This study evaluates factors related to myelopathic symptoms in patients with ossification of the posterior longitudinal ligament (OPLL). A total of 87 patients with OPLL were included. Of these, 53 (Group I) had no symptoms or presented with neck pain and radiculopathy and 34 (Group II) had myelopathic symptoms. Gender, age, and history of trauma were evaluated in the two groups. The range of movement of the cervical spine was measured using plain radiographs. The number of involved segments, type of OPLL, and maximal compression ratio were analysed using CT and signal change in the spinal cord was evaluated using MRI.

The patients’ age was found to be significant (p = 0.001). No difference was found between gender and the range of movement in the two groups. The maximum compression of the spinal canal showed a difference (p = 0.03). The signal change of the spinal cord was different between the two groups. In patients with OPLL of the cervical spine, myelopathic symptoms are not related to the range of movement or the number of involved segments.

Based on the constancy with which the limbus is inverted into the joint in a typical congenital dislocation of the hip, a hypothesis is presented which suggests that the sequence of events leading to established dislocation is: 1) lateral rotation aided and abetted by anteversion; 2) extension of the hips causing subluxation; 3) dislocation and inversion of the limbus; 4) secondary changes in the upper end of the femur, pelvis and acetabulum which will also develop if the deformity does not progress beyond a subluxation.

A pen picture is drawn showing how anteversion is either moulded away during growth to produce a normal hip, or persists with or without dislocation. The fate of the persistently inverted limbus is discussed and a line of treatment based on these findings is briefly considered.

Objectives

Rotator cuff tears are among the most common and debilitating upper extremity injuries. Chronic cuff tears result in atrophy and an infiltration of fat into the muscle, a condition commonly referred to as ‘fatty degeneration’. While stem cell therapies hold promise for the treatment of cuff tears, a suitable immunodeficient animal model that could be used to study human or other xenograft-based therapies for the treatment of rotator cuff injuries had not previously been identified.

We developed a questionnaire to assess patient-reported outcome after surgery of the elbow from interviews with patients. Initially, 17 possible items with five response options were included. A prospective study of 104 patients (107 elbow operations) was carried out to analyse the underlying factor structure, dimensionality, internal and test-retest reliability, construct validity and responsiveness of the questionnaire items. This was compared with the Mayo Elbow performance score clinical scale, the Disabilities of the Arm, Shoulder and Hand questionnaire, and the Short-Form (SF-36) General Health Survey. In total, five questions were considered inappropriate, which resulted in the final 12-item questionnaire, which has been referred to as the Oxford elbow score. This comprises three unidimensional domains, ‘elbow function’, ‘pain’ and ‘social-psychological’; with each domain comprising four items with good measurement properties.

This new 12-item Oxford elbow score is a valid measure of the outcome of surgery of the elbow.

In order to identify the risk factors and the incidence of post-operative spinal epidural haematoma, we analysed the records of 14 932 patients undergoing spinal surgery between 1984 and 2002. Of these, 32 (0.2%) required re-operation within one week of the initial procedure and had an International Classification of Diseases (ICD)-9 code for haematoma complicating a procedure (998.12). As controls, we selected those who had undergone a procedure of equal complexity by the same surgeon but who had not developed this complication. Risks identified before operation were older than 60 years of age, the use of pre-operative non-steroidal anti-inflammatories and Rh-positive blood type. Those during the procedure were involvement of more than five operative levels, a haemoglobin < 10 g/dL, and blood loss > 1 L, and after operation an international normalised ratio > 2.0 within the first 48 hours. All these were identified as significant (p < 0.03). Well-controlled anticoagulation and the use of drains were not associated with an increased risk of post-operative spinal epidural haematoma.

Degenerative spondylolisthesis is most common at the L4/L5 level and in women. There are several possible reasons for its predilection at this site, but there is no satisfactory explanation for the predominance in women. We considered that pregnancy was a possible influence.

We reviewed the records and radiographs of 949 women and 120 men aged 50 years and over who had attended a spinal surgeon for low back pain over a five-year period. We found that women who had borne children had a significantly higher incidence of degenerative spondylolisthesis than nulliparous women (28% v 16.7%; p = 0.043). The men had a 7.5% incidence, significantly less than nulliparous women (p = 0.031). Our results suggest that pregnancy is an important factor in the aetiology of degenerative spondylolisthesis.

Aims

The aim of the study was to develop a quantitative scoring system to predict whether a large-to-massive rotator cuff tear was arthroscopically reparable prior to surgery.

The primary aim of this study was to develop a patient-reported Activity & Participation Questionnaire (the OKS-APQ) to supplement the Oxford knee score, in order to assess higher levels of activity and participation. The generation of items for the questionnaire involved interviews with 26 patients. Psychometric analysis (exploratory and confirmatory factor analysis and Rasch analysis) guided the reduction of items and the generation of a scale within a prospective study of 122 relatively young patients (mean age 61.5 years (42 to 71)) prior to knee replacement. A total of 99, completed pre-operative and six month post-operative assessments (new items, OKS, Short-Form 36 and American Knee Society Score).

The eight-item OKS-APQ scale is unidimensional, reliable (Cronbach’s alpha 0.85; intraclass correlation coefficient (ICC) 0.79; or 0.92 when one outlier was excluded), valid (r >  0.5 with related scales) and responsive (effect size 4.16).

We recommend that it is used with the OKS with adults of all ages when further detail regarding the levels of activity and participation of a patient is required.

Cite this article: Bone Joint J 2014;96-B:332–8.

It is becoming increasingly common for a patient to have ipsilateral hip and knee replacements. The inter-prosthetic (IP) distance, the distance between the tips of hip and knee prostheses, has been thought to be associated with an increased risk of IP fracture. Small gap distances are generally assumed to act as stress risers, although there is no real biomechanical evidence to support this.

The purpose of this study was to evaluate the influence of IP distance, cortical thickness and bone mineral density on the likelihood of an IP femoral fracture.

A total of 18 human femur specimens were randomised into three groups by bone density and cortical thickness. For each group, a defined IP distance of 35 mm, 80 mm or 160 mm was created by choosing the appropriate lengths of component. The maximum fracture strength was determined using a four-point bending test.

The fracture force of all three groups was similar (p = 0.498). There was a highly significant correlation between the cortical area and the fracture strength (r = 0.804, p <  0.001), whereas bone density showed no influence.

This study suggests that the IP distance has little influence on fracture strength in IP femoral fractures: the thickness of the cortex seems to be the decisive factor.

Cite this article: Bone Joint J 2014;96-B:1378–84.

We used prospective data from 862 total knee and 716 total hip replacements three years after surgery in order to derive and validate a reduced Western Ontario and McMasters University Osteoarthritis Index (WOMAC) function scale. The reduced scale was derived using the advice of clinical experts as well as analysis of data. The scale was tested for validity, reliability and responsiveness.

Items which were retained included: ascending stairs, rising from sitting, walking on the flat, getting in or out of a car, putting on socks, rising from bed, and sitting.

The reduced and full scales had comparable, moderate correlations with other measures of function, confirming convergent validity. Cronbach’s alpha was high (α > 0.85) with the reduced scale confirming reliability. Responsiveness was greater for the reduced scale (full = 1.4, reduced = 1.6).

This reduced version of the WOMAC function scale provides a practical, valid, reliable and responsive alternative to the full function scale for use after total joint replacement. Further work is needed to demonstrate its wider applicability.

The success of long-term transcutaneous implants depends on dermal attachment to prevent downgrowth of the epithelium and infection. Hydroxyapatite (HA) coatings and fibronectin (Fn) have independently been shown to regulate fibroblast activity and improve attachment. In an attempt to enhance this phenomenon we adsorbed Fn onto HA-coated substrates. Our study was designed to test the hypothesis that adsorption of Fn onto HA produces a surface that will increase the attachment of dermal fibroblasts better than HA alone or titanium alloy controls.

Iodinated Fn was used to investigate the durability of the protein coating and a bioassay using human dermal fibroblasts was performed to assess the effects of the coating on cell attachment. Cell attachment data were compared with those for HA alone and titanium alloy controls at one, four and 24 hours. Protein attachment peaked within one hour of incubation and the maximum binding efficiency was achieved with an initial droplet of 1000 ng. We showed that after 24 hours one-fifth of the initial Fn coating remained on the substrates, and this resulted in a significant, three-, four-, and sevenfold increase in dermal fibroblast attachment strength compared to uncoated controls at one, four and 24 hours, respectively.

Recent reports have suggested an association between Perthes’ disease and an underlying thrombophilic or hypofibrinolytic tendency. In Northern Ireland there is a high incidence of Perthes’ disease (11.7 per 100 000 or 1 in 607 children) in a stable paediatric population.

We reviewed 139 children with Perthes’ disease and compared them with a control group of 220 aged- and gender-matched healthy primary schoolchildren with similar racial and ethnic backgrounds.

There were no significant deficiencies of antithrombotic factors protein C, protein S, antithrombin III or resistance to activated protein C. A total of 53 (38.1%) of the children with Perthes’ disease had a prolonged activated partial thromboplastin time (> 38) compared with 13 (5.9%) of the control group (p < 0.001). Our findings have shown that using standard assays, thrombophilia secondary to antithrombotic factor deficiency or resistance to activated protein does not appear to be an aetiological factor for Perthes’ disease. The cause of the prolonged activated partial thromboplastin time, usually associated with a clotting factor deficiency, is under further investigation.

1. The difficulties of obtaining myo-electric signals from the muscles in amputation stumps are discussed.

2. The requirements of a myo-telemetry system which could be implanted are discussed.

3. A description is given of a new approach to the problem in which the electrical unit is contained in an inert plastic and fitted into the bone in the amputation stump, using an external power source.

1. Orthotic systems for the upper limb are described.

2. Two patients are described to illustrate the value of the systems.

We studied the possible role of melatonin deficiency in experimentally-induced scoliosis. A total of 90 chickens underwent pinealectomy on the third day after hatching: 30 were treated with serotonin, 30 with melatonin and 30 received no therapy (control group). Scoliosis developed in all the control group, in 22 of the serotonin group, and in only 6 of the melatonin group. The six melatonin-treated chickens with scoliosis had less severe spinal deformities than those in the serotonin-treated group. There were lower blood melatonin concentrations in chickens with scoliosis than in those without. Our findings suggest that melatonin deficiency contributes to the aetiology of this experimental scoliosis, probably by interfering with the normally symmetrical growth of the proprioceptive system involving the paraspinal muscles and the spine.