A 50-year-old woman presented with iatrogenic habitual dislocation of left patella from childhood and pain from past 3 years. She recalled a childhood surgery over middle third of left thigh (incision and drainage). Few years after the surgery, she started noticing the giving way of patella and lived for 38 years without much disability. She was carrying out her daily activities without much pain or symptoms, but she was never symptom free during this period.\nPhysical examination did not reveal general joint laxity or malalignment of the lower extremity. There was a healed surgical scar over middle and lower third lateral aspect of the left thigh. Although the patella was in the femoral trochlear groove in extension, it dislocated laterally with 25 degrees of knee flexion. She complained slight discomfort by an apprehension test, but was not very painful even when dislocated. The passive lateral patellar tilt test was negative since the soft tissue attachment to the lateral border of the patella was diffusely stiff and tight. Radiological examination revealed evidence of patella alta as defined by Insall and Salvati,[] and Q angle was 18 degrees. Clinically and radiologically (Grade III Kellgren and Lawrence classification[]) tricompartmental degenerative knee arthritis was appreciated []. Preoperative Kujala score[] was 49.\nWith patient in supine position under epidural anesthesia, an anterior midline knee incision was used with paramedian arthrotomy. The lateral retinaculum was thickened while the medial retinaculum was thinned. The lateral tether is released by dividing the fibrous adhesions, which extended along the lateral intermuscular septum. The lateral patellar retinaculum and the synovium were divided and vastus lateralis was detached from the quadriceps tendon, leaving a rim of tendon for suturing.\nDue to shortening of the extensor mechanism, the patella could not be reduced. Quadriceps tendon was lengthened using V Y plasty at aponeurotic junction. Tracking was augmented with MPFL reconstruction using semi-tendinosus tendon and patellar end was fixed with 2.8 mm FASTak titanium anchor on the medial border of patella and over near isometric point on medial epicondyle of femur, which was checked under fluoroscopy. Patellar maltracking was persistent and so, it was decided to proceed with medial and distal transfer of tibial tuberosity.\nA long-leg hinged knee brace was applied with the knee in 20° of flexion and partial weight bearing with crutches for four weeks was advised, during which the patient was encouraged to do vigorous static quadriceps strengthening exercises. Knee mobilization and full weight bearing was started after four weeks. Initially patient had extensor lag of 15 degrees as she was immobilized in flexion. But after vigorous quadriceps exercises, patient improved without any extensor lag.\nAt final followup two years postoperatively, the patient was pain-free. There was no evidence of patellar maltracking or instability on detailed physical examination. Radiographs showed well reduced patella in both lateral, anteroposterior view and skyline view []. The patient's kujala knee society score 89 [] and range of motion was 0° to 90° on the left side []. Quadriceps strength was rated 4 (MRC grade).
A 51-year-old healthy bricklayer male, born in eastern Europe, presented with right-knee pain caused by a fall on the knee during his work, a few weeks prior. During his childhood, a clinically evident bilateral dislocation of patella was observed and described without the assistance of imaging. Nevertheless, the pathology was asymptomatic, and he never reported difficulty in walking. Therefore, the malformation had never been treated and the patient conducted a normal life including time served in the army.\nPhysical examination revealed that the patient could walk normally, with a very mild stumble on the right knee, which was referred as absent before the trauma. There was conspicuous muscle wasting of each thigh (particularly on the medial side, with a clear depression on the vastus medialis) and 15° of genu valgum. The patellae were lying laterally to the lateral femoral condyle with the knee in the position of full extension () and they displaced more laterally during the flexion (). The proximal tibiae were rotated outward. The knees could be extended actively against maximum resistance, with full range of motion. Both the femoral quadriceps worked as knee extensors, and their strength was 5/5. The knees showed no signs of instability or ligamentous deficiency. The right knee was painful on the lateral side, and the clinical signs were positive for pathology of the lateral meniscus.\nRoentgenograms of bilateral knees revealed small, laterally displaced patellae with slight degenerative changes in the tibiofemoral joints with subluxated tibia (). The medial joint spaces were widened. Lateral roentgenograms showed marked lateral rotation deformities of the tibiae (). A skyline view showed an increased deep of the trochlear groove, with laterally dislocated patellae forming a sort of new joint with the lateral aspect of the condyle ().\nMagnetic resonance imaging (MRI) showed a lesion with dislocation of the lateral meniscus on the right knee. On both sides, the MRI confirmed the dislocation of the patellae, a severe hypoplasia of the medial side of the femoral quadriceps, and an external rotation of the proximal tibia particularly evident on the tibial tuberosity ().\nIn order to identify a possible aetiology of the malformation, the patient underwent electromyography/electroneurography, which showed normal function of all the separate portions of the quadriceps muscles thus not explaining the origin of this malformation.\nThe clinical and the imaging findings suggested a lesion of the lateral meniscus as the probable cause of the pain. Therefore, we performed a knee arthroscopy, whose intraoperative findings confirmed the MRI. During the surgery, we performed just a selective arthroscopic meniscectomy.\nAfter the operation, the patient followed a simple protocol of rehabilitation: 15 days of relative rest with partial bearing and low-molecular-weight heparin therapy, then progressive full recover of activities. Quickly, the knee showed satisfactory improvement, with no pain in walking and a complete range of motion, as before the operation, and comparable to the other knee.\nDuring the last clinical evaluation, 12 months after surgery, written informed consent was obtained from the patient for publication of this case report and accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.