.5 ± 8.4 vs. -10.8 ± 5,1; p < .001). Moreover, 75% of knees in group B had a CTO > -7°, while 75% of knees in group A had a CTO < -7°. CTO was measurable in all 253 knees, whereas the lateral trochlear inclination and the sulcus angle were measurable in only 202 knees. The entire cohort was also divided into knees with CTO ≤ 0° and CTO > 0°. All knees with a CTO > 0 were in group B, and 49% of knees with CTO < 0 were in group B. CTO was positively correlated with lateral patellar tilt. CONCLUSIONS: CTO is the only parameter that can be measured on the most cranial slice, in every patient, even in high-grade trochlear dysplasia. According to this new system, the axial trochlear shape may be divided into two types: a positive CTO and a negative CTO, with the trochlea serving, respectively, as a medial and lateral barrier. LEVEL OF EVIDENCE: Level III.

Sulcus-deepening trochleoplasty grants satisfactory results with minimal patellofemoral arthritis at 23-30 years of follow-up.

PURPOSE: The purpose of this study was to evaluate the radiographic and clinical outcomes of sulcus-deepening trochleoplasty at a minimum follow-up of 23 years. METHODS: The authors evaluated a retrospective series of 10 patients (11 knees) who underwent trochleoplasty between 1993 and 2000. All patients were assessed at a minimum follow-up of 23 years by an independent clinician who noted any patellar redislocations and collected the International Knee Documentation Committee (IKDC), Kujala scores and range of motion. Radiographic examination was performed to assess patellofemoral arthritis using the Iwano classification. RESULTS: A total of 11 knees, from five women and five men aged 25.6 ± 6.9 years (range, 15-47 years) underwent trochleoplasty during the inclusion period. All 11 knees underwent adjuvant procedures during trochleoplasty (100%): 10 had tibial tuberosity osteotomy (TTO) and vastus medialis plasty and 1 had only vastus medialis plasty (had prior TTO). At a follow-up of 24.4 ± 2.1 years (range, 23-30 years), two patients were lost to follow-up (18%). The Iwano classification was Grade 1 in three patients (33%), Grade 2 in four patients (44%) and Grade 4 in two patients (22%). The flexion range was 130 ± 8.7° and satisfaction was 9.2 ± 0.7, Kujala was 76.9 ± 8.5 and IKDC was 65.5 ± 13.8. CONCLUSION: At 23-30 years following sulcus-deepening trochleoplasty in this small series of 10 patients (11 knees), patients had satisfactory clinical scores, only 1 patient reported an episode of traumatic patellar dislocation, and two knees had patellofemoral arthritis of Iwano Grade >2 (22%). LEVEL OF EVIDENCE: Level IV.

The effect of different alignment strategies on trochlear orientation after total knee arthroplasty.

PURPOSE: When planning and delivering total knee arthroplasty (TKA), there are multiple coronal alignment strategies such as functional alignment (FA), kinematic alignment (KA), mechanical and adjusted mechanical alignment (MA, aMA). Recent three-dimensional and robotic-assisted surgery (RAS) studies have demonstrated that KA potentially better restores the trochlear anatomy than MA. The purpose of this study was to compare the restoration of the native trochlear orientation in patients undergoing RAS TKA using four different alignment strategies. It was hypothesised that FA would result in the lowest number of outliers. METHODS: This is a prospective study of 200 patients undergoing RAS-TKA with a single implant. All patients were analysed for MA and KA prebalancing, and 157 patients received aMA and 43 patients FA with intraoperative balancing. Preoperative transverse computed tomography scans were used to determine the posterior condylar axis (PCA), lateral trochlear inclination (LTI) angle, sulcus angle (SA) and anterior trochlear line (ATL) angle. Implant measurements were obtained using a photographic analysis. Intraoperative software data combined with implant data and preoperative measurements were used to calculate the differences. Outliers were defined as ≥3° of alteration. Trochlea dysplasia was defined as LTI < 12°. RESULTS: Native transepicondylar PCA had a median of 2°, LTI 18°, SA 137°, ATL 4°. LTI outliers were observed in 47%-60% of cases, with KA < FA < aMA < MA. For ATL, the range of outliers was 40.5%-85%, KA < FA < aMA < MA. SA produced 81% of outliers. Of all median angle values, only LTI when using KA was not significantly altered compared to the native knee. CONCLUSION: There is a significant alteration of trochlear orientation after TKA, regardless of the alignment strategy used. KA produced the lowest, but a substantial, number of outliers. The uniform design of implants causes the surgeon to compromise on balance in flexion versus trochlear position. The clinical relevance of this compromise requires further clinical investigations. LEVEL OF EVIDENCE: Level II, prospective cohort study.

Kinematic alignment adequately restores trochlear anatomy, patellar kinematics and kinetics in total knee arthroplasty: A systematic review.

PURPOSE: Patellofemoral pain, maltracking and instability remain common and challenging complications after total knee arthroplasty. Controversy exists regarding the effect of kinematic alignment on the patellofemoral joint, as it generally leads to more femoral component valgus and internal rotation compared to mechanical alignment. The aim of this systematic review is to thoroughly examine the influence of kinematic alignment on the third space. METHODS: A systematic search of the Pubmed, Cochrane and Web of Science databases was performed to screen for relevant articles published before 7 April 2024. This led to the final inclusion of 42 articles: 2 cadaveric, 9 radiographic, 12 computer simulation and 19 clinical studies. The risk of bias was evaluated with the risk of bias in non-randomised studies - of interventions tool as the lowest level of evidence of the included clinical studies was IV. The effects of kinematic alignment on patellar kinematics and kinetics, trochlear anatomy reconstruction and patellofemoral complication rate were investigated. RESULTS: Kinematic alignment closely restores native patellar kinematics and kinetics, better reproduces native trochlear anatomy than mechanical alignment and leads to a 0%-11.4% incidence of patellofemoral complications. A more valgus joint line of the distal femur can cause lateral trochlear undercoverage and a trochlear angle orientation medial to the quadriceps vector when applying kinematic alignment, both of which can be solved by using an adjusted design with a 20.5° valgus trochlea. CONCLUSION: Kinematic alignment appears to be a safe strategy for the patellofemoral joint in most knees, provided that certain precautions are taken to minimize the risk of complications. LEVEL OF EVIDENCE: Level IV clinical studies, in vitro research.

Decreased femoral trochlea axial orientation corrected by derotational distal femur osteotomy in patients with patellar dislocation yields satisfactory outcomes.

PURPOSE: The femoral trochlea axial orientation has been shown to be a better predictor of patellar dislocation than the femoral anteversion angle. However, no study has investigated the importance of the femoral trochlea axial orientation in the surgical treatment of patellar dislocation. It is aimed to explore the pathological threshold of the femoral trochlea axial orientation and its guiding implications for surgical interventions in the study. METHODS: Sixty-four patients with patellar dislocation and 64 controls were included for measurement of the femoral trochlea axial orientation. The ability to predict the patellar dislocation and the pathologic threshold of the femoral trochlea axial orientation were evaluated using the receiver operating characteristic curve. One hundred patients with medial patellofemoral ligament reconstruction and 25 patients with derotational distal femur osteotomy were divided into two groups based on the femoral trochlea axial orientation cut-off value and their postoperative knee functions, and patellar tilt angles were compared. RESULTS: There were significant differences in the femoral trochlea axial orientation (60.8 ± 7.9 vs. 67.8 ± 4.6, p < 0.05) between patients with patellar dislocation and the normal population. The sensitivity and specificity of the femoral trochlea axial orientation were 0.641 and 0.813, respectively, at the femoral trochlea axial orientation smaller than 63.8°. Amongst patients having had isolated medial patellofemoral ligament reconstruction with decreased femoral trochlea axial orientation, knee function was poorer after surgery. The prognosis of patients with the femoral trochlea axial orientation correction in derotational distal femur osteotomy was better than that for patients without correction. CONCLUSIONS: The femoral trochlea axial orientation had good predictive efficiency for patellar dislocation. Isolated medial patellofemoral ligament reconstruction is not sufficiently effective for patients with patellar dislocation and decreased femoral trochlea axial orientation. Patients with a decreased femoral trochlea axial orientation can have better surgical outcomes after correction by derotational distal femur osteotomy. LEVEL OF EVIDENCE: Level III.

Medial Femoral Trochlea Osteochondral Flap Reconstruction of the Previously Unsalvageable Kienbock-Associated Lunate With a Coronal Split.

PURPOSE: Patients with Kienbock disease can present with coronal fracture and collapse of the proximal lunate (Unified B2/Bain grade 1, 2B). Traditionally, this was considered unsalvageable. However, medial femoral trochlea (MFT) osteochondral reconstruction, used to recreate the proximal lunate surface, can be paired with reduction and repair of the coronal plane fracture, thus restoring midcarpal congruity. The purpose of this study was to report radiographic and clinical outcomes following lunate coronal fracture fixation at the time of MFT osteochondral reconstruction. METHODS: This was a retrospective study performed at a single institution. We identified patients with Kienbock disease who underwent MFT osteochondral reconstruction from 2014 to 2023. Patients were included if they had a coronal fracture of the lunate distal articular surface fixed at the time of surgery. Radiographic and clinical parameters were evaluated, including carpal height ratio, union rate, presence of heterotopic ossification, need for revision surgery, and patient-reported outcome measures. RESULTS: Thirty-three patients were included, with a mean age of 27.5 years (range: 15-41); 19 (58%) were women. Mean radiographic follow-up time was 5.8 months, and mean clinical follow-up time was 22.6 months. Union was achieved in 30/33 patients (91%). Carpal height ratio improved from 1.32 to 1.4. Two patients (6%) required reoperation, one for removal of heterotopic ossification and another for conversion to proximal row carpectomy. Patients demonstrated meaningful improvement in brief Michigan Hand Questionnaire and Patient-Reported Outcomes Measurement Information Upper Extremity scores. Range of motion before and after surgery was similar. CONCLUSIONS: Lunate coronal fracture fixation with MFT osteochondral reconstruction represents an additional management option in select patients with Kienbock disease. This technique restores the midcarpal joint during lunate reconstruction and may allow patients to avoid salvage procedures. Early radiographic and clinical outcomes are promising. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Trochlea morphology demonstrates variability but no gender difference in osteoarthritic patients undergoing total knee arthroplasty.

BACKGROUND: In recent years, coronal lower leg alignment has received significant attention. Two classifications recently described the variability in both femoral and tibial morphology, resulting in differing native lower limb alignment. The native trochlea and the variability in morphology has received less attention. METHODS: This is a prospective cohort study of 200 patients undergoing robotically assisted TKA. Preoperative transverse CT scans were used to determine the posterior condylar axis (PCA), transepicondylar axis (TEA), lateral trochlear inclination (LTI), the sulcus angle (SA) and the anterior trochlear line (ATL). Outliers were defined as values > 1.5 IQR from median value. Trochlea dysplasia was defined as LTI < 12°. Gender differences were compared. RESULTS: In total, 99 patients were female (49.4%). SA had a median of 137.0° (IQR 12°), ATL 4° (IQR 4), LTI 18° (IQR 7°). Median TEA-PCA was 5° external (IQR 3°). There were 5.0% outliers in SA, 3.0% of outliers in ATL, 3.5% outliers in LTI and 4.5% outliers in the TEA-PCA. Trochlear dysplasia was present in 11.5% of the measurements. There was no difference in any of the angles between the genders. CONCLUSION: The present study demonstrates no difference in trochlea morphology between the genders, rather a significant number of overall outliers in trochlear morphology. Larger cohorts but also, more investigations, are needed to better understand the trochlear morphology of patients undergoing total knee arthroplasty. The personalized alignment strategies and implants need to account for this variability in the population.

Matrix-Assisted Autologous Chondrocyte Transplantation for the Treatment of Patellofemoral Chondral Lesions: Long-term Results at a Minimum 15-Year Follow-up.

BACKGROUND: A few studies have documented the long-term results of chondrocyte-based procedures for the treatment of patellofemoral cartilage lesions, but specific results are lacking after matrix-assisted autologous chondrocyte transplantation (MACT) for patellar and trochlear lesions. PURPOSE: To document the clinical results of MACT for the treatment of patellar and trochlear chondral defects at long-term follow-up. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 44 patients were prospectively evaluated after MACT for patellofemoral lesions. There were 24 patients affected by patellar lesions, 16 by trochlear lesions, and 4 with both patellar and trochlear defects. Clinical outcomes were analyzed using the International Knee Documentation Committee (IKDC) subjective form, EuroQol visual analog scale, and Tegner score for sport activity level before surgery and at follow-up time points of 5, 10, and a minimum of 15 years (mean final follow-up, 17.6 ± 1.6 years). A Kaplan-Meier survival analysis was performed to examine the survival to failure. Failure was defined as the need for a second surgery because of the persistence of symptoms related to the primary defect. RESULTS: An overall significant improvement was documented from baseline to the last follow-up. The IKDC subjective score improved in the trochlear group from 41.0 ± 13.3 at baseline to 83.9 ± 21.6 at 5 years (P < .005), remaining stable up to the final follow-up (81.3 ± 20.5). In the patellar group, the IKDC subjective score improved from 36.1 ± 14.4 at baseline to 72.3 ± 17.5 at 5 years (P < .005), remaining stable up to the final follow-up (62.0 ± 20.3). Patients with trochlear lesions presented higher IKDC subjective scores compared with those with patellar lesions at 5 (P = .029), 10 (P = .023), and ≥15 years (P = .006) of follow-up. Similar trends were documented for the Tegner score, while no differences were documented for the EuroQol visual analog scale score between patellar and trochlear lesions. There were 4 failures (9.1%) during the follow-up period. The Kaplan-Meier survival analysis did not show statistically significant differences between trochlear and patellar lesions. CONCLUSION: This hyaluronic acid-based MACT technique offered positive and durable clinical outcomes with a low failure rate at long-term follow-up in patients affected by patellofemoral cartilage lesions. However, trochlear and patellar lesions demonstrated a notable difference in terms of clinical findings and sport activity level, with significantly higher results for patients with trochlear lesions but less satisfactory outcomes for patients with patellar lesions.

Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) Scores > 55 at 6 Months Postoperative Predict Ability to Achieve Patient Acceptable Symptomatic State at Minimum 1 Year Postoperative Following Autologous Chondrocyte Implantation for Grade IV Chondral Defects About the Patellofemoral Joint.

PURPOSE: The primary aim is to evaluate the relationship between MOCART scores and patient satisfaction, as evaluated by achievement of (1) the Patient Acceptable Symptomatic State (PASS) and (2) the minimal clinically important difference (MCID) for Knee Injury and Osteoarthritis Score Quality of Life (KOOS QoL), for patients undergoing autologous chondrocyte implantation (ACI) for focal Grade IV patellofemoral chondral defects. The secondary aim is to determine the threshold MOCART score which predicts the ability to meet the PASS and the MCID for KOOS QoL. METHODS: Patients undergoing ACI for grade IV patellofemoral chondral defects by a single surgeon from 2017 to 2020 were identified by search of the EMR. To determine PASS status, patients were asked, "Do you consider your current level of symptoms to be acceptable?" KOOS QoL scores were also collected. Patients with 6-month postoperative knee MRI, PASS scores, and minimum 2-year follow-up data were included. Paired t tests and Wilcoxon Rank-Sum tests were used to evaluate the relationship between MOCART scores and (1) PASS achievement and (2) achievement of the MCID for KOOS QoL (12.8). RESULTS: Thirty-four patients were included, with a median age of 35.1 years [IQR: 24.6, 37.1], and BMI of 24.0 kg/m2 [IQR: 21.5, 28.1]. The median time to postoperative MRI was 6.7 months [IQR: 5.8, 7.9], and average follow-up time was 3.7 ± 1.2 years. Twenty-five patients (74%) achieved PASS, and 18 patients (out of 27 who had postop KOOS QoL Scores, 67%) achieved the MCID for KOOS QoL. Patients who achieved PASS had higher average MOCART scores (61.8 ± 16.0) than those who did not achieve PASS (45.0 ± 12.8, p=0.011), whereas patients who achieved the MCID for KOOS QoL did not have higher MOCART scores than those who did not achieve the MCID (61.9 ± 18.3 versus 53.3 ± 17.1, P = 0.25). There was no relationship between age, sex, lesion size, and lesion location and ability to achieve PASS or MCID for KOOS QoL (p>0.05). A threshold MOCART value of 55 was associated with the highest AUC on ROC analysis for likelihood of achieving PASS (0.778) and MCID for KOOS QoL (0.667). CONCLUSION: Higher MOCART scores are associated with an increased likelihood of achieving PASS following patellofemoral ACI. Moreover, MOCART scores > 55 predict the ability to achieve PASS and the MCID for KOOS QoL following patellofemoral ACI. LEVEL OF EVIDENCE: IV.

Anatomic Risk Factors for Patellofemoral Joint Instability: An Infographic as a Visual Learning Tool.

Patellofemoral instability is a complex pathology with multiple risk factors, which affects mostly young females and may avert them from both activities of daily living and sports participation. Risk factors for instability include patella alta, trochlea dysplasia, abnormal lateral patellar tilt, and increased tibial tuberosity-trochlea groove distance. The knowledge of these anatomical abnormalities is the key to identifying the problem and succeeding in treating the patients.

The importance of interdigitating screw fixation of the trochlea in double plate osteosynthesis of low transcondylar distal humerus fractures: A biomechanical study.

OBJECTIVE: The trochlea is of great importance for the stability of the elbow and its fixation in low transcondylar fractures of the distal humerus is especially challenging. The aim of this study was to determine the optimal trochlea fixation in double plate osteosynthesis of intraarticular distal humerus fractures. METHODS: A low transcondylar, C3-type distal humerus fracture was created in 20 fresh-frozen human cadaveric humeri. The samples were then randomly divided into two groups of 10 specimens each. Double plate osteosynthesis was performed in both groups. In group A, the two most distal screws of the lateral plate were inserted into the trochlea fragment. In group B, these screws did not extend into the trochlea. Displacement under cyclic loading and ultimate failure loads were determined for all specimens. RESULTS: Group A showed significantly less displacement under cyclic loading in each measurement interval (0.92 mm vs. 1.53 mm after 100 cycles, p = 0 0.006; 1.10 mm vs. 1.84 mm after 1000 cycles, p = 0.007; 1.18 mm vs. 1.98 mm after 2000 cycles, p = 0.008). The ultimate failure load was significantly higher in group A than in group B (345.61 ± 120.389 N vs. 238.42 ± 131.61 N, p = 0.037). CONCLUSIONS: Fixation of the trochlea with interdigitating screws in double plate osteosynthesis of low-condylar type C distal humerus fractures results in superior construct stability. LEVEL OF EVIDENCE: not applicable (biomechanical).

Trochlea Dysplasia as the Major Anatomic Risk Factors for Patellofemoral Joint Instability: An Infographic as a Visual Learning Tool.

Patellofemoral instability (PFI) is a common condition in children and adolescents, ranging from mild discomfort and mal-tracking to lateral patellar dislocation [1]. A number of anatomical risk factors have been described in the literature, such as trochlear dysplasia, patella alta, excessive tibial tuberosity to trochlear groove (TT-TG) distance, patellar tilt and soft tissue alterations [2]. Among them, TD has been identified as the main anatomical risk factor with the strongest association with PFI [1, 2]. In the study by Dejour et al. [2] radiographically observed TD was identified in 96% of patients with a history of patellofemoral dislocation [1, 2]. Patients with Dejour Type D dysplasia are characterized by a prominent and convex lateral facet with a vertical connection to a hypoplastic medial facet (Figure 1), which provides inadequate tracking of the patella in the trochlea during flexion leading to patella subluxation [2]. Non-operative treatment of lateral patellar dislocation presents a rate of re-dislocation up to 70% within 24 months of the first episode [3]. Sulcus deepening trochleoplasty is indicated for Type B and D dysplasia, in order to improve patella tracking, reduce the rate of re-dislocation and achieve good functional outcomes [2, 4]. Trochlea dysplasia is defined as a shallow or flattened groove with decreased resistance to lateral patellar translation. TD can be assessed on computed tomography (CT) and magnetic resonance imaging (MRI) with the use of overlapping axial images and are able to show perfectly the global shape of the femoral trochlea [2]. The thresholds for identifying trochlear dysplasia are established based on the sulcus angle ≥ 145°, medial/lateral trochlea facet asymmetry < 40%, trochlear depth < 3 mm and lateral trochlear inclination ≤ 11° and therefore it can be used in young adolescents [4, 5]. A deep knowledge of anatomic variations and abnormalities of the patellofemoral joint, which may predispose to PFI, is crucial in order to choose the appropriate treatment for each patient.

Patello-femoral arthroplasty- indications and contraindications.

Patellofemoral arthroplasty (PFA) is emerging as an attractive alternative to total knee arthroplasty (TKA) for isolated patellofemoral-osteoarthritis (PF-OA) for selected patients. The success of PFA is highly dependent on patient selection. This intervention is still burdened with a higher rate of revisions and a lower survival rate than TKA when the indications or the surgical technique are not optimal. We highlight the indications and contraindications of PFA to obtain satisfying functional outcomes and survivorship. Preoperative clinical and radiological assessment is critical to determine the presence of PFA indications, the absence of contraindications and the necessity of any associated procedures, particularly for the tibial tubercle. The typical indications are patients with isolated symptomatic PF-OA, with trochlear dysplasia, when bone-on-bone Iwano 4 osteoarthritis is observed, without significant malalignment and with the absence of risk factors for developing progressive tibiofemoral-OA. The three main causes of isolated PF-OA are primary OA, trochlear dysplasia and posttraumatic OA following patellar fracture. Trochlear dysplasia is the preferred indication for PFA. Lack of experience with arthroplasty or realignment of the extensor mechanism is a relative contraindication to performing PFA.

A Partial Frontal Fracture of the Humeral Trochlea: A Case Report.

Fractures of the lower end of the humerus are uncommon but serious, potentially compromising elbow function. This article reports the case of a young patient with a fracture of the inner cheek of the humeral trochlea, resulting from a public road accident. The diagnosis was established by radiography and CT scan, confirming a displaced fracture associated with an avulsion fracture of the coronoid process. Surgical treatment was carried out with fixation of the osteochondral fragment and evacuation of the intra-articular fragments. Two months after the operation, the patient regained good joint function with a resumption of professional activity.

Clinical Outcomes and Management Strategies for Capitellum and Trochlea Fractures: A Systematic Review.

Purpose: Capitellum and trochlea fractures, also referred to as coronal shear fractures of the distal humerus, are infrequent yet challenging intra-articular fractures of the elbow. There are a variety of surgical approaches and fixation methods with often variable outcomes. This systematic review investigates interventions, outcomes and complications of capitellum and trochlea fractures. Methods: A systematic review of studies published in MEDLINE, EMBASE, Web of Science and Cumulative Index to Nursing and Allied Health literature (CINAHL) was conducted to assess the clinical outcomes of capitellum and trochlea fractures managed surgically. Data on patient demographics, surgical approach, implant usage, postoperative outcomes and complications were compiled. Results: Forty-one studies met the inclusion criteria with a total of 700 patients. Surgical interventions primarily utilized either the lateral (79%) or antero-lateral (15%) approaches with headless compression screws as the most common fixation method (68%). Clinical outcomes were measured using the Mayo Elbow Performance Index (MEPI) with a mean score of 89.9 (±2.6) and the DASH score with a mean of 16.9 (±7.3). Elbow range of motion showed a mean flexion of 126.3° (±19.4), extension of 5.71° (±11.8), pronation of 75.23° (±12.2), and supination of 76.6° (±9.8). The mean flexion-extension arc was 113.7° (±16.9), and the mean pronation-supination arc was 165.31° (±9.41). Complications occurred in 19.8% of cases, with re-interventions required in 8.3% of cases, mainly due to symptomatic implants and elbow stiffness requiring surgical release. Other complications included implant removal (10.4%), overall reported stiff elbows (6%), nerve palsies (2%), non-union (1.5%), and infection (1.2%). Conclusion: The treatment of capitellum and trochlea fractures yields satisfactory outcomes but has a considerable rate of complications and reoperations primarily due to symptomatic implants and elbow stiffness. There is noteworthy variability in the achieved range of motion, suggesting unpredictable outcomes. Deficits in functionality and range of motion are common after surgery, especially with more complex injury patterns.

A Comparison of Rib Osteochondral Graft to Medial Femoral Trochlear Osteocartilaginous Graft for the Salvage of the Fragmented Scaphoid Proximal Pole: A Single-Center Experience with Minimum 2-Year Follow-Up.

Purpose Fragmented fractures of the proximal pole of the scaphoid that cannot be internally fixed may be salvaged by four-corner arthrodesis or proximal row carpectomy. Replacement of the proximal scaphoid with costal-osteochondral graft (COG) or the medial femoral trochlea (MFT) graft are two alternative solutions for this clinical presentation. The purpose of this study was to compare the clinical and radiographic results of the COG and the MFT graft with a minimum 2-year follow-up from a single centre. Methods A retrospective study was performed to investigate the outcome of COG and MFT with a minimum 2 year follow up. Demographic data and clinical assessment including wrist range of motion and grip strength measurements and Oxford Knee score were collected. Patients completed the outcome measures of Disabilities of Arm, Shoulder, and Hand (DASH), the Patient-Rated Wrist Evaluation (PRWE), and a ten-point visual analogue score for pain (VAS). Radiological examination was performed on all wrists at follow-up. Results The visual analogue score, DASH and PRWE were similar between the two groups. There was radiographic evidence of arthritis between the radial styloid and distal scaphoid in all patients that underwent COG but no evidence in those that underwent MFT graft reconstruction. There were different complications in each group. Thirty percent of patients that underwent MFT reconstruction had persistent knee pain at follow up. Conclusion Though there are notable differences in the follow-up period, patients undergoing MFT risk developing knee pain, while those undergoing COG risk radiographic progression of wrist arthritis. Level of Evidence III - Comparative study.

[Effectiveness of Kirschner wire fixation for proximal phalangeal bone avulsion fracture caused by A2 circular trochlea injury of flexor digitorum tendon].

Objective: To explore the mechanism, surgical method, and effectiveness of proximal phalangeal bone avulsion fracture caused by A2 circular trochlea injury of the flexor digitorum tendon. Methods: A retrospective analysis was conducted on the clinical data of 4 patients with proximal phalangeal bone avulsion fracture caused by A2 circular trochlea injury of flexor digitorum tendon admitted between May 2018 and September 2022. The patients were all male, the age ranged from 26 to 52 years, with an average of 33 years. The injured fingers included 1 case of middle finger and 3 cases of ring finger. The causes of injury were rock climbing of 2 cases and carrying heavy objects of 2 cases. Preoperative anteroposterior and lateral X-ray films and CT examination of the fingers showed a lateral avulsion fracture of the proximal phalanx, with a fracture block length of 15-22 mm and a width of 3-5 mm. The total active range of motion (TAM) of the injured finger before operation was (148.75±10.11)°. The grip strength of the middle and ring fingers was (15.50±2.88) kg, which was significantly lower than that of the healthy side (50.50±7.93) kg ( t=-8.280, P<0.001). The time from injury to operation was 2-7 days, with an average of 3.5 days. One Kirschner wire with a diameter of 1.0 mm was used for direct fixation through the fracture block, while two Kirschner wires with a diameter of 1.0 mm were used for compression fixation against the fracture block. The fracture healing was observed, and the TAM of the injured finger and the grip strength of the middle and ring fingers were measured. The finger function was evaluated according to the upper limb functional assessment trial standards of the Chinese Medical Association Hand Surgery Society. Results: The incisions all healed by first intention after operation. All patients were followed up 6-28 months, with an average of 19 months. X-ray films showed that all avulsion fractures of proximal phalanx reached bony union, and the healing time ranged from 4 to 8 weeks, with an average of 4.6 weeks. At last follow-up, the grip strength of the middle and ring fingers was (50.50±7.76) kg, which significantly improved when compared with preoperative one ( t=-8.440, P<0.001). The TAM of the injured finger reached (265.50±2.08)°, and there was a significant difference when compared with preoperative one ( t=-21.235, P<0.001). According to the upper limb functional assessment trial standards of the Chinese Medical Association Hand Surgery Society, the finger function was all evaluated as excellent in 4 cases. Conclusion: Using Kirschner wire fixation through bone blocks and external compression fixation of bone blocks for treating proximal phalangeal bone avulsion fracture caused by A2 circular trochlear injury of the flexor digitorum tendon can achieve good effectiveness.

The Number of Patellar Dislocation Events Is Associated With Increased Chondral Damage of the Trochlea.

BACKGROUND: Patellofemoral instability is associated with chondral injuries to the patella, trochlea, and lateral femoral condyle. Although studies have demonstrated an association between patellar dislocations and chondral injuries, the influence of the number of dislocations on chondrosis is not established. PURPOSE: To elucidate the precise association between the number of patellar dislocation events and the severity of chondral injuries in a multicenter cohort study at the time of patellar stabilization procedures. STUDY DESIGN: Cross-sectional study; Level of evidence, 2. METHODS: A prospective multicenter cohort study (JUPITER [Justifying Patellar Instability Treatment by Early Results]) database was queried for cases of primary patellofemoral instability procedures from December 2016 to September 2022. Cartilage lesions were classified using the International Cartilage Repair Society (ICRS) classification system during an arthroscopic or open evaluation (direct visualization), with grades 2 to 4 considered abnormal. The number of dislocations was categorized as 1, 2-5, and >5. Categorical variables were compared with the chi-square test, and binary logistic regression was performed to identify predictors of the presence of chondral lesions. RESULTS: A total of 938 knees (mean age, 16.2 ± 3.8 years; 61.4% female) were included, with 580 (61.8%) demonstrating a chondral injury. The most affected region was the patella (n = 498 [53.1%]), followed by the lateral femoral condyle (n = 117 [12.5%]) and trochlea (n = 109 [11.6%]). There were no differences in the presence (P = .17) or grade (P = .63) of patellar lesions by the number of dislocations. Patients with >5 dislocations more frequently had trochlear chondral lesions (19.8%) compared with those with fewer dislocations (1, 7.6%; 2-5, 11.0%; P < .001). More dislocations were also associated with a higher proportion of ICRS grade 2 to 4 trochlear lesions (>5, 15.3%; 2-5, 10.0%; 1, 6.9%; P = .015). Combined patellar and trochlear lesions were also more common in those with >5 dislocations (P = .001). In multivariable regression, >5 dislocations was the only variable predictive of a trochlear lesion (odds ratio, 3.03 [95% CI, 1.65-5.58]; P < .001). CONCLUSION: This large prospective cohort study demonstrated that recurrent patellar dislocations can lead to more severe chondral damage in specific locations in the knee. More than 5 dislocations was associated with a >3-fold increase in the incidence and severity of trochlear chondral injuries. There were no differences in the presence or grade of patellar lesions by the number of dislocations. These findings should caution surgeons regarding prolonged nonoperative treatment.