Correlation of the Lateral Wrist Radiograph to Ulnar Variance: A Cadaveric Study.

PURPOSE: Both positive and negative ulnar variance have been implicated in a variety of wrist disorders. Surgery aims to correct the variance in these pathologic conditions. This necessitates accurate and reproducible measuring tools; however, the most accurate radiographic measurement technique remains unclear. The purposes of this study were to evaluate 3 methods for determining ulnar variance and to compare each with direct anatomic measurement in a cadaver model. METHODS: We fixed 10 fresh above-elbow cadaver specimens in neutral rotation and obtained standardized fluoroscopic posteroanterior and lateral wrist images. A dorsal approach was performed and two independent investigators directly measured ulnar variance using digital calipers with the cartilage both intact and denuded. Ulnar variance was measured radiographically using the lateral, perpendicular, and central reference point methods. The reliability of each set of measurements (within a 1-mm cutoff) was assessed by the intraclass coefficient; agreement between radiographic and direct measurements was evaluated by the Bland-Altman method. RESULTS: Each method of determining ulnar variance demonstrated near perfect agreement by the intraclass coefficient. The lateral radiograph method correlated highly with the directly measured ulnar variance with the cartilage denuded with an average measurement difference of 0.06 mm. No radiographic measurement technique demonstrated consistent agreement within 1 mm of the measured ulnar variance with the cartilage intact. CONCLUSIONS: Ulnar variance measured by the lateral wrist radiograph technique correlates highly with the directly measured osseous ulnar variance. The remaining measurement techniques did not correlate reliably to within 1 mm of the directly measured ulnar variance with 95% confidence. No method was able to account accurately for the articular cartilage thicknesses at the lunate facet of the radius or the distal ulnar head, which we found to vary in an unpredictable manner. Whereas the lateral radiograph has been shown to allow for more reliable standardization of wrist position compared with the posteroanterior view, this study also highlights the inherent limitations of using static radiographic images in evaluating ulnar variance. CLINICAL RELEVANCE: The results of the current study demonstrate the utility of the lateral wrist radiograph for assessing bony ulnar variance.

A Cadaver Investigation of Screw Purchase With 2 Retrograde Techniques for Capitolunate Arthrodesis.

PURPOSE: To examine the hypothesis that the amount of bone purchase within the lunate is greater when using a technique for intermetacarpal retrograde screw placement across the capitolunate joint than when using a dorsal capitate technique. METHODS: Seven fresh cadaver limbs were dissected. We exposed the carpus and scaphoidectomy and performed selective capitolunate decortication. We compared the technique of dorsal capitate placement of headless compression screws with intermetacarpal placement by measuring the depth of purchase in the lunate. RESULTS: Drill hole depths in the lunate were greater using the intermetacarpal technique versus the dorsal capitate technique; the average depth was 9.0 and 6.4 mm, respectively. The calculated number of threads was also greater with the intermetacarpal technique than with the dorsal capitate technique (15 vs 9 threads, respectively). CONCLUSIONS: The intermetacarpal technique for retrograde headless compression screw placement in a capitolunate arthrodesis provided a greater depth of purchase in the lunate portion of the construct. It also afforded more ease of placement than previously described antegrade techniques without the risk of hardware migration into the radiocarpal joint. CLINICAL RELEVANCE: The knowledge gained from this study may help guide surgeons to choose a technique for retrograde placement of headless compression screws in capitolunate arthrodesis to gain better purchase within the lunate.

Trapeziectomy Arthroplasty With Suture Suspension: Short- to Medium-Term Outcomes From a Single-Surgeon Experience.

PURPOSE: To describe the technique and a single-surgeon experience with a suture suspension and first dorsal compartment release treatment for thumb trapeziometacarpal (TMC) osteoarthritis. METHODS: We performed 19 procedures on 18 patients using this technique and compared results with preoperative assessment. At an average of 20 months (range, 8-45 months) after surgery, standard measures after TMC joint arthroplasty were performed. RESULTS: All patients had advanced Eaton stage III or IV osteoarthritis. Grip strength, key pinch, and thumb abduction showed statistically significant increases of 7 kg, 0.7 kg, and 4°, respectively. Seventeen of 18 patients no longer had reports of TMC joint pain on follow-up. There was one reoperation for pain because of osteophytes at the ulnar surface of the thumb metacarpal base, which resolved with proximal metacarpal excision. One case of index metacarpal fracture was treated with an orthosis. CONCLUSIONS: This surgical technique for the treatment of thumb TMC joint arthritis achieved pain relief and recreated support of the base of the metacarpal to resist proximal migration or radial deviation. This technique also provided an increase in grip strength and key pinch with return of range of motion early in the postoperative period. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Ultrasound localization of a tunneled leech beneath a microvascular scalp reconstruction: A case report.

Medicinal leech therapy is a common adjuvant modality used to treat venous congestion following threatened microvascular anastomosis. Migration and tunneling of a leech beneath a surgical reconstruction is a rare event that is seldom mentioned in the literature and worthy of further discussion. We present a rectus abdominus myocutaneous free tissue transfer that was used to cover a large alloplastic cranioplasty following resection of a previously radiated skull base malignant meningioma. The flap became congested postoperatively and required leech therapy after surgical salvage. Three days after flap salvage, the subject was once again brought back to the operating room for surgical exploration when a leech was witnessed to migrate beneath the threatened free flap. Duplex ultrasound was used intra-operatively to localize the leech 12 cm from its bite and assist with its successful removal. Tunneling of the leech beneath the flap is a rare complication, and localization underneath a myofascial or myocutaneous flap may be difficult. Duplex ultrasound is a simple and reliable method to localize the leech and allow for its removal through a minimal access incision.

Phototoxicity in an ultraviolet ink manufacturing plant.

Ultraviolet (UV) dyes are used as inks in garment printing. Hypersensitivity reactions to these compounds have been reported in the literature. The authors report a case of reaction to UV ink in a patient already on corticosteroid therapy. The patient's clinical course was reviewed along with images of wounds that subsequently developed. The affected areas were debrided and covered with Vaseline gauze and silver impregnated dressings. Epithelium was salvaged in many areas, and regrowth occurred over several weeks in regions of deeper injury. The concurrent use of steroids and the rapidity of the onset of symptoms were not characteristic of hypersensitivity dermatitis, which has previously been reported. The cause of the wounds was likely phototoxicity from radical subtypes in the ink that catalyze the reaction when exposed to UV light.