Patient-specific instruments: advantages and pitfalls.

Patient-specific instruments (PSI) aim to improve the accuracy of total knee replacement (TKR) based on computer-assisted preoperative planning. In this work, the authors describe the advantages and pitfalls of PSI based on their clinical experience. The main conclusion of this work is that PSI has direct impact on the logistical and technical features of TKR with some advantages and pitfalls.

The importance of early diagnosis in spontaneous osteonecrosis of the knee - A case series with six year follow-up.

Background: Spontaneous osteonecrosis of the knee has an unknown aetiology. Management options include conservative, surgical and pharmacological interventions. The aim of this study was to report the experience of the authors in conservative management of SONK using non-operative measures by analysing the functional outcome and need for surgical intervention.

Cartilage repair using autologous chondrocyte implantation techniques.

Articular cartilage in adults has a poor ability to self-repair after injury. A variety of cartilage resurfacing techniques have the potential to improve the repair of cartilage defects and reduce the patient's disability. The most advanced of these techniques is autologous chondrocyte implantation.

Composite ceramic bone graft substitute in the treatment of locally aggressive benign bone tumours.

Purpose: To report the use of a composite ceramic bone graft substitute containing calcium sulphate and hydroxyapatite (HA) in the treatment of large expansive osteolytic benign bone tumours.

Methods: 4 women and 9 men aged 8 to 49 (mean, 22) years with aneurysmal bone cysts (n=6) or giant cell tumours (n=7) in the epi- or meta-physeal areas of the lower limbs underwent curettage, phenolisation, and filling with bone graft substitute containing calcium sulphate and HA. The mean tumour size was 38.

Sacral insufficiency fractures.

Purpose: To highlight difficulties in the diagnostic process and the validity of imaging techniques for sacral insufficiency fractures.

Methods: Records of 25 women aged 68 to 95 years with sacral insufficiency fractures were reviewed. Baseline blood biochemistry and haematology test results were obtained.

Minimally invasive surgery of the knee.

Minimally invasive knee replacement surgery has been developed in an attempt to lessen the impact of operations on the patient's quality of life, in the same way as arthroscopy, the forefather of minimally invasive surgery (MIS), revolutionised cartilage and ligament surgery three decades earlier. The technique is based on minimising soft tissue and muscle trauma, skin incision length, and capsular disruption while trying to maintain the ultimate goal of a well-aligned, well-fixed knee replacement. Short-term advantages including accelerated recovery and reduction in blood loss have been demonstrated, but it remains to be investigated whether MIS is able to provide sustainable benefits and long-term outcome equivalent to conventional surgery.

Use of a novel bone graft substitute in peri-articular bone tumours of the knee.

We treated three patients with aneurysmal bone cysts and seven with giant cell tumours who presented with a large osteolytic lesion in peri-articular areas of the knee. The patients age ranged from 8 to 49 years (mean 25 years). The average tumour volume was measured at 39.

Should we use a separate knife for the skin?

The aim of this study was to re-assess whether the use of a 'one-knife technique' can be considered as safe as the alternative practice of using separate skin and inside knives for elective orthopaedic surgery. A total of 609 knife blades from 203 elective orthopaedic operations, with equal numbers of skin, inside and control blades, were cultured using direct and enrichment media. We found 31 skin blades (15.

Intra-articular protrusion of malpositioned Transfix implant following anterior cruciate ligament reconstruction.

We report on a case of stiffness of the knee following reconstruction of the anterior cruciate ligament caused by a Transfix implant (Manufacturer, City, State) protruding into the medial retinacular area. After a skiing injury, a 56-year-old woman had a complete rupture of the anterior cruciate ligament along with a tear of the medial collateral ligament. She had an immediate anterior cruciate ligament reconstruction.

Post-thrombotic syndrome after total hip or knee arthroplasty: incidence in patients with asymptomatic deep venous thrombosis.

Purpose: To measure the risk of developing signs of post-thrombotic syndrome 15 to 24 months after total hip or knee arthroplasty in patients with asymptomatic deep venous thrombosis (DVT).

Methods: A total of 85 total knee arthroplasty patients and 47 total hip arthroplasty patients were postoperatively screened for asymptomatic DVT using colour duplex ultrasound.

Results: The rate of asymptomatic DVT was 37.

Suction dressings in total knee arthroplasty--an alternative to deep suction drainage.

A new technique is described for dressing of surgical wounds in total knee arthroplasty that is a combination of a semi-permeable dressing and suction drainage. This technique has been used in 100 consecutive cases and drainage was collected in 92. The average volume was 198 ml (range 30 to 850 ml).

Transient osteoporosis of the knee.

We report 12 cases of transient osteoporosis in 10 patients. The presenting symptoms, diagnostic investigations and management are considered here as well as a discussion on the aetiology and the pathology. Arthroscopic surgery was carried out in some of the patients to exclude intraarticular pathology.

Sciatic nerve injury following hamstring harvest.

Injury to the sciatic nerve following harvesting of the medial hamstring tendons is a complication that has not been described. I report a unique case of sciatic nerve injury above the level of its bifurcation into its terminal branches following hamstring graft harvest for use in ACL reconstruction. The sciatic nerve anatomy and technique of graft harvest is briefly described.

Displacement of the common peroneal nerve associated with upper tibial fracture: implications for fine wire fixation.

The constant anatomic position of the common peroneal nerve is relied on when performing fine wire external fixation in the upper tibia. We report the case of a sixty-two-year-old woman with a Schatzker Type V fracture of her right tibial plateau and upper-third diaphyseal fracture associated with displacement and shortening of the upper tibia. She was treated by minimal internal fixation of the intraarticular fracture and application of a Sheffield Hybrid External Fixator.

Suction dressings: a new surgical dressing technique.

A new technique in surgical dressing is described which is a combination of a semi-permeable dressing and suction drainage. This dressing has been used successfully in 20 orthopaedic patients without any wound complication and with satisfactory comfort to the patient. This form of post-operative wound management appears to retain the nursing and hygiene advantages of suction drainage, whilst avoiding the patient discomfort and the possibilities of wound infection, associated with deep internal drainage.

A technique for prevention of sudden pressure loss on emptying of irrigation bags during arthroscopic surgery using gravity-fed irrigation systems.

Gravity-fed irrigation systems in arthroscopic surgery are safe and cheap, but visualization can be impaired by fluctuations in in-flow pressure, which leads to bleeding and temporary disruption of surgery. We describe a gravity-fed irrigation system using differential hydrostatic pressures in sequentially arranged irrigation bags that can be independently raised and lowered. This technique maintains a relatively steady flow and intra-articular pressure, thereby improving the quality of irrigation without having to resort to the more expensive pressure infusion systems, and minimizing the need for surgery under tourniquet.

An arthroscopic technique of demonstrating the pathomechanics of the suprapatellar plica.

The suprapatellar plica or incomplete suprapatellar septum of the knee is a recognized cause of knee pain in some patients and appears to exist in others without causing any symptoms. To date no clear method of demonstrating the pathomechanics of the suprapatellar plica by arthroscopic means has been described. This article describes a new technique of visualizing this structure arthroscopically and demonstrating the mechanism of its morbidity.