Changes In Patellar Height Research Articles

Changes in patellar baja progress until 3 months after medial open-wedge high tibial osteotomy.

The purpose of this study was to evaluate sequential patellar height changes as well as the factors leading to these changes after medial open-wedge high tibial osteotomy (MOWHTO). The study cohort constituted 37 knees from 36 patients who underwent MOWHTO for varus knee. The Caton-Deschamps index (CDI) for patellar height was measured preoperatively and at 2 weeks and 3, 6, and 12 months postoperatively. The factors related to sequential changes in patellar height were evaluated. Significant differences were observed between preoperative CDI and postoperative CDI at all time points (p < .05). Two-week postoperative CDI and postoperative CDI at 3,6,12-months was also significantly different (p < .05). The only significant factor for the change in patellar height between preoperative CDI and postoperative CDI at 2-weeks and 12-months was the change in the Δ medial proximal tibial angle (ΔMPTA) (postoperative MPTA-preoperative MPTA). We could not identify the factor that affected the change in patellar height change from 2-weeks postoperatively. The change in patellar height continued sequentially until at least 3 months postoperatively. ΔMPTA was associated with the change in patellar height at 2weeks postoperatively compared with preoperatively; however, no factors associated with the change in patellar height from 2weeks postoperatively to 3, 6, and 12-months postoperatively were identified.

Poster 202: Patellar Stabilization Procedures Not Performed to Address Alta Decrease Patellar Height

Poster 202: Patellar Stabilization Procedures Not Performed to Address Alta Decrease Patellar Height

Patellofemoral arthroplasty: obesity linked to high risk of revision and progression of medial tibiofemoral osteoarthritis.

The purpose of this study was to determine the effect of obesity on patient outcome, procedure failure rate and osteoarthritis (OA) progression in the tibiofemoral compartments in a series of isolated patellofemoral arthroplasty (PFA) performed with a third-generation implant. The study population was patients who had undergone third-generation PFA at a specialized orthopedic center between 2007 and 2017. Patients were categorized by body-mass index (BMI) as obese (O, BMI > 30kg/m2) or nonobese (NO, BMI < 30kg/m2). Preoperative and postoperative clinical and functional assessment included knee range of motion, Knee Society Score (KSS), University of California Los Angeles (UCLA) Activity Score, Tegner Activity Level Scale, and visual analogue scale (VAS) for pain. Preoperative and postoperative radiographs were evaluated for progression of tibiofemoral compartment OA, changes in patellar height and in knee coronal alignment. Multiple logistic regression models were used to assess the effect of BMI on outcomes together with other covariates. A total of 120 PFAs with a mean follow-up of 6.9 ± 2.5years were included: 25 in the O group and 95 in the NO group. Significant improvement was noted in in knee range of motion (P < 0.001), clinical and functional KSS (P < 0.001), UCLA Activity Score (P < 0.001), Tegner score (P < 0.001) and VAS pain (P < 0.001) without inter-groups differences. Worsening of the medial Kellgren-Lawrence (KL) grade (but not the lateral KL grade) was more frequent in the O than the NO group during the follow-up period (P = 0.014). Failure occurred in 4.2% of NO and in 20% of O group patients; the difference was solely due to failure because of OA progression in the tibiofemoral compartment (16% in the O group). There were no between group differences in the failure rate for any cause other than OA progression (4.2% in the NO group, 4.0% in the O group). An equal improvement in function after PFA was noted in both obese and nonobese patients; however, the high failure rate due to OA progression in the medial tibiofemoral compartment warrants caution when considering PFA in obese patients.

Combined Anterior Opening-Wedge High Tibial Osteotomy and Tibial Tubercle Osteotomy with Posterior Cruciate Ligament Reconstruction

Despite multiple advances in techniques for posterior cruciate ligament reconstruction (PCL-R), residual posterior laxity continues to be a commonly reported complication. Multiple studies demonstrated a decreased or flat posterior tibial slope, increases posterior laxity, and forces placed across the native and reconstructed PCL. Anterior opening wedge high tibial osteotomies (aOW-HTO) can be used to increase posterior tibial slope, thereby reducing tibial sag and posterior laxity. Depending on the technique used, anterior opening wedge osteotomies can lead to changes in patellar height, affecting patient pain and satisfaction. The purpose of this article is to describe a technique for an aOW-HTO with a tibial tubercle osteotomy and concomitant PCL-R to increase the posterior tibial slope while minimizing changes to patellar height.

MODELING OF PATELLA HEIGHT WITH DISTAL FEMUR AND PROXIMAL TIBIA REFERENCE POINTS WITH ARTIFICIAL NEURAL NETWORK

The patellofemoral joint is one of the parts of the knee extension mechanism that plays a role in the stability of the knee by enlarging the force arm of the quadriceps muscle and changing the direction of the muscle strength. For the entire knee joint to perform its task painlessly and functionally, the positions and strength of the muscles, the strength of the ligaments, and their reaction to movement must be compatible. The Insall–Salvati (Ins-Sal) index is useful for showing changes in patellar height produced by repositioning the tibial plateau, in other words, showing changes in patellar tendon length. Patella height is an important value to be taken into account in knee prosthesis surgery, tibial osteotomy, and anterior cruciate ligament reconstruction. The morphometric relationship between the reference measurements of the distal femur and proximal tibia and the position of the patella will be useful in determining the natural anatomy. In this study, we aimed to determine the relationship between patella height and distal femur and proximal tibia reference areas by using the artificial neural network method as an alternative approach method. In order to assess the performance of the estimation of the Ins-Sal index, the four ANN model with six input combinations which included age, gender and the reference measurements for the right and left sides have been constructed and tested. The MSE and [Formula: see text] values are calculated for every four models for the training and test phase. The results show that the proposed approach for modeling of relation between reference measurements and the Ins-Sal index is a powerful approach.

Changes in patellar height after anatomical ACL reconstruction with BTB autograft with a focus on patellar tendon removal volume

BackgroundAlthough anatomical anterior cruciate ligament reconstruction (ACLR) can provide satisfactory outcomes, little is known about how this procedure impacts patellar height. Since harvesting bone-patellar tendon-bone (BTB) autografts is a potential risk factor for decreased patellar height, we examined changes in patellar height after anatomical ACLR with BTB autograft with a focus on the size of the harvested graft. MethodsSubjects were 84 patients (49 males, 35 females; mean age, 23 years) who underwent primary anatomical ACLR with central third BTB autograft. Preoperative to postoperative Caton-Deschamps index (CDI) ratio was calculated using lateral knee radiographs before and 6 months after surgery. The length and cross-sectional area (CSA) of the graft were measured intraoperatively, and the CSA of the contralateral patellar tendon was measured by ultrasound 6 months postoperatively. The difference in graft CSA relative to the contralateral tendon CSA, expressed as a percentage (gCSA:ctCSA percentage), was also calculated. ResultsPatellar height decreased slightly after surgery (preoperative CDI: 0.856 ± 0.113; postoperative CDI: 0.841 ± 0.113), with a mean difference between preoperative and postoperative CDIs of −0.015 (range: −0.293 to 0.101). Although the CDI of male subjects significantly decreased after surgery (preoperative: 0.852 ± 0.117; postoperative: 0.827 ± 0.115), no significant changes were noted in female subjects (preoperative: 0.862 ± 0.108; postoperative: 0.861 ± 0.108). Graft length and CSA did not significantly impact the CDI ratio (r = −0.138 and r = −0.038, respectively). Moreover, no significant relationship was observed between the gCSA:ctCSA percentage and CDI ratio (r = 0.118). ConclusionsAlthough patellar height slightly, but significantly, decreased at 6 months after anatomical ACLR with BTB autograft, it was not affected by the length and CSA of harvested grafts. The decrease in postoperative patellar height was observed only in male subjects, suggesting the potential importance of sex differences in soft tissue healing during the postoperative period.

Significant reduction of patellar height affected lower clinical outcomes and knee flexion over five-year follow-up after total knee arthroplasty.

AimsThis study aimed to investigate the relationship between changes in patellar height and clinical outcomes at a mean follow-up of 7.7 years (5 to 10) after fixed-bearing posterior-stabilized total knee arthroplasty (PS-TKA).MethodsWe retrospectively evaluated knee radiographs of 165 knees, which underwent fixed-bearing PS-TKA with patella resurfacing. The incidence of patella baja and changes in patellar height over a minimum of five years of follow-up were determined using Insall-Salvati ratio (ISR) measurement. We examined whether patella baja (ISR < 0.8) at final follow-up affected clinical outcomes, knee joint range of motion (ROM), and Knee Society Score (KSS). We also assessed inter- and intrarater reliability of ISR measurements and focused on the relationship between patellar height reduction beyond measurement error and clinical outcomes.ResultsThe ISR gradually decreased over five years after TKA, and finally 33 patients (20.0%) had patella baja. Patella baja at the final follow-up was not related to passive knee ROM or KSS. Interestingly, when we divided into two groups - patella baja and patella normal-alta (ISR ≥ 0.8) - the patella baja group already had a lower patellar height before surgery, compared with the patella normal-alta group. The ISR measurement error in this study was 0.17. Both passive knee flexion and KSS were significantly decreased in the group with a decrease in ISR of ≥ 0.17 at final follow-up.ConclusionPatellar height gradually decreased over five years of follow-up after TKA. The reduction in patellar height beyond measurement error following TKA was associated with lower clinical outcomes.Cite this article: Bone Jt Open 2021;2(12):1075–1081.

L’ostéotomie tibiale antérieure de déflection avec préservation de la TTA ne modifie pas la hauteur rotulienne

Anterior-closing wedge high tibial osteotomy (ACW-HTO) in ACL reconstruction (ACLR) can prevent graft rupture in patients with posterior tibial slope (PTS) > 12°. Management of patellar height is of concern when performing HTO. The objective was to evaluate the effect of tibial tubercle-sparing ACW-HTO on patellar height in revision ACLR. A retrospective analysis of prospectively collected data from 2 centers was performed. All patients who underwent tibial tubercle-sparing ACW-HTO in revision ACLR were identified and included. Data regarding age, gender and body mass index were collected. Patellar height was measured on full weightbearing pre- and postoperative x-rays. The tibial-referenced indexes of Insall–Salvati (ISI), Caton–Deschamps (CDI) and Blackburne–Peel (BPI) were assessed on lateral x-rays. The Femoral Patellar Height Index (FPHI), femur-referenced, was calculated on frontal x-rays. Pre- and postoperative PTS were assessed using the proximal anatomic axis of the tibia and the tangent line to the medial tibial plateau. All radiological measurements were performed by two trained sports medicine physicians, twice at three-month intervals. Mean values were retained for statistical analysis. Inter- and intra-observer reliability were assessed for each parameter. Forty-seven tibial tubercule-sparing ACW-HTO were retained for analysis. Most patients were male (n = 32, 68.1%) with a mean age of 28.9 ± 9.2 years old (range 17–58). Good to excellent intra- and inter-observer reliability were reported for all parameters. The mean decrease in PTS was 8.60° ± 2.95 (range 3–13.6). No significant difference in patellar height was found between pre- and postoperative x-rays regardless of the index (P > .05). Linear regression investigated the influence of change in slope (delta PTS) on change in patellar height (delta and ratio). No influence of delta PTS was found on all parameters except on the CDI ratio (ratio = preoperative/postoperative, P = .0088). Multivariate analysis showed a significant influence of delta PTS on the CDI ratio (P = .0335), but none on the ISI (P = .7037), BPI (P = .6324), and FPHI (P = 5709) ratios. A change in PTS appeared to influence the Caton–Deschamps Index, but this tibial plateau-referenced method may be biased after HTO. No change in patellar height was observed with others index after tibial tubercle-sparing ACW-HTO.

EP.FRI.194 Patellar height after Anterior Cruciate Ligament rupture reconstruction using the autologous bone-patellar tendon-bone graft technique in the Maltese population

Abstract Aim The primary aim of this study is to determine whether there is a change in patellar height after closure of the patellar tendon defect after a bone-patellar tendon-bone graft harvesting. The secondary aim is to evaluate clinical and functional outcomes. Method A retrospective observational study was conducted. Patients who were diagnosed with ACL injury and underwent reconstruction of ACL using the bone- patellar tendon- bone graft technique from 2015 to 2020 were included (56 patients). All patients underwent the same procedural steps. All patients had pre- and post-operative knee radiographs (antero-posterior and lateral views). The Caton- Deschamps Index was used to measure patellar height pre- and post-operatively. The International Knee Documentation Committee-Subjective Knee Evaluation Form was used to assess functional outcome. Clinical outcome was assessed by reviewing patient records. Results There was a change from the pre-op index 0.995 +/− 0.144 (mean +/- SD) to the post-op index 0.948 +/− 0.150. With a statistically significant decrease in index of 0.048 +/− 0.131 (p value 0.009) was found. The null hypothesis (that there is no change) is rejected and therefore the alternative hypothesis (a decrease in patellar height) is accepted. The mean IKDC-SKF score was 76.851 +/− 15.015 (SD) ranging from 40.2 to 100. Conclusion Performing ACL reconstruction using the B-pT-B technique, although predisposing to a decreased patellar height, it does not increase the incidence of patella baja. An overall good functional outcome was achieved, mean IKDC-SKF 76.85. However, no clear association between change in patellar height and PF symptoms could be demonstrated.

328 Patellar Height After Anterior Cruciate Ligament Rupture Reconstruction Using the Autologous Bone-Patellar Tendon-Bone Graft Technique in The Maltese Population

Abstract Aim The primary aim of this study is to determine whether there is a change in patellar height after closure of the patellar tendon defect after a bone-patellar tendon-bone graft harvesting. The secondary aim is to evaluate clinical and functional outcomes. Method A retrospective observational study was conducted. Patients who were diagnosed with ACL injury and underwent reconstruction of ACL using the B-p-T-B graft technique from 2015 to 2020 were included (56 patients). All patients underwent the same procedural steps in the same centre. All patients had pre- and post-operative knee radiographs (antero-posterior and lateral views). The Caton- Deschamps Index was used to measure patellar height pre- and post-operatively. The International Knee Documentation Committee-Subjective Knee Evaluation Form was used to assess functional outcome. Clinical outcome was assessed by reviewing patient records. Results There was a change from the pre-op index 0.995 +/- 0.144 (mean +/- SD) to the post-op index 0.948 +/- 0.150. With a statistically significant decrease in index of 0.048 +/- 0.131 (p value 0.009) was found. The null hypothesis (that there is no change) is rejected and therefore the alternative hypothesis (a decrease in patellar height) is accepted. The mean IKDC-SKF score was 76.851 +/- 15.015 (SD) ranging from 40.2 to 100 Conclusions Performing ACL reconstruction using the B-pT-B technique, although predisposing to a decreased patellar height, it does not increase the incidence of patella baja. An overall good functional outcome was achieved, mean IKDC-SKF 76.85. However, no clear association between change in patellar height and PF symptoms could be demonstrated.

Effect of the amount of correction on posterior tibial slope and patellar height in open-wedge high tibial osteotomy.

Objectives: To evaluate the effect of amount of correction on postoperative changes in PTS (posterior tibial slope), PH (patellar height), and clinical outcomes following biplanar OWHTO (open-wedge high tibial osteotomy). Method: This study included 79 knees (32 left and 47 right) of 79 patients (mean age 60.28 ± 4.2years, 24 males, 55 females) with varus malalignment and symptomatic isolated medial joint osteoarthritis who underwent OWHTO. According to the amount of correction angles, all patients were divided into three groups: LCA (large correction angle) group (>14°), MCA (medium correction angle) group (10°-14°), and SCA (small correction angle) group (<10°). All patients were clinically assessed according to the Lysholm score, HSS (hospital for special surgery knee score), and KSS (knee society score) prior to and after surgery. For radiographic analysis, we measured the PTS, PH [ISI (Insall-Salvati index), and BPI (Blackburne-Peel index)]. The pre-post difference of PTS, ISI, and BPI was calculated by subtracting the post-OWHTO value to the pre-OWHTO value in three groups, respectively. The preoperative, postoperative, and difference of PTS, ISI, and BPI values were analyzed according to the correction angle. The mean follow-up period was 28.5months (SD, 4.9; range 18-52months). Results: Radiologically, PTS increased and PH decreased after surgery on the whole (p < .05). The relationship between amount of correction and slope increase is significant (p < .001). Furthermore, the pairwise difference between the LCA group and SCA group and MCA group is significant respectively (p < .05). In terms of PH, the LCA group yielded ISI and BPI that were significantly different from baseline for the SCA group and MCA group. In addition, the pairwise difference between the SCA group and LCA group in ISI and BPI is significant (p = .031). Clinically, significant improvements were observed in postoperative clinical scores of the Lysholm score, HSS, and KSS (p < .05). Seventy-four patients (93.67%) reported satisfaction with surgery. However, no correlation was found between changes in PTS and PH with postoperative knee score. No severe adverse complications were observed. Conclusions: The amount of correction angle is a significant factor affecting the PTS and PH in OWHTO. With increased correction angle, the likelihood of increasing the PTS and decreasing the PH increases. Special attention should be paid to keep PTS and PH unchanged in cases where large corrections are required. Otherwise, closing wedge osteotomy or other intraoperative effective measures are supposed to be adopted.

Changes in the patellar height following open wedge high tibial osteotomy

Genu varum of the knee is a predisposing factor for osteoarthritis of the medial femoro-tibial compartment. High tibial osteotomy is the surgery of choice for such patients. Patello-femoral abnormalities have a negative effect on the prognosis of high tibial osteotomy. The aim of this study is to assess the changes in patellar height after medial open wedge high tibial osteotomy.Our study was performed in kafr el sheikh university hospital, orthopedic department during the period 2018-2019 on 30 patients.All patients were subjected to thorough clinical and radiological examination and follow up of all patients with Modified Hospital for Special Surgery knee scoring scale (modified HSS), was utilized and compared with its pre-operative valuesThere was significant decrease of patellar height from preoperatively postoperatively; this difference was statistically highly significant.The conclusion was that the High tibial osteotomy using the medial opening wedge technique causes reduction in patellar height due to relative joint line elevation and obliquity and it may be almost inevitable after this type of osteotomy.

Patellar height is not modified after isolated open-wedge high tibial osteotomy without change in posterior tibial slope

IntroductionOpen-wedge high tibial osteotomy (OWHTO) corrects coronal deformity and can impact sagittal parameters such as posterior tibial slope and patellar height. The aim of the present study was to analyze change in patellar height after medial OWHTO with respect to tibial and femoral-referenced indices. Material and methodThis single-center retrospective study included 129 patients undergoing isolated posteromedial OWHTO, without change in tibial slope, using patient-specific cutting-guides. Patellar height was assessed on Caton-Deschamps (CD), Insall-Salvati (IS) and Schröter indices. Posterior tibial slope and coronal femoral and tibial angles were also measured. X-rays were taken preoperatively and at 12 months, and analyzed by 2 independent observers. ResultsOWHTO modified the global lower-limb alignment (Δ=6.3±0.95̊, p<0.0001) and the proximal tibial deformity (Δ=7±0.88̊, p<0.0001). Posterior tibial slope and tibial (CD and IS) and femoral (Schröter) patellar height indices were unchanged. Intra- and inter-observer reproducibility was excellent (ICC 0.79–0.91). There were no correlations between HKA or MPTA angles and change in patellar height. ConclusionThe present clinical series showed that patellar height was unchanged by isolated posteromedial OWHTO without change in tibial slope, using patient-specific cutting-guides, with whichever femoral or tibial reference index. The Schröter patellar femoral height index was highly reliable and is independent of proximal tibial changes in assessing patellar height, and can thus be recommended in the follow-up of OWHTO. Level of evidenceIII; retrospective cohort study.

Femoral Tunnel Fixation for Medial Patellofemoral Ligament Reconstruction in the Growing Patient

Medial patellofemoral ligament (MPFL) reconstruction has been shown to be a successful treatment for patients with recurrent patellar instability. The purpose of this study is to compare radiographic parameters prior to and following an MPFL reconstruction with femoral tunnel fixation in the skeletally immature patient to investigate potential effects on the physic and future growth. Skeletally immature patients undergoing isolated MPFL reconstruction were retrospectively reviewed. Fixation of proximal MPFL was performed as a femoral socket using Schottle’s point with the entry approximately 5 mm distal to the physis. Patients with open growth plates and 1-year post-operative standing alignments were included. Radiographic measures of patellar tilt, patellar height, patellar subluxation, and trochlear dysplasia were compared pre-operatively and post-operatively on the operative limb. Pre- and post-operative coronal alignment and limb length measurements were compared between the operative and non-operative limbs. Nineteen skeletally immature patients with an average age of 11.6 years (range 5-15 years old) underwent isolated MPFL reconstruction. The average follow-up time was 24 months. No significant differences were found between the change in femur (0.49 mm, p=0.526) or total limb length (1.08 mm, p=0.241) when comparing the operative to the non-operative limb, with an average of 47 mm of growth in the operative limb seen during the time period. There was no significant difference in the change in LDFA between operative and non-operative limb as well as symmetric changes noted in the mechanical axis. The change in patellar tilt on the operative limb was found to be significant (12.78°, p=0.030), and the change in patellar height by Caton-Deschamps approached significance (0.08mm, p= 0.077). No significant difference was found with trochlear dysplasia measures. The present study suggests MPFL reconstruction with femoral tunnel fixation is safe and does not result in growth disturbance in skeletally immature patients.

Changes in patellar height and posterior tibial slope angle following uniplanar medial opening wedge high tibial osteotomy using a novel wedge-shaped spacer implanation concurrent with proximal partial fibulectomy.

The purpose of this study was to evaluate changes of patellar height and posterior tibial slope angle following uniplanar medial opening wedge high tibial osteotomy using a novel wedge-shaped spacer implanation concurrent with proximal partial fibulectomy. All patients who underwent uniplanar medial opening wedge high tibial osteotomy using a novel wedge-shaped spacer implanation concurrent with proximal partial fibulectomy between January 2017 and February 2019 were included and assessed retrospectively. Radiological assessment was made in terms of the changes in patellar height and posterior tibial slope angle between pre-operative and post-operative radiographs. Thirty-five patients (9 males and 26 females) with a mean age of 57.3 years (range 50.8-64.2 years) were enrolled in this study protocol and demonstrated decreased posterior tibial slope angle post-operatively (9.7° ± 2.5° pre-operatively and 7.3° ± 1.8° post-operatively, P < 0.001). Patellar height was unchanged significantly post-operatively (Caton-Deschamps: 0.83 ± 0.12 pre-operatively and 0.82 ± 0.09 post-operatively, P > 0.05). Uniplanar medial opening wedge high tibial osteotomy using a novel wedge-shaped spacer implanation concurrent with proximal partial fibulectomy can decrease posterior tibial slope and maintain the patellar height.

Central Transpatellar Tendon Portal Is Safe When Used for Anterior Cruciate Ligament Reconstruction.

Central transpatellar tendon portal (CTP) was suggested first for complex meniscal lesion and subsequently for a better femoral footprint view during reconstruction of anterior cruciate ligament (ACL). A comprehensive evaluation of possible consequences of using the CTP performing an ACL reconstruction does not exist. Our hypothesis was that the use of CTP for ACL reconstruction does not lead to a higher rate of complications or clinically evident radiological abnormalities. In total, 141 patients were prospectively evaluated, 69 underwent ACL reconstruction using a standard high medial portal as view portal, and 72 where a CTP was used. Clinical evaluation, Kujala's score, patellar height, and magnetic resonance (MR) abnormalities were evaluated up to 1-year follow-up. Clinical complications were reported in 16 cases with no statistically significant differences between the two groups. The group 2 had significantly more MR abnormalities (p = 0.048), but the differences in MR alterations do not have any clinical repercussion even in a sports-active population. No differences were found between the groups in Kujala's score, time to return to work, and sport or patellar height. The overall mean preoperative Caton-Deschamps Index decreased significantly (p = 0.034) postoperatively. Postoperative patellar height seems to slightly decrease after ACL reconstruction regardless of the kind of the portals used intraoperatively and the initial patellar height. Nevertheless, this change in patellar height does not influence the postoperative outcome. CTP used for ACL reconstruction does not lead to significative major clinical complications.

Changes in patellar height and patellofemoral alignment following double level osteotomy performed for osteoarthritic knees with severe varus deformity

PurposeTo evaluate the effect of double level osteotomy (DLO), a combination of a lateral closed distal femoral osteotomy (LCWDFO) and medial opening wedge high tibial osteotomy (MOWHTO), on patellar height and patellofemoral alignment as compared to those of isolated MOWHTO. MethodsTwenty-six consecutive knees in 26 patients who underwent DLO (DLO group) constituted the study population. For comparative purpose, a control cohort (N: 26) matched for age, sex, and body mass index with the study group were selected from the patients who underwent isolated MOWHTO with an opening gap of more than 10 mm during the same period (MOWHTO group). Patellar height and patellofemoral alignment were assessed on radiographs preoperatively and at 2 years after surgery. For the patellar height, following parameters were measured on a lateral radiograph: Modified Insall-Salvati Index (mISI), modified Caton–Deschamps Index (mCDI), and modified Blackburne-Peel Index (mBPI). In the assessment of patellofemoral alignment, lateral patellar tilt (LPT) and lateral patellar shift (LPS) were measured on a skyline view. The measured values were statistically compared using the Student’s t-test. ResultsIn the DLO group, the patellar height measured by mCDI and mPBPI significantly decreased after surgery. As regards the patellofemoral alignment, LPT significantly decreased with no significant postoperative change detected for LPS. When the amounts of postoperative changes in radiological indices were compared between the DLO and isolated MOWHTO groups, no significant differences were detected for all parameters. ConclusionDLO induced reduction in patellar height and decreased lateral patellar tilt. Those changes in patellar position and orientation were similarly observed in isolated MOWHTO knees. Although DLO is specifically indicated for knees with severe varus deformity, the two surgical options for correction of varus knee deformity exerted similar influences on patellofemoral biomechanics.

Femoral Tunnel Fixation for Medial Patellofemoral Ligament Reconstruction in the Growing Patient is Safe for Future Growth

Objectives:Medial patellofemoral ligament (MPFL) reconstruction has been shown to be a successful treatment for patients with recurrent patellar instability and is increasingly used to treat skeletally immature patients. The purpose of this study is to compare radiographic parameters prior to and following an MPFL reconstruction with femoral tunnel fixation in the skeletally immature patient to investigate potential effects on the physis and future growth.Methods:Skeletally immature patients undergoing isolated MPFL reconstruction were retrospectively reviewed. Fixation of proximal MPFL was performed as a femoral socket using Schottle’s point with the entry approximately 5 mm distal to the physis. Patients with open growth plates and 1-year postoperative standing alignments were included. Radiographic measures of patellar tilt, patellar height, patellar subluxation, and trochlear dysplasia were compared pre-operatively and post-operatively on the operative limb. Pre- and post-operative coronal alignment and limb length measurements were compared between the operative and non-operative limbs.Results:Nineteen skeletally immature patients with an average age of 11.6 years (range 5-15 years old) underwent isolated MPFL reconstruction. The average follow-up time was 24 months. No significant differences were found between the change in femur (0.49 mm, p=0.526) or total limb length (1.08 mm, p=0.241) when comparing the operative to the non-operative limb, with an average of 47 mm of growth in the operative limb seen during the time period. There was no significant difference in the change in LDFA between operative and non-operative limb as well as symmetric changes noted in the mechanical axis. The change in patellar tilt on the operative limb was found to be significant (12.78°, p=0.030), and the change in patellar height by Caton-Deschamps approached significance (0.08mm, p= 0.077). No significant difference was found with trochlear dysplasia measures.Conclusion:The present study suggests MPFL reconstruction with femoral tunnel fixation is safe and does not result in growth disturbance in skeletally immature patients.Table 1.Mean Tegner Activity Score based on type of posterolateral tibial plateau impaction fractures. N Tegner Score STD No fracture1986.02.1Type I995.52.1Type IIA515.41.9Type IIB204.71.6Type IIIA114.52.5Type IIB214.91.9STD-Standard deviation

FEMORAL TUNNEL FIXATION FOR MEDIAL PATELLOFEMORAL LIGAMENT RECONSTRUCTION IN THE GROWING PATIENT IS SAFE FOR FUTURE GROWTH

Background:Medial patellofemoral ligament (MPFL) reconstruction has been shown to be a successful treatment for patients with recurrent patellar instability and is increasingly used to treat skeletally immature patients.Purpose:The purpose of this study is to compare radiographic parameters prior to and following an MPFL reconstruction with femoral tunnel fixation in the skeletally immature patient to investigate potential effects on the physis and future growth.Methods:Skeletally immature patients undergoing isolated MPFL reconstruction were retrospectively reviewed. Fixation of proximal MPFL was performed as a femoral socket using Schottle’s point with the entry approximately 5 mm distal to the physis (Figure 1). Patients with open growth plates and 1-year post-operative standing alignments were included. Radiographic measures of patellar tilt, patellar height, patellar subluxation, and trochlear dysplasia were compared pre-operatively and post-operatively on the operative limb. Pre- and post-operative coronal alignment and limb length measurements were compared between the operative and non-operative limbs.Results:Nineteen skeletally immature patients with an average age of 11.6 years (range 5-15) underwent isolated MPFL reconstruction. The average follow-up time was 24 months. No significant differences were found between the change in femur (0.49 mm, p=0.526) or total limb length (1.08 mm, p=0.241) when comparing the operative to the non-operative limb, with an average of 47 mm of growth in the operative limb seen during the time period. There was no significant difference in the change in LDFA between operative and non-operative limb as well as symmetric changes noted in the mechanical axis. The change in patellar tilt on the operative limb was found to be significant (12.78°, p=0.030), and the change in patellar height by Caton-Deschamps approached significance (0.08mm, p= 0.077). No significant difference was found with trochlear dysplasia measures.Conclusion:The present study suggests MPFL reconstruction with femoral tunnel fixation is safe and does not result in growth disturbance in skeletally immature patients.Figure 1.Fluoroscopic images of the femoral placement of the bone tunnel for the medial patellofemoral ligament reconstruction in a 13 year old male utilizing Schottle point and remaining distal to the physis. (A) Lateral view of the knee (B) Notch view of the knee in order to confirm position of the guide pin distal to the physis posteriorly.

Failures of Realignment Osteotomy

Abstract Realignment osteotomies about the knee, consisting of proximal tibial and distal femoral osteotomies, are excellent methods for addressing mechanical axis deviation in the setting of unicompartmental knee osteoarthritis, ligament insufficiency, meniscus deficiency, and/or focal cartilage defects. These procedures, however, are not without complications. Complications encountered with theses osteotomies include cortical hinge fracture, tibial slope alterations, changes in patellar height, vascular injuries, and various early and late postoperative complications, including delayed unions and nonunions. This current concept article reviews the etiology, diagnosis, and management strategies for various complications related to high tibial and distal femoral osteotomies. In addition, technical strategies are provided for how to recognize and revise failed osteotomies in the setting of delayed unions and nonunions.