Torsional Anatomy of the Lower Limb: The Appearance of Anatomy in Hemispastic Position.

OBJECTIVE: The aim of the study was to determine whether there are relevant anatomical variations to the typical injection sites for antispasticity procedures in the lower limb. METHODS: Sonographic images were obtained at traditional injection locations for spasticity in the lower limb. Images were recorded in neutral and contracted postures. Doppler imaging was obtained for sites that contained vasculature. The images were analyzed, and schematics were created that highlighted relevant findings. RESULTS: The adductor longus in commonly used injection sites was close to vasculature making accidental injection of the latter a higher risk. The sciatic nerve was vulnerable to injections at the proximal biceps femoris injection side if injected too deeply. Hamstring injection sites can be adjusted to the midline to improve accuracy. The proximity of the tibial nerve to the flexor hallucis longus and the deep fibular nerve to the extensor hallucis longus puts these nerves at risk for accidental injection. DISCUSSION: Contracted posture results in altered positions of lower extremity muscles that could lead to inadvertent neurovascular injection or decreased efficacy with injections. Findings in this study may be helpful for planning and executing injections to reduce spasticity in the lower extremity. CONCLUSIONS: Sonographic imaging allows a better localization of muscles associated with spasticity and can instruct the clinician to alter usual injection pathways. This article documents visual evidence that previous assumptions for injection strategies require updating.

Procedure-Oriented Torsional Anatomy of the Hand for Spasticity Injection.

OBJECTIVES: To provide musculoskeletal ultrasound (MSKUS) images of hand anatomy in the position of hemiparetic flexion as a reference for spasticity injections. After a stroke, spasticity can result in anatomic distortion of the hand. Spasticity may require treatment with botulinum toxin or phenol injections. Anatomic distortion may decrease the accuracy of injections. Standard anatomic references are of limited utility because they are not in this spastic hemiparetic position. There presently is no anatomic reference in the literature for these spastic postures. This study is part three of a series examining torsional anatomy of the body. DESIGN: Ultrasound (US) images were obtained in a healthy subject. The muscles examined included the lumbricals and the flexor pollicis brevis. A marker dot was placed at each dorsal and palmar anatomic injection site for these muscles. The US probe was placed on these dots to obtain a cross-sectional view. A pair of US images was recorded with and without power Doppler imaging: the first in anatomic neutral and second in hemiparetic spastic positions. In addition, a video recording of the movement of the muscles during this rotation was made at each site. RESULTS: On the palmar view, the lumbricals rotated medially. On dorsal view, the lumbricals can be seen deep to the dorsal interossei muscles, with spastic position, and they become difficult to identify. The flexor pollicis brevis (FPB) muscle contracts with torsion, making abductor pollicis brevis (APB) predominately in view. DISCUSSION: The anatomic location of the lumbrical muscles makes them difficult to inject even with ultrasound guidance. However, recognizing the nearby digital vasculature allows for improved identification of the musculature for injection purposes. The FPB muscle also can be identified by its adjacent radial artery lateral to the flexor pollicus longus tendon. CONCLUSION: Normal anatomy of hand can become distorted in spastic hemiparesis. Diagnostic ultrasound is able to discern these anatomic locations if the sonographer is competent in recognizing the appearance of normal anatomy and is skilled in resolving the visual changes that occur in spastic hemiparesis. The authors hope this series of images will increase the accuracy, safety, and efficacy of spasticity injections in the hand.

Procedure Oriented Torsional Anatomy of the Forearm for Spasticity Injection.

UNLABELLED: : This is the second in a series of articles related to the concept of "torsional" anatomy. The objective of this article is to provide musculoskeletal ultrasound (MSKUS) anatomy of the forearm in the position of hemispastic flexion as a reference relevant to needle procedures. METHODS: The MSKUS images were obtained in a healthy human subject. Marker dots were placed over common injection sites in the forearm for spasticity. The MSKUS probe was centered over each dot to obtain a cross-sectional view. A pair of MSKUS images was recorded for each site: the first in anatomic neutral and second in hemiparetic spastic position. The images were compared side to side. In addition, a video recording was made at each site to track the movement of the muscles and nerves during internal rotation. RESULTS: The pronator teres (PT) rotated medially and the brachialis and biceps tendon rotated in view. In addition, the median nerve became more superficial. The flexor carpi radialis rotated medially and was replaced by PT and the median nerve. The flexor carpi ulnaris and flexor digitorum profundus rotated medially and were replaced by the flexor carpi radialis, PT and median nerve. The flexor digitorum superficialis was replaced by the brachioradialis, extensor carpi radialis brevis, and radial nerve. The brachioradialis was replaced by the extensor carpi radialis brevis and extensor digitorum communis. DISCUSSION: Intended muscle targets rotate out of view and injection range. These are replaced by other muscles and nerves that could inadvertently be injected. This potentially could result in both increased complications and decreased efficacy of the procedure. CONCLUSIONS: It is hoped that this series of images will increase the accuracy and safety of needle placement for spasticity injections in the forearm.

Procedure-oriented torsional anatomy of the proximal arm for spasticity injection.

UNLABELLED: This is the first in a series of papers related to the new concept of "torsional" anatomy. The objective of this article is to provide musculoskeletal ultrasound (MSKUS) anatomy of the upper arm in the position of hemispastic flexion as a reference relevant to needle procedures. METHODS: The MSKUS images were obtained in a healthy human subject. A pair of MSKUS images was recorded for each level: the first in anatomic neutral and second in hemispastic position. RESULTS: At the proximal 1/3 level of the upper arm, the pectoralis major rotated out of view. At the middle of the upper arm, the biceps rotated medially, and the brachialis rotated from far lateral to the middle of the screen. At the distal 1/3 level of the upper arm, the radial nerve rotated more anteriorly. At the distal 1/6 level of the upper arm, the biceps shifted and was replaced by the brachialis and brachioradialis. The radial nerve also rotated more anteriorly and superficially. DISCUSSION: With torsion, it is possible that intended muscle targets, such as the pectoralis, are missed, and unintended targets, such as the radial nerve, are accidentally injected in the upper arm. CONCLUSIONS: It is hoped that this series of images will increase the accuracy and safety of needle placement for spasticity and nerve block injections in the proximal upper arm.

Procedure-oriented sectional anatomy of the foot.

This is the seventh and last in a series of studies related to procedure-oriented joint anatomy. This article reviews the anatomy of the foot and its relationship to procedures in the clinical setting with or without ultrasound guidance. Anatomically correct axial schematics allow injections to be envisioned relative to clinically important anatomy for common forefoot procedures. Cross-sectional schematics for the ankle were drawn as they appear in imaging projections. The levels and planes of cross section were selected to highlight important anatomic landmarks for injection. It is hoped that these schematics allow for safer and more accurate needle procedures in the foot area.