The orientation of the acetabular component can influence both the short- and long-term outcomes of total hip replacement (THR). We performed a prospective, randomised, controlled trial of two groups, comprising of 40 patients each, in order to compare freehand introduction of the component with introduction using the transverse acetabular ligament (TAL) as a reference for anteversion. Anteversion and inclination were measured on pelvic radiographs. With respect to anteversion, in the freehand group 22.5% of the components were outside the safe zone versus 0% in the transverse acetabular ligament group (p = 0.002). The mean angle of anteversion in the freehand group was 21° (2° to 35°) which was significantly higher compared with 17° (2° to 25°) in the TAL group (p = 0.004). There was a significant difference comparing the variations of both groups (p = 0.008). With respect to inclination, in the freehand group 37.5% of the components were outside the safe zone versus 20% in the TAL group (p = 0.14). There was no significant difference regarding the accuracy or variation of the angle of inclination when comparing the two groups. . The transverse acetabular ligament may be used to obtain the appropriate anteversion when introducing the acetabular component during THR, but not acetabular component inclination. . Cite this article: Bone Joint J 2014;96-B:312–18

We treated 98 patients with peri-acetabular tumours by resection and reconstruction with a custom-made pelvic endoprosthesis. The overall survival of the patients was 67% at five years, 54% at ten years and 51% at 30 years. One or more complications occurred in 58.1% of patients (54), of which infection was the most common, affecting 30% (28 patients). The rate of local recurrence was 31% (29 patients) after a mean follow-up of 71 months (11 to 147). Dislocation occurred in 20% of patients (19). Before 1996 the rate was 40.5% (17 patients) but this was reduced to 3.9% (two patients) with the introduction of a larger femoral head. There were six cases of palsy of the femoral nerve with recovery in only two. Revision or excision arthroplasty was performed in 23.7% of patients (22), principally for uncontrolled infection or aseptic loosening. Higher rates of death, infection and revision occurred in men. This method of treatment is still associated with high morbidity. Patients should be carefully selected and informed of this pre-operatively

Evaluating musculoskeletal conditions of the lower limb and understanding the pathophysiology of complex bone kinematics is challenging. Static images do not take into account the dynamic component of relative bone motion and muscle activation. Fluoroscopy and dynamic MRI have important limitations. Dynamic CT (4D-CT) is an emerging alternative that combines high spatial and temporal resolution, with an increased availability in clinical practice. 4D-CT allows simultaneous visualization of bone morphology and joint kinematics. This unique combination makes it an ideal tool to evaluate functional disorders of the musculoskeletal system. In the lower limb, 4D-CT has been used to diagnose femoroacetabular impingement, patellofemoral, ankle and subtalar joint instability, or reduced range of motion. 4D-CT has also been used to demonstrate the effect of surgery, mainly on patellar instability. 4D-CT will need further research and validation before it can be widely used in clinical practice. We believe, however, it is here to stay, and will become a reference in the diagnosis of lower limb conditions and the evaluation of treatment options.

Cite this article: Bone Joint J 2021;103-B(5):822–827.

The identification of high-risk factors in patients with fractures of the pelvis at the time of presentation would facilitate investigation and management. In a series of 174 consecutive patients with unstable fractures of the pelvic ring, clinical data were used to calculate the injury severity score (ISS), the triage-revised trauma score (T-RTS), and the Glasgow coma scale (GCS). The morphology of the fracture was classified according to the AO system and that of Burgess et al. The data were analysed using univariate and multivariate methods in order to determine which presenting features were identified with high risk. Univariate analysis showed an association between mortality and an ISS over 25, a T-RTS below eight, age over 65 years, systolic blood pressure under 100 mmHg, a GCS of less than 8, blood transfusion of more than ten units in the first 24 hours and colloid infusion of more than six litres in the first 24 hours. Multivariate analysis showed that age, T-RTS and ISS were independent determinants of mortality. A T-RTS of eight or less identified the cohort of patients at greatest risk (65%). The morphology of the fracture was not predictive of mortality. We recommend the use of the T-RTS in the acute situation in order to identify patients at high risk

Aims

Chondrosarcoma is the second most common primary sarcoma of bone: conventional chondrosarcoma accounts for 85% of all cases. Conventional chondrosarcoma may be central or peripheral. Most studies group central and peripheral chondrosarcomas together, although there is growing evidence that their clinical behaviour and prognosis differ. The aims of this study were to analyze any differences in characteristics between central and peripheral chondrosarcomas and to investigate the incidence and role of different syndromes.

Aims

Open reduction in developmental dysplasia of the hip (DDH) is regularly performed despite screening programmes, due to failure of treatment or late presentation. A protocol for open reduction of DDH has been refined through collaboration between surgical, anaesthetic, and nursing teams to allow same day discharge. The objective of this study was to determine the safety and feasibility of performing open reduction of DDH as a day case.

Femoroacetabular impingement is a cause of hip pain in adults and is potentially a precursor of osteoarthritis. Our aim in this study was to determine the prevalence of bilateral deformity in patients with symptomatic cam-type femoroacetabular impingement as well as the presence of associated acetabular abnormalities and hip pain. We included all patients aged 55 years or less seen by the senior author for hip pain, with at least one anteroposterior and lateral pelvic radiograph available. All patients with dysplasia and/or arthritis were excluded. A total of 113 patients with a symptomatic cam-impingement deformity of at least one hip was evaluated. There were 82 men and 31 women with a mean age of 37.9 years (16 to 55). Bilateral cam-type deformity was present in 88 patients (77.8%) while only 23 of those (26.1%) had bilateral hip pain. Painful hips had a statistically significant higher mean alpha angle than asymptomatic hips (69.9° vs 63.1°, p < 0.001). Hips with an alpha angle of more than 60° had an odds ratio of being painful of 2.59 (95% confidence interval 1.32 to 5.08, p = 0.006) compared with those with an alpha angle of less than 60°. Of the 201 hips with a cam-impingement deformity 42% (84) also had a pincer deformity. Most patients with cam-type femoroacetabular impingement had bilateral deformities and there was an associated acetabular deformity in 84 of 201 patients (42%). This information is important in order to define the natural history of these deformities, and to determine treatment

We performed a retrospective examination of the anteroposterior pelvic CT scout views of 419 randomly selected patients between April 2004 and August 2009 in order to determine the prevalence of cam-type femoroacetabular deformity in the asymptomatic population. The CT scans had all been undertaken for conditions unrelated to disorders of the hip. The frequency of cam-type femoroacetabular deformity was assessed by measuring the α-angle of each hip on the anteroposterior images. The α-angles were classified according to the Copenhagen Osteoarthritis Study. Among 215 male hips (108 patients) the mean α-angle was 59.12° (37.75° to 103.50°). Of these, a total of 30 hips (13.95%) were defined as pathological, 32 (14.88%) as borderline and 153 (71.16%) as normal. Among 540 female hips (272 patients) the mean α-angle was 45.47° (34.75° to 87.00°), with 30 hips (5.56%) defined as pathological, 33 (6.11%) as borderline and 477 (88.33%) as normal. It appears that the cam-type femoroacetabular deformity is not rare among the asymptomatic population. These anatomical abnormalities, as determined by an increased α-angle, appear to be twice as frequent in men as in women. Although an association between osteoarthritis and femoroacetabular impingement is believed to exist, a long-term epidemiological study is needed to determine the natural history of these anatomical abnormalities

Aims

Despite the COVID-19 pandemic, incidence of hip fracture has not changed. Evidence has shown increased mortality rates associated with COVID-19 infection. However, little is known about the outcomes of COVID-19 negative patients in a pandemic environment. In addition, the impact of vitamin D levels on mortality in COVID-19 hip fracture patients has yet to be determined.

We investigated the development of CT-based bony radiological parameters associated with femoroacetabular impingement (FAI) in a paediatric and adolescent population with no known orthopaedic hip complaints. We retrospectively reformatted and reoriented 225 abdominal CTs into standardised CT pelvic images with neutral pelvic tilt and inclination (244 female and 206 male hips) in patients ranging from two to 19 years of age (mean 10.4 years). The Tönnis angle, acetabular depth ratio, lateral centre–edge angle, acetabular version and α-angle were assessed. Acetabular measurements demonstrated increased acetabular coverage with age and/or progressive ossification of the acetabulum. The α-angle decreased with age and/or progressive cortical bone development and resultant narrowing of the femoral neck. Cam and pincer morphology occurred as early as ten and 12 years of age, respectively, and their prevalence in the adolescent patient population is similar to that reported in the adult literature. Future aetiological studies of FAI will need to focus on the early adolescent population. Cite this article: Bone Joint J 2013;95-B:598–604

We have investigated the changes in the interposed capsule after a Chiari pelvic osteotomy, in an experimental study on dysplastic hips in 20 adolescent rabbits. Radiographic, macroscopic and microscopic observations were made up to 12 months after operation. The new acetabular roof had incorporated the interposed capsule and remodelled completely by six months. By 12 months there was a new, stable hip with continuity between the capsule and the original acetabular cartilage. Histologically, the capsule underwent metaplastic change to fibrocartilaginous tissue after six months, with some hyaline-like cartilage near the joint surface. These changes in the interposed capsule play an important role in the formation of a new joint after a Chiari pelvic osteotomy

We report a review of 33 hips (32 patients) which had required repeat open reduction for congenital dislocation of the hip. They were followed up for a mean of 76 months (36 to 132). Factors predisposing to failure of the initial open reduction were simultaneous femoral or pelvic osteotomy, inadequate inferior capsular release, and inadequate capsulorrhaphy. Avascular necrosis had developed in more than half the hips, usually before the final open reduction. At review, 11 of the hips (one-third) were in Severin grade 3 or worse; five had significant symptoms and only ten were asymptomatic and radiographically normal. Once redisplacement has occurred after primary open reduction, attempts to reduce the head by closed means or by pelvic or femoral osteotomy are usually unsuccessful and a further open reduction is necessary

Femoroacetabular cam impingement is thought to be a cause of premature osteoarthritis of the hip. The presence of cam malformation was determined in 2803 standardised anteroposterior (AP) pelvic radiographs from the Copenhagen Osteoarthritis Study by measuring the alpha (α) angle and the triangular index, a new measure of asphericity of the femoral head. In addition, the α-angle and the triangular index were assessed on the AP and lateral hip radiographs of 82 men and 82 women randomly selected from patients scheduled for total hip replacement (THR). The influence of varying femoral rotation on the α angle and the triangular index was also determined in femoral specimens under experimental conditions. From the 2803 radiographs the mean AP α-angle was 55° (30° to 100°) in men and 45° (34° to 108°) in women. Approximately 6% of men and 2% of women had cam malformation. The α-angle and triangular index were highly inter-related. Of those patients scheduled for THR, 36 men (44%) and 28 women (35%) had cam malformation identifiable on the AP radiographs. The triangular index proved to be more reliable in detecting cam malformation when the hip was held in varying degrees of rotation. The combination of the α-angle and the triangular index will allow examination of historical radiographs for epidemiological purposes in following the natural history of the cam deformity

We investigated the early results of modular porous metal components used in 23 acetabular reconstructions associated with major bone loss. The series included seven men and 15 women with a mean age of 67 years (38 to 81), who had undergone a mean of two previous revisions (1 to 7). Based on Paprosky’s classification, there were 17 type 3A and six type 3B defects. Pelvic discontinuity was noted in one case. Augments were used in 21 hips to support the shell and an acetabular component-cage construct was implanted in one case. At a mean follow-up of 41 months (24 to 62), 22 components remained well fixed. Two patients required rerevision of the liners for prosthetic joint instability. Clinically, the mean Harris Hip Score improved from 43.0 pre-operatively (14 to 86) to 75.7 post-operatively (53 to 100). The mean pre-operative Merle d’Aubigné score was 8.2 (3 to 15) and improved to a mean of 13.7 (11 to 18) post-operatively. These short-term results suggest that modular porous metal components are a viable option in the reconstruction of Paprosky type 3 acetabular defects. More data are needed to determine whether the system yields greater long-term success than more traditional methods, such as reconstruction cages and structural allografts

We treated four patients with periacetabular malignant tumours by pelvic reconstruction with a free vascularised fibular graft after resection of the tumour. The mean follow-up period was 32 months (9 to 39). The diagnosis was chondrosarcoma in three patients and osteosarcoma in one. In two patients total resection of the hemipelvis was required and in the other two less, but still massive, resection was undertaken. All were treated with an immediate free vascularised fibular graft which included arthrodesis of the hip and reconstruction of the pelvic ring. One patient died. The other three have remained free from recurrence. Solid union of the graft was achieved between four and 14 months after surgery. Shortening of the involved limbs was less than 2 cm. The patients had no pain and were independent walkers without external support. Emotional acceptance was satisfactory. Our results suggest that reconstruction with the use of a free vascularised graft is an alternative to other types of reconstructive procedure after resection of periacetabular tumours

Aims

Guided growth has been used to treat coxa valga for cerebral palsy (CP) children. However, there has been no study on the optimal position of screw application. In this paper we have investigated the influence of screw position on the outcomes of guided growth.

Stature and its components were examined in 143 girls aged 11 to 15 years with adolescent idiopathic scoliosis. Correction was made for loss of height due to the lateral spinal curvature, and the findings were compared with those from 202 healthy girls of similar age. Using three components of stature (suprapelvic, pelvic and subischial heights) we were able to show that the relatively greater stature of girls with adolescent idiopathic scoliosis was due to changes in the pelvis and lower limbs but not significantly in the spine. Suprapelvic height was reduced relative to subischial height; this probably represents the growth pattern of predominantly ectomorphic individuals, reflecting the physique of many of these girls. Pelvic height was disproportionately increased, and this is considered to be a true rather than an apparent difference. Cephalocaudal disproportion involving two segments suggests a common mechanism of causation which is unlikely to be secondary to the scoliosis. These physical features may in some way be associated with a predisposition to progression of the scoliosis

Aims

The primary aim of this study was to assess the independent association of the coronavirus disease 2019 (COVID-19) on postoperative mortality for patients undergoing orthopaedic and trauma surgery. The secondary aim was to identify factors that were associated with developing COVID-19 during the postoperative period.

1. Fifty dislocations and fracture-dislocations of the pelvis have been reviewed. 2. Complications were unusual. Two patients with rupture of the bladder died; two with rupture of the urethra survived. Of eight patients with retroperitoneal haemorrhage four died; the treatment advised is controlled blood transfusion maintaining a blood-pressure of not more than 100 mm. 3. Two types of pelvic disruption should be distinguished: 1) pubic injury with sacro-iliac dislocation; 2) pubic injury with fracture near the sacro-iliac joint. The first is twice as common as the second. 4. In each type, displacement is maintained by extension of the hip and outward roll of the limb. This may be controlled by the Watson-Jones plaster method but the pelvic sling technique is preferred and was used in all cases in this series. 5. The prognosis in fracture-dislocations is very good; nearly all patients went back to heavy work. 6. The prognosis in sacro-iliac dislocations is not so good; only half the patients went back to heavy work and there was often persistent sacro-iliac pain. Sacro-iliac arthrodesis is advised in those cases