Intra-articular anesthesia and knee muscle response

Background: Many receptors located within the intra-articular knee structures contribute to the neuromuscular responses of the knee. The purpose was to compare the automatic postural response induced by a perturbation at the foot before and after an intra-articular injection of a local anesthetic (bupivicaine), after a saline (sham) injection, and after no intra-articular injection (control) in the knee. Methods: Muscle onset latencies and automatic response magnitudes for the vastus medialis, vastus lateralis, biceps femoris, medial hamstrings, tibialis anterior, and gastrocnemius were measured using electromyography (EMG) when anteriorly directed perturbations were applied to the feet of 30 subjects. All subjects then received a lidocaine skin injection followed by: an intra-articular bupivicaine injection (treatment group); an intra-articular saline injection (sham group); or no injection (control group), depending on their randomized group assignment. The perturbation tests were then repeated. Findings: Muscle onset latencies and automatic response magnitudes did not change as a result of the intra-articular injections. Latencies were significantly greater for the vastus medialis and vastus lateralis when compared to the medial hamstrings, biceps femoris and tibialis anterior (P \u3c 0.001). Automatic response magnitudes for the tibialis anterior were significantly greater than those of the hamstrings, which were greater than those of the quadriceps (P \u3c 0.001). Interpretation: There were no differences in muscle response when anteriorly directed perturbations were applied to the foot with or without an injection of local anesthetic in the knee. Intra-articular receptors were either unaffected by the anesthetic or the extra-articular receptors or receptors of the other joints were able to compensate for their loss

Changes in muscle activation during wall slides and squat-machine exercise

Closed kinetic chain exercises are commonly used in strengthening and rehabilitation programs. Altering positions of body segments and supports might affect the way these exercises are performed. The purpose of this study was to compare gluteal, quadriceps, hamstring, and plantar flexor muscle activations during wall-slide (WS) vs. squat-machine (SM) exercise. In addition, the effects of support location and foot position were investigated. Twenty women performed 8 exercises, to 60°of knee flexion. Results indicated that placing the foot forward caused an increase in all muscle activations except in the plantar flexors, which showed an increase with the foot placed in line with the hip. This effect was exaggerated during WS for the plantar flexors and quadriceps and during SM for the hamstrings. When the support was located at the scapular level, hamstring and gluteal activations were greater, and quadriceps activity was less during SM than during WS. These results could be used to target specific muscle groups during strengthening exercise

The effect of high-lntensity trunk exercise on bone mineral density of postmenopausal women

The purpose of this study was to determine the effect of a 1-year trunk resistive exercise program on bone mineral density at the lumbar spine and hip in postmenopausal women. Forty-nine subjects were divided into exercise and control groups. Dual photon absorptiometry was used to measure bone mineral density and the Muscle Examination and Exercise Dosimeter 3000 system was used to assess trunk muscle strength. Resistive exercise target levels for the exercise group were based on the results of the trunk muscle strength tests. The exercise group performed 3 sets of 10 repetitions for each of the sit-up, prone trunk extension, and double leg flexion exercises. The subjects were seen once per month and performed the exercises a minimum of three times per week. The bone mineral density and strength tests were done at baseline, at 6 months and at 12 months. The results of the study showed that 1) the dual photon absorptiometry method and the Muscle Examination and Exercise Dosimeter 3000 system were highly reliable in measuring bone mineral density and trunk muscle strength, respectively; and 2) no significant differences were found between the exercise and control groups at lumbar vertebrae L2, L3, L4, L2-L4, and the femoral neck, Ward’s triangle, and trochanteric region of the proximal femur at baseline, 6-month, and 12-month evaluation sessions. © Lippincott-Raven Publishers

The effects of myofascial release with foam rolling on performance

In the last decade, self-myofascial release has become an increasingly common modality to supplement traditional methods of massage, so a masseuse is not necessary. However, there are limited clinical data demonstrating the efficacy or mechanism of this treatment on athletic performance. The purpose of this study was to determine whether the use of myofascial rollers before athletic tests can enhance performance. Twenty-six (13 men and 13 women) healthy college-aged individuals (21.56 ± 2.04 years, 23.97 ±3.98 body mass index, 20.57 ±12.21 percent body fat) were recruited. The study design was a randomized crossover design in which subject performed a series of planking exercises or foam rolling exercises and then performed a series of athletic performance tests (vertical jump height and power, isometric force, and agility). Fatigue, soreness, and exertion were also measured. A 2 × 2 (trial × gender) analysis of variance with repeated measures and appropriate post hoc was used to analyze the data. There were no significant differences between foam rolling and planking for all 4 of the athletic tests. However, there was a significant difference between genders on all the athletic tests (p ≤ 0.001). As expected, there were significant increases from pre to post exercise during both trials for fatigue, soreness, and exertion (p ≤ 0.01). Postexercise fatigue after foam rolling was significantly less than after the subjects performed planking (p ≤ 0.05). The reduced feeling of fatigue may allow participants to extend acute workout time and volume, which can lead to chronic performance enhancements. However, foam rolling had no effect on performance. © 2013 National Strength and Conditioning Association

Clinical practice guidelines linked to the international classification of functioning, disability and health from the orthopaedic section of the American physical therapy association

Pathoanatomical features/differential diagnosis Clinicians should perform assessments and identify clinical A findings in patients with neck pain to determine the potential for the presence of serious pathology (eg, infection, cancer, cardiac involvement, arterial insufficiency, upper cervical ligamentous insufficiency, unexplained cranial nerve dysfunction or fracture), and refer for consultation as indicated. IMAGING Clinicians should utilize existing guidelines and appropriate - A ness criteria in clinical decision making regarding referral or consultation for imaging studies for traumatic and nontraumatic neck pain in the acute and chronic stages. EXAMINATION - OUTCOME MEASURES Clinicians should use validated self-report questionnaires for A patients with neck pain, to identify a patient\u27s baseline status and to monitor changes relative to pain, function, disability, and psychosocial functioning. EXAMINATION - ACTIVITY LIMITATIONS AND PARTICIPATION MEASURES Clinicians should utilize easily reproducible activity limitation F and participation restriction measures associated with the patient\u27s neck pain to assess the changes in the patient\u27s level of function over the episode of care. EXAMINATION - PHYSICAL IMPAIRMENT MEASURES When evaluating a patient with neck pain over an episode of B care, clinicians should include assessments of impairments of body function that can establish baselines, monitor changes over time, and be helpful in clinical decision making to rule in or rule out (1) neck pain with mobility deficits, including cervical active range of motion (ROM), the cervical flexion-rotation test, and cervical and thoracic segmental mobility tests; (2) neck pain with headache, including cervical active ROM, the cervical flexion-rotation test, and upper cervical segmental mobility testing; (3) neck pain with radiating pain, including neurodynamic testing, Spurling\u27s test, the distraction test, and the Valsalva test; and (4) neck pain with movement coordination impairments, including cranial cervical flexion and neck flexor muscle endurance tests. Clinicians should include algometric assessment of pressure pain threshold for classifying pain. DIAGNOSIS/CLASSIFICATION Clinicians should use motion limitations in the cervical and C upper thoracic regions, presence of cervicogenic headache, history of trauma, and referred or radiating pain into an upper extremity as useful clinical findings for classifying a patient with neck pain into the following categories: • Neck pain with mobility deficits • Neck pain with movement coordination impairments (including whiplash-associated disorder [WAD]) • Neck pain with headaches (cervicogenic headache) • Neck pain with radiating pain (radicular) INTERVENTIONS: NECK PAIN WITH MOBILITY DEFICITS Acute For patients with acute neck pain with mobility deficits: Clinicians should provide thoracic manipulation, a program B of neck ROM exercises, and scapulothoracic and upper extremity strengthening to enhance program adherence. Clinicians may provide cervical manipulation and/or C mobilization. Subacute For patients with subacute neck pain with mobility deficits: Clinicians should provide neck and shoulder girdle endurance B exercises. Clinicians may provide thoracic manipulation and cervical C manipulation and/or mobilization. Chronic For patients with chronic neck pain with mobility deficits: Clinicians should provide a multimodal approach of the B following: • Thoracic manipulation and cervical manipulation or mobilization • Mixed exercise for cervical/scapulothoracic regions: neuromuscular exercise (eg, coordination, proprioception, and postural training), stretching, strengthening, endurance training, aerobic conditioning, and cognitive affective elements • Dry needling, laser, or intermittent mechanical/manual traction Clinicians may provide neck, shoulder girdle, and trunk en- C durance exercise approaches and patient education and counseling strategies that promote an active lifestyle and address cognitive and affective factors. INTERVENTIONS: NECK PAIN WITH MOVEMENT COORDINATION IMPAIRMENTS Acute For patients with acute neck pain with movement coordination impairments (including WAD): B Clinicians should provide the following: • Education of the patient to - Return to normal, nonprovocative preaccident activities as soon as possible - Minimize use of a cervical collar - Perform postural and mobility exercises to decrease pain and increase ROM • Reassurance to the patient that recovery is expected to occur within the first 2 to 3 months. Clinicians should provide a multimodal intervention ap- B proach including manual mobilization techniques plus exercise (eg, strengthening, endurance, flexibility, postural, coordination, aerobic, and functional exercises) for those patients expected to experience a moderate to slow recovery with persistent impairments. Clinicians may provide the following for patients whose C condition is perceived to be at low risk of progressing toward chronicity: • A single session consisting of early advice, exercise instruction, and education • A comprehensive exercise program (including strength and/or endurance with/without coordination exercises) • Transcutaneous electrical nerve stimulation (TENS) Clinicians should monitor recovery status in an attempt to F identify those patients experiencing delayed recovery who may need more intensive rehabilitation and an early pain education program. Chronic For patients with chronic neck pain with movement coordination impairments (including WAD): C Clinicians may provide the following: • Patient education and advice focusing on assurance, encouragement, prognosis, and pain management • Mobilization combined with an individualized, progressive submaximal exercise program including cervicothoracic strengthening, endurance, flexibility, and coordination, using principles of cognitive behavioral therapy • TENS INTERVENTIONS: NECK PAIN WITH HEADACHES Acute For patients with acute neck pain with headache: Clinicians should provide supervised instruction in active B mobility exercise. Clinicians may provide C1-2 self-sustained natural apophyseal C glide (self-SNAG) exercise. Subacute For patients with subacute neck pain with headache: Clinicians should provide cervical manipulation and B mobilization. C Clinicians may provide C1-2 self-SNAG exercise. Chronic For patients with chronic neck pain with headache: Clinicians should provide cervical or cervicothoracic manipu- B lation or mobilizations combined with shoulder girdle and neck stretching, strengthening, and endurance exercise. INTERVENTIONS: NECK PAIN WITH RADIATING PAIN Acute For patients with acute neck pain with radiating pain: Clinicians may provide mobilizing and stabilizing exercises, C laser, and short-term use of a cervical collar. Chronic For patients with chronic neck pain with radiating pain: Clinicians should provide mechanical intermittent cervical B traction, combined with other interventions such as stretching and strengthening exercise plus cervical and thoracic mobilization/manipulation. Clinicians should provide education and counseling to B encourage participation in occupational and exercise activities

Inhibition of Arp2/3-mediated actin polymerization by PICK1 regulates neuronal morphology and AMPA receptor endocytosis

The dynamic regulation of actin polymerisation plays crucial roles in cell morphology and endocytosis. The mechanistic details of these processes and the proteins involved are not fully understood, especially in neurons. PICK1 is a PDZ-BAR-domain protein involved in regulated AMPAR endocytosis in neurons. Here, we demonstrate that PICK1 binds F-actin and the actin-nucleating Arp2/3 complex, and potently inhibits Arp2/3-mediated actin polymerisation. RNAi knockdown of PICK1 in neurons induces a reorganisation of the actin cytoskeleton resulting in aberrant cell morphology. Wild-type PICK1 rescues this phenotype, but a mutant PICK1 (W413A) that does not bind or inhibit Arp2/3 has no effect. Furthermore, this mutant also blocks NMDA-induced AMPAR internalisation. This study identifies PICK1 as a new negative regulator of Arp2/3-mediated actin polymerisation that is critical for a specific form of vesicle trafficking and also for the development of neuronal architecture