Transfer of the flexor carpi radialis to the abductor pollicis brevis tendon for the restoration of tip-pinch in severe carpal tunnel syndrome

Morphology and innervation of brachioradialis and flexor carpi radialis and their utility in tendon transfer surgeries: A Cadaveric Study

INTRODUCTION

The Brachioradialis (BR) muscle flap is easy to harvest, provides a stable coverage to the cubital fossa as it is well vascularized. The BR andflexor carpi radialis (FCR) tendons are utilized in tendon transfer to restore the normal hand function. Therefore, the present study describes the morphology of the muscle bellies and the tendons of BR and FCR along with their pattern of innervation.

MATERIALS AND METHODS

The study was carried out on 27 upper limbs of formalin-fixed, adult human cadavers. Length and width of the bellies of BR and FCR were measured. The number of motor branches and their distances from the bi-epicondylar line was measured.

RESULTS

The mean lengths of BR and FCR bellies were 21.22±2.18cm and 16.15±2.39cm, and the lengths of their tendons were, 12.67±1.13cm and 12.48±1.72cm respectively. BR received a single motor branch in 19 upper limbs. However, FCR received single motor branch in 25 limbs as a common trunk. One upper limb received three motor branches to BR, and two upper limbs received two motor branches to FCR. The most proximal and distal branches to the BR were ranged between 6.3-2.2cm proximal to the bi-epicondylar line. Those to the FCR were ranged between 3.5-6.9cm distal to the bi-epicondylar line.

CONCLUSION

The motor branches to the BR and FCR are variable in their origin, and the knowledge of such variations is essential for identifying them while performing selective neurotomy surgeries.

Motor Examination in the Diagnosis of Carpal Tunnel Syndrome

The relative importance and use of motor evaluation to diagnose carpal tunnel syndrome (CTS) is not clear. Because the ulnar nerve is not affected in CTS, we evaluated comparing the strength of the median-nerve innervated muscles to the ulnar innervated muscles in the same patient, through manual muscle testing (MMT) and a handheld dynamometer. Our purpose was to evaluate whether this method, which takes into account patient-dependent factors that would affect both groups of muscles equally, can provide better assessment of CTS. A retrospective case-control review of MMT and dynamometer-measured strength for CTS was performed. The study was performed retrospectively but prior to surgery or other treatment. There were 28 cases (CTS) and 14 controls (without CTS). Positive nerve conduction tests defined cases. MMT of the thenar musculature was found to be unreliable as a test for CTS. Comparisons to ulnar nerve innervated muscle strength did not improve sensitivity or specificity of the MMT examination. Use of the dynamometer improved sensitivity and specificity of motor testing in CTS over MMT. Motor evaluation is important for the diagnosis of CTS, but further study is warranted, specifically to define the method of motor evaluation and delineate the subgroup of patients (predominantly thenar motor presentation) that would benefit most from motor testing and motor-focused treatment.

A morphometric study on flexor carpi radialis muscle of the forearm: A cadaveric study

BACKGROUND

Flexor carpi radialis (FCR) is frequently used in reconstruction procedures involving the hand and wrist regions. Despite having tremendous clinical significance, very few studies have been conducted on the heterogeneity of the FCR. Its surgical importance in grafting techniques and tendon transfers prompted us to study the morphometry of FCR.

MATERIALS AND METHODS

In this study, we used 37 upper limbs (25 right and 12 left sides) of formalin embalmed cadavers. FCR was neatly dissected in all upper limbs to measure its total length, muscle belly length, tendon length, width of muscle belly at proximal and distal ends, width of tendon at proximal and distal ends.

RESULTS

Average total length of the muscle, muscle belly length, tendon length, width of muscle belly at the proximal end, width of muscle belly at the distal end, width of tendon at the proximal end, width of tendon at the distal end were 27.1 ± 2.13, 12.38 ± 2.23, 14.99 ± 2.36, 1.99 ± 0.72, 1.59 ± 0.48, 1.59 ± 0.48 and 0.42 ± 0.12 cm, respectively. Ratio of mean muscle length and tendon length, ratio of mean tendon length and total length were found to be 0.45 ± 0.07 and 0.55 ± 0.07, respectively. No noted variations were observed in the proximal and distal attachments of the FCR muscle.

CONCLUSION

Morphometric data of FCR reported increases the existing knowledge on the heterogeneity of FCR morphology, and further forms an anatomic basis while designing/elevating the graft in certain surgical procedures in hand and wrist regions.

Scaffolds for hand tissue engineering: the importance of surface topography

Tissue engineering is believed to have great potential for the reconstruction of the hand after trauma, congenital absence and tumours. Due to the presence of multiple distinct tissue types, which together function in a precisely orchestrated fashion, the hand counts among the most complex structures to regenerate. As yet the achievements have been limited. More recently, the focus has shifted towards scaffolds, which provide a three-dimensional framework to mimic the natural extracellular environment for specific cell types. In particular their surface structures (or topographies) have become a key research focus to enhance tissue-specific cell attachment and growth into fully functioning units. This article reviews the current understanding in hand tissue engineering before focusing on the potential for scaffold topographical features on micro- and nanometre scales to achieve better functional regeneration of individual and composite tissues.

Simultaneous modified Camitz opponensplasty using a pulley at the radial side of the flexor retinaculum in severe carpal tunnel syndrome

Camitz opponensplasty using the palmaris longus has been used in patients undergoing open carpal tunnel release. It is considered to have several advantages over other opponensplasty techniques, but it provides weak flexion and pronation, which are prerequisites for opposition. To address this shortcoming, we have used a modified Camitz procedure with a pulley at the radial side of the dissected flexor retinaculum and have assessed the results in comparison with the conventional Camitz procedure. Both procedures provided significant improvements in palmar abduction and Disabilities of the Arm, Shoulder, and Hand and Kapandji scores at 3 months post-operatively, but patients who underwent the modified Camitz procedure showed better improvement in pulp pinch, palmar abduction, and thumb pronation.