Kook Hyun Wang

Unfavorable Results of Partial Meniscectomy for Complete Posterior Medial Meniscus Root Tear With Early Osteoarthritis: A 5- to 8-Year Follow-Up Study

PURPOSE The aim of this retrospective study was to evaluate the clinical and radiographic outcomes of arthroscopic partial meniscectomy for complete posterior medial meniscus root tear (PMMRT) in patients with early radiographic evidence of knee osteoarthritis at a minimum follow-up of 5 years. METHODS Forty-six cases had complete PMMRT with follow-up of at least 5 years and were treated with arthroscopic partial meniscectomy. On the basis of medical records, we reviewed the arthroscopic findings of joint degeneration (Outerbridge grading), clinical results using the modified Lysholm (ML) knee score and a patient questionnaire, and radiographic evaluation of degeneration using Kellgren-Lawrence (KL) grading. RESULTS The incidence of complete PMMRT in the study population was 15%. At a mean follow-up of 78 months (range, 60 to 103 months), the mean ML score significantly improved from 72 (range, 62 to 78) preoperatively to 77 (range, 70 to 98) at final follow-up (P < .01), 16 patients (35%) showed progression of degeneration from KL grade 0 to 2 preoperatively to KL grade 2 to 4, 56% of patients indicated improvement in pain, 67% of patients were satisfied with the results of the procedure, and 19% of patients underwent reoperation. There was a significant negative correlation between chondral wear during arthroscopy (ρ = -0.516, P = .002) and preoperative KL grade (ρ = -0.429, P = .004) with ML score at final follow-up. CONCLUSIONS Although arthroscopic partial meniscectomy for complete PMMRT significantly improved ML scores postoperatively, only 56% of patients had improvement in pain, 67% were satisfied with the outcome of the procedure, and 35% showed radiographic progression of osteoarthritis at a mean follow-up of 77 months. LEVEL OF EVIDENCE Level IV, therapeutic study.

Arthroscopic Direct Repair for a Complete Radial Tear of the Posterior Root of the Medial Meniscus

We report here on a new arthroscopic direct repair technique for a radial tear of the posterior root of the medial meniscus (PRMM) using a posterior trans-septal portal. Radial tears of the PRMM are commonly observed in the elderly population of Korea and Japan, and the life style of these people requires squatting and kneeling down in daily life. A radial tear of the PRMM results in the loss of hoop tension and this accelerates degenerative changes in the knee joint and causes early osteoarthritis. Several reports in the medical literature have focused on various repair techniques for these tears by using pull out sutures. These techniques result in nonanatomic fixation of the meniscus, which may lead to disturbed meniscal excursion and failure to restore hoop tension. Arthroscopic direct repair may contribute to restoring hoop tension and preventing accelerated degenerative changes in the knee joint of these patients.

Osteonecrosis of the lateral femoral condyle following anterior cruciate ligament reconstruction: is bone bruising a risk factor?

Osteonecrosis of the knee is extremely rare following anterior cruciate ligament (ACL) reconstruction surgery. We report a case of osteonecrosis of the lateral femoral condyle in a patient after ACL reconstruction. The osteonecrotic lesion occurred in the same area as a large bone bruise, which was sustained at the time of the initial injury. We hypothesize that the combination of bone bruising and femoral tunnel drilling for ACL reconstruction may have compromised the overall vascularity of the articular cartilage and the subchondral bone, thereby resulting in osteonecrosis.

Posterior Reattachment of a Radial Tear in the Posterior Root of the Medial Meniscus

The new posterior vertical mattress suture technique is technically easier to perform and provides more secure fixation than the arthroscopic simple or horizontal stitch techniques and may contribute to restoring function of the medial meniscus.

Freiberg's disease: quantitative assessment of osteonecrosis on three-dimensional CT.

BACKGROUND The extent of necrosis is the main determining factor in the outcome of osteonecrosis. There is no method for measuring the extent of osteonecrosis of the metatarsal head in Freibergs disease. The purpose of this study was to determine the reliability and prognostic ability of a new method for measurement of the extent of osteonecrosis in Freibergs disease on three-dimensional computed tomography. METHODS A retrospective review of 11 cases with symptomatic Freibergs disease in ten patients (5 males and 5 females; mean age, 27 years) undergoing computed tomography between July 2005 and September 2007 was performed. Two investigators (K.A.C. and H.K.O.) used a new method to measure the necrotic extent of the metatarsal head: the necrotic angle ratio of necrotic arc angle to normal arc angle of the articular surface on the sagittal reconstruction image of computed tomography. The interobserver reliability was determined for computed tomography measurement. Correlation between the Smillie staging using radiographs and the necrotic angle ratio on computed tomography was also evaluated. RESULTS One patient presented with stage I disease (Smillie staging), one with stage II, two with stage III, five with stage IV, and two with stage V, respectively. The necrotic angle ratio of the metatarsal head was 14% in stage I, 21% in stage II, 34% in stage III, 43% in stage IV, and 53% in stage V. The interobserver reliability for computed tomography measurement was high (Cronbach α=0.96). We found the increase of the necrotic extent in proportion to the Smillie stage. The Smillie staging using radiographs and the necrotic angle ratio on computed tomography were significantly correlated. (P<0.05) CONCLUSIONS Three-dimensional computed tomography measurement of the necrotic extent of the metatarsal head is a reliable and useful method in evaluating the staging of Freibergs disease and may eventually help to optimize treatment.

Isolated osteochondral fracture of the patella without patellar dislocation.

Chondral fractures of the patella are associated with acute dislocation of the patella. Osteochondral fracture in patellar dislocation is located in the medial facet of the patella. This article presents a case of a 15-year-old female ballerina with isolated displaced osteochondral fracture of the patella without patellar dislocation. She had no history of trauma. A Merchants view of both knees showed mild subluxation of the patella, a small fragment on the lateral aspect of the knee, and a small defect of the centromedial patella. Axial magnetic resonance imaging (MRI) revealed an osteochondral fragment measuring 13 mm medial to the patella. However, the medial patellofemoral ligament and medial retinaculum were intact. An effusion on the medial side of the patella consistent with hemarthrosis was observed. An absence of a contusion or bone bruise on the lateral femoral condyle was shown. The loose body was removed arthroscopically. Intraoperative findings included a 1.5×2 cm osteochondral fragment. It is unusual that the osteochondral patellar defect site in this patient was in the inferior and central areas of the patella. Patellar chondral fractures without dislocation or patella fracture are rare. Therefore, the possibility of a trivial trauma leading to an osteochondral fracture should be kept in mind in adolescent and young adults who present with knee pain and hemarthrosis.

Arthroscopic Transpatellar Cannulated Screw Fixation of Tibia Eminence Fractures in the Adult

Arthroscopic transpatellar screw fixation with a cannulated screw and washer is a simple, effective, and safe technique providing stable fracture fixation to allow immediate mobilization with minimal loss of extension in type II and III tibial eminence fractures in adults.

Central Popliteal Mass Due to Communicating Posterior Cruciate Ligament Cyst: An Indication for a Combined Approach

An isolated symptomatic posterior cruciate ligament cyst is uncommon, and extra-articular communication of this cyst is extremely rare. We report a case of a symptomatic communicating posterior cruciate ligament cyst presenting as a central popliteal mass. In view of the large extra-articular extension of this cyst and its close proximity to the popliteal neurovascular structures, we successfully treated this cyst with a combined arthroscopic and open approach.