Avoiding screw overlength using dorsal horizon view in palmar plate osteosynthesis of distal radius fractures: a prospective randomized trial.

INTRODUCTION: Distal radius fractures are the most commonly reported fractures in adults. Treatment has changed in recent years to open reduction and palmar plate fixation. Penetration of the dorsal screw, however, is a well-known complication. Intraoperative anteroposterior and lateral radiographs lack the exact assessment of dorsal screw length and intraoperative measurement is therefore very likely to be inaccurate in a comminuted dorsal radial cortex. Secondary extensor tendon ruptures are reported in up to 6% following palmar plate fixation of distal radius fracture. MATERIALS AND METHODS: A prospective randomized trial was performed to assess the value of the dorsal horizon view. The hypothesis was that the traditional anteroposterior and lateral fluoroscopic views aided by an axial view of the dorsal part of the radius, named dorsal horizon view, could prevent dorsal screw penetration. A total of 40 patients, 6 male and 34 female, were included in the study. Standardized anteroposterior and lateral radiographs were performed intraoperatively in 18 patients (standard group = control group). In 22 patients, intraoperative axial fluoroscopic views (dorsal horizon view) were added to anteroposterior and lateral images (horizon group). Numbers of intraoperative screw changes due to the two different radiological examinations were analyzed as well as exact postoperative CT guided measurement of screw length. RESULTS: The total numbers of intraoperative screw changes were significantly higher in the horizon group. Forty-two screws were changed in 15 patients in the horizon group while only 8 screws were changed in 3 patients in the standard group. Postoperative computed tomography scans showed significantly lower total numbers of perforating screws in the horizon group with 11 screws in 22 patients compared to 20 screws in 18 patients in the standard group (p = 0.02). CONCLUSIONS: Based on the results of this study, the dorsal horizon view improves the assessment of the correct screw length and should routinely be used in palmar plate osteosynthesis of distal radius fractures. Since screw protrusion cannot be absolutely ruled out using the dorsal horizon view, monocortical drilling or screw downsizing is still mandatory. TRIAL REGISTRATION: This clinical trial was not registered because it was a clinical examination without any experimental techniques.

Transpatellar bone tunnels perforating the lateral or anterior cortex increase the risk of patellar fracture in MPFL reconstruction: a finite element analysis and survey of the International Patellofemoral Study Group.

PURPOSE: (1) To determine applied patellar drilling techniques for medial patellofemoral ligament (MPFL) reconstruction among members of the International Patellofemoral Study Group (IPSG) and (2) to evaluate the risk of patellar fracture for various patellar bone tunnel locations based on a finite element analysis (FEA) model. METHODS: In the first part of the study, an online survey on current MPFL reconstruction techniques was conducted among members of the IPSG. In the second part of the study, a three-dimensional FEA model of a healthy knee joint was created using a computed tomography scan. Patient-specific bone density was integrated into the patella, and cartilage of 3 mm thickness was modeled for the patellofemoral joint. According to the survey's results, two different types of patellar bone tunnels (bone socket and transpatellar bone tunnel) were simulated. The risk of patellar fracture was evaluated based on the fracture risk volume (FRV) obtained from the FEA. RESULTS: Finite element analysis revealed that subchondral bone socket tunnel placement is associated with the lowest FRV but increased with an anterior offset (1-5 mm). Transpatellar bone tunnels violating the lateral or anterior cortex showed a higher FRV compared to bone socket, with the highest values observed when the anterior cortex was penetrated. CONCLUSION: Violation of the anterior or lateral patellar cortex using transpatellar bone tunnels increased FRV compared to a subchondral patellar bone socket tunnel. In MPFL reconstruction, subchondral patellar bone socket tunnels should be considered for patellar graft fixation to avoid the risk of postoperative patellar fracture. LEVEL OF EVIDENCE: Survey; Descriptive laboratory study/Level V.

The superficial medial collateral ligament is the major restraint to anteromedial instability of the knee.

PURPOSE: The purpose of the present study was to determine how the medial structures and ACL contribute to restraining anteromedial instability of the knee. METHODS: Twenty-eight paired, fresh-frozen human cadaveric knees were tested in a six-degree of freedom robotic setup. After sequentially cutting the dMCL, sMCL, POL and ACL in four different cutting orders, the following simulated clinical laxity tests were applied at 0°, 30°, 60° and 90° of knee flexion: 4 Nm external tibial rotation (ER), 4 Nm internal tibial rotation (IR), 8 Nm valgus rotation (VR) and anteromedial rotation (AMR)-combined 89 N anterior tibial translation and 4 Nm ER. Knee kinematics were recorded in the intact state and after each cut using an optical tracking system. Differences in medial compartment translation (AMT) and tibial rotation (AMR, ER, IR, VR) from the intact state were then analyzed. RESULTS: The sMCL was the most important restraint to AMR, ER and VR at all flexion angles. Release of the proximal tibial attachment of the sMCL caused no significant increase in laxity if the distal sMCL attachment remained intact. The dMCL was a minor restraint to AMT and ER. The POL controlled IR and was a minor restraint to AMT and ER near extension. The ACL contributed with the sMCL in restraining AMT and was a secondary restraint to ER and VR in the MCL deficient knee. CONCLUSION: The sMCL appears to be the most important restraint to anteromedial instability; the dMCL and POL play more minor roles. Based on the present data a new classification of anteromedial instability is proposed, which may support clinical examination and treatment decision. In higher grades of anteromedial instability an injury to the sMCL should be suspected and addressed if treated surgically.

Sonographic evaluation of lateral meniscal extrusion: implementation and validation.

INTRODUCTION: Meniscal extrusion (ME) is an important indicator of and prognostic factor for various knee pathologies. To date, no standardized protocol for the ultrasound-based examination of lateral ME exists. The purpose of the present study was to test the reliability and validity of lateral ME measurements using a standardized ultrasound-based examination protocol. MATERIALS AND METHODS: A group consisting of 11 healthy volunteers (Group I, male and female, 18-45 years) as well as a group of 10 consecutive patients who had undergone all-inside lateral meniscal radial tear repair were included (Group II, male and female, 23-43 years). Lateral ME, the main outcome parameter, was measured by ultrasound (US; both groups) and magnetic resonance imaging (MRI; Group II only). Both knees of all subjects were examined in an unloaded state and under axial compression of the knee (50% of body weight). Repeated measurements obtained in Group I by 2 observers were used for reliability testing, and the validity of US was assessed through comparison with MRI data (Group II). RESULTS: A total of 66 US images of Group I, obtained by each observer, were analyzed for reliability testing. Forty US and MR images of Group II were assessed for validation. Results showed good interrater (ICC = 0.904) and excellent intrarater (ICC = 0.942) reliability of US-based measurements of lateral ME. Agreement with MRI results was poor (ICC = 0.439), with US systematically overestimating results by 1.1 mm on average. CONCLUSIONS: Ultrasound is a reliable, quick and cost-effective technique for lateral ME measurement, but results are not readily comparable with MRI. TRIAL REGISTRATION: The study was registered in the European Union Clinical Trials Register (EudraCT-Number: 2017-005037-24).

Non-operative treatment of ACL injury is associated with opposing subjective and objective outcomes over 20 years of follow-up.

PURPOSE: The aim of this study was the evaluation of long-term clinical and radiological outcomes of non-operative treatment of anterior cruciate ligament (ACL) deficiency. The hypothesis was that conservative treatment would be associated with a deterioration of subjective and objective measures of joint health and disability over time. METHODS: From an initial sample of 41 patients conservatively treated for ACL rupture, 10 received secondary ACL reconstruction, 1 was excluded due to contralateral ACL injury, and 1 patient required total knee replacement and a high tibial osteotomy. Seven further patients were lost to follow-up. The remaining 21 patients (15 male, 6 female, mean age 53.1 ± 9.2 years at the last follow-up) were evaluated by the same two examiners 5-7, 10-13 and 20-22 years after the injury. The evaluation was based on objective and subjective scores, instrumented testing, radiographic examination and assessment of sports activity. RESULTS: While subjective patient satisfaction improved over time, objective scores stayed constant or deteriorated (radiologic evaluation). Instrumented knee laxity testing showed an initial tendency to increasing instability, followed by a decrease in anterior tibial translation in the second half of the observation period. Physical activity levels, particularly in high-risk sports, decreased significantly (p < 0.05) compared to preinjury levels. All patients developed significant arthritic degenerative changes over time compared to the uninjured contralateral knee. No correlation to activities in high- or low-risk pivoting sports was found. CONCLUSIONS: Patient satisfaction with conservative treatment of ACL injuries is good in spite of objective measures indicating increasing degenerative changes. LEVEL OF EVIDENCE: IV.

Medial patellofemoral ligament (MPFL) reconstruction using quadriceps tendon autograft provides good clinical, functional and patient-reported outcome measurements (PROM): a 2-year prospective study.

PURPOSE: The medial patellofemoral ligament (MPFL) is the most important ligamentous stabilizer preventing lateral patella dislocation. Numerous surgical procedures for MPFL reconstruction have been described in the literature. The aim of this study was to investigate the clinical, functional and patient-reported (PROM) outcomes 2 years after minimally invasive MPFL reconstruction performed using an autologous strip of the quadriceps tendon. METHODS: Thirty-six patients (38 knees) were included in the study. For MPFL reconstruction, a partial thickness autologous quadriceps tendon graft was used. All patients were evaluated clinically and with patient-reported outcome questionnaires including the Tegner, Lysholm and Kujala scores as well as a visual analogue scale (VAS) for pain preoperatively and at 6, 12 and 24 months postoperatively. A functional Back-in-Action (BIA) test battery, including a total of seven stability, agility and jumping tests, was performed on 19 (50%) patients at the final follow-up. One patient was lost to follow-up at 24 months. RESULTS: The mean age at the time of operation was 25.2 ± 6.1 years. No redislocations occurred during the period of investigation. The mean Lysholm score improved significantly from 79.3 ± 16.1 preoperatively to 83.2 ± 14.4 at 6 months, 88.1 ± 11.3 at 12 months and to 90.0 ± 9.6 at 24 months follow-up. No change throughout the study period was observed for the median Tegner Activity Score (median 6). The mean Kujala score increased from a preoperative value of 82.0 ± 12.4, to 84.5 ± 8.4 at 6 months, and 88.2 ± 5.8 at 12 months up to 88.7 ± 4.5 at 24 months follow-up. A total of 77.8% of the performed functional BIA tests were equal to or above the norm for patients of the corresponding ages and activity levels. CONCLUSIONS: Minimally invasive MPFL reconstruction with a partial thickness strip of quadriceps tendon is a safe and effective treatment for patellofemoral instability. Good clinical, functional and subjective results were observed at the 2-year follow-up. LEVEL OF EVIDENCE: Prospective cohort study, non-randomized, Level IV.

Neer Award 2019: Latarjet procedure vs. iliac crest bone graft transfer for treatment of anterior shoulder instability with glenoid bone loss: a prospective randomized trial.

BACKGROUND: The Latarjet and iliac crest bone graft transfer (ICBGT) procedures are competing treatment options for anterior shoulder instability with glenoid bone loss. METHODS: In this bicentric prospective randomized study, 60 patients with anterior shoulder instability and glenoid bone loss were included and randomized to either an open Latarjet or open ICBGT (J-bone graft) procedure. Clinical evaluation was completed before surgery and 6, 12, and 24 months after surgery, including the Western Ontario Shoulder Instability index, Rowe score, Subjective Shoulder Value, pain level, satisfaction level, and work and sports impairment, as well as assessment of instability, range of motion, and strength. Adverse events were prospectively recorded. Radiographic evaluation included preoperative, postoperative, and follow-up computed tomography analysis. RESULTS: None of the clinical scores showed a significant difference between the 2 groups (P > .05). Strength and range of motion showed no significant differences except for diminished internal rotation capacity in the Latarjet group at every follow-up time point (P < .05). A single postoperative traumatic subluxation event occurred in 2 ICBGT patients and 1 Latarjet patient. The type and severity of other adverse events were heterogeneous. Donor-site sensory disturbances were observed in 27% of the ICBGT patients. Computed tomography scans revealed a larger glenoid augmentation effect of the ICBGTs; this, however, was attenuated at follow-up. CONCLUSION: The Latarjet and ICBGT procedures for the treatment of anterior shoulder instability with glenoid bone loss showed no difference in clinical and radiologic outcomes except for significantly worse internal rotation capacity in the Latarjet group and frequently noted donor-site sensory disturbances in the ICBGT group.

Glenoid morphology is associated with the development of instability arthropathy.

BACKGROUND: Instability arthropathy (IA) is a major long-term concern in patients with anterior shoulder instability. This study investigated the association of glenoid morphology with the development of IA. METHODS: The study included 118 patients with unilateral anterior shoulder instability and available bilateral computed tomography scans. Instability-specific information was obtained from all patients. The glenoid morphology of the affected shoulder was compared with the nonaffected contralateral side resembling the constitutional preinjury glenoid shape. Both shoulders were evaluated independently by 3 observers to assess the grade of IA according to a Comprehensive Arthropathy Rating (CAR) system. Associations between IA and the glenoid morphology parameters were investigated. RESULTS: The average glenoid retroversion (P < .001), glenoid depth (P < .001), glenoid diameter (P < .001), and the bony shoulder stability ratio (P < .001) of the affected shoulder were significantly reduced compared with the contralateral side due to bony defects in 79.6% of the patients. The CAR of the affected side was significantly higher (P < .001), with more osteophytes (P = .001) and more sclerosis and cysts (P < .001). Differences in CAR (Δ-CAR) correlated positively with the age at the time of the computed tomography scan (P < .001), age at the initial dislocation (P = .001), size of the glenoid defect (P = .005), and the contralateral glenoid depth (P = .011), glenoid diameter (P = .016), and bony shoulder stability (P = .029), and negatively with glenoid retroversion of the affected side (P = .027). CONCLUSION: Development of IA arthropathy is associated not only with the age of the patients but also with morphologic parameters of the glenoid, including glenoid defect size and the constitutional glenoid concavity shape.

What is the chance that a patella dislocation will happen a second time: update on the natural history of a first time patella dislocation in the adolescent.

PURPOSE OF REVIEW: Patellar instability occurs mainly in young patients and shows a high incidence of concomitant cartilage injuries. Recently there has been a strong attempt to identify risk factors and enhance imaging techniques to detect patients with an increased risk for recurrent patella dislocation.We describe current findings on factors associated with recurrent patella dislocation in the adolescent. RECENT FINDINGS: Trochlear dysplasia, patellar height, patellar tilt, tibial tuberosity-trochlear groove distance, skeletal maturity, and history of contralateral patellar dislocation are well known significant risk factors for recurrence in adolescent patients. Predictive models to calculate risk of recurrence have been reported recently. The Patellar Instability Severity Score was the first to include demographic and anatomic factors, which is of major value when counseling patients and relatives. SUMMARY: Several classification systems to predict the rate of recurrence after primary patella dislocation have been presented over the last years. Anatomic risk factors such as skeletal immaturity, trochlear morphology, patellar height, patellar tilt, and elevated tibial tuberosity-trochlear groove distance have been investigated. However, there is still a lack of knowledge as to how single risk factors or their interaction with each other may contribute.

There is no difference between quadriceps- and hamstring tendon autografts in primary anterior cruciate ligament reconstruction: a 2-year patient-reported outcome study.

PURPOSE: Graft choice for anterior cruciate ligament (ACL) reconstruction is crucial, however the optimal graft source remains a topic of controversy. The purpose of this study is to compare subjective and functional patient-reported outcomes (PRO) after single-bundle ACL reconstruction using quadriceps tendon (QT) or hamstring tendon (HT) autografts for single-bundle ACL reconstruction. We hypothesize that there is no difference in patient-reported functional outcomes after ACL reconstruction using either HT- or QT autograft. METHODS: All data were extracted from a prospectively collected ACL registry. A total of 80 patients with at least 2-year follow-up were included in this study. A total of 40 patients with primary ACL reconstruction using a QT autograft harvested via a minimally invasive technique were matched by sex, age and pre-injury Tegner and Lysholm score to 40 patients who received HT autografts. Subjective and functional PRO scores including Lysholm score, Tegner activity level and visual analogue scale for pain were obtained at 6, 12 and 24 months after index surgery. RESULTS: No significant difference between the QT and the HT group was seen at any follow-up in regard to any of the PRO scores for function or pain. 24 months post-surgery the mean Tegner activity score of the HT group was significantly (p = 0.04) lower compared to the pre-injury status. At final follow-up, 27 patients (67.5%) in the QT group and 32 patients (80.0%) in the HT returned to their pre-injury activity level (n.s.). A total of 37 patients (92.5%) of the QT cohort and 35 patients (87.5%) of the HT cohort reported "good" or "excellent" results according to the Lysholm score (n.s.). "No pain" or "slight pain" during severe exertion was reported by 33 patients (82.5%) with QT autograft and 28 patients (82.4%) with HT autograft (n.s.). CONCLUSION: There is no significant difference between PRO 2 years post-operative using either QT or HT autografts. Both QT and HT grafts show acceptable and comparable PRO scores making the QT a reliable graft alternative to HT for primary ACL reconstruction. LEVEL OF EVIDENCE: III.

Acute ACL reconstruction in patients over 40 years of age.

PURPOSE: The purpose of this study is to compare the clinical outcome of ACL reconstructions in patients older than 40 years of age to younger subjects. It has been hypothesized that patients older than 40 years of age achieve comparable clinical outcomes following acute ACL reconstruction using a hamstring tendon autograft than younger patients. METHODS: Patients with an isolated ACL tear without any concomitant injuries and subsequent ACL reconstruction within 48 h from injury were included in this prospective study. According to patients' age, subjects were assigned to two groups: (A) 18-40 years and (B) 40-60 years. Functional outcomes, pain, post-operative radiographs and return to sports were recorded and analysed. The follow-up period was 24 months. RESULTS: A total of 59 patients were included in the study. Group A consisted of 39 patients (14 women, 25 men; median 27 years), group B of 20 patients (12 women, 8 men; median 45 years) respectively. At final follow-up, the Lysholm score showed no significant difference between group A (median 90; range 68-100) and group B (median 94.5; range 63-100) (n.s.). The final Tegner score showed a significant difference between group A (median 6; range 2-9) and group B (median 5.5; range 3-8) (p < 0.05). The mean VAS pain score was 1.3 (range 0-6) in group A and 1 (range 0-7) in group B, respectively (n.s.). Both groups returned to their pre-injury activity level and did not significantly change their activity in respect of pivoting sports and sports frequency at final follow-up (n.s.). According to the IKDC score, all except one of the patients in group A and all patients in group B had a normal or nearly normal final outcome (n.s.). CONCLUSION: Patients older than 40 years of age achieve comparable clinical outcomes following acute ACL reconstruction using a hamstring tendon autograft than younger patients. LEVEL OF EVIDENCE: Cohort study, Level III.

Trilogy of isolated deep medial collateral ligament injuries of the knee: A set of three cases and overview of the literature.

The authors present three unique cases of isolated deep medial collateral ligament (dMCL) injuries and comprehensively review the current literature. An isolated dMCL injury is often overlooked in clinical practice, and a consensus on the most adequate treatment is needed. Three male patients were examined at our institution directly following the trauma. The first patient experienced isolated soft-tissue avulsion of the dMCL, the second patient had a bony avulsion from the femoral insertion of the dMCL, and the third patient presented with an isolated "reverse Segond" fracture, which has not previously been described in the literature. All three injuries resulted from a violent external knee joint rotation. The treatment regime included a knee brace for up to 5 weeks and a physical therapy regimen for up to 3 months. All three patients reported satisfactory outcomes regarding restored knee function, absence of symptoms, and early return to activities at the final follow-up. STUDY DESIGN: Case report. LEVEL OF EVIDENCE: IV.

Peroneus Longus Split Versus Semitendinosus Tendon Autograft Size: A Cross-sectional Study.

BACKGROUND: The anterior half of the peroneus longus tendon (AHPLT) has been reported to be a suitable autograft for ligament reconstruction with low donor-site morbidity. However, clinical data on graft size are limited. PURPOSE: To determine (1) if there is any difference in size between the AHPLT and semitendinosus tendon (ST) and (2) whether anthropometric measurements can predict autograft size. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A total of 128 consecutive patients scheduled for knee ligament reconstruction were prospectively enrolled. Patients were treated with AHPLT (50%) or ST (50%). Data included anthropometric measurements and intraoperatively recorded graft size. A Student t test was used to determine differences between the groups. Bivariate correlation coefficients and multivariate regression analyses were calculated to identify relationships between graft size and anthropometric measurements. RESULTS: The AHPLT and ST groups were equally distributed according to age, sex, height, weight, and body mass index (BMI). The quadrupled graft length for the AHPLT was 7.3 ± 0.6 cm as compared with 7.5 ± 0.7 cm for the ST (P < .05). The quadrupled graft diameter was 7.7 ± 0.8 mm for the AHPLT and 8.0 ± 0.7 mm for the ST (P < .05). Height had a moderate (r = 0.57) to high (r = 0.68) correlation with AHPLT and ST length, respectively (P < .01). Weight had a moderate correlation (r = 0.43) with AHPLT diameter (P < .01) but only a weak correlation (r = 0.19) with ST diameter (P > .05). A significant interaction effect of BMI and thigh circumference on ST graft diameter was found, which showed that the effect of thigh circumference on ST graft diameter decreased significantly as BMI increased (P < .05). This moderating effect of BMI could not be observed for the coefficient of shank circumference on AHPLT graft diameter (P > .05). CONCLUSION: (1) The peroneus longus split tendon provides a reliable autograft size for knee ligament reconstructions. It was prone to be slightly shorter and thinner than the ST. (2) Patient height was the strongest predictor for AHPLT and ST graft length. However, predicting graft diameter based on thigh or shank circumference was more challenging, with higher BMIs affecting the ability to predict ST more than AHPLT.

Medial Collateral Ligament Reconstruction: A Gracilis Tenodesis for Anteromedial Knee Instability.

The main principle of the present medial collateral ligament reconstruction technique is to address anteromedial knee instability. Therefore, we describe a gracilis tenodesis with 2 functional bundles to reconstruct the deep and superficial medial collateral ligament. The proposed technique may be performed as an isolated or combined procedure with anterior cruciate ligament reconstruction. Valgus instability in extension is a contraindication.

Functional and Radiological Outcomes after Treatment with Custom-Made Glenoid Components in Revision Reverse Shoulder Arthroplasty.

Glenoid implant position and fixation are challenging in severe glenoid defects in reverse total shoulder arthroplasty (rTSA). Custom-made glenoid implants are metal augmented implants that are specially produced for a certain defect. They provide the restoration of the joint line and proper fixation. This retrospective data analysis investigated the clinical and radiological outcomes after revision using custom-made glenoid implants. Between 2018 and 2020, nine patients (10 shoulders) with severe glenoid defects underwent revision rTSA using a custom-made glenoid implant (Materialise Glenius or Lima ProMade). The pre- and postoperative Constant Murley Score (CMS), UCLA Score and Subjective Shoulder Value (SSV) were assessed. Postoperative CT scans and X-rays in two planes were available. The minimum follow-up was 12 months, with a mean follow-up of 23.1 months. The mean preoperative CMS, UCLA Score and SSV were 10.9, 4.1 and 11.0, respectively. The mean postoperative CMS, UCLA Score and SSV showed significant increases of 51.7 (<0.001), 22.9 (<0.001) and 52.0 (<0.001), respectively. There were no signs of loosening implants or scapular notching, and no revision was necessary. This trial showed promising clinical and radiological short-term outcomes for custom-made glenoid components in revision rTSA.

MCL Reconstruction Using a Flat Tendon Graft for Anteromedial and Posteromedial Instability.

The main principles of the present medial collateral ligament (MCL) reconstruction techniques are (1) to approximate the natural anatomy and (2) to restore the main passive restraining structures in anteromedial and posteromedial knee instability. Therefore, we describe a technique using a flat tendon graft instead of tubular grafts with point-to-point bone fixation. Moreover, we address the deep MCL, a relevant restraint to anteromedial instability.

The Patellar Instability Probability Calculator: A Multivariate-Based Model to Predict the Individual Risk of Recurrent Lateral Patellar Dislocation.

BACKGROUND: Predicting the risk of recurrence is of great interest when counseling patients after primary lateral patellar dislocation (LPD). PURPOSE: To investigate a multivariate model to predict the individual risk of recurrent LPD. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: The study population included patients with primary LPD, knee imaging, and a minimum 2-year follow-up after nonoperative treatment. Data including patient characteristics and anatomic patellar instability risk factors were collected retrospectively from 7 national study centers. Bivariate and multivariate regression analyses were carried out to identify risk factors for recurrent LPD and to generate an accuracy-optimized model for out-of-sample prediction. RESULTS: In total, 115 of 201 patients (57%) experienced recurrent LPD within 2 years after primary LPD. Age ≤16 years at primary LPD (odds ratio [OR], 5.0), history of contralateral instability (OR, 2.4), and trochlear dysplasia (Dejour type B-D: OR, 2.5; lateral trochlear inclination ≤12°: OR, 2.7) were significant risk factors for recurrent LPD (P < .05). The prediction accuracy including these 3 risk factors was 79%. Patella alta, an increased tibial tubercle to trochlear groove distance, and patellar tilt had neither an association with increased recurrence rates nor an influence on prediction accuracy of recurrent LPD. CONCLUSION: Young age and trochlear dysplasia are major risk factors for early recurrent LPD. A multivariate model including age at primary LPD, lateral trochlear inclination, and history of contralateral LPD achieved the highest prediction accuracy. Based on these findings, the patellar instability probability calculator is proposed to estimate the individual risk of early recurrence when counseling patients after primary LPD.

Graft Survivorship After Anterior Cruciate Ligament Reconstruction Based on Tibial Slope.

BACKGROUND: Increased tibial slope (TS) is believed to be a risk factor for anterior cruciate ligament (ACL) tears. Increased TS may also promote graft insufficiency after ACL reconstruction. PURPOSE: To delineate the relationship between TS and single as well as multiple graft insufficiencies after ACL reconstruction. STUDY DESIGN: Cohort study; Level of evidence 3. METHODS: We retrospectively identified 519 patients who had sustained ACL graft insufficiency after primary or revision ACL reconstruction (1 graft insufficiency, group A; 2 graft insufficiencies, group B; and ≥3 graft insufficiencies, group C). In addition, a subgroup analysis was conducted in 63 patients who received all surgical interventions by 2 specialized high-volume, single-center ACL surgeons. TS was measured by an observer with >10 years of training using lateral knee radiographs, and intrarater reliability was performed. Multiple logistic and univariate Cox regression was used to assess the contribution of covariates (TS, age, sex, and bilateral ACL injury) on repeated graft insufficiency and graft survival. RESULTS: The study included 347 patients, 119 female and 228 male, who were 24 ± 9 years of age at their first surgery (group A, n = 260; group B, n = 62; group C, n = 25). Mean TS was 9.8°± 2.7° (range, 3°-18°). TS produced the highest adjusted odds ratio (1.73) of all covariates for repeated graft insufficiency. A significant correlation was found between TS and the number of graft insufficiencies (r = 0.48; P < .0001). TS was significantly lower in group A (9.0°± 2.3°) compared with group B (12.1°± 2.5°; P < .0001) and group C (12.0°± 2.6°; P < .0001). A significant correlation was seen between the TS and age at index ACL tear (r = -0.12; P = .02) as well as time to graft insufficiency (r = -0.12; P = .02). A TS ≥12° had an odds ratio of 11.6 for repeated ACL graft insufficiency. CONCLUSION: The current results indicate that patients with a markedly increased TS were at risk of early and repeated graft insufficiency after ACL reconstruction. Because the TS is rarely accounted for in primary and revision ACLR, isolated soft tissue procedures only incompletely address recurrent graft insufficiency in this subset of patients.

Fate of the lateral femoral notch following early anterior cruciate ligament reconstruction.

BACKGROUND: The goal of this longitudinal study was to investigate the fate of the lateral femoral notch (LFN), which is frequently seen as an impaction fracture of the lateral femoral condyle in patients with anterior cruciate ligament (ACL) tears. METHODS: Patients who underwent early ACL reconstruction between 2006 and 2010 were reviewed. If post-injury magnetic resonance images showed an LFN greater than 1.5 mm in depth, patients with untreated LFN were followed. Two blinded observers performed quantitative and qualitative imaging analysis. RESULTS: Sixteen patients (five women, 11 men) were available for follow-up nine years (six to 10 years) post-injury. The median defect area of the LFN significantly decreased from 2.3 cm2 (range: 0.9-3.8 cm2) to 1.6 cm2 (range: 0.4-3.2 cm2) (P < .001). The defect depth did not significantly change from 2.3 mm (range: 2.0-3.6 mm) to 2.5 mm (range: 1.3-3.6 mm) (P > .05). The International Cartilage Repair Society (ICRS) score increased from 1.5 (range: 0-3) post-injury to 2.0 (range: 0-4) at follow-up (P < .01). The Lysholm score was 93 (72-100), the Tegner activity level was 6 (3-9) and the knee injury and osteoarthritis outcome score (KOOS) score was 97 (91-100). CONCLUSIONS: The defect area of the LFN decreased overtime, whereas the depth of the impression remained. Focal cartilage lesions were found in all except two patients post-injury and progressed during follow-up. However, patient-reported outcome scores were satisfying.