The management of superior dislocation of the patella with interlocking osteophytes--an update on a rare problem

The Novelty of Orthopedic Rehabilitation After Conservative Management for Patellar Dislocation With Partial Tear of Medial Meniscus and Early Osteoarthritis in a 31-Year-Old Female

Primary patellar dislocation or first-time patellar dislocation is the second most frequent cause of knee injuries which overall accounts for about 3% of other knee injuries. The patellofemoral joint is formed by the patella connecting to the femoral trochlea and creates both static and dynamic structures of the knee. There are basically three types of patellar dislocation: superior, lateral, and medial. The lateral dislocation is the most frequent one. Females are more vulnerable and are at higher risk than males. Muscular weakness or muscular imbalance leads to patellar instability, and ultimately to dislocation. The recurrence rate after primary patellar dislocation is 15-60%. This case report is of a 31-year-old female with patella dislocation with a medial meniscal tear and a case of early osteoarthritis for whom we planned goal-oriented physiotherapy rehabilitation week-wise and progressed every week. The assessment was taken before and after physiotherapy rehabilitation. The patient was managed conservatively with a long knee brace, and physiotherapy started after one month. Due to prolonged immobilization, the patient suffered from quadriceps muscle atrophy. The physiotherapist focused on biomechanism and got the expected results in pain reduction, regaining strength, and improving range of motion, and the patient was able to walk properly without taking any support after rehabilitation.

Superior Patellar Dislocation Reduced by Intra-articular Injection: A Case Report and Review of Literature

CASE

A 53-year-old woman presented with a locked knee after an atraumatic hyperextension episode. Imaging showed an anterior tilt of the patella hinging over the superior trochlear margin, consistent with a superior patellar dislocation. The patella spontaneously reduced on an intra-articular injection with 15 mL of lidocaine in normal saline, after which she was able to actively range her knee.

CONCLUSION

Superior patellar dislocations are rare and usually result from a sudden forced contraction of the quadriceps, trapping the patella over superior trochlear osteophytes. Reduction is possible through an intra-articular local anesthetic injection, without manipulation of the patella.

[A rare cause of an acutely locked knee joint: superior patellar dislocation]

The case of a 56-year-old male patient with locking of the knee in extension without trauma is presented. Patient history, clinical examination and radiographs confirmed a superior dislocation of the patella. Closed reduction led to full weight bearing with free range of motion without further complaints. Knowledge of this uncommon cause of a locked knee joint leads to immediate treatment avoiding complex imaging modalities, such as computed tomography (CT) or magnetic resonance imaging (MRI). No further treatment was necessary in the majority of the cases published in the literature.

Superior Dislocation of the Patella Treated by Closed Reduction: A Rare Case Report and Review of the Literature

Superior dislocation of the patella is a rare condition. We report a 70-year-old gentleman with his patella lower pole osteophyte interlocked with the anterior femoral condyles after hyperextension. The patella was reduced successfully with proper reduction technique under sedation. The active range of movement ranged from full extension to 120-degree flexion a few minutes after reduction. He walked unaided afterwards. There was no knee problem in two years of follow-up. On reviewing the literature, only 20 cases were reported till year 2007 worldwide and 19 cases could be treated by closed reduction with or without sedation.

Spontaneous superior patellar dislocation in young age: case report and reduction technique

Superior patellar dislocation is a very rare pathology, which happens in middle age. We report a case of spontaneous superior patellar dislocation, which occurred at 30 years of age. Differential diagnosis is patellar tendon rupture, which could be reliably excluded by clinical examination and radiographs. Reduction manoeuvres should be tried with diluted intra-articular local anaesthetic for hydrodilatation to gain mechanical advantage. Splinting the knee in gentle flexion is recommended if general anaesthetic is employed. Recurrent dislocation or osteochondral fractures warrants surgical treatment.

Superior dislocation of the patella: a pathognomonic finding and review of literature

A 59-year-old woman with a painful right knee that became locked in extension after a trivial trauma was seen at the emergency room. This was caused by unloaded hyperextension in bed. She was diagnosed with a superior dislocation of the patella. A closed reduction was performed, but a recurrent episode was seen within a week. An arthroscopy was performed, in which the causative osteophytes were removed. In the 12-month follow-up after treatment, no recurrence was seen. A superior dislocation of the patella is caused by patellofemoral osteophytes that interlock. This can cause a degenerative knee to become locked in extension. Beside interlocking osteophytes of the patella and the distal femur, the superior part of the patella is tilted away from the femur. This is caused by the pull of the patella tendon and the simultaneous relaxation of the quadriceps tendon. This is a pathognomonic finding on radiographs that, to the best of our knowledge, has been identified but not been appreciated as such in previous reports. As illustrated in this report, a superior dislocation of the patella can easily be recognized on physical examination and radiographic imaging alone when familiar with the specific abnormalities. This will reduce unnecessary diagnostic imaging studies and delay in treatment. This case report illustrates a recurrent case of superior dislocation of the patella. We summarize and evaluate previous reports, discuss trauma mechanisms, physical examination, classification, and treatment including recurrent cases. After reading this case report the reader will be able to diagnose a superior dislocation of the patella with near certainty on physical examination and radiographic imaging of the knee alone.

Superior Patellar Dislocation Misdiagnosed as Patellar Tendon Rupture: The Value of Ultrasonography

Superior dislocation of the patella with intact patellar tendon is a rare condition. Most cases in literatures were diagnosed by clinical examination and plain radiography; however there are many cases that were misdiagnosed as patellar tendon rupture. In this case, we demonstrate the use of ultrasound for diagnosis of superior dislocation of the patella in the emergency department. We also include a literature review of similar cases and discuss the advantages of different types of imaging for diagnosis in this condition.

Locked Superior Patellar Dislocation

Superior dislocation of the patella is a rare cause of knee locking, with fewer than 20 cases reported in the English literature. The vast majority of traumatic or even atraumatic knee locking cases are due to such varied conditions as meniscal tears, osteochondral lesions, osteoarthritis, and ligamentous tears. A careful examination with proper radiographic imaging must be undertaken to properly evaluate patients who present with a locked knee, as they may have interdigitating patellofemoral osteophytes. An unusual case of a locked knee secondary to interlocking osteophytes between the femoral condyle and the inferior pole of the patella without a history of trauma is presented. The authors show how local sedation and gentle reduction are usually sufficient treatment, and that the vast majority of patients with this injury quickly return to their baseline functional level without the need for general sedation or surgical treatment.

Superior Dislocation of the Patella in a Young Woman without Osteophytes: A Case Report

Superior dislocation of the patella without patellar ligament injury is an extremely rare condition. A review of the English-language literature found only 23 reported cases. In addition, the primary factor for dislocation in most of these cases was considered to be osteophytes in the inferior pole of the patella and the anterior surface of the femoral condyle; only 1 case had no osteophytes. We treated a 19-year-old woman who sustained a painful locking of the left knee after colliding with a friend. Plain radiography and computed tomography showed superior-lateral dislocation of the patella and an interlocking between notches in the inferior pole of the patella and the anterior surface of the femoral condyle. Closed reduction without sedation was performed without difficulty, and the patient was able to walk home without pain. After 1 week, the knee was without problems. The patient had no osteophytes in the knee and had no other common risk factors, such as patella alta, ligamentous laxity, genu recurvatum, and paralytic disorders. After a comparison with previously reported cases of superior patella dislocation, we concluded that the primary factor in the present case might have been a different condition.

Superior patellar dislocation: the value of clinical examination and radiological investigation

A 57-year-old obese woman with a history of osteoarthritis presented with an acutely painful left knee and an inability to bear weight following a twisting injury. The initial diagnosis in A&E was a ruptured patellar tendon. A more thorough clinical examination revealed a high-riding patellar with the knee hyper-extended and a patellar dimple, consistent with superior patellar dislocation. The diagnosis was confirmed with imaging and the patient successfully underwent closed reduction. She re-presented 2 months later with ipsilateral knee pain after climbing a step. The initial diagnosis was quadriceps tear and ultrasound confirmed a partial tear in proximal vastus medialis. She was discharged home with analgesia and splinting of the leg. Subsequent MRI demonstrated severe tricompartmental degenerative changes in the left knee, the tear in vastus medialis noted on ultrasound with disruption to the medial capsular structures in keeping with lateral subluxation of the knee.

Locked knee from superior dislocation of the patella-diagnosis and management of a rare injury

Knee locking is often caused by a torn meniscus or loose body. A rare cause of knee locking is a superior dislocation of the patella following trauma with less than 20 reported cases in the English literature. An unusual case of a locked knee secondary to interlocking osteophytes between the medial femoral condyle and the inferior pole of the patella without any history of trauma is presented.

Superior dislocation of the patella: a case report

Background

Superior dislocation of the patella is an uncommon condition that mainly occurs in knees with a high patella and medial femorotibial degenerative arthritis. There are no previous reports of this condition occurring in association with tibial valgus osteotomy. Case report: We report the case of a patient in whom vertical dislocation recurred twice at 4 months after tibial valgus osteotomy. To avert additional recurrence or new dislocations, the patient was treated surgically to remove the existing osteophytes. Conclusions: An arthroscopic approach was decided because of the lower associated morbidity and good results with this technique compared to open surgery.

Superior dislocation of patella in a rugby player: an update on a extremely rare condition and review of literature

Superior dislocation of patella without patellar ligament injury is a rare clinical condition: hence often brings diagnostic dilemma for Emergency physician. Only few cases have been reported in the literature and all of them had coexistant patellofemoral joint osteoarthritis. We present such dislocation in a 34-years old rugby player after a fall without any preexisting arthrosis in the knee. This case report aims to highlight a rare condition and subtle radiological findings while assessing acute knee pain. Differences of this dislocation with vertical type of intraarticular dislocation have been discussed.