Fracture of a ceramic component in total hip replacement.

Fracture of a ceramic component in total hip replacement is a rare but potentially catastrophic complication. The incidence is likely to increase as the use of ceramics becomes more widespread. We describe such a case, which illustrates how inadequate initial management will lead to further morbidity and require additional surgery. We present the case as a warning that fracture of a ceramic component should be revised to another ceramic-on-ceramic articulation in order to minimise the risk of further catastrophic wear.

Outcome of intralesional curettage for low-grade chondrosarcoma of long bones.

BACKGROUND: Different treatment strategies for low-grade chondrosarcomas are reported in the literature with variable outcomes. The aim of this study was to assess the oncological and functional outcomes associated with intralesional curettage and cementation of the lesion as a treatment strategy. PATIENTS AND METHODS: We performed a retrospective review of 39 consecutive patients with intramedullary low-grade chondrosarcoma of long bones treated by intralesional curettage and cementation at our institution between 1999 and 2005. RESULTS: There were 10 males and 29 females with a mean age of 55.5 years (32-82), and a mean follow-up of 5.1 years (3-8.7). Local recurrence occurred in two patients (5%) within the first two years following index surgery. Both were treated by re-curettage and cementation of the resultant defects. A second local recurrence developed a year later in one of these two patients, for which a further curettage followed by local liquid nitrogen treatment was performed. Overall, there were no cases of post-operative complications or metastases. The patients were assessed using the Musculoskeletal Tumour Society scoring system (MSTS) to determine limb function. The average score achieved was 94% (79-100%). CONCLUSION: Intralesional curettage is an effective treatment strategy for low-grade intramedullary chondrosarcoma of long bones, with excellent oncological and functional results. Careful case selection with stringent clinical and radiographic follow-up is recommended.

Chromosomal aberrations in the peripheral blood of patients with metal-on-metal hip bearings.

BACKGROUND: Approximately one-third of patients undergoing joint replacement are under sixty years of age. Many of these patients may be exposed to wear debris from the orthopaedic implant for several decades. Clinical follow-up of this group of patients has been short compared with the lifetimes of the patients, and the long-term effects of this chronic exposure are unknown. METHODS: By using cytogenetic biomarkers (twenty-four-color fluorescent in situ hybridization [FISH]), we analyzed the peripheral blood leukocytes for chromosomal aberrations in three groups of subjects: (1) six age and sex-matched control subjects who had no implant and did not smoke (control group), (2) five subjects in whom an implant with a metal-on-metal articulation had been in situ for an average of thirty-five years (metal-on-metal group), and (3) four subjects in whom a metal-on-metal implant had been revised to a metal-on-polyethylene articulation at an average of twenty-two years (revised group). RESULTS: The number of chromosomal aberrations in the metal-on-metal group was greater than that in the control group. Specifically, the percentage of aneuploidy gain was three times greater (p = 0.01) in the metal-on-metal group. Structural aberrations were not seen in the control group, and this difference was highly significant (p = 0.003). Also, the number of chromosomal aberrations in the metal-on-metal group was greater than that in the revised group. Specifically, the percentage of structural aberrations was thirty-one-fold higher (p = 0.013). The percentage of aneuploidy gain in the metal-on-metal group was about twice that in the revised group, although this difference was not significant (p = 0.37). The percentage of aneuploidy gain in the revised group was about double that in the control group, although this difference was also not significant (p = 0.41). Translocations were seen only in subjects with a metal-on-metal articulation. CONCLUSIONS: The clinical consequences of the chromosomal changes seen in this study are unknown, and it is unknown if the changes are present in other cells in the body. The results emphasize the need for additional investigations into the effect of chronic exposure to elevated levels of metal ions produced by orthopaedic implants.

A study comparing split with loop transverse colostomies for defunctioning the left colon.

BACKGROUND: Loop transverse colostomy (LTC) is an established method for defunctioning the distal colon. We recently described an alternative method called split transverse colostomy (STC). METHODS: In this study we retrospectively compared the outcomes of LTC and STC in 49 patients with colorectal malignancy, pelvic tumours and diverticular disease. RESULTS: Patients were assigned without randomisation to undergo LTC (n=25) or STC (n=24). The two groups were similar in terms of age, gender and diagnosis. Postoperative complications were observed in 52.0% of patients in LTC group and in 16.7% of patients in STC group (p<0.05). The most common complication in both groups was stomal prolapse (n=2 and n=10, respectively). There were no intra-operative deaths. CONCLUSIONS: STC is safe, effective and associated with a lower incidence of stomal complications compared with the established procedure for defunctioning the distal colon. We propose that STC should be used to defunction the left colon in locally advanced disease (whether benign or malignant) where closure of the stoma is not envisaged.

Metal-on-metal joint arthroplasty: potential lifetime longevity.

We have studied a historical group of patients who underwent metal-on-metal hip arthroplasty more than 30 years ago. Those retaining their original metal-on-metal articulation (average follow-up 33 years) had an average Harris Hip Score of 75 (range 53-93) and an average Musculoskeletal Tumour Outcome Score of 75 (range 63-90). Those that have been revised (at an average of 22 years) maintain good functional outcome. The original implant is still in situ in five of the 11 survivors (follow-up 26-38 years). Retrieval analysis using a Mitutoya form tracer and an electron microscope demonstrated the self-polishing capacity of the metal-on-metal articulation. The surface roughness (Ra) of the worn articulating surface (Ra 0.05 mm) was smoother than that of the original unworn surface (Ra 0.32 mm). We believe our case series highlights the potential longevity of metal-on-metal articulation.

Anterior or posterior: does the surgical approach to the hip influence the quality of the femoral cement mantle?

The purpose of this study was to determine whether the surgical approach to the femoral neck during total hip arthroplasty affects the quality of femoral cement mantle in terms of thickness and defects, both of which have been implicated in the development of aseptic loosening. A retrospective radiological review of 50 Stanmore Hip femoral stems inserted using the anterior approach and 50 inserted via the posterior approach was performed, with analysis by zone of cement mantle thickness and number of defects. This study demonstrates that the anterior approach is associated with an increase in the frequency of deficiencies in the cement mantle. We recommend that surgeons using the anterior approach are wary of this increased risk and adopt measures, such as the use of distal centralisers, to minimise its occurrence.

Annular pancreas - a rare cause of gastric obstruction in an 82-year-old patient.

Annular pancreas is an uncommon and rarely reported congenital anomaly and thus is rarely suspected. A case is reported of an 82-year-old patient who presented with a 3-month history of nausea and vomiting associated with weight loss who at laparotomy was found to have an annular pancreas.