Two-Step 3D-Guided Supramalleolar Osteotomy to Treat Varus Ankle osteoarthritis

BACKGROUND

Success of valgus-type supramalleolar osteotomy (SMOT) depends on adequate correction of malalignment, which can be hard to achieve with current 2-dimensional (2D) planning and operative techniques. A personalized digital 3-dimensional (3D) workflow to virtually plan and perform a 2-step 3D-guided medial opening (MO) SMOT has the potential to improve precision of correction.

METHODS

Computed tomography (CT)-based Proplan medical 3D models were made to virtually plan the desired MO SMOT, and exported to 3-Matic medical to develop patient-specific 2-step cutting and wedge guides. Workflow accuracy was tested in this limited clinical pilot study (3 patients) by comparing the virtual planned position of the osteotomized distal tibial fragment with the 1-year post-MO SMOT configuration. Two millimeters or less translation deviation in every plane was defined as accurate.

RESULTS

Primary outcome analysis of the osteotomized distal tibial fragment deviation showed a median translation in all planes of 0.7 (range 0-8.2) mm (interquartile range 1.55) with an excellent interrater reliability of the measurements (intraclass correlation coefficient 0.998). There was a strong reduction in ankle pain as reflected by an increase of the AOFAS-AH score and decrease of NRS pain score with an unrestricted hindfoot motion 1 year after surgery.

CONCLUSION

3D virtually planned bone cutting and wedge guides is a promising approach associated with minimal postoperative deviation from the desired correction in medial opening supramalleolar osteotomy.

Fatigue perceived by multiple sclerosis patients is associated with muscle fatigue

BACKGROUND

Fatigue is a debilitating symptom in multiple sclerosis (MS). Previous studies showed no association between fatigue as perceived by the patient and physiological measures of fatigability.

OBJECTIVE

The authors investigated associations between perceived fatigue and measures of fatigability after correction for differences in maximal voluntary contraction (MVC).

METHODS

A total of 20 people with relapsing-remitting MS with an Extended Disability Severity Score less than 5.5 and 20 healthy controls filled out the Fatigue Severity Score questionnaire of perceived fatigue. The authors obtained the MVC from the first dorsal interosseus muscle, voluntary muscle activation, and force decline during a sustained MVC (124 s, muscle fatigue).

RESULTS

Patients perceived increased levels of fatigue compared with controls (P < .001). Although patients and controls developed similar amounts of muscle fatigue during the sustained contraction, a linear regression model that included both muscle fatigue and MVC was positively associated with perceived fatigue in patients only (R (2) = 0.45; P = .01). Voluntary activation during the sustained contraction was negatively associated with perceived fatigue (R (2) = 0.25; P = .02).

CONCLUSION

The data indicate that fatigue perceived by MS patients is associated with measures of fatigability. This observation helps in the understanding of mechanisms underlying the increased levels of fatigue perceived by MS patients. These data also emphasize that for comparison of fatigue-related parameters between groups, correction for individual maximal force is essential.

Metabolic and calcium kinetic studies in idiopathic hypercalciuria

Calcium balances and calcium kinetic studies using (47)Ca were performed in nine male patients with idiopathic hypercalciuria and in three normal male subjects. A sharp reduction in calcium intake in eight patients with idiopathic hypercalciuria caused a decrease in urinary calcium excretion, the latter remaining elevated above that reported for normal subjects on a low calcium diet. The hypercalciuric patients had an enlarged miscible calcium pool size, an increased calcium turnover rate, increased bone formation and bone resorption rates, and an elevated true intestinal calcium absorption rate, the increase of the latter three parameters being proportional to the increase of the turnover rate. The fraction of the calcium turnover rate excreted in the urine was elevated whereas that constituted by the endogenous fecal calcium excretion was decreased. Arguments are presented for the concept that the primary abnormality in idiopathic hypercalciuria is neither renal calcium hyperexcretion nor intestinal calcium hyperreabsorption, but a more fundamental disturbance in calcium metabolism of as yet unknown cause, leading to a high calcium turnover.