The Impact of the Anteromedial Impingement Fracture of Tibial Plateau in Posterolateral Corner Injuries / 中国运动医学杂志

Objective To identify the incidence of the anteromedial impingement fracture of tibial plateau in the posterolateral corner injuries,and to confirm the relationship between the extent of the anteromedial tibial impingement fracture and the severity of the posterolateral instability of the knee joint.Methods The radiographic images of the posterolateral corner injuries were reviewed retrospectively to identify the incidence of the anteromedial impingement fracture of the tibial plateau.A matched group of the posterolateral corner injury patients without the anteromedial impingement fracture was compared with the anteromedial impingement fracture group for the posterior instability and varus instability.And the anteromedial impingement fracture group was subdivided into a marginal fracture group and a compression fracture group based on the size of the fracture,and the posterior instability and medial instability were compared between the two groups.Results From January 2007 to January 2017,there were 266 patients with posterolateral corner injuries admitted,with 19 (7.1％) combined with the anteromedial impingement fractures of the tibial plateau.The posterior instability was significantly severer in the fracture group than the control group (P=0.030),while there were no significant differences in the varus instability between them (P=0.800).Similarly,the posterior instability was significantly severer in the marginal group compared to the compression group (P=0.026),but without significant differences in the varus instability (P=0.397).However,the compression fracture group had a higher risk to have neurovascular injuries (of the popliteal artery and the common peroneal nerve) compared with the marginal fracture group.Conclusion The incidence of the anteromedial impingement fracture of the tibial plateau in posterolateral corner injuries was 7.1％.The anteromedial impingement fracture of the tibial plateau may indicate more severe posterior instability,and a compression fracture may suggest more severe posterior instability compared with the marginal fracture.If there is a compression type fracture,the neurovascular status must be carefully evaluated in addition to the examination of the posterolateral and posterior instability.

Short-Term Results of Total Knee Arthroplasty with Anterior-Posterior Glide LCS Mobile-Bearing System

PURPOSE: To evaluate the clinical and radiological results of total knee arthroplasty (TKA) using the anterior-posterior glide (APG) low contact stress (LCS) mobile-bearing system. MATERIALS AND METHODS: We evaluated 130 knees in 117 patients who had undergone TKA with APG LCS mobile-bearing system between September 2005 and July 2007 and could be followed over 5 years. The mean follow-up period was 68 months. The clinical and radiological results were evaluated using the American Knee Society Scoring System, Oxford knee score and the American Knee Society Roentgenographic Evaluation and Scoring System. And we analyzed short-term postoperative complications. RESULTS: The average range of motion of the knee joint was 107.9degrees (range, 70degrees to 135degrees) preoperatively and 125.2degrees (range, 90degrees to 135degrees) at the last follow-up. The average knee and functional scores were improved from 39.1 and 42.0 to 71.2 and 75.6, respectively, between the preoperative and last follow-up evaluation. The Oxford knee score was decreased from 42.9 preoperatively to 23.1 at the last follow-up. The femoro-tibial angle (anatomical axis) changed from 10.1degrees varus preoperatively to 3.3degrees valgus at the last follow-up. Radiolucency was observed in 14% of all cases. There were 1 case of traumatic dislocation of the polyethylene liner, 1 case of aseptic loosening and 6 cases of posterior instability because of posterior cruciate ligament (PCL) insufficiency. CONCLUSIONS: TKA with APG LCS mobile-bearing system demonstrated relatively good short-term clinical and radiological results. However, further considerations for posterior instability associated with PCL insufficiency are needed.

Posterior Instability after Posterior Cruciate Ligament Substituted TKA: Case Report / 대한정형외과학회잡지

Posterior instability after a posterior ligament substituted total knee replacement is considered impossible due to the cam and post mechanism. Therefore, it has not been considered easily as a problem necessitating revision surgery. We report two cases of posterior instability after a fixed bearing posterior cruciate ligament substituted total knee replacement with a review of relevant literature.

Dislocation of Tibial Insert after Fixed Bearing TKA using Minimal Invasive Surgery: A Case Report

Posterior instability after mobile bearing total knee replacement may be caused by gap imbalance, component malpo- sition, and delayed rupture of posterior cruciate ligament, but could not be easily considered other cause except component breakage in fixed bearing posterior cruciate substituted total knee replacement. The dislocation of tibial polyethylene insert was reported after mobile bearing total knee replacement but rare after fixed bearing total knee replacement. We report a case of dislocation of tibial polyethylene insert that have been found at a patient who had continuing posterior instability after fixed bearing posterior cruciate ligament substituted total knee replacement with a review of article.

Posterior Instability in Shoulder / 대한정형외과학회잡지

Posterior instability of the shoulder is far less common than anterior or multidirectional instability. There is still controversy in the diagnosis and treatment of recurrent posterior instability, and many treatment protocols have been advocated. However the failure rate as high as 50% was reported. The purpose of this study is to introduce characteristic physical findings of posterior instability, to present our operative techniques, and to report the efficacy of a superior shift of the postero-inferior capsule in the treatment of recurrent posterior instability. From June 1995 to September 1996, five patients, six shoulders underwent postero-inferior capsular shift for posterior instahility and were evaluated at an average of 17 months(ranged from 9 to 26 months) after operation. The average age was 22.4 years. Preoperatively, mean scores of pain, stability and function according to American Shoulder and Elbow Society (ASES) scoring system were 21, 9, and 16 points respectively and mean overall ASES score was 46 points. After surgery, the average range of motion was 175 of forward elevation and 74 of external rotation and internai rotation in back was up to the sixth thoracic level. Postoperative mean scores of pain, stability and function were 29, 34 and 25 points respectively and mean overall ASES score was 88.5 points. No patient had a recurrence of posterior instability. All patients had satisfactory results with significant improvement in stability and function except one case who had multidirectional instability that mainly involved the posterior component

The complications of the Graf stabilization for lumbar disc herniation with posterior instability / 영남의대학술지

The Graf stabilization has been introduced in treating lumbar spinal disorder associated with posterior instability. This study reviewed some problems of the Graf instrumentation as a soft stabilizer. The purpose of this study is to analyse the problems of the soft stabilization in spinal instability. We reviewed 145 cases which were operative treatment using the Graf instrument for lumbar spinal disorder associated with posterior instability at our department from May, 1991 to Dec, 1995. The mean follow up periods was 29 months ranging from 24 months to 6 years 8 months. Of the 145 cases, 22 cases were showed the problem. The diagnostic method were simple x-ray, flexion-extension lateral stress view and CT scan. Results were as follows : Adjacent segmental instability was 10 cases(6.9%), disc space narrowing was 8 cases(5.5%), screw loosening was 3 cases(2.1%) and breakage of the Graf band was 1 case(0.6%). The problems of the soft stabilization were adjacent segmental instability, disc space narrowing, screw loosening, and breakage of the Graf band. But the rate of adjacent segmental instability and disc space narrowing was lower than other lumbar spinal instrumentation.