RESUMEN
BACKGROUND: Volar locking plate fixation may offer several advantages over headless screw fixation for scaphoid nonunion, or segmental or comminuted fractures: (1) increased surface area for bony healing; (2) preserved vascularity; and (3) maintenance of a gap for graft insertion. The purpose of this study is to compare headless screw and locking plate fixation of segmental scaphoid fractures and to determine whether either fixation provides a greater mechanical advantage in osteoporotic versus nonosteoporotic bone. METHODS: Sixteen matched-pair cadaver scaphoids were dissected from a range of osteoporotic and nonosteoporotic specimens. Scaphoids from each matched pair were randomly assigned to either volar locking plate or compression screw fixation. A 3-mm segment of bone was circumferentially excised from each scaphoid waist to simulate a segmental defect. Implants were applied, and each specimen was then loaded in axial compression. Load to failure was defined as the load required to achieve gap closure. Mechanism of failure, load to failure, and percent gap recovery were recorded for each trial. RESULTS: Gap closure occurred in all trials. Difference in load to failure was not statistically significant between plate and screw fixation in either nonosteoporotic or osteoporotic cadaver specimens. However, percent gap recovery was significantly higher for plate fixation than for screw fixation. CONCLUSIONS: In scaphoid fractures with segmental defect, plate and screw fixation demonstrate similar loads to failure, but plate fixation performs superiorly to screw fixation for gap recovery after an applied load to failure.
Asunto(s)
Placas Óseas , Tornillos Óseos , Fijación Interna de Fracturas/instrumentación , Fracturas no Consolidadas/cirugía , Hueso Escafoides/cirugía , Fenómenos Biomecánicos/fisiología , Cadáver , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/fisiopatología , Estrés MecánicoRESUMEN
Studies continue to demonstrate the importance of the anterolateral ligament (ALL) as a secondary restraint in rotational stability of the knee. No clinical exam exists to reliably test the ALL. Advanced imaging allows the surgeon to reliably identify the ALL as an independent structure of the lateral knee. This technique paper provides a reproducible method for identification of the ALL on 3T magnetic resonance imaging based on previously conducted cadaveric dissections of the ligament.
RESUMEN
Iliopsoas impingement is an uncommon cause of pain after total hip arthroplasty. If pain persists after a trial of conservative treatment, surgical intervention can alleviate the patient's symptoms. Multiple advantages exist to release the iliopsoas tendon at the level of the lesser trochanter. The purpose of this Technical Note is to demonstrate a technique for arthroscopic release of the iliopsoas tendon at the lesser trochanter after total hip arthroplasty.
RESUMEN
Ischiofemoral impingement is a newly recognized cause of extra-articular hip pain, and is caused by contact between the lesser trochanter and ischium. Surgical intervention has been proven successful for patients with persistent pain and disability after failure of nonoperative management. This technique article provides a reliable method for endoscopic lesser trochanter osteoplasty using an anterior approach.