Hand grip--a simple test for morbidity after fracture of the neck of femur

Mitochondrial function, grip strength, and activity are related to recovery of mobility after a total knee arthroplasty

Low muscle quality and a sedentary lifestyle are indicators for a slow recovery after a total knee arthroplasty (TKA). Mitochondrial function is an important part of muscle quality and a key driver of sarcopenia. However, it is not known whether it relates to recovery. In this pilot study, we monitored activity after TKA using a wrist mounted activity tracker and assessed the relation of mitochondrial function on the rate of recovery after TKA. Additionally, we compared the increase in activity as a way to measure recovery to traditional outcome measures. Patients were studied 2 weeks before TKA and up to 6 months after. Activity was monitored continuously. Baseline mitochondrial function (citrate synthase and complex [CP] 1-5 abundance of the electron transport chain) was determined on muscle tissue taken during TKA. Traditional outcome measures (Knee Injury and Osteoarthritis Outcome Score [KOOS], timed up-and-go [TUG] completion time, grip, and quadriceps strength) were performed 2 weeks before, 6 weeks after, and 6 months after TKA. Using a multivariate regression model with various clinical baseline parameters, the following were significantly related to recovery: CP5 abundance, grip strength, and activity (regression weights 0.13, 0.02, and 2.89, respectively). During recovery, activity correlated to the KOOS-activities of daily living (ADL) score (r = 0.55, p = 0.009) and TUG completion time (r = -0.61, p = 0.001). Mitochondrial function seems to be related to recovery, but so are activity and grip strength, all indicators of sarcopenia. Using activity trackers before and after TKA might give the surgeon valuable information on the expected recovery and the opportunity to intervene if recovery is low.

Conditionally Essential Amino Acid Supplementation Reduces Postoperative Complications and Muscle Wasting After Fracture Fixation: A Randomized Controlled Trial

BACKGROUND

Postoperative complications and substantial loss of physical function are common after musculoskeletal trauma. We conducted a prospective randomized controlled trial to assess the impact of conditionally essential amino acid (CEAA) supplementation on complications and skeletal muscle mass in adults after operative fixation of acute fractures.

METHODS

Adults who sustained pelvic and extremity fractures that were indicated for operative fixation at a level-I trauma center were enrolled. The subjects were stratified based on injury characteristics (open fractures and/or polytrauma, fragility fractures, isolated injuries) and randomized to standard nutrition (control group) or oral CEAA supplementation twice daily for 2 weeks. Body composition (fat-free mass [FFM]) was measured at baseline and at 6 and 12 weeks postoperatively. Complications were prospectively collected. An intention-to-treat analysis was performed. The relative risk (RR) of complications for the control group relative to the CEAA group was determined, and linear mixed-effects models were used to model the relationship between CEAA supplementation and changes in FFM.

RESULTS

Four hundred subjects (control group: 200; CEAA group: 200) were enrolled. The CEAA group had significantly lower overall complications than the control group (30.5% vs. 43.8%; adjusted RR = 0.71; 95% confidence interval [CI] = 0.55 to 0.92; p = 0.008). The FFM decreased significantly at 6 weeks in the control subjects (-0.9 kg, p = 0.0205), whereas the FFM was maintained at 6 weeks in the CEAA subjects (-0.33 kg, p = 0.3606). This difference in FFM was not seen at subsequent time points.

CONCLUSIONS

Our results indicate that CEAA supplementation has a protective effect against common complications and early skeletal muscle wasting after operative fixation of extremity and pelvic fractures. Given the potential benefits of this inexpensive, low-risk intervention, multicenter prospective studies in focused trauma populations are warranted.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Role of handgrip strength testing in pre-anaesthetic check-up: A prospective cross-sectional study

Background and Aims

Frailty has been known to be associated with postoperative adverse events and longer hospital length of stay (LOS). Hand grip strength (HGS) is one of the parameters of measuring frailty. The aim of the study was to correlate preoperative handgrip strength and 30-day outcome of patients undergoing major abdominal surgery. It also aimed to evaluate the role of the standard preoperative variables like metabolic equivalents, revised cardiac risk index (RCRI), serum albumin, and serum creatinine along with their association with HGS testing in determining the postoperative outcome in surgical patients.

Material and Methods

This prospective observational study included 149 American Society of Anesthesiologists class III/IV patients presenting for major abdominal surgery. A mean of three measurements of dominant HGS using Camry hand dynamometer was measured. The patients were divided into groups: weak, normal, and strong depending on grip strength. Patients were followed for 30 days and postoperative outcome in terms of ventilatory support, admission to intensive care unit, cardiac complications, in-hospital mortality, and LOS were recorded. Observational data obtained were reported as mean value and analyzed using Student's t-test or Wilcoxon/Mann-Whitney Rank test. Associations between RCRI, serum albumin, and LOS with HGS were evaluated using logistic regression.

Results

The hospital LOS was significantly longer in patients with weak HGS (15.11 ± 11.03 days versus 10 ± 5.71 days, P = 0.001). Patients with weak HGS had significantly lower mean serum albumin levels compared to normal HGS (P = 0.0001) and a statistically significant RCRI score (P = 0.013).

Conclusion

HGS can be used as a preoperative test in predicting hospital LOS after major surgery.

Why Do Falls and Lower Limb Fractures Occur More Frequently in the Diabetic Patient and How Can They Be Prevented?

Due to primarily sarcopenia and hypoglycemia but also neuropathy, hypotension, analgesics and polypharmacy, there is an increased incidence of falls and hip fractures in both the type 1 and type 2 diabetic patient. Utilization of insulin, hypotensive drugs, analgesics and perhaps canagliflozin further increases the risk. Thiazolidinedione use may increase the risk of osteoporosis and fracture. Prolonged hyperglycemia resulting in cross-linking of collagen and advanced glycosylation end products alter the microarchitecture and increase bone fragility. Higher serum vitamin D levels seem to decrease the incidence of both falls and fractures. Following a hip fracture, mortality in the diabetic patient is increased largely because of cardiovascular events and pneumonia. Prevention of sarcopenia includes dietary therapy, vitamin D and testosterone replacement when appropriate.

Handgrip strength predicts 1-year functional recovery and mortality in hip fracture patients

OBJECTIVES

Muscle strength is a possible predictor of adverse events. It could have prognostic value in patients with hip fracture (HF). The aim of this study was to determine if handgrip strength is associated with functional impairment, readmissions, and mortality at one year in elderly patients with HF.

DESIGN

A prospective observational study was carried out. It included a cohort of patients aged 65 years or older with a diagnosis of fragility HF, consecutively from January 2013 to February 2014 and seen in follow-up at one year. Statistical analysis was performed using SPSS v21 software.

MAIN OUTCOME MEASURES

Five hundred and nine patients with a mean age of 85.4 ± 0.3 years were included, of whom 403 (79.2 %) were women. Clinical and functional outcomes, laboratory parameters and anthropometric measurements were collected.

RESULTS

Of the total sample, 339 (66.6 %) had reduced handgrip strength, and these patients were older, more frequently institutionalized, had poorer functional and cognitive status, higher comorbidity, higher surgical risk, lower body mass index and a greater intra-hospital mortality (all p < 0.01). At one year, patients with lower handgrip strength had a major change in their ability to walk (32.7 % vs. 10.9 %, p < 0.001) and a higher mortality rate (30.4 % vs. 8.8 %, p < 0.001). However, in patients over 91 years of age, there was no association between lower handgrip strength and change in ability to walk. There were no differences in the number of readmissions.

CONCLUSION

Low handgrip strength in elderly patients with HF predicts greater functional disability and higher long-term mortality.

Do Nationally Representative Cutpoints for Clinical Muscle Weakness Predict Mortality? Results From 9 Years of Follow-up in the Health and Retirement Study

BACKGROUND

Muscle weakness, as measured by handgrip strength, is associated with cardiovascular and all-cause mortality; however, there are wide inconsistencies in the magnitude of these effects due to divergent definitions used to define muscle weakness across studies. Therefore, the objective of this study was to examine the relationship between previously defined sex- and race-specific cutpoints of clinical muscle weakness and early mortality.

METHODS

Data come from the 2006-2014 Health and Retirement Study. Time-varying clinical muscle weakness, as defined by handgrip strength cutpoints, was the primary exposure. Time to death, ascertained from the National Death Index, was the outcome of interest. The association between time-varying clinical muscle weakness and early mortality across a 9-year observation period was determined using Kaplan-Meier methods and extended Cox regression.

RESULTS

Out of the 8,326 individuals in the study, 1,799 deaths (21%) occurred during the observation period. Median follow-up time was 8.3 years (SD ±1.9 years). Weak individuals had a steeper decline in their survival trajectory, compared to non-weak individuals (Log-Rank test, p < .001). After adjusting for sociodemographic factors and time-varying smoking history, weak individuals were over 50% more likely to die earlier than non-weak individuals (hazard ratio [HR] = 1.52, 95% confidence interval [CI] = 1.15, 1.47).

CONCLUSIONS

This is the first study to use muscle weakness cutpoints derived in a nationally representative sample to identify those individuals who may be at greatest risk for premature mortality. Results underscore the importance of muscle weakness, as defined by handgrip strength, as a key risk factor for premature mortality in older Americans.

POSSIBLE ROLE OF NUTRITION IN PREVENTION OF SARCOPENIA AND FALLS

Objective: In this review, we analyze the foundation of sarcopenia as a potentially modifiable risk factor for falls, and we try to formulate practical strategies for nutritional interventions aimed at reducing the risk for sarcopenia and falls in our elderly patients. Methods: An extensive literature search was performed using the PubMed and the Google Scholar databases. Results: Falls are a common and costly source of injury and death in elderly adults. A large proportion of injurious falls are due to a trip or slip, suggesting that muscular factors are major determinants of both fall risk and the risk for fall-related injury. Conclusion: An increasing body of evidence links sarcopenia, the loss of muscle strength and mass that occurs with advancing age, with an increased risk for falls. Nutritional factors, as well as exercise, can help with both prevention and treatment of sarcopenia and may reduce the risk of falls in the elderly. Abbreviations: 25-OHD = 25-hydroxyvitamin D; EAA = essential amino acid; IGF-1 = insulin-like growth factor 1; IU = international units; MPS = muscle protein synthesis; PUFA = polyunsaturated fatty acid.

Sarcopenia

Sarcopenia is a progressive and generalised skeletal muscle disorder involving the accelerated loss of muscle mass and function that is associated with increased adverse outcomes including falls, functional decline, frailty, and mortality. It occurs commonly as an age-related process in older people, influenced not only by contemporaneous risk factors, but also by genetic and lifestyle factors operating across the life course. It can also occur in mid-life in association with a range of conditions. Sarcopenia has become the focus of intense research aiming to translate current knowledge about its pathophysiology into improved diagnosis and treatment, with particular interest in the development of biomarkers, nutritional interventions, and drugs to augment the beneficial effects of resistance exercise. Designing effective preventive strategies that people can apply during their lifetime is of primary concern. Diagnosis, treatment, and prevention of sarcopenia is likely to become part of routine clinical practice.

CORP: Measurement of upper and lower limb muscle strength and voluntary activation

Muscle strength, the maximal force-generating capacity of a muscle or group of muscles, is regularly assessed in physiological experiments and clinical trials. An understanding of the expected variation in strength and the factors that contribute to this variation is important when designing experiments, describing methodologies, interpreting results, and attempting to replicate methods of others and reproduce their findings. In this review (Cores of Reproducibility in Physiology), we report on the intra- and inter-rater reliability of tests of upper and lower limb muscle strength and voluntary activation in humans. Isometric, isokinetic, and isoinertial strength exhibit good intra-rater reliability in most samples (correlation coefficients ≥0.90). However, some tests of isoinertial strength exhibit systematic bias that is not resolved by familiarization. With the exception of grip strength, few attempts have been made to examine inter-rater reliability of tests of muscle strength. The acute factors most likely to affect muscle strength and serve as a source of its variation from trial-to-trial or day-to-day include attentional focus, breathing technique, remote muscle contractions, rest periods, temperature (core, muscle), time of day, visual feedback, body and limb posture, body stabilization, acute caffeine consumption, dehydration, pain, fatigue from preceding exercise, and static stretching >60 s. Voluntary activation, the nervous system’s ability to drive a muscle to create its maximal force, exhibits good intra-rater reliability when examined with twitch interpolation (correlation coefficients >0.80). However, inter-rater reliability has not been formally examined. The methodological factors most likely to influence voluntary activation are myograph compliance and sensitivity; stimulation location, intensity, and inadvertent stimulation of antagonists; joint angle (muscle length); and the resting twitch.

GRIP Strength Norms for Elderly Women

As part of community health screenings, the grip strength of 113 independently ambulatory women ( M age = 75.2 ± 7.3 yr.) was measured. Norms derived from the measurements are presented and compared with (a) norms reported for similar procedures about 20 years ago and (b) values for disabled women.

Identification of dynapenia in older adults through the use of grip strength t-scores

INTRODUCTION

The aim of this study was to generate reference values and t-scores (1.0-2.5 standard deviations below average) for grip strength for healthy young adults and to examine the utility of t-scores from this group for the identification of dynapenia in older adults.

METHODS

Our investigation was a population-based, general community secondary analysis of cross-sectional grip strength data utilizing the NIH Toolbox Assessment norming sample. Participants consisted of community-dwelling adults, with age ranges of 20-40 years (n = 558) and 60-85 years (n = 390). The main outcome measure was grip strength using a Jamar plus dynamometer.

RESULTS

Maximum grip strengths were consistent over the 20-40-year age group [men 108.0 (SD 22.6) pounds, women 65.8 (SD 14.6) pounds]. Comparison of older group grip strengths to those of the younger reference group revealed (depending on age strata) that 46.2-87.1% of older men and 50.0-82.4% of older women could be designated as dynapenic on the basis of t-scores.

CONCLUSIONS

The use of reference value t-scores from younger adults is a promising method for determining dynapenia in older adults.

Preoperative grip strength measurement and duration of hospital stay in patients undergoing total hip and knee arthroplasty

PURPOSE

This study explored whether a relationship exists between preoperative pinch and power grip strength, and length of hospital stay in patients undergoing hip and knee arthroplasty at a busy UK hospital. We investigated whether handgrip dynamometry could be used preoperatively to identify patients at greater risk of longer inpatient stays. This would allow focussed intervention preoperatively and facilitate predictors of length of stay postoperatively.

METHODS

One hundred and sixty-four patients (64 male, 100 female) undergoing lower limb arthroplasty (83 total knee replacement, 81 total hip replacement) were assessed in pre-admission clinic. Average measurements of pinch grip, power grip and grip endurance were taken from each patient using the Jamar hydraulic dynamometer (Jamar, USA). Duration of inpatient stay of each patient was recorded.

RESULTS

Average duration of hospital stay was 9.4 days. Both average pinch grip strength and average power grip strength had a significant negative correlation with duration of inpatient stay. Those patients with a pinch grip strength less than 6.3 kg remained an inpatient for an average of 2 days longer than those with a pinch grip greater than 6.3 kg.

CONCLUSIONS

This simple test may be highly beneficial preoperatively in identifying those patients likely to require longer inpatient stays and therefore those who would benefit from early nutritional intervention and focussed physiotherapy. It may also facilitate predictors of length of stay postoperatively. We believe this may effect significant cost reductions in the NHS.

A systematic review of dynamometry and its role in hand trauma assessment

The dynamometer was developed by American neurologists and came into general use in the late 19th century. It is still used in various ways as a diagnostic and prognostic tool in clinical settings. In this systematic review we assessed in detail the different uses of dynamometry, its reliability, different dynamometers used and the influence of rater experience by bringing together and evaluating all published literature in this field. It was found that dynamometry is applied in a wide range of medical conditions. Furthermore, the great majority of studies reported acceptable to high reliability of dynamometry. Jamar mechanical dynamometer was used most often in the studies reviewed. There were mixed results concerning the effect of rater experience. The factors influencing the results of dynamometry were identified as age, gender, body weight, grip strength, BMI, non/dominant hand, assessing upper/lower limbs, rater and patient’s strength and the distance from the joint where the dynamometer is placed. This review provides an understanding of the relevance and significance of dynamometry which should serve as a starting point to guide its use in hand trauma assessment. On the basis of our findings, we suggest that hand dynamometry has a great potential, and could be used more often in clinical practice.

Preoperative muscle weakness as defined by handgrip strength and postoperative outcomes: a systematic review

BACKGROUND

Reduced muscle strength- commonly characterized by decreased handgrip strength compared to population norms- is associated with numerous untoward outcomes. Preoperative handgrip strength is a potentially attractive real-time, non-invasive, cheap and easy-to-perform "bedside" assessment tool. Using systematic review procedure, we investigated whether preoperative handgrip strength was associated with postoperative outcomes in adults undergoing surgery.

METHODS

PRISMA and MOOSE consensus guidelines for reporting systematic reviews were followed. MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Clinical Trials (1980-2010) were systematically searched by two independent reviewers. The selection criteria were limited to include studies of preoperative handgrip strength in human adults undergoing non-emergency, cardiac and non-cardiac surgery. Study procedural quality was analysed using the Newcastle-Ottawa Quality Assessment score. The outcomes assessed were postoperative morbidity, mortality and hospital stay.

RESULTS

Nineteen clinical studies (17 prospective; 4 in urgent surgery) comprising 2194 patients were identified between1980-2010. Impaired handgrip strength and postoperative morbidity were defined inconsistently between studies. Only 2 studies explicitly ensured investigators collecting postoperative outcomes data were blinded to preoperative handgrip strength test results. The heterogeneity of study design used and the diversity of surgical procedures precluded formal meta-analysis. Despite the moderate quality of these observational studies, lower handgrip strength was associated with increased morbidity (n = 10 studies), mortality (n = 2/5 studies) and length of hospital stay (n = 3/7 studies).

CONCLUSIONS

Impaired preoperative handgrip strength may be associated with poorer postoperative outcomes, but further work exploring its predictive power is warranted using prospectively acquired, objectively defined measures of postoperative morbidity.

Hand-grip strength is a simple and effective outcome predictor in esophageal cancer following esophagectomy with reconstruction: a prospective study

Background

Surgery for esophageal cancer usually carries considerable complication and mortality rate. Adequate preoperative evaluation is mandatory to decrease complication rate. Hand-grip strength is a useful measure to assess the extent of aging, nutrition and patient's overall condition. Because preoperative nutrition state and physiologic aging process play important roles in postoperative recovery, we would like to know if hand-grip strength is an adequate tool for such evaluation.

Material and methods

From January 1st, 2007 to December 31, 2008, there was 68 cases underwent esophagectomy with reconstruction due to esophageal cancer in our hospital. After excluding 7 patients of incomplete data and loss of follow-up, there were 61 patients included in the study.

Results

There were 54 men and 7 women. The mean age is 60.7. Most of patients had squamous cell carcinoma. Patient with weak hand-grip strength prior to operation had exceedingly high rates of complication and mortality within 6 months after operation. Compared to other risk factors, low grip strength has highest relative risks for both mortality and morbidity.

Conclusion

Because test for hand-grip strength is cheap, not time-consuming and has high predictive value, it may be included in routine preoperative evaluation.

A study of grip endurance and strengh in different elbow positions

Background

The aim of our study was twofold. The first was to investigate the optimum position of the elbow while measuring grip endurance. The second was to investigate the optimum position of the elbow while measuring peak grip strength. The American Society of Hand Therapists advocate estimation of grip strength with the elbow flexed at 90° with the subject in the sitting position . As far as we are aware, there have been no reports in English literature regarding studies done to evaluate the position of the elbow while measuring grip endurance.

Materials and methods

A total of 45 healthy adults (16 males, 29 females) participated in this study. A computerised handgrip analyser was used to measure the peak strength in the non-dominant hand, followed by measurement of the grip endurance. These measurements were conducted in 90° of flexion and full extension of the elbow for each participant.

Results

Mean endurance in flexion was 71.0 N (SD 22.9) and in extension was 68.7 N (SD 27.4). Mean peak grip strength in flexion was 262.8 N (SD 73.1) and in extension was 264.1 N (SD 82.0). T test analysis showed no statistical significance for elbow positions for grip endurance (P = 0.67) and peak gip strength (P = 0.93).

Conclusion

Practical implications from this study are that grip endurance training can be undertaken with the elbow in 90° of flexion or full extension.

Dynamometer measurements of hand-grip strength predict multiple outcomes

Hand-grip strength, which can be measured easily and objectively using a dynamometer, is predictive of multiple outcomes among a variety of subjects. Although the literature is not fully consistent, it tends to support grip strength as a predictor of postoperative complications, mortality, and functional decline. Hand-grip dynamometry may merit broader application as a screening procedure.

Assessing the efficacy of nutritional support

This review outlines the conventional methods of assessing nutritional status and their limitations in the presence of acute trauma and sepsis. It also discusses the problems of attempting to improve or at least maintain nutritional status in the presence of an inflammatory stimulus. Most of the conventional markers of nutritional status are altered in trauma and sepsis with decreases in plasma protein concentrations and muscle strength, an apparent depression of immune function and an increase in extracellular fluid volume. It also appears to be impossible to improve nutritional status in the presence of a severe inflammatory stimulus, and the most one can hope for is to attenuate the rate of decline. The evidence for these observations is discussed.

Immediate postoperative enteral feeding results in impaired respiratory mechanics and decreased mobility

OBJECTIVE

The authors set out to determine whether immediate enteral feeding minimizes early postoperative decreases in handgrip and respiratory muscle strength.

SUMMARY BACKGROUND DATA

Muscle strength decreases considerably after major surgical procedures. Enteral feeding has been shown to restore strength rapidly in other clinical settings.

METHODS

A randomized, controlled, nonblinded clinical trial was conducted in patients undergoing esophagectomy or pancreatoduodenectomy who received immediate postoperative enteral feeding via jejunostomy (fed, n = 13), or no enteral feeding during the first 6 postoperative days (unfed, n = 15). Handgrip strength, vital capacity, forced expiratory volume in one second (FEV1), and maximal inspiratory pressure (MIP) were measured before surgery and on postoperative days 2, 4, and 6. Fatigue and vigor were evaluated before surgery and on postoperative day 6. Mobility was assessed daily after surgery using a standardized descriptive scale. Postoperative urine biochemistry was evaluated in daily 24-hour collections.

RESULTS

Postoperative vital capacity (p < 0.05) and FEV1 (p = 0.07) were consistently lower (18%-29%) in the fed group than in the unfed group, whereas grip strength and maximal inspiratory pressure were not significantly different. Postoperative mobility also was lower in the fed patients (p < 0.05) and tended to recover less rapidly (p = 0.07). Fatigue increased and vigor decreased after surgery (both p < or = 0.001), but changes were similar in the fed and unfed groups. Intensive care unit and postoperative hospital stay did not differ between groups.

CONCLUSIONS

Immediate postoperative jejunal feeding was associated with impaired respiratory mechanics and postoperative mobility and did not influence the loss of muscle strength or the increase in fatigue, which occurred after major surgery. Immediate postoperative enteral feeding should not be routine in well-nourished patients at low risk of nutrition-related complications.

Impaired recovery of strength in older patients after major abdominal surgery

OBJECTIVE

This study compared changes in muscle strength after major elective abdominal surgery in young and old patients, and related these changes to body composition and nitrogen balance.

SUMMARY BACKGROUND DATA

The breakdown of muscle protein, erosion of lean tissue, and negative nitrogen balance are characteristic metabolic responses to surgical illness. With a substantial loss of muscle mass typical of advancing age, the authors postulated that older patients would be weaker during acute surgical illness and less able to maintain muscle function and meet metabolic demands.

METHODS

Active, community-dwelling individuals undergoing major abdominal procedures who were 70 years of age or older or 50 years of age or younger were studied. Total body water (TBW) was determined preoperatively by deuterium oxide dilution. Maximal voluntary handgrip, respiratory muscle strength, and visual analog pain scores were measured preoperatively and on postoperative days 2, 4, and 6. All urine was collected postoperatively for 7 days for determination of total nitrogen, creatinine, and cortisol.

RESULTS

The young (age, 36 +/- 9 years [mean +/- standard deviation]; n = 20) and old groups (age, 77 +/- 5 years; n = 20) were similar regarding weight, sex distribution, nutritional status, surgical procedures and anesthesia, and postoperative urine cortisol values. Age group, time after operation, and interaction effects were significant for each strength variable (all p < 0.005 by analysis of variance). Older patients had lower preoperative strength (29% to 41%) and mean 24-hour urine creatinine (27%). Postoperative strength was decreased most markedly on postoperative day 2, with similar proportional changes in the two age groups but lower absolute levels in the older patients. The rate of recovery of strength was substantially less rapid and complete in older patients. Older patients had less postoperative pain and received much less parenteral narcotic than younger patients. Postoperative urine nitrogen was similar in each group. Recovery of strength was not related to malignancy, preoperative strength, muscle mass (urine creatinine), lean body mass (TBW), sex, malignancy, pain, or narcotic administration.

CONCLUSIONS

Older patients are weaker preoperatively than younger patients; their strength falls to lower levels after surgery and their postoperative recovery of strength is impaired. The lesser preoperative strength of older patients is due in large part but not totally to diminished muscle mass. Their impaired postoperative recovery appears to be related to more acute factors, such as muscle energetics or substrate availability.

Grip strength: a measure of the proportion of protein loss in surgical patients

Measurements of voluntary hand grip strength (GS) are a sensitive predictor of postoperative complications. The loss of body protein is thought to be important in the development of these postoperative complications, but the relationship between GS and body protein status has not been studied. We have measured GS (by hand dynamometry), total body protein (indirectly by mid-arm muscle circumference, and directly by in vivo neutron activation analysis) and the proportion of protein loss (protein index) in 80 patients with gastrointestinal disease and 87 normal volunteers. Using regression analysis, a matched study and clinical decision analysis, it has been demonstrated that GS is a sensitive measurement of the degree of protein loss. The results support more widespread use of GS measurements in the identification of patients at high risk of postoperative complications and in the monitoring of patient response to nutritional intervention.