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M A Kuskowski

Publications and source records attributed to M A Kuskowski.

At least 19 recordsLinked to original sources

A quantitative analysis of the sensory and sympathetic innervation of the mouse pancreas.

Pain from pancreatitis or pancreatic cancer can be both chronic and severe although little is known about the mechanisms that generate and maintain this pain. To define the peripheral sensory and sympathetic fibers involved in transmitting and modulating pancreatic pain, immunohistochemistry and confocal microscopy were used to examine the sensory and sympathetic innervation of the head, body and tail of the normal mouse pancreas. Myelinated sensory fibers were labeled with an antibody raised against 200 kD neurofilament H (clone RT97), thinly myelinated and unmyelinated peptidergic sensory fibers were labeled with antibodies raised against calcitonin gene-related peptide (CGRP) and post-ganglionic sympathetic fibers were labeled with an antibody raised against tyrosine hydroxylase (TH). RT97, CGRP, and TH immunoreactive fibers were present in parenchyma of the head, body and tail of the pancreas with the relative density of both RT97 and CGRP expressing fibers being head>body>tail, whereas for TH, a relatively even distribution was observed. In all three regions of the pancreas, RT97 fibers were associated mainly with large blood vessels, the CGRP fibers were associated with the large- and medium-sized blood vessels and the TH were associated with the large- and medium-sized blood vessels as well as capillaries. In addition to this extensive set of sensory and sympathetic nerve fibers that terminate in the pancreas, there were large bundles of en passant nerve fibers in the dorsal region of the pancreas that expressed RT97 or CGRP and were associated with the superior mesenteric plexus. These data suggest the pancreas receives a significant sensory and sympathetic innervation. Understanding the factors and disease states that sensitize and/or directly excite the nerve fibers that terminate in the pancreas as well as those that are en passant may aid in the development of therapies that more effectively modulate the pain that frequently accompanies diseases of the pancreas, such as pancreatitis and pancreatic cancer.

Animals↗

Effect of aerobic exercise training on blood pressure sensitivity to dietary sodium in older hypertensives.

Although aerobic exercise training has been shown to lower blood pressure (BP) in older adults, its effect on BP sensitivity to dietary sodium (Na(+)) is unknown. Therefore, the present study was undertaken to examine the effect of aerobic exercise training on BP sensitivity to dietary Na(+) in older hypertensive individuals. Blood pressure was measured after 8 days of low (20 mEq) and high (200 mEq) Na(+) diets in 31 older (63+/-7 years, mean+/-standard deviation), hypertensive (152+/-11/88+/-5 mm Hg) individuals at baseline and following 6 months of aerobic exercise training (at 75% VO(2)max, 3 times/week, 40 min/session). Subjects were grouped on the basis of the difference in mean arterial BP (MAP) between diets (Na(+) sensitive: >or=5 mm Hg increase in MAP on high Na(+), n=20; Na(+) resistant: <5 mm Hg increase in MAP on the high Na(+) diet, n=11). Following 6 months of aerobic exercise training, there was a significant increase in maximal aerobic capacity (VO(2)max: 18.3+/-3.8 vs 20.7+/-4.2 ml/kg/min, P<0.017). Aerobic exercise training had a significant (P=0.02) effect on Na(+) sensitivity status, with the proportion of Na(+)-resistant individuals increasing from 35% at baseline to 61% following the 6-month aerobic exercise training programme. This study demonstrates the importance of physical activity on BP sensitivity to dietary Na(+).

Aging↗

Antenatal psychiatric illness and adequacy of prenatal care in an ethnically diverse inner-city obstetric population.

OBJECTIVE: This study assessed the prevalence of antenatal psychiatric illness in low-income, ethnically diverse patients in an urban obstetric clinic and examined associations between positive psychiatric screens and inadequate utilization of prenatal care. METHODS: Bilingual research assistants administered the Primary Care Evaluation of Mental Disorders Patient Health Questionnaire and the Mood Disorder Questionnaire to 154 English- and Spanish-speaking pregnant patients attending routine prenatal visits. We assessed associations between patient characteristics, current and past psychiatric diagnoses, and utilization of prenatal care. RESULTS: Forty-five (29%) women screened positive for criteria for current psychiatric disorders with the highest rates for major or minor depression (26%) and anxiety disorders (10%). Inadequate prenatal care utilization was significantly associated with past psychiatric history and domestic abuse in the last year, but not with current psychiatric diagnosis, alcohol abuse, age, primiparity, marital status, receipt of government assistance, or unplanned pregnancy. Even after adjustment for possible confounding risk factors (e.g. past substance abuse, single marital status, unstable housing, education less than high school, and having other children), past psychiatric history was still significantly associated with inadequate prenatal care utilization and delayed initiation of care. CONCLUSIONS: A high percentage of disadvantaged pregnant women meet screening criteria for psychiatric disorders when screened during routine prenatal visits. Screening for past psychiatric history in routine prenatal visits could identify patients at risk for inadequate utilization of prenatal care.

Adult↗

Incidence of erectile dysfunction after open abdominal aortic aneurysm repair.

The aim of this study is to document the incidence of erectile dysfunction (ED) following open abdominal aortic aneurysm (AAA) repair using a modified International Index of Erectile Function questionnaire (IIEF). An IIEF was mailed to 175 married male patients (mean age +/- SD: 71 +/- 8 years) who had an open AAA repair by one of four board-certified vascular surgeons between 1994 and 1998. The IIEFs were anonymous and asked patients to recall their sexual function before and 3 months after repair. ED was defined in patients with IIEF scores <11 (range 1-30). The overall response rate was 39% (68/175). A comparison of the IIEF results showed that 67/68 patients reported worsening erectile function (p < 0.00001); one respondent reported improved erectile function. On the basis of the IIEF scores, 20/68 patients (29%) were found to have ED and 48/68 patients (71%) had normal function prior to repair. Of the 48 patients with normal function prior to surgery, 83% (40/48) had ED after surgery. ED rates were similar between tube grafts 82% (23/28) and bifurcated grafts 85% (17/20) p = ns. The ED rate after open AAA repair is alarmingly high and prospective follow-up with IIEF will be necessary to better assess true ED rates after conventional open AAA repair.

Aged↗

Quantitative sensory testing: effect of site and pressure on vibration thresholds.

OBJECTIVE: To determine the effect of different sites and locally applied pressure on vibration thresholds. METHODS: Vibration thresholds were compared in 47 normal volunteers at 3 sites of the index finger (pulp, dorsum of the middle phalanx and nail) and at two sites of the great toe (dorsum of the proximal phalanx and nail). The effect of local pressure (30, 50 and 100 g/1.22 cm(2)) were compared in 41 subjects at the dorsum of the middle phalanx of the index finger and the proximal phalanx of the great toe. RESULTS: The hand was more sensitive than the foot for vibration. There were no significant differences in vibration thresholds at different sites of the index finger and different sites of the great toe. The pulp of the index finger yielded the least inter-individual variation. Testing under 30 and 50 g/1.22 cm(2) of pressure yielded equal vibration thresholds. Vibration threshold was higher when tested under 100 g/1.22 cm(2) at the index finger but not the great toe. This difference was small and clinically negligible. CONCLUSION: Testing of vibration thresholds in normal subjects can be adequately conducted at several sites of the index finger and the great toe. The test can be adequately done under low pressure of 30-50 g/1.22 cm(2).

Adult↗

Quantitative sensory testing: effect of site and skin temperature on thermal thresholds.

OBJECTIVE: To determine the effect of different sites and local skin temperature on thermal thresholds. METHODS: Cool and warm detection and cold and heat pain thresholds were compared in 46 normal volunteers at the thenar eminence (TE), dorsum of the hand (DH), volar surface of the wrist (VW) and dorsum of the foot (DF). RESULTS: The hand is more sensitive than the foot for cool and warm. TE is more sensitive for warm than DH and VW but the difference is clinically negligible. DH and VW are equally sensitive to warm. TE, DH, and VW are equally sensitive to cool. Inter-individual variance is smallest at TE. Warm and cool thresholds are independent of local skin temperature (range of 27-37 degrees C). TE is less sensitive for cold pain but otherwise the hand and the foot are equally sensitive to thermal pain. CONCLUSION: Testing of thermal thresholds in normal subjects can be adequately conducted at several sites at the hand, however, TE is preferred given the small inter-individual variability. TE may be preferred for evaluating hyperalgesia to cold given its higher threshold. Warming or cooling of the skin is unnecessary within the range normally encountered in routine clinical evaluation.

Adult↗

Comparing patency rates between external iliac and common iliac artery stents.

PURPOSE: Placement of intraluminal stents in the common iliac artery (CIA) and external iliac artery (EIA) has become an accepted therapy for treating localized arterial stenoses. The purpose of this study was to compare anatomic patency rates of stents placed in the EIA and CIA for occlusive disease. METHODS: A radiologic computer database was used to identify 69 consecutive male patients at the Minneapolis Veterans Affairs Medical Center from February 1, 1993, through January 31, 1999, who underwent placement of 98 stents (82 Wallstents and 16 Palmaz stents) for physiologically significant iliac artery occlusive disease and varying degrees of chronic limb ischemia. Patients were followed up with surveillance duplex ultrasound scanning examinations 1 day after procedure, 3 months after procedure, and then at 6-month intervals after stent placement. Follow-up angiograms were performed for patients with duplex ultrasound scans that revealed velocities greater than 300 cm/s. Patient risk factors, iliac artery runoff, concomitant outflow procedures, and anatomic patency rates were compared between patients receiving EIA stents and those receiving CIA stents. RESULTS: The mean age for the EIA stent group was 69 +/- 1 years versus 66 +/- 1 years (P =.03) for the CIA stent group. Mean follow-up was 21.4 +/- 2.1 months (+/- SE) for all patients. Patients with EIA stents had more ischemic lower limbs when compared with patients who had CIA stents (P =.05). No differences were found between groups in risk factor analysis (P = not significant). Lesion lengths were similar between groups: EIA, 4.6 +/- 0.6 cm, and CIA, 5. 3 +/- 0.8 cm (P = not significant). The following differences were noted on primary patency rates (EIA group vs CIA group): 1 year (93% vs 88%), 2 years (91% vs 85%), and 3 years (90% vs 78%) (Cox proportional hazards; P =.13). CONCLUSIONS: Anatomic patency rates for EIA and CIA stents appear to be similar despite the fact that patients with EIA stents were older and had more ischemic limbs compared with the patients who had CIA stents.

Aged↗

Wound infection after infrainguinal bypass operations: multivariate analysis of putative risk factors.

Reported wound infection rates for infrainguinal bypass operations range from 17% to 44%, but there is limited appreciation of which characteristics of patients or operations are reliable markers of increased wound infection risk. The purpose of the present study was to analyze all wound infections observed after infrainguinal bypass operations during 20 years of practice in a large teaching institution. Independent risk factors for wound infection development were identified. During the 20-year period ending 31 December, 1997, 978 male patients underwent infrainguinal bypass operations at the Minneapolis Department of Veterans Affairs Medical Center. Wound infections complicated the recovery of 129 of these patients during a 30-day postoperative surveillance interval. Multivariate logistic regression analysis was used to test the association between wound infection occurrence and putative risk factors that were either features of patients or characteristics of the operations. The following variables were examined: obesity, prosthetic graft placement, diabetes mellitus, steroid use, anticoagulation use, length of preoperative hospital stay, development of incisional hematoma, duration of operation, and the preoperative presence of a non-healing wound in the extremity being revascularized. The overall wound infection rate was 13.2% (129/978). In a final logistic regression model, obesity was a significant and independent predictor of wound infection (Relative Risk 2.6, 95% confidence interval, 1.35-4.90), as was development of a post-operative incisional hematoma (Relative Risk 6.44, 95% confidence interval, 2.95-14.08). No other explanatory variable was significantly associated with wound infection development.

Aged↗

Superficial femoral popliteal vein: An anatomic study.

OBJECTIVE: The superficial femoral popliteal vein (SFPV) has been used as an alternative conduit for both arterial and venous reconstructive surgery. Its popularity continues to grow, despite concern about the potential for venous morbidity after harvest. The purpose of this study was to determine an anatomic "safe" length of SFPV for harvest, assuming that the preservation of at least one valve and one significant collateral vein in the remaining popliteal vein (PV) segment can minimize venous morbidity. METHODS: Forty-four SFPVs were harvested from 39 cadaveric specimens. The length of both the superficial femoral vein (SFV) and PV was measured, and the number and location of valves and significant side branches (more than 2 mm in diameter) of the PV were measured. The Student two-tailed t test was used as a means of comparing vein lengths between the sexes. Correlation coefficients were determined for the effect of patient height on vein length, stratified by means of sex. RESULTS: Vein length (SFV mean, 24.4 +/- 4 cm; PV mean, 18.8 +/- 4 cm) varied with sex (male SFV mean, 28.1 +/- 5 cm; male PV mean, 21. 5 +/- 3 cm; female SFV mean, 22.6 +/- 4 cm; female PV mean, 18.4 +/- 3 cm; P =.01). Valve number (mean, 1.8 +/- 0.5) and location and collateral vein number (mean, 5 +/- 1.8) and location were variable and independent of height or sex. CONCLUSION: An anatomic "safe" length of SFPV for harvest to minimize venous morbidity would include all the SFV and 12 cm of PV in 95% of women and 15 cm of PV in 95% of men. We found that the male sex was a significant determinant for a longer safe length of vein that can be harvested.

Cadaver↗

Delayed behavioral effects following intrahippocampal injection of aggregated A beta (1-42).

Beta amyloid protein (A beta) is the major extracellular component of Alzheimer's disease (AD) plaques. In the current study, A beta (1-42) was aggregated in vitro using a method which produces A beta aggregates similar to those found in the AD brain. Twelve male Sprague-Dawley rats were trained in two-lever operant chambers under an alternating lever cyclic-ratio (ALCR) schedule. When performance was stable on the ALCR schedule, six subjects were injected (bilaterally into the CA3 area of the dorsal hippocampus) with 5.0 microliters aggregated A beta in suspension, and the remaining six subjects were injected with 5.0 microliters sterile water. Behavioral testing resumed 5 days after surgery and continued for 90 days post-injection. Aggregated A beta injection did not affect the number of lever switching errors made in a daily session but did affect the number of incorrect lever response perseverations. After approximately 30 days post-injection, aggregated A beta injection detrimentally affected ability to track the changing parameters of the schedule, and decreased the efficiency by which subjects obtained reinforcers. From approximately day 50 post-injection onward, A beta-injected subjects demonstrated significantly higher numbers of incorrect lever response perseverations than did sterile water-injected subjects. These effects appeared to be central rather than peripheral, as A beta injection did not decrease running response rates under the ALCR schedule. The delayed onset of behavioral effects seen in this and other behavioral studies may be a result of a cascade of potentially harmful responses induced through glial activation following aggregated A beta injection.

Amyloid beta-Peptides↗

The role of the fusiform gyrus in successful encoding of face stimuli.

PET was used to measure regional cerebral blood flow (rCBF) while memorizing pictures of unfamiliar human faces presented one at a time (FaceMemory). Other conditions included: (1) FaceRepeat-memorization of four individual faces presented repeatedly; (2) FaceWatching-viewing passively single faces without overt memory demands; and (3) Scrambled-counting dots superimposed on pictures of scrambled faces. After each FaceMemory condition and after the final FaceWatching condition scan, recall was tested by measuring face recognition. Contrasting FaceMemory and Scrambled conditions revealed several temporal activations: right midfusiform and bilateral anterior fusiform gyri. Contrasting FaceWatching and Scrambled conditions showed bilateral activation in the temporal poles and in the anterior fusiform gyri. No hippocampal activation arose from any contrast. Region of interest analyses on the above areas showed correlations with performance: (1) only rCBF in the right midfusiform correlated positively with encoding during the FaceMemory and FaceWatching conditions; (2) in the right temporal polar cortex rCBF decreased during FaceMemory and correlated positively with performance, whereas rCBF increased during FaceWatching and correlated negatively with incidental performance; and (3) activity in the anterior fusiform gyri remained constant across the conditions of FaceMemory, FaceRepeat, FaceWatching, and Scrambled and was uncorrelated with performance. These data suggest an expanded mnemonic role for the right midfusiform in depth of processing/encoding of face information, temporal polar cortex in face perception and recognition, and anterior fusiform activity in featural visual feature processing.

Adult↗

Alpha tocopherol in CSF of subjects taking high-dose vitamin E in the DATATOP study. Parkinson Study Group.

Alpha-Tocopherol concentrations were determined in the CSF of patients with early untreated Parkinson's disease receiving 2,000 IU vitamin E orally per day. After treatment the concentrations increased significantly (p < 0.001) by 76+/-10 (SE)%. The net increases in CSF alpha-tocopherol concentrations after treatment showed a significant positive correlation with the number of days of vitamin E ingestion (p < 0.001). Thus, high-dose vitamin E treatment results in elevating CSF vitamin E levels and possibly brain vitamin E levels.

Antioxidants↗

Phenomenological and pharmacological study of provoked obsessive/anxiety symptoms in obsessive-compulsive disorder: a preliminary study.

BACKGROUND: Inclusion of obsessive-compulsive disorder (OCD) as an anxiety disorder in DSM-i.v. assumes that anxiety is the primary symptom of OCD; however, persuasive empirical evidence in support of this view has not been presented yet. In the present study we hypothesized that provoked anxiety symptoms respond better to intravenous diazepam than would provoked obsessions. We, therefore, reasoned that anxiety symptoms are secondary symptoms of OCD. METHODS: To test the hypothesis we designed a double-blind, randomized, placebo-controlled crossover study. Patients underwent four experimental conditions in which the sequence of symptom provocation and i.v. injection of (placebo or diazepam) were alternated. Baseline and i.v. injection-induced symptom changes were assessed using visual analogs. RESULTS: Obsessions and anxiety correlated strongly for all four experimental conditions in which the sequence of the symptom provocation and diazepam i.v. injections was alternated. i.v. diazepam injection before and after symptom provocation failed to preferentially modulate anxiety symptoms over obsessions. Unexpectedly, in the group in which i.v. diazepam injection preceded the symptom provocation, reduction of mean obsessions was even more pronounced. CONCLUSIONS: Strong correlations between anxiety and obsessions at baseline, during symptom provocation, and after i.v. diazepam infusion suggest that anxiety and obsessions are tightly coupled phenomena in OCD.

Adult↗

Noxious cutaneous thermal stimuli induce a graded release of endogenous substance P in the spinal cord: imaging peptide action in vivo.

Dorsal root ganglia (DRG) neurons synthesize and transport substance P (SP) to the spinal cord where it is released in response to intense noxious somatosensory stimuli. We have shown previously that SP release in vivo causes a rapid and reversible internalization of SP receptors (SPRs) in dorsal horn neurons, which may provide a pharmacologically specific image of neurons activated by SP. Here, we report that noxious heat (43 degrees, 48 degrees, and 55 degrees C) and cold (10 degrees, 0 degrees, -10 degrees, and -20 degrees C) stimuli, but not innocuous warm (38 degrees C) and cold (20 degrees C) stimuli, applied to the hindpaw of anesthetized rats induce SPR internalization in spinal cord neurons that is graded with respect to the intensity of the thermal stimulus. Thus, with increasing stimulus intensities, both the total number of SPR+ lamina I neurons showing SPR internalization and the number of internalized SPR+ endosomes within each SPR immunoreactive neuron showed a significant increase. These data suggest that thermal stimuli induce a graded release of SP from primary afferent terminals and that agonist dependent receptor endocytosis provides evidence of a spatially and pharmacologically unique "neurochemical signature" after specific somatosensory stimuli.

Animals↗

Alternating lever cyclic-ratio schedule analysis of the effects of atropine sulfate.

Cholinergic dysfunction has been implicated in the behavioral and memory impairment that is the hallmark of conditions such as delirium and Alzheimer's Disease. Anticholinergic drugs have been widely used in procedures designed to mimic aspects of the pathology of these conditions in rats. Procedures in use vary widely in sensitivity and behavioral specificity and may be confounded by administration of high drug doses that may not be physiologically relevant. The current study proposes the use of rats responding on an alternating lever cyclic-ratio schedule to study the effects of the anticholinergic compound atropine sulfate. This procedure enables simultaneous measurement of anticipatory ratio tracking (postreinforcement pause durations), perseverations (lever switching errors), and nonspecific peripheral drug effects (running response rates). Results of this study suggest that the schedule is sensitive to low drug doses (0.1-1.0 mg/kg atropine), measures the ability to track changing ratio conditions and to execute lever alternation, and allows for monitoring of peripheral drug effects during behavioral testing. The procedure's sensitivity and low effective dose range may make it useful in the study of behaviors related to anticholinergic effects.

Animals↗

Behavioral effects of naloxone on neuropeptide Y-induced feeding.

We evaluated the effect of naloxone on neuropeptide Y (NPY)-induced feeding behavior using two methods; operant chambers and observational analysis. In the first study rats were trained on a FR 80 (first pellet) FR 3 (subsequent pellets) reinforcement schedule. Following training, rats were injected with NPY (intraventricular, 5 micrograms) and various doses of naloxone (subcutaneous, 0, 0.1, 0.3, 1, 3, and 10 mg/kg). NPY significantly increased the number of pellets consumed during the one hour session and naloxone (1, 3, and 10 mg/kg) blocked this effect. NPY failed to alter the time to the first response, but did decrease the time needed to complete the first ratio (FR 80). Naloxone (3 and 10 mg/kg) increased the latency to the first response and blocked NPY's effect on completion of the first ratio. In the second study, we observed rats continually following injection of saline. NPY (5 micrograms i.c.v.) and/or naloxone (1 mg/kg s.c.). NPY increased food intake during the 1-h session and naloxone blocked this effect. NPY decreased the latency to eat, but naloxone failed to significantly antagonize this effect. The amount of time spent eating was greater in the NPY group compared to the saline group and naloxone antagonized this effect. Lag sequential analysis indicated that NPY induced a move-eat-move behavioral sequence that disappeared following naloxone administration. These data lend support to the notion that opioids are involved in maintenance of NPY-induced feeding but affect meal initiation in a minor way. Only relatively high doses of naloxone (3 and 10 mg/kg) altered NPY-induced changes in meal initiation.

Animals↗

Clean intermittent catheterization: safe, cost-effective bladder management for male residents of VA nursing homes.

OBJECTIVES: To compare the safety and cost of clean versus sterile intermittent bladder catheterization in male nursing home residents. To provide evidence to support the hypothesis that intermittent catheterization is a valid, alternative method of bladder management in male residents of long-term care in whom urinary retention is a documented problem. DESIGN: Randomized clinical trial. SETTING: Three long-term care sites having predominantly male populations. PARTICIPANTS: Eighty male veterans, residents of three long-term care facilities, ranging in age from 36 to 96 years with a mean age of 72. INTERVENTIONS: Standardized procedures for clean and sterile intermittent catheterization (IC) were implemented by staff nurses at each site. Patients were randomized into clean and sterile IC groups. Nursing time and catheterization equipment usage were recorded using bar code readers. Clinical data were collected from the medical chart. Treatment of urinary tract infection was prescribed by the medical personnel responsible for each individual resident. MEASUREMENTS: We compared the number of treatment episodes for symptomatic bacteriuria between groups randomized to receive either clean or sterile intermittent catheterization. Laboratory analysis of blood and urine was done on predetermined days. Control variables were research site and patient history of urinary tract infection within the last 6 months. A cost comparison of nursing time and equipment usage for the two catheterization techniques was also performed. RESULTS: No significant differences were found between clean and sterile groups with regard to number of treatment episodes, time to first infection, type of organism cultured, or cost of antibiotic treatment. The cost of sterile technique was considerably higher both in terms of nursing time and supplies. CONCLUSIONS: Findings from this study demonstrate that clean technique intermittent catheterization is a safe and cost-effective bladder management technique with male, nursing home residents, despite the frailty of this high risk population. An annual savings of approximately $1460 per patient in nursing time and catheterization supplies could be anticipated if a patient were catheterized an average of four times per day substituting clean IC technique for sterile IC technique.

Adult↗

Postural effects on intra-abdominal pressure during Valsalva maneuver.

When lifting heavy loads, trunk muscle contraction converts the abdominal and thoracic cavities into a nearly rigid-walled cylinder that provides increased extrinsic stability and allows partial transfer of load away from the spine. Because twisting is a common mechanism of low-back injuries, this study was undertaken to determine if trunk rotation results in a decrease in the extrinsic stability of the spine. We studied the effects of changes in trunk posture on intra-abdominal pressure generated during a maximum effort Valsalva's maneuver (IAP max) in eight healthy volunteers. IAP max during standing combined with trunk rotation was found to be significantly lower than IAP max during standing straight (p < 0.05). IAP max during forward flexion combined with trunk rotation was significantly lower than during forward flexion (p < 0.01). The results of our study indicate that trunk rotation adversely effects the ability to perform a Valsalva's maneuver. We conclude that extrinsic stability of the spine is at a biomechanical disadvantage when the trunk is rotated and thus may be a contributing factor to twisting-type back injuries.

Abdomen↗