Yasuaki Nakanishi

Treatment of Kienböck disease in an 11-year-old girl with temporary fixation of the scaphotrapeziotrapezoidal joint

An 11-year-old girl with Kienböck disease (stage IIIA) was treated by temporary scaphotrapeziotrapezoidal fixation. It was fixed in a cast for four weeks and wires removed after eight weeks. Follow up examinations showed that movement of the wrist and grip strength were improved, and she had no pain while revascularisation of the lunate could be seen on magnetic resonance imaging.

Dynamic analysis of the ulnar nerve in the cubital tunnel using ultrasonography

BACKGROUND We investigated the dynamics of the ulnar nerve during elbow flexion and the relationships between these dynamics and the morphology of the ulnar nerve groove in healthy individuals. MATERIALS AND METHODS Twenty healthy volunteers (40 elbows) underwent ultrasonographic examination of the ulnar nerve at the elbow. We measured the breadth and depth of the ulnar nerve groove at 90° of elbow flexion and calculated the depth-to-breadth ratio. We recorded the distance from the trochlea of the humerus to the nerve and the short-axis diameter of the nerve at 30°, 60°, 90°, and 120° of elbow flexion. We calculated the medial shift and flattening of the ulnar nerve at each angle relative to 30° of flexion, compared the values among the different angles, and compared the depth-to-breadth ratio with the location, medial shift, and flattening ratio of the ulnar nerve. RESULTS The medial shift was significantly greater at 120° than at other angles (P < .001). Flattening increased with increasing elbow flexion and was significantly different at 60°, 90°, and 120° (all P < .001). The flattening ratios were significantly correlated with the depth-to-breadth ratio at 120° (r = -0.43, P = .005). CONCLUSIONS The ulnar nerve moves medially and is flattened with the elbow flexed between 90° and 120°. When the ulnar nerve groove is shallow, high degrees of elbow flexion result in flattening of the ulnar nerve in the groove.

Ultrasound-guided Selective Sensory Nerve Block for Wide-awake Forearm Tendon Reconstruction

Background: Wide-awake hand surgery is useful for tendon reconstruction because surgeons can observe the actual movement of the reconstructed tendons during the surgery. We hypothesized that accurate ultrasound-guided injection of local anesthetics into the sensory nerves contributes to reliable analgesia with a relatively small amount of anesthetic. Methods: We enrolled 8 patients who underwent forearm tendon transfer. Three patients underwent reconstruction of flexor tendon ruptures in zones 4 and 5, 3 underwent opponensplasty, and 2 underwent multiple tendon transfers according to Brand’s procedure. All patients underwent ultrasound-guided injection of ropivacaine to each sensory nerve branch of the upper arm and forearm and into the subfascial layer of the forearm. The mean amount of total ropivacaine was 193 mg. Results: In 7 of the 8 patients, we confirmed adequate active contraction of the flexor or extensor muscles during surgery. The expected active motion of the flexor pollicis longus was not found in 1 patient during surgery because the effect of the anesthetic had spread too widely, involving the motor branch of the median nerve. Two patients required additional infiltration of 2–3 mL of local anesthetic because of local wound pain. All patients gained satisfactory function of the transferred tendons after the surgery, and no remarkable perioperative complications related to local anesthetic systemic toxicity occurred. Conclusions: Selective administration of an anesthetic to the sensory nerve branches and subfascial layer enables the performance of wide-awake forearm tendon surgery. The ultrasound-guided injection technique provides safe and effective regional anesthesia for wide-awake surgery.

Biomechanical study of distal radioulnar joint ballottement test

We investigated the reliability and accuracy of the distal radioulnar joint (DRUJ) ballottement test using five fresh‐frozen cadaver specimens in triangular fibrocartilage complex (TFCC)‐intact, and TFCC‐sectioned wrists. The humerus and proximal ulna were fixed. The ulna was allowed to translate in dorsopalmar directions without rotation, and the radius was allowed to move freely. Four sensors of a magnetic tracking system were attached to the radius and ulna, and the nails of each examiners thumbs. Five examiners conducted the DRUJ ballottement test before and after TFCC sectioning. We used two techniques: With holding and without holding the carpal bones to the radius (holding and non‐holding tests, respectively). We compared the magnitudes of bone‐to‐bone (absolute DRUJ) movement with that of the examiners nail‐to‐nail (relative DRUJ) movement. The intrarater intraclass correlation coefficients (ICCs) were 0.92 (holding) and 0.94 (non‐holding). The interrater ICCs were 0.84 (holding) and 0.75 (non‐holding). Magnitudes of absolute and relative movements averaged 11.5 and 11.8 mm, respectively (p < 0.05). Before TFCC sectioning, the DRUJ movement during the holding and non‐holding techniques averaged 9.8 and 10.8 mm, respectively (p < 0.05). The increase in DRUJ movement after TFCC sectioning was greater with the holding technique (average 2.3 mm) than with the non‐holding technique (average 1.6 mm). The DRUJ ballottement test with magnetic markers is relatively accurate and reliable for detecting unstable joints. We recommend the holding technique for assessing DRUJ instability in clinical practice.

A Biomechanical Perspective on Distal Radioulnar Joint Instability

Background The purpose of this article was to review the anatomy, kinematics of the distal radioulnar joint (DRUJ), and to discuss definition, classification, and diagnosis of DRUJ instability. Methods A biomechanical perspective on physical examination of DRUJ ballottement test was documented. Physiological dynamic DRUJ translation and differences of the translation following sequential ligament sectioning and changes in different forearm and wrist positions were demonstrated. The clinical significance of each ligaments contribution to joint stability in specific wrist positions was addressed. Conclusion Each ligament stabilizing the DRUJ contributed to joint stability depending on the direction (palmer or dorsal) and different positions of the wrist and forearm. DRUJ ballottement test in each wrist and forearm position may detect tears of specific ligament stabilizing the DRUJ.

Obtaining Adequate Tension for Extensor Hallucis Longus Tendon Rupture Repair Using Wide-Awake Surgery: A Case Report

Wide-awake surgery has potential advantages for treating extensor or flexor tendon injury. We present a case of chronic extensor hallucis longus injury treated with turn-down reconstruction using wide-awake surgery with a selective nerve block. To the best of our knowledge, this is the first such case reported. The patient had dropped a knife proximal to the right hallux metatarsophalangeal joint. Because direct suturing was thought to be difficult, turn-down reconstruction was performed under a selective nerve block. At 8 months postoperatively, the hallux had 75° of extension in the metatarsophalangeal joint and -5° of extension in the interphalangeal joint, similar to those of the healthy foot. The Japanese Society for Surgery of the foot objective hallux scale score had improved from 87 to 100, and the subjective scores in the subcategories of pain and pain-related, physical functioning and daily living, and shoe-related in the self-administered foot evaluation questionnaire had improved from 82.8 to 94.4, 97.7 to 100, and 50 to 83.3, respectively. Turn-down reconstruction using wide-awake surgery with a selective nerve block can be used for chronic extensor hallucis longus rupture and can be expected to provide good results.

Septic arthritis of the wrist caused by Mycobacterium intracellulare: a case report

Abstract Septic arthritis of the wrist is rare entity, especially; atypical mycobacterial infection of the wrist is extremely rare. We report a case of septic arthritis of the wrist caused by Mycobacterium intracellulare, which was successfully treated by radical debridement followed by wrist arthrodesis using vascularised fibular grafting.