Measurement of joint effusion and haematoma formation by ultrasound in assessing the effectiveness of drains after total knee replacement: A prospective randomised study.

We prospectively randomised 78 patients into two groups, 'drains' or 'no drains' to assess the effectiveness of suction drains in reducing haematoma and effusion in the joint and its effect on wound healing after total knee replacement. Ultrasound was used to measure the formation of haematoma and effusion on the fourth post-operative day. This was a semi-quantitative assessment of volume estimation. There was no difference in the mean effusion between the groups (5.91 mm in the drain group versus 6.08 mm in the no-drain, p = 0.82). The mean amount of haematoma in the no-drain group was greater (11.07 mm versus 8.41 mm, p = 0.03). However, this was not clinically significant judged by the lack of difference in the mean reduction in the post-operative haemoglobin between the groups (drain group 3.4 g/dl; no-drain group 3.0 g/dl, p = 0.38). There were no cases of wound infection or problems with wound healing at six weeks in any patient. Our findings indicate that drains do not reduce joint effusion but do reduce haematoma formation. They have no effect on wound healing.

Transient osteoporosis of the knee following trauma.

Transient osteoporosis is an uncommon, self-limiting, reversible condition. We report a case involving the knee following trauma. The aetiology is unknown, but the association between transient osteoporosis and trauma has not been documented previously. The clinical presentation represents a degree of overlap among various clinical syndromes, including reflex sympathetic dystrophy and avascular necrosis. The diagnosis was confirmed by bone scan and MRI. The patient, a 47-year-old man, was treated with non-steroidal anti-inflammatory medication, protected weight-bearing and physiotherapy. He made a full clinical recovery and bone quality returned to virtual normality.

Torsion of an intra-articular lipoma as a cause of pseudo locking of the knee.

We describe a case of a painful locked knee caused by the torsion of an intra-articular lipoma and review the literature on this unusual condition. There are many cases of locked knee and of intra-articular lipoma but to our knowledge there are no previous documented cases of a torted lipoma being identified as a cause of locking.

Current cementing techniques in hip hemi-arthroplasty.

To assess the use of modern cementing techniques in hip hemi-arthroplasty a postal questionnaire was sent during 1998 to all British Orthopaedic Training Association (B.O.T.A.) members regarding use of cement, type of cement, bone preparation and cementing technique. The results of this survey were compared to a similar survey in 1994 to assess any change in practice. Two hundred and eighty-six trainees responded to the 1998 survey, 352 to the 1994 survey. The use of uncemented prostheses had decreased from 31.3 in 1994 to 21.7% in 1998. Normal viscosity Palacos cement remains the most common cement in use, 64.3% in 1998. The use of antibiotic loaded cement has increased from 53.7 in 1994 to 67.9% in 1998. For bone preparation 47.3% of trainees in 1998 used a modern technique (syringe irrigation/pulsed lavage, brushing, gauze packing) compared to 35.1% in 1994. Modern cement insertion (retrograde gun, cement restriction and sustained pressure) was carried out by 39.3% in 1998 compared to 28.5% in 1994. Overall 27.2% of trainees used modern cementing techniques in hip hemi-arthroplasty, compared to 19.4% in 1994. Modern cementing techniques are used by a minority of British orthopaedic trainees, but in comparison to 1994 their use has increased.

Treatment for displaced intracapsular fracture of the proximal femur. A prospective, randomised trial in patients aged 65 to 79 years.

We performed a prospective, randomised trial comparing three treatments for displaced intracapsular fractures of the hip in 280 patients aged 65 to 79 years. The mean patient survival was significantly higher in the group undergoing reduction and internal fixation (79 months) compared with that with a cemented Thompson hemiarthroplasty or a cemented Monk bipolar hemiarthroplasty (61 months and 68 months, respectively). After three years, 32 of 93 patients (34.4%) who had undergone fixation had local complications, necessitating further intervention in 28 (30%). There were no significant differences in the functional outcome in survivors, who were reviewed annually to five years. Either reduction and internal fixation or cemented hemiarthroplasty may be offered as alternative treatments for a displaced intracapsular fracture in a mobile and mentally competent patient under the age of 80 years. The choice of procedure by the patient and the surgeon should be determined by the realisation that the use of internal fixation is associated with a 30% risk of failure requiring further surgery. If this is accepted, however, hemiarthroplasty is avoided, which, in our study has a significantly shorter mean survival time. The use of a bipolar prosthesis has no significant advantage.

Broken arrow: a complication of meniscal repair.

A case is reported in which a biodegradable arrow, used for arthroscopic meniscal repair, broke and migrated from the back to the front of the knee. Further surgery was necessary to remove the broken fragment. The concept of this sort of repair device is appealing as it may overcome some of the difficulties of suture repair techniques for posterior meniscal tears. However, surgeons should be aware that such devices can break and that the fragment may migrate. Questions over the shearing and bending strength, and the fixation of these devices should be addressed.

Sectioning fresh human bone: the reduction of aerosol and physical hazards.

Musculoskeletal research demands an accurate model on which to work, and fresh frozen human bone is an ideal material. However, there is increasing concern over the biohazard that this represents. A method is reported that reduces the biohazard, and two research situations are described. Both use polymethylmethacrylate (PMMA) bone cement as an interface between the human tissue and the cutting device, which allows solid and suitable geometry for vice fixation. A method of bone cutting that enables remote operation is described; this method may reduce the risk of disease transmission by aerosol, and prove useful to all in this field of research.

Unipolar or bipolar prosthesis for displaced intracapsular hip fracture in octogenarians: a randomised prospective study.

We performed a randomised prospective trial to compare a cemented unipolar prosthesis (Thompson) with a cemented bipolar prosthesis (Monk) in the treatment of displaced intracapsular fractures of the hip in patients over 80 years of age. Patients with a mental test score of less than 5/13 were excluded but the mortality was still about 30% at one year in both groups. We therefore feel that subjective criteria such as the level of pain and the return to the preinjury state are of paramount importance. Two years after operation there was no statistical difference between the rate of complications in the two groups. After adjusting for confounding factors such as differences in the level of function before injury between the groups, the degree of return to the preinjury state was significantly greater (p = 0.04) when using the unipolar prosthesis, which is one-quarter of the price of the bipolar. We cannot therefore justify the use of an expensive bipolar prosthesis in patients over 80 years of age.

Single-photon-emission computerised tomography compared with planar bone scan to assess femoral head vascularity.

We performed single-photon-emission CT (SPECT) and planar bone scans to assess femoral head vascularity in ten patients with displaced intracapsular hip fracture. The heads were labelled with tetracycline and after excision at hemiarthroplasty were assessed for tetracycline uptake distribution by fluorescence under UV light. The four which had the greatest tetracycline uptake were normal on SPECT and planar imaging. In two cases the planar bone scans were normal although SPECT suggested avascularity thus giving false-negative results. Surgeons should be aware of this; SPECT may prove to be a more accurate method of assessing vascularity of the femoral head in fractures of the femoral neck.

A subjective health indicator for follow-up. A randomised trial after treatment of displaced intracapsular hip fractures.

We report a randomised prospective trial of the early results of three types of treatment for displaced intracapsular hip fractures. We used a questionnaire sent to patients at about six months (Nottingham Health Profile, NHP) in addition to clinical assessments. There was a 67.4% usable response to the questionnaire, similar to that in other studies using the NHP. There were more responders from younger patients, those walking independently before injury and those with higher mental test scores on admission. In the younger group (65 to 79 years) we found a trend for better scores in most NHP indices after the use of a bipolar prosthesis rather than a unipolar prosthesis or internal fixation, particularly for social function, pain and physical mobility. Postal assessment using the NHP gave a satisfactory response rate even in the elderly, and can provide an extra assessment to complement or replace hospital follow-up in some circumstances.

Reduction of temperatures generated by the triple reamer within the femoral head.

The triple reamer is a convenient tool for reaming the proximal femur when using a sliding screw and plate device, but unnecessarily high temperatures may be generated within the femoral head while the lateral cortex is being reamed. Nineteen female patients over 60 years old were randomized to either the standard or a modified reaming technique with the triple reamer during internal fixation of proximal femoral fractures. Temperatures generated within the femoral head were measured. Results showed a mean peak temperature of 51.9 degrees C (range 42-66) using the standard method and 46.3 degrees C (range 40-52) using the modified method (P = 0.07). A significant difference (P < 0.05) was found in the duration of temperature elevation above the critical 44 degrees C (17.4s vs 5.7s), it being prolonged in the standard group. Even in this osteoporotic patient group, damaging temperatures which may contribute to the mechanical failure of fixation, are generated within the femoral head. A simple method to avoid this problem is described.