Connection between medial dorsal cutaneous nerve and saphenous nerve: case report.

PURPOSE: There are no data on the connection of the saphenous nerve (SN), located on the medial side of the foot, with the terminal branches of the superficial fibular nerve. The aim of this study is to reveal the variation that surgeons should pay attention to for anesthesia applied in foot surgeries. METHODS: In this study, the left foot of a 70-year-old female cadaver fixed with formalin was dissected. The distance to the medial malleolus and the incision line was recorded using digital caliper to determine the reference points in the resulting variation. RESULTS: It was observed that a branch from the SN, which arose from the SN and proceeded anteriorly to the upper part of the medial malleolus and continued towards the dorsum of the foot, hooked with a branch from the medial dorsal cutaneous nerve (MDCN). The branches arising from this hook were distributed on the medial edge of the foot up to the proximal metatarsophalangeal joint I. The distance of this nerve connection to the medial malleolus is 91.14 mm, and the distance to the incision line is 15.76 mm. CONCLUSIONS: It is suggested that the case presented as an unusual SN variation, which may affect the success of local anesthesia in invasive procedures to the medial part of the foot and could be considered in the evaluation of sensory loss after anteromedial surgical approach to the ankle, should be included in the classification of the cutaneous innervation pattern of the foot.

Anatomical principles of ankle denervation - An update.

BACKGROUND: Denervation is a surgical option in ankle arthrosis when conservative therapy has failed. Sectioning all joint branches is essential for its success. The locations of the articular branches of the saphenous (Sa), tibial (Ti), sural (Su), superficial (Ps) and deep peroneal (Pp) nerves are specified. METHODS: In 16 cryopreserved specimens, the courses of the nerves were prepared. Their articular branches were identified, and their respective locations documented by using a new reference system. RESULTS: The articular branches to the ankle ranged from 5 to 30 cm measured from the foot sole. The Sa should be transected at 22.5 cm, the Su at 20 cm, and the Pp at 15 cm. The Ti should be skeletonized up to 25 cm. Epifascial dissection of the Ps is to be performed below 15 cm. CONCLUSION: The study specifies the joint branches of the ankle in an intraoperatively reproducible reference system and thus minimizes the required skin incisions.

Altered sensory innervation and pain hypersensitivity in a model of young painful arthritic joints: short- and long-term effects.

BACKGROUND: Early life experience can cause long-term alterations in the nociceptive processes underlying chronic pain, but the consequences of early life arthritic joint inflammation upon the sensory innervation of the joint is not known. Here, we measure pain sensitivity and sensory innervation in a young, juvenile and adult rodent model of arthritic joints and test the consequences of joint inflammation in young animals upon adult arthritic pain and joint innervation. METHODS: Unilateral ankle joint injections of complete Freund's adjuvant (CFA) (6-20 µl) were performed in young, postnatal day (P)8, adolescent (P21) and adult (P40) rats. A separate cohort of animals were injected at P8, and again at P40. Hindpaw mechanical sensitivity was assessed using von Frey monofilaments (vF) for 10 days. Nerve fibres were counted in sections through the ankle joint immunostained for calcitonin gene-related peptide (CGRP) and neurofilament 200 kDa (NF200). RESULTS: Ankle joint CFA injection increased capsular width at all ages. Significant mechanical pain hypersensitivity and increased number of joint CGRP + ve sensory fibres occurred in adolescent and adult, but not young, rats. Despite the lack of acute reaction, joint inflammation at a young age resulted in significantly increased pain hypersensitivity and CGRP+ fibre counts when the rats were re-inflamed as adults. CONCLUSIONS: Joint inflammation increases the sensory nociceptive innervation and induces acute pain hypersensitivity in juvenile and adult, but not in young rats. However, early life joint inflammation 'primes' the joint such that adult inflammatory pain behaviour and nociceptive nerve endings in the joint are significantly increased. Early life joint inflammation may be an important factor in the generation and maintenance of chronic arthritic pain.

Neural interfacing architecture enables enhanced motor control and residual limb functionality postamputation.

Despite advancements in prosthetic technologies, patients with amputation today suffer great diminution in mobility and quality of life. We have developed a modified below-knee amputation (BKA) procedure that incorporates agonist-antagonist myoneural interfaces (AMIs), which surgically preserve and couple agonist-antagonist muscle pairs for the subtalar and ankle joints. AMIs are designed to restore physiological neuromuscular dynamics, enable bidirectional neural signaling, and offer greater neuroprosthetic controllability compared to traditional amputation techniques. In this prospective, nonrandomized, unmasked study design, 15 subjects with AMI below-knee amputation (AB) were matched with 7 subjects who underwent a traditional below-knee amputation (TB). AB subjects demonstrated significantly greater control of their residual limb musculature, production of more differentiable efferent control signals, and greater precision of movement compared to TB subjects (P < 0.008). This may be due to the presence of greater proprioceptive inputs facilitated by the significantly higher fascicle strains resulting from coordinated muscle excursion in AB subjects (P < 0.05). AB subjects reported significantly greater phantom range of motion postamputation (AB: 12.47 ± 2.41, TB: 10.14 ± 1.45 degrees) when compared to TB subjects (P < 0.05). Furthermore, AB subjects also reported less pain (12.25 ± 5.37) than TB subjects (17.29 ± 10.22) and a significant reduction when compared to their preoperative baseline (P < 0.05). Compared with traditional amputation, the construction of AMIs during amputation confers the benefits of enhanced physiological neuromuscular dynamics, proprioception, and phantom limb perception. Subjects' activation of the AMIs produces more differentiable electromyography (EMG) for myoelectric prosthesis control and demonstrates more positive clinical outcomes.

Should ice application be replaced with neurocryostimulation for the treatment of acute lateral ankle sprains? A randomized clinical trial.

STUDY DESIGN: Single-blind parallel group randomized clinical trial. OBJECTIVES: To compare the effects of neurocryostimulation (NCS) with those of traditional ice application on functional recovery, pain, edema and ankle dorsiflexion range of motion (ROM) in individuals receiving physiotherapy treatments for acute lateral ankle sprains (LAS). BACKGROUND: Ankle sprain is a very common injury and its management is often costly, with important short- and long-term impacts on individuals and society. As new methods of therapy using cold (cryotherapy) are emerging for the treatment of musculoskeletal conditions, little evidence exists to support their use. NCS, which provokes a rapid cooling of the skin with the liberation of pressured CO2, is a method believed to accelerate the resorption of edema and recovery in the case of traumatic injuries. METHODS: Forty-one participants with acute LAS were randomly assigned either to a group that received in-clinic physiotherapy treatments and NCS (experimental NCS group, n = 20), or to a group that received the same in-clinic physiotherapy treatments and traditional ice application (comparison ice group, n = 21). Primary (Lower Extremity Functional Scale - LEFS) and secondary (visual analog scale for pain intensity at rest and during usual activities in the last 48 h, Figure of Eight measurement of edema, and weight bearing lunge for ankle dorsiflexion range of motion) outcomes were evaluated at baseline (T0), after one week (T1), two weeks (T2), four weeks (T4) and finally, after six weeks (T6). The effects of interventions were assessed using two-way ANOVA-type Nonparametric Analysis for Longitudinal Data (nparLD). RESULTS: No significant group-time interaction or group effect was observed for all outcomes (0.995 ≥ p ≥ 0.057) following the intervention. Large time effects were however observed for all outcomes (p <  0.0001). CONCLUSION: Results suggest that neurocryostimulation is no more effective than traditional ice application in improving functional recovery, pain, edema, and ankle dorsiflexion ROM during the first six weeks of physiotherapy treatments in individuals with acute LAS. LEVEL OF EVIDENCE: Therapy, level 1b. TRIAL REGISTRATION: ClinicalTrials.gov , NCT02945618 . Registered 23 October 2016 - Retrospectively registered (25 participants recruited prior to registration, 17 participants after).

Anatomic Risk to the Neurovascular Structures With a Medially Based All-Inside Syndesmosis Suture Button Technique.

Recent evidence suggests that the use of suture button devices for ankle syndesmosis fixation is increasing. Multiple studies have shown some concern about damaging the greater saphenous neurovasculature with placement of the anchor point on the medial tibial cortex. We hypothesized that an all-inside button deployment technique would allow for a low risk to medial soft tissue structures. A total of 40 syndesmosis suture buttons were placed into 10 separate cadaveric lower limbs, using the newly developed technique. Four suture buttons were sequentially placed from distal to proximal in each limb within the zone of typical syndesmosis fixation, using fluoroscopic guidance. A medial incision was then performed to evaluate the relationship of the suture buttons to the medial soft tissue structures and the medial malleolus. Thirteen of 40 suture buttons (32.5%) were placed anterior, 7 (17.5%) posterior, and 20 (50%) with a portion of the button directly deep to the saphenous vein. Two of 40 buttons (5%) were placed within the tibial periosteum, and 38 (95%) were subfascial and directly superficial to the periosteum. Four of 40 (10%) limbs revealed a perforation in the saphenous vein from the guidepin. In conclusion, risks to the medial neurovascular structures exist with the medial deployment technique, but they appear to be mitigated compared with previous publications. The necessity of a medial incision to evaluate for soft tissue entrapment may not be necessary in all patients, as this technique appears to be safe, accurate, and reproducible.

Is regional ankle block needed in conjunction with general anaesthesia for first ray surgery? A randomised controlled trial of ultrasound guided ankle block versus "blind" local infiltration.

BACKGROUND: Regional anaesthesia is commonly utilised for foot and ankle surgery. Debate remains at to the level of regional anaesthesia that is required. The objective of this study was to evaluate whether surgeon-delivered "blind" local anaesthetic infiltration around the first ray (metatarsal block without ultrasound guidance) was as effective as an ultrasound guided ankle block in providing post-operative analgesia after osseous first ray surgery performed under general anaesthetic. METHODS: 50 patients were recruited to a single surgeon and anaesthetist double-blinded randomised controlled trial at a single-centre. 20mls of 0.5% levobupivacaine was used to perform either an ankle or metatarsal nerve block. RESULTS: Forty-eight patients completed the study: 25 in the ankle block treatment arm and 23 in the metatarsal block arm. The demographics were comparable between groups. There was no statistical difference in visual analogue pain scores at two (21.3 vs 15.2), six (23.6 vs 20.8) and 24 (42.2 vs 50.4) hours following the procedure between the two groups (metatarsal block vs ankle block). Metatarsal block groups had a faster return of normal sensation (2.3 vs 2.8h) but there was no difference in time to safe mobilisation (2.6 vs 2.8h). CONCLUSION: This study demonstrates the efficacy and safety of surgeon delivered "blind" metatarsal block is comparable to an ultrasound guided ankle block for first ray surgery performed under general anaesthetic. LEVEL OF EVIDENCE: 1.

Arthroscopic treatment of lateral ankle instability. Is there a safe zone? An anatomic study.

BACKGROUND: The purpose of this study is to describe the relative location of superficial anatomic landmarks and likely location of structures at risk in order to predict the proximity of the later and avoid their injury during the arthroscopic treatment of lateral ankle instability. METHODS: Fifteen cadaver ankles were dissected. Based on superficial anatomic landmarks, the location and distances to the structures at risk (extensor tendons, peroneus tertius, peroneal tendons, main branch or intermediate branch of the superficial peroneal nerve, and the sural nerve) were measured. RESULTS: The distance from the lateral malleolus along the peroneus brevis to its intersection by the sural nerve was 38.5±10.5mm and from it to the superficial peroneal nerve was 32.0±7.4mm. Based on the minimum distances, a rectangular area of 25mm×22mm was obtained. The anterior talofibular ligament and the proximal border of the inferior extensor retinaculum were within this area. CONCLUSIONS: Our study suggests that based on superficial anatomic landmarks, it is possible to define an anatomic area in order to avoid structures at risk. In addition to the usual precautions, these anatomical references may contribute to lower the complication rate associated to the arthroscopic treatment of lateral ankle instability.

Comparison of Therapeutic Ultrasound and Radial Shock Wave Therapy in the Treatment of Plantar Flexor Spasticity After Stroke: A Prospective, Single-blind, Randomized Clinical Trial.

BACKGROUND: This study aimed to compare the effects of therapeutic ultrasound (US) and radial extracorporeal shock wave therapy (rESWT) in the treatment of plantar flexor spasticity after stroke. MATERIALS AND METHODS: In this prospective, single-blind, randomized clinical trial, 32 patients (age range 42-78 years; male 19) with stroke were randomly divided into two groups: The US group (n = 16) received the continuous ultrasound, intensity 1.5 w/cm2, frequency 1 MHz, and duration 10 minutes. The rESWT group (n = 16) was treated with rESWT, 0.340 mJ/mm2, 2000 shots. Both groups received the treatments for 1 session. The H-reflex tests of Hmax/Mmax ratio and H-reflex latency, the Modified Modified Ashworth Scale (MMAS), active range of motion (AROM), passive range of motion (PROM), passive plantar flexor torque (PPFT), and the timed "up and go" test (TUG) were blinded assessed at baseline (T0), immediately post-treatment (T1), and one hour follow-up (T2). RESULTS: The H-reflex tests did not improve across the groups. However, the MMAS spasticity scores, AROM and PROM, PPFT, and TUG improved significantly within groups. The results found no significant differences between groups for all outcome measures. CONCLUSIONS: The US and rESWT had similar effects, and the rESWT was not more effective than the US in improving ankle plantar flexor spasticity after stroke.

Intraneural ganglion cysts of the lower limb. / Intraneurale Ganglionzysten der unteren Extremität.

BACKGROUND: Intraneural ganglion cysts are rare. They affect the peripheral nerves. According to the most widely accepted theory (articular/synovial theory), the cysts are formed from a capsular defect of an adjacent joint, so that synovial fluid spreads along the epineurium of a nerve branch. This leads to diverse neurological symptoms. We will illustrate this disease based on three of our own cases. METHODS: Patients were examined between 2011 and 2018 using lower limb MRI. MRI scans were also performed for the follow-up examinations. CASE STUDIES AND DISCUSSION: The patients had many symptoms. We were able to accurately detect the intraneural ganglion cysts on MRI and provide the treating surgeons with the basis for the operation to be performed. The success of surgical therapy depends on the resection of the nerve endings supplying the joint as the only way to treat the origin of the disease and prevent recurrence. Based on our case studies, we can support the commonly favored articular/synovial theory. KEY POINTS: · Intraneural ganglion cysts can cause diverse neurological symptoms depending on their location.. · The pathogenesis is reasonably explained by the articular/synovial theory, which states that cysts are the result of a capsular defect of a joint.. · MRI is the method of choice for diagnosing intraneural ganglion cysts. However, ultrasound is also important.. · Surgery is the only curative treatment with treatment success being dependent on ligature of the nerve endings supplying the articular branch.. CITATION FORMAT: · Fricke T, Schmitt AD, Jansen O. Intraneural ganglion cysts of the lower limb. Fortschr Röntgenstr 2019; 191: 732 - 738.

Closed-loop functional optogenetic stimulation.

Optogenetics has been used to orchestrate temporal- and tissue-specific control of neural tissues and offers a wealth of unique advantages for neuromuscular control. Here, we establish a closed-loop functional optogenetic stimulation (CL-FOS) system to control ankle joint position in murine models. Using the measurement of either joint angle or fascicle length as a feedback signal, we compare the controllability of CL-FOS to closed-loop functional electrical stimulation (CL-FES) and demonstrate significantly greater accuracy, lower rise times and lower overshoot percentages. We demonstrate orderly recruitment of motor units and reduced fatigue when performing cyclical movements with CL-FOS compared with CL-FES. We develop and investigate a 3-phase, photo-kinetic model to elucidate the underlying mechanisms for temporal variations in optogenetically activated neuromusculature during closed-loop control experiments. Methods and insights from this study lay the groundwork for the development of closed-loop optogenetic neuromuscular stimulation therapies and devices for peripheral limb control.

Limping on split-belt treadmills implies opposite kinematic and dynamic lower limb asymmetries.

Walking on a split-belt treadmill (each of the two belts running at a different speed) has been proposed as an experimental paradigm to investigate the flexibility of the neural control of gait and as a form of therapeutic exercise. However, the scarcity of dynamic investigations challenges the validity of the available findings. The aim of the present study was to investigate the dynamic asymmetries of lower limbs of healthy adults during adaptation to gait on a split-belt treadmill. Ten healthy adults walked on a split-belt treadmill mounted on force sensors, with belts running either at the same speed ('tied' condition) or at different speeds ('split' condition, 0.4 vs. 0.8 or 0.8 vs. 1.2 m/s). The sagittal power and work provided by ankle, knee and hip joints, joint rotations, muscle lengthening, and surface electromyography were recorded simultaneously. Various tied/split walking sequences were requested. In the split condition a marked asymmetry between the parameters recorded from each of the two lower limbs, in particular from the ankle joint, was recorded. The work provided by the ankle (the main engine of body propulsion) was 4.8 and 2.2 times higher (in the 0.4 vs. 0.8, and 0.8 vs. 1.2 m/s conditions, respectively) compared with the slower side, and 1.2 and 1.1 times higher compared with the same speed in the tied condition. Compared with overground gait in hemiplegia, split gait entails an opposite spatial and dynamic asymmetry. The faster leg mimics the paretic limb temporally, but the unimpaired limb from the spatial and dynamic point of view. These differences challenge the proposed protocols of split gait as forms of therapeutic exercise.

The potential role of sciatic nerve stiffness in the limitation of maximal ankle range of motion.

It is a long held belief that maximal joint range of motion (ROM) is restricted by muscle tension. However, it exists indirect evidence suggesting that this assumption may not hold true for some joint configurations where non-muscular structures, such as the peripheral nerves, are stretched. Direct evidences are lacking. This study aimed to determine whether a static stretching aiming to load the sciatic nerve without stretch within plantar flexors is effective to: (i) alter nerve stiffness; and (ii) increase the ankle's maximal ROM. Passive maximal ankle ROM in dorsiflexion was assessed with the hip flexed at 90° (HIP-flexed) or neutral (HIP-neutral, 0°). Sciatic nerve stiffness was estimated using shear wave elastography. Sciatic nerve stretching induced both a 13.3 ± 7.9% (P < 0.001) decrease in the nerve stiffness and a 6.4 ± 2.6° increase in the maximal dorsiflexion ROM assessed in HIP-flexed. In addition, the decrease in sciatic nerve stiffness was significantly correlated with the change in maximal ROM in dorsiflexion (r = -0.571, P = 0.026). These effects occurred in the absence of any change in gastrocnemius medialis and biceps femoris stiffness, and ankle passive torque. These results demonstrate that maximal dorsiflexion ROM can be acutely increased by stretching the sciatic nerve, without altering the muscle stiffness.

Kinematic and kinetic benefits of implantable peroneal nerve stimulation in people with post-stroke drop foot using an ankle-foot orthosis.

BACKGROUND: Contralesional 'drop foot' after stroke is usually treated with an ankle-foot orthosis (AFO). However, AFOs may hamper ankle motion during stance. Peroneal functional electrical stimulation (FES) is an alternative treatment that provides active dorsiflexion and allows normal ankle motion. Despite this theoretical advantage of FES, the kinematic and kinetic differences between AFO and FES have been scarcely investigated. OBJECTIVE: To test whether walking with implanted FES leads to improvements in stance stability, propulsion, and swing initiation compared to AFO. METHODS: A 4-channel peroneal nerve stimulator (ActiGait ®) was implanted in 22 chronic patients after stroke. Instrumented gait analyses were performed during comfortable walking up to 26 weeks (n = 10) or 52 weeks (n = 12) after FES-system activation. Kinematics of knee and ankle (stance and swing phase) and kinetics (stance phase) of gait were determined, besides spatiotemporal parameters. Finally, we determined whether differences between devices regarding late stance kine(ma)tics correlated with those regarding the swing phase. RESULTS: In mid-stance, knee stability improved as the peak knee extension velocity was lower with FES (ß = 18.1°/s, p = 0.007), while peak ankle plantarflexion velocity (ß = -29.2°/s, p = 0.006) and peak ankle plantarflexion power (ß = -0.2 W/kg, p = 0.018) were higher with FES compared to AFO. With FES, the ground reaction force (GRF) vector at peak ankle power (i.e., 'propulsion') was oriented more anteriorly (ß = -1.1°, p = 0.001). Similarly, the horizontal GRF (ß = -0.8% body mass, p = 0.003) and gait speed (ß = 0.03 m/s, p = 0.015) were higher. An increase in peak ankle plantarflexion velocity and a more forward oriented GRF angle during late stance were moderately associated with an increase in hip flexion velocity during initial swing (rs = 0.502, p = 0.029 and rs = 0.504, p = 0.028, respectively). CONCLUSIONS: This study substantiates the evidence that implantable peroneal FES as a treatment for post-stroke drop foot may be superior over AFO in terms of knee stability, ankle plantarflexion power, and propulsion.

Effect of oral baclofen on spasticity poststroke: responders versus non-responders.

Objective To assess quantitatively the efficacy of oral baclofen for spasticity poststroke. Methods The participants were 29 persons poststroke with increased resistance to passive ankle dorsiflexion and ankle clonus on clinical assessment. Baclofen was administered at 20 mg/day for 1 week. The ankle joint was passively dorsiflexed at either 5°/s (slow stretch) or 90°/s (fast stretch) by a custom-built device. The ankle joint angle and resistive torque were measured during the ramp-and-hold stretch, with gastrocnemius electromyogram. The main outcome measures were the numbers of ankle clonus during hold, and the torques at 10° of ankle dorsiflexion in slow stretch (T-slow) and fast stretch (T-fast). Moreover, the velocity-dependent torque (ΔT = T-fast - T-slow) was compared between before and after oral baclofen. Results The numbers of ankle clonus, T-slow, T-fast, and ΔT for all participants did not exhibit significant differences between before and after baclofen administration. However, reduction in the number of ankle clonus of five or more was accompanied with a reduction in ΔT (4.0 ± 1.8 Nm) in three participants (the responders). Conclusion Although the responder rate was low, some participants responded to oral baclofen. Thus, a short-term trial of oral baclofen, and quantitative and electrophysiological assessments of muscle tone and ankle clonus are recommended.

Risk of injury to the sural nerve during posterolateral approach to the distal tibia: An ultrasound simulation study.

When surgeons operate on the foot and ankle, the most common complication that may arise is injury of the cutaneous nerves. The sural nerve (SN) is potentially at risk of being injured when treating fractures involving the distal tibia using the posterolateral approach. The aim of this study was to evaluate how differences in length and position of the surgical treatment of fractures involving the distal tibia can affect the risk of SN injury. The study involved 40 healthy volunteers (n = 80 lower limbs). Ultrasound simulation of each potential surgical incision site was used to locate the SN and to assess the risk of injury. The study showed that the SN predominantly travels more posteriorly at levels more proximal from the tip of the lateral malleolus. At these more proximal points of the SN's course, it was proven that there was an overall increased incidence of iatrogenic injury to the SN in incisions made closer to the Achilles tendon. Based on these results, a quasi 3 dimensional figure was created showing the anatomical structures of this region to identify areas at high risk for SN injury. By revealing how length and position of the surgical incision can influence the risk of SN injury, we hope to provide information to surgeons on the optimal technique to avoid iatrogenic SN injury while operating on the distal tibia via a posterolateral approach. Clin. Anat. 31:870-877, 2018. © 2018 Wiley Periodicals, Inc.

Immediate effects of talus-stabilizing taping on balance and gait parameters in patients with chronic stroke: a cross-sectional study.

BACKGROUND: Talus-stabilizing taping (TST) may improve ankle range of motion and gait performance by providing a posterior-inferior talar glide in a closed-chain dorsiflexion position. OBJECTIVES: This study aimed to investigate the immediate effects of TST on balance and gait parameters in patients with chronic stroke. METHODS: Twenty post-stroke patients participated in this study. Each participant performed tests under three conditions (TST, barefoot, and conventional ankle-foot orthosis [AFO]), in random order. Before testing, the patients walked for 10 min under the three conditions, followed by a 5 min rest period. The outcome measures were static balance ability (SBA), timed up-and-go (TUG) test results, and gait parameters evaluated using a 6-m-long gait mat. One-way repeated measures analysis of variance was used to determine the difference in balance and gait parameters under the three conditions. RESULTS: SBA more significantly improved in the TST condition than in the barefoot condition. SBA more significantly improved in the conventional AFO condition than in the barefoot condition. The TUG test results more significantly improved in the TST condition than in the conventional AFO and barefoot conditions. Walking speed, cadence, and affected side and unaffected side step and stride lengths more significantly improved in the TST condition than in the conventional AFO and barefoot conditions. CONCLUSIONS: This study used a cross-sectional method and demonstrated that TST improves SBA, TUG, gait speed, cadence, step length, and stride length in patients with chronic stroke.

Attention demands of postural control in non-specific chronic low back pain subjects with low and high pain-related anxiety.

Impaired postural control in chronic low back pain (CLBP) has been attributed to deficits in sensory and motor functions. However, it is not known if pain-related anxiety affects motor and cognitive function of postural control. The aim of this study was to compare the interactive effects of postural and cognitive function in CLBP patients with high and low pain-related anxiety and healthy subjects. Thirty-eight patients with nonspecific CLBP (19 with low and 19 with high pain-related anxiety levels) and 20 asymptomatic subjects participated. Postural control was assessed by center of pressure (COP) parameters including mean total sway velocity, area, anterior-posterior (A-P), and medial-lateral (Med-Lat) range. Postural task was assessed during four conditions (eyes open with and without ankle vibration-eyes closed with and without ankle vibrations). Participants performed the postural task with or without auditory Stroop task. Average reaction time and error ratio of auditory Stroop test were calculated as measures of the cognitive task performance. Significantly reduced sway area was observed in CLBP patients with high pain-related anxiety and control subjects during the dual-task condition as compared with the single task. In addition, A-P range was significantly reduced in CLBP patients with high pain-related anxiety during dual tasking when eyes were closed with ankle vibration. In addition, only the CLBP subjects with high pain-related anxiety showed significantly longer reaction times by increasing the difficulty of standing postural task. Pain-related anxiety may influence the postural cognitive interactions in CLBP patients. Furthermore, it may be considered as a contributing factor for postural strategies adopted by CLBP patients.

Neurovascular and tendon injuries due to ankle arthroscopy portals: a meta-analysis of interventional cadaveric studies.

Neurovascular and tendon structures are considered at risk when performing ankle arthroscopy. Injury rate and distance from portals to such structures varied in the literature. The aim of this meta-analysis is to evaluate the injury risk of these structures in terms of proximity and injury prevalence. Thirteen studies including 184 cadaveric ankle arthroscopy procedures met the inclusion criteria. The antero-central portal exhibited the highest frequencies of nerve/vessel proximity and nerve/vessel missed injuries. Weighted mean distances were as follows: 2.76 ± 2.37 mm for the superficial fibular nerve (SFN) to the antero-lateral portal, 8.13 ± 2.45 mm for the saphenous nerve to the antero-medial portal, 2.1 ± 1.7 mm for the dorsalis pedis artery (DPA) to the antero-central (AC) portal, 6.84 ± 2.59 mm for the sural nerve to the postero-lateral portal. Distances to the postero-medial portal were 7.82 ± 2.98 and 11.03 ± 3.2 mm for the posterior tibial nerve and the posterior tibial artery, respectively. A total of 14 (10.3%) nerve injuries and 17 (12.5%) missed nerve injuries with a cumulative frequency of 22.8% of nerve structure at high risk. The SFN was the most vulnerable (10.3% of injury/missed injury), and it was the closest nerve to a portal. Vascular involvement consisted of 2 (1.5%) injuries and 12 (8.8%) missed injuries with the DPA being the most vulnerable (20%) through the AC portal. Tendon injuries were found in 8.7% procedure acts. The injury rates of extra-articular structures were found to be higher than previously reported in clinical literature. Apart from clinical studies, distance to portals and missed injuries of these structures could be evaluated. This cadaveric meta-analysis yielded more accurate results over the proximity and potential injury risk of ankle noble structure and should incite surgeons for more attention during portal placement. Such anatomical meta-analyses could offer an excellent statistical model of evidence synthesis when assessing injury risk in mini-invasive surgeries.

The relationship between the sensory responses to ankle-joint loading and corticomotor excitability.

PURPOSE: Maintaining joint stability is dependent on the ability of the nervous system to sense and react to potentially injurious loads. In attempts to understand the neurophysiologic mechanisms underlying joint stability, this afferent and efferent activity has been quantified separately at the cortical, segmental and peripheral levels using various electrophysiologic techniques in vivo. However, no studies have attempted to quantify sensory and motor activation at multiple levels of the nervous system in a single subset, to understand potential adaptations for optimizing joint stability. MATERIALS AND METHODS: Muscle spindle afferent activity and sensory cortex event-related desynchronization were quantified during ankle-joint loading; and motor excitability was assessed through transcranial magnetic stimulation and the Hoffmann reflex in a subset of 42 able-bodied individuals. Microneurography and electroencephalography were used to collect the muscle spindle afferent and sensory cortex activation, respectively, as joint load was applied using an ankle arthrometer. Separately, motor-evoked potentials were obtained from the tibialis anterior (TA) and soleus (SOL) using transcranial magnetic stimulation over the motor cortex, and compared to the reflexive responses evoked via sciatic nerve electrical stimulation. RESULTS: Correlation coefficients revealed significant correlations between the motor threshold of the soleus and early muscle spindle afferent activity (r = -0.494) and early cortical event-related desynchronization (r = 0.470), as well as tibialis anterior motor-evoked potential size and late muscle spindle afferent activity (r = 0.499). CONCLUSIONS: The results of this study highlight the nervous system's capability to offset motor output based on the volume of sensory input at the segmental and cortical levels.