Peri-prosthetic infection is amongst the most common causes of failure following total knee replacement (TKR). In the presence of established infection, thorough joint debridement and removal of all components is necessary following which new components may be implanted. This can be performed in one or two stages; two-stage revision with placement of an interim antibiotic-loaded spacer is regarded by many to be the standard procedure for eradication of peri-prosthetic joint infection.

We present our experience of a consecutive series of 50 single-stage revision TKRs for established deep infection performed between 1979 and 2010. There were 33 women and 17 men with a mean age at revision of 66.8 years (42 to 84) and a mean follow-up of 10.5 years (2 to 24). The mean time between the primary TKR and the revision procedure was 2.05 years (1 to 8).

Only one patient required a further revision for recurrent infection, representing a success rate of 98%. Nine patients required further revision for aseptic loosening, according to microbiological testing of biopsies taken at the subsequent surgery. Three other patients developed a further septic episode but none required another revision.

These results suggest that a single-stage revision can produce comparable results to a two-stage revision. Single-stage revision offers a reduction in costs as well as less morbidity and inconvenience for patients.

Cite this article: Bone Joint J 2014;96-B:759–64.

Introduction: The proximal femoral nail antirotation (PFNA) system is a cephalomedullary device originally designed to contend with the challenge of unstable tro-chanteric femoral fractures with the novel helical blade component aimed at limiting femoral head limiting cutout. We demonstrate its use in a variety of cases.

Methods: This is a prospective study of 370 consecutive patients treated with short and long PFNA systems at a single center with 1-year follow-up. The device was used for unstable trochanteric femoral fractures (AO-classification 31. A.2 and A.3), prophylactic and definitive fixation of pathological fractures and high energy femoral fractures for a wide age range (19–101 years). Clinical outcome involved assessment of general mobility & function, operative and post-operative parameters & complications. Radiological outcome involved assessment of blade tip-apex distance, nail tip-femoral scar distance and distal locking configurations.

Results: 17% died within the follow-up period. 72% achieved their pre-trauma mobility status and nearly all fractures healed within 6 months including those in over 85 years. Of 18 problematic cases, serious complications included deep infection, loss of proximal reduction, ipsilateral femoral shaft fracture and periprosthetic supra-condylar fracture. There were no cases of acetabular penetration or blade cut-out. Short PFNA was associated with the majority of femoral shaft fractures and the only significant finding regarding instrumentation.

Discussion: This study supports long PFNA design theory demonstrating adequate purchase in the femoral head-neck zone, shown by lack of cut-out. Positive results have been demonstrated in a variety of cases making it a useful option in fractures in all ages and indications alongside unstable trochanteric configurations.

We treated 63 club feet in 44 patients by a defined programme of strapping from birth followed by one of two operations performed at six weeks, either a simple calcaneal tendon lengthening or a subtalar realignment, and reviewed them prospectively. The decision as to which operation to perform was taken at four weeks after radiographic measurement of the talocalcaneal angle. All but eight patients (ten feet) were followed for a mean of 8.7 years. The overall results after calcaneal tendon lengthening were satisfactory. The re-operation rate after subtalar realignment was high (39%) due to over or undercorrection of the deformity.

Ten patients with Charcot-Marie-Tooth disease have been reviewed at an average of 14 years after soft tissue procedures to correct foot deformities. No patient has so far required triple arthrodesis and the overall results as regards function, appearance and symptoms are satisfactory in all patients. It is concluded that soft tissue procedures can certainly postpone the need for triple arthrodesis and in many cases may obviate it altogether.

Radiolucent lines at the bone-cement interface beneath the tibial components were assessed in 91 consecutive Oxford meniscal knee replacements in 78 patients. Of 80 knees in which radio-opaque cement was used, a radiolucent line was observed in 77, with a radiodense line in the bone immediately adjoining. Radiolucent lines developed in the majority of patients within one year after operation. In 11 knees fixed with radiolucent cement (which precluded assessment of the radiolucent line) a radiodense line was observed beneath the lucent cement in all cases. Histological examination of the interface obtained from secure tibial components showed the lucent zone to be composed of fibrocartilaginous connective tissue and the radiodense line to be a thick lamella of bone. It is suggested that the living bone under a rigid prosthesis requires a layer of relatively compliant fibrocartilaginous material at its interface to accommodate load-bearing. Attention is drawn to the importance of the radiodense line: its presence may constitute positive evidence that healing at the level of bone section is complete and that equilibrium is established; its absence at a mature interface may indicate disequilibrium and impending failure.