Carpal and cubital tunnel and other, rarer nerve compression syndromes

BACKGROUND

Carpal tunnel syndrome is by far the most common peripheral nerve compression syndrome, affecting approximately one in every six adults to a greater or lesser extent. Splitting the flexor retinaculum to treat carpal tunnel syndrome is the second most common specialized surgical procedure in Germany. Cubital tunnel syndrome is rarer by a factor of 13, and the other compression syndromes are rarer still.

METHODS

This review is based on publications retrieved by a selective literature search of PubMed and the Cochrane Library, along with current guidelines and the authors' clinical and scientific experience.

RESULTS

Randomized controlled trials have shown, with a high level of evidence, that the surgical treatment of carpal tunnel syndrome yields very good results regardless of the particular technique used, as long as the diagnosis and the indication for surgery are well established by the electrophysiologic and radiological findings and the operation is properly performed. The success rates of open surgery, and the single-portal and dual-portal endoscopic methods are 91.6%, 93.4% and 92.5%, respectively. When performed by experienced hands, all these procedures have complication rates below 1%. The surgical treatment of cubital tunnel syndrome has a comparably low complication rate, but worse results overall. Neuro-ultrasonography and magnetic resonance imaging (neuro-MRI) are increasingly being used to complement the diagnostic findings of electrophysiologic studies.

CONCLUSION

Evidence-based diagnostic methods and treatment recommendations are now available for the two most common peripheral nerve compression syndromes. Further controlled trials are needed for most of the rarer syndromes, especially the controversial ones.

IR, Raman, and NMR studies of the short-range structures of 0.5Na2S + 0.5[xGeS2 + (1-x)PS(5/2)] mixed glass-former glasses

A nonlinear and nonadditive composition-dependent change of the ionic conductivity in mixed glass-former (MGF) glasses when one glass former, such as PS(5/2), is replaced by a second glass former, such as GeS2, at constant alkali modifier concentrations, such as Na2S, is known as the mixed glass-former effect (MGFE). Alkali ion conducting glasses are of particular interest for use as solid electrolytes in alkali-based all-solid-state batteries because sulfide amorphous materials have significantly higher alkali ion conductivities than their oxide glass counterparts. In this study of the ternary MGF system Na2S + GeS2 + PS(5/2), we report the careful structural characterization of these glasses using a combination of vibrational, infrared (IR), Raman, and nuclear magnetic resonance (NMR) spectroscopies. Our measurements of the 0.5Na2S + 0.5[xGeS2 + (1-x)PS(5/2)] MGF system show that this glass system exhibits a strongly negative MGFE and non-Arrhenius ionic conductivities. While this negative MGFE in the Na(+) ion conductivity makes these glasses less attractive for use in solid-state Na batteries, the structural origin of this effect is important to better understand the mechanisms of ion conduction in the glassy state. For these reasons, we have examined the structures of ternary 0.5Na2S + 0.5[xGeS2 + (1-x)PS(5/2)] glasses using Raman, IR, and (31)P MAS NMR spectroscopies. In these studies, it is found that the substitution of PS(5/2) by GeS2, that is, increasing x, leads to unequal sharing of the Na(+) in these glasses. Thus, in all MGF compositions, phosphorus groups are associated with a disproportionately larger fraction, f(Na(P)) > 0.5(1 - x), of the Na(+) ions while the germanium groups are found to be Na(+)-deficient relative to the total amount of Na(+) present in the glass, that is, f(Na(Ge)) < 0.5x. From the spectroscopic study of these glasses, a short-range order (SRO) structural model is developed for these glasses and is based on the germanium and phosphorus SRO groups in these glasses as a first step in understanding the unique negative MGFE and non-Arrhenius behavior in the Na(+) ion conductivity in these glasses.

Quantitative vibrational dynamics of the metal site in a tin porphyrin: an IR, NRVS, and DFT study

We used a newer, synchrotron-based, spectroscopic technique (nuclear resonance vibrational spectroscopy, NRVS) in combination with a more traditional one (infrared absorption, IR) to obtain a complete, quantitative picture of the metal center vibrational dynamics in a six-coordinated tin porphyrin. From the NRVS (119)Sn site-selectivity and the sensitivity of the IR signal to (112)Sn/(119)Sn isotope substitution, we identified the frequency of the antisymmetric stretching of the axial bonds (290 cm(-1)) and all the other vibrations involving Sn. Experimentally authenticated density functional theory (DFT) calculations aid the data interpretation by providing detailed normal mode descriptions for each observed vibration. These results may represent a starting point toward the characterization of the local vibrational dynamics of the metallic site in tin porphyrins and compounds with related structures. The quantitative complementariness between IR, NRVS, and DFT is emphasized.

[The new S2k AWMF guideline for the treatment of Bell's palsy in commented short form]

A new S2k AWMF guideline for the treatment of idiopathic facial palsy has been published. An accurate differential diagnosis is indispensable as 25-40% of all facial palsy cases are of non-idiopathic origin. It is explicitly recommended to treat patients with idiopathic facial palsy with steroids. Steroids favour a complete recovery, decrease the risk of synkinesis, autonomic sequelae and contractures. Adjuvant antiviral therapy cannot be recommended. On current data there is not sufficient evidence that the combination of steroids with antiviral drugs has a benefit for the patients. Even when not supported by randomized trials, adjuvant symptomatic therapy to protect the cornea and to avoid complications is recommended. There is no scientific evidence that physical therapy has any benefit but it should be taken into account because of psychological reasons. A benefit of acupuncture has not been proven. If eye closure remains incomplete as result of defective healing, one therapeutic option is lid loading of the upper eye lid. Moreover, in case of severe persistent palsy, several well-established microsurgical nerve and muscle plasty procedures are available.

Non-Arrhenius ionic conductivities in glasses due to a distribution of activation energies

Previously observed non-Arrhenius behavior in fast ion conducting glasses [J. Kincs and S. W. Martin, Phys. Rev. Lett. 76, 70 (1996)] occurs at temperatures near the glass transition temperature, T(g), and is attributed to changes in the ion mobility due to ion trapping mechanisms that diminish the conductivity and result in a decreasing conductivity with increasing temperature. It is intuitive that disorder in glass will also result in a distribution of the activation energies (DAE) for ion conduction, which should increase the conductivity with increasing temperature, yet this has not been identified in the literature. In this Letter, a series of high precision ionic conductivity measurements are reported for 0.5Na(2)S + 0.5[xGeS(2) + (1-x)PS(5/2)] glasses with compositions ranging from 0 ≤ x ≤ 1. The impact of the cation site disorder on the activation energy is identified and explained using a DAE model. The absence of the non-Arrhenius behavior in other glasses is explained and it is predicted which glasses are expected to accentuate the DAE effect on the ionic conductivity.

Cubital tunnel syndrome - a review and management guidelines

Cubital tunnel syndrome (CuTS) is the second most common peripheral nerve compression syndrome. In German-speaking countries, cubital tunnel syndrome is often referred to as sulcus ulnaris syndrome (retrocondylar groove syndrome). This term is anatomically incorrect, since the site of compression comprises not only the retrocondylar groove but the cubital tunnel, which consists of 3 parts: the retrocondylar groove, partially covered by the cubital tunnel retinaculum (lig. arcuatum or Osborne ligament), the humeroulnar arcade, and the deep flexor/pronator aponeurosis. According to Sunderland , cubital tunnel syndrome can be differentiated into a primary form (including anterior subluxation of the ulnar nerve and compression secondary to the presence of an anconeus epitrochlearis muscle) and a secondary form caused by deformation or other processes of the elbow joint. The clinical diagnosis is usually confirmed by nerve conduction studies. Recently, the use of ultrasound and MRI have become useful diagnostic tools by showing morphological changes in the nerve within the cubital tunnel. A differential diagnosis is essential in atypical cases, and should include such conditions as C8 radiculopathy, Pancoast tumor, and pressure palsy. Conservative treatment (avoiding exposure to external noxes and applying of night splints) may be considered in the early stages of cubital tunnel syndrome. When nonoperative treatment fails, or in patients who present with more advanced clinical findings, such as motor weakness, muscle atrophy, or fixed sensory changes, surgical treatment should be recommended. According to actual randomized controlled studies, the treatment of choice in primary cubital tunnel syndrome is simple in situ decompression, which has to be extended at least 5-6 cm distal to the medial epicondyle and can be performed by an open or endoscopic technique, both under local anesthesia. Simple decompression is also the therapy of choice in uncomplicated ulnar luxation and in most post-traumatic cases and other secondary forms. When the luxation is painful, or when the ulnar nerve actually "snaps" back and forth over the medial epicondyle of the humerus, subcutaneous anterior transposition may be performed. In cases of severe bone or tissue changes of the elbow (especially with cubitus valgus), the anterior transposition of the ulnar nerve may again be indicated. In cases of scarring, submuscular transposition may be preferred as it provides a healthy vascular bed for the nerve as well as soft tissue protection. Risks resulting from transposition include compromise in blood flow to the nerve as well as kinking of the nerve caused by insufficient proximal or distal mobilization. In these cases, revision surgery is necessary. Epicondylectomy is not common, at least in Germany. Recurrence of compression on the ulnar nerve at the elbow may occur. This review is based on the German Guideline "Diagnose und Therapie des Kubitaltunnelsyndroms" ( www.leitlinien.net ).

Structural Elucidation of Alkali Fluorozirconate Glasses Using High-Resolution Solid State NMR

The structure of two compositional series of ZrF4-LaF3-BaF2-MF (M = Li or Na) glasses has been examined by 19F magic-angle spinning (MAS)-NMR spectroscopy. From a detailed lineshape analysis, the fractions of corner-bridging (CBF) and non-bridging fluoride (NBF) species were extracted. With increasing LiF (or NaF) content, the fraction of NBF increases significantly, producing an increased spectral contribution of the low-frequency lineshape components. 19F{7Li} rotational echo double resonance (REDOR) experiments reveal that this part of the MAS-NMR lineshape interacts most closely with the 7Li nuclei. The compositional dependence of the NBF fractions is discussed in the context of various scenarios, describing the transformation of CBF units into NBF units, and affecting the average coordination number of the Zr ions. The results indicate that the evolution of the NBF fraction cannot be described by a single scenario over the entire composition range.

[Diagnosis and therapy of cubital tunnel syndrome--state of the art]

The cubital tunnel syndrome is one of the most widespread compression syndromes of a peripheral nerve. In German-speaking countries it is known as the sulcus ulnaris syndrome (retrocondylar groove syndrome), which is anatomically incorrect. The cubital tunnel consists of the retrocondylar groove, the cubital tunnel retinaculum (Lig. arcuatum or Osborne band), the humeroulnar arcade and the deep flexor/pronator aponeurosis. According to Sunderland it can be divided into a primary form (including the ulnar luxation and the epitrocheoanconaeus muscle) and a secondary form caused by deformation or other processes of the elbow joint. The diagnosis has to be confirmed by a thorough clinical examination and nerve conduction studies. Neurosonography and MRI are becoming more and more important with improving resolution and enable the direct identification of morphological changes. Differential diagnosis is essential in atypical cases, especially C8 syndrome and pressure palsy. Double crush (double compression syndrome) may occur. Operative treatment is more effective than conservative treatment, which consists primarily of the prevention of exposure to external noxes. According to actual randomised controlled studies the therapy of choice of the primary form in most cases is the simple in situ decompression of the ulnar nerve in the cubital tunnel. This has to be extended at least up to 5-6 cm distally of the medial epicondyle and can be performed in the open or endoscopic technique, both under local anesthesia. Simple decompression is also the therapy of choice in uncomplicated ulnar luxation and in most post-traumatic cases and other secondary forms. In cases of severe bony or tissue changes of the elbow (especially cubitus valgus) the volar transposition of the ulnar nerve may be indicated. This can be performed in a subcutaneous or submuscular technique. Risks of transposition are impairment of perfusion and, above all, kinking caused by insufficient proximal or distal mobilisation of the nerve has to be avoided. In these cases revision surgery is necessary. The epicondylectomy is not common in our country. Recurrences may occur.

[Conception and evaluation of a group therapy intervention for patients with chronic pain disorders and applications for early retirement pensions]

OBJECTIVE

Patients with chronic pain disorder are generally thought to be difficult to treat in psychosomatic rehabilitation. On average, their disorders tend to take a more chronic course than those of other patients, and they develop a higher rate of additional socio-medical problems, all of which increase the probability of therapy failure. Most of the time, such failures are attributed solely to the desire for early retirement and disability pensions, that is, a characteristic of the patient. However, a lack of specific therapeutic offers for patients with predominant psycho-social problems has also to be considered. The project described was designed to evaluate a newly developed socio-medical therapy module. This module aimed at bringing more transparency to the process of assessing occupational capabilities and work performance, thus improving the patients' motivation to participate in the rehabilitation program as well as the overall therapy outcome.

METHODS

The project was implemented as a controlled, prospective evaluation study. A quasi-experimental 3-factorial design was employed, including two group factors (factor 1: socio-medical intervention [EG 1] vs. relaxation therapy module [EG 2]; factor 2: current application for premature pension vs. none; factor 3: repeated measurements [admission to inpatient therapy, discharge from the clinic, 6-months follow-up]). The treatment conditions for the experimental groups were realized according to an ABBA-scheme. Patients in both treatment conditions took part in pain disorder-specific coping groups and were also included in the regular inpatient treatment. At all three points of measurement, socio-demographic, socio-medical, symptomatic and motivational patient characteristics were obtained as dependent variables by use of well-established standardized patient surveys. In total, 206 patients suffering from a chronic pain disorder took part in the study (n [EG1]=100; n [EG2]=106). Both treatment groups were considered equal regarding relevant sample characteristics.

RESULTS

The socio-medical intervention was equally well accepted by all patients. Patients of the first experimental group turned out to be better informed about socio-medical issues than members of the second experimental group. The rehabilitation treatment program as a whole was--independently of treatment group affiliation--highly effective. Despite contrary expectations, the socio-medical intervention did not have an additional (differential) therapeutic effect on the patients at all points of measurement, not even on those participants currently applying for retirement pensions. Also, there were no significant differences between the treatment groups regarding the days of sick leave within six months after discharge from inpatient rehabilitation.

CONCLUSIONS

The original and possibly too ambitious goal of the project, namely to increase the rehabilitation success for patients with pain disorder and current pension applications by means of the therapeutic module labeled "social medicine", was not achieved. Nevertheless it is to be noted that this module was well received by the patients. Moreover, the authors consider it to be of high value in itself that this therapeutic module helps patients to become better informed.

Diagnostik und Therapie des Karpaltunnelsyndroms

Evidence-based supradisciplinary guideline that deals with the epidemiology, pathogenesis, symptoms, clinical and electrophysiological diagnosis, supplementary imaging investigations, differential diagnosis, conservative and surgical treatments, prognosis and course along with complications and revision surgery. The recommendations on investigation and treatment are based on a comprehensive literature search with critical evaluation and two consensus methods (expert group and Delphi technique) within the participating specialist societies. Besides this long version, a short version and a patient version can be viewed through the AWMF platform. The development of the guideline and the methodological foundations are documented in a method report. MAIN STATEMENTS: Apart from an accurate history and clinical neurological examination (including clinical tests), electrophysiological investigations (distal motor latency and sensory neurography) are particularly important. Radiography, MRI, high-resolution ultrasonography can be regarded as optional supplementary investigations. Among conservative treatment methods, treatment with a nocturnal splint and local infiltration of a corticosteroid preparation are effective. Oral steroids, splinting and ultrasound showed only short-term benefit. Surgical treatment is clearly superior to all other methods. Open and endoscopic procedures (when the endoscopic surgeon has sufficient experience) are equivalent. A routine epineurotomy and interfascicular neurolysis cannot be recommended. Early functional treatment postoperatively is important.

[Effects of therapy goal oriented cognitive behavioural aftercare measures on therapy transfer following inpatient psychosomatic rehabilitation]

OBJECTIVE

After discharge from inpatient psychosomatic rehabilitation patients often face problems to transfer and stabilize the modifications they have achieved in the clinic. Using targeted outpatient aftercare interventions up to eight weeks after discharge from the inpatient programme we tried to support this transfer, thus enhancing treatment effectiveness.

METHOD

The evaluation was carried out as a field experiment. Patients were matched into pairs and then allocated randomly to either a control or an experimental condition. The experimental group, which had participated in specific aftercare measures after inpatient therapy, was compared to the control group at "discharge from clinic" and "twelve weeks post-discharge" relative to a number of variables relevant in therapy outcome.

RESULTS

Twelve weeks post-discharge patients who had participated in aftercare measures show significantly better progress relative to their physical and psychological complaints than patients in the control group. Also, they are more capable of coping with psychosocial demands of their everyday life. They experience better control of their symptoms and they are more successful in attaining the goals they have set for themselves for the time after discharge.

CONCLUSIONS

The findings show that supplementing psychosomatic inpatient rehabilitation with specific aftercare measures will lead to better transfer and to increased effectiveness of psychosomatic rehabilitation. Also on account of our results, outpatient rehab aftercare programmes have in the meantime become a regular component of inpatient psychosomatic rehabilitation in Germany.