Non-traumatic osteonecrosis of the femoral head
is a potentially devastating condition, the prevalence of which
is increasing. Many joint-preserving forms of treatment, both medical
and surgical, have been developed in an attempt to slow or reverse
its progression, as it usually affects young patients. However, it is important to evaluate the best evidence that is
available for the many forms of treatment considering the variation
in the demographics of the patients, the methodology and the outcomes
in the studies that have been published, so that it can be used
effectively. The purpose of this review, therefore, was to provide an up-to-date,
evidence-based guide to the management, both non-operative and operative,
of non-traumatic osteonecrosis of the femoral head. Cite this article:
We evaluated the potential of a vastus lateralis muscle flap in controlling infection after resection arthroplasty of the hip. We retrospectively reviewed 119 patients with 120 chronic infections after resection arthroplasty treated with this procedure. The flap was fixed with Mitek anchors in the acetabular cavity. The mean duration of infection after resection before the muscle flap procedure was 6.5 months (2 to 13). The patients had previously undergone a mean of 4.9 operations (2 to 25). In all patients the infected cavity was the origin of the persistent infection. The mean follow-up was for 2.6 years (1.0 to 4.7). No patient had recurrent infection post-operatively and all had an improvement in the pain and better quality of life.
A 30-year-old man presented with pain and limitation of movement of the right hip. The symptoms had failed to respond to conservative treatment. Radiographs and CT scans revealed evidence of impingement between the femoral head-neck junction and an abnormally large anterior inferior iliac spine. Resection of the hypertrophic anterior inferior iliac spine was performed which produced full painless restoration of function of the hip. Hypertrophy of the anterior inferior iliac spine as a cause of femoro-acetabular impingement has not previously been described.
The December 2015 Hip &
Pelvis Roundup360 looks at: Vitamin E infusion helpful in polyethylene; Hip replacement in fracture and arthritis; Non-surgical treatment for arthritis; Cost and approach in hip surgery; Who does well in FAI surgery?; AAOS Thromboembolism guidelines; Thromboprophylaxis and periprosthetic joint infection; Fluid collections not limited to metal-on-metal THR
Excision of the proximal femur for tumour with
prosthetic reconstruction using a bipolar femoral head places a considerable
load on the unreplaced acetabulum. We retrospectively reviewed the changes which occur around the
affected hip joint by evaluating the post-operative radiographs
of 65 consecutive patients who underwent proximal prosthetic arthroplasty
of the femur, and in whom an acetabular component had not been used.
There were 37 men and 28 women with a mean age of 57.3 years (17
to 93). Radiological assessment included the extent of degenerative
change in the acetabulum, heterotopic ossification, and protrusio
acetabuli. The mean follow-up was 9.1 years (2 to 11.8). Degenerative changes
in the acetabulum were seen in three patients (4.6%), Brooker grade
1 or 2 heterotopic ossification in 17 (26%) and protrusion of the
prosthetic head in nine (13.8%). A total of eight patients (12.3%) needed a revision. Five were
revised to the same type of prosthesis and three (4.6%) were converted
to a total hip arthroplasty. We conclude that radiological evidence of degenerative change,
heterotopic ossification and protrusion occur in a few patients
who undergo prosthetic arthroplasty of the proximal femur for tumour.
The limited extent of these changes and the lack of associated symptoms
do not justify the routine arthroplasty of the acetabulum in these patients. Cite this article:
We describe our technique and rationale using
hybrid fixation for primary total hip arthroplasty (THA) at the Hospital
for Special Surgery. Modern uncemented acetabular components have
few screw holes, or no holes, polished inner surfaces, improved
locking mechanisms, and maximised thickness and shell-liner conformity. Uncemented
sockets can be combined with highly cross-linked polyethylene liners,
which have demonstrated very low wear and osteolysis rates after
ten to 15 years of implantation. The results of cement fixation
with a smooth or polished surface finished stem have been excellent,
virtually eliminating complications seen with cementless fixation
like peri-operative femoral fractures and thigh pain. Although mid-term
results of modern cementless stems are encouraging, the long-term
data do not show reduced revision rates for cementless stems compared
with cemented smooth stems. In this paper we review the conduct
of a hybrid THA, with emphasis on pre-operative planning, surgical
technique, hypotensive epidural anaesthesia, and intra-operative
physiology. Cite this article:
We have developed an animal model to examine the formation of heterotopic ossification using standardised muscular damage and implantation of a beta-tricalcium phosphate block into a hip capsulotomy wound in Wistar rats. The aim was to investigate how cells originating from drilled femoral canals and damaged muscles influence the formation of heterotopic bone. The femoral canal was either drilled or left untouched and a tricalcium phosphate block, immersed either in saline or a rhBMP-2 solution, was implanted. These implants were removed at three and 21 days after the operation and examined histologically, histomorphometrically and immunohistochemically. Bone formation was seen in all implants in rhBMP-2-immersed, whereas in those immersed in saline the process was minimal, irrespective of drilling of the femoral canals. Bone mineralisation was somewhat greater in the absence of drilling with a mean mineralised volume to mean total volume of 18.2% ( Our findings suggest that osteoinductive signalling is an early event in the formation of ectopic bone. If applicable to man the results indicate that careful tissue handling is more important than the prevention of the dissemination of bone cells in order to avoid heterotopic ossification.
Polyethylene liners of modular acetabular components wear sometimes need to be replaced, despite the metal shell being well fixed. Replacing the liner is a relatively simple procedure, but very little is known of the outcome of revision. We prospectively followed up 1126 Harris-Galante I metal-backed, uncemented components for between nine and 19 years. We found 38 (3.4%) liners of 1126 acetabular components wore and required revision. These revisions were then followed up for a mean of 4.8 years. The rate of dislocation was 28.9%. Nine of the dislocations occurred once and two were recurrent. The overall secondary revision rate was three of 38 total hip replacements (7.9%) at a mean follow-up of 4.8 years. This gives a 92.1% survivorship (35 of 38) at under five years. In isolated revision of a liner, we had a complication rate of 23% (three of 13). In revision of a liner combined with revision of the femoral stem, there was a complication rate of 48% (12 of 25). We discuss possible reasons for the high dislocation rates. Leaving the well-fixed acetabular shell
Our objective was to predict the knee extension strength and post-operative function in quadriceps resection for soft-tissue sarcoma of the thigh. A total of 18 patients (14 men, four women) underwent total or partial quadriceps resection for soft-tissue sarcoma of the thigh between 2002 and 2014. The number of resected quadriceps was surveyed, knee extension strength was measured with the Biodex isokinetic dynamometer system (affected side/unaffected side) and relationships between these were examined. The Musculoskeletal Tumor Society (MSTS) score, Toronto Extremity Salvage Score (TESS), European Quality of Life-5 Dimensions (EQ-5D) score and the Short Form 8 were used to evaluate post-operative function and examine correlations with extension strength. The cutoff value for extension strength to expect good post-operative function was also calculated using a receiver operating characteristic (ROC) curve and Fisher’s exact test.Objectives
Methods
In order to determine the potential for an internervous safe zone, 20 hips from human cadavers were dissected to map out the precise pattern of innervation of the hip capsule. The results were illustrated in the form of a clock face. The reference point for measurement was the inferior acetabular notch, representing six o’clock. Capsular branches from between five and seven nerves contributed to each hip joint, and were found to innervate the capsule in a relatively constant pattern. An internervous safe zone was identified anterosuperiorly in an arc of 45° between the positions of one o’clock and half past two. Our study shows that there is an internervous zone that could be safely used in a capsule-retaining anterior, anterolateral or lateral approach to the hip, or during portal placement in hip arthroscopy.
We evaluated an operative technique, described
by the Exeter Hip Unit, to assist accurate introduction of the femoral
component. We assessed whether it led to a reduction in the rate
of leg-length discrepancy after total hip arthroplasty (THA). A total of 100 patients undergoing THA were studied retrospectively;
50 were undertaken using the test method and 50 using conventional
methods as a control group. The groups were matched with respect
to patient demographics and the grade of surgeon. Three observers
measured the depth of placement of the femoral component on post-operative
radiographs and measured the length of the legs. There was a strong correlation between the depth of insertion
of the femoral component and the templated depth in the test group
(R = 0.92), suggesting accuracy of the technique. The mean leg-length
discrepancy was 5.1 mm (0.6 to 21.4) pre-operatively and 1.3 mm
(0.2 to 9.3) post-operatively. There was no difference between Consultants
and Registrars as primary surgeons. Agreement between the templated
and post-operative depth of insertion was associated with reduced
post-operative leg-length discrepancy. The intra-class coefficient
was R ≥ 0.88 for all measurements, indicating high observer agreement.
The post-operative leg-length discrepancy was significantly lower
in the test group (1.3 mm) compared with the control group (6.3
mm, p <
0.001). The Exeter technique is reproducible and leads to a lower incidence
of leg-length discrepancy after THA. Cite this article:
Femoral stem version has a major influence on
impingement and early post-operative stability after total hip arthroplasty
(THA). The main objective of this study was to evaluate the validity
of a novel radiological method for measuring stem version. Anteroposterior
(AP) radiographs and three-dimensional CT scans were obtained for
115 patients (female/male 63/72, mean age 62.5 years (50 to 75))
who had undergone minimally invasive, cementless THA. Stem version was
calculated from the AP hip radiograph by rotation-based change in
the projected prosthetic neck–shaft (NSA*) angle using the mathematical
formula ST = arcos [tan (NSA*) / tan (135)]. We used two independent
observers who repeated the analysis after a six-week interval. Radiological
measurements were compared with 3D-CT measurements by an independent,
blinded external institute. We found a mean difference of 1.2° ( We found that femoral tilt was associated with the mean radiological
measurement error (r = 0.22, p = 0.02). The projected neck–shaft angle is a reliable method for measuring
stem version on AP radiographs of the hip after a THA. However,
a highly standardised radiological technique is required for its
precise measurement. Cite this article:
The aim of this study was to evaluate the functional
and oncological outcome of extracorporeally irradiated autografts
used to reconstruct the pelvis after a P1/2 internal hemipelvectomy. The study included 18 patients with a primary malignant bone
tumour of the pelvis. There were 13 males and five females with
a mean age of 24.8 years (8 to 62). Of these, seven had an osteogenic
sarcoma, six a Ewing’s sarcoma, and five a chondrosarcoma. At a
mean follow-up of 51.6 months (4 to 185), nine patients had died
with metastatic disease while nine were free from disease. Local
recurrence occurred in three patients all of whom eventually died of
their disease. Deep infection occurred in three patients and required
removal of their graft in two while the third underwent a hindquarter
amputation for extensive flap necrosis. The mean Musculoskeletal Tumor Society functional score of the
16 patients who could be followed-up for at least 12 months was
77% (50 to 90). Those 15 patients who completed the Toronto Extremity
Salvage Score questionnaire had a mean score of 71% (53 to 85). Extracorporeal irradiation and re-implantation of bone is a valid
method of reconstruction after an internal hemipelvectomy. It has
an acceptable morbidity and a functional outcome that compares favourably
with other available reconstructive techniques. Cite this article:
We report the kinematic and early clinical results
of a patient- and observer-blinded randomised controlled trial in which
CT scans were used to compare potential impingement-free range of
movement (ROM) and acetabular component cover between patients treated
with either the navigated ‘femur-first’ total hip arthroplasty (THA) method
(n = 66; male/female 29/37, mean age 62.5 years; 50 to 74) or conventional
THA (n = 69; male/female 35/34, mean age 62.9 years; 50 to 75).
The Hip Osteoarthritis Outcome Score, the Harris hip score, the
Euro-Qol-5D and the Mancuso THA patient expectations score were
assessed at six weeks, six months and one year after surgery. A
total of 48 of the patients (84%) in the navigated ‘femur-first’
group and 43 (65%) in the conventional group reached all the desirable
potential ROM boundaries without prosthetic impingement for activities
of daily living (ADL) in flexion, extension, abduction, adduction
and rotation (p = 0.016). Acetabular component cover and surface
contact with the host bone were >
87% in both groups. There was
a significant difference between the navigated and the conventional
groups’ Harris hip scores six weeks after surgery (p = 0.010). There
were no significant differences with respect to any clinical outcome
at six months and one year of follow-up. The navigated ‘femur-first’
technique improves the potential ROM for ADL without prosthetic
impingement, although there was no observed clinical difference
between the two treatment groups. Cite this article:
The use of robots in orthopaedic surgery is an
emerging field that is gaining momentum. It has the potential for significant
improvements in surgical planning, accuracy of component implantation
and patient safety. Advocates of robot-assisted systems describe
better patient outcomes through improved pre-operative planning
and enhanced execution of surgery. However, costs, limited availability,
a lack of evidence regarding the efficiency and safety of such systems
and an absence of long-term high-impact studies have restricted
the widespread implementation of these systems. We have reviewed
the literature on the efficacy, safety and current understanding of
the use of robotics in orthopaedics. Cite this article:
Pre-operative planning for total hip replacement
(THR) is challenging in hips with severe acetabular deformities, including
those with a hypoplastic acetabulum or severe defects and in the
presence of arthrodesis or ankylosis. We evaluated whether a Rapid
Prototype (RP) model, which is a life-sized reproduction based on
three-dimensional CT scans, can determine the feasibility of THR
and provide information about the size and position of the acetabular component
in severe acetabular deformities. THR was planned using an RP model
in 21 complex hips in five men (five hips) and 16 women (16 hips)
with a mean age of 47.7 years (24 to 70) at operation. An acetabular
component was implanted successfully and THR completed in all hips.
The acetabular component used was within 2 mm of the predicted size
in 17 hips (80.9%). All of the acetabular components and femoral
stems had radiological evidence of bone ingrowth and stability at
the final follow-up, without any detectable wear or peri-prosthetic
osteolysis. The RP model allowed a simulated procedure pre-operatively
and was helpful in determining the feasibility of THR pre-operatively,
and to decide on implant type, size and position in complex THRs. Cite this article:
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 ( Cite this article:
The piriformis muscle is an important landmark
in the surgical anatomy of the hip, particularly the posterior approach
for total hip replacement (THR). Standard orthopaedic teaching dictates
that the tendon must be cut in to allow adequate access to the superior
part of the acetabulum and the femoral medullary canal. However,
in our experience a routine THR can be performed through a posterior
approach without sacrificing this tendon. We dissected the proximal femora of 15 cadavers in order to clarify
the morphological anatomy of the piriformis tendon. We confirmed
that the tendon attaches on the crest of the greater trochanter,
in a position superior to the trochanteric fossa, away from the
entry point for broaching the intramedullary canal during THR. The
tendon attachment site encompassed the summit and medial aspect
of the greater trochanter as well as a variable attachment to the
fibrous capsule of the hip joint. In addition we dissected seven
cadavers resecting all posterior attachments except the piriformis
muscle and tendon in order to study their relations to the hip joint,
as the joint was flexed. At flexion of 90° the piriformis muscle
lay directly posterior to the hip joint. The piriform fossa is a term used by orthopaedic surgeons to
refer the trochanteric fossa and normally has no relation to the
attachment site of the piriformis tendon. In hip flexion the piriformis
lies directly behind the hip joint and might reasonably be considered
to contribute to the stability of the joint. We conclude that the anatomy of the piriformis muscle is often
inaccurately described in the current surgical literature and terms
are used and interchanged inappropriately. Cite this article:
Deficiency of the abductor mechanism is a well-recognised
cause of pain and limping after total hip replacement (THR). This
can be found incidentally at the time of surgery, or it may arise
as a result of damage to the superior gluteal nerve intra-operatively,
or after surgery owing to mechanical failure of the abductor muscle
repair or its detachment from the greater trochanter. The incidence
of abductor failure has been reported as high as 20% in some studies.
The management of this condition remains a dilemma for the treating
surgeon. We review the current state of knowledge concerning post-THR
abductor deficiency, including the aetiology, diagnosis and management,
and the outcomes of surgery for this condition. Cite this article: