Introduction

Short-stem hip arthroplasty is gaining popularity as a method of treating hip arthritis in biologically younger patients. The potential benefit of using a short-stem is preservation of bone in the proximal femur for a future revision. We have compared the early clinical and radiological results of a short-stem hip arthroplasty versus a conventional total hip arthroplasty (THA) using a standard length femoral prosthesis with particular focus on functional outcome.

Background

Hip replacement surgery is an effective treatment, however quantitative outcome does not necessarily delineate the true picture. It is important to triangulate data methods in order to ascertain important contextual factors that may influence patient perception.

Background

Hip arthroscopy is well established as a diagnostic and therapeutic tool in the native hip joint. However, its application in the symptomatic post-hip arthroplasty patient is still being explored.

Aim

The aim of this study was to assess the role of hip arthroscopy in the management of hip pain in elite athletes.

Acetabular chondral delamination is a frequent finding at hip arthroscopy. The cartilage is macroscopically normal but disrupted from the subchondral bone. Excision of chondral flaps is the usual procedure for this type of lesion. However, we report 19 consecutive patients in whom the delaminated chondral flap was re-attached to the underlying subchondral bone with fibrin adhesive. We used the modified Harris hip score for assessment of pain and function.

Improvement in pain and function was found to be statistically significant six months and one year after surgery. No local or general complications were noted. Three patients underwent further surgery for unrelated reasons. In each, the area of fibrin repair appeared intact and secure.

Our results suggest that fibrin is a safe agent to use for acetabular chondral delamination.

Isolated osteochondral defects (OCD) of the femoral head remain a challenging issue for the surgeons when trying to balance between a less invasive procedure and the maximum benefit for the patient. We present our experience of the Hemicap partial hip resurfacing system in 12 patients. In ten patiens the defects were identified arthroscopically. Seven of them had concurrent early degeneration of cartilage (OA, Grade I). Three patients had OCD surrounded by normal cartilage and two patients had avascular necrosis. The mean patient age was 41 years (30 to 63) and mean follow-up 27 months (range 9 to 48).

Five patients required a hip resurfacing arthroplasty or total hip replacement at a mean interval of 17 months (12 to 24) due to persistent pain. Three patients required further hip arthroscopy at a mean interval of 36 months (range, 24 to 48). Four patients did not require secondary surgery with mean follow-up 32.7 months (range, 9 to 43). In all hips with revision surgery the components were found to be stable and secure.

Partial resurfacing arthroplasty seems to have a tendency towards early failure, especially in OA patients, but more favourable results in AVN patients, and the surgeons should have a cautious approach to this type of arthroplasty.

Introduction: Femoroacetabular impingement (FAI) is an important cause of hip pain in young adults and a precursor to osteoarthritis. Morphological abnormality of either the acetabulum, proximal femur, or both, may result in FAI. The majority of patients however, have a cam deformity of the proximal femur. From a research perspective, FAI is an example of how subtle morphological abnormality results in a predictable pattern of cartilage damage, and thereby offers great potential as a model to study early degenerative disease and for clinical trials of joint preserving treatments. Accurate classification of the morphology of the hip is essential for this further study.

The aim of this study was to define normal, borderline, and abnormal parameters for the morphology of the proximal femur, in the context of the cam deformity, by studying asymptomatic individuals with normal clinical examination and no osteoarthritis from the general population.

Methods: 157 individuals (79 male, 78 female, mean age 46 years) with no previous history of hip problems were recruited. The participants were the spouses/partners of patients involved in a cohort study of osteoarthritis and FAI. All participants underwent clinical (interview, examination, and hip scores) and radiological assessment (standardised AP Pelvic and cross-table lateral radiographs of each hip). Radiographs were scored for the presence of osteoarthritis, and the morphology of the proximal femur was analysed. The alpha angle, anterior offset ratio, presence of a cam ‘bump’, synovial herniation pit were recorded in each hip.

Results: 21 subjects were excluded because they either had positive clinical features or radiological evidence of osteoarthritis (equivalent to a Kellgren and Lawrence grade of 2). From the remaining 136 subjects, with essentially ‘normal hips from the general population’, mean values for the alpha angle and anterior offset ratio were generated. Borderline and Abnormal values are suggested. Gender differences were noted with higher mean alpha angles and lower offset ratios occurring in men.

Discussion: Although it has limitations, standardised plain radiography remains the cheapest and most convenient way to screen an individual for the presence of a cam deformity. Despite the recent interest in FAI, our knowledge of what is normal in the general population, as assessed using appropriate radiographic techniques, is modest. The ranges provided by this study will facilitate the accurate classification of subjects with FAI, thereby providing guidance for surgeons treating such patients, and also enable the generation of refined cohorts for the study of the natural history of subtle morphological abnormalities of the hip, and for enrolment in clinical trials.

There is a known association between femoroacetabular impingement (FAI) and osteoarthritis of the hip. What is not known is whether arthroscopic excision of an impingement lesion can significantly improve a patient’s symptoms.

This study compares the one-year results of hip arthroscopy for cam-type FAI in two groups of patients. The study (osteoplasty) group comprised 24 patients (24 hips) with cam-type FAI who underwent arthroscopic debridement with excision of their impingement lesion. The control (no osteoplasty) group comprised 47 patients (47 hips) who underwent arthroscopic debridement without excision of their impingement lesion. In both groups, the presence of FAI was confirmed on pre-operative plain radiographs. The modified Harris hip score (MHHS) was used for evaluation pre-operatively and at one year’s follow-up. Non-parametric tests were used for statistical analysis.

A tendency towards higher median post-operative MHHS scores was observed in the study than in the control group (83 vs. 77, p = 0.11). This was supported by a significantly higher portion of patients in the osteoplasty group with excellent/good results (83% vs. 60%, p = 0.043). It appears that even further symptomatic improvement may be obtained after hip arthroscopy for FAI by means of the femoral osteoplasty. When treating cam impingement arthroscopically, both central and peripheral compartments of the hip should always be accessed.

Problems with chondral toxicity caused by prolonged exposure to local anaesthetics have been increasingly recognised. However, day-case hip arthroscopic surgery is frequently carried out using an intraarticular depot of local anaesthetic as post-operative analgesia plus additional opiate or oral analgesia as required. We aimed to evaluate the efficacy of three different post-operative analgesic regimes at hip arthroscopy, in particular examining whether intraarticular local anaesthetics gave any benefit.

We investigated 71 consecutive patients undergoing day-case hip arthroscopy and prospectively audited their post-operative analgesic requirements. Each patient was given one of three alternative post-operative analgesic regimes. Group A (n=29) received bupivicaine 0.25% 10ml intraarticular and 20ml peri-portal skin infiltration, group B (n=23) had bupivicaine 0.25% 20ml peri-portal skin infiltration only, and group C (n=19) had no infiltration. Outcome measures were visual analogue scores (VAS) at time-points T1 (immediate post-operatively), T2 (one hour post-operatively), T3 (two hours post-operatively), and T4 (four hours post-operatively). Total opiate consumption was also recorded.

There was significantly less post-operative pain in group A, compared with group C at T1 (p=0.03) and T2 (p=0.004), and compared with group B at T3 (p=0.02) and T4 (p=0.03). There were no significant differences in VAS between groups B and C at any time-points. Group A used significantly less opiates post-operatively compared with group B (p=0.008) or C (p< 0.001) but there was no significant difference in opiate use between groups B and C.

There are no previous studies relating to hip arthros-copy post-operative analgesic requirements. Intraarticular local anaesthetic significantly reduces post-operative pain, but at what cost to the chondral surface? Local skin infiltration of the arthroscopy portals does not significantly alter pain levels or opiate requirements. Avoidance of intararticular local anaesthetic raises opiate requirements. We require improved alternative analgesic regimes.

Introduction: Femoroacetabular impingement (FAI) is an important cause of hip pain in young adults and a precursor to osteoarthritis. Genetic factors are important in the aetiology of osteoarthritis of the hip. From a research perspective, FAI is an example of how subtle morphological abnormality results in a predictable pattern of cartilage damage, and thereby offers great potential as a model to study early degenerative disease.

Although many causes of FAI are described, the vast majority of patients give no history of previous hip disease. The purpose of this study was to investigate the extent to which FAI has an underlying genetic basis, by studying the siblings of patients undergoing surgery for FAI and comparing them with controls.

Methods: 66 patients (probands, 29 male, 37 female, mean age 39.1 years) treated surgically for FAI provided siblings for the study. These patients were classified as having cam, pincer or mixed FAI. 101 siblings (55 male, 56 female, mean age 38.2 years) were recruited. The control group consisted of the 77 partners of those siblings (40 male, 37 female, mean age 41.9 years). All subjects underwent clinical (interview, examination, and hip scores) and radiological assessment (standardised AP Pelvic and cross-table lateral radiographs of each hip). Radiographs were scored for the presence of osteoarthritis, and cam- and pincer-type abnormalities.

Results: Participants were classified as a) Normal morphology with no clinical features, b) Abnormal morphology but no clinical features c) Abnormal morphology with clinical signs but no symptoms, and d) Abnormal morphology with symptoms and signs. The sibling relative risks were significant for groups b, c, and d, supporting the hypothesis of an underlying genetic predisposition to FAI. Siblings usually demonstrated the same type of abnormal morphology as the proband. Gender specificity was apparent however, with pincer abnormalities which were usually apparent in female probands being common in sisters but less common in brothers. The brothers of probands with cam deformities almost universally demonstrated the same deformity, although only 50% of sisters did so.

Discussion: Genetic influences are important in the aetiology of FAI. Whether the morphological abnormality is determined at conception or by an inherited predisposition to an acquired event during maturity warrants further study. We have identified a spectrum of disease with a proportion of siblings with abnormal morphology currently asymptomatic. These cohorts present an opportunity to prospectively study the natural history of the condition, improve our understanding of the mechanisms and pathology in early degenerative disease, and potentially to be recruited into clinical trials of surgical and adjuvant treatments.

Introduction: Femoroacetabular impingement (FAI) causes pain in young adults and osteoarthritis. Genetic factors are important in the aetiology of osteoarthritis. We aimed to investigate the extent to which FAI has an underlying genetic basis, by studying the siblings of patients undergoing surgery for FAI and comparing them with controls.

Methods: 66 patients (probands, 29 male, 37 female, mean age 39.1 years) treated surgically for FAI provided siblings for the study. Probands were classified as having cam, pincer or mixed FAI. 101 siblings (55 male, 56 female, mean age 38.2 years) were recruited. The control group consisted of their 77 partners and was age and gender-matched. All subjects were assessed clinically and radiologically (standardised AP Pelvic and cross-table lateral radiographs of each hip). Radiographs were scored for the presence of osteoarthritis, and morphological abnormalities.

Participants were classified as:

Normal morphology, no clinical features

Results: The sibling relative risks were significant for groups b, c, and d (ranging between 2–5, p< 0.01). Pro-bands and siblings shared the same pattern of abnormal morphology. Gender specificity was apparent: pincer abnormalities common in sisters but not in brothers. The brothers of probands with cam deformities almost universally demonstrated the same deformity, but only 50% of sisters did.

Discussion: Genetic influences are important in the aetiology of FAI. Whether the morphological abnormality is determined at conception or by an inherited predisposition to an acquired event during development warrants further study. Symptoms are variable, indicating a spectrum of disease progression. These cohorts present an opportunity to prospectively study the natural history of the condition, improve understanding of the mechanisms and pathology, and potentially to be recruited into clinical trials.

Aim: The aim of this study was to assess the role of Hip Arthroscopy in the patient with a symptomatic Resurfacing arthroplasty of the hip.

Patients and Methods: Twelve consecutive patients who presented to our clinic with a painful resurfacing and indeterminate or normal investigations underwent an arthroscopy of their resurfacing were prospectively enrolled into the study following appropriate consent. The pre-operative investigations included haematological indices and acute phase reactants to rule out infection along with plain radiographs and an isotope bone scan.

Results: (table deleted)

Conclusions: Assessment of a symptomatic resurfacing is usually difficult and becomes more challenging in the background of normal or indeterminate investigations. However, in this situation, we found that in experienced hands, hip arthroscopy can be utilised as an effective tool for aiding diagnosis and offering therapeutic interventions in these patients.

Introduction and Aims: Although the association between femoroacetabular impingement and osteoarthritis is established, it is not yet clear which hips have the greatest likelihood to rapidly progress to end-stage disease. We investigated the possible relation of specific radiological parameters, each indicative of a structural aspect of the hip joint, to progression of osteoarthritis.

Materials and Methods: Pairs of plain anteroposterior pelvic radiographs, spaced at least 10 years apart, of 43 patients (47 hips) with pistol-grip deformity of the femur and mild (Tönnis grade 1) or moderate (Tönnis grade 2) arthritis were reviewed. Radiological measurements included the α-angle, the neck-shaft angle, the Tönnis angle, the centre-edge angle of Wiberg and the anatomical medial proximal femoral angle (MPFA). The presence of the cross-over sign and the posterior wall sign was also recorded. Grading of osteoarthritis was repeated on the final films. A logistic regression analysis model was constructed, to investigate the predictive ability of radiological parameters on progression of osteoarthritis.

Results: Of the 47 hips, 31 (66%) showed evidence of progression of arthritis. There was no difference in the prevalence of progression between hips with initial grade 1 and grade 2 arthritis (p = 0.32). Comparison of the hips that progressed and those that did not revealed a significant difference for the MPFA (82° vs. 85°, p = 0.006) and the presence of the posterior wall sign (39% vs. 6%, p = 0.04) only. The regression analysis model demonstrated a predictive ability of 32% for those two parameters, with an accuracy of 78.3%.

Discussion and Conclusion: Mild-to-moderate osteoarthritis in hips with a pistol-grip deformity will not progress rapidly in all patients. In one third of them, progression will take more than ten years to manifest. Other structural aspects, relating to the geometry of the proximal femur and the acetabulum, influence in part this phenomenon. A hip with cam impingement is not always destined to end-stage arthritic degeneration.

Introduction and Aims: There is a known association between femoroacetabular impingement (FAI) and osteoarthritis of the hip. What is not known is whether arthroscopic excision of an impingement lesion can significantly improve a patient’s symptoms.

Materials and Methods: This study compares the one-year results of hip arthroscopy for cam-type FAI in two groups of patients. The study (osteoplasty) group comprised 24 patients (24 hips) with cam-type FAI who underwent arthroscopic debridement with excision of their impingement lesion. The control (no osteoplasty) group comprised 47 patients (47 hips) who underwent arthroscopic debridement without excision of their impingement lesion. In both groups, the presence of FAI was confirmed on pre-operative plain radiographs. The modified Harris hip score (MHHS) was used for evaluation pre-operatively and at one year’s follow-up. Non-parametric tests were used for statistical analysis.

Results: A tendency towards higher median post-operative MHHS scores was observed in the study than in the control group (83 vs. 77, p = 0.11). This was supported by a significantly higher portion of patients in the osteoplasty group with excellent/good results (83% vs. 60%, p = 0.043).

Conclusions: It appears that even further symptomatic improvement may be obtained after hip arthroscopy for FAI by means of the femoral osteoplasty. When treating cam impingement arthroscopically, both central and peripheral compartments of the hip should always be accessed.

Introduction: There are a number of publications in the literature on managing post-operative pain and early rehabilitation after primary total hip replacement (THR). However, there has been very little work in the literature to study the influence of the anaesthetic technique used on the post-operative length of hospital stay following primary THR. We, therefore, wished to particularly study the influence of anaesthetic technique and the anaesthetist concerned on the length of hospital stay, as well as the effect of age and body mass index (BMI).

Methods: We studied 121 consecutive THRs in 109 patients. All procedures in our study were performed by the same surgeon using the same posterolateral approach, the same prosthetic design and the same physiotherapy protocol for all patients. Patients received either general anaesthesia alone (50 THRs) or a combination of general and local anaesthesia (lumbar plexus block; 71 THRs) from three separate anaesthetists. The mean age at the time of operation was 66.5 years (33 to 88). The influence of anaesthetist, anaesthetic technique, age of the patient and BMI on length of stay after primary THR was assessed separately.

Results: Our analysis showed that the length of hospital stay was greatly influenced by the anaesthetic technique used, those patients who received a lumbar plexus block having a shorter median length of hospital stay (3 days) than those who received general anaesthesia alone (5 days; p < 0.0001). The age of the patient was also critical (p = 0.003) as was the anaesthetist concerned (p = 0.01). BMI was unimportant.

Conclusions: For those surgeons who believe that a reduction in the length of hospital stay after primary THR is a worthwhile objective, we have one over-riding observation–the anaesthetic technique used is critical.

Introduction: A common criticism of the modern hip resurfacing arthroplasty is its high early complication rate, in particular femoral neck fracture, displacement of the acetabular component and avascular necrosis. The overall complication rate varies widely in different published series. The sometimes alarmingly high rate of complications, as much as 22% for femoral neck fractures alone (Mont et al. 2005), has deterred many surgeons from using resurfacing implants. As a specialist elective hip practice we wished to specifically determine the early complication rate of hip resurfacing arthroplasty using the metal-on-metal Cormet 2000 implants. We defined an early complication as any resurfacing procedure which required inpatient readmission and/or further intervention within 12 months of the primary operation.

Material and methods: We assessed 253 consecutive hip resurfacing procedures (226 patients). All procedures were performed by the same surgical team using the same surgical approach (posterolateral). Operations were performed between 2001–2005. The mean operating time for was 51.8 minutes. The mean age of patients was 50 years (27 to76) at the time of surgery. 141 patients (62.4%) were male and 85 (37.6%) were female. The preoperative diagnosis was osteoarthritis for the majority of patients 246 (97.2%), the remainder having avascular necrosis (4 cases, 1.6%), chondrolysis (2 cases, 0.8%) or large osteochondral defects (1 case, 0.4%).

Results: In this series there were two infections (one superficial and one deep), one intraoperative femoral neck fracture (converted to THR), no episodes of avascular necrosis, one revision because of acetabular component loosening and one readmission because of a postoperative haematoma 10 days after surgery. All together two patients needed a further operation within one year of the primary operation (one two-stage revision because of deep infection, one revision to THR because of acetabular component shift). The haematoma was treated conservatively. There was one deep vein thrombosis (DVT), one case of iliopsoas tendonitis, one case of trochanteric bursitis and one patient wore an abduction brace for 6 weeks because of slight instability although there was no dislocation. The patient with DVT was readmitted as an inpatient. The overall complication rate (readmission as an inpatient) was 1.6% (4 patients) with the Cormet 2000 implant. Reoperation rate was 1.2% (3 patients) (including the intraoperative conversion to THR).

Discussion: The Cormet 2000 is a fully uncemented hydroxy-apatite coated hip resurfacing implant. In our series we found a low early reoperation and infection rate. All the reoperations were performed for cases were the primary operation was carried out in the first 6 months of this series. There were no complications associated with the uncemented femoral component of the Cormet 2000 implant.

Introduction: Although there are a number of publications in the literature on managing post-operative pain and early rehabilitation after surgery in general, there has been little work on the influence of anaesthetic technique on the post-operative length of hospital stay following primary total hip replacement (THR). We wished to particularly study the influence of anaesthetic technique and the anaesthetist concerned on the length of hospital stay, as well as the effect of age and body mass index (BMI).

Methods: We studied 121 consecutive THRs in 109 patients. All procedures were performed by the same surgeon using the same posterolateral approach, prosthetic design and the same physiotherapy protocol. Patients received either general anaesthesia alone (50 THRs) or a combination of general and local anaesthesia (lumbar plexus block; 71 THRs) from three separate anaesthetists. The influence of anaesthetist, anaesthetic technique, age, and BMI on length of stay after primary THR was assessed separately.

Results: Our analysis showed that the length of hospital stay was greatly influenced by the anaesthetic technique used (p < 0.0001), those patients who received a lumbar plexus block having a shorter median length of hospital stay (3 days) than those who received general anaesthesia alone (5 days). The age of the patient was also critical (p = 0.003) as was the anaesthetist concerned (p = 0.01). BMI was unimportant.

Discussion: For those surgeons who believe that a reduction in the length of hospital stay after primary THR is a worthwhile objective, we have one over-riding observation – the anaesthetic technique used, and the anaesthetist involved, are critical.

Elevated serum cobalt and chromium ion levels associated with carcinogenesis and chromosomal damage in animals have raised concerns that metal-on-metal (MOM) total hip replacement (THR) in humans may produce the same effects over time. Considering that the risks may be related to the level of these ions in the body, this study compared the serum cobalt and chromium ion levels in patients with unilateral versus bilateral 28 mm diameter MOM THR.

All patients having THR at our institution were prospectively registered on a computerised database. From our database, we identified 108 patients with Ultima (Johnson and Johnson, Leeds) MOM THR with 28 mm bearing made of cobalt-chromium alloy. After patient review in clinic and before blood results were known, patient matching was performed by date after surgery at blood sampling, activity level and body mass. Using these stringent criteria, 11 unilateral THR could be adequately matched with 11 bilateral THR. Blood serum was taken with full anti-contamination protocols and serum analysed via inductively coupled plasma mass spectrometry.

The serum cobalt ion level after unilateral MOM THR was 4.4 times normal (median 22 nmol/L, range 15 to 37 nmol/L) compared to 8.4 times normal (median 42 nmol/L, range 19 to 221 nmol/L) for bilateral MOM THR (p=0.001). The serum chromium ion level after unilateral MOM THR was 3.8 times normal (median 19 nmol/L, range 2 to 35 nmol/L) compared to 10.4 times normal (median 52 nmol/L, range 19 to 287 nmol/ L) for bilateral MOM THR (p=0.04).

This study has shown that the serum cobalt and chromium ion levels in patients with bilateral MOM THR are significantly higher than those in patients with unilateral MOM THR. With levels of up to 50 times the upper limit of normal, this finding may be of relevance for the potential development of long-term side effects.

Metal-on-metal (MOM) bearings after total hip arthroplasty are known to elevate the serum concentrations of metal ions, raising concerns about the long-term effects. One potential modifier of ion release is the bearing diameter used. Resurfacing MOM bearings have a large surface area available for corrosion compared to the typical bearing size of 28 mm in total hip replacement (THR) but may benefit from improved lubrication and reduced production of corrodible wear debris. The net effect of these two variables on metal ion release is unknown. In this study, we compared the level of ion release in patients after large bearing MOM hip resurfacing arthroplasty with patient after small bearing MOM THR.

We measured the serum cobalt and chromium levels from 22 patients with large bearing diameter MOM hip resurfacing arthroplasty (Cormet 2000 and Birmingham Hip Resurfacing) and compared them to the serum cobalt and chromium levels of 22 patients with small bearing diameter (28 mm) MOM THR (Ultima). Patients were prospectively matched for activity level, body mass and date after surgery at blood sampling. All were at least 6 months after surgery.

We found the median cobalt and chromium levels after hip resurfacing arthroplasty to be 7.6 times normal (median 38 nmol/L, range 14 to 144 nmol/L) and 10.5 times normal (median 53 nmol/L, range 25 to 165 nmol/ L) respectively. This is compared to 4.4 times normal (median 22 nmol/L, range 15 to 87 nmol/L) for cobalt and 3.8 times normal (median 19 nmol/L, range 2 to 58 nmol/L) for chromium after 28 mm MOM THR (p=0.0021 and p< 0.0001).

Conclusion: Large diameter MOM bearings result in greater release of cobalt and chromium ions than do small diameter MOM bearings. This may be of relevance when the potential effects of long-term exposure to elevated these metal ions is considered.