Prevalence and Distribution of Thoracic and Lumbar Compressive Lesions in Cervical Spondylotic Myelopathy

Study DesignRetrospective cross-sectional study.PurposeThis study analyzed the prevalence and distribution of horacic and lumbar compressive lesions in cervical spondylotic myelopathy as well as their relationships with cervical developmental spinal canal stenosis (DCS) by using whole-spine postmyelographic computed tomography.Overview of LiteratureThere are few studies on missed compressive lesions of the spinal cord or cauda equina at the thoracolumbar level in cervical spondylotic myelopathy. Furthermore, the relationships between DCS, and the prevalence and distribution of thoracic and lumbar compressive lesions are unknown.MethodsEighty patients with symptomatic cervical spondylotic myelopathy were evaluated. Preoperative image data were obtained. Patients were classified as DCS or non-DCS (n=40 each) if their spinal canal longitudinal diameter was <12 mm at any level or ≥12 mm at all levels, respectively. Compressive lesions in the anterior and anteroposterior parts, ligamentum flavum ossification, posterior longitudinal ligament ossification, and spinal cord tumors at the thoracolumbar levels were analyzed.ResultsCompressive lesions in the anterior and anteroposterior parts were observed in 13 (16.3%) and 45 (56.3%) patients, respectively. Ligamentum flavum and posterior longitudinal ligament ossification were observed in 19 (23.8%) and 3 (3.8%) patients, respectively. No spinal cord tumors were observed. Thoracic and lumbar compressive lesions of various causes tended to be more common in DCS patients than non-DCS patients, although the difference was statistically insignificant.ConclusionsSurveying compressive lesions and considering the thoracic and lumbar level in cervical spondylotic myelopathy in DCS patients are important for preventing unexpected neurological deterioration and predicting accurate neurological condition after cervical surgery

Bilateral Greater Trochanteric Avulsion Fractures after Bilateral Simultaneous Total Hip Arthroplasty

We report a case of bilateral spontaneous greater trochanteric fracture after bilateral simultaneous total hip arthroplasty (THA) performed via the posterolateral approach during the early postoperative phase. A 75-year-old woman underwent bilateral simultaneous THA (BS-THA) for severe osteoarthritis with developmental dysplasia of the hip; she also presented a limited range of adduction. BS-THA was successful without any intraoperative complications. Rehabilitation with full weight-bearing exercises was initiated the day after the surgery. On the 14th postoperative day, she experienced a spontaneous left greater trochanteric fracture during a walking exercise without any trauma. Osteosynthesis was performed for the fracture on the 18th postoperative day. On the 20th postoperative day, a right spontaneous greater trochanteric avulsion fracture occurred during a transfer exercise without any trauma; this was treated on the 27th postoperative day. In the 18th postoperative month, although the right fragment showed slight upper migration, the patient had no complaints of coxalgia and both hip joints showed an excellent range of motion

Effects of cement anchors with screw holes for cementing a liner into a stable, cementless acetabular metal shell: A laboratory study

A mechanical study was conducted on the shell-cement interface in order to construct an acetabular metal shell, and to fix a polyethylene liner with the bone cement. Six types of models were tested. All cementations were performed under the similar conditions. The “lever out” test was conducted 3 times for each group in order to measure the dissociation strength. The average dissociation strength values were 11.5 N·m for those without screw holes; 33.6, 34.7, and 78.7 N·m for those with single holes at 1-, 3-, and 6-mm depth, respectively; and 41.3 and 101.1 N·m for the different configurations with three holes at 3-mm depth. The strength of adhesion increased with the use of a cement anchor and with increased lengths and numbers of anchors. The application of a cement anchor with a screw hole is clinically useful for increasing the mechanical strength of the shell-cement interface