Mechanoreceptors of the ligaments and tendons around the knee

Proprioceptive inputs from the joints and limbs arise from mechanoreceptors in the muscles, ligaments and tendons. The knee joint has a wide range of movements, and proper neuroanatomical organization is critical for knee stability. Four ligaments (the anterior (ACL) and posterior (PCL) cruciate ligaments and the medial (MCL) and lateral (LCL) collateral ligaments) and four tendons (the semitendinosus (STT), gracilis (GT), popliteal (PoT), and patellar (PaT) tendons) from eight fresh frozen cadavers were harvested. Each harvested tissue was divided into its bone insertion side and its tendinous part for immunohistochemical examination using S100 staining. Freeman–Wyke's classification was used to identify the mechanoreceptors. The mechanoreceptors were usually located close to the bone insertion. Free nerve endings followed by Ruffini endings were the most common mechanoreceptors overall. No Pacini corpuscles were observed; free nerve endings and Golgi‐like endings were most frequent in the PCL (PCL‐PaT: P = 0.0.1, PCL‐STT: P = 0.00), and Ruffini endings in the popliteal tendon (PoT‐PaT: P = 0.00, Pot‐STT: P = 0.00, PoT‐LCL: P = 0.00, PoT‐GT: P = 0.00, PoT‐ACL: P = 0.09). The cruciate ligaments had more mechanoreceptors than the medial structures (MS) or the patellar tendon (CR‐Pat: P = 0.000, CR‐MS: P = 0.01). The differences in mechanoreceptor distributions between the ligaments and tendons could reflect the different roles of these structures in the dynamic coordination of knee motion. Clin. Anat. 29:789–795, 2016. © 2016 Wiley Periodicals, Inc.     

Effect of elastic bandage on postural control in subjects with chronic ankle instability: a randomised clinical trial

Purpose: To report the immediate and prolonged (one week) effects of elastic bandage (EB) on balance control in subjects with chronic ankle instability.

Material and methods: Twenty-eight individuals successfully completed the study protocol, of whom 14 were randomly assigned to the EB group (7 men, 7 women) and 14 were assigned to the non-standardised tape (NST) group (9 men, 5 women). To objectively measure postural sway we used computerised dynamic posturography (CDP) with sensory organisation test (SOT) and unilateral stance (US) test. We analysed the following SOT parameters: the composite SOT score, the composite SOT strategy and the SOT condition 2 and its strategy. In addition, we studied the centre of gravity (COG) sway velocity with open eyes and close eyes during the US test.

Results: Repeated measures ANOVA showed a significant effect for time in composite SOT score (F=?34.98; p=?<0.01), composite SOT strategy (F=?12.082; p=?0.02), and COG sway with open eyes (F=?3.382; p=?0.039) in EB group and NST group. Therefore, there were improvements in balance control after bandage applications (defined as better scores in SOT parameters and decreased COG sway in US test). However, no differences between groups were observed in the most relevant parameters.

Conclusions: This study did not observe differences between EB and NST during the follow-up in the majority of measurements. Several outcome measures for SOT and US tests improved in both groups immediately after bandage applications and after one week of use. EB of the ankle joint has no advantage as compared to the non-standardised tape.

• Implications for rehabilitation

• Elastic bandage (EB) of the ankle joint has no advantage as compared to the non-standardised tape.

• The effects of the bandages could be due to a greater subjective sense of security.

• It is important to be prudent with the use of bandage, since a greater sense of safety could also bring with it a greater risk of injury.

• The application of the bandage on subjects with chronic ankle instability (CAI) should be prolonged and used alongside other physiotherapy treatments.

     

Long-term plasticity in adult somatosensory cortex: functional reorganization after surgical removal of an arteriovenous malformation

The temporal scale of neuroplasticity following acute alterations in brain structure due to neurosurgical intervention is still under debate. We conducted a longitudinal study with the objective of investigating the postoperative changes in a patient who underwent cerebrovascular surgery and who subsequently lost proprioception in the fingers of her right hand. The results show increased activation in contralesional somatosensory areas, additional recruitment of premotor and posterior parietal areas, and changes in functional connectivity with left postcentral gyrus. These findings demonstrate long-term modifications of cortical organization and as such have important implications for treatment strategies for patients with brain injury.     

Comparing limb proprioception and oculomotor signals during hand-guided saccades

We previously showed that saccades tend to overshoot briefly flashed targets that were manually displaced in the dark (Ren et al. 2006). However it was not clear if the overshoot originated from a sensory error in measuring hand displacement or from a premotor error in saccade programming, because gaze and hand position started at the same central position. Here, we tested between these hypotheses by dissociating the initial eye and hand position. Five hand/target positions (center, far, near, right, left) on a frontally-placed horizontal surface were used in four paradigms: Center or Peripheral Eye-hand Association (CA or PA, both gaze and right hand started from the center or a same peripheral location) and Hand or Eye Dissociation (HD or ED, hand or gaze started from one of three non-target peripheral locations). Subjects never received any visual feedback about the final target location and the subjects’ hand displacement. In the CA paradigm, subjects showed the same overshoot that we showed previously. However, changing both initial eye and hand positions relative to the final target (PA) affected the pattern, significantly altering the directions of overshoots. Changing only the initial position of hand (HD) did not have this effect, whereas changing only initial eye position (ED) had the same effect as the PA condition (CA ≈ HD, PA ≈ ED). Furthermore, multiple regression analysis showed that the direction of the ideal saccade contributed significantly to the endpoint direction error, not the direction of the hand path. These results suggest that these errors do not primarily arise from misestimates of the hand trajectory, but rather from a process of comparing the initial eye position and the limb proprioceptive signal during saccade programming.     

Immunofluorescence analysis of sensory nerve endings in the interosseous membrane of the forearm

The human interosseous membrane (IOM) is a fundamental stabilizer during forearm rotation. To investigate the dynamic aspects of forearm stability, we analyzed sensory nerve endings in the IOM. The distal oblique bundle (DOB), the distal accessory band (DAB), the central band (CB), the proximal accessory band (PAB), the dorsal oblique accessory cord (DOAC) and the proximal oblique cord (POC) were dissected from 11 human cadaver forearms. Sensory nerve endings were analyzed at two levels per specimen as total cell amount/mm² after immunofluorescence staining with low-affinity neurotrophin receptor p75, protein gene product 9.5, S-100 protein and 4′,6-diamidino-2-phenylindole on an Apotome microscope, according to Freeman and Wyke’s classification. Sensory nerve endings were significantly more commonly found to be equally distributed throughout the structures, rather than being epifascicular, interstitial, or close to the insertion into bone (P ≤ 0.001, respectively). Free nerve endings were the predominant mechanoreceptor in all six structures, with highest density in the DOB, followed by the POC (P ≤ 0.0001, respectively). The DOB had the highest density of Pacini corpuscles. The DOAC and CB had the lowest amounts of sensory innervation. The high density of sensory corpuscles in the DOB, PAB and POC indicate that proprioceptive control of the compressive and directional muscular forces acting on the distal and proximal radioulnar joints is monitored by the DOB, PAB and POC, respectively, due to their closed proximity to both joints, whereas the central parts of the IOM act as structures of passive restraint.     

移动式平板训练对脑卒中偏瘫患者的运动功能及日常生活活动能力的影响

目的：观察移动式平板训练对脑卒中偏瘫患者本体感觉障碍的运动能力及日常生活活动能力的影响。方法：脑卒中偏瘫患者30例随机分为观察组和对照组各15例,2组患者均给予常规药物治疗及康复训练,观察组加用移动式平板训练进行本体感觉训练,对照组加用神经肌肉本体感觉促进疗法（PNF）进行治疗。治疗前后采用Tecnobody本体感觉评估系统（ATE及Time值）、Fugl-Meyer下肢运动功能评定量表（FMA）、Berg平衡量表（BBS）、改良Barthel指数评定表（MBI）评估2组患者的本体感觉、下肢运动功能、平衡能力及日常生活活动能力。 结果：治疗8周后,2组ATE值及Time值均较治疗前明显降低（P<0.05）,且观察组更低于对照组（P<0.05）;2组FMA、BBS、MBI评分均较治疗前明显提高（P<0.05）,且观察组FMA评分较对照组明显提高（P<0.05）,但BBS、MBI评分2组间比较差异无统计学意义。结论：移动式平板训练对脑卒中偏瘫患者本体感觉及下肢运动功能的疗效优于PNF疗法;对于平衡能力及日常生活活动能力的改善,两者未见明显区别。     

早期本体感觉训练对全膝关节置换术后患者步行能力的影响

[目的]观察本体感觉训练对全膝关节置换术后患者步行能力的影响。[方法]将40例全膝关节置换术后第3周的患者随机分为对照组及治疗组,对照组进行常规康复训练,治疗组在常规康复训练的基础上,增加本体感觉训练,包括闭链运动训练及Mtd视觉及听觉的反馈平衡训练,并于术后第3周、第4周末及第6周末进行起立-行走计时测试(timed"up and go"test,TUGT)、膝关节百分评分系统(the hospital for special surgery,HSS)及Berg平衡量表(Berg balance scale,BBS)评测。计数资料采用t检验,计量资料采用u检验。[结果]本体感觉训练前,两组患者的上述评测结果比较差异无显著性意义(P>0.05),而在本体感觉训练后,尤其在术后第6周末,治疗组评测结果有明显改善,组间、组内比较差异有统计学意义(P<0.05)。[结论]早期本体感觉训练可有效地改善患者的躯干、膝关节的动静态平衡能力,恢复患膝运动功能,提高独立步行能力。     

Late spinal dislocation after treatment of spinal arteriovenous malformation. A case of Charcot spinal arthropathy

Neuropathic arthropathy of the spine is a destructive condition of the spine which is secondary to a loss of the protective proprioceptive reflexes. In the majority of cases, it occurs in patients who have suffered from traumatic medullary lesions and is responsible for destruction of the vertebral bodies and considerable spinal deformity. We report a case of neurogenic lumbar arthropathy in a patient with a spinal arteriovenous malformation. This vascular lesion caused considerable disturbances of proprioception. The course was favorable with regard to the deformity after correction and fusion by posterior approach.