Patellar Instability Patients Research Articles

No secondary osteoarthritis after recession wedge trochleoplasty associated with tibial tubercle osteotomy for treating recurrent patellar dislocation in high-grade dysplasia.

To determine in the long-term the rate of osteoarthritis of recession wedge trochleoplasty performed in patients with high-grade trochlear dysplasia and recurrent patellar dislocations. The hypothesis was that the rate of secondary osteoarthritis was low. Fifteen consecutive patients (17 knees) undergoing a recession wedge trochleoplasty surgery for recurrent patellar dislocation were retrospectively included. Recurrence of dislocation and functional scores of Lille and Kujala were collected. A complete radiological assessment was carried out to assess secondary patella-femoral and femoro-tibial osteoarthritis. No recurrence of dislocation was observed. Mean Lille and Kujala scores were respectively 84 ± 9/100 and 78 ± 12/100 at an average follow-up of 11.2 ± 1.8 years (132 ± 22 months, range 96-165). No significant radiological changes in osteoarthritis were observed. Of the 15 knees without any radiological signs of patellofemoral osteoarthritis at time of surgery, 7 presented a bone remodeling (Iwano1) and 8 had no signs of osteoarthritis at the latest follow-up. Among the 2 knees with a preoperative Iwano stage 1, one evolved to Iwano stage 2. Recession wedge trochleoplasty is an effective treatment for recurrent patellar instability in patients with a high-grade trochlear dysplasia. In the long term, the patellofemoral joint is stable, the functional scores are good, and there is no significant arthritic degeneration. IV, retrospective series.

Lateral Opening Distal Femoral Osteotomy with Concomitant MPFL Reconstruction is Efficacious in Addressing Patellar Instability.

To describe the clinical and radiographic outcomes of patients undergoing a lateral opening distal femur osteotomy (DFO) to address valgus alignment and restore patellar stability. A retrospective review of patients who underwent lateral opening DFO for recurrent patellar instability in the setting of valgus leg alignment at a single academic institution between January 2016 to December 2021 was performed. Patients without a minimum 24-month postoperative follow-up were excluded. Rates of recurrent patellar instability, patient-reported outcomes, and complications were assessed. Pre- and post-operative radiographic anatomic lateral distal femoral angle (aLDFA) was evaluated to assess alignment correction. 20 lateral opening DFO cases were included from 15 patients [mean age 19.6 years, mean follow-up 42.4 months (range 24-63 months)]. 19 of 20 (95.0%) knees experienced no recurrent patellar dislocation. 13 of 20 (65.0%) knees underwent re-operation [hardware removal (n = 10); revision stabilization procedure (n = 1); lysis of adhesions and manipulation under anesthesia (LOA/MUA) (n = 1); nonunion revision with bone grafting (n = 1). mLDFA significantly changed from 86.3 degrees preoperatively to 91.4 degrees postoperatively (p < 0.001). Mean aLDFA changed significantly from 77.4 preoperatively to 84.4 degrees postoperatively (p < 0.001). The final Kujala score had a median value of 92 (IQR 85.5 - 98), Lysholm score was 90 (IQR 76 - 95), and Tegner score was 5 (IQR 4 - 7). Lateral opening DFO is an efficacious procedure to address recurrent patellar instability in patients with valgus leg alignment. The present retrospective case series demonstrates good functional outcomes and low rates of recurrent instability and major complications after a lateral opening DFO, despite a large proportion of patients having undergone previous surgery. There were relatively high rates of reoperation and hardware irritation. Retrospective case series; Level of evidence, 4.

Turkish Version of the Norwich Patellar Instability Score: Minimal Detectable Change among Patients with Traumatic Patellar Dislocation

Objective: This study aimed to calculate the minimal detectable change (MDC) in the Norwich Patellar Instability score (NPI) and validate the score for Turkish-speaking individuals with patellar instability. Method: Sixty-four patients (mean age 21.87 ± 9.44 years) who had experienced at least one patellar dislocation during athletic activities participated in the study. The Turkish version of the NPI (NPI-T) was evaluated for reliability and internal consistency. The Minimal Detectable Change was calculated as an overall value for the participants. MDC was calculated based on the standard error of measurement (SEM) and the selected confidence level (ICC) for the study population. Pearson's correlations were examined to assess construct validity between the Kujala Patellofemoral Disorder score and the Lysholm Knee Score. Result: The MDC for the NPI-T was 17.29, with a SEM of 6.24. The score demonstrated high internal consistency, with a Cronbach’s alpha value of 0.85, indicating substantial reliability. The consistency of measurements was excellent, with an ICC2,1 of 0.95. Additionally, the NPI-T score exhibited a strong negative correlation with both the Kujala (r = -0.85, p &lt; 0.001) and Lysholm (r = -0.89, p &lt; 0.001) scores. A floor effect was observed, but no ceiling effect was present. Conclusion: The study confirms that the NPI-T demonstrates strong psychometric properties, with high internal consistency and excellent reliability, as evidenced by its low MDC and SEM. The use of the NPI-T as a reliable and valid tool for assessing patellar instability in patients with patellar dislocation will provide valuable information to clinicians.

Postoperative Access and Compliance Following Medial Patellofemoral Ligament Reconstruction in Hispanic Adolescents Mirrors the Non-Hispanic Adolescent Population.

Disparity in surgical care of patellar instability patients has not been fully investigated in the adolescent Hispanic population. This demographic has been shown to have differences in their care, including a lower rate of surgical treatment for patellar instability. Socioeconomic factors have been cited as a factor that influences patient outcomes and its relationship with ethnicity in context of patellar instability has not been evaluated. Review performed of patients <19 years of age who underwent MPFL reconstruction between September 2008 and December 2015. Demographics, patient median household income data, and clinical variables were collected. Generalized linear mixed model (GLMM) with subject as random effects factor was utilized to evaluate differences between ethnicity groups due to nonindependence of data. It was then expanded to incorporate interactions between ethnicity and income. Ninety-five patellar dislocation events met criteria in 85 adolescents (mean age: 15.5y). Thirty-four (40%) adolescents identified as Hispanic. In univariate analysis no differences were found between Hispanic and non-Hispanic patients. The multivariate GLMM demonstrated a significant interaction between ethnicity and income. The Hispanic group in the >100% State median income category had the highest rate of postoperative clinic appointments attended ( P =0.019). The Hispanic group in the <100% State median income category had the lowest rate of physical therapy appointments attended ( P =0.044). No differences were observed for duration of follow-up ( P =0.57) or final Kujala score ( P =0.75). Hispanic ethnicity alone is not associated with inferior postoperative management after MPFL reconstruction in adolescents. However, when socioeconomic status is considered, Hispanic patients of lower-income backgrounds are found to have lower compliance with postoperative rehab recommendations. Level III.

Medial Patellofemoral Ligament Reconstruction Improves Patella Alta.

Patellofemoral instability (PFI) is a common problem with various anatomic risk factors identified, including patella alta as one of the most powerful predictors. Given that the medial patellofemoral ligament (MPFL) is the primary soft tissue stabilizer of the patella, a common procedure to treat recurrent patellar instability is MPFL reconstruction. The aim of this study is to examine the relationship between MPFL reconstruction and patellar height. We hypothesize that after reconstruction, patellar instability patients would have demonstrable reduction in patella height and patella alta correction. Patient records were queried for patients who underwent MPFL reconstruction for recurrent patellar instability. Patient and operative demographics were collected. We measured Insall-Salvati ratio (ISR), Caton Deschamps index (CDI), and Blackburne-Peel ratio (BPR) in all patients at various time points. The height indices were compared across the preoperative, immediately postoperative, and 6-month time points in a pairwise fashion using paired-sample t-tests. Further subgroup analysis of patients (n=27) with elevated preoperative Caton Deschamps Index (defined as >1.3) was completed. The final cohort was 103 patients. There was a significant difference between pre- and postoperative ISR (P<0.001) and at 6-month follow up (P<0.001), between preoperative CDI and the 6-month follow-up (P<0.0010), and between the postoperative and preoperative CDI (P<0.001). There was also a difference between preoperative and postoperative BPR (P<0.001), as well as between the preoperative and 6-month follow-up BPR (P=0.002). Twenty-seven patients had an initial CDI greater than 1.3. Differences were observed between pre- and postoperative mean CDI (P=0.001) and at 6-month follow-up (P=0.006), between both postoperative and 6-month ISR (both P<0.001), and preoperative mean BPR and the postoperative (P=0.004) and 6-month mean BPR (P=0.027). Patients with pre-existing patella alta and recurrent patella dislocations who undergo isolated MPFL reconstruction have decreased patella alta at their 6-month follow-up as measured by ISR, CDI, and BPR. Patients without patella alta do not demonstrate statistically significant differences after their MPFL reconstruction. III (retrospective comparative study).

Thick-shell sulcus-deepening trochleoplasty for recurrent patellar dislocation leads to clinically meaningful improvements and high patient satisfaction in adolescents with open physes

ObjectivesTo evaluate clinical and radiological outcomes of thick-shell, sulcus-deepening trochleoplasty in patients with open distal femoral physes and less than two years of growth remaining. We hypothesized that patients would have clinical and radiographic improvements in addition to high patient-reported outcomes following thick-shell, sulcus-deepening trochleoplasty. MethodsBone age was determined on preoperative magnetic resonance imaging (MRI) using the Pennock Knee Bone Age Atlas. Pre- and postoperative radiographs were used to measure the anatomic lateral distal femoral angle (aLDFA) and Blumensaat angle. International Knee Documentation Committee (IKDC), Kujala, and numerical patient satisfaction scores were assessed. Pre- and postoperative aLDFA and Blumensaat angles as well as patient-reported outcomes were analyzed via the Wilcoxon signed-rank test. ResultsSeventeen adolescents (21 knees) with DeJour Types B and D trochlear dysplasia and open distal femoral physes underwent Dejour thick-shell, sulcus-deepening trochleoplasty at a single institution. In twelve females (16 knees, 76.2%) the median chronological and bone ages at the time of operation were 14.9 and 14.3 years, respectively. In 5 males (5 knees, 27.7%), the median chronological and bone ages at the time of operation were 15.7 and 15.2 years, respectively. Mean follow-up time was 64 months postoperatively. Physes were closed in all knees at the time of final clinical and radiographic follow-up. The mean change in aLDFA and Blumensaat Angle was 0.73 (p ​= ​0.1074, 95% CI -0.09–1.57) and 0.88° (p ​= ​0.0477, 95% CI 0.10–1.88), respectively. Median IKDC scores improved from 57.3 preoperatively to 90.9 postoperatively, for a mean difference of 26.1 (p ​= ​0.00064, 95% CI 18.0–34.2). Median Kujala scores improved from 55.0 preoperatively to 95.0 postoperatively, for a mean change of 30.2 (p ​= ​0.0008, 95% CI 19.6–40.8). Overall mean numerical patient satisfaction was high (mean 9.26/10). One of 21 knees (4.8%) underwent additional surgery to address recurrent patellar instability. ConclusionThick-shell sulcus-deepening trochleoplasty for addressing recurrent lateral patellar instability in patients with open distal femoral physes and less than two years of growth remaining is safe and provides clinically meaningful improvements in addition to high patient satisfaction when combined with other patellar stabilization procedures. Level of evidenceIV, Retrospective Case Series.

Good 5-year results and a low redislocation rate using an á la carte treatment algorithm for patellofemoral instability in patients with severe trochlea dysplasia.

Trochlear dysplasia is a major risk factor for recurrent patellar instability, reduced quality of lifeand osteoarthritis of the patellofemoral joint. Patellar instability in patients with trochlear dysplasia can be treated by trochleoplasty, usually in combination with medial patellofemoral ligament reconstruction (MPFL-R). An á la carte treatment algorithm, which also addresses patella alta, lateralisation of the tibial tuberosityand valgus or torsional malalignment when present has been standard in one clinic for treatment of patellar instability patients since 2009, based on the hypothesis that it results in optimal subjective and clinical outcome, normalisation of the lateral trochlea inclination (LTI) angle and a low rate of patellar redislocation. This prospective study reports the 5-year results for consecutive patients with high-grade trochlea dysplasia operated according to the algorithm 2010-2017, evaluated preoperatively and 1, 2and 5 years postoperatively. Clinical information on previous surgery and postoperative patellar stability, range-of-motion (ROM)and subsequent surgery were registered. Subjective outcome was evaluated by four patient-reported outcome measures (PROMs): Kujala, Lysholm, International Knee Documentation Committee and Knee injury and Osteoarthritis Outcome Score. The LTI angle was measured pre- and postoperatively on magnetic resonance imaging scans. There were 131 patients (87 females) with a median age of 22 years (range: 14-38). All had a trochleoplasty and an MPFL-R. Additional procedures (tibial tuberosity medialisation/distalisation and/or femoral/tibial osteotomy) were performed in 52%. All PROM scores improved from preoperatively to 1-year follow-up with further improvement at 2 and 5 years after surgery (p < 0.05). Three patients (2%) had a traumatic patellar dislocation 9, 12and 24 months postoperativelyand 38% underwent subsequent surgery (hardware removal, arthroscopically assisted brisement force, knee arthroscopy). A normalisation of the LTI angle (≥11°) was achieved in 76%. Treatment according to the à la carte algorithm for patients with patellar instability and high-grade trochlear dysplasia resulted in significant clinical and subjective improvement in all PROM scores and a very low redislocation rate (2%) 5years after surgery. Level II.

Tibial tubercle osteotomy (TTO): A review of impactful papers in the literature

BackgroundTibial tubercle osteotomy (TTO) is a procedure that can be used as an alternative to total knee arthroplasty (TKA) or to address patellar instability in patients experiencing dislocation events. The purpose of this paper is to systematically evaluate the most cited articles pertaining to TTO through bibliometric analysis. MethodsA search using the Web of Science database with keywords pertaining to TTO was conducted in April 2024. Articles with the most citations that met all inclusion criteria were analyzed to determine information such as level of evidence (LoE), article topic, journal of publication, year published, country of origin, and institution of origin. ResultsThe average number of citations was 79 (range of 42–334). The decade with the most publications was from 2010 to 2019 (n = 26; 52%). Clinical Orthopaedics and Related Research was the journal with the largest number of published articles (n = 9, 18%). The United States (US) (n = 25; 50%) and France (n = 4; 8%) were the two countries with the most publications. Mayo Clinic (n = 3, 6 %), Ohio State University (n = 3, 6%), and Rush University (n = 3, 6%) were the institutions contributing the most articles. The LoE most reported was level 4 (n = 22; 44%). Topics were primarily related to clinical outcomes (n = 38; 76%). ConclusionThis analysis revealed that most articles were related to clinical outcomes and have been published since 2000. By analyzing the characteristics of the most cited articles, an understanding of current research and identification of areas for further exploration can be determined for TTO. Study DesignCross-sectional study. Level of EvidenceIII.

Poster 306: Establishing the Minimum Clinically Important Difference Two Years Following Medial Patellofemoral Ligament Reconstruction

Objectives: Medial patellofemoral ligament (MPFL) reconstruction is used to address cases of recurrent patellar instability. Minimal clinically important difference (MCID) is an important marker that relays the smallest clinical improvement in which patients feel a significant change after surgery. MCID has been previously established for MPFL reconstruction after 6 months and 1 year. To date, no study has established MCID for patient reported outcomes 2 years after MPFL reconstruction. The purpose of this study is to define the MCID for the Kujala, International Knee Documentation Committee (IKDC), and Knee Injury and Osteoarthritis Outcome Score for Joint Reconstruction (KOOS JR) at minimum two-year follow-ups after isolated MPFL reconstruction. Methods: All patients undergoing isolated MPFL reconstruction for recurrent patellar instability at a single institution between December 2015-June 2021 were included. Patients with concomitant osseous procedures beyond chondroplasty and any ligamentous procedure were excluded. A distribution-based approach was used to calculate the MCID. This was performed by determining the standard deviation (SD) of the delta two-year patient reported outcome scores (PROS) and then multiplying the SD by 0.5. The number of patients achieving MCID were then presented as a percentage. Results: Eighty-six of 117 patients who underwent isolated MPFL reconstruction completed preoperative and a two-year follow-up PRO survey (59 female, 27 male; age 21.1 ± 8.7 years). For Kujala, the preoperative mean was 59.3 ± 17.1, two-year follow-up mean was 87.6 ± 13.6, and MCID was 9.2 with 88% of the cohort achieving MCID. For IKDC, preoperative mean was 50.2 ± 17.2, two-year mean was 80.5 ± 18.6, and MCID was 12.4 with 80% of patients achieving MCID. KOOS JR had a preoperative man of 66.0 ± 14.6, two-year follow-up mean of 88.8 ± 11.9, and MCID of 8.5 with 72% of patients meeting this MCID (Figure 1). Conclusions: At two years following MPFL reconstruction, the MCID’s for clinically relevant subjective PROS were 9.2 (Kujala), 12.5 (IKDC), and 8.5 (KOOS JR). MCID’s for MPFL reconstruction are already established for 6-month and 1-year time points, and this was the first presentation of two-year MCID values. Establishing the 2-year MCID for MPFL reconstruction gives surgeons another tool to use in the diagnoses of patellar instability patients who may be struggling post-operatively.

Evaluation of the Results of Reconstruction of Medial Patellofemoral Ligament in the Treatment of Recurrent Patellar Instability Using Hamstring Autograft by Dual Patella Docking Technique

Abstract Background: Recurrent patellar instability can significantly affect a patient’s life quality. This study evaluated the results of medial patellofemoral ligament (MPFL) reconstruction in the recurrent patellar instability treatment using hamstring autograft by dual patellar docking technique. Materials and Methods: This prospective study was performed on 20 recurrent patellar instability patients. Magnetic resonance imaging and computed tomography scans were performed to confirm MPFL tear and assess the tibial tubercle-trochlear groove distance. Various clinical and radiographic evaluations were performed preoperatively. The surgical technique involved diagnostic arthroscopy, graft preparation, patellar preparation, graft passage, femoral tunnel preparation, and graft fixation. Results: Postoperatively, a substantial progression was observed in the International Knee Documentation Committee score, Kujala score, Cincinnati score, and Lysholm score compared to preoperative values (P &lt; 0.001). In addition, the postoperative measurements of patellar tilt angle and patellar congruence angle were significantly lower than their respective preoperative values (P &lt; 0.001). All 20 (100%) patients had negative findings in the postapprehension test, indicating improved stability. In the postcompression test, 3 (15%) patients showed positive results, whereas 17 (85%) patients had negative results. In terms of complications, 2 (10%) patients experienced patellofemoral pain, 1 (5%) patient had residual patellar translation without dislocation, 1 (5%) patient had limited flexion, and the majority of patients (16, 80%) had no complications. Conclusions: MPFL reconstruction with patellar docking yielded good results with Kujala and Lysholm, as well as adequate, satisfactory congruence angles for most patients. This procedure has exhibited a high success rate in addressing patellofemoral instability.

Correlations of Different Objective and Patient Related Outcome Measures for Patellar Instability Patients

Correlations of Different Objective and Patient Related Outcome Measures for Patellar Instability Patients

Association between single leg hop tests and patient reported outcome measures and patellar instability in patients with recurrent patellar dislocations

ObjectivesTo assess the associations between the single leg hop tests at two premises; baseline and the change after 12 months, and change in patient reported outcome measures and persistent instability...

Wavelet Analysis of Rearfoot Loading of Patients After Medial Patellofemoral Ligament (MPFL) Reconstruction

Abstract Introduction. Patellar instability in younger patients is a common injury (3.3% of all knee injury episodes) and the most frequent dislocation of the knee observed. The sensitivity and reliability of clinical diagnostic tests after medial patellofemoral ligament (MPFL) reconstruction remain unclear and biased. The primary aim of the present study was thus to detect, using wavelet analysis, differences in the rearfoot loading of the operated limb of patients after MPFL reconstruction. The authors hypothesised that applying this specific examination technique would allow for more accurate and less biased clinical results evaluation. Material and Methods. The study involved a group of 15 female subjects (age: 22.8 ± 6.3 years; weight: 58.5 ± 5.1 kg) after MPFL reconstruction and a control group of 29 healthy females (23.2 ± 2.8 years; 61.1 ± 7.7 kg). The subjects performed a 30-second classic Romberg test on a treadmill (Noraxon FDN-T) equipped with a matrix of baroresistive sensors to measure ground reaction forces. Time-frequency analysis of the signal originating from the treadmill was done using an analytic Morse wavelet. Results. The results indicate differences in visual control and vestibular stability in patients before and 3 months after a surgery. They are characterised by a deficit of energy attributed to visual control in favour of an excess of energy associated with vestibular control. Patellar instability patients show greater energy expenditure to maintain body balance for at least 6 months after MPFL reconstruction. Conclusions. Patellar instability patients have increased vestibular control while maintaining balance. Our results suggest an extended rehabilitation period for patients after MPFL reconstruction beyond 6 months.

Trochleoplasty: Groove-Deepening, Recession Wedge, and Entrance Grooveplasty

Patellar instability in patients with a dysplastic trochlea can be challenging to treat without addressing the trochlea directly. Trochleoplasty allows the surgeon to target a root osseous cause of instability and is an effective treatment option in well-selected patients. This chapter explores the variations in trochleoplasty techniques and offers an overview of recently published data associated with this surgery.

Tibial Tuberosity Rotation in Patients With Patellar Instability Versus Age- and Sex-Matched Controls.

Several methods have been described to measure external rotation of the tibial tuberosity; all use femoral landmarks. To develop reproducible tibial-based methods to measure external rotation of the tibial tuberosity in patients with patellar instability. Cross-sectional study; Level of evidence, 3. Included were magnetic resonance images of 61 patients with patellar instability and 61 age- and sex-matched healthy controls. Three novel methods using tibial landmarks to measure the rotation of the tibial tuberosity (plateau axis-tuberosity axis [PA-TA] angle, tibial geometric center-tuberosity axis [GC-TA] angle, and plateau axis-midtuberosity point [PA-MT] angle) as well as a femoral-based rotational measurement (surgical transepicondylar axis-tuberosity axis [sTEA-TA] angle) and the tibial tuberosity-trochlear groove (TT-TG) distance were measured and compared in instability patients and controls using unpaired t tests, and the cutoff values for predicting instability were calculated using receiver operating characteristic curves. The correlations between the angle measurements and the TT-TG distance were analyzed. Instability patients had significantly higher external rotation of the tibial tuberosity compared with controls with regard to the PA-TA angle (18.2° ± 9.6° versus 13.1° ± 6.8°; P = .001), GC-TA angle (8.4° ± 4.5° versus 11.5° ± 3.9°; P = .0001) and sTEA-TA angle (122° ± 8.5° versus 113.6° ± 6.3°; P = .0001). The mean TT-TG distance was also significantly higher in the instability group (18.2 ± 5.4 versus 11.5 ± 2.7 mm; P = .001). The cutoff values were 17.5° (area under the receiver operating characteristic curve [AUC] = 0.66) for PA-TA angle, 8.5° (AUC = 0.705) for GC-TA angle, 118.8° (AUC = 0.79) for sTEA-TA angle, and 15.2 mm for TT-TG distance (AUC = 0.863). PA-TA angle was significantly correlated with all other measurements (r = 0.35-0.71; P ≤ .006 for all), whereas sTEA-TA angle had the strongest correlation with TT-TG distance (r = 0.78; P = .001). The tibial tuberosity was externally rotated in patellar instability patients compared with age- and sex-matched controls, and this intrinsic malalignment of the proximal tibia was demonstrated in the tibial-based measurements.

Medium to long-term outcomes of medial patellofemoral ligament reconstruction using the superficial quadriceps versus a hamstring autograft in patellar instability patients

Medial patellofemoral ligament (MPFL) reconstruction is a standard procedure in patellar dislocation patients. Superficial quadriceps autografts (QA) and hamstring autografts (HA) are popular graft choices in MPFL reconstruction with the lack of directly compared clinical studies between both methods. A total of 43 patellar instability patients, who underwent QA and HA for patellar stabilization at a specified center between 2012 and 2021, were retrospectively reviewed. 21 QA and 22 HA patients were 52.4% of males and 47.6% females with a median age of 25 years (range 12–58) in the QA group, while 63.6% were females with a median age of 21 years (range 14–58) in the HA group. The mean follow-up period was 46.9 months (range 24–77) in QA and 61 months (range 24–100) in the HA group. At the final follow-up, no complications were observed with either technique. No patients presented with recurrent dislocations after surgery. There was no statistically significant difference in postoperative mean Kujala scores (QA = 94.9+/− 4.1 and HA = 94.2+/− 8.0, p = 0.73) or the mean Lysholm scores (QA = 94.1+/− 5.0 and HA = 93.2+/− 7.0, p = 0.61).

Home ownership, full-time employment, and other markers of higher socioeconomic status are predictive of shorter time to initial evaluation, shorter time to surgery, and superior postoperative outcomes among lateral patellar instability patients undergoing medial patellofemoral ligament reconstruction

BackgroundThe purpose of this study was to identify socioeconomic predictors of time to initial evaluation, time to surgery, and postoperative outcomes among lateral patellar instability patients undergoing medial patellofemoral ligament reconstruction (MPFLR).MethodsWe conducted a retrospective review of patients at our institution who underwent primary MPFLR with allograft from 2011 to 2019 and had minimum 12-month follow-up. Patients were administered an email survey in January 2022 to assess symptom history, socioeconomic status, and postoperative outcomes including VAS satisfaction and Kujala score. Predictors of time to initial evaluation, time to surgery, and postoperative outcomes were identified using multivariable linear and logistic regression with stepwise selection.ResultsSeventy patients were included in the cohort (mean age 24.8 years, 72.9% female, mean follow-up time 45.7 months). Mean time to evaluation was 6.4 months (range 0–221) and mean time to surgery was 73.6 months (range 0–444). Having a general health check-up in the year prior to surgery was predictive of shorter time to initial evaluation (β = − 100.5 [− 174.5, − 26.5], p = 0.008). Home ownership was predictive of shorter time to surgery (β = − 56.5 [− 104.7, 8.3], p = 0.02). Full-time employment was predictive of higher VAS satisfaction (β = 14.1 [4.3, 23.9], p = 0.006) and higher Kujala score (β = 8.7 [0.9, 16.5], p = 0.03).ConclusionMarkers of higher socioeconomic status including having a general check-up in the year prior to surgery, home ownership, and full-time employment were predictive of shorter time to initial evaluation, shorter time to surgery, and superior postoperative outcomes.Level of evidence: IV, retrospective case series.

The Value of Minimal Clinically Important Difference, Substantial Clinical Benefit, and Patient-Acceptable Symptomatic State for Commonly Used Patient-Reported Outcomes in Recurrent Patellar Instability Patients After Medial Patellofemoral Ligament Reconstruction and Tibial Tubercle Transfer

To identify the minimal clinically important difference (MCID), substantial clinical benefit (SCB) and patient acceptable symptomatic state (PASS) for commonly used patient-reported outcomes (PROs) in recurrent patellar instability patients after medial patellofemoral ligament reconstruction (MPFLR) and tibial tubercle transfer (TTT), and to determine the impact of potential prognostic factors on the likelihood of achieving these values. From April 2015 to February 2021, patients who underwent MPFLR and TTT were retrospectively reviewed. PROs included Kujala, Knee Injury and Osteoarthritis Outcome (KOOS), Lysholm, International Knee Documentation Committee (IKDC) and Tegner score. Relevant anchor questions were provided. A distribution- or anchor-based method was adopted to determine the MCID, SCB and PASS. Minimal detectable change (MDC) was included to confirm the validity. Univariate regression analyses were conducted to determine the potential prognostic factors. 142 patients were included. The MCID were 9.1(Kujala), 11.1 (Lysholm), 0.9(Tegner), 9.9(IKDC), 9.0(KOOS-Pain), 10.8(KOOS-Symptoms), 10.0(KOOS-Activities of Daily Living (ADL)), 17.8(KOOS-Sports and Recreation (Sports/Rec)), and 12.7 (KOOS-Quality of Life (QoL)). The SCB were 14.5(Kujala), 12.5(Lysholm), 1.5(Tegner), 14.5(IKDC), 13.9(KOOS-Pain), 14.3(KOOS-Symptoms), 18.4(KOOS-ADL), 47.5(KOOS-Sports/Rec), 15.0(KOOS-QoL). The PASSs were 85.5(Kujala), 75.5(Lysholm), 3.5(Tegner), 73.2(IKDC), 87.5(KOOS-Pain), 73.2(KOOS-Symptoms), 92.0(KOOS-ADL), 77.5(KOOS-Sports/Rec), and 53.1(KOOS-QoL). All SCBs were valid except KOOS-QoL. All MCIDs were valid at the 95% confidence interval (CI) except KOOS scores, the majority of which were valid at the 90% CI. A younger age was an independent prognostic factor of reaching PASS for Lysholm, IKDC, Tegner and KOOS-ADL score. A higher baseline score was a negative prognostic factor for achieving MCID or SCB but had a slightly positive influence on the achievement of PASS. This study established the MCID, SCB, and PASS for commonly used PROs and confirmed their validity in recurrent patellar instability patients after MPFLR and TTT. Younger age and lower baseline scores were prognostic factors of achieving MCID and SCB, while patients with higher baseline scores were more likely to report satisfaction.

Differences in the Severity and Location of Patellofemoral Cartilage Damage Between Instability Patients With and Without Patella Alta.

Patella alta is a risk factor for recurrent patellar instability. Differences in chondral injury in patients with patellar instability between patella alta and patella norma have not been evaluated. To analyze whether preoperative cartilage damage differs in severity and location between patellar instability patients with and without patella alta. Cohort study; Level of evidence, 3. Patients with patellar instability who underwent patellar realignment surgery at a single institution with preoperative magnetic resonance imaging (MRI) scans were included. After measurement of Caton-Deschamps index (CDI) on MRI, patients were divided into patella alta (CDI ≥1.3) and patella norma groups. The area measurement and depth and underlying structures (AMADEUS) score was used to quantify cartilage defect severity on MRI. A total of 121 patients were divided into patella alta (n = 50) and patella norma (n = 71) groups. The groups did not differ significantly in sex ratio, age at MRI, body mass index, mean reported number of previous dislocations, or mean interval between first reported dislocation and date of MRI. A total of 34 (68%) of the patella alta group and 44 (62%) of the patella norma group had chondral defects (P = .625) with no significant between-group differences in defect size (P = .419). In both groups, chondral injuries most affected the medial patellar facet (55% in patella alta vs 52% in patella norma), followed by the lateral facet (25% vs 18%), and lateral femoral condyle (10% vs 14%). A smaller proportion of patients had full-thickness defects in the patella alta compared with the patella norma group (60% vs 82%; P = .030). The overall AMADEUS score was higher for the patella alta versus the patella norma group (68.9 vs 62.1; P = .023), indicating superior articular cartilage status. Patients with patella alta had less severe cartilage injury after patellar instability, including a lower proportion with full-thickness defects and better overall cartilage grade. The location of injury when present was similar between alta and norma, with most defects affecting the medial facet, lateral facet, and lateral femoral condyle in descending frequency.

Poster 295: Surgical Management and Outcomes of Patellar Instability in Hispanic Adolescents Mirrors the General Adolescent Population

Objectives: Literature has shown that there are differences in care across demographics for sports- related injuries. Delay to physician evaluation, delay to surgery, and decreased surgical management has been documented in common pathology such as ACL tears and Shoulder Instability. Recent research has demonstrated that for Patellar Instability in adolescents, African-American patients had lower odds of having surgical management in addition to their care costing more overall, even when controlled for insurance status. The Hispanic population is a growing minority group who face challenges not just in economic status, but language barriers that may also impart inequitable care for one of the most common diagnoses seen in a Sports clinic. The purpose of this study is to assess for any major differences in care provided to adolescent patients who identify as Hispanic compared to the remainder of the adolescent population. Methods: Patellar Instability patients who underwent MPFL Reconstruction at a single center between September 2008 through December 2015 were collected. Inclusion criteria were age &lt; 19 at time of surgery, preoperative and postoperative data available during chart review, case was performed as the index primary reconstructive procedure, and minimum of 3 month follow-up data available. Charts were reviewed to gather demographic and clinical information including age, sex, race, ethnicity, number of instability episodes, MRI at time of initial evaluation, time from injury to surgery, engagement in postoperative physical therapy, number of postoperative visits attended, Kujala score, and complications. Independent variable t-test was used for analysis of number of clinic visits, therapy sessions, and the Kujala score. The remainder of analysis was completed using χ2 testing. Significance was set at p = 0.05. Results: 95 patients (40 male (42%), 55 female (58%)) met the inclusion criteria. Mean patient age was 15.5. 37 patients identified as Hispanic (38.9%) and 58 (61.1%) of patients identified as non-Hispanic. 58.5% of all patients had an MRI available at their first clinic visit, 69.2% of patients had 2 or more dislocation events prior to surgery, and 37% of patients were formally cleared for return to activity. Hispanic patients more frequently had an MRI prior to surgery compared to non-Hispanic patients (73% vs 50%, p = .039). Otherwise, there was no statistically significant difference in observations between Hispanics patients and non-Hispanic patients, including number of dislocations prior to surgery (p = 0.13), number of clinic visits preoperatively or postoperatively (p = 0.51 and 0.09, respectively), number of therapy sessions attended postoperatively (p = 0.46), or the patient reported outcome as measured by the Kujala score (mean = 91.56 vs 95.25, p = 0.13). Complications in the cohort included 1 infection and 1 case of arthrofibrosis. 2 patients in the Hispanic cohort required revision for recurrent instability compared with 5 patients in the non-Hispanic cohort (p = 0.56). Conclusions: Adolescents with patellar instability who identify as Hispanic had similar outcomes scores and complication rates after operative treatment in the form of MPFL Reconstruction. Hispanic patients more frequently had an MRI at their first clinic visit prior to surgery, but the remainder of the perioperative work-up and care was similar to the non-Hispanic cohort. Though significant deviations in care were not found in this study, reviews to elucidate any variations in care should continue in efforts to ensure equitable treatment of at-risk populations.