Aim

Cementless prosthesis is one of the major bone-implant interface fixation methods in total joint replacement. Grit blasted surface, hydroxyapatite coated surface and plasma sprayed metallic porous coating have been popularly used. The latter has demonstrated higher bone implant mechanical stability in previous laboratory study in early and middle stages. However, question remains what the mechanism is to make it performing better and how to improve them further. This study is designed to examine the mode of failure in bone-implant interface in a sheep model.

This study was performed to compare the mechanism of bone-implant integration and mechanical stability among three popularly used cementless implant surfaces. Plasma sprayed porous surface (TiPL), grit-blasted rough surface (TiGB), and hydroxyapatite coated implant surface (HA) were tested in a sheep model at 4 and 12 weeks. The integration patterns were investigated using histology, histomorphometry, and mechanical strength by push-out test. All three groups demonstrated early bone ongrowth on their surfaces, with much of the ongrowth resembling contact osteogenesis. TiPL group showed bone anchorage into porous coating with new bone ingrowth into the pores. HA group revealed small cracks at its coating at 12 weeks time point. Plasma sprayed porous surface also demonstrated its superior mechanical stability maybe reinforced by its bone anchorage, whearas, HA surface exhibited higher osteoconductivity with highest ongrowth rate.

Animal studies examining tendon-bone healing have demonstrated that the overall structure, composition, and organization of direct type entheses are not regenerated following repair. We examined the effect of Low-Intensity Pulsed Ultrasound (LIPUS) on tendon-bone healing. LIPUS may accelerate and augment the tendon-bone healing process through alteration of critical molecular expressions.

Eight skeletally mature wethers, randomly allocated to either control group (n=4) or LIPUS group (n=4), underwent rotator cuff surgery following injury to the infraspinatus tendon. All animals were sacrificed 28 days post surgery to allow examination of early effects of LIPUS. Humeral head – infraspinatus tendon constructs were harvested and processed for histology and immunohistochemical staining for BMP2, Smad4, VEGF and RUNX2. All the growth factors were semiquantitative evaluated. T-tests were used to examine differences which were considered significant at p < 0.05. Levene's Test (p < 0.05) was used to confirm variance homogeneity of the populations.

The surgery and LIPUS treatment were well tolerated by all animals. Placement of LIPUS sensor did not unsettle the animals. Histologic appearance at the tendon-bone interface in LIPUS treated group demonstrated general improvement in appearance compared to controls. Generally a thicker region of newly formed woven bone, morphologically resembling trabecular bone, was noted at the tendon-bone interface in the LIPUS-treated group compared to the controls. Structurally, treatment group also showed evidence of a mature interface between tendon and bone as indicated by alignment of collagen fibres as visualized under polarized light. Immunohistochemistry revealed an increase in the protein expression patterns of VEGF (p = 0.038), RUNX2 (p = 0.02) and Smad4 (p = 0.05) in the treatment group. There was no statistical difference found in the expression patterns of BMP2. VEGF was positively stained within osteoblasts in newly formed bone, endothelial cells and some fibroblasts at the interface and focally within fibroblasts around the newly formed vessels. Expression patterns of RUNX2 were similar to that of BMP-2; the staining was noted in active fibroblasts found at the interface as well as in osteoblast-like cells and osteoprogenitor cells. Immunostaining of Smad4 was present in all cell types at the healing interface.

The results of this study indicate that LIPUS may aid in tendon to bone healing process in patients who have undergone rotator cuff repair. This treatment may also be beneficial following other types of reconstructive surgeries involving the tendon-bone interface.

The transosseous equivalent/Suture Bridge or TOE/SB repair has received much attention in recent years as more shoulder surgeons transition to all arthroscopic rotator cuff repairs. The purpose of this study was to compare the biomechanical behaviour of several variants of the Suture Bridge repair performed by the authors.

Four different Suture Bridge constructs were performed six times on 24 sheep infraspinatus tendon humerus constructs. The first group was a standard Suture Bridge with two medial mattress stitches with knots (KSSB4). The second group had four medial mattress stitches with knots and was called KDSB8. The third group had two medial mattress stitches without knots and was called USBFT4. These first three repairs used two medial 5.5 mm Bio-Corkscrew FT Anchors and two lateral 3.5 mm PushLock Anchors (Arthrex). The fourth repair had two medial mattress stitches without knots and used all Pushlocks and was called USBP4.

The repairs were then analysed for failure force, cyclic creep and stiffnessafter. Cycling was performed from 10 to 100 N at 1 Hz for 500 cycles. Following cyclic testing a single cycle pull to failure at 33 mm/sec was performed. The constructs were also observed for failure mechanism and gap formation using digital video recording.

The KDSB8 repair with a mean failure force of 456.9N was significantly stronger than the USBP4 repair at 299.7N (P=0.023), the KSSB4 repair at 295.4N (P=0.019) and lastly the USBFT4 repair at 284.0N (P=0.011). There was no statistical difference between the measured failure force for the two mattress stitch KSSB4 repair with knots and the knotless two mattress stitch repairs USBFT4 and USBP4. There was not a statistical difference between any of the repairs for measured stiffness and cyclic creep. However, the KDSB8 repair showed no discernable gap formation or movement at the footprint during cyclic testing. The KSSB4, USBFT4 and USBP4 repairs demonstrated bursal sided gap formation in the range of 1 to 3 mm.

Based on the results of this study the transosseous equivalent/Suture Bridge repair with four stitches tied in the medial row and maximal lateral suture strand utilization (KDSB8 TOE/SB) is the strongest. The KDSB8 also appeared to show less bursal sided gap formation and greater footprint stability than the other Suture Bridge constructs tested.

NICE published the guidelines ‘Selection of prostheses for primary hip replacement’ in 2000. Essentially these guidelines made two recommendations: firstly to use prostheses which had attained the ‘10 year benchmark’ of a revision rate of 10% or less at 10 years, or had a minimum of three years revision rate experience that was on target to reach this benchmark; and secondly to use cemented hip prostheses to the exclusion of uncemented and hybrid prostheses.

The information from the Trent Regional Arthroplasty Study (TRAS) has been used to retrospectively examine the types of hip prostheses used from 1990 – 2005, and assess the impact that the NICE guidelines have had on orthopaedic practice.

This study revealed that the percentage of prostheses used which attained the ‘ten year benchmark’ has increased since the guidelines were published. In 2001, of the ten cups, which constituted 80% of the acetabular components used, only three attained this NICE benchmark, but by 2005 this number had risen to eight. Similarly in 2001, of the eight stems, which constituted almost 80% of the femoral components used, only five attained this NICE benchmark. In 2005 seven out of these eight stems had attained the minimum standard.

However contrary to the recommendation made by NICE in 2000, to use cemented prostheses, the results indicate the use of uncemented prostheses has trebled (from 6.7% to 19.2%, n= 137 and 632 respectively), and the use of hybrid prostheses has more than doubled (from 8.8% to 22% of all prostheses, n= 181 and 722 respectively) since the guidelines were published.

Therefore the recommendations made by NICE are not being followed, which calls the value of NICE guidelines into question.

Background: Musculo-skeletal conditions account for at least 10% of General Practice consultations yet the average time spent by UK medical students in orthopaedic and trauma surgery is only 2.7 weeks.

Aim: This study assessed whether a seven-week undergraduate musculoskeletal teaching program introduced in 2006 improved performance.

Methods: This seven week program combined Orthopaedic and Trauma Surgery with Rheumatology and allied specialities. Its main elements were weekly plenary sessions, specialist clinics, a task-based workbook, regular assessments and traditional firm based teaching. The performance of 139 students who attended the new curriculum in its first year of introduction was assessed using multiple choice questions just before their final examinations in 2008 and was compared to that of a control group of students assessed in 2005 prior to program introduction.

Results: The 2008 students showed a 6% improvement in MCQ scores (p< 0.001) over the 2005 graduates. There was no difference between the 2005 students and a second control group of 46 students from 2008, who did not attend the new teaching program.

Conclusion: The program improved performance by providing more focused musculoskeletal training using available resources and by increasing the program duration.

The literature is filled with reports of various studies identifying perioperative factors that adversely affect survival. The aim of this study was to identify perioperative factors associated with an increased risk of death at 5 years.

All patients admitted to our unit in 2002 with a proximal femoral fracture were included. Demographic details, physiological parameters and biochemical parameters on admission were documented. Survival data at five years was available for all patients and was used to perform survival analyses. 633 patients with a proximal femoral fracture were admitted to our unit between January 2002 to December 2002. Data for all patients was available for analysis. There were 118 men and 515 women, M:F =1:1.4. Average age of the patients was 81.2±9.4 years (range 45–105 years).

Univariate analysis showed that patient age, mental test score, number of days delayed to surgery, number of comorbidities, ASA grade, if the patient lived in an institution, had a previous stroke, suffered from congestive cardiac failure or valvular heart disease, heart rate, serum haemoglobin, serum urea and whether the patient developed a post operative complication were all significant factors that affected survival. Multivariate analysis showed that mental test score (Exp B=0.939 95%CI=0.901–0.978 p= 0.002), age (Exp B = 1.031 95%CI= 1.004–1.058 p= 0.025) and ASA grade (Exp B = 1.458 95%CI= 1.039–2.046 p= 0.029) were all independent variables that affected five year survival.

Various independent factors affect five year survival in patients with proximal femoral fracture. It is important that these factors are identified firstly, so that patients and relatives can be given information about survival and secondly, so that high risk patient groups can be allocated adequate resources in order that their peri and postoperative care is optimised. This may improve outcome in these subgroups of patients.

It is has been suggested that as a result of the skewed age distribution, the incidence of hip fracture will increase disproportionately among Asians. The epidemiology of hip fracture among the Asian and White populations in Leicestershire the five year survival between the two groups was investigated.

All patients in Leicestershire with hip fracture between 2001–2 were studied. Demographic data, type of fracture, and treatment was recorded. Ethnic origin was noted as White, Asian, or other. Survival at 5 years was documented as number of days survived. The results were analysed statistically.

On thousand one hundred and thirty-four patients were admitted to our unit with hip fracture, 617 intracapsular fractures and 517 extracapsular fractures. Leicestershire Census data in 2002 showed that 85.7% of the population was white, 11.9% Asian and the remaining 2.4% of other ethnic group. The percentage of Asians > 65 years was 8.8% compared to 18.9% of whites. The number of Asian patients < 65 years with a hip fracture was significantly greater than the number of whites < 65 years (p =0.002, Fishers exact test). Five year survival of Asian patients < 65 years with hip fracture was significantly lower than white counterparts in the same age group (p = 0.002)

Over the last decade there has been a 30% increase in the Asian population in Leicestershire (9.3% to 11.9%). The proportion of Asians over 65 years doubled over the last decade from 4.3% to 8.8%. The proportion of Whites over 65 years increased from 16.3% to 18.9%. The 5 year survival of Asians with hip fracture under 65 years old is significantly reduced when compared to Whites. This suggests that Asians under the age of 65 years that sustain hip fracture may have other risk factors that may contribute to their earlier demise.

The aim of this study was to evaluate temporal trends in the prevalence of primary total hip and knee replacements (THR and TKR) throughout the Trent region from 1991 through 2004.

The Trent Regional Arthroplasty Study (TRAS) records details of primary THR and TKR prospectively. TRAS data in conjunction with age-gender population data from the National Office of Statistics was used to quantify the rates of primary THR and TKR as a function of age (45–55, 56–65, 66–75, 76–85 and greater than 85 years), gender and diagnosis (osteoarthritis, rheumatoid arthritis and trauma). Poisson regression analysis was used to evaluate the procedural rate over time in primary THR and TKR as a function of age, gender and diagnosis.

A total of 26,281 THR and 23,606 TKR were recorded during this period. The overall prevalence for primary THR did not change significantly over time (IRR = 1.0, 95% CI: 0.99 to 1.0, p = 0.875), whereas, the overall prevalence for primary TKR increased significantly by 2.5% during the fourteen year period (IRR = 1.025, 95% CI: 1.021 to 1.028, p < 0.001). Analysis showed that females had an increased incidence rate ratio (IRR) for both primary THR (IRR = 1.29, 95% CI: 1.26 to 1.33, p < 0.001) and TKR (IRR = 1.17, 95% CI: 1.14 to 1.20, p < 0.001). Patients aged 74–85 years had the largest IRR for both primary THR (IRR = 6.7, 95% CI: 6.4 to 7.0, p < 0.001) and TKR (IRR = 15.3, 95% CI: 14.4 to 16.3, p < 0.001).

The prevalence of primary TKR increased significantly over time whereas THR increased steadily in the Trent region between 1991 and 2004. These trends have important ramifications to the number of joint replacements expected to be performed in the future.

Introduction: The proximal femur is the most common long bone to be affected by metastatic disease. The prognosis of patients with bone metastases is variable and depends on a number of factors. Risk factors affecting survival in this subgroup of patients need to be clearly determined.

Patients and Methods: We studied the survival of 32 consecutive patients with metastatic disease of the proximal femur in order to identify any clinical, radiological or physiological parameters that predict survival.

Results: Mean age of patients was 71 years (range 41–91 SE 2.2) and mean survival 393 days (95 % CI 236 to 550), cumulative survival at three years was 0.12. Univariate analysis showed that sex, serum haemoglobin < 10gm/dl, white cell count > 12, serum urea and the presence of a postoperative complication were all significant predictors of survival. However, multivariate analysis revealed that only sex, serum haemoglobin < 10 gm/dl, white cell count > 12 and a postoperative complication were independent risk factors predicting survival (p < 0.05).

Discussion: Perioperative factors should be optimised for all patients. Identification of risk factors adversely affecting survival can be used in conjunction with clinical and radiological information as a tool to predict outcome and to aid consenting and counselling of patients. Simple measures such as preoperative transfusion of blood or the administration of blood products may improve survival. The presence of an elevated white cell count may indicate more advanced systemic disease. Aggressive postoperative rehabilitation and the prevention of complications may also improve survival.

Introduction: A cosmetic deformity does not always occur after a biceps tenotomy. The anatomical restraints preventing distal excursion of the long head of biceps tendon following tenotomy have not previously been described. This study aims to evaluate the biceps sheath and its potential role as a restraint to distal excursion of the biceps following tenotomy.

Methods: Fifteen fresh cadaveric specimens were dissected free of overlying soft tissues to reveal the rotator cuff, biceps sheath and long head of biceps muscle belly and tendon. Eight specimens were used for gross anatomical analysis. Measurements of the length of the biceps sheath on the humeral (bone) side and tendon side were made using a digital caliper (Mitutoyo, Japan). The long head of biceps tendon was then released from the glenoid labrum and the excursion of the stump relative to the rim of the articular surface measured. The biceps sheaths of two specimens were used for histological analysis.

Seven specimens were used for mechanical analysis. A humeral osteotomy was performed distal to the insertion of pectoralis major, leaving intact the biceps sheath and the muscle belly of long head of biceps. The proximal humerus was attached to a custom-designed jig and the muscle belly of biceps grasped in cryogenic grips. Specimens were loaded on an MTS 858 Bionix mechanical testing machine (MTS Systems, MN) in uniaxial tension at a rate of 1 mm/sec until failure was observed.

Results: The biceps sheath surrounds the long head of biceps tendon and inserts into the bone of the proximal humerus. It is trapezoidal in cross-section, with a mean length of 75.1 mm on the bone side and 49.3 mm on the tendon side. The average excursion of the stump was to within 2.8 mm of the rim of the articular surface.

Histological examination of the biceps sheath revealed membranous tissue consisting of loose soft tissue with fat and blood vessels. Synovial tissue was also identified. The sheath was seen to loosely attach to the biceps tendon, with a more intimate attachment to the periosteum.

The mean force to pull the long head of biceps tendon out of the sheath 102.7 N (range 17.4 N–227.6 N)

Discussion: The biceps sheath is a consistent structure intimately associated with the biceps tendon. It appears to contain blood vessels which provide nutrition to the tendon, similar to the vincula of flexor digitorum pro-fundus. Mechanical testing reveals that a substantial force is sometimes required to pull the biceps tendon from the sheath. This may explain why biceps tenotomy does not routinely result in a “Popeye” biceps.

Purpose: To evaluate the fifteen year survivorship of primary Total Knee Replacements in a single UK health region.

Methods: Since the beginning of 1990, and with the agreement of all consultant orthopaedic surgeons in the region, all primary total knee replacements (TKR) performed throughout Trent were recorded prospectively. At the time of operation the surgeon completes a questionnaire, which records demographic, medical and operative details for each patient and implant.

In this study we have traced all the patients, who had a primary total knee replacement between 1990 and 1992. We issued a validated, self administered questionnaire to all surviving patients, at a mean of fifteen years post arthroplasty. This questionnaire examines the patient’s level of expectation and satisfaction with their TKR, and also measures their quality of life (using EQ-5D and visual analogue score). Using a similar register, containing information of all revision TKR in the region, we have measured the survivorship of these primary TKR at 10 and 15 years.

Results: 4,665 primary TKR were performed on 4,448 patients. At fifteen year follow-up 1,408 patients were alive. The questionnaire response rate was 57.1% (n=912). Of our responders, 87.8% were satisfied with the result of their TKR at 15 years post-arthroplasty, and 82% felt their TKR had met their expectations.

Survivorship analysis revealed that 94.7% (+/−0.4%) of implants survive to 10 years, and 92.7% (+/−0.5%) to 15 years. Survivorship was significantly affected by gender of the patient, age at time of primary, and type of prosthesis used. Infection rate at 15 years was 0.9%.

Discussion: This is one of the first long term studies of primary TKR, which assesses survivorship of primary TKR beyond 10 years. This study shows that survivorship at 5 and 10 years compares favourably to the results of similar studies from other countries.

Approximately 10% of primary hip replacements performed each year for osteoarthritis are in patients aged 55 or less. These patients have a longer life expectancy and a higher activity level than an elder cohort, which may translate to higher revision rates.

We utilized a regional hip register (Trent and Welsh Arthroplasty Audit Group (TWAAG)) to review current surgical practice in this age group. The TWAAG group comprises 118 surgeons working in 31 different hospitals covering a population of 8 million (14.2% of the population).

1 January 2000 to 31 December 2002, we were notified of 7,678 primary THRs for osteoarthritis. 911 (11.7%) were performed on patients aged 55 or less. Age, gender, grade of lead operating surgeon, type of femoral and acetabular prosthesis implanted, fixation method, femoral head size and bearing surfaces were recorded. There were 434 males, 477 females, with an age range of 16–55. Thirty-five femoral and thirty-three acetabular components were identified. 61.7% of femoral prostheses were cemented. 67.4 % of acetabular prostheses were uncemented. 30% of THRs implanted in the group over the study period were hybrid. 50% of implants had a metal/UHMWPE bearing. Other bearing surfaces comprised ceramic/UHMWPE 28.7%, metal/ metal resurfacing 13.8% and ceramic/ceramic 7.5%. Consultants performed 84.5% of procedures.

Femoral prostheses with little or no published data are used and, unless closely monitored, such practices will not be compliant with NICE recommendations. 40% of THRs performed had components implanted that were produced by different manufacturers. At the present time there does not appear to be a clear picture as to what is the ‘gold’ standard for young patients. Continued monitoring of these implants is essential to provide feedback and drive choice.

The Trent Arthroplasty Audit Group has been prospectively collecting data on primary hip and knee arthroplasties since 1990. Details of 61,000 primary and 4,00 revision arthroplasties have been registered. The Royal College of Surgeons of England. Capital Hip Report (July 2001) concluded that a national joint register could have detected failures of an implant at an earlier stage. We examined data on the register to ascertain why we had been unable highlight a problem with this implant.

The Trent Arthroplasty Register was unable to detect the poor results with Capital hips at an earlier stage than surgeons. A scientific presentation had raised concern before our register could detect a problem. The hips had been listed for revision but were still on a waiting list. Additionally some of the failed hips were not revised as patients were insufficiently fit for surgery.

The stated reason for revision on revision forms was vague and not sufficient to draw conclusions as to the mechanism of failure. Radiological studies have identified a higher radiological failure rate than expected (Charnley & Elite +) but we have shown that outcome scores (Oxford Scores) were not successful at identifying these failures. Since the implementation of the Data Protection Act (1998) consent must be obtained before details are registered, which may lead to further inaccuracy in the creation of survivorship curves.

Joint registers can contain the problem once it is detected but are not a substitute for regular follow-up. Surgical vigilance and a scientific approach is required to ascertain the reason for failure. Revision should not be the only endpoint for registration. Joint registers may be part of the solution but need to be backed up with adequate resources, financial and intellectual, to analyse clinical information, if valid conclusions are to be drawn.

This meta-analysis supports the conclusion that in patients with recurrent traumatic anterior shoulder instability, an open repair has a more favorable outcome with respect to recurrence and return to activity when compared to arthroscopic repair. More evidence from randomized clinical trials is required to either refute or substantiate this conclusion.

The purpose of this study was to evaluate the outcomes between arthroscopic and open repair for recurrent traumatic anterior shoulder instability.

The search involved clinical studies of all languages in the Medline database up to October 31, 2001. The following key words were used:

anterior shoulder instability;

All abstracts were reviewed and articles were included if there was a direct comparison between arthroscopic and open repair for traumatic recurrent anterior shoulder instability. These articles were manually assessed and cross-referenced for additional abstracts. The final group of articles were independently critically appraised and data on recurrent instability and return to activity (RTA) was extracted.

Recurrent instability was defined as patient report of one or more subluxations and/or dislocations. RTA was not consistently defined in these articles and was based upon the available information.

584,

From these searches, sixteen articles were determined eligible for the meta-analysis including two foreign and two unpublished manuscripts. Ten studies were included in the final analysis: one RCT, two pseudo-experimental designs, four prospective cohorts, and three retrospective studies.

Pooled Mantel-Haenszel Odds Ratio for recurrent instability and RTA were 2.22 (p=0.002, 95%CI 1.36,3.65) and 2.85 (p=0.004, 95%CI 1.40,5.78) respectively, in favor of the open repair.

Based upon this meta-analysis open repair has a more favorable outcome with respect to recurrence and RTA.

We sought to determine the incidence of complications and re-operation up to one year following primary total knee replacement in a single health region.

The Trent Arthroplasty Audit group collects prospective data on all knee replacements performed within this health region (population 5.2 million). All patients are sent a validated, self-administered questionnaire one year after surgery. The questionnaire addresses patient satisfaction and any complications and re-operations following surgery. We analysed the returned questionnaires of 5352 patients [5896 knees] who had their primary knee arthroplasty between 1998 to 2000. Responses were received from 4169 patients [4592 knees] (response rate 80%). Clinical records were also examined to gain further information.

516 patients reported complications in 546 knees. Complication rate of (12%) and 3.5% had a further operation on the joint within one year. Complications were highest following knee replacement for trauma (36%) followed by osteoarthritis (12%) and lowest for rheumatoid arthritis (8%). We have no knowledge of the complexity of the surgery but 60% of the complications occurred in patients operated on by a Consultant, 29% by a Specialist Registrar and 10% by an Associate Specialist & Staff Grade. On the whole Consultants performing fewer than 10 joint replacements per year registered a higher complication rate (21%) as compared to Consultants performing more than 25 joints per year (12%), but they performed 18% of the arthroplasties. The incidence of complications, as stated by the patient was as follows: Pain 7%, Stiffness 2%, Superficial infection 1%, Swelling 0.7%, Deep infection 0.7%, DVT 0.4%. 1.2% (infection 0.4%: Instability 0.7%: Patellar resurfacing 0.2%), Manipulation (1.3%), Arthroscopy (0.7%), ORlF of Peri-prosthetic fracture (0.06%). 12 % of the patients who had a primary knee replacement in Trent region between 1998 and 2000 considered that they had a complication. Complications rates appear to be higher for surgeons performing less than 10 joint replacements per year. Only 43% of Consultants performed more than 10 knee arthroplasties themselves in any one of these three years. The deep infection rate was 0.4% and one-year post surgery the revision rate, for all causes was 1.2% and the manipulation rate was 1.3%.

The Trent Arthroplasty Audit Group has been prospectively collecting data on primary knee arthroplasty since 1990 and revision procedures since 1992. Details of 27 000 primary and 1300 revision knee arthroplasties have been registered. In 2001 hospitals in Wales joined the group, increasing the catchment population to 8 million (14% of the UK population). The register has enabled evaluation of changes in the demography and surgical practice of knee arthroplasty in the Trent region over the past 13 years.

Over this period there has been a steady increase in the number of arthroplasties registered, from 1330 cases in 1990 to 2855 in 2002. Whilst there has been a slight increase in the proportion of men undergoing surgery, the age distribution remains consistent (mean age 69 years). PFC/Sigma is currently the most commonly used prosthesis in the region.

Since 1990 the number of patients registered with rheumatoid arthritis has fallen by almost 50%. During this period there has also been a slight decrease in the proportion of uncemented joints and a decline in the number of bilateral simultaneous procedures taking place.

The ratio of primary to revision knee arthroplasty has not changed significantly since 1992 but there is some evidence of specialisation of revision knee surgery. There has been no significant change in patient satisfaction rates since the start of the registry, with 80% of patients reporting that they are satisfied with their joint replacement at 1 year.

Conclusion: It is reasonable to assume that these findings reflect practice across the UK as a whole, given the diversity of hospitals contributing and the large population base of the Trent & Wales register.

Cerebral micro emboli have been noted to occur during both total hip and knee arthroplasty. These micro emboli have been implicated in the causation of postoperative cognitive impairment. The aim of this study was to determine whether cerebral micro emboli occur during hip fracture surgery.

28 patients undergoing hip fracture surgery had transcranial doppler assessment of the middle cerebral artery to detect cerebral micro emboli. Micro embolic signals (MESs) were recorded during the operative procedure.

Successful monitoring was carried out in 26 patients. MES were recorded in 16 out of 26 patients. 12 out of 16 patients who had MESs had undergone a cemented hemiarthroplasty; the remainder had a sliding hip screw for an extracapsular hip fracture. 75% (9/12) of patients who had a cemented hemiarthroplasty had the majority of MESs after reaming and cementing. MESs in the patients who had a sliding hip screw occurred throughout the operative procedure.

Conclusion: Cerebral micro emboli do occur during hip fracture surgery. These emboli may be responsible for the cognitive dysfunction that occurs in this susceptible group of patients.

We matched 78 patients with a loose cemented Charnley Elite Plus total hip replacement (THR) by age, gender, race, prosthesis and time from surgery with 49 patients with a well-fixed stable hip replacement, to determine if poor bone quality predisposes to loosening. Clinical, radiological, biomechanical and bone mineral density indicators of bone quality were assessed.

Patients with loose replacements had more pain, were more likely to have presented with atrophic arthritis and to have a history of fragility fracture, narrower femoral cortices and lower peri-prosthetic or lumbar spine bone mineral density (all t-test, p < 0.01). They also tended to be smokers (chi-squared test, p = 0.08). Vitamin-D deficiency was common, but not significantly different between the two groups (t-test, p = 0.31)

In this series of cemented hip replacements performed between 1994 and 1998, aseptic loosening was associated with poor bone quality. Patients with a THR should be screened for osteoporosis and have regular radiological surveillance.

Introduction The 2002 NCEPOD report recommended that autopsies should be the subject of a formal external audit process. It is thought that a post mortem would improve the understanding of the pathological events leading up to the death of a patient. The aims of this study were to find out the number of post mortems requested for patients with hip fracture and to establish the cause of death of all hip fracture patients as documented on the death certificate by medical practitioners and the coroner.

Patients and Methods A retrospective review of all hip fracture deaths in the year 2000 was performed. The number of cases referred to the coroner for a post mortem and the given verdict was documented. Data regarding the cause of death (as per part 1a on the death certificate) recorded by the medical practitioner and the coroner was established.

Results 83 patients with a hip fracture died in hospital in 2000 (mean age 83.6 years, range 58–97 years). There were 30 male and 53 female deaths. 37 patients (44.6%) were referred to the coroner for a post mortem examination. The common causes of death documented by the medical practitioner were: Bronchopneumonia; 27.9%, Congestive cardiac failure; 11.6%, Left ventricular failure; 9.3%, Cerebrovascular accident; 14%, and Carcinomatosis; 4.6%. The common causes of death documented by the coroner were: Bronchopneumonia; 35.1%, Congestive cardiac failure; 16.2%, Left ventricular failure; 10.8%, Cerebrovascular accident; 2.7%, carcinomatosis; 8.1%, and Pulmonary embolism; 8.1%.

Conclusion Approximately 45% of hip fracture deaths are referred to the coroner. Apart from PE, the cause of death documented by medical practitioners and the coroner was no different in terms of frequency and spectrum. Cardiac and respiratory causes account for nearly 2/3 of hospital hip fracture deaths. Resources need to be targeted accordingly in an attempt to improve in hospital morbidity and mortality.

Introduction and Aims: To assess the 10-year outcome of knee arthroplasty surgery in a generalist setting, across a single UK health region.

Method: The Trent Arthroplasy Audit Group has been collecting prospective data on primary knee replacements since 1990. 4677 primary knee replacements were performed in the period 1990–92. A validated self-administered questionnaire, including a EuroQol health evaluation questionnaire, was mailed to all surviving patients. The mean age at the time of surgery was 70 years.

Results: Thirty-nine percent of the patients had died by 10 years. Responses were received from 87% of patients. Eighty-two percent of patients had been satisfied with the result of their knee replacement. Twenty-one percent of patients felt that it was not as good as they had been led to believe before surgery. Forty percent of patients had had problems with their knee in the 10 years since surgery. Twenty-one percent had had some form of surgical intervention. Eighty-two percent of patients were taking medication to alleviate pain in their replaced knee.

Eighteen percent complained of constant pain in this knee. When the pain occurred it was described as being severe in 16% and moderate in 40%. Most patients were on prescribed medication, but had not been referred to a surgeon to identify if there was a problem with their implant. The revision rate, for all causes at 10 years was 13%.

Conclusion: The results of knee arthroplasty at 10 years are disappointing. Patients’ responses indicate that previously successful knees are becoming painful. At the present time there appears to be inadequate long-term follow-up/re-referral of patients and surgeons have a high threshold for revision surgery. More detailed clinical examination is planned for this group of patients.

Introduction and Aims: Cerebral micro emboli have been noted to occur during both total hip and knee arthroplasty. These micro emboli have been implicated in the causation of post-operative cognitive impairment. The aim of this study was to determine whether cerebral micro emboli occur during hip fracture surgery.

Method: Twenty-eight patients undergoing hip fracture surgery had transcranial doppler assessment of the middle cerebral artery to detect cerebral micro emboli. Micro embolic signals (MESs) were recorded during the operative procedure.

Results: Successful monitoring was carried out in 26 patients. MES were recorded in 16 out of 26 patients. Twelve out of 16 patients who had MESs had undergone a cemented hemiarthroplasty, the remainder had a sliding hip screw for an extracapsular hip fracture. Seventy-five percent (9/12) of patients that had a cemented hemiarthroplasty, had the majority of MESs after reaming and cementing. MESs in the patients that had a sliding hip screw occurred throughout the operative procedure.

Conclusion: Cerebral micro emboli do occur during hip fracture surgery. These emboli may be responsible for the cognitive dysfunction that occurs in this susceptible group of patients.

Introduction and Aims: To audit the practice and evaluate the outcomes of knee arthroplasty surgery in a general setting in the UK.

Method: The Trent & Wales Arthroplasty Audit group collects prospective data on all knee replacements performed within these UK health regions (population eight million). All patients are sent a validated, self-administered questionnaire to assess outcomes. Data has been collected on 27,500 primary and 1400 revision knee procedures.

Results: In the period from 1990 to 2002 there has been a marked decrease in the proportion of knees being replaced for rheumatoid arthritis (21% to 5%). More arthroplasties are being performed in men (35% to 46%). There has been an increase in knee arthroplasty in patients aged 85+ yrs (2.1% to 3.7%), but a decrease in patients aged 55yrs and under (8.6% to 5.3%). Uncemented implants are used less frequently (7.7% to 4.4%). Unicompartmental knee are implanted more frequently (2.8% to 4.1%). In 2002, 10% of the joints implanted had mobile bearings, 8% were PCL sacrificing, 28% had the patella resurfaced, 0.4% were patellofemoral replacements.

The percentage of patients satisfied with their arthroplasty one-year post-surgery has not improved over the 13 years. (O.A 81%, R.A 87.5% , trauma 63%). The incidence of reoperation (for all causes) in the first year is 1.2% (0.5% infection). The incidence of revision for implant failure appears to be increasing. Outcome data for revision surgery is being collected at present.

Conclusion: Over the past 13 years there has been a marked increase in knee arthroplasty surgery and significant demographic trends. However, validated outcome measures have not shown an improvement of outcome over this period.

The Trent Arthroplasty Audit Group (TAAG) has been prospectively collecting data on primary knee arthroplasty since 1990 and revision procedures since 1992. To date details of 27 000 primary and 1300 revision knee arthroplasties, from both teaching and district general hospitals in the Trent region, have been contributed.

This provides us with a unique opportunity to look at the outcome of total knee arthroplasty across an English region, at 10 or more years of follow-up.

A questionnaire was designed, with assistance from the department of epidemiology and public health, including both generic (EuroQol) and knee specific questions. Patients who underwent primary knee arthroplasty from 1990–92 were included in the study (4420 patients). Surviving patients (65%) were traced using the NHSIA patient tracing service and the questionnaire was administered by post with a response rate was 55%.

The mean length of follow-up was 11 years 7 months and the mean age at the time of follow-up was 78 years. The vast majority (86%) of patients were satisfied with their joint replacement. Although 52 % took prescribed analgesia for pain in their knee, 22% still complained of pain often or all the time. 18% felt their knee totally or greatly interfered with their usual activities. 14% of patients reported re-operation on their knee, of which 11% were revision procedures.

This suggests that a significant number of patients experience pain and/or disability at 10 or more years following knee replacement. Since most GPs have a high threshold for re-referral in this group of patients, it is likely that the degree of morbidity has previously been underestimated in the orthopaedic community.

Introduction: Estimates suggest that 50% of new cases of invasive cancer diagnosed each year will eventually metastasise to bone. The proximal end of the femur is the most common site of long bone involvement by metastatic disease. Accepted principles for the treatment of metastatic disease of the proximal femur have been published. The results of 31 consecutive patients treated with a long intramedullary hip screw for metastatic disease of the proximal femur are reported.

Patients and Methods: Retrospective case note review of all patients that had a long intramedullary hip screw for metastatic disease affecting the proximal femur over a four-year period 1998–2002.

Results: The case notes of 31 patients (33 femurs) were reviewed. There were 21 females and 12 males with a mean age of 71 years. 31 femurs were Zickel group Ia or Ib, the remaining 2 were impending pathological fractures (Zickel group II) that were fixed prophylactically.

Post operatively all patients were allowed to fully weight bear. 70 % of patients regained their initial level of mobility or increased their level of dependence by a factor of one. Mean hospital stay was 20.8 days (mode 7 days). Patients that died post operatively had a mean survival of 299 days (range 2–1034). Those patients that were still alive at the last follow up had a mean survival of 475 days (range 7–1384). There were no cases of fixation or implant failure. There was one case of deep infection that was treated by implant removal.

Conclusion: On the basis of these findings, the long intramedullary hip screw fulfils the principles for treatment of metastatic disease and can be recommended for the treatment of pathological or impending pathological fractures of the proximal femur.

Purpose: To determine the incidence of complications and re-operation up to one year following primary total knee replacement in a single health region.

Methods: The Trent Arthroplasty Audit group collects prospective data on all knee replacements performed within this health region (population 5.2 million). All patients are sent a validated self-administered questionnaire one year after surgery. The questionnaire addresses patient satisfaction and any complications and re-operations following surgery. We analysed the returned questionnaires of patients who had their arthroplasty in the years 1998 to 2000. Responses were received from 4317 patients (response rate 75%). Clinical records were also examined to obtain additional information.

Results: Patients reported complications in 516 knees (500 patients). Complication rate (12%). We have no knowledge of the complexity of the surgery but 60% of the complications occurred in patients operated on by a Consultant, 29% by a Specialist Registrar and 10% by an Associate Specialist/ Staff Grade. 2.2% (125 patients) of the patients died within one year of their arthroplasty. The incidence of complications, as stated by the patient was as follows:

Complication: Pain 7%,Stiffness 2%,Superficial infection 1%, Swelling 0.7%, Deep infection 0.7%, DVT 0.4%.

Re-operation / Revision Surgery: Revision: 1.2% (infection 0.5%: Instability 0.7%: Patellar resurfacing 0.4%), Manipulation (1.3%), Arthroscopy (0.7%), ORIF of Periprosthetic # (0.06%).

Conclusion: 12 % of the patients who had a primary knee replacement in Trent region between 1998 and 2000 considered that they had a complication. The deep infection rate was 0.5% and one-year post surgery the revision rate, for all causes was 1.2%. The Manipulation rate was 1.3%.

Background: The majority of extracapsular proximal femoral fractures are treated with a sliding hip screw. The barrel of the plate can slide over the shaft of the screw in two modes; keyed (locked) or unkeyed (unlocked). The purpose of the study was to determine whether there is a difference in outcome following þxation using a sliding hip screw in the locked and unlocked modes.

Methods: A prospective randomised controlled trial of patients requiring a sliding hip screw for a proximal femoral fracture. Patients were randomised to receive a sliding hip screw either in the locked or unlocked mode. 20 patients were randomised to each group. Patients were assessed clinically and radiologically post-operatively and at three months following discharge from hospital. Screw slide and þxation failure were used as primary outcomes. A Visual analogue scoring system (VAS) was used to assess pain.

Results: 40 patients were recruited in this study. Mean age of patients in the locked group was 74.05 years (range 55–90) and 78.0 years (range 65–97) in the unlocked group. There was one case of þxation failure in the locked group compared to two in the unlocked group. The mean screw slide was 10.98mm (range 1.04–37.62) in the locked group and 12.94mm (range 1.91–20.82) in the unlocked group. The pain score according to the VAS improved over the three months. There was no signiþcant difference in pain score between the two groups.

Conclusion:When comparing screw slide, þxation failure and pain, the results show there is no signiþcant difference between using the sliding hip screw in the locked and unlocked mode.

The National Institute for Clinical Excellence (NICE), in its “Guidance on the Selection of Prostheses for Primary Total Hip Replacement”, states that a revision rate of 10% or less at ten years should be regarded as the “benchmark” in the selection of prostheses for primary Total Hip Replacement (THR). This paper presents the results of such a study for primary Charnley THR. Methods: All patients undergoing primary Charnley THR during 1990 were prospectively registered with the Trent Regional Arthroplasty Study (TRAS). During 1990, 1198 Charnley THRs were performed on 1152 patients, under the care of 56 consultants, in 18 National Health Service and 6 private hospitals. The cohort contains 39.0% male and 61.0% female patients, with an average age at operation of 69.1years (21–103 years), 19.1% being less than 60 years. At 10 years all surviving patients at 5 years were registered with the ONS to ascertain living patients. These patients were contacted by letter to determine whether or not their THR had been revised. The status of the THR, for non-responding patients, was determined by contacting the patient’s GP through the Contractor Services Agency (CSA). The endpoint was defined as revision surgery to replace an original implant component. Results: At 10 years, the recipients of 438 THRs had died. The recipients of 89 THRs did not respond to the questionnaire at ten years. Implant status at ten years, in living patients was known for 671 of 760 (88.3%) THRs. The ten-year crude revision rate was 44 out of 1198 (3.7%) and cumulative survival rate was 95.5% (95% CI, 93.6% – 96.9%).

Conclusion: This is the first study to assess the survivorship at 10 years for primary Charnley THRs performed in the ‘general setting’ of the NHS as opposed to specialist centres and shows a result well within the NICE benchmark.

The aims of the study were to determine the prevalence of post thrombotic syndrome following lower limb arthroplasty in patients who did not receive chemical thromboprophylaxis, and identify morbidity associated with the condition. From the Trent regional arthroplasty database patients 5 years post elective total knee or hip replacement were identified. All patients were under the care of two senior orthopaedic consultants who performed surveillance venography between the 7th and 10th postoperative day. Prophylaxis for DVT was in the form of below knee compression stockings. Above knee DVTs were anticoagulated, below knee compression stockings was administered for below knee DVT.

Two doctors conducted a clinical review in the manner suggested by the American Venous Forum Executive Committee. Clinical examination was used to assess the presence and class of post-thrombotic syndrome. 71 patients were reviewed. With respect to the ipsilateral limb, there were 32 patients with a DVT and 39 without DVT. Six classes excluding normal, class 0, are used to describe the clinical findings. 17 (24%) patients had no visible sign of venous disease (class 0). 14 (20%) patients suffered minor venous disease (class 1). 28 (39%) patients had established varicose veins (class 2). 2 (3%) patients had oedema without skin changes (class 3). 8 (11%) patients had skin changes ascribed to venous disease ie. pigmentation, venous eczema, lipodermato-sclerosis (class 4). 2 (3%) patient had skin changes as defined with healed ulceration. No patient had skin changes as defined previously with active ulceration (class 6).

Minor venous disease (classes 1 & 2) is common and seen in 44% of DVT negative and 78% of DVT positive patients in this study. Severe venous (classes 3,4 & 5) disease is uncommon and seen in 20% of DVT negative and 13% of DVT positive patients in the study. Symptomatic patients were equally distributed between DVT positive and negative groups. Severe venous disease was more common in the DVT negative group. Concluding, minor venous disease is common post lower limb arthroplasty, severe disease occurred in 17% of patients and appeared unrelated to a previous DVT. The presence of a DVT does not influence the development of skin changes of post-thrombotic limb.

To assess primary and revision knee arthroplasty revision activity in a single English health region, and identify trends and reasons for revision surgery.

Surgeons performing knee arthroplasty surgery in Trent Region (Population 5.13 million: 16 hospitals : 107 Consultant Orthopaedic Surgeons) provide the Trent Arthroplasty Audit Group with patient and operative details by completing a standard proforma. Data capture is optimised by a peripatetic clerk checking theatre and admission records in each hospital

18762 primary knee arthroplasties were performed in Trent Region in the period 1990 – 1999.

949 revision knee arthroplasties were performed between 1992 and 1999.

In the last 10 years the number of TKA’s implanted in patients aged 55 yrs or less increased by 300%, there was a corresponding increase of 380% in patients aged 85 yrs. or over whilst the number of patients who had their knee replaced for rheumatoid arthritis decreased by 59%. 83% of patients are satisfied with their TKA when questioned 1 year post surgery. 52 of the 87 surgeons who perform TKA revision perform less than 1 per year whilst 30% of the revisions are performed by 4 surgeons in this region. The reasons for revision TKA were:

5% of knees revised for infection required further revision surgery for recurrence of the infection.

The Trent Knee Arthroplasty Register has the potential to help us evaluate TKA outcome and set standards in a U.K. settting.

Introduction: The National Institute for Clinical Excellence (NICE), in its “Guidance on the Selection of Prostheses for Primary Total Hip Replacement”, states that a revision rate of 10% or less at ten years should be regarded as the “benchmark” in the selection of prostheses for primary Total Hip Replacement (THR). Furthermore, they state that evidence for this, in relation to a particular prosthesis, should relate to data from a number of centres, obtained via adequately sized, well conducted observational studies, preferably with consecutive patients from non selected populations. Aim: This paper presents the results of such a study for primary Charnley THR. Methods: All patients undergoing primary Charnley THR during 1990 where prospectively registered with the Trent Regional Arthroplasty Study (TRAS). During 1990, 1198 Charnley THRs were performed on 1152 patients, under the care of 56 consultants, in 18 national health service and 6 private hospitals. The cohort contains 39.0 % male and 61.0 % female patients, with an average age at operation of 69.1years (21–103 years). At 10 years all surviving patients at 5 years were registered with the ONS to ascertain living patients. These patients were contacted by letter to determine whether or not their THR had been revised. The status of the THR, for non-responding patients, was determined by contacting the patient’s GP through the Contractor Services Agency (CSA). Survival analysis was performed using life table analysis as described by Armitage and Berry and the endpoint was defined as revision surgery to replace an original implant component. Results: At 10 years, the recipients of 246 THRs had died. The recipients of 86 THRs did not respond to the questionnaire at ten years. There was no follow–up data on 42 implants at both 5 and 10 years intervals. Thus, implant status at five or ten years, in living patients was known for 910 of 952 (95.6%) THRs. The ten-year crude revision rate was 43 out of 1198 (3.59%) and cumulative survival rate was 95.4% (95% CI, 93.2% – 96.9%). Conclusion: This is the first study to assess the survivorship at 10 years for primary Charnley THRs performed in the “general setting“ of the NHS as opposed to specialist centres and shows a result well within the NICE benchmark.

Aim: To define the contact force and contact area at the glenoid labrum-bone interface between suture sites in an open transosseous Bankart repair, and to assess how these contact parameters are altered by tying adjacent sutures to each other.

Methods: Twelve capsulolabral avulsion lesions were created in fresh-frozen human shoulder specimens and were repaired using a standard transosseous suture technique. The contact forces and contact areas were measured at the labrum-bone interface between sutures before and after repair. Using the free suture ends, either a single or double strand knot was then tied between adjacent suture sites and the contact parameters were measured again.

Results: The contact forces and contact areas under the soft tissue bridges between transosseous sutures were mildly increased during repair (before repair: average force=5.53g, area=2.25mm²; after repair: force=11.7g, area=3.13mm²). However, both the contact forces and areas increased significantly when a single or double strand of suture was tied over the soft tissue bridge. The double strand technique resulted in a significantly greater increase in contact forces and areas than the single strand technique (single strand average force=70.1g, area=6.75mm²; double strand average force=95.15g, area=8.0mm² p< 0.05).

Conclusions: The contact parameters between labrum and bone in a Bankart repair were increased when the suture strands from adjacent transosseous repair sites were linked. Increasing contact force or contact area may improve healing at the bone-soft tissue interface, and may reduce the risk of “spot welding” repairs. This, in turn, may reduce the failure rate of Bankart repairs.

Introduction: Arthrodesis of the shoulder joint is appropriate for several conditions, including paralysis, degenerative disease, infection, and salvage of failed arthroplasty. Two common complications of shoulder fusion, non-union and unacceptable arm position, may reflect failure to achieve rigid fixation during the surgical procedure. Numerous fixation techniques have been described, including plate fixation, external fixation, and screw fixation.

Aim: To compare the biomechanics of five fixation techniques of shoulder fusion in a human cadaveric model.

Methods: Twenty-five shoulder fusions were carried out in fresh-frozen human cadaveric specimens with the following five techniques: screw fixation alone (n=5), external fixation alone (n=5), external fixation supplemented with screw fixation (n=5), single plate fixation (n=5), and double plate fixation (n=5). Each specimen was tested on a servo-hydraulic machine under repeated physiologic loads to determine the bending and torsional stiffness.

Results: There was a statistically significant difference in bending and torsional stiffness between all five fixation techniques (ANOVA, p< 0.05). Normalised bending (B) and torsional (T) stiffness, in descending order, were: double plate (B=1.0, T=1.0), single plate (B=0.77, T=0.89), external-fixation with screws (B=0.68, T=0.74), external-fixation alone (B=0.40, T=0.53), and screws alone (B=0.13, T=0.26).

Discussion & Conclusion: Statistically significant differences in bending and torsional stiffness have been identified using five different techniques of shoulder fusion. The risk of the most common complications of this surgical procedure, non-union and unacceptable arm position, may be minimised if these biomechanical findings are applied to surgical decision-making.

We performed single-photon-emission CT (SPECT) and planar bone scans to assess femoral head vascularity in ten patients with displaced intracapsular hip fracture. The heads were labelled with tetracycline and after excision at hemiarthroplasty were assessed for tetracycline uptake distribution by fluorescence under UV light. The four which had the greatest tetracycline uptake were normal on SPECT and planar imaging. In two cases the planar bone scans were normal although SPECT suggested avascularity thus giving false-negative results. Surgeons should be aware of this; SPECT may prove to be a more accurate method of assessing vascularity of the femoral head in fractures of the femoral neck.

We report a randomised prospective trial of the early results of three types of treatment for displaced intracapsular hip fractures. We used a questionnaire sent to patients at about six months (Nottingham Health Profile, NHP) in addition to clinical assessments. There was a 67.4% usable response to the questionnaire, similar to that in other studies using the NHP. There were more responders from younger patients, those walking independently before injury and those with higher mental test scores on admission. In the younger group (65 to 79 years) we found a trend for better scores in most NHP indices after the use of a bipolar prosthesis rather than a unipolar prosthesis or internal fixation, particularly for social function, pain and physical mobility. Postal assessment using the NHP gave a satisfactory response rate even in the elderly, and can provide an extra assessment to complement or replace hospital follow-up in some circumstances.

We report the results of a randomised trial to determine the effects of skin traction on 252 patients awaiting surgery for fractures of the proximal femur. They were allocated randomly to be nursed free in bed or to receive Hamilton-Russell skin traction. No differences were found between the groups in terms of pain suffered, analgesia required, frequency of pressure sores or ease of operation. The application of skin traction to patients with fractures of the upper femur is time-consuming and we recommend therefore that its routine use should be discontinued.

We studied the changes in plasma viscosity and C-reactive protein to establish normal values after total hip or knee arthroplasty. Viscosity decreased from 1.68 (+/- 0.017) to 1.57 (+/- 0.014) on the first postoperative day and thereafter rose to 1.60 (+/- 0.019), 1.75 (+/- 0.015), and 1.74 (+/- 0.011) on the third, seventh and fourteenth days respectively. Six to eight weeks after operation it had returned to pre-operative levels. A viscosity above the upper limit of the laboratory range, obtained more than two months after operation, may be considered as abnormal. The C-reactive protein level increased significantly on the first postoperative day and then decreased from a peak on the second day, attaining nearly normal levels at six to eight weeks after operation. It may be a more sensitive indicator of deep postoperative infection than plasma viscosity.

We measured pressures in the anterior and deep posterior compartments continuously for up to 72 hours in 20 patients with closed fractures of the tibial shaft treated primarily in plaster casts. All were examined independently after periods of three to 14 months. Pressures above 40 mmHg occurred in seven (35%) and above 30 mmHg in 14 (70%). No patient had the symptoms of compartment syndrome during monitoring. Abnormalities at review did not correlate with the maximum consecutive time periods during which the compartment pressures were raised. Thus, in the absence of symptoms the monitored pressures did not relate to outcome. Routine monitoring in this type of patient is therefore of doubtful benefit.

We studied 50 patients with fractures of the femoral neck, 33 intracapsular and 17 extracapsular. Intraosseous pressure was measured by a transducer within the bone to quantify blood flow, and intracapsular pressure by a needle introduced into the joint space. The mean intracapsular pressure was lower in the extracapsular fractures. In these, the mean intraosseous pressure in the femoral head was unchanged by aspiration of the joint. However in the intracapsular fractures aspiration produced a significant decrease in intra-osseous pressure and an increase in pulse pressure within the femoral head. The results suggest that aspiration of intracapsular haematoma produced an increase in femoral head blood flow by relieving tamponade.