Salvage of failed patellofemoral arthroplasty due to instability: Combined medial patellofemoral ligament reconstruction, tibial tubercle osteotomy, and vastus medialis obliquus advancement - Case report and algorithm-based.

Background:Patellofemoral instability is a common problem that requires personalized treatment for each patient based on the relevant pathoanatomy. There are many ways to perform soft tissue and osteotomy procedures, and here we present our lead author's treatment algorithm, operative technique, and postoperative protocol.Indications:Medial patellofemoral ligament (MPFL) reconstruction, vastus medialis obliquus (VMO) advancement, and MPFL repair are indicated in patients with unsuccessful nonsurgical treatment after primary dislocation, those with significant osteochondral fracture, and patients with excessively high-risk factors after primary dislocation. Osteotomy is a consideration in those with elevated tibial tuberosity–trochlear groove (TT-TG) or patellar alta, while lateral retinacular lengthening is indicated for those with lateral patellar tilt.Technique Description:In part 2 of this 2-part series, we demonstrate the soft tissue components of this case, including lateral retinacular lengthening, MPFL reconstruction, VMO advancement, and MPFL repair. Lateral retinacular lengthening is shown to correct patellar tilt and allow for eversion of the patella. Once adequately lengthened, MPFL reconstruction is performed to enable a checkrein to resist lateral translation, particularly in 0° to 30° of flexion, before the patella engages the trochlea. Native MPFL imbrication is performed to further reinforce the reconstruction, and VMO advancement allows for dynamic medialization force.Results:Patients can expect improved clinical and functional outcomes with tibial tubercle osteotomy (TTO) when appropriately indicated, with reliable patellar stability and low rates of complications.Discussion/Conclusion:In patients with an elevated Caton-Deschamps Index >1.4 or TT-TG >20, TTO can lead to very high patient satisfaction, improved clinical outcomes, and low re-dislocation rates. Even in patients with a “gray” zone TT-TG of 17 to 20 mm, Level II evidence has shown improved patient-reported outcomes with the addition of TTO.Patient Consent Disclosure Statement:The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

CORR Synthesis: Can Guided Growth for Angular Deformity Correction Be Applied to Management of Pediatric Patellofemoral Instability?

Combined Tibial Tubercle Osteotomy and Medial Patellofemoral Ligament Reconstruction for Recurrent Lateral Patellar Instability in Patients With Multiple Anatomic Risk Factors

TT-TG = tibial tubercle to trochlear groove distanceMPFL = medial patellofemoral ligamentTTO = tibial tubercle osteotomyPJAC = particulated juvenile articular cartilageMACI = matrix-induced autologous chondrocyte implantationOR = operating roomIV = intravenousK-wires = Kirschner wiresCPM = continuous passive motionMRI = magnetic resonance imagingOA = osteoarthritisASA = acetylsalicylic acid (aspirin)DVT = deep vein thrombosisPPX = prophylaxisNWB = non-weight-bearingFWB = full weight-bearingPOD = postoperative day.

An isolated medial patellofemoral ligament (MPFL) reconstruction (MPFLR) has been demonstrated to be an effective treatment option in the prevention of patellar instability, but there is growing support for performing a tibial tubercle osteotomy (TTO) in patients with an elevated tibial tubercle-trochlear groove distance. The purpose of this study was to evaluate the impact of adding a TTO to MPFLR on patient reported outcomes. A retrospective review of patients who underwent MPFLR with or without TTO with a minimum of 12-month follow-up was performed. Patients in both groups were matched based on age, sex, and follow-up time. Recurrent instability (including re-dislocation and subluxation), visual analog scale (VAS) for pain score, Kujala score, and satisfaction were evaluated. There were 59 patients who underwent MPFLR with concomitant TTO performed at our institution and met our inclusion and exclusion criteria. These patients were then matched to patients undergoing isolated MPFLR based on demographics and follow-up time. The mean age was 25.0, 76.3% were female, and the mean follow-up time was 49 months. There was a significant difference in mean tibial tubercle-trochlear groove distance (19.8 ± 3.9 vs. 14.1 ± 2.8) between groups. There was no significant difference in VAS (1.48 ± 2.0 vs. 1.49 ± 2.1, p = 0.972), satisfaction (86.1% ± 24.2% vs. 81.2% ± 27.9, p = 0.311), or revision surgeries (10.2% vs. 10.2%) between groups. There was a low complication rate, excellent patient reported outcomes, and a low rate of recurrent patellar instability following TTO and MPFLR with allograft.

Background:Patellofemoral instability is a common problem that requires personalized treatment for each patient based on the relevant pathoanatomy. There are many ways to perform soft tissue and osteotomy procedures, and here we present our lead author’s treatment algorithm, operative technique, and postoperative protocol.Indications:Medial patellofemoral ligament (MPFL) reconstruction, vastus medialis obliquus advancement, and MPFL repair are indicated in patients with unsuccessful nonsurgical treatment after primary dislocation, those with significant osteochondral fracture, and patients with excessively high-risk factors after primary dislocation. Osteotomy is a consideration in those with elevated tibial tuberosity–trochlear groove or patellar alta, while lateral retinacular lengthening is indicated for those with lateral patellar tilt.Technique Description:In part 1 of this 2-part series, diagnostic arthroscopy and tibial tubercle osteotomy (TTO) are demonstrated. In this patient case, both distalization and medialization are required. Diagnostic arthroscopy is performed, and in particular, the important role of the superomedial viewing portal is shown to assess patellar tracking and trochlear dysplasia better. Exposure and osteotomy of the tibial tubercle are shown, including predrilling unicortical holes in the planned osteotomy before completion with osteotomes. The distalization is measured and performed, and the tubercle is translated both medially by 1 cm and distally by 2 cm.Results:Patients can expect improved clinical and functional outcomes with patellar stability and low rates of complications.Discussion/Conclusion:PFI requires a patient-specific approach that takes into account the patient’s relative pathoanatomy and a surgical plan aimed at addressing each component. Multiple known risk factors can help predict the risk of recurrent instability and guide patient-informed decision-making. Consistent indications and technique can lead to very high patient satisfaction and improved clinical outcomes.Patient Consent Disclosure Statement:The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Background: No clear guidelines or widespread consensus has defined a threshold value of tibial tuberosity–trochlear groove (TT-TG) distance for choosing the appropriate surgical procedures when additional tibial tuberosity osteotomy (TTO) should be added to augment medial patellofemoral ligament (MPFL) reconstruction for recurrent patellar instability. Purpose: To compare the clinical outcomes between MPFL reconstruction and MPFL reconstruction with TTO for patients who have patellar instability with a TT-TG distance of 15 to 25 mm. Study Design: Cohort study; Level of evidence, 3. Methods: We retrospectively analyzed 81 patients who underwent surgical treatment using either MPFL reconstruction or MPFL reconstruction with TTO for recurrent patellar instability with a TT-TG distance of 15 to 25 mm; the mean follow-up was 25.2 months (range, 12.0-53.0 months). The patients were divided into 2 groups: isolated MPFL reconstruction (iMPFL group; n = 36) performed by 2 surgeons and MPFL reconstruction with TTO (TTO group; n = 45) performed by another 2 surgeons. Clinical outcomes were assessed using the Kujala score, Knee injury and Osteoarthritis Outcome Score, and Tegner activity score. Radiological parameters, including patellar height, TT-TG distance, patellar tilt, and congruence angle were compared between the 2 groups. Functional failure based on clinical apprehension sign, repeat subluxation or dislocation, and subjective instability and complications was assessed at the final follow-up. We also compared clinical outcomes based on subgroups of preoperative TT-TG distance (15 mm ≤ TT-TG ≤ 20 mm vs 20 mm < TT-TG ≤ 25 mm). Results: All of the clinical outcome parameters significantly improved in both groups at the final follow-up (P < .001), with no significant differences between groups. The radiological parameters also showed no significant differences between the 2 groups. The incidence of functional failure was similar between the 2 groups (3 failures in the TTO group and 2 failures in the iMPFL group; P = .42). In the TTO group, 1 patient experienced a repeat dislocation postoperatively and 2 patients had subjective instability; in the iMPFL group, 2 patients had subjective instability. The prevalence of complications did not differ between the 2 groups (P = .410). In the subgroup analysis based on TT-TG distance, we did not note any differences in clinical outcomes between iMPFL and TTO groups in subgroups of 15 mm ≤ TT-TG ≤ 20 mm and 20 mm < TT-TG ≤ 25 mm. Conclusion: MPFL reconstruction with and without TTO provided similar, satisfactory clinical outcomes and low redislocation rates for patients who had patellar instability with a TT-TG distance of 15 to 25 mm, without statistical difference. Thus, our findings suggest that iMPFL reconstruction is a safe and reliable treatment for patients with recurrent patellar dislocation with a TT-TG distance of 15 to 25 mm, without the disadvantages derived from TTO.

Background:Patellar instability remains a challenging problem for both the patient and surgeon. Medial patellofemoral ligament (MPFL) repair has historically had poor results, and due to this, there is currently a trend toward reconstruction.Purpose/Hypothesis:This study was undertaken to investigate experience with repair versus reconstruction of the MPFL using a multifactorial treatment algorithm approach. Our hypothesis was that there will be no significant difference in outcome scores between patients in the MPFL repair and reconstruction groups.Study Design:Cohort study; Level of evidence, 2.Methods:A total of 24 patients with recurrent (≥2) lateral patellar dislocations were included. All had failed nonoperative treatment for more than 6 months, and all were observed for a minimum of 2 years. First, magnetic resonance imaging (MRI) was used to find the location of the MPFL tear. A tilt test was used to determine whether a lateral retinacular lengthening was required to allow the patella to have neutral tilt. If the MRI showed a tibial tubercle–trochlear groove (TT-TG) distance greater than 20 mm, a tibial tubercle osteotomy (TTO) was recommended. An MPFL reconstruction was performed if the entire ligament was inadequately visualized on MRI or if it was torn from both insertion sites. Failure was defined as recurrent lateral patellar instability after surgery. As a secondary outcome measure, Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm score, and Tegner score were calculated.Results:All patients were evaluated with a mean follow-up of 51 months (range, 25-79 months). Sixteen patients initially underwent MPFL repair, 8 underwent reconstruction, and 3 also underwent TTO. MPFL reconstructions were performed in all patients who underwent TTO. One MPFL repair was to the anatomic femoral origin and 15 were to the patellar insertion corresponding to the site of tearing on MRI. A lateral retinacular lengthening was performed in 21 patients. There was 1 failure in the repair group (6%) and none in the reconstruction group. However, the patient who failed had a TT-TG distance of 26 mm but refused a TTO. She subsequently underwent revision with a TTO and MPFL reconstruction and did not have any further instability events. There were no significant differences between groups for any of the secondary outcome scores.Conclusion:Using an algorithm-based approach, MPFL repair or reconstruction may lead to clinically acceptable results at 2-year follow-up.

Patellofemoral instability is common in adolescent patients and is frequently associated with increased tibial tuberosity-trochlear groove (TT-TG) distances. Medial patellofemoral ligament (MPFL) reconstruction is a standard treatment; however, the role of tibial tubercle osteotomy (TTO) remains debated. A retrospective chart review was performed of patients with TT-TG distances ≥20mm who underwent MPFL reconstruction between 2012 and 2022, with a minimum 2-year follow-up. Patients were stratified into 2 cohorts: MPFL with TTO and MPFL without TTO. Demographic, radiographic, and operative variables were collected, including TT-TG, Insall-Salvati ratio, trochlear dysplasia index (TDI), and tibial tubercle-posterior cruciate ligament (TT-PCL). Outcomes included complications, recurrent instability, and patient-reported outcomes (PROs): Single Assessment Numeric Evaluation (SANE), Kujala, pain, and satisfaction. Thirty patients (31 knees) were analyzed (15 TTO, 16 non-TTO). The cohort's mean age was 15.3 years, with a mean follow-up of 5.7±2.8 years (TTO) and 4.8±2.1 years (non-TTO) ( P =0.40). The TTO cohort had higher TT-TG distances (22.6±2.3mm vs. 20.8±0.8mm; P =0.01), elevated Insall-Salvati ratios (1.7±0.2 vs. 1.5±0.3; P =0.04), and longer tourniquet times (83.4±29.0 vs. 56.9±22.1min; P =0.01). TDI and TT-PCL were not significantly different. No differences were observed in PROs: SANE (84.3±9.3 vs. 86.8±7.2; P =0.42), Kujala (91.4±8.0 vs. 88.5±10.9; P =0.48), pain (1.2±1.6 vs. 1.6±2.1; P =0.88), or satisfaction (9.1±1.1 vs. 9.4±0.8; P =0.56). Complication rates ( P =1.0), recurrent instability ( P =0.64), return-to-sport ( P =1.00), and revision rates ( P =0.39) were similar between groups. The addition of TTO to MPFL reconstruction in adolescents with elevated TT-TG distances did not result in significant differences in complications, PROs, or recurrent instability compared with MPFL alone. TTO may not be required in all cases and should be reserved for select patients based on individual anatomic and clinical factors.

ObjectivesAn isolated medial patellofemoral ligament (MPFL) reconstruction (MPFLR) has been demonstrated to be an effective treatment option in the prevention of patellar instability, but there is growing support for performing a tibial tubercle osteotomy (TTO) in patients with an elevated tibial tubercle-trochlear groove distance. The purpose of this study was to evaluate the impact of adding a TTO to MPFLR on patient-reported outcomes. MethodsA retrospective review of patients who underwent MPFLR with or without TTO with a minimum of 12-month follow-up was performed. Patients in both groups were matched based on age, gender, and follow-up time. Recurrent instability (including redislocation and subluxation), visual analogue scale (VAS) score, Kujala score, and satisfaction were evaluated. ResultsThere were 59 patients who underwent MPFLR with concomitant TTO performed at our institution and met our inclusion and exclusion criteria. These patients were then matched to patients undergoing isolated MPFLR based on demographics and follow-up time. The mean age was 25.0 years, 76.3% were female, and the mean follow-up time was 49 months. There was a significant difference in mean tibial tubercle-trochlear groove distance (19.8 ± 3.9 vs. 14.1 ± 2.8) between groups. There was no significant difference in VAS (1.48 ± 2.0 vs. 1.49 ± 2.1, p = 0.972), satisfaction (86.1% ± 24.2% vs. 81.2% ± 27.9, p = 0.311) or revision surgeries (10.2% vs. 10.2%) between groups. ConclusionMatched patients undergoing MPFLR with TTO compared with isolated MPFLR demonstrate no statistically significant difference in patient-reported outcomes, levels of pain, and satisfaction postoperatively. Furthermore, the addition of a TTO does not increase the risk of further surgery or complications. Level of evidenceIII, retrospective comparative study.

Objectives: The medial patellofemoral ligament (MPFL) is the primary soft-tissue restraint against lateral patellar displacement. Surgery to address MPFL incompetence is the current gold standard for recurrent patellofemoral instability. The role of tibial tubercle osteotomy (TTO) as an adjunct to MPFL reconstruction remains controversial. Our purpose was to evaluate a cohort of patella instability patients undergoing surgical soft tissue stabilization with or without concomitant TTO. Our hypothesis was that there would be no difference between cohorts in baseline values, subjective outcome scores at final follow-up, or complication profile. Methods: Following IRB approval, retrospective review of prospectively collected data identified a consecutive cohort of patients undergoing soft tissue stabilization for recurrent patella instability, with or without concomitant TTO. Indications for TTO were at the surgeon’s discretion, including elevated TT-TG, Caton-Deschamps ratio, and/or unloading chondral lesion(s). Surgery was performed by a single sports fellowship trained surgeon. Pre-surgical and post-surgical patient reported outcomes were collected including KOOS domains, PROMIS (global health, mental health, physical function, pain interference), IKDC, SANE, and Marx scores. Complications requiring re-operation (infection, stiffness, recurrent instability) were recorded. Results were analyzed statistically. Results: The cohort was comprised of 87 patients (95 knees), with 25 males (28.7%) and 62 females (71.3%). The MPFL-TTO cohort had 32 patients (38 knees) and the MPFL-Iso had 55 patients (57 knees). The average age of the MPFL-TTO cohort was 28.3 (range 19.5-44.6) and the average age of the MPFL-Iso group was 29.8 (18.7-55.3). There was no significant difference in pre-operation outcome scores between groups (p&gt;.05). Significant improvements were seen for all KOOS domains in both patient cohorts with no significant differences detected between groups. SANE, IKDC, and PROMIS scores improved significantly with no differences detected between groups. Marx activity score at 6 months post-operatively was significantly different between the groups favoring the isolate MPFL reconstruction cohort. (MPFL-TTO 0.79 +/- 2.15 vs. 4.61 +/- 5.44 in the MPFL-Iso group (p=0.01)). In terms of complications, 4 knees in the MPFL-TTO group required further surgery (2 for stiffness, 1 for infection, and 1 for fracture) and 6 knees in the MPFL-Iso cohort required surgery (4 for stiffness, 1 for infection, and 1 for recurrent instability). Neither the overall complication rate of 4 vs. 6 (p=1) nor the recurrent instability rate of 0 vs. 1 (p=0.41) was significant. Conclusion: In a cohort of patients undergoing MPFL reconstruction, the addition of an appropriately indicated TTO appears to be both safe and effective. Both MPFL-TTO and MPFL-Iso groups demonstrated significant improvement in the majority of subjective outcome scores without major difference between groups. Marx activity scores were higher for the isolated MPFL reconstruction cohort at relatively short term follow-up. The surgical complication profile was similar between groups. Further work is needed to clearly define the role of TTO as an adjunct procedure to MPFL reconstruction.

Objective To compare the efficacy of tibial tuberosity osteotomy (TTO) combined with medial patellofemoral ligament reconstruction (MPFLR) with simple TTO in treatment of recurrent patella dislocation associated with patella alta. Methods From July 2010 to December 2015, 50 patients with recurrent patella dislocation and patella alta were included in this study. There were 15 males and 35 females with an average age of 20.6 years. These patients received surgical treatment and their clinical data were collected and retrospectively analyzed by case-control study. According to surgical methods, patients were divided into TTO group (32 cases) and MPFLR+ TTO group (18 cases). The differences between preoperative status and postoperative status were evaluated by knee function scores including Tegner, international knee documentation committee (IKDC), Kujala scores, knee injury and osteoarthritis outcome score (KOOS). Patellar stability was checked at the last follow-up visit. Results The TTO group and MPFLR+ TTO group were followed up for (50.9±17.8)months and (22.3±10.1)months, respectively. Two patients occurred recurrent dislocation in TTO group, who showed positive in both extrapolation test and extrapolation apprehension test at 0°flexions of knee. All patients in MPFLR+ TTO group did not occur recurrent dislocation, who showed negative in both extrapolation test and extrapolation apprehension test at 0°flexions of knee. There was no significant difference between preoperative and postoperative results in TTO group in Tegner score (P>0.05), KOOS scores in pain and daily life activities subdomains (P>0.05), while differences in the rest of scores were statistically significant (P<0.05). Compared with TTO group, the differences of all scores were statistically significant (P<0.05) and KOOS scores in the pain and daily life activities subdomains were significantly improved postoperatively in MPFLR+ TTO group (P<0.05). Conclusions For patients with recurrent patellar dislocation associated with patella alta, both surgical methods are found to be effective. Postoperative improvements in pain and daily life activities are less obvious in TTO. While postoperative improvements in pain and daily life activities in MPFLR+ TTO are superior to those of TTO. Key words: Patellar dislocation; Surgical procedures, operative; Patella alta

Introduction:Patellar instability is a common problem in the active pediatric and adolescent population. Medial patellofemoral ligament (MPFL) reconstruction with or without associated tibial tubercle osteotomy (TTO) are the most commonly utilized surgical treatment. Patient-Reported Outcomes Measurements Information System (PROMIS) has been shown to be a valid and reliable means to assess patient-reported outcomes in the pediatric orthopedic population. Currently, little is known about the relative recovery of isolated MPFL reconstruction compared to MPFL reconstruction with combined TTO.Purpose:To assess the outcomes of patients undergoing an isolated MPFL Reconstruction or MPFL with TTO utilizing PROMIS during post-operative recovery period.Methods:Patients undergoing patellofemoral surgery were prospectively given PROMIS assessments at each clinical visit. Inclusion criteria included a diagnosis of patellar instability, no prior MPFL procedures, <18 years old and follow up of at least 6 months. Additionally, subjects must have had a pre-operative evaluation and at least 3 FU visits within 6 months. Pediatric PROMIS domains assessed were Pain Interference and Mobility. Time points for PROMIS were labeled as pre-operative, 1 week, 1 month, 3 months, 6 months, and 1 year. Time points were then compared utilizing a mixed-linear regression model. Significance was set at p < 0.05. Ceiling or Floor Effects were present when ≥15% of study cohort had reached the maximum or minimum possible score.Results:A total of 58 patients were identified, 40 patients that underwent isolated MPFL and 18 patients that underwent MPFL + TTO. Both groups were relatively similar in terms of mean age (14.4 v. 15.3) and sex (62.5% v. 77.8% female). Changes in Mobility and Pain Interference were seen compared to baseline in both groups. For both Mobility and Pain interference, postoperative PROMIS changes were similar between isolated MPFL and MPFL + TTO groups (no significant differences at any timepoint) (Figure 1 and 2).Conclusions:MPFL reconstruction with or without TTO demonstrate improvements in PROMIS Mobility and Pain Interference after surgical treatment. The postoperative recovery of isolated MPFL reconstruction or MPFL reconstruction with TTO were very similar at all timepoints for PROMIS Mobility and Pain Interference.Figure 1:Performance of (a) Isolated MPFL Reconstruction patients and (b) MPFL with a tibial tubercle osteotomy (TTO) on the Pain Interference PROMIS domain. Time points assessed were pre-operative, 1 week, 1 month, 3 month (3 Mo), 6 month (6 Mo) and 1 year.*denotes significant improvement from pre-operative valuesFigure 2:Performance of (a) Isolated MPFL Reconstruction patients and (b) MPFL with a tibial tubercle osteotomy (TTO) on the Mobility PROMIS domain. Time points assessed were pre-operative, 1 week, 1 month, 3 month (3 Mo), 6 month (6 Mo) and 1 year.*denotes significant improvement from pre-operative values

Online Rehabilitation Protocols for Medial Patellofemoral Ligament Reconstruction With and Without Tibial Tubercle Osteotomy Are Variable Among Institutions

Background:Bipolar osteochondral allograft (OCA) transplantation is a durable option for patients with symptomatic chondral defects involving the patellofemoral joint. When due to patellar instability, treatment of bipolar lesions in the patellofemoral joint requires concomitant medial patellofemoral ligament (MPFL) reconstruction (MPFLR), and often tibial tubercle osteotomy (TTO).Indications:OCA transplantation with concomitant anteromedializing TTO and MPFLR is indicated in the setting of symptomatic Outerbridge grade 3 or 4 lesions involving both the trochlea and patella due to patellar instability.Technique Description:The tibial tubercle is osteotomized at 45°. The patellofemoral joint is exposed via a laterally based arthrotomy. Fresh OCA plugs are press-fit into the trochlea and then the patella. The MPFL is reconstructed with a hamstring allograft. The lateral retinaculum is lengthened. The tibial tubercle is medialized, anteriorized, and fixed with cannulated screws.Results:We represent a 27-year-old with symptomatic bipolar chondral defects involving the patellofemoral joint due to recurrent patellar instability. Bipolar OCA transplantation to the patellofemoral joint yields significant improvements in patient-reported outcomes, and graft survival rates are high for at least 10 years after surgery. The results of bipolar OCA transplantation are improved by concomitantly correcting any underlying anatomical pathology with TTO and MPFLR, the order of which requires thoughtful consideration.Discussion/Conclusion:OCA transplantation can be safely performed in the same surgical setting as MPFLR and TTO for patients with symptomatic patellar-instability-related bipolar patellofemoral joint chondral defects.Patient Consent Disclosure Statement:The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.