The angular course of the median nerve in the distal forearm and its anatomical importance in preventing nerve injury in a modern era of carpal tunnel release

Prevalence, variants, and morphometrics of Palmaris Longus tendon: a magnetic resonance imaging study

PURPOSE

The palmaris longus (PL) tendon present a high degree of variations; the commonest is its absence which could reach more than 40% in some populations. The PL tendon is highly relevant in hand reconstructive surgery; however, MRI variations of PL tendon have been exceptionally reported. To this, this study investigated PL tendon variations using MRI in a Lebanese population.

METHODS

This is a retrospective study of distal forearm MRI examinations to evaluate the presence, anatomical variations and morphometric of PL tendon. The outcomes were set as overall frequency, gender-based and side-base frequencies, correlations between prevalence and gender/side, morphological variants, thickness, and width of PL tendon.

RESULTS

The sample comprised 335 patients including a total of 339 MRI scans. The PL was present in 221 wrists (65.2%), and bilaterally in only one (25%) out of the 4 bilateral cases. All PL were located using the Axial T1 views. Univariate and multivariate analyses showed no correlation with side, gender, or Tesla power. The only morphological variation was a reversed PL in 2 cases (0.6%). The mean width was 4.24 ± 1.2 mm. The mean thickness was 2.75 ± 0.6 mm.

CONCLUSION

As far as we know, this is the first study to report the total array of variations of PL tendon using MRI, and its prevalence in a Lebanese population. The mean width of PL tendon calculated with high quality MR imaging was found to be similar to that reported by cadaveric studies.

Epidemiological characteristics of surgically treated civilian traumatic brachial plexus injuries in Serbia

BACKGROUND

Traumatic brachial plexus injuries are generally severe, and in many cases associated with surrounding tissue injuries, which makes them hard to diagnose at the right time. This paper presents etiological and epidemiological characteristics of surgically treated civilian traumatic brachial plexus injuries.

METHODS

This retrospective study included 68 patients, operated due to the traumatic brachial plexus injuries at Clinic for Neurosurgery, Clinical Center of Serbia, during the 11-year period.

RESULTS

The vast majority of injured patients were men in full working maturity. In our study, there were seven different etiological factors. The road traffic accidents were the most common-41 (60.3%), while the motorcycle accidents were the most dominant subtype (53.7%) of all road traffic accidents, and also representing 32.4% of all causes of trauma. Supraclavicular elements of the brachial plexus were injured in more than 80% of patients. A total of 49 (72.1%) patients from our study had one or more associated injuries. The most common associated injuries were bone fractures, brain contusions, and vascular injuries.

CONCLUSION

Although rare, non-war-related severe brachial plexus injuries represent a group of patients carrying high risk of insufficient functional recovery regardless of treatment modality, or surgical technique. Epidemiological and etiological data are therefore very important to identify the groups in risk and to induce preventive actions aimed at these patients.

Safety Window for the Volar Needle Approach for Examination of the Pronator Quadratus Using Ultrasonography

OBJECTIVES

To investigate pronator quadratus (PQ) anatomy and determine the proper volar needle insertion point based on landmarks, the tip of the ulnar styloid (an imaginary vertical line passing the tip of the ulnar styloid process [U line]), and the ulnar margin of the palmaris longus tendon (uPL) using ultrasonography.

DESIGN

Descriptive study.

SETTING

Department of physical medicine and rehabilitation.

PARTICIPANTS

Participants between 20 and 60 years without any diseases. (N=25; 13 men, 12 women; 50 forearms).

INTERVENTIONS

Ultrasonography.

MAIN OUTCOME MEASURES

The proximal and distal volar surface points of origin, the proximal and distal insertion sites, and the midpoint of the PQ (PQ_M) were determined. The distance of each of the PQ surface indices from the U line was measured, and the probe was positioned at the level of PQ_M parallel to the U line. The relative distances from the vertical surface points of the median nerve and ulnar artery to the uPL were measured.

RESULTS

The mean age and body mass index were 32.7±10.4 years and 21.98±2.83kg/m². The PQ_M was located at a mean distance of 2.63±0.35cm proximal from the U line (men 2.79±0.37cm and women 2.45±0.21cm; P<.05). The mean safety window for the volar approach was 0.72±1.8cm toward the radial side and 1.51±0.30cm toward the ulnar side from the uPL. The PQ was at a mean depth of 1.30±0.19cm from the skin and had a mean thickness of 1.19±0.24cm at the level of PQ_M. The distance between the U line and the proximal edge of the PQ, as well as the PQ thickness, was greater in men than in women.

CONCLUSIONS

The volar approach for needle electromyographic examination of the PQ can be performed precisely and safely.