The early outcome of kinematic versus mechanical alignment in total knee arthroplasty: a prospective randomised control trial.

AIMS: Our aim was to compare kinematic with mechanical alignment in total knee arthroplasty (TKA). PATIENTS AND METHODS: We performed a prospective blinded randomised controlled trial to compare the functional outcome of patients undergoing TKA in mechanical alignment (MA) with those in kinematic alignment (KA). A total of 71 patients undergoing TKA were randomised to either kinematic (n = 36) or mechanical alignment (n = 35). Pre- and post-operative hip-knee-ankle radiographs were analysed. The knee injury and osteoarthritis outcome score (KOOS), American Knee Society Score, Short Form-36, Euro-Qol (EQ-5D), range of movement (ROM), two minute walk, and timed up and go tests were assessed pre-operatively and at six weeks, three and six months and one year post-operatively. RESULTS: A total of 78% of the kinematically aligned group (28 patients) and 77% of the mechanically aligned group (27 patients) were within 3° of their pre-operative plan. There were no statistically significant differences in the mean KOOS (difference 1.3, 95% confidence interval (CI) -9.4 to 12.1, p = 0.80), EQ-5D (difference 0.8, 95% CI -7.9 to 9.6, p = 0.84), ROM (difference 0.1, 95% CI -6.0 to 6.1, p = 0.99), two minute distance tolerance (difference 20.0, 95% CI -52.8 to 92.8, p = 0.58), or timed up and go (difference 0.78, 95% CI -2.3 to 3.9, p = 0.62) between the groups at one year. CONCLUSION: Kinematically aligned TKAs appear to have comparable short-term results to mechanically aligned TKAs with no significant differences in function one year post-operatively. Further research is required to see if any theoretical long-term functional benefits of kinematic alignment are realised or if there are any potential effects on implant survival. Cite this article: Bone Joint J 2016;98-B:1360-8.

Revision Total Knee Arthroplasty in a Patient with Bilateral Below-the-Knee Amputation: A Case Report.

UPDATE: This article was updated on January 27, 2016. The byline, which had previously read "M.G. Williams, MBChB, and J. Phillips, MBBS, FRCS," now reads "M.G. Williams, MBChB, J. Phillips, MBBS, FRCS, and K. Eyres, MD, FRCS(Tr&Orth)." In addition, the name, address, and e-mail address for Dr. Eyres have been added to the address block at the end of the article.An erratum has been published: JBJS Case Connect. 2016 Mar 23;6(1):e22. CASE: We report the case of a patient with bilateral below-the-knee amputation who had a periprosthetic fracture around a total knee arthroplasty. The fracture was managed with a revision total knee arthroplasty. We discuss the rationale for revision surgery, the surgical techniques, and the postoperative rehabilitation. Follow-up at one year demonstrated maintenance of the pretrauma functional status. CONCLUSION: In selected patients with a periprosthetic fracture, we believe that revision of a total knee arthroplasty may be considered as an option rather than an above-the-knee amputation or an arthrodesis.

A technique of fusion for failed total replacement of the ankle: tibio-allograft-calcaneal fusion with a locked retrograde intramedullary nail.

Salvage of a failed total ankle replacement is technically challenging and although a revision procedure may be desirable, a large amount of bone loss or infection may preclude this. Arthrodesis can be difficult to achieve and is usually associated with considerable shortening of the limb. We describe a technique for restoring talar height using an allograft from the femoral head compressed by an intramedullary nail. Three patients with aseptic loosening were treated successfully by this method with excellent symptomatic relief at a mean follow-up of 32 months (13 to 50).

Evaluation of patients with a painful total knee replacement.

Evaluation of patients with painful total knee replacement requires a thorough clinical examination and relevant investigations in order to reach a diagnosis. Awareness of the common and uncommon problems leading to painful total knee replacement is useful in the diagnostic approach. This review article aims to act as a guide to the evaluation of patients with painful total knee replacement.

An aid to femoral nail removal.

We describe a novel technique to aid the removal of a proximally inserted femoral nail by using a guide wire and the starter reamer. By reaming through the scar tissue, a cylindrical track is created and the threaded top end of the nail is exposed. The soft tissue dissection is therefore limited to the absolute minimum with no further damage to the hip abductors.

Irrigation and suction technique to ensure reliable cement penetration for total knee arthroplasty.

We describe a new technique to enhance the preparation of the cancellous bone surfaces in total knee arthroplasty using bone suction and pressure lavage irrigation. This technique provides dry bone surfaces on which to cement (which is particularly valuable if a tourniquet is not used) and improves significantly the penetration of cement into the tibial plateau as assessed on plain postoperative radiographs. We review the results of this new technique by analyzing depths of cement penetration on postoperative radiographs to assess whether this technique offers improvements in cement penetration and bone surface preparation. This technique offers a simple, quick, and reliable method of ensuring reliable cement penetration into the bony trabeculae during cemented total knee arthroplasty.

Vascular complications of osteotomies in limb reconstruction.

Osteotomies are commonly carried out in orthopaedic surgery, particularly in limb reconstruction. Complications are uncommon provided that sufficient care is taken and a sound technique used. We describe three cases of formation of false aneurysm after osteotomy, with acute, delayed and asymptomatic onset. The diagnosis was supported by ultrasound investigation, and confirmed by angiography. Embolisation with coils was a successful method of treatment. We recommend a safe method of osteotomy with good bone exposure and adequate soft-tissue protection.

Safe removal of massive intrapelvic cement using ultrasonic instruments.

The extraction of massive intrapelvic deposits of cement in revision total hip arthroplasty presents the surgeon with a philosophical dilemma and a technical challenge. The cement is difficult to remove because of the disparity between the size of the cement mass and the defect in the acetabulum. In addition, the cement mass lies close to major intrapelvic organs, and the use of force applied with sharp cement-removing instruments poses a danger to these structures. We report on the ultrasonic technique of cement removal used to extract a massive intrapelvic cement deposit safely.

Posterior surgical treatment for the rheumatoid cervical spine.

Twenty-six patients with rheumatoid disease affecting the cervical spine underwent surgical treatment for neck pain, neurological deficit, or both. Atlantoaxial subluxation (n=13), subaxial subluxation (n=7) and vertical migration of the odontoid (n=6) were treated. Arthrodesis with autologous bone was augmented with wire, Ransford loop, Hartshill rectangle or Magerl technique. Pain relief occurred in 92% of patients. Neurological deficit improved in 89% and was unchanged in the remainder. Radiographic stability was achieved in all but one patient. Posterior surgery effectively relieved pain and neurological deficit, and the complications encountered did not jeopardize the outcome.

Effect of pulsed electromagnetic fields on bone formation and bone loss during limb lengthening.

We examined the effect of pulsed electromagnetic fields (PEMFs) on bone formation and disuse osteoporosis sustained during limb lengthening in a double-blind study. Seven males (mean age 13 years, range 11-19 years) and six females (mean age 12 years, range 9-19 years) were randomly allocated to receive either an active or an inactive PEMF coil. Limb lengthening was performed by the Villarubbias technique using either a unilateral or circular frame system. Sequential bone density measurements were made using dual energy X-ray absorptiometry and compared to traditional radiographs. Ten segments (eight tibial and two femoral) in seven patients were lengthened under the influence of active coils and eight segments (six tibial and two femoral) in six patients using inactive coils. There was no difference in the rate nor the amount of new bone formed at the site of distraction between the two groups. Bone loss in the segments of bone distal to the lengthening sites was observed in both groups but was significantly more marked using inactive coils (BMD reduced by 23% +/- SEM 3% and 33% +/- 4% control values after one and two months, respectively; p < 0.0001) than using active coils (BMD reduced by 10% +/- 2% at 2 months). These differences were greater at 12 months after surgery (reduced by 54% +/- 5% and 13% +/- 4%, respectively; p < 0.0001). Stimulation with pulsed electromagnetic fields has no effect on the regenerate bone, but does prevent bone loss adjacent to the distraction gap.