Patients with diabetes mellitus may develop plantar flexion contractures (equinus) which may increase forefoot pressure during walking. In order to determine the relationship between equinus and forefoot pressure, we measured forefoot pressure during walking in 27 adult diabetics with a mean age of 66.3 years (. sd. 7.4) and a mean duration of the condition of 13.4 years (. sd. 12.6) using an Emed mat. Maximum dorsiflexion of the ankle was determined using a custom device which an examiner used to apply a dorsiflexing torque of 10 Nm (. sd. 1) for five seconds. Simple linear regression showed that the relationship between equinus and peak forefoot pressure was significant (p < 0.0471), but that only a small portion of the variance was accounted for (R. 2. = 0.149). This indicates that equinus has only a limited role in causing high forefoot pressure. Our findings suggest caution in undertaking of tendon-lengthening procedures to reduce peak forefoot plantar pressures in diabetic subjects until clearer indications are established

Although gradual bone transport may permit the restoration of large-diameter bones, complications are common owing to the long duration of external fixation. In order to reduce such complications, a new technique of bone transport involving the use of an external fixator and a locking plate was devised for segmental tibial bone defects.

A total of ten patients (nine men, one woman) with a mean age at operation of 40.4 years (16 to 64) underwent distraction osteogenesis with a locking plate to treat previously infected post-traumatic segmental tibial defects. The locking plate was fixed percutaneously to bridge proximal and distal segments, and was followed by external fixation. After docking, percutaneous screws were fixed at the transported segment through plate holes. At the same time, bone grafting was performed at the docking site with the external fixator removed.

The mean defect size was 5.9 cm (3.8 to 9.3) and mean external fixation index was 13.4 days/cm (11.8 to 19.5). In all cases, primary union of the docking site and distraction callus was achieved, with an excellent bony result. There was no recurrence of deep infection or osteomyelitis, and with the exception of one patient with a pre-existing peroneal nerve injury, all achieved an excellent or good functional result.

With short external fixation times and low complication rates, bone transport with a locking plate could be recommended for patients with segmental tibial defects.

Cite this article: Bone Joint J 2013;95-B:1667–72.

We compared lower limb coronal alignment measurements obtained pre- and post-operatively with long-leg radiographs and computer navigation in patients undergoing primary total knee replacement (TKR). A series of 185 patients had their pre- and post-implant radiological and computer-navigation system measurements of coronal alignment compared using the Bland-Altman method. The study included 81 men and 104 women with a mean age of 68.5 years (32 to 87) and a mean body mass index of 31.7 kg/m² (19 to 49). Pre-implant Bland–Altman limits of agreement were -9.4° to 8.6° with a repeatability coefficient of 9.0°. The Bland–Altman plot showed a tendency for the radiological measurement to indicate a higher level of pre-operative deformity than the corresponding navigation measurement. Post-implant limits of agreement were -5.0° to 5.4° with a repeatability coefficient of 5.2°. The tendency for valgus knees to have greater deformity on the radiograph was still seen, but was weaker for varus knees.

The alignment seen or measured intra-operatively during TKR is not necessarily the same as the deformity seen on a standing long-leg radiograph either pre- or post-operatively. Further investigation into the effect of weight-bearing and surgical exposure of the joint on the mechanical femorotibial angle is required to enable the most appropriate intra-operative alignment to be selected.

The results of primary total knee replacement performed on a group of haemophiliac patients in a single institution by the same surgeon using the same surgical technique and prosthesis are reported.

A total of 35 primary replacements in 30 patients were carried out between 1996 and 2005 and were reviewed retrospectively. The mean age of the patients was 31 years (24 to 42) and the mean follow-up was for 7.5 years (1 to 10). There were 25 patients with haemophilia A and five with haemophilia B. The HIV status and CD4 count were recorded, and Knee Society scores determined. Two patients had inhibitors to the deficient coagulation factor.

There were no early wound infections and only one late deep infection which required a two-stage revision arthroplasty, with a good final result. The incidence of infection in HIV-positive and negative patients was thus similar. One knee in a patient with inhibitor had excessive bleeding due to a pseudoaneurysm which required embolisation. The results were excellent in 27 knees (77%), good in six (17%) and fair in two (6%). The survival rate at 7.5 years taking removal of the prosthesis for loosening or infection as the end-point was 97%.

The mechanical survival of total knee replacements in haemophiliacs is very good. Our results confirm that this is a reproducible procedure in haemophilia, even in HIV-positive patients with a CD4 count > 200 mm³ and those with inhibitors. Our rate of infection was lower than previously reported. This could be due to better control of the HIV status with highly active anti-retroviral therapy and the use of antibiotic-loaded cement.