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.

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).

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.

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.

Unilateral lower limb hypoplasia in arterial fibromuscular dysplasia.

Hypoplasia or hyperplasia of limbs can be unilateral or bilateral and can involve the upper or lower extremities in any combination. The etiology is varied, and the presentation, clinical features, and investigative pathway differ to some extent among patients. Reported here is a child, referred for limb lengthening, with claudicating unilateral leg pain and unilateral hypoplasia of the same limb. Investigations revealed multiple arterial stenoses consistent with fibromuscular dysplasia. In such cases, early diagnosis and intervention with angioplasty may enhance subsequent growth of the limb, thus avoiding the need for limb lengthening procedures.

Comparison of three intravenous regimens of clodronate in Paget disease of bone.

We compared the effects of three different regimens of intravenous clodronate in a retrospective study of 60 patients with Paget disease. A total dose of 1500 mg of clodronate was given as 300 mg for 5 consecutive days (n = 20), 1500 mg as a single infusion (n = 20), or 300 mg as a single infusion for 5 consecutive months (n = 20). The response to treatment and the duration of the effect were assessed from sequential changes in the activity of serum alkaline phosphatase. Treatment with clodronate induced a significant response in 85% of patients. The response rate was comparable in patients treated with 5 daily infusions (90%), with a single infusion (75%), and with 5 monthly infusions (90%). The median duration of response from the start of treatment was 11 months for those treated with five daily infusions and 12 months for the other two regimens. At one year, 22, 40, and 44% of patients had maintained their response in the daily, single, and monthly infusion regimen, respectively (NS). Six patients (32%) treated with 5 daily infusions achieved a remission (complete response) compared with 3 patients treated with a single infusion and 5 monthly infusions, respectively (16 and 15% respectively, NS). Patients attaining a complete response had a significantly longer duration of response compared with partial responders (median time 15.0 versus 11.5 months, respectively, p < 0.05). We conclude that intravenous clodronate (total dose 1500 mg) suppresses disease activity in the majority of patients with Paget disease of bone. The degree and duration of response were similar for the three regimens. Thus, in the treatment of Paget disease, the choice of regimen is a matter of convenience.

Fractures of the coracoid process.

We have reviewed 12 fractures of the coracoid process. In two of these patients the fracture extended into the body of the scapula and resulted in displacement of the glenoid. In some cases, there were associated acromioclavicular and glenohumeral dislocations or fractures of the clavicle and the acromion. Two patients required internal fixation to restore congruence of the glenoid; the others were treated conservatively with success. We present a new classification of coracoid fractures which helps in their management.