While computed tomography (CT) provides an accurate measure of osteolysis volume, it would be advantageous in general clinical practice if plain radiographs could be used to monitor osteolysis. This study determined the ability of plain radiographs to detect the presence of and determine the progression in size of osteolytic lesions around cementless acetabular components.

Nineteen acetabular components were diagnosed with osteolysis using a high-resolution multi-slice CT scanner with metal artefact suppression. Mean duration since arthroplasty was 14 years (range 10–15 years) at initial CT. Repeat CT scans were undertaken over a five year period to determine osteolysis progression. On anteroposterior pelvis (AP) radiographs and oblique radiographs of the acetabulum seen on the rolled lateral hip view, which were taken at the same time as the CT scans, area of osteolysis was measured manually correcting for magnification.

Osteolysis was detected on the AP radiographs in 8 of 19 hips (42%), on the oblique radiographs in 6 of 19 hips (32%) and on the combined AP and oblique radiographs in 8 of 19 hips (42%). Throughout the study period, osteolysis was detected on 31 of 76 AP radiographs (41%) and 22 of 75 oblique radiographs (29%). Osteolysis was more likely to be detected on plain radiographs if the lesion volume was greater than 10cm3 in size (p=0.005). On CT, osteolysis progressed by more than 1cm3/yr in 10 of 19 hips (55%). In these ten hips, osteolysis progression was detected on AP radiographs in six hips and on oblique radiographs in three hips. No correlation was found between osteolysis progression measured by CT and that measured on AP (r2=0.16, p=0.37) or oblique (r2=0.37, p=0.15) or AP and oblique radiographs (r2=0.34, p=0.17).

Plain radiographs are poor in monitoring progression in size of periacetabular osteolytic lesions. Plain radiographs may detect lesions more than 10cm3 in size, but are unreliable.

Computed tomography (CT) provides a sensitive and accurate measure of periacetabular osteolytic lesion volume, however, there may remain a role for plain radiographs in monitoring osteolysis. This study aimed to compare CT and plain radiographs for determining the progression in size of osteolytic lesions around cementless acetabular components.

A high-resolution multi-slice CT scanner with metal artefact suppression was used to determine the volume and progression of osteolysis around 19 cementless Harris Galante-1 and PCA acetabular components. The mean duration since arthroplasty was 14 years (range 10–15 years) at initial CT. Repeat scans of the hip were undertaken over a five year period to determine the progression in size of osteolytic lesions over time. A second blinded observer manually measured the area of osteolytic lesions off anteroposterior pelvis radiographs and oblique radiographs of the acetabulum that were taken at the same time as the CT scan.

All 19 hips had CT detected osteolysis. Osteolysis was detected on one or both of the anteroposterior pelvis or oblique radiographs from at least one time point in eight of 19 hips (42%). Osteolysis was detected on 31 of 76 anteroposterior pelvis radiographs (41%) and on 22 of 75 oblique radiographs (29%) (p=0.140). Osteolysis was more likely to be detected on plain radiographs if the lesion volume was greater than 10cm3 in size compared to those 5–10cm3 and less than 5cm3 in size (p=0.009). In 10 of 19 hips (55%), CT determined that osteolytic lesions progressed in size by more than 1cm3/yr. The mean volume of osteolysis progression was 3.2cm3/yr (range 1.1–7.5cm3/yr). Progression in size of osteolytic lesions was significantly associated with hips with larger osteolytic lesions at the initial CT (p=0.0004). Radiographic measurements detected progression of osteolytic lesions in 5 of the 10 hips (50%) that progressed. No correlation was found between progression in size of osteolytic lesions as measured by CT and progression in size of osteolytic lesions as measured off the anteroposterior pelvis (r2 = 0.16, p=0.37), oblique (r2=0.37, p=0.15) and combined anteroposterior pelvis and oblique radiographs (r2=0.34, p=0.17).

Periacetabular osteolytic lesions are more likely to be detected on plain radiographs if they are more than 10cm3 in size. Plain radiographs may therefore provide some monitoring value as lesions more than 10cm3 are more likely to be progressive. However, plain radiographs should not be relied upon to monitor the progression of these lesions.

Aim: Since 1994, we have used virtually identical criteria to the Swedish Lumbar Spine Study Group before accepting patients for instrumented posterolateral spinal fusion. We review these criteria and the surgical outcome and compare them with those of the SLSSG. Method: 26 patients underwent posterolateral lumbar spinal fusion with Moss-Miami instrumentation between 1994 and 2001 for intractable LBP. Patients selected for surgery had to meet strict inclusion criteria. These were: severe intractable LBP causing significant work or recreational disability which failed to respond to all reasonable non-operative measures; absence of leg pain; no spondylolisthesis or spondylolysis; no neurological signs; no claudication; no other pathology i.e. mechanical/discogenic LBP only; no disc protrusion on MRI; no clinical evidence of learnt illness behaviour; L5/S1 or L4/L5 black discs on MRI, and no black discs above these levels; no litigation or compensation claim in process. Patients were assessed at a minimum of 1 year (range 14–95 months) using the NASS lumbar spine follow-up form, and postoperative radiographs to assess the fusion mass. Results: There were no deaths or significant complications of surgery. 84% of patients showed substantial improvement, 16% were improved but with significant residual pain. None were unchanged or worse. Fusion rate was 92%. Only two patients would not have undergone the same procedure again. Conclusion: We believe that these criteria form a sound basis for selecting patients with severe intractable LBP who might benefit from a posterolateral fusion.

Aims: To establish whether the Ôidealñ concentric positioning of acetabular components within the acetabular cement mantle is achieved during routine cemented total hip arthroplasty.

In vitro studies recommend concentric placement of the acetabular component. There are however no in vitro studies on acetabular component positioning.

Methods: Radiographs of 100 primary cemented total hip replacements were studied. Acetabular component positioning and cement mantles were assessed with respect to implant type, grade of surgeon and operated side.

Results: 78% of the components were eccentrically placed, with increasing cement mantle thickness from zones 1 to 3. Concentricity occurred in only 13% of the Charnley Ogee, and 28% of the IP Lubinus components. The Charnley Ogee was more superiorly eccentric than the IP Lubinus (p< 0.001). The IP Lubinus was generally more open than the Charnley Ogee and Stanmore (p=0.053). Surgical grade affected neither cement mantle nor opening angle.

Conclusions: This study indicates that the ideal component position in the acetabulum is very difþcult to achieve consistently in most patients, using the two commonly used cemented prostheses in this study. The practical difþculty of concentric component positioning while obtaining simultaneous pressurisation is illustrated.

Aim: To assess the efficiency of pre-emptive analgesia in a clinical setting as opposed to closely controlled animal models, looking at postoperative pain scores, total analgesia requirement and amount of general anaesthetic agent required during surgery.

Methods and Results. Subject to exclusions, 40 patients undergoing day-case arthroscopy of the knee (mean age 44 years, ASA grade 1–2) were randomized into two treatment groups. All patients had general anaesthesia. The trial group received an injection of 15mI 0.5% Bupivicaine / 1/200,000 adrenaline pre-emptively. After surgery a placebo injection was given of 15ml normal saline in an identical manner. The control group received the opposite order. Additional post-operative analgesia, if required, was administered in recovery. This was recorded, also total dose of propofol used, time to awakening, visual analogue pain score at 15 / 30 / 60 minutes, postoperative nausea and vomiting at 30 minutes and the number of delayed discharges. Although no difference was observed in postoperative pain scores at 15, 30 or 60 minutes, a trend for the trial group to require less analgesia in recovery was observed (Chi squared =9.74, p=0. 1) but this was not statistically significant.

There was no difference in mean dose of propofol used in either group, 15mg/kg/hr (sd=2.85) trial versus 14.6mg/kg/hr (sd=1.96) control.

Conclusion: Local anaesthetic given pre-emptively appears to be no more effective at controlling pain in the immediate postoperative period than the current standard practice of postoperative injection. It’s effect in clinical practice may be less dramatic than that observed in more controlled animal models and a larger study may be required to show a statistically significant difference.