Novel press-fit technique of patellar bone plug in anterior cruciate ligament reconstruction is comparable to interference screw fixation.

PURPOSE: Conventional press-fit technique for anterior cruciate ligament reconstruction (ACLR) is performed with extraction drilling of the femoral bone tunnel and manual shaping of the patellar bone plug. However, the disadvantages of this technique include variation in bone plug size and, thus, the strength of the press-fit fixation, bone loss with debris distribution within the knee joint, potential heat necrosis, and metal wear debris due to abrasion of the guide wire. To overcome these disadvantages, a novel technique involving punching of the femoral bone tunnel and standardized compression of the bone plug was introduced. In this study, the fixation strength and apparent stiffness were tested and compared to that of the gold-standard interference screw fixation technique in three flexion angle configurations (0°/45°/90°) in a porcine model. We hypothesized that the newly developed standardized press fit fixation would not be inferior to the gold standard method. METHODS: Sixty skeletally mature porcine knees (30 pairs) were used. Full-thickness central third patellar tendon strips were harvested, including a patellar bone cylinder of 9.5 mm in diameter. The specimens were randomly assigned to 10 pairs per loading angle (0°, 45°, 90°). One side of each pair was prepared with the press-fit technique, and the contra-lateral side was prepared with interference screw fixation. Equivalent numbers of left- and right-sided samples were used for both fixation systems. A three-way multifactor ANOVA was carried out to check for the influence of (a) fixation type, (b) flexion angle, and (c) side of the bone pair. RESULTS: The primary fixation strength of femoral press-fit graft fixation with punched tunnels and standardized bone plug compression did not differ significantly from that of interference screw fixation (p = 0.51), which had mean loads to failure of 422.4 ± 134.6 N and 445.4 ± 135.8 N, respectively. The flexion angle had a significant influence on the maximal load to failure (p = 0.01). Load values were highest in 45° flexion for both fixations. The anatomical side R/L was not a statistically significant factor (p = 0.79). CONCLUSION: The primary fixation strength of femoral press-fit graft fixation with punched femoral tunnels and standardized bone plug compression is equivalent to that of interference screw fixation in a porcine model. Therefore, the procedure represents an effective method for ACL reconstruction with patellar or quadriceps tendon autografts including a patellar bone plug.

[Osteochondral injury of the femoral insertion of the deep medial collateral ligament of the knee-is there a successful surgical treatment?] / Osteochondrale Verletzung des femoralen Ansatzes des tiefen medialen Seitenbandes am Knie ­ chirurgisch erfolgsversprechende Therapie?!

Isolated ruptures of the deep portion of the medial collateral ligament (MCL) without clinical instability can mostly be treated conservatively with good clinical results. A 10-year-old girl was initially also treated conservatively. As symptoms of pain and limited range of motion were not resolved after 3 months of conservative treatment and although there were no signs of instability, it was decided to proceed with the surgical intervention. A small osteochondral fragment on the femoral insertion of the deep MCL (medial meniscofemoral ligament) was removed and the soft tissue portion of the ligament was reinserted in the anatomical footprint. The patient showed complete resolution of the pain and a full range of motion of the knee joint. At the last follow-up 18 months after surgery the patient was completely free of symptoms.

Surgical hip dislocation is more powerful than arthroscopy for achieving high degrees of acetabular correction in pincer type impingement.

BACKGROUND: With the development of hip arthroscopy (HA), a shift away from surgical hip dislocation (SHD) is becoming a noticeable reality. It was the aim of this study to examine whether SHD provides a benefit over HA regarding its corrective power in the treatment of femoroacetabular impingement (FAI). HYPOTHESIS: It was hypothesized that SHD provides the more powerful tool for acetabular correction in FAI surgery compared to HA. METHOD: The examined cohort consisted of 85 hips of which 31 (36%) underwent a high degree of acetabular correction which was defined as a correction of >2 standard deviations from the population mean. A lateral center edge angle (LCE) correction>12° or an acetabular index (AI) correction>8° were therefore considered to high correction. A logistic regression model was applied to determine factors influencing high correction in FAI surgery. Subsequent adjustment was performed using a multivariate model. RESULTS: After adjusting for pre-operative acetabular orientation, SHD showed a pronounced influence on the likelihood of achieving the adequate degree of high acetabular correction (odds ratio (OR) 10.0 confidence interval (C.I) 2.3 to 44.0, p=0.002). On the other hand, SHD showed no influence on femoral correction (p=n.s). CONCLUSION: Surgical hip dislocation is a powerful modality for achieving high degrees of acetabular correction in the situation of a femoroactabular conflict, being defined as an LCE correction of>12° or AI correction of>8°. The reason for these results may be seen in the excellent exposure and the improved possibility of performing dynamic intra-operative examination to verify the results. The benefits are only limited to large acetabular correction. These findings should provide a helpful tool for decision making in clinical practise. LEVEL OF EVIDENCE: Level III retrospective cohort study.