Bone mineralization is elevated and less heterogeneous in adults with type 2 diabetes and osteoarthritis compared to controls with osteoarthritis alone.

PURPOSE: The purpose of this study was to determine whether trabecular bone mineralization differed in adults with type 2 diabetes compared to adults without type 2 diabetes. METHODS: Proximal femur specimens were obtained following a total hip replacement procedure from men and women ≥65 years of age with and without type 2 diabetes. A scanning electron microscope was used for quantitative backscattered electron imaging (qBEI) analysis of trabecular bone samples from the femoral neck. Gray scale images (pixel size=5.6 µm(2)) were uploaded to ImageJ software and gray level (GL) values were converted to calcium concentrations (weight [wt] % calcium [Ca]) using data obtained with energy dispersive X-ray spectrometry. The following bone mineralization density distribution (BMDD) outcomes were collected: the weighted mean bone calcium concentration (CaMEAN), the most frequently occurring bone calcium concentration (CaPEAK) and mineralization heterogeneity (CaWIDTH). Differences between groups were assessed using the Student's t-test for normally distributed data and Mann-Whitney U-test for non-normally distributed data. An alpha value of <0.05 was considered significant. RESULTS: Thirty-five Caucasian participants were recruited (mean [standard deviation, SD] age, 75.5 [6.5]years): 14 adults with type 2 diabetes (years since type 2 diabetes diagnosis, 13.5 [7.4]years) and 21 adults without type 2 diabetes. In the adults with type 2 diabetes, bone CaMEAN was 4.9% greater (20.36 [0.98]wt.% Ca versus 19.40 [1.07]wt.% Ca, p=0.015) and CaWIDTH was 9.4% lower (median [interquartile range] 3.55 [2.99-4.12]wt.% Ca versus 3.95 [0.71]wt.% Ca, p<0.001) compared to controls. There was no between-group difference in CaPEAK (21.12 [0.97]wt.% Ca for type 2 diabetes versus 20.44 [1.30]wt.% Ca for controls, p=0.121). CONCLUSION: The combination of elevated mean calcium concentration in bone and lower mineralization heterogeneity in adults with type 2 diabetes may have deleterious effects on the biomechanical properties of bone. These microscopic alterations in bone mineralization, which may be mediated by suppressed bone remodeling, further elucidate higher fracture risk in adults with type 2 diabetes.

Modified iliofemoral approach for major isolated acetabular revision arthroplasty.

Multiple specialized exposures have been described for revision total hip arthroplasty. In this article, we report on a series of 7 patients who underwent major isolated acetabular revision surgery through a modified iliofemoral approach. The use of this approach was deemed desirable because of the individual pathology present in each case, particularly major acetabular bone loss (Paprosky 2C/3B). However, successful reconstruction was achieved in all cases with the most frequent complication being meralgia paresthetica.

Perfect balance in total knee arthroplasty: the elusive compromise.

A Tensor/Balancer device (Stryker Howmedica Osteonics, Allendale, NJ) was used to restore optimal stability and alignment during 83 consecutive total knee arthroplasties with a minimum of 6-week clinical and radiographic follow-up. The surgical technique is described. Mean flexion-extension symmetry was restored to within 1 degrees. Mean femoral rotation required to achieve symmetry in flexion differed between varus (4.38 degrees ) and valgus (6.0 degrees ) knees. Of 83 knees, 7 had >3 mm of subjective laxity during component trialing and were associated with a preoperative deformity of >15 degrees; 19 knees required femoral rotation of >6 degrees and were associated with greater preoperative malalignment. Postoperative knee alignment, range of motion, Knee Society score, and lateral release rate were similar between the 2 groups. The use of a Tensor/Balancer device in total knee arthroplasty can achieve outcomes comparable to existing techniques with potential for improved technical accuracy.

Acute colonic pseudo-obstruction after elective total joint arthroplasty.

A retrospective review of 31 patients who developed acute colonic pseudo-obstruction (ACPO) after total joint arthroplasty was undertaken to determine predisposing factors related to, and outcomes following, therapeutic intervention. Comparison with all patients who underwent total joint arthroplasty revealed an overall 1.2% incidence of ACPO. There was a higher incidence of ACPO in patients undergoing sequential bilateral total knee arthroplasty (3.4%) compared with unilateral total knee arthroplasty (0.3%) and a higher incidence in patients undergoing revision total hip arthroplasty (5.6%) compared with primary total hip arthroplasty (1.4%). Additional risk factors for developing ACPO included slow postoperative mobilization and male gender. No association was found with respect to body mass index, age, comorbidity, anesthetic type, international normalized ratio level, or postoperative analgesia. There were no deaths, and 2 patients required operative intervention. The remaining cases of ACPO resolved with nonsurgical treatment. In all cases, there was a prolonged length of hospitalization (mean, 13.2 days) compared with all other arthroplasties performed at our institution (mean, 7.5 days).

Arteriovenous malformation mimicking femoral osteolysis after total hip arthroplasty.

We encountered a case of apparent progressive femoral osteolysis around a well-fixed cementless implant in a young patient. At the time of revision arthroplasty, massive hemorrhaging occurred during exposure and attempted femoral component extraction. Urgent packing of the exposed endosteum with polymethyl methacrylate controlled the bone bleeding. Emergent angiography confirmed an arteriovenous malformation with extensive proximal diaphyseal involvement directly at the site of osteolysis. This arteriovenous malformation was treated successfully with selective arterial embolization and second-stage resection. In retrospect, the index arthroplasty operative note indicated an excessive amount of blood loss, and prerevision radiographs showed osteolysis with uncharacteristic vascular markings. The presence of an osteolytic lesion in total hip arthroplasty should not be assumed to be attributed to polyethylene granuloma, and any atypical radiographic features should prompt further preoperative investigations.

Load relaxation and forces with activity in Hoffman external fixators: a clinical study in patients with Colles' fractures.

A small-frame Hoffman external fixation bar instrumented with strain gauges to quantify bending and torsional forces was applied to 4 patients with a displaced metaphyseal fracture of the distal radius. Measurements were taken during surgery as well as at 1, 3, and 6 weeks after surgery during activities of daily living and hand therapy mobilization. Radiographs also were taken before and after reduction and at each subsequent visit. Force decay occurred after reduction of the fracture, averaging only 26% of the initial distraction forces by 5 minutes. These forces plateaued and did not significantly change over the subsequent 40-minute observation period. There was no correlation between carpal height index and the forces measured in the external fixator. Significant changes in external fixator forces were measured during activities of daily living and hand therapy mobilization, but these returned to baseline after the activities were performed. The most provocative activities studied were twisting a doorknob and lifting heavy objects. These activities should be performed with caution by patients with unstable distal radial fractures.

The Harris Design-2 total hip replacement fixed with so-called second-generation cementing techniques. A ten to fifteen-year follow-up.

We analyzed the clinical results of 195 Harris Design-2 total hip replacements performed with so-called second-generation cementing techniques in 166 consecutive patients who had osteoarthrosis. The mean age of the patients at the time of the replacement was sixty-seven years and nine months (range, thirty-one to eighty-nine years). Forty-eight patients (fifty-four hips) died before the time of the latest follow-up, but the implants were apparently functioning well at the time of death. Three patients (four hips) were lost to follow-up. Five patients (five hips; 3 percent) had a revision because of aseptic loosening of the acetabular or femoral component, or both, that was related to wear-induced osteolysis. The mean Harris hip score for the 131 hips that were available at the latest follow-up examination at a mean of twelve years (range, ten to fifteen years) after the operation was 89 +/- 10 points. On the basis of the Harris hip score, seventy-six hips had an excellent result, thirty-four had a good result, fifteen had a fair result, and six had a poor result at the latest follow-up examination. Radiographically, twelve (9 percent) of the 131 acetabular components and three (2 percent) of the 131 femoral components were probably or definitely loose. At a mean of twelve years, 186 (97 percent) of 191 Harris Design-2 implants were in situ or had been in situ at the time of the patient's death.

Comparison of bioabsorbable pins and Kirschner wires in the fixation of chevron osteotomies for hallux valgus.

A retrospective review of the medical records and radiographs of 32 consecutive patients, totaling 52 extremities with chevron osteotomies for hallux valgus, was conducted to compare K wire fixation with absorbable (poly-p-dioxanone) pin fixation. Each group comprised 21 feet, with a mean clinical follow-up of 35.6 months (25.6-50.5 months) in the K wire group and 23.1 months (13.7-28.8 months) in the absorbable pin group. Demographics as well as final clinical follow-up scores (hallux-metatarsophalangeal-interphalangeal scale and visual analogue scores) were similar in both groups. Postoperative hallux valgus and intermetatarsal angles were similar in both groups. No complications, such as osteolysis for inflammatory sinus formation, occurred in the absorbable pin group. Two patients in the K wire group had a malunited osteotomy and two patients had a retained K wire at final follow-up. Our experience suggests that poly-p-dioxanone pins are at least as effective as K wires, and the previous reports of inflammatory sinus formation and osteolysis are not a significant concern in the fixation of chevron osteotomies for hallux valgus.

Combination alkali/thermal burns caused by 'black liquor' in the pulp and paper industry.

Three patients are presented, who sustained a unique type of burn injury while working in the pulp and paper industry in Canada. These patients suffered combination chemical (pH 11-13) and thermal (85-95 degrees C) injuries, when they were exposed to 'black liquor'--a solution which is used in the pulp and paper industry to convert wood chips to pulp. Black liquor can rapidly cause devastating thermal-corrosive burns to the skin, eyes, lungs, and upper gastrointestinal tract. One patient sustained a relatively minor, full skin thickness 3 per cent body surface area (BSA) injury to both feet and lower legs. The second patient, who was sprayed with the heated black liquor solution, sustained a full skin thickness injury to 40 per cent BSA and also suffered virtual loss of vision in one eye. The third patient, who was also sprayed with the solution, sustained a 98 per cent full skin thickness burn and severe inhalation injury, and died during day 1 postburn. Photographic documentation of all three patients is presented. The principles of treatment of this type of burn injury are reviewed. All of these burns were preventable.

Orbital protrusion index in Treacher-Collins syndrome: a tool for determining the degree of soft-tissue damage.

The relationship of measurements of the intercanthal width (en-en), the biocular width (ex-ex) and both eye fissures (ex-en), constituting the orbital protrusion index ex-ex x 100 (en-en) + (en-ex, r) + (en-ex, l) was used to analyze preoperative morphological developments in the orbits of 23 patients with Treacher Collins syndrome. The index permitted distinction between mildly and severely defective orbits, based on the degree of defective measurements and variations in relative sagittal positions. Optimal index values (mean, 94.0) were seen in 11 subjects with a slightly different sagittal level between the inner and outer commissures of the eye fissures, which created slightly protruding but still normal soft-tissue relief. The eye fissures in seven patients were moderately reduced in length. Orbits with higher indices (mean 98.1) (12 subjects) showed less differences in level between the two commissures of the eye fissures, producing a flattening in the surface relief. Eye fissure length was markedly subnormal in all patients.