Introduction

Hallux valgus surgical correction has a variable but significant risk of recurrence. Symptoms result from an iatrogenic first brachymetatarsia following the index surgical procedure. First metatarsal shortening has been shown to correlate with the onset of transfer metatarsalgia. We describe the use of the scarf osteotomy to both correct the recurrent deformity and lengthen the shortened first metatarsal.

Study Aim

To assess the impact of two oral thromboprophylaxis agents against Clexane with regard to range of movement (ROM) following TKR with or without haemostasis following tourniquet release.

Introduction

Osteochondral defects of the knee may occur following patella dislocation or following direct trauma or twisting injuries to the knee in adolescents. Often a diagnostic and therapeutic challenge, if these lesions are left, posttraumatic osteoarthritis may occur. This retrospective single centre study presents the short-term results following operative fixation of osteochondral fragments of the knee using Omnitech ® screws.

Introduction

This study investigates the effect of Rivaroxaban (Bayer HealthCare) on early post-operative stiffness in primary total knee replacement.

Purpose

This study investigates the effect of early tourniquet release on range of flexion following total knee replacement, and the influence of anticoagulation with Rivaroxaban and Clexane (Enoxaparin).

Objective: To assess the possible effect of intra-articular steroid injections to future TKA.

Materials-Method: We retrospectively studied all 231 patients who underwent AGC (Biomet) TKR in our hospital from February 2002 to October 2004. Twenty notes were not available in medical records and were excluded from the study. Other exclusion criteria were previous surgery (other than knee arthroscopy) on the affected site, a diagnosis of inflammatory arthritis, immunosu-pressed patients, a previous history of infection around the knee, smoking, diabetic patients. Applying these criteria we excluded a further sixty-seven patients.

The remaining 144 patients were separated in to two groups. Group I (n=54) consisted of those patients that received one or more recorded I/A steroid injections in their operated knee in an orthopaedic clinic, rheumatology clinic or general practice setting prior to surgery. Group II (n=90) consisted of those patients with no record of receiving an I/A steroid injection prior to surgery.

Results: We found that all the deep infections (3) were from Group I and had received an I/A steroid injection up to 11 months prior to surgery. The incidence of superficial infection was not significantly different from the control group (Group II).

In addition to those patients with confirmed deep infections, five patients underwent post-operative investigations for suspected deep infection, due to symptoms of persistent swelling or pain. All had received an I/A steroid injection pre-operatively.

The length of time between injection and subsequent post-operative infection leads us to speculate that the steroid agent might not fully dissolve, becoming trapped within the soft tissues or cystic areas of degeneration in the knee joint. Such steroids may become re-activated during operation, leading to catastrophic results. Indeed, there is experimental evidence to suggest an increased risk of infection with the intra-operative administration of steroids.

Conclusion: We conclude that the decision to administer intra-articular steroids to a patient who may be a candidate for knee replacement surgery should not be taken lightly because of a risk of post operative deep infection.

Introduction and Aims: Polyethylene wear and associated osteolysis is a major factor limiting arthroplasty longevity. The Duration process has the theoretical advantage of reducing wear. Our aim was to evaluate the wear rate of standard and Duration polyethylene using either metal or zirconia ceramic heads in the Anatomique Benoist Girard II hip system.

Method: Of 510 patients, 258 had appropriate radiographs for wear measurement. There were five bearing-couple groups. Group 1, 73 patients: metal (cobalt chrome) head on standard polyethylene; group 2, 73 patients: metal head on Duration polyethylene; group 3, 21 patients: (HIPed) zirconia ceramic head on standard polyethylene; group 4, 63 patients: HIPed zirconia head on Duration polyethylene; and group 5, 28 patients: non-HIPed zirconia head on standard polyethylene. All patients had 28mm heads. Sequential radiographs – at least one year after surgery and at least two years apart thereafter – were digitally scanned and images were analysed using computer software.

Results: Group 1: metal on standard polyethylene (n=73) – mean linear wear rate of 0.138 mm/yr (range 0.023–0.462 mm/yr). Group 2: metal on Duration polyethylene (n=73) – mean linear wear rate of 0.106 mm/yr (range 0.067–0.405 mm/yr). Group 3: HIPed zirconia heads on standard polyethylene (n=21) – mean linear wear rate of 0.124 mm/yr (range 0.037–0.225 mm/yr). Group 4: HIPed zirconia heads on Duration polyethylene (n=63) – mean linear wear rate of 0.120 mm/yr (range 0.001–0.427 mm/yr). Group 5: non-HIPed zirconia heads on standard polyethylene (n=28) – mean linear wear rate of 0.119 mm/yr (range 0.044–0.0330 mm/yr). Comparison of linear wear rates of standard (group 1) and Duration polyethylene (group 2) bearings with metal heads revealed a difference of statistical significance (p=0.0083), with lower annual wear rates with Duration polyethylene. Further comparison between these two groups revealed a male preponderance in the Duration group (p=0.000001). There was also a statistically significant difference in body weight between these groups, with the Duration group being heavier by a mean of 5.1 kilograms (p=0.05). There was no significant difference in wear rates between standard and Duration polyethylene bearings with HIPed zirconia heads. There was no statistically significant difference in age in our patient groups.

Conclusion: Duration polyethylene has lower linear wear rates when coupled with a cobalt chrome head. This is despite a male preponderance and higher body weight. Wear rates between standard and Duration polyethylene bearings coupled with zirconia heads were not statistically different.

Introduction This study was performed to evaluate the wear rates of Zirconia ceramic heads manufactured prior to the introduction of hot isostatic pressing, on a modular cementless polyethylene cup, and to compare this with the wear rate of a cobalt chrome head coupled with the same cup.

Methods Radiological analysis of 281 primary uncemented ABG total hip arthroplasties performed between 1991 and 1994 was carried out. Patients were divided into three groups: 203 patients with 28 mm zirconia head/polyethylene bearings, 47 patients with 32 mm zirconia ceramic head/polyethylene bearings, 31 patients with 28 mm cobalt chrome head/polyethylene bearings. Wear analysis was performed using the Martel software after digitising radiographs on a flatbed scanner. Initial radiographs were at a minimum of one year to exclude bedding in, and follow-up radiographs a minimum of two years later. Mean follow-up was 6.5 years.

Results The mean linear wear rate of the groups following age and gender matching: for 28 mm Zirconia heads 0.22 mm/yr, for 32 mm Zirconia heads 0.20 mm/yr and for 28 mm metal heads 0.14 mm/yr (p< 0.05). The patients with Zirconia heads had higher rates of osteolysis and revision than those with cobalt chrome heads.

Conclusions The reason for this increased wear rate of Zirconia on polyethylene may well be the transformation of the tetragonal stable phase of the Zirconia to the monolithic unstable phase on the surface of the material. This transformation at grain boundaries on the surface results in ceramic grain “pull-out” by the sliding action of the head against the polyethylene cup. This phenomenon may well occur as a result of the Zirconia processing; the ceramic studied was produced prior to hot isostatic pressing, which produces an inherently more stable ceramic i.e. a higher percentage of the tetragonal phase.

In relation to the conduct of this study, one or more of the authors is in receipt of a research grant from a non-commercial source.