Anterior Interosseous Syndrome Research Articles

Pathophysiology and treatment of spontaneous anterior interosseous nerve palsy and spontaneous posterior interosseous nerve palsy

Spontaneous anterior or posterior interosseous nerve palsy is usually treated as a part of neuralgic amyotrophy. However, recent studies have shown that many of these cases involved fascicular constriction in the affected nerves, and interfascicular neurolysis may be a better option than conservative treatment in cases that do not show spontaneous recovery within several months. Here, we review recent studies on these palsies.

Clinical Case of the Korean Medical Treatment for the Patient with Anterior Interosseous Nerve Syndrome

The purpose of this study is to suggest a possibility of the Korean medical treatment in patient with anterior interoseous nerve entrapment syndrome. The patient treated with acupunture, herbal medicine and Needle-embedding Therapy from April 19th to May 15th. We measured Visual Analotgue Scale(VAS), and Observed the change in body tempreture using Digital Infrared Thermal Imaging(DITI). After received Korean medical treatment, the patient showed improvement in muscle strength, sensation, VAS, temperature differential. Therefore we can consider Korean medical treatment before operation in interosseous nerve syndrome.

Literature review about anterior interosseous nerve (AIN) syndrome illustrated by two cases

Literature review about anterior interosseous nerve (AIN) syndrome illustrated by two cases

Décompression du nerf médian assistée par endoscopie dans le syndrome pronateur et le syndrome de Kiloh-Nevin : technique chirurgicale

State of the artThe proximal median nerve compression syndrome includes the pronator teres and the Kiloh-Nevin syndrome. This article presents a new surgical technique of endoscopic assisted median nerve decompression. Material and surgical techniqueEndoscopic scissor decompression of the median nerve is always performed under plexus anaesthesia. It includes 6 key steps documented in this article. We review the indications and limitations of the surgical technique. ResultsSince 2011, three clinical series have highlighted the advantages of this technique. Functional and subjective results are discussed. We also review the limitations of the technique and its potential for future development. ConclusionAlthough clinical results after endoscopic assisted decompression of the median nerve appear excellent they still need to be compared with conventional techniques. Clinical studies are likely to develop primarily due to the mini-invasive nature of this new surgical technique.

Early Functional Recovery of Elbow Flexion and Supination Following Median and/or Ulnar Nerve Fascicle Transfer in Upper Neonatal Brachial Plexus Palsy

Nerve transfers using ulnar and/or median nerve fascicles to restore elbow flexion have been widely used following traumatic brachial plexus injury, but their utility following neonatal brachial plexus palsy remains unclear. The present multicenter study tested the hypothesis that these transfers can restore elbow flexion and supination in infants with neonatal brachial plexus palsy. We retrospectively reviewed the cases of thirty-one patients at three institutions who had undergone ulnar and/or median nerve fascicle transfer to the biceps and/or brachialis branches of the musculocutaneous nerve after neonatal brachial plexus palsy. The primary outcome measures were postoperative elbow flexion and supination as measured with the Active Movement Scale (AMS). Patients were followed for at least eighteen months postoperatively unless they obtained full elbow flexion or supination (AMS = 7) prior to eighteen months of follow-up. Twenty-seven (87%) of the thirty-one patients obtained functional elbow flexion (AMS ≥ 6), and twenty-four (77%) obtained full recovery of elbow flexion against gravity (AMS = 7). Of the twenty-four patients for whom recovery of supination was recorded, five (21%) obtained functional recovery. Combined ulnar and median nerve fascicle transfers were performed in five patients and resulted in full recovery of elbow flexion against gravity and supination of AMS ≥ 5 for all five. Single-fascicle transfer was performed in twenty-six patients and resulted in functional flexion in 85% (twenty-two of twenty-six) and functional supination in 15% (three of twenty). Patients with nerve root avulsion were treated at a younger age (p < 0.01), had poorer preoperative elbow flexion (p < 0.01), and recovered greater supination (p < 0.01) compared with patients with dissociative recovery. Younger patients (p < 0.01) and patients with C5-C6 avulsion (p < 0.02) recovered the greatest supination. One patient sustained a transient anterior interosseous nerve palsy after median nerve fascicle transfer. Ulnar and/or median nerve fascicle transfers were able to effectively restore functional elbow flexion in patients with nerve root avulsion, dissociative recovery, or late presentation following neonatal brachial plexus palsy. Recovery of supination was less, with greater success noted in younger patients with nerve root avulsion.

Anterior interosseous nerve syndrome

Objective:We sought to determine lesion sites and spatial lesion patterns in spontaneous anterior interosseous nerve syndrome (AINS) with high-resolution magnetic resonance neurography (MRN).Methods:In 20 patients with AINS and 20 age- and sex-matched controls, MRN of median nerve fascicles was performed at 3T with large longitudinal anatomical coverage (upper arm/elbow/forearm): 135 contiguous axial slices (T2-weighted: echo time/repetition time 52/7,020 ms, time of acquisition: 15 minutes 48 seconds, in-plane resolution: 0.25 × 0.25 mm). Lesion classification was performed by visual inspection and by quantitative analysis of normalized T2 signal after segmentation of median nerve voxels.Results:In all patients and no controls, T2 lesions of individual fascicles were observed within upper arm median nerve trunk and strictly followed a somatotopic/internal topography: affected were those motor fascicles that will form the anterior interosseous nerve further distally while other fascicles were spared. Predominant lesion focus was at a mean distance of 14.6 ± 5.4 cm proximal to the humeroradial joint. Discriminative power of quantitative T2 signal analysis and of qualitative lesion rating was high, with 100% sensitivity and 100% specificity (p < 0.0001). Fascicular T2 lesion patterns were rated as multifocal (n = 17), monofocal (n = 2), or indeterminate (n = 1) by 2 independent observers with strong agreement (kappa = 0.83).Conclusion:It has been difficult to prove the existence of fascicular/partial nerve lesions in spontaneous neuropathies using clinical and electrophysiologic findings. With MRN, fascicular lesions with strict somatotopic organization were observed in upper arm median nerve trunks of patients with AINS. Our data strongly support that AINS in the majority of cases is not a surgically treatable entrapment neuropathy but a multifocal mononeuropathy selectively involving, within the main trunk of the median nerve, the motor fascicles that continue distally to form the anterior interosseous nerve.

Early treatment of anterior interosseous nerve palsy with hourglass-like fascicular constrictions by interfascicular neurolysis due to early diagnosis using ultrasonography: A case report

Early treatment of anterior interosseous nerve palsy with hourglass-like fascicular constrictions by interfascicular neurolysis due to early diagnosis using ultrasonography: A case report

A CASE REPORT OF A GIANT FOREARM LIPOMA CAUSING ANTERIOR INTEROSSEOUS NERVE PALSY AFTER FRACTURE OF THE DISTAL RADIUS

To the best of our knowledge, there are no previous reports on anterior interosseous nerve palsy (AINP) caused by a soft tissue tumor after fracture of the distal radius. We treated a case of giant forearm lipoma that caused AINP one day after internal fixation of a distal radius fracture.

측와위로 시행한 견관절 관절경 후에 동시에 발생한 전방 및 후방 골간 신경 증후군 - 증례보고 -

We report a case of simultaneous anterior and posterior interosseous nerve syndrome in association with shoulder arthroscopy. Shoulder arthroscopy was performed in a 45-year-old male patient with left shoulder instability. In the right lateral decubitus position, under general anesthesia, traction was applied with elbow extension for 2 hours. One week after surgery, the patient revisited the clinic for weakness of the flexor of the thumb, index finger, and extensor of the fingers. Recovery was not achieved after four months of observation. Therefore, nerve exploration was performed in the anterior and posterior interosseous nerve and hourglass-like fascicular constriction was detected in the posterior interosseous nerve. The area of constriction was removed and epineural neurorrhaphy was performed. Three months after exploration, the extension function of the fingers was recovered. Recovery was achieved gradually, and, five months after nerve exploration, the symptoms were completely recovered. Simultaneous anterior and posterior interosseous nerve syndrome following shoulder arthroscopy is rare. However, it could occur due to the traction and position of the patient. Thus, the operator should be careful of traction and position of the patient.

Should You Explore the Brachial Artery in Children Who Have a Perfused Hand but No Palpable Radial Pulse After Sustaining a Supracondylar Humeral Fracture?

The articles by Weller et al. and Scannell et al. add another seventy patients to the literature describing good outcomes for closely observed patients who have a perfused hand but no palpable radial pulse after undergoing closed reduction and percutaneous pinning of a supracondylar humeral fracture. Weller et al. described a high-volume experience at their institution, where the approach is to observe most patients who have a perfused hand but no palpable pulse in association with a supracondylar humeral fracture (this approach varies according to the preference of the attending surgeon, however, so some of these fractures were explored during the time course of the study). If a palpable radial pulse does not return following closed reduction and percutaneous pinning, the rationale for exploration of the brachial artery in their center hinges on the outcome of Doppler assessment of the radial artery; that is, vascular consultation and exploration for those without a Doppler signal, and observation for those who have a Doppler signal. Their paper has the limitations of a retrospective study, and they do not have very long follow-up on the patients. They do report on the cases of two patients that provide valuable teaching points. One patient, who had improved vascular status after undergoing closed reduction and percutaneous pinning, had subsequent deterioration during observation and was returned to the operating room for exploration after developing a cool, poorly perfused hand. Another patient with a perfused hand but no palpable radial pulse developed an ischemic contracture of the forearm despite having a benign and routine postoperative hospital course. This patient had no palpable pulse before or after closed reduction and percutaneous pinning but had a Doppler signal at the radial artery before and after and had a palpable pulse prior to discharge from the hospital. After discharge, the patient …

Anterior Interosseous Nerve Palsy after Supracondylar Fracture of Humerus in Adult. Case report

We present a case of anterior interosseous nerve palsy after a supracondylar fracture of the humerus in a 24-year-old woman. The patient was diagnosed and treated in two hospitals where the impairment of function of the hand indicating nerve damage was not noticed during a standard examination. An open reduction of the fracture with internal fixation using LCP plates and additional screws was performed, ultimately producing a good therapeutic outcome. Anterior interosseous nerve palsy was detected after 14 days during the first follow-up visit. The decision was made to institute conservative treatment. Full functional recovery was achieved after approximately 8 months. We believe that injuries of this type are more common but can be easily overlooked in the course of an imprecise physical examination. The Introduction of improved algorithms for the clinical examination of patients with similar fractures should be considered for the patient's good and on account of possible legal aspects of a failure to establish a correct diagnosis.

Anterior Interosseous Nerve Palsy as a Complication of Proximal Humerus Fracture

Anterior interosseous nerve palsy subsequent to proximal humerus fracture is rare compared with an axillary nerve injury. This article presents a case of anterior interosseous nerve palsy secondary to such a fracture in an 87-year-old woman after a simple fall onto her outstretched hand. The patient had no sensory involvement but was unable to form an O with her thumb and index finger. She had a positive pointing index test on attempting to clasp her hand. The fracture and nerve palsy were treated conservatively. At 3-month follow-up, the patient had partial recovery; therefore, electromyography was not performed. By 6 months, she had complete recovery of anterior interosseous nerve palsy. This case highlights the possibility of sustaining anterior interosseous nerve palsy with proximal humerus fracture with a classical clinical presentation. Because most nerve lesions after proximal humerus fracture are neurapraxia, symptoms usually resolve either partially or completely after a few months. It is recommended that cases with proximal humerus fracture be evaluated carefully for median nerve and axillary nerve injury. In addition, it is recommended to perform electromyography if no signs of recovery are evident at 3-month follow-up.

English

BACKGROUND: Accessory head of Flexor pollicis longus in the forearm is one of the factors for causing anterior interosseous nerve syndrome. The objectives were to study the incidence, morphology of accessory head of flexor pollicis longus and its relation with median nerve and anterior interosseous nerve. METHODS: The present study was observational and descriptive type. A total of 60 upper limbs from 30 cadavers were dissected in the Department of Anatomy. The accessory head of flexor pollicis longus muscle was identified and its relation with median and anterior interosseous nerve was observed. The shape, origin and insertion of accessory head of flexor pollicis longus were noted. The length and width of the muscle belly and tendon were measured with digital vernier caliper. The findings were compared with that of previous studies. RESULTS: The accessory head of flexor pollicis longus was present in 13(43.3%) cadavers. The shape of muscle was fusiform in 84.61% and slender in 19.38%.Commonest site of origin was coronoid process of ulna (53.33%)., from the medial epicondyle 33.33% and 6.66% each form tendon of brachialis and deep head of pronator teres respectively. The average length and width of muscle belly were 93.48 ± 1.76mm and 7.03 ± 1.43 respectively. The tendon length and width were 20 ± 8.09mm and 0.55 ± 0.23mm. The median nerve was running anteriorly and the anterior interosseous nerve laterally to the muscle belly in all the cases. CONCLUSION: The presence of accessory head of flexor pollicis longus can be an important factor in anterior interosseous nerve syndrome, pronator teres syndrome. The results obtained in the present study would be useful for both physicians and surgeons to know the cause and therefore an appropriate management of the clinical syndromes.

The anatomical basis for anterior interosseous nerve palsy secondary to supracondylar humerus fractures in children

Various studies have found that 6.6 to 31% of supracondylar elbow fractures in children have nerve-related complications. One-third of these are cases of anterior interosseous nerve (AIN) palsy that usually result in a deficit of active thumb and index flexion. The goal of this cadaver study was to describe the course of the AIN to achieve a better understanding of how it may get injured. On 35 cadaver specimens, the median nerve and its collateral branches destined to muscles were dissected at the elbow and forearm levels. The distance at which the various branches arose was measured relative to the humeral intercondylar line. Interfascicular dissection of the AIN was used to map its distribution within the median nerve. The AIN arises at an average of 45 mm from the humeral intercondylar line. Before emerging from the median nerve, the AIN fascicles were always found in the dorsal part of the median nerve. After emerging, the AIN was divided into two zones. Zone 1 was the transitional portion from its exit point until its entrance into the interosseous space, where it changes direction. Zone 2 was the interosseous portion between the radius and ulna that comes into contact with the anterior interosseous membrane to which it is attached over its entire length until it ends in the pronator quadratus (PQ) muscle. The muscle branches of the AIN destined for the flexor pollicis longus (FPL) and flexor digitorum profundus (FDP) muscles mostly originated in Zone 1, which is the transitional portion between the median nerve and the fixed Zone 2. The branches destined to the pronator teres (PT) and flexor carpi radialis (FCR) originating from the median nerve are more proximal and superficial. The injury mechanisms leading to selective AIN palsy secondary to supracondylar elbow fracture in children are probably the result of two factors: direct contusion of the posterior aspect of the median nerve, and thereby the AIN fascicles, by the proximal fragment; stretching of AIN in Zone 1, which has less ability to withstand stretching than the median nerve and its other branches because the AIN is fixed in Zone 2. Details about the origin and course of the AIN can explain the high percentage of AIN palsy in supracondylar elbow fractures in children. Level IV. Anatomic study.

Gantzer muscles and their applied aspects: an exceptional finding

Anatomical variations are typically more common in the extensor compartment of the forearm, but uncommon in the flexor compartment. The presence of such anatomical anomalies is not usually noticed until the normal functions of an individual become hindered, or when these anomalies become a surgical problem. During routine dissection curriculum, we encountered a rare finding of bilateral Gantzer muscles in a cadaver. We describe the relationship between the Gantzer muscle and anterior interosseous nerve syndrome.

Surgical treatment of spontaneous anterior interosseous nerve palsy: A comparison between minimal incision surgery and wide incision surgery

Recent reports have suggested that fascicular constriction located proximal to the elbow may be the primary aetiology of spontaneous anterior interosseous nerve palsy (sAINP), and recommended interfascicular neurolysis ranging from the proximal forearm to distal upper arm (wide incision surgery: WIS) for its treatment. On the basis of these reports, it was hypothesised that, if the aetiology of sAINP was fascicular constriction, neurolysis limited proximal to the elbow (minimal incision surgery: MIS) should have similar results to those of WIS. Twenty-five surgically treated sAINP cases were retrospectively evaluated. The mean age of onset was 42.8 years, the mean preoperative period was 5.3 months, and mean follow-up period after operation was 31 months. Eleven patients underwent MIS, while 14 underwent WIS according to the patient's intention (intention-to-treat). Twenty-one patients had fascicular constriction, and no entrapment neuropathy was seen in this series. At the latest follow-up, 82% of the patients had British Medical Research Council grade of ≥4 in flexor-pollicis-longus, while 80% had grade of ≥4 in flexor-digitorum-profundus-of-the-index-finger. There were no significant differences between the results of either group. These result suggested that the aetiology of sAINP may not be external compression, but fascicular constriction, and MIS may be its favourable surgical treatment.

Pronator Syndrome and Anterior Interosseous Nerve Syndrome

Dysfunction of the median nerve at the elbow or proximal forearm can characterize two distinct clinical entities: pronator syndrome (PS) or anterior interosseous nerve (AIN) syndrome. PS is characterized by vague volar forearm pain, with median nerve paresthesias and minimal motor findings. AIN syndrome is a pure motor palsy of any or all of the muscles innervated by that nerve: the flexor pollicis longus, the flexor digitorum profundus of the index and middle fingers, and the pronator quadratus. The sites of anatomic compression are essentially the same for both disorders. Typically, the findings of electrodiagnostic studies are normal in patients with PS and abnormal in those with AIN syndrome. PS is a controversial diagnosis and is typically treated nonsurgically. AIN syndrome is increasingly thought to be neuritis and it often resolves spontaneously following prolonged observation. Surgical indications for nerve decompression include persistent symptoms for >6 months in patients with PS or for a minimum of 12 months with no signs of motor improvement in those with AIN syndrome.

Spontaneous anterior interosseous nerve syndrome: clinical analysis of eleven surgical cases

The aetiology of anterior interosseous nerve (AIN) syndrome and an optimal treatment strategy remain controversial. Eleven patients with spontaneous AIN syndrome, who were treated by surgical exploration, were reviewed at a mean of 32.5 months after the operation. Eight men and three women were included in the study. None of the patients had a history of trauma and there was no evidence of a neuropathy other than AIN syndrome. Six patients showed complete paralysis of the flexor pollicis longus (FPL) and the flexor digitorum profundus of the index finger (FDS1). Five patients had incomplete paralysis, with isolated lesions of the FPL in two and the FDP1 in three. Surgery was performed 7.8 months after the onset of paralysis. The most common structure of nerve compression was a fibrous band of the flexor digitorum sublimis muscle. However, no definitive compression site or anatomic abnormality could be found in four patients. Ten of the 11 patients had recovered muscle strength above grade 4 within 12 months of the operation. Good results were obtained in 10 patients and fair in only one at final assessment. Four patients (one man and three women) raised cosmetic concerns due to excessive scar formation on the upper forearm. Surgical exploration is recommended only in cases where AIN syndrome is apparent, no other neuronal lesions are apparent, and where there was no recovery after 6 months of conservative treatment. Careful preoperative examination is essential to avoid misdiagnosis and inappropriate operation, particularly in cases of incomplete AIN syndrome.

Compressions du nerf médian dans la région du coude et de la partie proximale de l’avant-bras. À propos d’une série de 35 cas consécutifs

Median nerve entrapment at the elbow and the proximal forearm represents 7 to 10 % of median nerve mononeuropathies. Literature distinguishes two distinct syndromes: the pronator syndrome and the anterior interosseous nerve syndrome. We report a retrospective series of 35 cases of proximal compression of the median nerve, including a previous study of 13 cases assessed in 2001. Thirty-four patients were operated on between 1994 and 2011. The series included 15 men and 19 women with a mean age of 57years. Subjective complaints were the main reason of consulting with or without a deficit. All but one benefited from a preoperative electrical study. Neurography showed abnormalities in 18 cases and myography in 30 cases. At least one site of compression was found at surgery. Thirty-one cases, including nine of the 13 cases previously evaluated in 2001, were assessed with a mean follow-up of 69months. Twenty-height considered them improved and all but one were objectively improved by surgery. The nine cases evaluated in 2001 had better results in 2011. Through this series and an exhaustive literature review, we concluded that there are no preoperative criteria that can differentiate a pronator teres syndrome from an anterior interosseous nerve syndrome. If no improvement occurs, surgical treatment should be proposed, one must then assess all potential sites of nerve entrapment. Patients must be informed that improvement can take several years.

PRESENCE OF TRIPLE GANTZER'S MUSCLE - A RARE ANATOMICAL VARIATION

AbstractAnomalous muscles usually do not result in adverse symptoms but are of academic interest. However, these muscles can create neurovascular compression at times. Muscle anomalies of the upper extremity are recognized causes of peripheral nerve disorder. Koloh-Nevin Syndrome (Anterior Interosseous Nerve Syndrome) caused by the compression neuropathy of the anterior interosseous nerve in the forearm is believed to occur because of its compression by the accessory heads of flexor pollics longus (FPLah) and flexor digitorum profundus (FDPah). The above two accessory muscles are also called Gantzer's muscle. During routine cadaveric dissection, we encountered multiple Gantzer's muscles in a 60 year-old- formalin embalmed male cadaver. Along with the usual FPLah and FDPah described by Gantzer, we too observed an accessory muscle in relation to the flexor digitorum superficialis (FDS). All the three anomalous muscles had a common origin from the under cover of the FDS fibers and by fibrous band above the insertion of brachialis. The presence of multiple additional muscles in the forearm flexor compartment is rare and clinically significant.