The Influence of L-menthol on Time Trial Running Performance in Recreational Runners

Purpose: This study investigated the effects of combined mouth rinse and topical application of L-menthol on perceptual responses and running performance under thermoneutral conditions (22 ± 2°C and 30-60% relative humidity). Methods: Twelve recreational male runners (age: 31.7 ± 3.8 years; age range: 27-39 years) completed a familiarization, a control test (CON) and two maximal 10-km time trials (counterbalanced randomized crossover design) performed in different days with a non-thermal cooling intervention (combined application of a L-menthol mouth rinse and topical L-menthol gel - MEN) or placebo (PLA). Performance and perceptual measures (thermal sensation, thermal comfort, ratings of perceived exertion and affective response) were recorded for every km completed in the 10-km test. Results: Performance time was lower in MEN (P = 0.03) and PLA (P = 0.003) compared to CON, but no differences were found between MEN vs PLA (P = 1.00). All perceptual responses increased over time in all conditions (P < 0.0001), but only the thermal sensation was lower (P = 0.01) in the MEN compared to CON. Conclusion: L-menthol strategies promote fresh sensations and may improve running performance in 10-km time trial in recreational runners, but the performance improvement could mainly be due to a placebo effect.

Correlation of static knee angle in kinematic and radiographic in medial knee osteoarthritis

Introduction The hip-knee-ankle (HKA) angle measured on a full-length weight bearing X-ray made in standing position is considered the gold standard to measure the knee static alignment. However, this method requires special equipment, involves significant radiation exposure and generates extra costs. The 3D motion capture can assess knee angles in a reliable and accurate way.

Objectives This study aimed to analyse the correlation between the HKA angle achieved in full-length X-ray and the in static knee kinematic analysis in patients with medial knee osteoarthritis (OA).

Methodology A descriptive study was design. Anterior-posterior full-limb radiographs were obtained using standard procedures in the same hospital. The HKA angle was measure by an experimental orthopaedic doctor. The kinematics were obtained using Visual3D software after 3D motion capture in two static positions: static comfortable position (Static-1) and a static standard position (Static-2). Kinematic data were filtered (6 Hz) and expressed in degrees (°). The knee joint was created by the distance between the distal end of the thigh and the proximal end of the shank. The angles lower than 180° were considered as varus alignment and those higher than 180° valgus alignment.

Results This study includes 36 patients (22 females; mean age 61,6 ± 8,4; weight 75,8 ± 12,7 kg, and height 161 ± 9,2 cm) with diagnosed medial knee OA Kellgren/Lawrence grade 2 (16 patients) or 3. The patients presented a mean of HKA of 176,2° ± 3,2 in X-ray; 182,1° ± 6,0 in Static-1 and 180,0° ± 5,6 in Static-2. A significant correlation was found between HKA angle and Static-1 (r = 0,525; p = 0,001) and between HKA angle and Static-2 (r = 0,556; p = 0,000).

Conclusion A moderate but significant correlation was found between X-ray and two measure of 3D motion capture in frontal knee angle. Clinically, 3D analysis may help health care professionals in a more practical way to identify the joint angles.

Sex Differences in Physiological Stress Induced by a Long-Lasting Adventure Race: A Prospective Observational Analytical Study

BACKGROUND

 In order to provide additional information on the behaviour of biochemical parameters related to stress responses to a specific long-term competition, we aimed to compare the stressful effects of a long-lasting competition on physiological variables in men and women.

METHODS

 This is a prospective observational analytical study. Twenty-five professional athletes, 15 men and 10 women, travelled 460 km for 4 days in an international edition of the Ecomotion/Pro AR World.

RESULTS

 After the competition, we detected an increase in α-amylase and cortisol levels and a decrease in salivary immunoglobulin A (lgA) levels. The relative percentage changes in α-amylase, IgA and cortisol levels were significantly higher in women than in men, whereas women had lower relative percentage changes in glucose and lactate levels compared with men. There was a decrease in lymphocyte, eosinophil and monocyte counts, with relative percentage decreases in lymphocytes and monocytes being significantly higher in female athletes than in males. There were increases in the serum activities of total creatine kinase (CK), the creatine kinase myocardial isoform (CKMB), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) at the end of the test, with significantly higher elevations of total CK, CKMB and LDH in men and ALT in women.

CONCLUSION

 Long-lasting competition induced stress, muscle damage, anaemia and changes in the immune system. Women had more intense responses of cortisol and leukocytes.

The posterior condylar offset ratio and femoral anatomy in anterior versus posterior referencing total knee arthroplasty

BACKGROUND

The preservation of joint anatomy is one of the key issues in total knee arthroplasty. The effect of the prosthesis' referencing system, relative to femoral anatomy, remains unknown. It was sought to determine if femoral anatomy, following total knee arthroplasty is better maintained using either anterior referencing or posterior referencing prosthesis. The posterior condylar offset ratio (PCOR) was employed for preoperative and postoperative radiographic comparison of femoral condyles. It was hypothesized that posterior referencing prosthesis would better restore condylar morphology.

METHODS

Sixty-six patients undergoing a total knee arthroplasty with anterior referenced Zimmer(®) NexGen(®) LPS prosthesis and ninety-one with posterior referenced Tornier(®) HLS Noetos(®) were divided into two groups according to the prosthetic model used and retrospectively compared. PCOR was calculated as the quotient of the distance between the posterior condylar border and the tangent to the posterior cortex of the femoral diaphysis, and the distance between the posterior condylar border and the tangent to the anterior cortex of the femoral diaphysis. PCOR was determined preoperatively and postoperatively and compared within each group and between both groups.

RESULTS

An increase in the PCOR (P<0.0001) following surgery was observed in both anterior referencing and posterior referencing models. No difference was noted when the postoperative PCOR was compared between both groups (P=0.61).

CONCLUSION

Both anterior and posterior referencing prosthesis lead to a similar increase of the PCOR following total knee arthroplasty.

LEVEL OF EVIDENCE

Level IV.

Artroplastia total trapézio-metacarpiana. Resultado a curto prazo de 2 implantes diferentes

Arizartrose é uma patologia muito comum que afecta frequentemente mulheres de meia-idade e por norma bilateralmente.

Muitas técnicas cirúrgicas têm vindo a ser descritas para o tratamento da rizartrose em estádios avançados, como é o caso da artrodese, da trapezectomia com ou sem interposição de tendão e/ou reconstrução ligamentar, dos implantes de silicone e das próteses totais trapézio-metacarpianas.

Os autores pretendem com este estudo comparar 2 tipos diferentes de implantes analisando retrospectivamente a utilização destes no tratamento de 15 doentes com rizartrose bilateral.

Na série estudada, a prótese trapézio-metacarpiana provou ser eficaz no alívio sintomático e no aumento da mobilidade e da força do polegar. O implante do tipo «ball-and-socket» obteve melhores resultados funcionais e um menor tempo de recuperação, em relação à prótese «anatómica».