Ultrasound Measurements of the First Extensor Compartment: Determining the Transection Limits for Ultra-minimally Invasive Release of De Quervain Tenosynovitis

Background: De Quervain syndrome is the second most common compressive tendinopathy. Although the length of the first extensor compartment (FEC) has been studied previously, there is no documented reported comparison study of short-axis and long-axis sonographic measurements. The thread technique, or Guo Technique, has been applied to carpal tunnel syndrome, trigger finger, and superficial peroneal compressive neuropathy. To perform this procedure, it is critically important to accurately identify the boundaries for transection. Methods: Twenty-one fresh frozen cadaver upper extremities were examined under ultrasound to determine the length of the extensor retinaculum (ER) over the FEC. Using the sonographic landmarks, the ERs were measured in short axis and long axis over their proximal to distal margins and from the distal margins to the distal edges of the radial styloids. These sonographic measurements were then compared with gross anatomical measurements. Results: The short-axis sonographic measurement of the ER on average was 22.53 mm (95% confidence interval [CI] = 20.79-24.05 mm). The long-axis sonographic measurement of the ER on average was 15.65 mm (95% CI = 13.70-17.78 mm). The average length of the ER by gross anatomical dissection was 22.40 mm (95% CI = 21.15-23.51 mm). Conclusions: The short axis is not significantly different from the gross anatomical measurement; however, the long axis is significantly lower than the gross anatomical measurement. The results support the idea that the short axis is more accurate than the long axis.

Ultrasound-Guided de Quervain's Tendon Release, Feasibility, and First Outcomes

Background de Quervain's syndrome is one of the main tendonitis of the wrist. The hypothesis of authors was that de Quervain's syndrome could be successfully treated with a specific ultrasound-guided percutaneous procedure, as it is for trigger finger. Surgical Technique Identification of the subcompartmentalization of the first extensor compartment was performed first, using the Hiranuma's classification, prior to the surgery. Then, we assessed precisely the positions of the sensory branches of the radial nerve and drew the landmarks. Through a continuous ultrasound in-plane control, we performed a percutaneous retrograde section of each part of the first compartment of the extensors, using a dedicated surgical blade. Methods In a cadaveric study, authors proposed to assess the feasibility and safety of a new and specific procedure and then assessed their first clinical cases. Fourteen specimen wrists were analyzed with ultrasound and the procedure was performed prior to an open control of the efficiency of the release, and safety for the superficial nerves. Then, we reported the results of the 22 first patients included in the clinical series. Results In a cadaver laboratory, authors were able to identify with ultrasound the type of first compartment septation (subcompartmentalization) in 13 cases (n = 14). The misidentification induced one incomplete release. No damages of the superficial radial nerve were observed despite close relationship. In the small series (n = 22), the duration of surgery was 8 minutes (range: 4–18 minutes). It was performed in office surgery and no morbidities were noticed. All patients improved, from quickDASH preoperative score of 59 (range: 28–71) to quichDASH postoperative score of 9 (range: 0–25). Conclusion Ultrasound-guided percutaneous release in the de Quervain's disease is a safe and reliable procedure without specific morbidity. Great care should be taken to avoid sensory nerve injuries and to identify the correct type of subcompartmentalization with a precise ultrasound evaluation.

Extensor pollicis longus rerouting for thumb-in-palm deformity in cerebral palsy: a biomechanical analysis

Extensor pollicis longus rerouting is a common procedure to improve thumb abduction in thumb-in-palm deformity seen with spastic cerebral palsy. In 1985, Manske redirected the extensor pollicis longus tendon in this procedure through the first extensor compartment. They also proposed an alternative subcutaneous route around the extensor pollicis brevis and abductor pollicis longus tendons proximal to the extensor compartment. In this study, we performed a three-dimensional analysis of thumb motion on 11 cadaver arms with the subcutaneous route and the first extensor compartment route. We found that with the two different routing methods, the mean difference in thumb radial abduction and retropulsion (0° or 6°, respectively) was very small. Such differences are unlikely to have clinical relevance. We were unable to find significant differences in the motion range of the thumb after these rerouting techniques or sites of insertion. Our biomechanical data support the simpler subcutaneous route.

Histological assessment of a septum in the first dorsal compartment: a fresh cadaver study

Resistance of de Quervain’s disease to conservative treatment has been associated with an intertendinous septum in the first compartment; little is known about the histological features of such a septum. This study aimed to examine the intertendinous septum histologically and note its variations. After dissecting the first extensor compartment of 24 hands from 12 fresh frozen cadavers, the presence of any intertendinous septa was determined. The length of the extensor retinaculum and intertendinous septum was measured; histological findings of the first compartment with or without septa were studied and compared with those of the third/fourth compartment. Intertendinous septa were observed in 12 of 24 wrists. Histological assessment of the intertendinous septum revealed tissue similar in composition to the retinaculum observed between the third and fourth compartments.