Analysis of medial unicompartmental knee arthroplasty for patients with spontaneous osteonecrosis of the knee / 中国修复重建外科杂志

Objective: To analyse the effectiveness of unicompartmental knee arthroplasty (UKA) for the patients with spontaneous osteonecrosis of the knee (SONK). Methods: Between January 2012 and December 2016, 31 patients with SONK was admitted and treated with medial UKA. All patients were examined by both plain radiography and magnetic resonance images. The patients were composed of 5 men and 26 women with an average age of 64.3 years (range, 48-79 years), and with 16 left joints and 15 right joints. The average disease duration was 14.7 months (range, 6-26 months). Preoperative visual analogue scale (VAS) was 6.00±1.15, Hospital for Special Surgery (HSS) score was 55.77±11.03, and knee range of motion (ROM) was (114.68±10.40)°. The imaging examinations showed that all the lesions were located in the medial compartment of the knee joint and there were 19 patients with Aglietti stage Ⅳ and 12 patients with Aglietti stage Ⅴ. Preoperative femorotibial angle (FTA) was (177.39±1.63)° and posterior tibial slope (PTS) was (84.05±1.39)°. Results: All the incisions healed by first intention. All patients were followed up 14-46 months (mean, 25 months). At last follow-up, VAS score was 2.06±0.72 and HSS score was 86.45±3.67, which both improved significantly when compared with preoperative scores ( t=22.73, P=0.00; t=-14.72, P=0.00). ROM was (118.06±3.80)° with no significant difference when compared with preoperative ROM ( t=-1.78, P=0.08). The X-ray films showed there was no severe adverse events, such as periprosthetic infection, aseptic loosening, bearing dislocation, and so on. At last follow- up, PTS was (85.30±1.19)° with significant difference compared with preoperative one ( t=-4.07, P=0.00); while FTA was (177.51±1.98)° with no significant difference when compared with preoperative FTA ( t=-0.38, P=0.71). Conclusion: UKA may be an optional management for SONK with minimally invasive, bone-preserving, and rapid recovery.

Clinical Characteristics and Treatment of Spontaneous Osteonecrosis of Medial Tibial Plateau: A Retrospective Case Study / 中华医学杂志(英文版)

<p><b>Background</b>In a small proportion of cases, spontaneous osteonecrosis of the knee (SONK) involves the medial tibial plateau (MT). Here, we introduced the clinical characteristics of spontaneous osteonecrosis of the MT and unicompartmental knee arthroplasty (UKA) as the favorable treatment for this situation based on a retrospective case study.</p><p><b>Methods</b>Patients with spontaneous osteonecrosis of the MT, confirmed by magnetic resonance imaging (MRI) at Guangdong Provincial Hospital of Chinese Medicine (China) from March 2015 to June 2016, were included as a case serial and analyzed retrospectively. All patients underwent Oxford Medial UKA. The characteristics of their lesions, corresponding treatment, and results of follow-up were presented. The lesion scores and grade were determined according to the criteria of Ficat and Arlet.</p><p><b>Results</b>In total, 22 patients (5 men, 17 women; mean age, 64.1 years) with spontaneous osteonecrosis of the MT were analyzed. The lesion stages assessment showed that 3 (14%) were Stage II, 10 (45%) were Stage III, 7 (32%) were Stage IV, and 2 (9%) were Stage V. In the sagittal plane, 7 (32%) were in the anterior region (MTa) and 15 (68%) were central (MTc). The lesion volume averaged 2.24 ± 0.79 cm (range: 1.57-3.08 cm). Seventeen patients (77%) had Level III posterior medial meniscus root tears (MMRTs). All the patients underwent UKA. Average follow-up was 30.0 ± 6.4 months with a range of 23.0-38.0 months. The visual analog scale score was 7.78 ± 0.67 before surgery while decreased to 2.22 ± 1.09 at the final follow-up (P < 0.001). The Hospital for Special Surgery scores of pre-/post-surgery were 65.67 ± 5.45 and 84.10 ± 4.20, respectively (P < 0.001).</p><p><b>Conclusions</b>SONK often occurs in the anterior and central tibial plateau due to abnormal stresses. Most of the patients had Level III posterior medial meniscus root tears. MRI is recommended for suspected cases to identify SONK at an early stage. The use of the Oxford Medial UKA for SONK of the MT is reliable both immediately and at follow-up.</p>

Spontaneous Osteonecrosis of the Contralateral Medial Tibial Plateau Following Spontaneous Osteonecrosis of Medial Femoral Condyle / 대한정형외과학회잡지

Spontaneous osteonecrosis of the knee (SPONK) is rare disease and most common in the medial femoral condyle. This condition presents with acute onset of pain in elderly patients, usually without a history of trauma. The exact etiology of SPONK is still debated. There are several options for the treatment according to the size, progression and site of the osteonecrosis. SPONK usually occurs in one knee. The spontaneous osteonecrosis of the medial tibial plateau is less recognized than osteonecrosis of the medial femoral condyle. And, in this case, SPONK in the medial tibial plateau of the contralateral knee followed SPONK in the medial femoral condyle, and bony destruction extended to the lateral aspect of the lateral tibial eminence from the medial tibial plateau. The best treatment has not yet been defined. This condition of the tibial side has been managed by total knee replacement resulting in a satisfactory outcome.

Medial Unicompartmental Knee Arthroplasty in Patients with Spontaneous Osteonecrosis of the Knee

BACKGROUND: We analyzed the clinical and radiologic results of patients with spontaneous osteonecrosis of the knee treated by minimally invasive medial unicompartmental arthroplasty using Oxford Uni. METHODS: We reviewed 22 knees in 21 patients which were treated for spontaneous osteonecrosis between 2002 and 2006. Patients included one male and 20 females. The mean age was 70.8 years (range, 53 to 82 years). The mean follow-up period was 70.3 months (range, 48 to 93 months). The clinical results were evaluated using the Hospital for Special Surgery (HSS) knee score and the range of motion of the knee preoperatively and at the final follow-up. Preoperative plain radiographs and magnetic resonance images were analyzed to determine the size and stage of osteonecrotic lesions. RESULTS: The mean HSS knee score was 64.3 (range, 54 to 75) preoperatively and 92.0 (range, 71 to 100) at the final follow-up. The mean preoperative flexion contracture was 8.9degrees (range, 0 to 15degrees) and 0.2degrees (range, 0 to 5degrees) at the final follow-up. The mean further flexion increased from 138.6degrees (range, 100 to 145degrees) preoperatively to 145.6degrees (range, 140 to 150degrees) at the final follow-up. Active full flexion was possible within 2 months of the operation. The squatting position was possible in 16 patients (84.2%) out of 19, except one case of bronchiectasis and one case of spine fracture. The cross-leg posture was possible in 19 patients (90.5%) out of 21. The mean tibiofemoral angle was improved from varus 0.98degrees to valgus 3.22degrees. Meniscal bearing dislocation occurred in 2 cases and femoral component loosening occurred in 1 case. CONCLUSIONS: Unicompartmental knee arthroplasty using Oxford Uni could be an alternative treatment option in spontaneous osteonecrosis of the knee.

Treatment of Spontaneous Osteonecrosis of the Knee Using the Oxford Unicompartmental Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: The purpose of this study was to evaluate the clinical and radiographic outcomes of unicompartmental knee arthroplasty (UKA) in patients with spontaneous osteonecrosis. MATERIALS AND METHODS: Between September 2002 and March 2005, 15 patients with 16 knees were treated with UKA for the treatment of spontaneous osteonecrosis. There were thirteen women and two men with a mean age of 64 years old. The clinical assessment was performed using the American Knee Society Score system. The preoperative radiography was analyzed according to the size and stage of the osteonecrotic lesion and the osteoarthritic changes. Postoperatively, the presence of new osteonecrotic lesion, loosening of the implant, subsidence and arthritic changes was recorded. RESULTS: The mean preoperative knee score and the knee function score was improved from 52.5 to 89.2 and 56.0 to 85.2, respectively. There was no new necrotic lesion in the lateral compartment, loosening of the implant, subsidence or arthritic change. CONCLUSION: UKA in patients with spontaneous osteonecrosis provided satisfactory clinical and radiological results in the short to medium term.

Spontaneous Osteonecrosis of the Knee in the Elderly over 60 Years Old / 대한정형외과학회잡지

PURPOSE: This study examined the results of treatment according to the stage and size of a spontaneous osteonecrosis lesion of the knee (SONK) in the patients over 60 years of age. MATERIALS AND METHODS: Twenty-two knees from 19 patients over 60 years of age were treated for spontaneous osteonecrosis of the knee at our institution between January, 2000, and June, 2004. The mean follow time was 20.7 months. The condylar ratios, proportion of the lesion size to the condyle were measured. The size was obtained by multiplying the values from the anteroposterior and lateral radiographs. The stages were classified radiographically, and the treatment results were analyzed according to the size and stage. Conservative treatment was performed if the ratio and size were 40% or 5.0 cm2. A paired T-test, Spearman correlation test and Wilcoxon test were used for the statistical evaluation. RESULTS: There was a higher prevalence in females (15 patients, 79%), and the mean age was 65 years (46-77 years). Bilateral involvement was observed in 3 patients. The lesions involved mainly the medial femoral condyle (21 cases, 95%). Seven cases (31%) had a condylar ratio 40%. Conservative treatments were performed in 5 cases staged radiographically as I or II and there were no significant changes in the knee scores (p=0.931). Of the 17 cases staged III and IV radiographically, conservative treatment and arthroplasty were performed in 7 and 10 cases, respectively. Seven cases, in whom conservative treatments had been performed, showed a decreased in the knee scores compared with the increased knee scores in 10 patients treated with arthroplasty (p=0.943). CONCLUSION: An accurate diagnosis and measurement of the size and staging of spontaneous osteonecrosis of knee in patients over 60 years of age is important for proper treatment. Clinically, no further progression of symptoms is visible on grade I and II spontaneous osteonecrosis of the knee after conservative treatment. However, arthroplasty improves the clinical results in patients with radiological grade III and IV osteonecrosis compared with conservative treatment.

Clinical Observations of Spontaneous Osteonecrosis of the Medial Tibial Plateau / 全日本鍼灸学会雑誌

[Objective] We analyzed the clinical findings in 5 patients with osteonecrosis in the medial condyle of the tibia. We also evaluated the usefulness of a tibial percussion test that we developed for examination of differences between the healthy and affected sides in percussion caused by knocking on the tibial rough surface.<BR>[Methods] The subjects were 5 females, who consulted our hospital with a chief complaint of gonalgia and in whom conditions such as osteonecrosis in the medial condyle of the tibia were confirmed by MRI in 4 limbs. In addition to X-p, MRI findings, medical findings by interview, and findings by physical examination were evaluated as clinical findings. Furthermore, the tibial percussion test was performed.<BR>[Results] The causes of pain in the knee joint were unclear in all patients. Pain was severe in 3 patients and marked in 2 patients. Physical examination showed marked tenderness in the medial articular gap and tenderness in the medial condyle of the tibia. In all patients, a difference in the percussion findings between the healthy and affected sides was confirmed by the tibial percussion test.<BR>[Conclusions] These findings indicated that the tibia percussion test in addition to confirmation of characteristic clinical conditions, such as the initial condition of the disease and the severity of tenderness, is useful for the evaluation of conditions of this disease.

MRI Diagnosis of Spontaneous Osteonecrosis of the Knee :A Report of 15 Cases / 实用放射学杂志

Objective To explore the clinical and MRI features of spontaneous osteonecrosis of the knee(SONK).Methods 15 patients with SONK diagnosed by clinic and imaging were collected.All of cases were examined by MRI,of them 5 cases underwent CT scan and 3 cases underwent radiographic examinations.Results The subchondral lesions were seen in all cases on MRI and the lesions located in the femoral condyle weight-bearing zone in 14 cases.The subchondral "fracture cleft"sign was found in 2 cases;the subchondral long T1 and short T2 linear abnormal signal intensity surrounding with bone marrow edema were shown by MRI in 3 cases of them.The subchondral focal lesions were slight long T1 and long T2 signal intensity in 10 cases.The subchondral lesion were showed clearly only in 2 cases of 5 cases with CT scan,and only 1 case of 3 cases with plain X-ray examinations.Conclusion MRI is more sensitive than CT and radiography in showing the lesions of SONK.The SONK can be diagnosed based on the clinical and MRI features.