Anatomic Variation of the Hamate Hook as a Potential Risk in Endoscopic Carpal Tunnel Release.

Purpose: The purpose of this study was to investigate the incidence of anomalies in patients who underwent endoscopic carpal tunnel release and their relationship with clinical outcomes. Methods: This retrospective study included 65 hands of 57 patients (8 men and 49 women; mean age, 64.9 years) who underwent endoscopic carpal tunnel release for carpal tunnel syndrome at our hospital between March 2016 and April 2022. The patients were diagnosed with carpal tunnel syndrome based on clinical observations and electrophysiological studies. On T2-weighted magnetic resonance axial images, the height of the hook of the hamate was measured from the bottom to the tip of the hook, and the total height of the hamate was measured from the dorsal surface of the hamate to the tip of the hook. A hook-to-height ratio of less than 0.34 was defined as hypoplastic, and its incidence was investigated. In addition, electrodiagnostic testing of sensory and motor nerve conduction of the median nerve and patient-reported outcome measurements, including Quick Disabilities of the Arm, Shoulder and Hand score, Boston carpal tunnel questionnaire, and visual analog scale score, were investigated at 6 months after surgery. Adverse events were collected from patient records. Results: The mean hook-to-height ratio was 0.40. Hypoplasia with a ratio ≤0.34 was observed in seven hands (10.8%), and adverse events were observed only in the two cases that had a hypoplastic hook of the hamate (3.07%). The patient-reported outcome measurements and the result of electrodiagnostic testing at 6 months after surgery did not correlate with the height of the hook of the hamate. Conclusions: The incidence of a hypoplastic hook of the hamate is common in patients with carpal tunnel syndrome, and preoperative evaluation of the morphology of the hooks and indications for endoscopic carpal tunnel release in cases of hypoplastic hooks may help predict adverse events. Type of study/level of evidence: Therapeutic Ⅳ.

Reconstruction of a Composite Defect of the Distal Index Finger Using a Chimeric Reverse Flow Second Dorsal Metacarpal Artery Flap: A Case Report.

The reconstruction for mild tissue loss at the distal part of a finger is challenging. We report about a 29-year-old man presenting with traumatic tissue loss at the distal interphalangeal (DIP) joint of the index finger, including skin, bone, and nerve. Reconstruction using two types of flaps was performed. The dorsal skin flap, nourished by the second dorsal metacarpal artery (SDMA) perforator, was elevated. The vascularized second metacarpal bone, nourished by the SDMA, was also elevated. Using the vascular connection between the DMA and the palmar digital artery (PDA), both flaps were raised to the distal part of the finger, and the pivot point was set at the dorsal proximal phalanx. After arthrodesis of the DIP joint with the vascularized second metacarpal bone, the digital nerve was repaired using the cutaneous nerve in the skin flap, and the skin defect was covered using the perforator flap. The postoperative course, including flap survival and bone union, was uneventful. A good indication for the reconstruction of the distal part of a finger with this technique is when the defect sizes of the skin and bone differ and the vascular connection between the SDMA and dorsal branch of PDA is not injured.

Use of digital artery perforator flaps for repairing soft tissue defects after fasciectomy for Dupuytren's contractures in the ring and little fingers: A case report.

Fasciectomy is the standard treatment for Dupuytren's contracture, but, in many cases, skin defects may occur after fasciectomy. If the preoperative contracture is severe, the skin defect is large, which makes covering the defect difficult. We describe a case of severe skin defects after fasciectomy of Dupuytren's contractures in the ring and little fingers covered with multiple digital artery perforator (DAP) flaps . A 58-year-old man with extension restrictions of the ring and little fingers on his left hand was diagnosed with Dupuytren's contracture. The angles of insufficient extension were 70° and 40° for the metacarpophalangeal and proximal interphalangeal joints, respectively, of the little finger and 42° for the metacarpophalangeal joint of the ring finger. DAP flaps were used to cover the defect on the ring finger's metacarpophalangeal joint and little finger's proximal interphalangeal joint, whereas an ulnar palmar DAP flap was used on the defect on the little finger's metacarpophalangeal joint. The flaps survived without any complications, and, at 6 months postoperatively, satisfactory results were obtained. The extension angles were 0° for the metacarpophalangeal and proximal interphalangeal joints of the little finger and -5° for the ring finger's metacarpophalangeal joint. Such flaps can be designed to fit the width of the skin defect and can be applied to a large skin defect by combining the perforator flaps. Thus, the use of DAP flaps after fasciectomy to cover defects is considered helpful, even in cases of Dupuytren's contracture with severe extension restriction.

High Median Nerve Entrapment by Fracture Callus in Surgically Treated Pediatric Supracondylar Humeral Fracture: A Case Report.

CASE: We describe a patient with incomplete high median nerve palsy after surgical treatment of pediatric supracondylar humeral fracture (SCHF). Preoperative images after 11 months after the surgical treatment of the SCHF showed rotational deformity and an isolated median nerve entrapped between the proximal humerus anteriorly and callus posteriorly in the bony tunnel of the distal humerus. Two years after neurolysis, he showed clinical recovery. Four cases similar to our case were reported previously. CONCLUSION: Common pediatric fractures may cause unusual neuropathy. Rotational deformity of fracture might be an important factor for isolated median nerve entrapment after SCHF.

Identification of Ulnar Artery Perforators Using Color Doppler Ultrasonography.

BACKGROUND: The ulnar artery perforator (UAP) flap, which is hairless, thin, and pliable, has been used for the reconstruction of soft tissues from the finger to the elbow. Preoperative planning is essential for a perforator flap surgery, and there are some tests to identify perforators. Color Doppler ultrasonography (US) with a high-frequency transducer helps in detecting decreased flow in smaller vessels, such as perforators. The purpose of this study was to determine the anatomical locations and origins of perforators arising from the ulnar artery using color Doppler US in healthy volunteers. METHODS: Forty forearms of 20 healthy volunteers were included in the study. Perforators arising from the ulnar artery, within 100 mm proximal to the pisiform, were investigated using color Doppler US with a high-frequency transducer. RESULTS: A total of 205 perforators were identified. On comparing the locations in each 20 mm section from the pisiform, the largest number of perforators was 58 (28%), within 20 mm proximal to the pisiform. The axial view demonstrated 44 (21%), 64 (31%), 32 (16%), and 65 (32%) perforators in the radial, ulnar, superficial, and deep aspects of the ulnar artery, respectively. Fifty-two and 28 essential perforators were supplied by the UAPs arising from the superficial and ulnar aspect within 20 mm proximal to the pisiform and between 21 and 40 mm proximal to the pisiform, respectively, while elevating the UAP flap. CONCLUSION: This is the first study to assess the UAP using color Doppler US. Identification of UAP using color Doppler US can be used as a preoperative assessment for reliable elevation of a UAP flap.