J. E. McEachan

Grip Strength and Forearm Circumference in a Healthy Population

Two hundred and fifty subjects were recruited. Age, sex, hand preference and anthropometric measurements were recorded for each subject. Grip strength was measured using a Jamar hydraulic dynamometer. Multiple regression analyses were performed. One hundred and seventy two subjects were men and 78 were women. Twenty-six subjects were left hand dominant. Hand grip strength was greatest for the 35 to 44 year old group for both sexes. Grip strength was consistently greater for men than women. Contralateral grip strength predicted maximum grip strength for both sexes. Forearm circumference predicted maximum hand grip strength for men. Although there was a large range of forearm circumferences in the population, there was little difference between sides for each subject (100% less than 2 cm). The demonstrated relationships between: (i) contralateral grip strengths and (ii) grip strength and forearm circumference lead us to suggest that for certain pathologies, a difference in forearm circumference greater than 2 cm may lend credence to a measurement of diminished grip strength.

Total elbow replacement: outcome of 1,146 arthroplasties from the Scottish Arthroplasty Project.

Background and purpose Total elbow replacement (TER) is used in the treatment of inflammatory arthropathy, osteoarthritis, and posttraumatic arthrosis, or as the primary management for distal humeral fractures. We determined the annual incidence of TER over an 18-year period. We also examined the effect of surgeon volume on implant survivorship and the rate of systemic and joint-specific complications. Methodology We examined a national arthroplasty register and used linkage with national hospital episode statistics, and population and mortality data to determine the incidence of complications and implant survivorship. Results There were 1,146 primary TER procedures (incidence: 1.4 per 105 population per year). The peak incidence was seen in the eighth decade and TER was most often performed in females (F:M ratio = 2.9:1). The primary indications for surgery were inflammatory arthropathy (79%), osteoarthritis (9%), and trauma (12%). The incidence of TER fell over the period (r = –0.49; p = 0.037). This may be due to a fall in the number of procedures performed for inflammatory arthropathy (p < 0.001). The overall 10-year survivorship was 90%. Implant survival was better if the surgeon performed more than 10 cases per year. Interpretation The prevalence of TER has fallen over 18 years, and implant survival rates are better in surgeons who perform more than 10 cases per year. A strong argument can be made for a managed clinic network for total elbow arthroplasty.

Socioeconomic deprivation and the epidemiology of carpal tunnel syndrome

Deprivation has been recognized as a major determinant of health and is associated with several musculoskeletal conditions. This study examines the effect of deprivation on the incidence of carpal tunnel syndrome using a regional prospective audit database. Over a 6 year period there were 1564 patients diagnosed with CTS with an annual incidence of 72/100,000 population. There was a significant difference in population incidence of CTS from the most deprived (81/100,000) to the least deprived (62/100,000) (p = 0.003). Functional impairment was higher in the most deprived group compared with the least (DASH 56 vs 48, p = 0.001). The most deprived group exhibited the greatest exposure to occupation vibration (42.7%), and had the greatest risk of bilateral disease (OR = 2.33, p < 0.001). We report an association between socioeconomic deprivation and carpal tunnel syndrome, with the disease being more likely to be bilateral and have a poorer DASH score in the most deprived patients.

The outcome of carpal tunnel decompression in patients with diabetes mellitus

Diabetes mellitus is recognised as a risk factor for carpal tunnel syndrome. The response to treatment is unclear, and may be poorer than in non-diabetic patients. Previous randomised studies of interventions for carpal tunnel syndrome have specifically excluded diabetic patients. The aim of this study was to investigate the epidemiology of carpal tunnel syndrome in diabetic patients, and compare the outcome of carpal tunnel decompression with non-diabetic patients. The primary endpoint was improvement in the QuickDASH score. The prevalence of diabetes mellitus was 11.3% (176 of 1564). Diabetic patients were more likely to have severe neurophysiological findings at presentation. Patients with diabetes had poorer QuickDASH scores at one year post-operatively (p = 0.028), although the mean difference was lower than the minimal clinically important difference for this score. After controlling for underlying differences in age and gender, there was no difference between groups in the magnitude of improvement after decompression (p = 0.481). Patients with diabetes mellitus can therefore be expected to enjoy a similar improvement in function.

Carpal tunnel syndrome: the association with occupation at a population level

The aim of this study was to examine the association of occupation and gender with the incidence and severity of carpal tunnel syndrome (CTS). We examined 884 patients of working age, diagnosed with CTS, in a specialist hand clinic that was the only provider of hand services to a health board area. We categorized occupation using the Standard Occupational Classification 2010 (SOC2010) and used local census data to calculate the incidence in each of the nine major occupational groups. The greatest incidence was in caring and leisure occupations (197 per 100 000 population per year), while the lowest incidence was in the associate professional group (37 per 100 000). Professional occupations had a high incidence of CTS, along with skilled trades and elementary occupations. Women had a higher incidence of CTS than men in managerial, professional, skilled trades, and elementary occupations (OR 2.9–3.6). The Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score varied across occupational groups (p < 0.001) and was worst in the caring and leisure group. As traditional heavy industry associated with previously described occupational risks declines, new patterns of occupational association may emerge. We recommend ongoing observational research of potential occupational risk factors to identify these new trends.

Preventing venous thromboembolism in elective upper limb surgery

BACKGROUND Deep venous thrombosis (DVT) and pulmonary embolism (PE) have considerable clinical and economic consequences. The prevention of venous thrombosis and PE are increasingly seen as quality markers for surgery. Guidance is available from a number of sources to stratify risk for different patients and procedures and to define an appropriate standard of care. Despite this, best practice is unclear. METHODS We reviewed the available guidance for orthopedic surgeons undertaking elective upper limb surgery with respect to prescribing DVT prophylaxis. Material was identified from publications produced by professional and regulatory bodies, including United States Surgeon General, United Kingdom Department of Health, the American Academy of Orthopaedic Surgeons, the Scottish Intercollegiate Guideline Network, the National Institute for Clinical Excellence, and the American College of Chest Physicians, as well as a structured MEDLINE database search. RESULTS The picture is particularly confused in the case of elective upper limb surgery. Much of the evidence for prescribing DVT prophylaxis is related to lower limb surgery or trauma surgery. CONCLUSIONS Failing to prescribe prophylaxis against venous thromboembolism (VTE) may be presented as a failure of care. We present a review of current guidance and the supporting evidence in order to establish evidence-based best practice and a standard of care for elective upper limb surgery. LEVEL OF EVIDENCE Review Article.

Interpretation of the QuickDASH score after open carpal tunnel decompression: threshold values associated with patient satisfaction:

We studied the correlation between change in the QuickDASH score and the absolute post-operative QuickDASH score with patient satisfaction after open carpal tunnel decompression. Threshold values in the QuickDASH score, the point at which the sensitivity and specificity are maximal in predicting patient satisfaction, were identified. During the study period, outcome data were compiled for 937 carpal tunnel decompressions, which included 219 (23%) male and 718 (77%) female patients with a mean age of 58 years (standard deviation (SD) 14). There was a significant improvement (mean difference 32, 95% confidence interval (CI) 30 to 34) in the QuickDASH from a mean of 54 (SD 20) to 22 (SD 23) at 1 year after surgery. There were 808 (86%) patients who defined their outcome as satisfactory at 1 year. The identified threshold values for the post-operative QuickDASH score (⩽34 points) and the change (⩾20 points) in the score were highly predictive of patient satisfaction. However, these threshold values varied significantly according to the baseline pre-operative score. The threshold values identified in the QuickDASH can be used to interpret the score. However, the influence of the pre-operative baseline score should be taken into account when comparing different cohorts of patients or using the values to power future studies. Level of Evidence IV: Prognosis, observational cohort study

Pain and Carpal Tunnel Syndrome

PURPOSE Pain is not a classical symptom of carpal tunnel syndrome (CTS), with the exception of numbness that is so intense that it is described by patients as painful. The primary aim of our study was to determine which factors correlated with pain for patients diagnosed with CTS. METHODS We prospectively assessed all patients diagnosed with CTS in our unit over a 1-year period. We recorded demographic details for all patients, including past medical history, body mass index, smoking, and occupation. The diagnosis and severity of carpal tunnel syndrome were established through a combination of history, clinical assessment, and nerve conduction studies. Of 275 patients diagnosed and treated for CTS, 183 were women (67%), the mean age was 55 years (range, 22-87 y), and 166 cases were bilateral (60%). The mean body mass index was 29.5 kg/m2 (range, 17-48 kg/m2), and 81 patients smoked (30%). Patients completed a Short Form-McGill pain questionnaire (SF-MPQ) as a measure of pain at initial presentation. We assessed outcome 1 year after intervention using the Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score. RESULTS We found no association between pain according to the SF-MPQ and the positive clinical signs of CTS or positive nerve conduction studies. Multivariate analysis demonstrated that smoking and bilateral disease independently correlated with the overall SF-MPQ, with similar findings on subanalysis. Independent factors associated with an increased improvement in the QuickDASH at 1 year were the presentation QuickDASH score, positive nerve conduction studies, and smoking. CONCLUSIONS The only independent factors that correlated with pain at presentation of CTS were smoking and bilateral disease. Pain according to the SF-MPQ was not associated with classical clinical findings of the disease or with positive findings on nerve conduction testing. TYPE OF STUDY/LEVEL OF EVIDENCE Prognostic I.

Carpal tunnel decompression in the super-elderly: functional outcome and patient satisfaction are equal to those of their younger counterparts

There is conflicting evidence about the functional outcome and rate of satisfaction of super-elderly patients (≥ 80 years of age) after carpal tunnel decompression. We compiled outcome data for 756 patients who underwent a carpal tunnel decompression over an eight-year study period, 97 of whom were super-elderly, and 659 patients who formed a younger control group (< 80 years old). There was no significant difference between the super-elderly patients and the younger control group in terms of functional outcome according to the mean (0 to 100) QuickDASH score (adjusted mean difference at one year 1.8; 95% confidence interval (CI) -3.4 to 7.0) and satisfaction rate (odds ratio (OR) 0.78; 95% CI 0.34 to 1.58). Super-elderly patients were, however, more likely to have thenar muscle atrophy at presentation (OR 9.2, 95% CI 5.8 to 14.6). When nerve conduction studies were obtained, super-elderly patients were more likely to have a severe conduction deficit (OR 12.4, 95% CI 3.0 to 51.3). Super-elderly patients report functional outcome and satisfaction rates equal to those of their younger counterparts. They are more likely to have thenar muscle atrophy and a severe nerve conduction deficit at presentation, and may therefore warrant earlier decompression.

Tensioning of Prolene reduces creep under cyclical load: relevance to a simple pre-operative manoeuvre

A longitudinal stretch or ‘pre-tensioning’ is a method employed by some surgeons to improve the handling characteristics of a suture. We used a tensile tester to assess the effect of pre-tensioning on the mechanical properties of two suture materials (3-0 Prolene and 3-0 Ethibond) commonly used for flexor tendon repair. A cyclical loading programme was used to simulate an early rehabilitation regime. All sutures were subsequently tested to failure (for ultimate tensile strength). The pre-tensioned Prolene sutures showed significantly less creep after cyclical loading in comparison to controls. Conversely pre-tensioning had no measurable effect on the deformation of Ethibond by creep. There was no effect on ultimate tensile strength for either material. The propensity of Prolene to creep (and thereby form a ‘gap’ in tendon repairs) can be reduced by pre-tensioning.