Conventional Versus Neutral Positioning in Central Neurological Disease

A Multicenter Randomized Controlled Trial

Background: Severe immobility due to lesions of the brain necessitates therapeutic positioning over the long term. There is little scientific evidence concerning the efficacy of different positioning methods. This clinical trial compares the effects of conventional positioning (CON) with those of positioning in neutral (LiN).

Methods: A prospective, multicenter, investigator-blinded, randomized, controlled trial was performed on a total of 218 non-ambulatory patients (underlying disease: stroke, 141 patients; hypoxic brain damage, 28; traumatic brain injury, 20; other, 29). The subjects were randomly assigned to either LiN (105 patients) or CON (113 patients) and stratified within each of these two positioning concepts to five different positions. They remained in the assigned positions for two hours. The primary endpoint was change in the passive range of motion (PROM) of the hip joints. Secondary endpoints were change in the PROM of the shoulder joints and patient comfort.

Results: Patients in the LiN group had a significantly better PROM of the hips after positioning than those in the CON group (difference, 12.84°; p<0.001; 95% confidence interval [CI], 5.72°–19.96°). The same was true for PROM of shoulder flexion (11.85°; p<0.001; 95% CI, 4.50°–19.19°) and external rotation (7.08°; p<0.001; 95% CI: 2.70°–11.47°). 81% of patients in the LiN group reported their comfort level as good, compared to only 38% in the CON group (p<0.001).

Conclusion: Positioning severely immobilized patients in LiN for two hours improved passive hip and shoulder mobility and patient comfort compared to conventional positioning. Further studies are needed to determine whether prolonged LiN positioning might improve rehabilitation and quality of life, prevent pressure sores, or ease nursing care.

Various neurologic conditions produce large numbers of patients with severe immobility. In Germany, new cases of stroke alone account for about 45 000 severely immobilized patients each year (1). These patients need to be regularly positioned and repositioned over a long period. This is part of routine nursing care in acute wards and during rehabilitation. Effective patient positioning reduces patient discomfort and prevents secondary complications including pressure sores and pneumonia (2, 3). Prone position and backrest elevation have positive effects in patients with lung problems, but can lead to pressure ulcers (4). Compared to lying flat, upright positioning can lead to a wide range of individual reactions (5). This may be the reason why there is still no agreement among nurses and therapists about the best positions for stroke patients (6). Equally unclear is how often the position should be changed in order to prevent pressure ulcers (7).

During the rehabilitation period, effective patient positioning can enhance functional recovery, prevent contractures, and normalize muscle tone (8). Conversely, suboptimal positioning can reduce passive range of motion (PROM). However, the efficacy of various positions has rarely been studied before now, and to date no systematic comparison has been carried out of the efficacy of various positioning concepts.

Conventional positioning (CON) is performed by changing the patient's position every 2–3 hours between different supine, prone or lateral positions by using positioning material placed under defined body parts. The positioning is done with little consideration of the position of the body segments in relation to each other (9). By contrast, in positioning in neutral (Lagerung in Neutralstellung, LiN), an important part is played by the alignment of the body parts. Attention is focused on ensuring that muscle groups are neither shortened nor lengthened, and that stability is provided to paretic body parts (Pickenbrock H, et al.: Therapeutic effects of positioning patients with CNS-lesion—RCT. 2014; WCNR: ref. no. 95, poster no. PP-525 http://wcnr2014.org/abstract_results-46.html [last accessed 8 July 2014]; further comparative details are shown in Figure 1) (10). LiN requires more positioning material, such as bedding and pillows, than CON. In combination with special stabilizing techniques, the materials are thought to allow patients to relax. At the same time, they offer a much broader base of support than CON by distributing the patient’s body weight more evenly. The resulting relief of load on heels, ischium, and sacrum reduces the risk of pressure ulcers at these places (11).

Figure 1

Example of conventional positioning (CON) and positioning in neutral (LiN) for a patient lying on the right side

The aim of the present study was to compare the efficacy of LiN and CON respectively in severely immobile patients. Since contractures have a negative effect on mobility and the outcome of rehabilitation, and since pain due to reduced PROM makes nursing more difficult, we investigated the effect of positioning on PROM (12–14). We were also interested in patients’ sense of well-being, and therefore also assessed the comfort provided by the two different positioning concepts. We hypothesized that LiN would have stronger effects on both PROM and comfort.

Methods

This multicenter, prospective, randomized, controlled study was carried out in 22 centers in Germany and Austria (eTable 1). In each center, a trained therapist or nurse was responsible for ensuring that the study protocol (eSupplement under “Methods”) was followed. The investigators involved in the study were members of the association LiN-Arge e.V., a not-for-profit organization, the aim of which is to disseminate knowledge of the LiN approach.

eTable 1

Participating centers

Table

Demographic characteristics and baseline values of clinical characteristics of study patients

The Research Ethics Committee of the Westfalen–Lippe Medical Association and the Medical Faculty of the Westfalian Wilhelms University Muenster approved the study. The study was registered with the German Clinical Trials Register (15).

Sample size calculation was based on a pilot study of 12 acute stroke patients (mean standard deviation for hip flexion: 7.5° ± 15.7° for 6 LiN patients and 3.0° ± 4.5° for 6 CON patients).

For a two-sided type one error of 5% and a power of 80%, 106 patients per group were calculated as the required sample size using the t test with Satterthwaite approximation.

Prior to the study, a Microsoft Excel file was created for the purpose of randomization. The first column listed the various conditions (five positions each in LiN and CON: supine, 30° side lying right or left, 90° side lying right or left). Participants’ numbers were listed in the second column. In the third column, a random number was produced for each participant using the function =Rand(). Participant numbers were then sorted according to the randomly generated numbers and each was assigned to one of the conditions (16).

The study was carried out without external funding. All authors vouch for the accuracy of data acquisition, processing and analysis, and assure compliance with the study protocol.

Patients

The patients were recruited from stroke units, intensive care units, early rehabilitation centers, geriatric rehabilitation centers, secondary rehabilitation centers and nursing homes. Inclusion criteria were a minimum age of 18 years and central paresis with severe disability (non-ambulatory patients: 4 and 5 on the Modified Rankin Scale [17]).

Exclusion criteria were fixed contractures, considerable agitation, and the need of backrest elevation. Patients were included in the study only if they or their legal custodians had provided written informed consent before start of the study. A physician ascertained the eligibility of enrolled patients.

Endpoints

The primary endpoint of the study was change in the passive range of motion (PROM) of the hip joints (before–after positioning). Secondary endpoints were change in shoulder flexion and external rotation PROM and patient comfort. PROM was measured using a standard goniometer before the position (LiN or CON) was started and after 2 hours’ lying in the respective position (for details, see eSupplement, “Methods,” and eFigures 1–3). Patient comfort was recorded after the intervention from those patients who were able to communicate, using a three-point scale (“good”, “fair”, and “bad”, each visualized by an emoticon).

eFigure 1

Measuring flexion in the hip

eFigure 2

Measuring flexion in the shoulder

eFigure 3

Measuring external rotation of the shoulder

Procedure

At first the patients lay on their back with only a pillow under their head; that is, they were not positioned according to either of the approaches. The investigator, who had been trained to perform a standardized procedure prior to the study and was not involved in the daily routine, measured the PROM and then left the room. Next, a therapist or nurse positioned the patient in the allocated LiN or CON position. After 2 hours, the patient was returned by this person to the starting position. The investigator then measured the PROM and recorded the comfort score. This procedure ensured that the investigator was blinded to the patient positioning.

Intervention

In the present study, the patient positions used were those most commonly in use in Western Europe: supine, 30° side lying right or left and 90° side lying right or left. To ensure standardized intervention, participating centers were provided with worksheets describing each of the procedures. These worksheets can be obtained on request from the first author.

For LiN, the original worksheets of the LiN approach were used. For CON, the procedure was derived from the literature (18–21). In order not to exert any additional effects on the PROM, all measures performed during positioning had to be carried out passively and large movements of the extremities had to be avoided. After being positioned, patients were asked to stay in this position for 2 hours, but were also told that they were permitted to change their position at any time.

Statistics

SAS 9.3 software was used for the statistical analysis. Category variables were compared between groups using either the χ² test or, in the case of cell frequencies <5, using Fisher’s exact test. For metric variables, the two treatment groups were compared assuming a normal distribution and equal variance using the t test for two independent samples. When normal distribution and unequal variance were assumed, that t test was used with Satterthwaite approximation. If normal distribution could not be assumed, the Mann–Whitney U test was used.

The primary analysis was performed for the intention-to-treat population. In this case, this means that patients who spontaneously repositioned themselves were analyzed as randomized. The two-sided alpha error was set at 5%.

For the primary analysis, ANCOVA (analysis of covariance) was used with change (before–after positioning) of PROM of the hips (Δ_{PROM hips}) as dependent variable (mean of the left and the right side). The independent variables were type of positioning (2 conditions: LiN, CON) and, because of stratified randomization, the position (5 conditions: supine position, 30° side lying right or left, and 90° side lying right or left). Baseline PROM values were included as covariates. Interaction between independent variables was also included in the model. For sensitivity analyses, a complete case analysis and nonparametric ANCOVA were performed.

As a secondary analysis, shoulder PROM values were compared in the same procedure as described above. To compare comfort between the groups, the χ² test was used. All results are presented in accordance with the CONSORT statement (22).

Results

Patients

From October 2010 to October 2012, 454 patients were screened for eligibility. A total of 218 patients were randomized and assigned to the intended interventions (Figure 2). Patient recruitment ceased when the calculated group size was reached. The Table shows the baseline values in the study population, including the incidence of the various causes of the neurological disorders. Further details are given in eTable 2. In terms of demographic variables, there were no relevant differences between the LiN and the CON group. Slight differences (p<0.2) were seen only in relation to age and duration of illness ( 6 months). If these parameters were included in the model in a sensitivity analysis, the results were robust (further details in eSupplement under “Results”).

Figure 2

Enrollment and randomization of patients

eTable 2

Distribution of diseases

Intervention

The patients were equally distributed over the five positions (p = 0.92; details in eTable 3). In the LiN group, six patients (5.7%) had left their position; in the CON group, nine (7.9%). One patient in the LiN group had to be propped up due to orthopnea. In one patient in the CON group, the data after the positioning were missing because of intervening digestive problems. For this patient, the baseline observations were carried forward.

eTable 3

Distribution of positions. including the number of incomplete interventions

Primary endpoint

The ANCOVA showed a statistically significant improvement in hip PROM after 2 hours in position in the LiN group (change from baseline: Δ_{PROM hips} ) compared to the CON group (Δ_{PROM hips} [LiN] – Δ_{PROM hips} [CON] = 12.84°, p<0.001; 95% confidence interval [95% CI]: 5.72° to 19.96°). Mean values and 95% CI for the various subgroups are shown in Figure 3 and eTable 4.” The positions (supine, 30° side lying right or left, 90° side lying right or left) had no relevant effect (p = 0.119). Likewise, no relevant interaction was shown between the two approaches and the positions (p = 0.374). The effect of the baseline measurements, on the other hand, was significant. Lower baseline values predicted stronger increases in PROM (estimate = –0.11, 95% CI: –0.20° to –0.02°; p = 0.013).

Figure 3

Primary endpoint: change in passive range of motion (PROM) of hip joints, in degrees

eTable 4

PROM values of hips and shoulders at baseline, separately for right and left

Sensitivity analysis demonstrated the robustness of the results (p ≤ 0.001 in all cases; Δ_{PROM hips} [LiN] – Δ_{PROM hips} [CON] between 7.31° and 13.41°).

Secondary endpoints

The effects on shoulder mobility were found to be similar to those on hip mobility. For shoulder flexion, the difference between LiN and CON Δ_{PROM shoulders} [LiN] – Δ_{PROM shoulders} [CON] = 11.85° (95% CI: 4.50° to 19.19°), and for external rotation of the shoulders it was 7.08° (95% CI: 2.70° to 11.47°). Further details are given in eTable 5.

eTable 5

Descriptive measures of change in PROM (before–after positioning) in the different positions

Seventy-nine patients were unable to communicate, and an answer from one patient was missing. Hence, n = 138 patients (LiN: n = 69, CON: n = 69) were able to answer the question about the comfort of the applied position. Comfort was assessed as significantly better for the LiN approach than for the CON approach (p<0.001; Figure 4).

Figure 4

Secondary endpoint: Patient comfort in LiN and CON

Additional analyses relating to the effects of positioning on the patient’s more affected versus less affected body side are given in the eSupplement under “Additional analyses” and in eTables 6 and 7.

eTable 6

Cross reference table for more-affected side and side lain on in patients with hemiplegia

eTable 7

Duration of illness ≤ versus >45 days and ≤ versus >182 days

Discussion

Consistently carried out positioning and repositioning of patients with acquired brain damage and severe immobility is of great importance. These patients need effective postural management to enhance and reinforce recovery of function (23). Currently recommended forms of positioning following conventional principles (CON) are rarely used in practice (24–26). There is a lack of studies of the influence of positioning on functional recovery.

The present study shows that positioning patients in a neutral position (LiN) is easily applied within daily clinical routine, can increase the passive mobility of hip and shoulder joints, and is experienced by the patients as noticeably more comfortable than a CON. The improved comfort especially means that LiN should be considered not just for patients with neurological impairment, but also for immobilized patients in intensive care or in the geriatric unit. The principles of LiN (alignment, support and stabilization of the body parts) can be applied not just in the positions studied here—lying on the back or sides—but also in other positions such as lying prone, 135° tilted, or sitting up in bed or on a chair.

Since manual goniometer measurements have recently been criticized for problematic inter-rater reliability, we requested pre/post measurements by the same assessor. To compensate for possible inaccuracies of manual goniometer measurements, we required relevance thresholds of 8° for hip flexion, 7° for shoulder flexion, and 11° for external shoulder rotation (27, 28). All our therapeutic effects except for shoulder rotation were well above this threshold.

The intervention time was 2 hours, the shortest time recommended for preventing any form of pressure ulcer (2, 3). It may be assumed that longer intervention times would result in even stronger effects.

We ruled out the possibility that any conversations between the patients and the assessors might explain the results obtained. The analysis carried out on only those patients who were unable to communicate showed a similar effect to the primary analysis (n = 79; Δ_{PROM hips} [LiN] – Δ_{PROM hips} [CON] = 13.14, p = 0.03 [eSupplement, “Additional analyses”].

Previous clinical studies of patient positioning aimed at improving shoulder mobility in stroke patients have been unable to show any improvement in this parameter (29). This may be due to a variety of methodological differences to the present study. In the first place, the earlier studies positioned only the hemiplegic arm, not the whole body. Secondly, the arms were placed in a stretched position in order to counteract muscular shortening. We, by contrast, placed all the segments of the body including the arms in such a way that muscles were neither stretched nor shortened.

Various factors may contribute to the beneficial effects of LiN on passive mobility and patient comfort. First, the large support area and the stabilization applied allow the patient relax, and hence both perceived comfort and PROM improve. On the neurophysiological level, it is likely that, because overstretching and shortening of the musculature are avoided, changes take place in tactile, proprioceptive, and nociceptive afferences are altered, which may have an inhibitory effect, via spinal reflex mechanisms, on muscular hyperactivity.

Summary

The intervention time was limited to 2 hours. Due to this, a number of questions remain unanswered:

• Can LiN reduce the risk of pressure ulcers developing?
• What are the long-term effects of this positioning method?
• Could, for example, using LiN for several weeks have an effect on patients’ levels of activity, participation, or quality of life?

We hypothesize that LiN could have a positive influence on these parameters if the positioning is carried out over many hours of the day and for as long as the patient is unable to move independently. Further studies are needed to answer these questions.

Conflict of interest statement

H. Pickenbrock developed the LiN approach and is a member of LiN-Arge e.V., a not-for-profit organization that promotes the LiN approach.

V. U. Ludwig is related to H. Pickenbrock, the first author.

A. Zapf received a fee for the statistical analysis.

D. Dressler declares that no conflict of interest exists.

Manuscript received on 20 May 2014, revised version accepted on
22 October 2014.

Translated from the original German by Kersti Wagstaff, MA.

Corresponding author
Heidrun Pickenbrock M.Sc.
Klinik für Neurologie
Bereich Bewegungsstörungen
Medizinische Hochschule Hannover
Carl-Neuberg-Str. 1,
30625 Hannover , Germany

@For eReferences please refer to:
www.aerzteblatt-international.de/ref0315

eSupplement, eTables, eFigures:
www.aerzteblatt-international.de/15m0035

References

1. Heuschmann PU, Busse O, Wagner M, et al.: Frequency and care of stroke in Germany. Akt Neurol 2010; 37: 333–40.

2. Reddy M, Gill SS, Rochon PA: Preventing pressure ulcers: a systematic review. JAMA 2006; 296: 974–84.

3. Moore Z, Cowman S, Conroy RM: A randomised controlled clinical trial of repositioning, using the 30° tilt, for the prevention of pressure ulcers. J Clin Nurs 2011; 20: 2633–44.

4. Burk RS, Grap MJ: Backrest position in prevention of pressure ulcers and ventilator-associated pneumonia: conflicting recommendations. Heart Lung 2012; 41: 536–45.

5. Aries MJ, Elting JW, Stewart R, De Keyser J, Kremer B, Vroomen P: Cerebral blood flow velocity changes during upright positioning in bed after acute stroke: an observational study. BMJ Open 2013; 3: 1–8.

6. Barr J, Stocks J, Wagstaff S, Dey P: Positional interventions for acute stroke patients. The Cochrane Database of Systematic Reviews 2003; 4: CD004702.

7. Sullivan N, Schoelles KM: Preventing in-facility pressure ulcers as a patient safety strategy. A systematic review. Ann Intern Med 2013; 158: 410–6.

8. Stroke Units Trialists’ Collaboration: How do stroke units improve patient outcomes? A collaborative systematic review of the randomized trials. Stroke Unit Trialists’ Collaboration. Stroke 1997; 28: 2139–44.

9. Carr EK, Kenney FD: Positioning of the stroke patient: a review of the literature. Int J Nurs Stud 1992; 29: 355–69.

10. Hartnick A: Halt und Beweglichkeit für neurologische Patienten. Lagerung in Neutralstellung (LiN). Die Schwester Der Pfleger 2006; 45: 39–45.

11. Eberlein-Gonska M, Petzold T, Helaß G, Albrecht DM, Schmitt J: The incidence and determinants of decubitus ulcers in hospital care—an analysis of routine quality management data at a university hospital. Dtsch Arztebl Int 2013; 110: 550–6.

12. Pohl M, Rockstroh G, Rückriem S, et al.: Measurement of the effect of a bolus dose of intrathecal baclofen by continuous measurement of force under fibreglass casts. J Neurol 2002; 249: 1254–62.

13. Bohannon RW, Larkin PA, Smith MB, Horton MG: Shoulder pain in hemiplegia: statistical relationship with five variables. Arch Phys Med Rehabil 1986; 67: 514–6.

14. Ada L, Goddard E, McCully J, Stavrinos T, Bampton J: Thirty minutes of positioning reduces the development of shoulder external rotation contracture after stroke: a randomized controlled trial. Arch Phys Med Rehabil 2005; 86: 230–4.

15. German Clinical Trial Register: ID: DRKS00004163. https://drks–neu.uniklinik–freiburg.de (last accessed on 12 September 2013)

16. Friedman LM, Furberg CD, DeMets DL: Fundamentals of clinical trials, 3rd edition. New York: Springer 1998; 64–6.

17. van Swieten J, Koudstaal P, Visser M, Schouten H, van Gijn J: Interobserver agreement for the assessment of handicap in stroke patients. Stroke 1988; 19: 604–7.

18. Bobath B: Adult Hemiplegia: Evaluation and treatment. 3rd ed. Oxford: Heinemann Medical Books 1990; 76–7.

19. Davies PM: Steps to Follow: The comprehensive treatment of patients with hemiplegia. 2nd edition. Berlin: Springer 2000; 101–3.

20. Friedhoff M, Schieberle D: Praxis des Bobath-Konzeptes. Grundlagen – Handlings – Fallbeispiele. Stuttgart: Georg Thieme Verlag 2007; 93–101.

21. Klein–Tarolli E, Textor B: Bewegtes „Lagern“. Positions–Unterstützung nach Esther Klein–Tarolli. 4th edition. Dorsten: Verlag Ingrid Zimmermann 2008; 29–35.

22. Schulz KF, Altman DG, Moher D: CONSORT 2010 statement: Updated guidelines for reporting parallel group randomised trials. J Pharmacol Pharmacother 2010; 1, 1007.

23. Pope PM: Postural management and special seating. IN: Edwards S. Neurological physiotherapy. A problem solving approach. New York: Churchill Livingstone 1996; 159.

24. Dowswell G, Dowswell T, Young J: Adjusting stroke patients’ poor position: an observational study. J Adv Nurs 2000; 32: 286–91.

25. Jones A, Carr EK, Newham DJ, Wilson–Barnett J: Positioning of stroke patients: evaluation of a teaching intervention with nurses. Stroke 1998; 29: 1612–7.

26. Haarmann U: Das Bobath – Konzept in der Pflegepraxis. PflegeBull 2005; 1: 1–6.

27. Pua Y-H, Wrigley TW, Cowan SM, Bennel KL: Intrarater test-retest reliability of hip range of motion and hip muscle strength measurements in persons with hip osteoarthritis. Arch Phys Med Rehabil 2008; 89: 1146–53.

28. Muir SW, Correa CL, Beaupre L: Evaluating change in clinical status: reliability and measures of agreement for the assessment of glenohumeral range of motion. N Am J Sports Phys Ther 2010; 5: 98–110.

29. Borisova Y, Bohannon RW: Positioning to prevent or reduce shoulder range of motion impairments after stroke, a meta-analysis. Clin Rehabil 2009; 23: 681–6.

e1. Nussbaumer S, Leunig M, Glatthorn JF, Stauffacher S, Gerber H, Maffiuletti NA: Validity and test-retest reliability of manual goniometers for measuring passive hip range of motion in femoroacetabular impingement patients. BMC Musculoskeletal Disord 2010; 11: 194–205.

e2. Holm I, Bolstad B, Lütken T, Ervik A, Rokkum M, Stehen H: Reliability of goniometric measurements and visual estimates of hip ROM in patients with osteoarthrosis. Physiother Res Int 2000; 5: 241–8.

e3. Kolber MJ, Hanney WJ: The reliability and concurrent validity of shoulder mobility measurements using a digital inclinometer and goniometer: a technical report. Int J Sports Phys Ther 2012; 7: 306–13.

e4. De Jong LD, Nieuwboer A, Aufdemkampe G: The hemiplegic arm: interrater reliability and concurrent validity of passive range of motion measurements. Disabil Rehabil 2007; 29: 1442–8.

e5. Ada L, Goddard E, McCully J, Stavrinos T, Bampton J: Thirty minutes of positioning reduces the development of shoulder external rotation contracture after stroke, a randomized controlled trial. Arch Phys Med Rehabil 2005; 86: 230–4.

e6. De Jong LD, Nieuwboer A, Aufdemkampe G: Contracture preventive positioning of the hemiplegic arm in subacute stroke patients: a pilot randomized controlled trial. Clin Rehabil 2006; 20: 656–67.

e7. Gustafsson L, McKenna K: A programme of static positional stretches does not reduce hemiplegic shoulder pain or maintain shoulder range of motion—a randomized controlled trial. Clin Rehabil 2006; 20: 277–86.