No correlation between rotation of femoral components in the transverse plane and clinical outcome after total knee arthroplasty.

PURPOSE: It was hypothesized that malrotation of femoral component in total knee arthroplasty (TKA) will significantly impact clinical outcome. METHODS: Eighty-eight consecutive patients with primary osteoarthritis of the knee were prospectively evaluated. They received a cemented posterior stabilized TKA (NexGen, Zimmer/Biomet® Inc., Warsaw, IN, USA). The femoral component was placed in 3° of external rotation referenced to the posterior condylar line. Postoperatively, a CT scan was performed to evaluate rotation of femoral component in the transverse plane. SF-36, KSS, and WOMAC, as well as their range of motion was assessed prior to surgery, after 6 and 24 months. Data are presented as mean and standard deviation (SD), as well as range if applicable. Correlation analysis was performed between the placement of the femoral component in the transverse plane and the clinical outcome. RESULTS: Femoral component placement was on average 0.1° [SD 2.5°, range - 6.5° to + 6.5°] referenced to the surgical transepicondylar line showing a wide range between the two landmarks after surgery. After 6 months, WOMAC category 'physical function' correlated significantly with femoral component rotation (r = - 0.28, p = 0.007). After 24 months, WOMAC categories 'physical function' and 'pain' correlated significantly with femoral rotation (r = - 0.41, p < 0.001; and r = - 0.33, p = 0.001). No significant correlations were found between femoral component rotation and range of motion (r = 0.04), WOMAC category "stiffness", KSS, as well as SF-36 questionnaires. These reported formally significant correlations were without any clinical relevance. DISCUSSION: The study showed that there is a significant patients specific femoral component placement in the transverse plane. Internal or external malrotation of the femoral component does not correlate automatically with poor knee function. The lack of correlation between femoral component position and clinical as well as functional outcome underlines complexity and significant individuality of each patient. The surgeon should be aware of the finding and attention should be paid during surgery when significant divergency is seen between the two landmarks. Soft tissue balancing might be very crucial in these specific patients, which needs to be studied in depth in the future. LEVEL OF EVIDENCE: II.

Restoring tibiofemoral alignment during ACL reconstruction results in better knee biomechanics.

PURPOSE: Anterior cruciate ligament (ACL) reconstruction (ACLR) aims to restore normal knee joint function, stability and biomechanics and in the long term avoid joint degeneration. The purpose of this study is to present the anatomic single bundle (SB) ACLR that emphasizes intraoperative correction of tibiofemoral subluxation that occurs after ACL injury. It was hypothesized that this technique leads to optimal outcomes and better restoration of pathological tibiofemoral joint movement that results from ACL deficiency (ACLD). METHODS: Thirteen men with unilateral ACLD were prospectively evaluated before and at a mean follow-up of 14.9 (SD = 1.8) months after anatomic SB ACLR with bone patellar tendon bone autograft. The anatomic ACLR replicated the native ACL attachment site anatomy and graft orientation. Emphasis was placed on intraoperative correction of tibiofemoral subluxation by reducing anterior tibial translation (ATT) and internal tibial rotation. Function was measured with IKDC, Lysholm and the Tegner activity scale, ATT was measured with the KT-1000 arthrometer and tibial rotation (TR) kinematics were measured with 3Dmotion analysis during a high-demand pivoting task. RESULTS: The results showed significantly higher TR of the ACL-deficient knee when compared to the intact knee prior to surgery (12.2° ± 3.7° and 10.7° ± 2.6° respectively, P = 0.014). Postoperatively, the ACLR knee showed significantly lower TR as compared to the ACL-deficient knee (9.6°±3.1°, P = 0.001) but no difference as compared to the control knee (n.s.). All functional scores were significantly improved and ATT was restored within normal values (P < 0.001). CONCLUSIONS: Intraoperative correction of tibiofemoral subluxation that results after ACL injury is an important step during anatomic SB ACLR. The intraoperative correction of tibiofemoral subluxation along with the replication of native ACL anatomy results in restoration of rotational kinematics of ACLD patients to normal levels that are comparable to the control knee. These results indicate that the reestablishment of tibiofemoral alignment during ACLR may be an important step that facilitates normal knee kinematics postoperatively. LEVEL OF EVIDENCE: Level II, prospective cohort study.

The impact of different barrel sanitation approaches on the spoilage microflora and phenols composition of wine.

Careful control of spoilage microflora inside wine containers is a key issue during winemaking. To date, attention has been paid to the development of an effective protocol for the eradication of spoilage agents, especially Brettanomyces, from barrels. Few studies have taken into account the modifications caused by sanitation treatments in wine and wood barrels. In the present study the effects of two sanitation treatments (ozone and sodium hydroxide) on barrel spoilage microflora and the composition of the wine stored inside them were evaluated. The phenols of wine (38 compounds) were characterised using a UHPLC-MS during the first 3 months of wine ageing, to see possible alterations in composition due to the chemical exchange from wood to wine in presence of sanitising agents. With the same scope, a panel of 13 judges carried out sensorial analysis of wines. The results showed that the tested treatments had little effect on the organoleptic characteristics of wines, but underline the different performance of the sanitation treatments in terms of eradicating microorganisms.

Peroneal electromechanical delay and fatigue in patients with chronic ankle instability.

PURPOSE: The purpose of this study was to investigate the effect of chronic ankle instability (CAI) on electromechanical delay times (EMD) before and after fatigue. Understanding the mechanisms that contribute to CAI is essential for the development of effective rehabilitation programmes. It was hypothesized that patients with CAI will demonstrate prolonged EMD times compared to healthy subjects and that fatigue will cause greater increases in EMD times in the CAI group. METHODS: Twenty-one male volunteers participated in the study providing data on 16 ankles with CAI and 26 with no history of ankle injury. EMD was measured on an isokinetic dynamometer. Measurements were taken with the ankle in neutral (0°) and at 30° of inversion. All subjects followed an isokinetic fatigue protocol until eversion torque fell below 50 % of initial torque for three consecutive repetitions. A 2 × 2 × 2 ANOVA was used to calculate the effect of ankle status (CAI vs. healthy), fatigue, angle (0° vs. 30°) and their interactions on EMD. RESULTS: Fatigue caused a significant increase on EMD [non-fatigued: 122(29)ms vs. fatigue 155(54)ms; p < 0.001]. EMD times were shorter at 30° of inversion compared to neutral [neutral: 145(39)ms vs. 30° of inversion: 132(40)ms, p = 0.015]. An interaction effect for ankle status and angle was found (p = 0.026) with CAI ankles demonstrating longer EMD [CAI: 156(45)ms vs. healthy: 133(40)ms] in neutral but not at 30° of inversion [CAI: 133(46)ms vs. 132(33)ms]. CONCLUSIONS: Patients with CAI had longer EMD times in neutral, but not when the ankle was placed in inversion. This suggests that rehabilitation programmes may be more effective when retraining occurs with the ankle in neutral position. It is likely that low EMD times prevent ankle acceleration at the beginning of the mechanism of injury, but they are less important when the ankle has already inverted at 30°. Both CAI and healthy subjects demonstrated longer EMD after fatigue, emphasizing the importance of proper conditioning in the prevention of delayed peroneal response and subsequent ankle injury. Improving resistance to fatigue of the peroneals may prove to be an effective prevention tool of ankle sprain recurrence in patients with CAI. LEVEL OF EVIDENCE: III.

Comparison of knee flexion isokinetic deficits between seated and prone positions after ACL reconstruction with hamstrings graft: Implications for rehabilitation and return to sports decisions.

OBJECTIVES: Hamstrings grafts are commonly used in ACL reconstruction, however, the effect of graft harvesting on knee flexion strength has not been longitudinally evaluated in functional positions. We hypothesized that greater deficits in knee flexion strength exist in the prone compared to the seated position and these deficits remain as rehabilitation progresses. DESIGN: Case series. METHODS: Forty-two consecutive patients who underwent ACL reconstruction with a hamstrings graft were followed prospectively for 9 months. Isokinetic knee flexion strength at a slow and a fast speed were collected at 3, 4, 6, and 9 months in two different positions: conventional (seated) and functional (0° of hip flexion). RESULTS: Peak torque knee flexion deficits were higher in the prone position compared to the seated position by an average of 6.5% at 60°/s and 9.1% at 180°/s (p<0.001). CONCLUSIONS: Measuring knee flexion strength in prone demonstrates higher deficits than in the conventional seated position. Most athletes would not be cleared to return to sports even at 9 months after surgery with this method.