Variations in the MRI appearance of the insertion of the tendon of subscapularis.

Standard anatomical textbooks describe the insertion of the subscapularis tendon on to the lesser tuberosity of the humerus. The transverse humeral ligament is also described at this level, as a band of tissue attached to the greater and lesser tuberosities, overlying the long tendon of biceps as it emerges from the capsule of the shoulder joint. The shoulder is a notorious site for anatomical variation but until recently little has been published with regard to the tendon of subscapularis. In this study, we illustrate that considerable variation in the insertion site of the tendon of subscapularis can be demonstrated using magnetic resonance imaging and that only 20% conform to the classic textbook description. In addition, a distinct transverse humeral ligament was identifiable in only a minority of shoulders examined (36%).

A novel mechanism for induction of increased cortical porosity in cases of intracapsular hip fracture.

It has been suggested that, in hip fracture, the cortex on the inferoanterior (IA) to superoposterior (SP) axis is thinned and shows increased porosity. This is dependent on the presence of giant canals (i.e., diameter >385 microm), which are related to clusters of remodeling osteons. To investigate further the relationship between remodeling and bone loss, osteonal diameter (On.Dm), wall thickness (W.Th), osteoid width (O.Wi), and extent (OS) were measured in femoral neck biopsies from 12 female intracapsular hip fracture cases and 11 age- and gender-matched controls. Over 83% of giant canals were "composite" osteonal systems in which a single canal was surrounded by multiple packets of osteonal bone. Among smaller canals, over 80% of systems had a canal encircled by a single cement line containing one packet of bone ("simple"). Composites were nearly twice as prevalent in fractures (fracture cases 9.8 +/- 0.7/25 mm(2), controls 5.3 +/- 0.4/25 mm(2), p < 0. 0001), and were dependent (R(2) = 0.52) on femoral neck region (p = 0.0008) and the regional distribution of clusters of remodeling osteons (p = 0.0045). Both the inferior (I) and anterior (A) regions had an elevated number of composites (I: 263% of control values, p = 0.0054; A: 202% of control values, p = 0.0092). On.Dm was similar in fracture cases and controls (simple: fracture cases 183 +/- 3 microm, controls 191 +/- 4 microm; composites: fracture cases 446 +/- 13 microm, controls 460 +/- 13 microm). W.Th in simples was similar in fracture cases and controls (fracture cases 51 +/- 0.8 microm, controls 49 +/- 0.7 microm), but composites had significantly (p < 0. 0001) thinner walls, with the reduction in fracture cases (31%) being twice that of controls (12%, p < 0.0001). There were no differences in O.Wi. It was unusual for osteoid to fully surround the composite canal surface; OS was 38% lower in composite than simple canals (p < 0.0001). This study indicates that, in the femoral neck cortex, the principal remodeling deficit in hip fracture is specific to composite osteons. Hip fracture cases had zonal increases in composite osteon density with reduced bone formation. The data suggest that generation of composite osteons is a plausible mechanism leading to increasing porosity and trabecularization of the cortex, thus weakening the cortex in regions maximally loaded on fall impact.

An assessment of the effectiveness of magnetic resonance imaging of the shoulder: literature review.

OBJECTIVE: To analyse and compare all papers published to date (August 2000) that quantify the effectiveness, defined as the impact of clinician's diagnosis or management plans, or patient outcome, of MRI of the shoulder. DESIGN: A computerised search of Index Medicus with a broad search strategy relating to shoulder MRI was performed. Manual assessment of all papers listed was undertaken with classification of each paper depending on whether it addressed questions of (1) technical performance, (2) diagnostic performance or (3) outcome. RESULTS: Four of 265 qualifying papers addressed aspects of effectiveness and these were reviewed. The impact on the clinician's diagnosis varied widely between papers: the primary diagnosis was altered in 23% to 68% of cases, and the management plans were subsequently changed in 15% to 61% of cases. Only one paper addressed the impact on patient health. CONCLUSIONS: The effectiveness of MRI of the shoulder depends on the clinical skills of the referring clinician and prevalence of disease in the study population. This will have implications when the effectiveness of an imaging technique between different institutions is compared, and this in turn will influence any comparisons of cost-effectiveness.

Diagnostic and therapeutic impact of MRI and arthrography in the investigation of full-thickness rotator cuff tears.

Investigation of shoulder pain is important before surgical treatment. The presence or absence of a full-thickness rotator cuff tear (FTRCT) may determine the type of surgical treatment. Both MRI and conventional arthrography can be used, but little is known about their relative diagnostic and therapeutic impact. We performed a prospective trial assessing: (a) the influence of MRI and arthrography results on the clinician's diagnostic thinking (diagnostic impact); (b) the influence of the results on the clinician's therapeutic thinking (therapeutic impact); and (c) the diagnostic performance of the two techniques in patients with surgical confirmation. A total of 104 consecutive patients with shoulder problems referred to a specialist orthopaedic shoulder clinic underwent pre-operative investigation with MRI and arthrography. The surgeon's diagnosis, diagnostic confidence and planned treatment were measured before the investigation, and then again after the results of each investigation. Before the presentation of the investigation, results, the patients were randomised into two groups. In one group MRI was presented first; in the other group, arthrography. The MRI results led to fewer changes in diagnostic category (14 of 46, 30%) than arthrography (20 of 54, 37%), but the difference was not significant (P > 0.5). Magnetic resonance imaging led to slightly more changes in planned management (17 of 47, 36%) than arthrography (14 of 55, 25%), but again the difference was not statistically significant (P > 0.3). The results of the second investigation always had less diagnostic and therapeutic impact than the first. The accuracy of MRI for FTRCT in 38 patients with surgical confirmation was 79%, sensitivity 81% and specificity 78%; the accuracy of arthrography was 82%, sensitivity 50% and specificity 96%. The clinical diagnosis and management plan can be adequately defined by a single radiological investigation. Magnetic resonance imaging and arthrography had fairly similar diagnostic and therapeutic impact and comparable accuracy, although MRI was more sensitive and less specific. Magnetic resonance imaging may be the preferred investigation because of its better demonstration of soft tissue anatomy.

Imaging of the rotator cuff: an arthrographic pitfall.

We present a case where MRI and arthrography of the shoulder reports provided seemingly conflicting data. The subsequent findings at arthroscopy revealed a potential pitfall in arthrographic interpretation.

Magnetic resonance imaging or arthrography of the shoulder: which do patients prefer?

110 consecutive patients were asked about their degree of anxiety (SAI scores), pain (VAS scores) and preferences at various stages before and after imaging in order to determine whether patients with shoulder problems prefer MRI or shoulder arthrography. 88 patients underwent MRI, 42 arthrography and 19 both. Mean levels of anxiety were slightly higher for patients undergoing MRI than those having arthrography, but this difference was not statistically significant. There was a statistically significant (p < 0.03) reduction in anxiety after arthrography, but not following MRI. Pain scores fell for both patient groups while at rest during the imaging procedure compared with their pre-imaging baseline measurement. This was statistically significant (p < 0.03) for MRI, but not for arthrography. A significantly higher proportion (p < 0.001) of patients found MRI unpleasant or extremely unpleasant (20/77) compared with arthrography (3/41). Of the 25 patients who expressed a preference on the basis of past or current experience, 11 preferred MRI and 14 arthrography (NS). There was no significant difference in the proportion of patients who would not allow the test to be repeated (29/73 for MRI, 15/39 for arthrography): Although there were minor differences in both the anxiety and pain experienced by patients undergoing MRI and arthrography, this study did not reveal any firm preference for either investigation.

Magnetic resonance imaging of the shoulder: assessment of effectiveness.

OBJECTIVES: To quantify how magnetic resonance imaging (MRI) influences clinicians' diagnosis, diagnostic confidence and management plans in patients with shoulder problems. To investigate whether such changes are associated with an improvement in health. METHODS: A prospective observational study on all patients referred to a regional centre for MRI of the shoulder over a 6-month period. Data on diagnosis, diagnostic confidence and proposed management before MRI were compared with diagnoses and actual management after MRI. In addition, short form 36 item (SF-36) health survey data were collected at referral and again 6 months later. RESULTS: In 86 of 99 MRI referrals there was sufficient clinical data for the patient to enter the study. MRI led to previously unsuspected diagnoses in 20 of 59 patients where the clinicians had provided full diagnostic information before and after the examination. When MRI confirmed the clinical diagnosis, significant improvements in clinicians' diagnostic confidence were found (P < 0.001). MRI led to a change in management (P < 0.05) in 44 (62%) of the 71 patients where full management plans were available. Health survey results were available in 62 patients; although there were some improvements in SF-36 scores, these did not reach statistical significance. CONCLUSION: Magnetic resonance imaging of the shoulder significantly influences clinicians' diagnoses and management plans. However, patients do not record a statistically significant improvement in health-related quality of life over 6 months.

Prevalence and possible pathological significance of calcium phosphate salt accumulation in tendon matrix degeneration.

OBJECTIVES: To investigate the prevalence of calcium phosphate mineral salt accumulation in degenerative supraspinatus 'tendinitis' compared with a normal sample of human tendons, and to determine whether there is an association of calcium salt deposition with pathological changes in the tendon extracellular matrix. METHODS: Cadaver tendons (supraspinatus and common biceps tendons, n = 96) and fragments of supraspinatus tendons obtained during shoulder surgery (n = 31) were analysed for calcium content by atomic absorption spectroscopy, phosphorous content using a spectrophotometric assay, and matrix composition (collagen, glycosaminoglycans and DNA) using standard biochemical techniques. RESULTS: We established baseline values of calcium concentration in macroscopically normal cadaver tendons (mean 1.1 (SD 0.35) micrograms/mg dry wt, n = 60) and found that 33% (nine of 27) of ruptured tendons from patients with 'degenerative tendinitis' contained an excess of calcium (more than 2SD greater than the normal sample mean). Five of these specimens had increased concentrations of phosphorous and calcium:phosphorous (molar) ratios consistent with a variety of possible calcium crystals, including calcium pyrophosphate, hydroxyapatite, and tricalcium phosphate, in addition to mixed or amorphous calcium phosphate deposits. Four of these specimens contained normal concentrations of phosphorous, consistent with deposits of calcium oxalate or calcium carbonate, although this was not confirmed biochemically. In contrast, surgical specimens (n = 4) from patients with 'calcifying tendinitis' (radiographically detected calcium deposits) all contained salts with a mineral composition consistent with hydroxyapatite. The presence and identity of crystal deposits was subsequently confirmed in five specimens by radiographic microanalysis. Analysis of the tendon matrix demonstrated a number of significant differences between normal and degenerate (ruptured) tendons, including a reduction in collagen content, an increase in sulphated glycosaminoglycans (predominantly dermatan sulphate) and an increase in DNA (cellular) content. However, there were no significant differences between degenerate tendons that were 'calcified' and those degenerate specimens that contained normal concentrations of calcium. CONCLUSIONS: Although there was a relatively high prevalence of calcium salts in degenerate tendons, which might contribute to the pathological process (such as increased matrix collagen degradation), these data are consistent with the hypothesis that 'dystrophic calcification' of degenerate tendon matrix is a pathological entity distinct from cell mediated 'calcifying tendinitis'. Calcification is probably one possible outcome (or end point) of chronic tendon injury, although the possibility exists that in many cases, the presence of calcium salts may contribute to the tendon matrix degeneration.

Tendon degeneration and chronic shoulder pain: changes in the collagen composition of the human rotator cuff tendons in rotator cuff tendinitis.

OBJECTIVES: To analyse the collagen composition of normal adult human supraspinatus tendon and to compare with: (1) a flexor tendon (the common biceps tendon) which is rarely involved in any degenerative pathology; (2) degenerate tendons from patients with chronic rotator cuff tendinitis. METHODS: Total collagen content, collagen solubility and collagen type were investigated by hydroxyproline analysis, acetic acid and pepsin digestion, cyanogen bromide peptide analysis, SDS-PAGE and Western blotting. RESULTS: The collagen content of the normal cadaver supraspinatus tendons (n = 60) was 96.3 micrograms HYPRO/mg dry weight (range 79.3-113.3) and there was no significant change across the age range 11 to 95 years. There was no significant difference from the common biceps tendon [93.3 (13.5) micrograms HYPRO/mg dry weight, n = 24]. Although extremely insoluble in both acetic acid and pepsin, much of the collagen was soluble after cyanogen bromide digestion [mean 47.9% (29.8)]. Seventeen per cent (10/60) of the 'normal' cadaver supraspinatus tendon sample contained more than 5% type III collagen, although none of the common biceps tendons had significant amounts. Degenerate supraspinatus and subscapularis tendons had a reduced collagen content [83.8 (13.9) micrograms/mg dry weight and 76.9 (16.8) micrograms/mg dry wt respectively) and were more soluble in acetic acid, pepsin and cyanogen bromide (p < 0.001). Eighty two per cent (14/17) of supraspinatus tendons and 100% (8/8) of subscapularis tendons from patients with tendinitis contained more than 5% type III collagen. CONCLUSIONS: The changes in collagen composition in rotator cuff tendinitis are consistent with new matrix synthesis, tissue remodelling and wound healing, in an attempt to repair the tendon defect, even in old and degenerate tendons. An increase in type III collagen in some 'normal' cadaver supraspinatus tendons is evidence that changes in collagen synthesis and turnover may precede tendon rupture. These changes may be the result of repeated minor injury and microscopic fibre damage or a consequence of local factors such as reduced vascular perfusion, tissue hypoxia, altered mechanical forces and the influence of cytokines. These collagenous changes may accumulate with age and substantially weaken the tendon structure, predisposing the tendon to rotator cuff tendinitis and eventual tendon rupture.

Glycosaminoglycans of human rotator cuff tendons: changes with age and in chronic rotator cuff tendinitis.

OBJECTIVES: To analyse the glycosaminoglycans of the adult human rotator cuff tendon matrix, to characterise changes in the glycosaminoglycan composition with age and in chronic rotator cuff tendinitis. METHODS: Rotator cuff (supraspinatus) tendons (n = 84) and common biceps tendons (n = 26) were obtained from cadavers with no history of tendon pathology (age range 11-95 years). Biopsies of rotator cuff tendons (supraspinatus and subscapularis tendons, n = 53) were obtained during open shoulder surgery to repair shoulder lesions (age range 38-80 years). Glycosaminoglycans were extracted by papain digestion and analysed by cellulose acetate electrophoresis, the carbazole assay for uronic acid and the dimethylmethylene blue dye-binding assay for sulphated glycosaminoglycans. Some digests were analysed for keratan sulphate by 5D4 monoclonal antibody ELISA. Soluble proteoglycans were extracted in 4M guanidine hydrochloride and analysed by 4-15% SDS PAGE. RESULTS: The mean (SD) sulphated glycosaminoglycan (GAG) content of the normal cadaver supraspinatus tendon was 12.3 (4.3) micrograms/mg dry weight, between three and ten times greater than in the common biceps tendon [1.2 (0.6) micrograms/mg dry weight]. The major GAG was chondroitin sulphate [6.9 (2.6) micrograms/mg dry weight], with a smaller proportion of dermatan sulphate [2.5 (1.2) micrograms/mg dry weight]. In contrast, the common biceps tendon contained predominantly dermatan sulphate [0.8 (0.2) microgram/mg dry weight] with less chondroitin sulphate [0.2 (0.2) microgram/mg dry weight]. There was no difference in the concentration of hyaluronan in these tendons [9.3 (2.8) micrograms/mg dry weight and 10.8 (4.3) micrograms/mg dry weight respectively] and there was no significant change of hyaluronan with age. Keratan sulphate was a small but significant component of the supraspinatus tendon [0.43 (0.33) microgram/mg dry weight, n = 25], whereas there was little or none in the common biceps tendon [0.04 (0.05) microgram/mg dry weight, n = 8] and there was no significant change across the age range. In the supraspinatus tendon, there was a significant decrease in total glycosaminoglycan, chondroitin sulphate and dermatan sulphate with age (p < 0.001), whether expressed relative to the tendon dry weight or total collagen content, and no change in the relative proportion of the different GAG types. There was, however, a large degree of variation within the samples. Supraspinatus tendons from patients with chronic tendinitis had a significantly increased concentration of hyaluronan [30.4 (10.1) micrograms/mg dry weight, p < 0.001], chondroitin sulphate [8.4 (1.8) micrograms/mg dry weight, p < 0.05] and dermatan sulphate [3.8 (1.1) micrograms/mg dry weight, p < 0.001] compared with normal cadaver supraspinatus tendons, although the keratan sulphate content was not significantly different [0.18 (0.05) microgram/mg dry weight]. CONCLUSIONS: The normal supraspinatus tendon has the proteoglycan/glycosaminoglycan of tendon fibrocartilage, which it is suggested is an adaptation to mechanical forces (tension, compression and shear) which act on the rotator cuff tendons in the shoulder, although other factors such as reduced vascularity, low oxygen tension and the influence of local growth factors may also be important. This functional adaptation may have important consequences for the structural strength of the supraspinatus tendon and to influence the ability of the tendon to repair after injury. The glycosaminoglycan composition of tendon specimens from patients with chronic tendinitis is consistent with acute inflammation and new matrix proteoglycan synthesis, even in relatively old tendon specimens and after at least one injection of corticosteroid.

Results of the Souter-Strathclyde total elbow arthroplasty in patients with rheumatoid arthritis. A preliminary report.

The results of 19 consecutive Souter-Strathclyde total elbow arthroplasties (Zimmer, London) in 17 patients with a mean follow-up time of 41 months are reported. Pain relief was achieved in all cases, with 13 elbows becoming entirely pain-free. The mean range of flexion increased 24 degrees and extension improved 8 degrees, with upper limb function greatly improved. The complication rate was 32%, including three nerve palsies, of which two resolved completely, and three early postoperative dislocations. There were two cases of prosthetic loosening, one following revision surgery for a traumatic humeral fracture in the early postoperative period. The authors consider the overall functional results with the Souter-Strathclyde prosthesis to be satisfactory in this group of patients.

Case report: Ewing's sarcoma in distal tibial metaphysis mimicking osteomyelitis.

An 11-year-old girl presented with the clinical picture of osteomyelitis of the distal tibia. A bone scintigram, although abnormal, did not confirm the diagnosis, but a 99mTc leucocyte scan showed focal white cell uptake in the distal tibia. This was felt to confirm infection and subsequent aspiration revealed what was thought to be pus. However, histology of the aspirated material demonstrated Ewing's Sarcoma. The differential diagnosis and the place of scintigraphy in this clinical situation are discussed.

Subluxation of the posterior stabilized total knee arthroplasty. A report of two cases.

There has been only one previous report of dislocation of a posteriorly stabilized total knee arthroplasty. The authors present two further cases of subluxation of this prosthesis and report a method of accomplishing reduction that could not otherwise be achieved by conventional techniques. The current design of this prosthesis enabled revision of the polyethylene tibial component to be undertaken without removal of the cemented metal-backing tray, an advantage not previously appreciated.

Extension-supination sign in prearthroscopic elbow distension.

A clinical sign of extension and supination of the elbow is described after prearthroscopic distension with fluid. When elicited, intra-articular fluid placement is indicated, assisting correct location of the arthroscope within the joint.

[Assessment of shoulder function]. / Schulterfunktionsbeurteilung.

In 1980, a major study began on the recovery of shoulder function following injuries of various kinds. In order to try and assess shoulder function and it's recovery following injury, it became apparent that diagnostic assessments of the shoulder were of little value, and the Author worked on designing a method of shoulder functional assessment what would allow easy and repeated assessment of shoulder function at various intervals following injury. This method of shoulder functional assessment is now used as a standard practice in many centres, throughout the world, and this paper aims to present the clinical method of functional assessment, as used by the Author, in plotting progress following injury over a number of years. The method has been extensively used by the author and others over the past ten years, in studying the recovery of shoulder function in different disease processes, after injuries and after various treatments, including surgery.

Injuries to the elbow.

Presented is an outline of the anatomy, biomechanics and function of the elbow joint, as it relates to normal and sporting activities. A variety of elbow injuries, including fractures of the olecranon, radial head and distal humerus are presented with appropriate methods of treatment. The aim to return patients to early functional activity is stressed. Soft tissue and more chronic over-use problems are briefly discussed, and a treatment regimen presented. In general, elbow injuries which involve acute fractures, dislocations and ligament injuries should be treated aggressively, in order to achieve early functional mobility. The more chronic over-use elbow problems should be viewed with a certain caution, and results are not as predictable following treatment of such injuries and over-use problems.