We studied 50 patients before and after unilateral total hip replacement, and compared them, using gait analysis, with 22 having staged bilateral operations. The average age of the patients was 65 years at the first operation. The mean follow-up was 53 months for the unilateral cases and 27 months, after the second THR, for the bilateral cases. The average interval between first and second THR was 24 months. Patients with bilateral hip disease did not gain optimal function, even on the first side, until both hips had been replaced. Unilateral replacement gave better gait analysis results than did either side after bilateral procedures

We studied the safety of combining the postoperative use of a non-steroidal anti-inflammatory drug with low-dose heparin. In a double-blind, placebo-controlled clinical trial we reviewed the complications in 235 patients after total hip replacement, all treated with low-dose heparin and either indomethacin or a placebo. The incidence and type of complications in the two groups were nearly equal; indomethacin-treated patients had no increase in complications related to bleeding. Postoperative bleeding into drains was marginally greater in the indomethacin group, although the difference was not statistically significant. We conclude that treatment with indomethacin and low-dose heparin after hip replacement does not significantly increase the bleeding or other complications. We also found that patients receiving indomethacin were mobilised an average of one day before those on placebo

Improved cementing techniques have been shown to decrease the rate of aseptic loosening of femoral components of cemented total hip replacements at five to seven years. We now report our results in 105 hips in 93 patients at 10 to 12.7 years (mean 11.2). The improved techniques included use of a medullary plug, a cement gun, a doughy mix of Simplex P and a collared stem of chrome cobalt. Only three femoral components had definitely loosened, none were probably loose and 24 were graded as possibly loose. In contrast, the incidence of radiographic loosening on the acetabular side was 42%. Improved cementing techniques have produced a marked reduction in the rate of aseptic loosening of the femoral component, but the incidence of acetabular loosening is unchanged

At a minimum of one year after operation, we studied 64 patients with 86 total hip arthroplasties (THA) by standard anteroposterior hip and pelvic radiographs and measurement of range of motion and of isometric abduction strength. The femoral offset correlated positively with the range of abduction (p = 0.046). Abduction strength correlated positively with both femoral offset (p = 0.0001) and the length of the abductor lever arm (p = 0.005). Using multiple regression, abduction strength correlated with height (p = 0.017), gender (p = 0.0005), range of flexion (p = 0.047) and the abductor lever arm (p = 0.060). Our findings suggest that greater femoral offset after THA allows both an increased range of abduction and greater abductor strength

We performed a randomised controlled study to compare heparin with the A-V Impulse System in the prevention of deep-vein thrombosis (DVT) in 132 consecutive patients undergoing total hip replacement. After the operation, all patients had compression stockings, 65 were treated with calcium heparin and 67 with the intermittent plantar pump. DVT was diagnosed by Doppler ultrasound and thermography, followed by phlebography. There were 23 cases of DVT (35.4%) in the heparin group, with 16 major and seven minor thromboses. In the impulse pump group there were nine cases (13.4%) with three major and six minor thromboses. The differences for all thromboses and for major thromboses were both significant at p < 0.005. In the heparin group there was one fatal pulmonary embolism and nine patients (13.8%) had excessive bleeding or wound haematomas, as against none in the impulse pump group

We made a prospective study of 241 Charnley total hip replacements performed between 1968 and 1974. In 1990, we reviewed 92 patients with 103 hips (96.3% of surviving hips) at a mean follow-up of 17.6 years (15 to 20.6) The clinical results were excellent, with Charnley scores of 4 or more for pain in 95% of the patients, for function in 73% and for movement in 93%. Of the whole series, 8.3% had been revised, and Kaplan-Meier survival analysis showed a probability of revision at 20 years of 10.7%. These results are similar to those from the few other series with extended follow-up, and make it difficult to justify the present widespread use of uncemented hip prostheses. It would seem that some aspects of the design of the first-generation Charnley stem were beneficial for long-term survival of the arthroplasty. We found no correlation between the clinical results and radiological loosening on the Harris scale

The effect of hypobaric spinal anaesthesia or narcotic-halothane-relaxant general anaesthesia on the incidence of postoperative deep vein thrombosis was studied in 140 elective total hip replacements in a prospective randomised manner. Deep vein thrombosis was diagnosed using impedance plethysmography and the 125I fibrinogen uptake test, combined, in selected cases, with ascending contrast venography. The overall incidence of deep vein thrombosis was 20%. Nine patients (13%) developed deep vein thrombosis in the spinal group and nineteen (27%) in the general anaesthetic group (p less than 0.05). The incidences of proximal thrombosis and of bilateral thrombi were also less with spinal anaesthesia than with general anaesthesia. It is concluded that spinal anaesthesia reduces the risks of postoperative thromboembolism in hip replacement surgery. The presence of varicose veins, being a non-smoker and having a low body mass index were associated with an increased incidence of deep vein thrombosis

Augmentation of the acetabular component of total hip replacements is a method of increasing stability and preventing recurrent dislocation. We report a series of mechanical experiments designed to evaluate the turning moments and angles required to dislocate standard, long posterior wall and two different augmented prostheses

We report the short-term follow-up, functional outcome and incidence of early and late infection after total hip replacement (THR) in a group of HIV-positive patients who do not suffer from haemophilia or have a history of intravenous drug use. A total of 29 patients underwent 43 THRs, with a mean follow-up of three years and six months (five months to eight years and two months). There were ten women and 19 men, with a mean age of 47 years and seven months (21 years to 59 years and five months). No early (< 6 weeks) or late (> 6 weeks) complications occurred following their THR. The mean pre-operative Harris hip score (HHS) was 27 (6 to 56) and the mean post-operative HHS was 86 (73 to 91), giving a mean improvement of 59 points (p = < 0.05, Student’s t-test). No revision procedures had been undertaken in any of the patients, and none had any symptoms consistent with aseptic loosening. This study demonstrates that it is safe to perform THR in HIV-positive patients, with good short-term functional outcomes and no apparent increase in the risk of early infection.

Cite this article: Bone Joint J 2014; 96-B:462–6.

We reviewed the results of 545 consecutive total hip replacements using a cementless non-coated high-density polyethylene acetabular component combined with a cemented Muller stem at five to 10 years. In all, 421 patients (445 hips) were available for review, 118 by questionnaire and 303 by examination and radiography. Of these, 86% had a good or excellent result. We found a high rate of radiological loosening of the cup after the sixth year, and a high rate of clinical loosening after the eighth year. Loosening was commoner in women, in younger patients and where a smaller size of acetabulum had been used. Calcar resorption was significantly related to loosening of the acetabulum. Loosening appeared to be mainly due to polyethylene debris produced by micro-movement of the acetabulum against the bone, which had resulted in a giant cell foreign body reaction and subsequent bone erosion. We have abandoned the use of this prosthesis and suggest that direct contact between bone and polyethylene should be prevented by a coating of metal or some other material

There is no diagnostic, non-invasive method for the early detection of loosening after total hip arthroplasty. In a pilot study, we have analysed two serum markers of bone remodelling, procollagen I C-terminal extension peptide (PICP) and cross-linked N-terminal telopeptide (NTx), as well as the diagnostic performance of NTx for the assessment of osteolysis. We recruited 21 patients with loosening (group I), 18 with a well-fixed prosthesis (group II) and 17 at the time of primary arthroplasty for osteoarthritis (OA) (group III). Internal normal reference ranges were obtained from 30 healthy subjects (group IV). The serum PICP level was found to be significantly lower in patients with OA and those with loosening, when compared with those with stable implants, while the NTx level was significantly increased only in the group with loosening, suggesting that collagen degradation depended on the altered bone turnover induced by the implant. This hypothesis was reinforced by the finding that the values in the pre-surgery patients and stable subjects were comparable with the reference range of younger healthy subjects. A high specificity and positive predictive value for NTx provided good diagnostic evidence of agreement between the test and the clinical and radiological evaluations. The NTx level could be used to indicate stability of the implant. However, further prospective, larger studies are necessary

It has been suggested that the wear of ultra-high molecular weight polyethylene (UHMWPE) in total hip replacement is substantially reduced when the femoral head is ceramic rather than metal. However, studies of alumina and zirconia ceramic femoral heads on the penetration of an UHMWPE liner in vivo have given conflicting results. The purpose of this study was to examine the surface characteristics of 30 alumina and 24 zirconia ceramic femoral heads and to identify any phase transformation in the zirconia heads. We also studied the penetration rate of alumina and zirconia heads into contemporary UHMWPE liners. The alumina heads had been implanted for a mean of 11.3 years (8.1 to 16.2) and zirconia heads for a mean of 9.8 years (7.5 to 15). The mean surface roughness values of the explanted alumina heads (Ra 40.12 nm and Rpm 578.34 nm) were similar to those for the explanted zirconia heads (Ra 36.21 nm and Rpm 607.34 nm). The mean value of the monoclinic phase of two control zirconia heads was 1% (0.8% to 1.5%) and 1.2% (0.9% to 1.3%), respectively. The mean value of the monoclinic phase of 24 explanted zirconia heads was 7.3% (1% to 26%). In the alumina group, the mean linear penetration rate of the UMWPE liner was 0.10 mm/yr (0.09 to 0.12) in hips with low Ra and Rpm values (13.22 nm and 85.91 nm, respectively). The mean linear penetration rate of the UHMWPE liner was 0.13 mm/yr (0.07 to 0.23) in hips with high Ra and Rpm values (198.72 nm and 1329 nm, respectively). This difference was significant (p = 0.041). In the zirconia head group, the mean linear penetration rate of the UHMWPE liner was 0.09 mm/yr (0.07 to 0.14) in hips with low Ra and Rpm values (12.78 nm and 92.99 nm, respectively). The mean linear penetration rate of the UHMWPE liner was 0.12 mm/yr (0.08 to 0.22) in hips with high Ra and Rpm values (199.21 nm and 1381 nm, respectively). This difference was significant (p = 0.039). The explanted zirconia heads which had a minimal phase transformation had similar surface roughness and a similar penetration rate of UHMWPE liner as the explanted alumina head

Dislocation is one of the most common causes of patient and surgeon dissatisfaction following hip replacement and to treat it, the causes must first be understood. Patient factors include age greater than 70 years, medical comorbidities, female gender, ligamentous laxity, revision surgery, issues with the abductors, and patient education. Surgeon factors include the annual quantity of procedures and experience, the surgical approach, adequate restoration of femoral offset and leg length, component position, and soft-tissue or bony impingement. Implant factors include the design of the head and neck region, and so-called skirts on longer neck lengths. There should be offset choices available in order to restore soft-tissue tension. Lipped liners aid in gaining stability, yet if improperly placed may result in impingement and dislocation. Late dislocation may result from polyethylene wear, soft-tissue destruction, trochanteric or abductor disruption and weakness, or infection. Understanding the causes of hip dislocation facilitates prevention in a majority of instances. Proper pre-operative planning includes the identification of patients with a high offset in whom inadequate restoration of offset will reduce soft-tissue tension and abductor efficiency. Component position must be accurate to achieve stability without impingement. Finally, patient education cannot be over-emphasised, as most dislocations occur early, and are preventable with proper instructions.

Cite this article: Bone Joint J 2013;95-B, Supple A:67–9.

The effects of surgical approach in total hip replacement on health-related quality of life and long-term pain and satisfaction are unknown. From the Swedish Hip Arthroplasty Register, we extracted data on all patients that had received a total hip replacement for osteoarthritis through either the posterior or the direct lateral approach, with complete pre- and one-year post-operative Patient Reported Outcome Measures (PROMs). A total of 42 233 patients met the inclusion criteria and of these 4962 also had complete six-year PROM data. The posterior approach resulted in an increased mean satisfaction score of 15 (sd 19) vs 18 (sd 22) (p <  0.001) compared with the direct lateral approach. The mean pain score was 13 (sd 17) vs 15 (sd 19) (p < 0.001) and the proportion of patients with no or minimal pain was 78% vs 74% (p < 0.001) favouring the posterior approach. The patients in the posterior approach group reported a superior mean EQ-5D index of 0.79 (sd 0.23) vs 0.77 (sd 0.24) (p < 0.001) and mean EQ score of 76 (sd 20) vs 75 (sd 20) (p < 0.001). All observed differences between the groups persisted after six years follow-up. Although PROMs after THR in general are very good regardless of surgical approach, the results indicate that some patients operated by the direct lateral approach report an inferior outcome compared with the posterior approach. The large number of procedures and the seemingly sustained differences make it likely these findings are clinically relevant.

Cite this article: Bone Joint J 2014;96-B:590–6.

Aims

Loss or absence of proximal femoral bone in revision total hip arthroplasty (THA) remains a significant challenge. While the main indication for the use of proximal femoral replacements (PFRs) is in the treatment of malignant disease, they have a valuable role in revision THA for loosening, fracture and infection in patients with bone loss. Our aim was to determine the clinical outcomes, implant survivorship, and complications of PFRs used in revision THA for indications other than malignancy.

Aims

The aim of this study was to compare early functional and health related quality of life outcomes (HRQoL) in patients who have undergone total hip arthroplasty (THA) using a bone conserving short stem femoral component and those in whom a conventional length uncemented component was used. Outcome was assessed using a validated performance based outcome instrument as well as patient reported outcome measures (PROMs).

Hip replacement is a very successful operation and the outcome is usually excellent. There are recognised complications that seem increasingly to give rise to litigation. This paper briefly examines some common scenarios where litigation may be pursued against hip surgeons. With appropriate record keeping, consenting and surgical care, the claim can be successfully defended if not avoided. We hope this short summary will help to highlight some common pitfalls. There is extensive literature available for detailed study.

We studied 1162 consecutive total hip replacements (THR) to establish the incidence of fatal pulmonary embolism (PE), clinical non-fatal PE and deep-vein thrombosis (DVT) in the six months after surgery. Chemical thromboprophylaxis had not been routinely used. We used a validated questionnaire supplemented by post-mortem records and a review of the clinical notes. Follow-up was 100%. The death rate from PE was 0.34% (95% CI 0.09 to 0.88), with one fatal PE after discharge 40 days after operation. The clinical PE rate confirmed by imaging was 1.20% (CI 0.65 to 2.02), with 0.7% of patients readmitted. The venographically-confirmed clinical DVT rate was 1.89% (CI 1.11 to 2.76), with 1.13% readmitted. The total thromboembolic morbidity was 3.4% (95% CI 2.5% to 4.7%); prophylaxis to reduce this would be justifiable if the complications of such prophylaxis did not produce an alternative morbidity. The fatal PE rate after THR without routine chemical prophylaxis was low; a very large randomised clinical trial would be required to demonstrate directly whether any prophylactic measure could reduce this. There is a large discrepancy between the high DVT rate reported in clinical trials using universal screening venography and the symptomatic DVT rate shown in this study. We found insufficient evidence to recommend continuing thromboprophylaxis after discharge from hospital

We made a study of 49 total hip arthroplasties at five years, comparing the Charnley hip score, the Nottingham Health Profile (NHP) score and the appearance on serial radiographs. Each of the three investigations was performed by an independent observer with no knowledge of the results of the other two studies. The eight patients with radiographic signs of prosthetic loosening had significant reductions in function and quality of life as measured by the NHP questionnaire, but no differences in the mean Charnley hip scores. None of the eight patients had clinical signs of prosthetic loosening sufficient to recommend revision of their THR. The NHP is a relatively low-cost method of providing long-term follow-up of THR

The peri-prosthetic tissue response to wear debris is complex and influenced by various factors including the size, area and number of particles. We hypothesised that the ‘biologically active area’ of all metal wear particles may predict the type of peri-prosthetic tissue response.

Peri-prosthetic tissue was sampled from 21 patients undergoing revision of a small diameter metal-on-metal (MoM) total hip arthroplasty (THA) for aseptic loosening. An enzymatic protocol was used for tissue digestion and scanning electron microscope was used to characterise particles. Equivalent circle diameters and particle areas were calculated. Histomorphometric analyses were performed on all tissue specimens. Aspirates of synovial fluid were collected for analysis of the cytokine profile analysis, and compared with a control group of patients undergoing primary THA (n = 11) and revision of a failed ceramic-on-polyethylene arthroplasty (n = 6).

The overall distribution of the size and area of the particles in both lymphocyte and non-lymphocyte-dominated responses were similar; however, the subgroup with lymphocyte-dominated peri-prosthetic tissue responses had a significantly larger total number of particles.

14 cytokines (interleukin (IL)-1ß, IL-2, IL-4, IL-5, IL-6, IL-10, IL-13, IL-17, interferon (IFN)-γ, and IFN-gamma-inducible protein 10), chemokines (macrophage inflammatory protein (MIP)-1α and MIP-1ß), and growth factors (granulocyte macrophage colony stimulating factor (GM-CSF) and platelet derived growth factor) were detected at significantly higher levels in patients with metal wear debris compared with the control group.

Significantly higher levels for IL-1ß, IL-5, IL-10 and GM-CSF were found in the subgroup of tissues from failed MoM THAs with a lymphocyte-dominated peri-prosthetic response compared with those without this response.

These results suggest that the ‘biologically active area’ predicts the type of peri-prosthetic tissue response. The cytokines IL-1ß, IL-5, IL-10, and GM-CSF are associated with lymphocyte-dominated tissue responses from failed small-diameter MoM THA.

Cite this article: Bone Joint J 2015;97-B:917–23.