Poster 269: 4-in-1 Quadricepsplasty for Habitual and Fixed Lateral Patellar Dislocation in Children

Objectives: Habitual and fixed patellar dislocations represent extreme forms of instability can lead to significant functional loss. The underlying complex pathoanatomy a laterally positioned shortened extensor mechanism pose challenges in its management. first purpose the study was evaluate presence these anatomic risk factors habitual dislocations. Conservative treatment options including bracing, physical therapy activity modifications are not sufficient correct or compensate for Since primary pathology is positioned, externally rotated quadriceps mechanism, cornerstone an anterior repositioning lengthening known as quadricepsplasty. second our clinical outcomes 4-in-1 quadricepsplasty (wide lateral releases, Insall’s proximal tube realignment, Roux- Goldthwait tendon hemi-transfer, step-wise lengthening) stabilization dislocation. Methods: In retrospective study, all patients with dislocation who underwent had minimum 2 year follow-up, were identified. Preoperative MRIs evaluated factors. Trochlear dysplasia determined based on trochlear depth measurements axial MRI, < 3 mm considered abnormal. Patellar height calculated using Caton-Deschamps index sagittal section; >1.2 be Tibial tubercle lateralization Tubercle groove distance (TTTG) MRI; >20 pathologic. Lateral tilt defined angle between widest portion patella line tangential posterior surface femoral condyles view > 20° prescence any effusion, bone bruises, osteochondral fracture, chondral lesions also noted. procedure performed through single 15 cm midline knee incision. Wide releases arthrotomy after release tethers aspect subcutaneous tissues, iliotibial band, retinaculum, vastus lateralis tendon. retinaculum cut coronal Z-fashion achieve retinacular at time closure. A medial repositioned trochlea. Next, by transposition half Then flap which includes medialis muscle brought over sutured enclosing ‘tube’. parapatellar modification ‘tube’ realignment procedure. Finally, sequentially lengthened. flexed 90° side new site attachment more compared normal insertion; this lengthens mechanism. formal Z-lengthening seldom required if flexion could achieved repositioned. Postoperatively, long leg cast applied 3-4 weeks. Operative notes reviewed collect detailed information related Postoperative course, complications, Patient reported collected validated instruments Pedi-IKDC, HSS-Pedi FABS score, Banff Instability Index (BPII) Kujala score KOOS score. Results: 17 knees (12 patients) formed cohort. 12 5 Mean age 9.7 years. 6/17 (35.3%) associated syndromes. On most common factor present 15/17 (88.2%) knees. 13/17 (76%) At mean follow-up 39.3 months, Pedi-IKDC 88.1, HSS Pedi-FABS 15.6, BPII 78.2, 90, 93.9, overall patient satisfaction 83.3. For 3/17 (17.6%) recurrent instability, 1 postoperative stiffness that manipulation under anesthesia one superficial wound infection. Conclusions: Most during decade life. There several factors, being tilt. technique provides reliable stabilization, satisfactory results acceptable two-year 17.6% re-dislocation rate. Our results, redislocation rates patient-reported comparable previously published studies. We prefer detach from insertion / then reattaching it position once centered bent 90°. This would avoid detachment entire decrease morbidity it. other advantages physeal respecting limited resource set-up there no routine need implants, arthroscopy, fluoroscopy drilling.