Patellofemoral joint arthroplasty: patient selection,surgical technique and outcomes

Isolated patellofemoral arthritis is an increasingly recognized entity, and is usually associated with previous patellofemoral dysplasia or instability. Patellofemoral arthroplasty (PFA) has evolved significantly in recent years, both in terms of implant design and importantly in the understanding of appropriate patient selection. This review outlines the indications and investigations for PFA, provides a brief history of the development of contemporary implants, and presents the clinical outcomes for the prostheses most commonly used in the UK. In addition, it provides a detailed surgical technique for implantation of an onlay implant, with tips on how to optimize patellofemoral biomechanics and thus achieve a consistently good outcome.     

Correction of juvenile hallux valgus deformity associated with metatarsus primus adductus using epiphysiodesis technique

A 4.5-year follow-up retrospective study on the use of epiphysiodesis procedure for juvenile hallux valgus deformity and metatarsus primus adductus deformity shows a good reduction of deformity in nine patients with minimal change in one patient that can be explained due to the timing of the procedure. This is a minor operation for juvenile bunion deformities, using epiphyseal arrest techniques. The only complication to this procedure was one case with a noted metatarsus primus elevatus due to incomplete epiphyseal arrest from dorsal to plantar. This procedure has been found to be a safe and effective way of dealing with juvenile hallux valgus deformity when metatarsus primus adductus is the deforming force. It should be stated that in all cases a follow-up biomechanical examination and casting for orthotics took place and to date no complications, other than what has been previously mentioned, has occurred. I shall continue to perform this procedure where indicated and shall report my findings as they become available.     

Complement levels before and after dives with a high risk of DCS.

BACKGROUND: Previously, complement activation has been associated with decompression sickness (DCS). However data, both in humans and in animals, are controversial. Hypothesis: Complement activation and depletion occurs after exposure to the hyperbaric environment and is associated with increasing risk of DCS. METHODS: We obtained serological samples from 102 dives (120-300 feet of seawater) with a constant partial pressure of O2 set at 1.3 ATA in thirty-five U.S. Navy diver volunteers. Blood was obtained within one hour of diving and within one hour of surfacing. Plasma was extracted and analyzed for complement depletion. The risk of DCS was estimated using a validated model of DCS risk. RESULTS: Pre-post dive concentrations of C3a were significantly related to estimated risk of DCS (Figure 1), but the variation in predicted DCS explained by C3a was small (correlation co-efficient (r2 = 0.19, p < 0.0001). CONCLUSIONS: There was a reduction in total Ca3 levels in divers after exposure to dives with a high estimated risk of DCS. This decomplementation appeared to increase as the estimated risk of DCS increased.