Re-attachment of the tuberosities of the humerus following hemiarthroplasty for four-part fracture.

This study evaluated the effect on movement under load of three different techniques for re-attachment of the tuberosities of the humerus using test sawbones. In the first, the tuberosities were attached both to the shaft and to each other, with one cerclage suture through the anterior hole in the prosthesis. The second technique was identical except for omission of the cerclage suture and in the third the tuberosities were attached to the prosthesis and to the shaft. An orthogonal photogrammetric system allowed all segments to be tracked in a 3D axis system. The humeri were incrementally-loaded in abduction, and the 3D linear and angular movements of all segments were calculated. Displacement between the tuberosities and the shaft was measured. The first and second techniques were the most stable constructs, with the third allowing greater separation of fragments and angular movement. Separation at the midpoint of the tuberosities was significantly greater using the latter technique (p < 0.05). The cerclage suture added no further stability to the fixation.

Evaluation of the long intra-medullary hip screw.

There have been many publications about second generation femoral nails, such as the Russell-Taylor nail (Smith & Nephew Richards, Memphis, TN, USA) and Long Gamma Nail (Howmedica, Rutherford, NJ, USA), but little work has been published on the Long Intra-medullary Hip Screw (IMHS, Smith & Nephew). We set out to evaluate the effectiveness of the Long IMHS as a device for the fixation of proximal femoral fractures. We retrospectively reviewed 30 patients who had a Long IMHS inserted for a sub-trochanteric or proximal femoral fracture. Of the 30 patients, three had died and six were lost to follow up, leaving 21, whom we reviewed. Of the 21 patients reviewed the mean age was 67 years and the mean follow up was 31 weeks. Mean time to union was 15.65 weeks, with one non-union. There were three superficial wound infections. In one patient there was loosening of the distal locking screws, requiring removal and there was one case of intra-operative femoral shaft fracture. We conclude that, the Long IMHS is an effective device for the treatment of sub-trochanteric and proximal femoral fractures with a high rate of union achieved and a low complication rate.

Direct comparison of calculated hip joint contact forces with those measured using instrumented implants. An evaluation of a three-dimensional mathematical model of the lower limb.

Characterisation of hip joint contact forces is essential for the definition of hip joint prosthesis design requirements. In vivo hip joint contact force measurements have been made using instrumented hip joint prostheses. However, to allow determination of the range of values of joint contact force and their directions relative to anatomical structures in a range of subject groups sufficient to form an agreed data base it is necessary to adopt a different approach without the use of an implanted transducer. The use of mathematical models of the lower limb to examine the forces in soft tissues and at the joints has provided valuable insight into internal loading conditions. Several authors have proposed mathematical musculo-skeletal models. However, there have been only limited attempts at validation of these models. It is possible to use the results of in vivo force measurements from instrumented prostheses to validate the results calculated using the mathematical models. In this study two subjects with instrumented hip joint prostheses were studied. Forces at the hip joints were calculated using a three-dimensional model of the leg. Walking at slow, normal and fast speeds (0.97-2.01m/s), weight transfer from two to one leg and back again, and sit to stand were studied. Direct comparisons were made between the 'gold standard' measured hip joint contact forces and the calculated forces. There was general agreement between the calculated and measured forces in both pattern and magnitude. There were, however, discrepancies. Reasons for these differences in results are discussed and possible model developments suggested.

Does shortening matter after clavicular fractures?

Healing of clavicular fractures with shortening of 15 mm or more has been associated with poor function and open reduction and internal fixation has been recommended as the appropriate initial treatment. We studied 41 patients at least three months after clavicular fracture. Clavicular shortening was calculated and shoulder function was assessed using the Constant Scoring method. Although three patients with shortening of 1.5 cm or more had low scores, this could be attributed to other factors. We could not demonstrate any relationship between clavicular shortening and shoulder function.

Total shoulder replacement in rheumatoid disease: 7- to 13-year follow-up of 37 joints.

We made a prospective study of 58 consecutive Neer II total shoulder replacements in 49 rheumatoid patients. Cemented glenoid and press-fit humeral components had been used. After a mean follow-up of 9.5 years (7 to 13), 11 patients (15 shoulders) had died, one shoulder had been arthrodesed and five patients (five shoulders) had been lost to follow-up. Of the remaining 37 shoulders 29 were painfree or had only slight discomfort, four had pain on unusual activity, and four had moderate or severe pain. There were satisfactory improvements in the mean range of active elevation (53 degrees to 75 degrees) and external rotation (5 degrees to 38 degrees); satisfactory performance of the activities of daily living had been maintained throughout follow-up. Radiographs showed loosening in ten shoulders of nine glenoid and nine humeral components but of these only three had significant symptoms. Three loose glenoid components and two loose humeral components required revision. We consider that the Neer total shoulder replacement provides a reasonable medium to long-term outcome in rheumatoid arthritis, but recommend that the humeral component should be routinely cemented.

Three-dimensional joint co-ordination strategies of the upper limb during functional activities.

A triaxial flexible electrogoniometer has been developed to measure the three-dimensional angular motion of the shoulder joint during simulated activities of daily living. The motion of the elbow, forearm and wrist were also recorded and angle-angle diagrams were mathematically analysed to provide quantitative parameters regarding the control and co-ordination of the joints of the normal and the arthritic upper limb. Two parameters (slope and movement area quotient) were derived and used in the interpretation of joint motion during different activities.

Unconstrained shoulder arthroplasty in rheumatoid arthritis.

The shoulder complex is commonly involved in patients who have rheumatoid arthritis. Highly satisfactory results have been reported after shoulder arthroplasty in patients with rheumatoid arthritis. There is considerable variability in the pathology within the rheumatic glenohumeral joint. Four radiologic patterns have been identified that correlate well with the pathologic findings. The wet pattern is frequently associated with early rupture of the rotator cuff. Certain technical considerations that apply to the performance of shoulder arthroplasty in these patients are addressed herein. Despite early concerns about fixation of the glenoid component, a long-term study performed at the author's institution suggested that this was no greater a problem than loosening of the humeral component, signs of which are increasingly seen with lengthening followup. There is currently a trend toward use of humeral head replacements alone, which may be an acceptable form of management of the rheumatic glenohumeral joint.

The role of computerized tomography in shoulder arthrography.

Double contrast computerized tomographic (CT) shoulder arthrograms of 55 shoulders were reviewed. This investigation was compared with conventional arthrograms and the findings were correlated with subsequent clinical and surgical follow-up. CT arthrograms were found to be useful in demonstrating bony, ligamentous and cartilaginous structures and have helped the surgeon in deciding the approach and type of surgical procedure. Indications for CT arthrography are recurrent dislocation, multidirectional instability, severe rheumatoid arthritis and other arthritides, complex shoulder deformities and suspected loose bodies. We found that this examination was not as helpful for rotator cuff injuries, impingement syndrome, adhesive capsulitis and in cases of vague or mild shoulder pain.

The source of shoulder pain in rheumatoid arthritis: Usefulness of local anesthetic injections.

Clinical symptoms and radiologic appearances are often poor indicators of the source of pain in the shoulder joint complex in patients with rheumatoid arthritis. In 75 rheumatoid shoulders, injections of 1 ml of 1 % local anesthetic were placed in the acromioclavicular joint, the subacromial bursa, and the glenohumeral joint, following a standard sequence. Forty-one shoulders were relieved of pain from subacromial or acromioclavicular injections even when there were advanced radiologic changes in the glenohumeral joint. However, if the sphericity of the humeral head had been lost, an injection of the glenohumeral joint usually confirmed this site as the source of pain. The results of local anesthetic injections allow decisions to be made about the most appropriate form of surgical or nonsurgical treatment.

Extra-glenohumeral joint shoulder surgery in rheumatoid arthritis: The role of bursectomy, acromioplasty, and distal clavicle excision.

Twenty-four painful shoulders in patients with rheumatoid arthritis have been studied before and after extra-glenohumeral joint surgery. Preoperative local anesthetic injections were used to localize sites of pain and served as a basis for the surgical procedure performed. Radiographs were graded with the Larsen classification; 17 shoulders had radiographic evidence of advanced glenohumeral disease. Surgery included subacromial bursectomy, anterior acromioplasty, and excision of the outer end of the clavicle. At an average follow-up of 30 months (range 18 to 50 months) for 22 of the shoulders, 19 had minimal pain. Average motions improved in flexion from 68° to 121° and in external rotation from 23° to 52°. Two experienced infections, one superficial and one deep. One further operation has been necessary to treat the shoulder arthritis. Extra-glenohumeral joint surgery, planned according to the results of preoperative injection testing, has a useful role in management of the shoulder in rheumatoid arthritis, even when the glenohumeral joint is involved radiographically.

An investigation of occlusive polyester surgical clothing.

The bacterial dispersion rate of people wearing operating room clothing made from several types of polyester fabric was compared to conventional cotton clothing, total-body exhaust gowns and disposable clothing. Airborne bacteria were measured in a chamber, three ultra-clean air operating rooms and a conventionally ventilated operating room. The polyester clothing was demonstrated to be much superior to conventional cotton clothing and at least as good as the total-body exhaust gowns and disposable clothing.

Maximal isometric patellofemoral contact force in patients with anterior knee pain.

We assessed patellofemoral joint function by combining the measurement of maximal isometric extensor torque at the knee with clinical and radiological measurements in order to calculate the patellofemoral contact force. Eighteen volunteers established the normal ranges of results and the reliability of the system. Of the 39 patients with a variety of knee problems, 29 had anterior knee pain, and all had a subsequent arthroscopy. Patients with anterior knee pain and lesions in the patellar cartilage had significantly reduced isometric contact forces, but those with normal patellofemoral cartilage had normal contact forces. Our method may be useful in providing an objective assessment of anterior knee pain and a quantitative means of monitoring its treatment.

Flexible goniometer computer system for the assessment of hip function.

A new computer-based system has been developed to assess function in a clinical environment. Flexible electrogoniometers were used to record the motion of both hips and both knees in total hip replacement patients. Foot switches and instrumented walking aids were also incorporated, together with a fixed length timing facility for the derivation of walking velocity, stride length and cadence. The data can be presented on the computer screen immediately following the walking test in the form of angle/time or angle/angle graphs. This facility enables clinicians to study asymmetry and other abnormalities during the clinic session. A summary version of the data can thereafter be generated and included in the patient's notes. A total of 65 patients have been assessed prior to hip replacement and at 2, 6 and 12 months post-operatively. Following surgery, the patients exhibited significant improvments in range of motion, gait velocity and cadence but at 12 months post-operatively their functional performance was restricted compared to data collected for the normal subjects.

Radiographs in shoulder trauma.

It is difficult to establish the diagnosis of an injured shoulder if only one radiographic projection is used. We have compared two lateral projections, the Neer trans-scapular and the apical oblique in 80 patients; the radiographs were presented randomly to 10 casualty officers and nine radiologists. The apical oblique view was found to permit more accurate diagnosis of fractures and of dislocation by both groups.

Neer total shoulder replacement in rheumatoid arthritis.

Forty-two shoulders in 37 patients with polyarthritis were treated with Neer total shoulder replacements and reviewed 12 to 66 months afterwards. There was good pain relief and improvement in function, but the range of movement was less than that seen after replacements for osteoarthritis; this may have been related to the fact that 34 shoulders had abnormal rotator cuff tendons. Although there was a high incidence of radiolucent lines around the glenoid component, there was no clinical evidence of loosening. There were a few complications, but on the whole we feel that the Neer total shoulder arthroplasty is a valuable procedure for a patient with polyarthritis.