The optimal surgical approach for total hip replacement (THR) remains controversial. We report the clinical outcomes of over 1000 patients in the Exeter primary outcomes study (epos) who underwent primary THR with a cemented Exeter stem (Stryker) but with various acetabular components. This was a prospective non randomised multi centre study. Patient reported hip scores (oxford hip score (OHS)) were measured before operation and at 3 months (n= 1312), 1 (n=1276), 2 (n= 1225), 3 (n=1205) and 4 (n=975) years post operatively. Physician reported scores (Merle d’Aubigne / Postel, MDAP) were measured before operation and at 12 months. All of the operations were carried out using either the anterolateral (Hardinge or modification) or posterior approach.

The posterior approach gave better absolute OHS scores at 3 months and 1 year compared with the anterolateral approach. The improvement in OHS between the pre-op and relevant post-op score was better for the posterior than the Hardinge approach, and this extended to 4 years (all p< 0.05). Early dislocation rates were low in both groups. There was significantly more likely to be heterotopic ossification in the Hardinge group, while stem alignment into varus was more common in the posterior approach group. There was no significant difference between the two approaches as measured using the MDAP score at pre-op or at 12 months after surgery.

These results demonstrate that initial patient perceived clinical benefit of surgery is greater using a posterior than with an anterolateral approach. This should be considered when assessing the best approach for a particular patient. The current results emphasise the value of using patient based outcome measures, as the MDAP score did not detect a difference in outcomes between the two groups.

Older fracture patients frequently ask whether their osteoporosis will affect fracture healing. There is only limited previous data about this. We investigated recovery after distal radial fracture, and compared it with BMD of the other distal radius and the lumbar spine (measured using quantitative CT).

All 28 patients had sustained a dorsally displaced distal radial fracture which was deemed to require treatment by intrafocal wire fixation. All patients had acceptable correction of dorsal and radial angle at final x ray (3 months). Wrist function was measured using the Patient Rated Wrist Evaluation (PRWE – a validated outcome measure for use after distal radial fractures), grip strength,and range of motion. All measurements were made at 6, 12 and 26 weeks. BMD was measured in the opposite wrist and the lumbar spine using QCT at 6 weeks after fracture.

There was no correlation between recovery of grip strength (% of contralateral grip strength) at 6,12,or 26 weeks with BMD at either site. Similarly, there was no correlation between BMD and either absolute PRWE scores at any time point or improvement in PRWE between time points. The strongest predictor of recovery of grip appeared to be the proportion of grip recovered at 6 weeks (correlation between% grip recovered at 6 weeks and 3 months r = 0.85; at 6 weeks and 6 months r= 0.56; both p < 0.001). This was not affected by age or variations in measured final dorsal or radial angles or length within this group. It was not affected by degree of preoperative fracture displacement.

These data suggest that recovery of function after distal radial fractures is not influenced by osteoporosis. The data about the importance of initial recovery of grip suggest that factors other than bone position and bone healing may affect rate of functional recovery after distal radial fracture.

There has been controversy about the practice of mixing femoral and acetabular implants from different manufacturers in total hip replacement (THR). We studied the clinical outcomes of over 1500 patients in the Exeter Primary Outcomes Study (EPOS) who underwent primary THR with a cemented Exeter stem (Stryker) but with various acetabular components. This was a prospective non-randomised multicentre study. Patient reported hip scores (Oxford Hip Score (OHS)) were measured before operation and at 1 and 2 years post operatively. The choice of acetabular implant was at the surgeons’ discretion. 982 patients had reached four year follow up. Six types of acetabular component were examined (Exeter, Exeter Contemporary, Duraloc (all Stryker), Charnley (DePuy), Cenator (Corin), and Trilogy (Zimmer)).

Patients who received a Charnley cup were found to have worse pre-operative status (significantly higher OHS) than those receiving other cups (especially those receiving Exeter cups) (p< 0.01). Post operatively, this difference continued, with the absolute OHS value remaining greater (i.e. worse clinical result) for the Charnley cup at 1, 2, 3 and 4 years. The association of poor pre-op status with worse post-op result was anticipated. However, when the clinical benefit of surgery (i.e. the improvement in OHS between pre-op and post-op) was assessed, there was no significant difference between the various implants at 1, 2, 3 and 4 years.

These results demonstrate that initial clinical benefit of surgery does not differ between patients receiving acetabular implants from varying manufacturers when the Exeter stem is used. These patients will be followed further to determine whether such “mixing and matching” results in differences in longer term outcomes.

There has been controversy about whether limb length discrepancy (LLD) affects outcome after total hip replacement (THR). We examined input variables and outcomes of over 1200 patients who received primary THR with the Exeter stem and a variety of acetabular components in the Exeter Primary Outcomes Study. This was a non randomized prospective multi centre study.

We examined whether specific groups of patients or surgeons were more likely to have LLD at one year after surgery. Data for leg length measured on clinical assessment were available for 1207 patients at 1 year. 237 patients were recorded as having a leg length difference of 1 cm or more, and 73 a difference of 2 cm or more. 138 were longer on the operated side and 99 were shorter. The likelihood of having LLD of 2 cm or more was not significantly affected by the grade of surgeon (consultant or trainee), BMI, age of patient, position of patient during surgery or surgical approach, or the use of regional or general anaesthetic.

We examined the effect of LLD on outcomes at 3 months and 1,2,3 and 4 years. Patients with LLD > 1cm had significantly worse Oxford Hip Scores (OHS) at 1, 2, 3 and 4 years (p< 0.01), with the OHS generally being an average 2 points worse in those with LLD. The most consistent difference between those with and without LLD was a patient reported limp on the Oxford Hip Questionnaire.

We conclude that LLD is a common problem after THR and that all patient groups may be affected. It is associated with a significantly worse functional outcome as measured by a validated hip score. Systematic adoption of accurate intra-operative measures of leg length might pay dividends in minimizing this complication.

There is concern that patients undergoing total hip replacement by trainee surgeons may do worse than those operated on by consultants. We examined the clinical outcomes of over patients in the Exeter Primary Outcomes Study who underwent primary THR with a cemented Exeter stem (Stryker) with various acetabular components. Over 1400 patients entered the prospective non-randomised multi centre study. Patient reported hip scores (Oxford Hip Score (OHS)) were measured pre operation and at 3 months, 1,2,3 and 4 years post operatively.

The number of patients assessed at 4 years was 982. Trainees operated on patients with worse pre-operative OHS (p< 0.05; t test)) and on significantly less patients under 60 years (p< 0.05 chi square). There was no significant difference in the improvement in OHS (i.e. pre-op OHS – post-op OHS) at any post-operative time point between consultants and trainees. However, patients operated upon by consultants had consistently better postoperative absolute OHS scores (p< 0.05 at 3 months and 1, 2, 3 and 4 years; t test). Complications were low in both groups. Operations performed by trainees lasted longer (mean of 104 vs. 85 minutes). There was also no difference in OHS scores of patients operated by trainees whether they were assisted by an SHO (n=132) or by a consultant (n=249).

In this large cohort of patients there was no difference in the improvement in OHS between patients operated by registrars and consultants. The difference in the absolute OHS values is likely explained by the difference in pre-operative status. We conclude that THRs performed by consultants and by trainees under appropriate supervision give similar initial clinical results. Given current changes to shorten surgical training, it is important that outcomes of THRs performed by future trainees are reviewed to ensure that outcomes are maintained.

Introduction: In this study infrapatellar fat pad (IPFP) derived stem cells were expanded with and without Fibroblast Growth Factor-2 (FGF-2) supplementation and were compared with regards to their ability to proliferate and differentiate into chondrocytes.

Materials and Methods: Cells were isolated from the IPFP tissue and expanded in monolayer culture with and without rhFGF-2 supplementation (final concentration 10ng/ ml). Cell aggregates were placed in chondrogenic media for two weeks. Gene expression studies were carried out using quantitative real time PCR. Immunohistochemical labelling was performed with antibody localisation determined by an immunoperoxidase procedure. The pellets were also weighed and digested in papain for DNA and glycosoaminoglycan (GAG) analysis.

Results: Cells expanded in FGF-2 supplemented media were smaller and proliferated more rapidly. The FGF-2 supplemented cell aggregates also showed 100 times higher expression of collagen type II (COL2A1). Immunohistochemical studies showed that pellets made from FGF-2 treated cells stained more strongly for collagen II and more weakly for collagen I. Pellets made with FGF-2 treated cells were larger, continued with enhanced proliferation and contained more proteoglycan.

Conclusion: Our findings show enhanced proliferation and chondrogenic differentiation in IPFP derived stem cells expanded in FGF-2 supplemented media.

Aseptic loosening is a growing problem for orthopaedic surgeons and the importance of elevated hydrostatic pressure in its development in vivo is now well documented, but the mechanisms by which pressure could enhance loosening are unclear. We have demonstrated that hydrostatic pressures increased MP synthesis of cytokines, chemokines, PGE2 and M-CSF in vitro, all of which are implicated in bone resorption. 1,25-dihydroxy vitamin D3 (1,25D3) has a pivotal role in bone resorption. It stimulates osteoclastic bone resorption and formation, causes fusion of committed osteoclast precursor cells and activates mature osteoclasts in vitro. Under the correct conditions, macrophages (MP) have the ability to differentiate into osteoclasts. Research has shown that MP can synthesise 1,25D3 and changes in this synthesis occur during MP differentiation. We therefore examined how the application of hydrostatic pressure to MP in vitro influenced their synthesis of 1,25D3. In this study, normal human peripheral blood MP (5x105/ml) were cultured for 7 days then exposed to physiological pressure (34.5x10-3MPa) and/or UHMWPE particles (8mg/ml) and the effect on synthesis of 1,25D3 by endogenous 1a-hydroxylase (1aOHase) was studied. MP were incubated with H3-25, hydroxy vitamin D and 1,25D3 synthesis was analysed by HPLC. 1,25D3 synthesis was increased in cells under pressure by an average of 17% compared to static controls. In situ hybridisation (ISH) was used to demonstrate expression of 1aOHase. Image analysis showed a small increase in 1aOHase mRNA in response to pressure and to particles, and a larger increase to the two stimuli simultaneously. Expressed as % of maximum +Pressure + Particles 100%;+ Particles 59%; +Pressure 37%; No Stimulus < 0.1%. These results suggest that 1,25D3 may be one of the factors which stimulates osteoclastic bone resorption in aseptic loosening. As both these stimuli are likely to be present in vivo, such synthesis could further exacerbate loosening.

Mechanical load is crucial to maintaining skeletal homeostasis, but the pathways involved in mecha-notransduction are still unclear. The OPG/RANK/ RANKL triumvirate has recently been implicated in bone homeostasis. These molecules, which are produced by the osteoblast (OPG and RANKL) and the macrophage/osteoclast (RANK), modulate osteoclastogenesis. We have previously shown that cyclical hydrostatic pressure influenced synthesis of various molecules by cultured human macrophages. These factors are important in osteoclastogenesis and bone resorption and have been linked to the development of aseptic loosening. We have also demonstrated that 1,25-dihydroxyvitamin D3 (1,25D3) influences macrophage response to pressure. For this study human macrophages were co-cultured with osteoblasts and subjected to cyclical hydrostatic pressure (34.5x10–3MPa [5.0 psi]) for up to five days, with or without 1,25D3 supplementation. Cells were immunostained for RANK and culture media were assayed for sRANKL and OPG using specific ELISAs. Immunostaining for RANK showed that macrophages subjected to pressure or 1,25D3 supplementation synthesised more RANK than controls. In addition, when exogenous 1,25D3 and hydrostatic pressure were administered simultaneously, immunostaining for RANK was more intense. There was a reciprocal relationship between OPG and sRANKL in co-cultures subjected to pressure. If pressure increased synthesis of sRANKL, OPG was decreased. In cultures where pressure decreased sRANKL, a corresponding increase in OPG was seen. In addition, samples from different individuals responded differently to pressure. The majority of cell populations responded to pressure by increasing OPG synthesis, compared to non-pressurised controls. These results demonstrate for the first time that the OPG/RANK/RANKL complex is sensitive to hydrostatic pressure and that 1,25-dihydroxyvitamin D3 might be involved in this response. These findings suggest a possible transduction mechanism for mechanical load in the skeleton, which has implications for future therapies for aseptic loosening and for skeletal abnormalities such as osteoporosis.

This paper describes the surgical indications and technique for lateral femoral cutaneous neurectomy in the hip following formation of a neuroma post surgery.

We would like to present a single surgeon series of the treatment of localised trochanteric pain post total hip replacement. It is believed that in certain cases localised pain in the line of the scar is attributable to formation of a neuroma of the posterior branch of the lateral femoral cutaneous nerve of the thigh.

Method We have reviewed a consecutive series of 5 patients who underwent this procedure for unremitting pain following THR. Of the 5 patients 4 underwent unilateral neurectomy and one underwent a bilateral neurectomy. All had persistent pain before the operation with a positive Tinnel’s test.

Results Of all the patients, 4 said that their pain was improved after the operation and would undergo the operation again. One had no improvement at all. None were worse after the operation.

Conclusion We believe selective neurectomy to be a good procedure in this often, difficult clinical situation.

Several case reports will highlight the findings on history and examination and the technique used.

Cross match practice for patients with femoral neck fractures continue to cause concern due to a failure of compliance to the existing protocols. We addressed this issue by conducting a number of studies over three years and we report the summation of the studies and demonstrate the reasons for the poor compliance. We provide a simple and effective protocol that has helped reduce preoperative cross matching of femoral neck fractures from 71% to 16.7% two years after its introduction.

Study 1

Retrospective review of the cross-match practice for 240 femoral neck fractures and reviewed the changes in pre-operative and post-operative haemoglobin levels and association with surgical procedure.

Study 2.

Postal questionnaire of 129 anaesthetic and orthopaedic trainees assessing the perceived cross-match requirements of patients with femoral neck fractures based on preoperative haemoglobin values between 8–13g/dl. In addition reviewed the source of trainees perceptions and practice

Study 3

Review of the efficiency of the cross-match protocol two years after its introduction Results

Study 1

71% patients with femoral neck fractures were cross-matched at admission but only 29% of the patients were subsequently transfused. From the 384 units of blood ordered at admission 230 were returned unused. Inter-trochanteric fractures had a mean blood loss of 3.1g/dl (range 1.5–7.2g/dl) following surgery in comparison to a mean loss of 1.7g/dl (0.9–3.4g/dl) for patients with displaced subcapital fractures

Study 2

Orthopaedic trainees at all levels of training requested more blood then their anaesthetic counterparts for patients with femoral neck fractures. There was misconceptions regarding blood loss following surgery amongst all trainees and only 14.3% trainees used existing literature to guide their cross-match practice where as 53.4% devised protocols based on their own or colleagues’ experience.

Study 3

Cross-match protocol was working effectively. Only 16.7% of the patients with femoral neck fractures were cross-matched on admission.

Conclusion

Cross-match recommendations fail to influence trainees. In order to address this we produced a protocol that does not rely on orthopaedic trainees. The haematology MLSO provides the appropriate amount of preoperative blood for the patient based on our finding of blood loss of different fracture patterns and the patients’ preoperative haemoglobin level. Our results show our protocol is still effective two years following its introduction despite numerous changes in trainees during this period.

The role of MRI or CT in the management of patients with LBP, for whom there is no clear clinical indication for the use of sophisticated imaging, is uncertain. The aim of The Scottish Back Trial was to determine whether early use of MRI or CT influences clinical management and outcome of patients with LBP and whether it is cost-effective.

Elective patients were new referrals to orthopaedic or neurosurgeons with symptomatic lumbar spine disorders (without ‘red flags’). After obtaining informed consent, patients were randomised to ‘early imaging’ (imaging as soon as practicable) or ‘delayed, selective imaging’ (imaging only if an imperative clinical indication developed). Principal outcomes measures were the SF-36, questionnaire, the Aberdeen LBP Scale and the EQ-5D. Patients completed questionnaires at trial entry and after 8 and 24 months.

From 15 hospitals, 2657 patients were assessed and 783 were recruited and randomised. Eight months and twenty-four months after trial entry, comparison of data abstracted from case notes indicated that, apart from the use of imaging, both groups had received similar clinical management. At follow-up, an improvement in health status, as measured by the SF-36 and Aberdeen LBP Scale, was reported by both groups. At 24 months, there was a statistically significant but small difference in favour of the ‘early imaging’ group (p=0. 002) as measured by the Aberdeen LBP Scale but no difference in the SF-36 except a marginal improvement in the bodily pain subscale.

The use of MRI or CT imaging for this group of LBP patients did not significantly affect their management. The clinical significance of the marginal improvement in health status in the ‘early imaging’ group is uncertain. The results of the cost-effectiveness analysis may clarify whether a policy of ‘early imaging’ would be a cost effective use of resources.

Introduction: Collagen type X is secreted by hypertrophic chondrocytes during fracture repair. Its precise role is uncertain. This study uses a knockout mouse model in which the collagen X gene is removed to examine its function.

Method: Bilateral femoral fractures were created in type X collagen knockout mice (mutant) and normal mice (wild type), and were stabilized using an external fixator. The mice were sacrificed 7, 10, 14, 21, 28 and 60 days after fracture. Fracture healing was followed by x-rays, histology, gene expression studies, immuno-histochemistry and mechanical testing.

Results: In the mutant mice, bony union was delayed, there was abnormal persistence of aggrecan up to 60 days after fracture. Histology reviewed amorphous acellular areas surrounded by osteoclasts at 21 and 28 days, while mechanical testing revealed that at 14 days after fracture, mutant callus was stiffer than the wild type, but the trend is reversed at 28 and 60 days.

Discussion: This study contributes to the understanding of the basic mechanisms involved in fracture repair. The data suggest that collagen type X plays a significant role in bone remodeling during fracture healing. Its absence results in delayed union and abnormalities within the fracture callus.

Infection of the intervertebral space is a rare complication of operation on the disc (Ford and Key 1955). It occurred in five cases in a series of 650 operations for lumbar disc protrusion done by two of the authors of this paper--an incidence of 0-8%. Symptoms began between seven and twelve days after operation. After initial relief of the original sciatic pain, the patients developed severe back pain and muscle cramps in the legs. Straight-leg raising became much more limited than before operation. The erythrocyte sedimentation rate was raised in all cases. The diagnosis was confirmed by rescreening the Myodil, when an indentation was seen opposite the intervertebral space from which the disc had been excised. Early removal of infected material from the disc space resulted in complete relief of pain and cure of the infection.