Technical Considerations for an Anteromedializing Tibial Tubercle Osteotomy

Background: Tibial tubercle osteotomy and distal realignment allows for adjustment to the patellofemoral articulation in order to improve patellar tracking and redistribute patellar contract pressures. Indications: A healthy, active 39-year-old woman status post right knee tibial tubercle osteotomy presented with >2 years of patellar instability symptoms in the left knee. Imaging revealed a tibial tubercle to trochlear groove (TT-TG) distance of 21 mm and patellar tendon lateral trochlear ridge (PT-LTR) distance of 14 mm. Technique Description: After knee arthroscopy is performed, an open incision is made along the inferomedial patellar tendon. Two pilot holes are created before a sagittal saw is used to make the tibial tubercle osteotomy, before completing it with an osteotome. Anteromedialization and/or distalization of the osteotomy is performed relative to templated values in order to improve patellar articulation. After correction, 3 bicortical screws are placed to achieve stable fixation. Results: There were no immediate complications following surgery. Surgical management led to improvement of the patient’s patellofemoral pain, which allowed return to prior baseline level of function. Discussion/Conclusion: The preferred technique for an anteromedialzing tibial tubercle osteotomy is presented. An anteromedializing tibial tubercle osteotomy is an effective surgical option for patients with evidence of patellar maltracking or central or lateral patellar chondromalacia whom have failed conservative management. This case demonstrates the efficacy of an anteromedializing tibial tubercle osteotomy to provide pain relief by improving patellar tracking and offloading patellar contact pressures on areas of prominent chondral wear.

Effectiveness of kinesio taping on functional outcomes in patellofemoral pain syndrome patients with abnormal patellar tracking

This study aimed to compare quadriceps strength, muscle reaction time, and patient-reported outcomes in PFPS patients with abnormal patellar tracking with and without kinesio taping. Twenty patients with PFPS who applied kinesio taping and 19 who did not were included. Muscle strength and reaction time (acceleration time; AT) were evaluated using an isokinetic device. Patient-reported outcomes were measured using the visual analog scale (VAS) and Kujala anterior knee pain scale (AKPS). Conservative therapeutic exercises were performed in both groups. In each group, all parameters (quadriceps strength: p < 0.001, quadriceps AT: p < 0.001, patient-reported outcomes, including VAS: p < 0.001, AKPS: p < 0.001 for taping group; quadriceps strength: p < 0.001, quadriceps AT: p < 0.001, patient-reported outcomes, including VAS: p < 0.001, AKPS: p < 0.001 for non-taping group), improved after intervention in the symptomatic knees. However, there were no significant differences in quadriceps strength and AT, and patient-reported outcomes in the symptomatic knees between the groups with and without kinesio taping (all p > 0.05). In patients with PFPS with abnormal patellar tracking, the present study shows that kinesio taping seems to be ineffective for quadriceps strength and muscle reaction time, and patient-reported outcomes. Further studies are needed to clarify the effects of kinesio taping without conservative therapeutic exercise in PFPS patients with abnormal patellar tracking.

Intraoperative patellar maltracking and postoperative radiographic patellar malalignment were more frequent in cases of complete medial collateral ligament release in cruciate-retaining total knee arthroplasty

Background Patellar maltracking after total knee arthroplasty (TKA) can lead to significant patellofemoral complications such as anterior knee pain, increased component wear, and a higher risk of component loosening, patellar fracture, and instability. This study was to investigate the preoperative and operative variables that significantly affect patellar tracking after cruciate-retaining TKA. Methods We studied 142 knee joints in patients who had undergone TKA: the knees were dichotomized based on postoperative patellar tracking, which was evaluated on patellar skyline, axial-projection radiographs: group 1, normal patellar tracking (lateral tilt ≤ 10° and displacement ≤ 3 mm) and group 2, patellar maltracking (lateral tilt > 10° or displacement > 3 mm). The patients’ demographic data and clinical and radiographic measurements obtained before and after surgery were compared between the two groups. Results Preoperative lateral patellar displacement was greater (4.1 ± 2.6 mm vs. 6.0 ± 3.5 mm), as was the frequency of medial collateral ligament (MCL) release (3/67 vs. 24/75) in group 2 than in group 1 (p < 0.001 and p < 0.001, respectively). The distal femur was cut in a greater degree of valgus in group 1 than in group 2. (6.3 ± 0.8° vs. 6.0 ± 0.8°) (p = 0.034). Conclusions Complete release of the MCL during surgery was associated with patellar maltracking (logistic regression: p = 0.005, odds ratio = 20.592). Surgeons should attend to patellar tracking during surgery in medially tight knees. Level of evidence Retrospective comparative study, level III.

Comparison between Single- and Multi-Radius Prostheses Used in Modified Kinematically Aligned Cruciate-Retaining Total Knee Arthroplasty

Kinematically aligned total knee arthroplasty (TKA) has gained interest for achieving more favorable clinical outcomes than mechanically aligned TKA. The present study aimed to compare the clinical outcomes of kinematically aligned TKAs using single-radius (SR) or multi-radius (MR) prostheses. Sixty modified kinematically aligned cruciate-retaining TKAs (30 SR and 30 MR type prostheses) were performed in patients with varus-type osteoarthritis using a navigation system. Intraoperative and postoperative patellar tracking were compared between the two groups. Trochlea shape was also compared between the prostheses and preoperative native anatomy using three-dimensional simulation software. Total 2 years postoperatively, the range of motion and 2011 Knee Society Scores (KSS) were compared between the two groups. There were no differences in patellar maltracking including patellar lateral shift and tilt between the two groups; however, the ratio of intraoperative lateral retinacular release for adjusting patellar tracking was significantly higher in the MR group than in the SR group. Lateral and medial facet heights in both prostheses were understuffed compared with native knee anatomy, while the deepest point of the trochlear groove was significantly more medial in the MR group. The postoperative clinical outcomes showed no significant differences between the two groups. In conclusion, modified kinematically aligned TKAs using a SR or MR prosthesis showed no significant differences in clinical outcomes or patellar tracking when appropriate lateral retinacular release was performed.