The aim of this study was to evaluate the effects of using a
portable, accelerometer-based surgical navigation system (KneeAlign2)
in total knee arthroplasty (TKA) on the alignment of the femoral
component, and blood loss. A total of 241 consecutive patients with primary osteoarthritis
of the knee were enrolled in this prospective, randomised controlled
study. There were 207 women and 34 men. The mean age of the patients
was 74.0 years (57 to 89). The KneeAlign2 system was used for distal
femoral resection in 121 patients (KA2 group) and a conventional intramedullary
femoral guide was used in 120 patients (IM group).Aims
Patients and Methods
Severe hallux valgus deformity is conventionally
treated with proximal metatarsal osteotomy. Distal metatarsal osteotomy
with an associated soft-tissue procedure can also be used in moderate
to severe deformity. We compared the clinical and radiological outcomes
of proximal and distal chevron osteotomy in severe hallux valgus deformity
with a soft-tissue release in both. A total of 110 consecutive female
patients (110 feet) were included in a prospective randomised controlled
study. A total of 56 patients underwent a proximal procedure and
54 a distal operation. The mean follow-up was 39 months (24 to 54)
in the proximal group and 38 months (24 to 52) in the distal group.
At follow-up the hallux valgus angle, intermetatarsal angle, distal
metatarsal articular angle, tibial sesamoid position, American Orthopaedic
Foot and Ankle Society (AOFAS) hallux metatarsophalangeal-interphalangeal
score, patient satisfaction level, and complications were similar
in each group. Both methods showed significant post-operative improvement
and high levels of patient satisfaction. Our results suggest that
the distal chevron osteotomy with an associated distal soft-tissue
procedure provides a satisfactory method for correcting severe hallux
valgus deformity. Cite this article:
We prospectively studied the use of intercostal EMG monitoring as an indicator of the accuracy of the placement of pedicle screws in the thoracic spine. We investigated 95 thoracic pedicles in 17 patients. Before insertion of the screw, the surgeon recorded his assessment of the integrity of the pedicle track. We then stimulated the track using a K-wire pedicle probe connected to a constant current stimulator. A compound muscle action potential (CMAP) was recorded from the appropriate intercostal or abdominal muscles. Postoperative CT was performed to establish the position of the screw. The stimulus intensity required to evoke a muscle response was correlated with the position of the screw on the CT scan. There were eight unrecognised breaches of the pedicle. Using 7.0 mA as a threshold, the sensitivity of EMG was 0.50 in detecting a breached pedicle and the specificity was 0.83. Thoracic pedicle screws were accurately placed in more than 90% of patients. EMG monitoring did not significantly improve the reliability of placement of the screw.
