Revision Anterior Cruciate Ligament Reconstruction: Analysis of the Causes of Failure, Associated Injuries and Clinical Results / 대한정형외과학회잡지

PURPOSE: The aim of this study was to analyze the causes of failure after a primary anterior cruciate ligament reconstruction (ACLR), associated injuries, and the clinical results of revision ACLR. MATERIALS AND METHODS: This study evaluated 46 patients (46 knees), who were followed at least two years after revision ACLR. The evaluations included the causes of failure after primary ACLR, associated injuries, 2000 International Knee Documentation Committee (IKDC) subjective knee scores, Lachman test, Pivot shift test, and KT-1000 arthrometer measurement. RESULTS: The most common cause of failure was trauma (27 patients, 58.7%) and 19 failures (19 patients, 41.3%) were caused using an inappropriate surgical technique. The associated injuries were meniscus tears in 29 cases (63.0%) and articular cartilage injuries of Outerbridge grade II to IV in 19 cases (41.3%). The IKDC scores, Lachman test, Pivot shift test, and KT-1000 arthrometer measurements were improved significantly at the final follow-up. CONCLUSION: The most common cause of failure after primary ACLR was trauma. One stage revision ACLR resulted in relatively satisfactory stability but less satisfactory clinical function than the primary reconstruction, as reported previously, which is believed to be due to the more associated injuries.

Bilateral Hypoplasia of the Medial and Lateral Menisci

Hypoplasia of the meniscus is a very rare congenital abnormality, with only a few cases reported to date. A 9-year-old girl visited our hospital due to lateral knee pain following a hyperextension injury to the left knee. Magnetic resonance imaging showed hypoplasia of the medial and lateral menisci, as well as a posterior horn tear of the lateral meniscus, in both knee joints. To our knowledge, this is the first report of a patient with hypoplasia of the medial and lateral menisci in both knee joints.

Patterns and Influencing Factors of Medial Meniscus Tears in Varus Knee Osteoarthritis

PURPOSE: To investigate the patterns of medial meniscus (MM) tears in patients with varus knee osteoarthritis who underwent total knee arthroplasty and analyze the factors that could affect MM tears. MATERIALS AND METHODS: The patients (365 knees, 268 patients) were classified into three groups; group I with MM posterior horn (PH) tear only; group II with MM root tear only; and group III with MMPH plus root tear. The following factors were evaluated: age, gender, body mass index, varus deviation of the mechanical axis, medial proximal tibial angle, posterior tibial slope (PTS), and anterior cruciate ligament (ACL) integrity (normal, degeneration, and tear or absence). RESULTS: MM tears were identified in all knees. The patterns of the combined MMPH tears in group III were less complex than those in group I. Varus deviation and PTS were significantly greater in group III than groups I and II. In group III, there were significantly more cases of ACL tear or absence than groups I and II. The others showed no differences among three groups. CONCLUSIONS: Severe varus knee osteoarthritis was always accompanied by MM tears. Risk factors for MMPH plus root tears were severe varus deformity, great PTS, and ACL tear or absence.

Relationship between Mucoid Degeneration of the Anterior Cruciate Ligament and Posterior Tibial Slope in Patients with Total Knee Arthroplasty

PURPOSE: The purpose was to analyze the relationship between posterior tibial slope (PTS) and mucoid degeneration of the anterior cruciate ligament (ACL) in patients with total knee arthroplasty. MATERIALS AND METHODS: Four hundred and twenty-four patients (24 males and 400 females; 636 knees) who received total knee arthroplasty for osteoarthritis were included. Their mean age was 68.9 years (range, 48 to 88 years). The patients were classified into three groups according to the status of ACL; normal ACL group (group I), mucoid degeneration of ACL group (group II) and ruptured or absent ACL group (group III). Plain lateral radiographs were used to measure the PTS and the values were compared among groups. RESULTS: There were no significant differences with regard to gender, age and left-to-right side ratio among groups (p>0.05). The mean PTS was 9.9degrees (range, 0.6degrees to 20.1degrees) in group I (161 knees), 10.8degrees (range, 0.2degrees to 21.8degrees) in group II (342 knees) and 12.3degrees (range, 2degrees to 22.2degrees) in group III (133 knees), which showed significant differences (p<0.001). CONCLUSIONS: The patients with mucoid degeneration of the ACL and those with ruptured or absent ACL had greater PTS than those with normal ACL. These findings suggest that an increased PTS may be one of the causative factors for mucoid degeneration of the ACL.

Total Knee Arthroplasty Using a Posterior Cruciate Ligament Sacrificing Medial Pivot Knee: Minimum 5-year Follow-up Results

PURPOSE: To evaluate minimum 5-year follow-up clinical and radiological results of total knee arthroplasty (TKA) using a posterior cruciate ligament sacrificing (PS), non-substituting Advance Medial Pivot Knee. MATERIALS AND METHODS: One hundred and twenty knees in 80 patients who could be followed up for more than 5 years after TKA using the PS Advance Medial Pivot Knee were evaluated retrospectively. The evaluations included the preoperative and postoperative range of motion (ROM), tibiofemoral angle, Knee Society (KS) knee and function scores, and Western Ontario and McMaster Universities Arthritis Index (WOMAC) score. The Kaplan-Meier method was used for survival analysis. RESULTS: The ROM increased from a preoperative mean flexion contracture of 7.6degrees and further flexion of 115.1degrees to a postoperative mean flexion contracture of 1.5degrees and further flexion of 120.5degrees. The tibiofemoral angle was changed from 4.6degrees varus preoperatively to 5.8degrees valgus postoperatively. The KS knee and function scores as well as WOMAC score significantly improved after surgery (p<0.05). Complications developed in 4 cases (3.3%): 2 cases of periprosthetic patellar fracture (1.7%) and 2 cases of aseptic loosening (1.7%). The seven-year survival rate was 98.1% in the Kaplan-Meier survival analysis. CONCLUSIONS: The minimum 5-year follow-up results of TKA using the PS Medial Pivot Knee were satisfactory.